WorldWideScience

Sample records for rendezvous guidance study

  1. Video-Guidance Design for the DART Rendezvous Mission

    Science.gov (United States)

    Ruth, Michael; Tracy, Chisholm

    2004-01-01

    NASA's Demonstration of Autonomous Rendezvous Technology (DART) mission will validate a number of different guidance technologies, including state-differenced GPS transfers and close-approach video guidance. The video guidance for DART will employ NASA/Marshall s Advanced Video Guidance Sensor (AVGS). This paper focuses on the terminal phase of the DART mission that includes close-approach maneuvers under AVGS guidance. The closed-loop video guidance design for DART is driven by a number of competing requirements, including a need for maximizing tracking bandwidths while coping with measurement noise and the need to minimize RCS firings. A range of different strategies for attitude control and docking guidance have been considered for the DART mission, and design decisions are driven by a goal of minimizing both the design complexity and the effects of video guidance lags. The DART design employs an indirect docking approach, in which the guidance position targets are defined using relative attitude information. Flight simulation results have proven the effectiveness of the video guidance design.

  2. Guidance and navigation for rendezvous with an uncooperative target

    Science.gov (United States)

    Telaar, J.; Schlaile, C.; Sommer, J.

    2018-06-01

    This paper presents a guidance strategy for a rendezvous with an uncooperative target. In the applied design reference mission, a spiral approach is commanded ensuring a collision-free relative orbit due to e/i-vector separation. The dimensions of the relative orbit are successively reduced by Δv commands which at the same time improve the observability of the relative state. The navigation is based on line-of-sight measurements. The relative state is estimated by an extended Kalman filter (EKF). The performance of this guidance and navigation strategy is demonstrated by extensive Monte Carlo simulations taking into account all major uncertainties like measurement errors, Δv execution errors, and differential drag.

  3. Spacecraft Rendezvous Guidance in Cluttered Dynamical Environments via Extreme Learning Machines, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — DeepAnalytX, Inc. proposes to investigate a new approach to perform real-time, closed-loop optimal and robust rendezvous guidance in space environments comprising a...

  4. A Study of Control Laws for Microsatellite Rendezvous with a Noncooperative Target

    National Research Council Canada - National Science Library

    Tschirhart, Troy

    2003-01-01

    This study investigated the feasibility of using a microsatellite to accomplish an orbital rendezvous with a noncooperative target, with a focus on the control laws necessary for achieving such a rendezvous...

  5. Spacecraft rendezvous and docking

    DEFF Research Database (Denmark)

    Jørgensen, John Leif

    1999-01-01

    The phenomenons and problems encountered when a rendezvous manoeuvre, and possible docking, of two spacecrafts has to be performed, have been the topic for numerous studies, and, details of a variety of scenarios has been analysed. So far, all solutions that has been brought into realization has...... been based entirely on direct human supervision and control. This paper describes a vision-based system and methodology, that autonomously generates accurate guidance information that may assist a human operator in performing the tasks associated with both the rendezvous and docking navigation...

  6. Guidance and Control of Position and Attitude for Rendezvous and Dock/Berthing with a Noncooperative/Target Spacecraft

    Directory of Open Access Journals (Sweden)

    Gilberto Arantes

    2014-01-01

    Full Text Available Noncooperative target spacecrafts are those assets in orbit that cannot convey any information about their states (position, attitude, and velocities or facilitate rendezvous and docking/berthing (RVD/B process. Designing a guidance, navigation, and control (GNC module for the chaser in a RVD/B mission with noncooperative target should be inevitably solved for on-orbit servicing technologies. The proximity operations and the guidance for achieving rendezvous problems are addressed in this paper. The out-of-plane maneuvers of proximity operations are explored with distinct subphases, including a chaser far approach in the target’s orbit to the first hold point and a closer approach to the final berthing location. Accordingly, guidance solutions are chosen for each subphase from the standard Hill based Closhessy-Willtshire (CW solution, elliptical fly-around, and Glideslope algorithms. The control is based on a linear quadratic regulator approach (LQR. At the final berthing location, attitude tracker based on a proportional derivative (PD form is tested to synchronize the chaser and target attitudes. The paper analyzes the performance of both controllers in terms of the tracking ability and the robustness. Finally, it prescribes any restrictions that may be imposed on the guidance during any subphase which can help to improve the controllers tracking ability.

  7. Space Shuttle Guidance, Navigation, and Rendezvous Knowledge Capture Reports. Revision 1

    Science.gov (United States)

    Goodman, John L.

    2011-01-01

    This document is a catalog and readers guide to lessons learned, experience, and technical history reports, as well as compilation volumes prepared by United Space Alliance personnel for the NASA/Johnson Space Center (JSC) Flight Dynamics Division.1 It is intended to make it easier for future generations of engineers to locate knowledge capture documentation from the Shuttle Program. The first chapter covers observations on documentation quality and research challenges encountered during the Space Shuttle and Orion programs. The second chapter covers the knowledge capture approach used to create many of the reports covered in this document. These chapters are intended to provide future flight programs with insight that could be used to formulate knowledge capture and management strategies. The following chapters contain descriptions of each knowledge capture report. The majority of the reports concern the Space Shuttle. Three are included that were written in support of the Orion Program. Most of the reports were written from the years 2001 to 2011. Lessons learned reports concern primarily the shuttle Global Positioning System (GPS) upgrade and the knowledge capture process. Experience reports on navigation and rendezvous provide examples of how challenges were overcome and how best practices were identified and applied. Some reports are of a more technical history nature covering navigation and rendezvous. They provide an overview of mission activities and the evolution of operations concepts and trajectory design. The lessons learned, experience, and history reports would be considered secondary sources by historians and archivists.

  8. Guidance and Navigation for Rendezvous and Proximity Operations with a Non-Cooperative Spacecraft at Geosynchronous Orbit

    Science.gov (United States)

    Barbee, Brent William; Carpenter, J. Russell; Heatwole, Scott; Markley, F. Landis; Moreau, Michael; Naasz, Bo J.; VanEepoel, John

    2010-01-01

    The feasibility and benefits of various spacecraft servicing concepts are currently being assessed, and all require that the servicer spacecraft perform rendezvous, proximity, and capture operations with the target spacecraft to be serviced. Many high-value spacecraft, which would be logical targets for servicing from an economic point of view, are located in geosynchronous orbit, a regime in which autonomous rendezvous and capture operations are not commonplace. Furthermore, existing GEO spacecraft were not designed to be serviced. Most do not have cooperative relative navigation sensors or docking features, and some servicing applications, such as de-orbiting of a non-functional spacecraft, entail rendezvous and capture with a spacecraft that may be non-functional or un-controlled. Several of these challenges have been explored via the design of a notional mission in which a nonfunctional satellite in geosynchronous orbit is captured by a servicer spacecraft and boosted into super-synchronous orbit for safe disposal. A strategy for autonomous rendezvous, proximity operations, and capture is developed, and the Orbit Determination Toolbox (ODTBX) is used to perform a relative navigation simulation to assess the feasibility of performing the rendezvous using a combination of angles-only and range measurements. Additionally, a method for designing efficient orbital rendezvous sequences for multiple target spacecraft is utilized to examine the capabilities of a servicer spacecraft to service multiple targets during the course of a single mission.

  9. Comparative study of rendezvous techniques in post-liver transplant biliary stricture.

    Science.gov (United States)

    Chang, Jae Hyuck; Lee, In Seok; Chun, Ho Jong; Choi, Jong Young; Yoon, Seung Kyoo; Kim, Dong Goo; You, Young Kyoung; Choi, Myung-Gyu; Han, Sok Won

    2012-11-07

    To investigate the usefulness of a new rendezvous technique for placing stents using the Kumpe (KMP) catheter in angulated or twisted biliary strictures. The rendezvous technique was performed in patients with a biliary stricture after living donor liver transplantation (LDLT) who required the exchange of percutaneous transhepatic biliary drainage catheters for inside stents. The rendezvous technique was performed using a guidewire in 19 patients (guidewire group) and using a KMP catheter in another 19 (KMP catheter group). We compared the two groups retrospectively. The baseline characteristics did not differ between the groups. The success rate for placing inside stents was 100% in both groups. A KMP catheter was easier to manipulate than a guidewire. The mean procedure time in the KMP catheter group (1012 s, range: 301-2006 s) was shorter than that in the guidewire group (2037 s, range: 251-6758 s, P = 0.022). The cumulative probabilities corresponding to the procedure time of the two groups were significantly different (P = 0.008). The factors related to procedure time were the rendezvous technique method, the number of inside stents, the operator, and balloon dilation of the stricture (P rendezvous technique method was the only significant factor related to procedure time (P = 0.010). The procedural complications observed included one case of mild acute pancreatitis and one case of acute cholangitis in the guidewire group, and two cases of mild acute pancreatitis in the KMP catheter group. The rendezvous technique involving use of the KMP catheter was a fast and safe method for placing inside stents in patients with LDLT biliary stricture that represents a viable alternative to the guidewire rendezvous technique.

  10. Rendezvous cannulation technique reduces post-ERCP pancreatitis: a prospective nationwide study of 12,718 ERCP procedures.

    Science.gov (United States)

    Swahn, Fredrik; Nilsson, Magnus; Arnelo, Urban; Löhr, Matthias; Persson, Gunnar; Enochsson, Lars

    2013-04-01

    The aim of this study was to investigate if intraoperative rendezvous cannulation reduces the risk of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) because there is no universal consensus on the optimal treatment of common bile duct stones. We performed a nationwide case-control study, nested within the cohort of ERCP procedures reported to the Swedish Registry for Gallstone Surgery and ERCP (GallRiks), between 2007 and 2009. Data were collected prospectively from a web-based registry of ERCP procedures that includes variables such as patient characteristics, indication, cannulation technique, diagnostic findings, therapeutic measures, and complications. The primary outcome was PEP. The registry included 12,718 ERCP procedures performed on patients without a history of previous ERCP. The risk of PEP when using the rendezvous technique compared with those who were cannulated by conventional means was reduced from 3.6 to 2.2% (odds ratio (OR) 0.5, 95% confidence interval 0.2-0.9, P=0.02). Although a significant reduction there are overall relatively few cases with PEP and the calculated numbers needed to treat to avoid one case of PEP is as high as 71. Other factors associated with increased risk of PEP were young age, prolonged procedure time, and elective ERCP. Rendezvous bile duct cannulation during ERCP reduces the risk of PEP from 3.6 to 2.2% compared with conventional biliary cannulation.

  11. A 10-year study of rendezvous intraoperative endoscopic retrograde cholangiography during cholecystectomy and the risk of post-ERCP pancreatitis.

    Science.gov (United States)

    Noel, Rozh; Enochsson, Lars; Swahn, Fredrik; Löhr, Matthias; Nilsson, Magnus; Permert, Johan; Arnelo, Urban

    2013-07-01

    Rendezvous intraoperative endoscopic retrograde cholangiography (RV-IOERC), also called guidewire-facilitated IOERC, is one of the single-stage options available for managing common bile duct stones (CBDS) during laparoscopic cholecystectomy. The objective of this study is to investigate procedure-related complications in IOERC patients and stone clearance. All patients who underwent IOERC between January 2000 and December 2009 were identified from the local registry of Karolinska University Hospital in Huddinge. Medical charts and ERC reports were studied, and descriptive statistics were obtained. Outcomes were procedure-related complications, especially post-ERCP pancreatitis (PEP), stone clearance, and mortality. 307 patients were identified. In 264 of the patients, the rendezvous cannulation technique was successful (86 %); in the remaining 43 patients, conventional cannulation technique was necessary. In total, PEP occurred in seven patients (2.28 %). One of the PEP patients was in the rendezvous cannulated group (0.37 %), whereas six patients developed PEP in the nonrendezvous group (13.95 %, p < 0.001). The primary stone clearance rate was 88.27 % (271/307). There was no mortality within 90 days in the series. IOERC with RV cannulation technique for management of CBDS during laparoscopic cholecystectomy has a low PEP rate and a high stone clearance rate, making it a safe and feasible method for removing CBDS. However, the technique requires logistics to perform IOERC in the operating theater. The present data suggest that IOERC with RV cannulation is superior to conventional cannulation with respect to risk of PEP.

  12. Optimal Rendezvous and Docking Simulator for Elliptical Orbits, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — It is proposed to develop and implement a simulation of spacecraft rendezvous and docking guidance, navigation, and control in elliptical orbit. The foundation of...

  13. Survey of orbital dynamics and control of space rendezvous

    Directory of Open Access Journals (Sweden)

    Luo Yazhong

    2014-02-01

    Full Text Available Rendezvous orbital dynamics and control (RODC is a key technology for operating space rendezvous and docking missions. This paper surveys the studies on RODC. Firstly, the basic relative dynamics equation set is introduced and its improved versions are evaluated. Secondly, studies on rendezvous trajectory optimization are commented from three aspects: the linear rendezvous, the nonlinear two-body rendezvous, and the perturbed and constrained rendezvous. Thirdly, studies on relative navigation are briefly reviewed, and then close-range control methods including automated control, manual control, and telecontrol are analyzed. Fourthly, advances in rendezvous trajectory safety and robust analysis are surveyed, and their applications in trajectory optimization are discussed. Finally, conclusions are drawn and prospects of studies on RODC are presented.

  14. Rendezvous maneuvers using Genetic Algorithm

    International Nuclear Information System (INIS)

    Dos Santos, Denílson Paulo Souza; De Almeida Prado, Antônio F Bertachini; Teodoro, Anderson Rodrigo Barretto

    2013-01-01

    The present paper has the goal of studying orbital maneuvers of Rendezvous, that is an orbital transfer where a spacecraft has to change its orbit to meet with another spacecraft that is travelling in another orbit. This transfer will be accomplished by using a multi-impulsive control. A genetic algorithm is used to find the transfers that have minimum fuel consumption

  15. Automatic rendezvous and docking systems functional and performance requirements

    Science.gov (United States)

    1985-01-01

    A generalized mission design scheme which utilizes a standard mission profile for all OMV rendezvous operations, recognizes typical operational constraints, and minimizes propellant penalties due to nodal regression effects was developed. This scheme has been used to demonstrate a unified guidance and navigation maneuver processor (the UMP), which supports all mission phases through station-keeping. The initial demonstration version of the Orbital Rendezvous Mission Planner (ORMP) was provided for evaluation purposes, and program operation was discussed.

  16. Optimal starting conditions for the rendezvous maneuver: Analytical and computational approach

    Science.gov (United States)

    Ciarcia, Marco

    The three-dimensional rendezvous between two spacecraft is considered: a target spacecraft on a circular orbit around the Earth and a chaser spacecraft initially on some elliptical orbit yet to be determined. The chaser spacecraft has variable mass, limited thrust, and its trajectory is governed by three controls, one determining the thrust magnitude and two determining the thrust direction. We seek the time history of the controls in such a way that the propellant mass required to execute the rendezvous maneuver is minimized. Two cases are considered: (i) time-to-rendezvous free and (ii) time-to-rendezvous given, respectively equivalent to (i) free angular travel and (ii) fixed angular travel for the target spacecraft. The above problem has been studied by several authors under the assumption that the initial separation coordinates and the initial separation velocities are given, hence known initial conditions for the chaser spacecraft. In this paper, it is assumed that both the initial separation coordinates and initial separation velocities are free except for the requirement that the initial chaser-to-target distance is given so as to prevent the occurrence of trivial solutions. Two approaches are employed: optimal control formulation (Part A) and mathematical programming formulation (Part B). In Part A, analyses are performed with the multiple-subarc sequential gradient-restoration algorithm for optimal control problems. They show that the fuel-optimal trajectory is zero-bang, namely it is characterized by two subarcs: a long coasting zero-thrust subarc followed by a short powered max-thrust braking subarc. While the thrust direction of the powered subarc is continuously variable for the optimal trajectory, its replacement with a constant (yet optimized) thrust direction produces a very efficient guidance trajectory. Indeed, for all values of the initial distance, the fuel required by the guidance trajectory is within less than one percent of the fuel required

  17. [Endoscopic ultrasound guided rendezvous for biliary drainage].

    Science.gov (United States)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem; Karstensen, John Gésdal

    2015-04-27

    Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from the stomach or duodenum to the common bile duct and from there on to the duodenum enabling ERCP. With a relatively high rate of success EUS-RV should be considered as an alternative to biliary drainage and surgical intervention.

  18. Demonstration of Autonomous Rendezvous Technology (DART) Project Summary

    Science.gov (United States)

    Rumford, TImothy E.

    2003-01-01

    Since the 1960's, NASA has performed numerous rendezvous and docking missions. The common element of all US rendezvous and docking is that the spacecraft has always been piloted by astronauts. Only the Russian Space Program has developed and demonstrated an autonomous capability. The Demonstration of Autonomous Rendezvous Technology (DART) project currently funded under NASA's Space Launch Initiative (SLI) Cycle I, provides a key step in establishing an autonomous rendezvous capability for the United States. DART's objective is to demonstrate, in space, the hardware and software necessary for autonomous rendezvous. Orbital Sciences Corporation intends to integrate an Advanced Video Guidance Sensor and Autonomous Rendezvous and Proximity Operations algorithms into a Pegasus upper stage in order to demonstrate the capability to autonomously rendezvous with a target currently in orbit. The DART mission will occur in April 2004. The launch site will be Vandenburg AFB and the launch vehicle will be a Pegasus XL equipped with a Hydrazine Auxiliary Propulsion System 4th stage. All mission objectives will be completed within a 24 hour period. The paper provides a summary of mission objectives, mission overview and a discussion on the design features of the chase and target vehicles.

  19. Trajectory control with continuous thrust applied to a rendezvous maneuver

    International Nuclear Information System (INIS)

    Santos, W G; Rocco, E M

    2013-01-01

    A rendezvous mission can be divided into the following phases: launch, phasing, far range rendezvous, close range rendezvous and mating (docking or berthing). This paper aims to present a close range rendezvous with closed loop controlled straight line trajectory. The approaching is executed on V-bar axis. A PID controller and continuous thrust are used to eliminate the residual errors in the trajectory. A comparative study about the linear and nonlinear dynamics is performed and the results showed that the linear equations become inaccurate insofar as the chaser moves away from the target

  20. 14 CFR 1214.111 - Rendezvous services.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Rendezvous services. 1214.111 Section 1214....111 Rendezvous services. (a) A rendezvous mission involves the rendezvous of the Space Shuttle orbiter... conditions for both dedicated and shared flight rendezvous services will be negotiated on a case-by-case...

  1. EUS-guided rendezvous for difficult biliary cannulation using a standardized algorithm: a multicenter prospective pilot study (with videos).

    Science.gov (United States)

    Iwashita, Takuji; Yasuda, Ichiro; Mukai, Tsuyoshi; Iwata, Keisuke; Ando, Nobuhiro; Doi, Shinpei; Nakashima, Masanori; Uemura, Shinya; Mabuchi, Masatoshi; Shimizu, Masahito

    2016-02-01

    Biliary cannulation is necessary in therapeutic ERCP for biliary disorders. EUS-guided rendezvous (EUS-RV) can salvage failed cannulation. Our aim was to determine the safety and efficacy of EUS-RV by using a standardized algorithm with regard to the endoscope position in a prospective study. EUS-RV was attempted after failed cannulation in 20 patients. In a standardized approach, extrahepatic bile duct (EHBD) cannulation was preferentially attempted from the second portion of the duodenum (D2) followed by additional approaches to the EHBD from the duodenal bulb (D1) or to the intrahepatic bile duct from the stomach, if necessary. A guidewire was placed in an antegrade fashion into the duodenum. After the guidewire was placed, the endoscope was exchanged for a duodenoscope to complete the cannulation. The bile duct was accessed from the D2 in 10 patients, but from the D1 in 5 patients and the stomach in 4 patients because of no dilation or tumor invasion at the distal EHBD. In the remaining patient, biliary puncture was not attempted due to the presence of collateral vessels. The guidewire was successfully manipulated in 80% of patients: 100% (10/10) with the D2 approach and 66.7% (6/9) with other approaches. The overall success rate was 80% (16/20). Failed EUS-RV was salvaged with a percutaneous approach in 2 patients, repeat ERCP in 1 patient, and conservative management in 1 patient. Minor adverse events occurred in 15% of patients (3/20). EUS-RV is a safe and effective salvage method. Using EUS-RV to approach the EHBD from the D2 may improve success rates. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  2. Autonomous Mars ascent and orbit rendezvous for earth return missions

    Science.gov (United States)

    Edwards, H. C.; Balmanno, W. F.; Cruz, Manuel I.; Ilgen, Marc R.

    1991-01-01

    The details of tha assessment of autonomous Mars ascent and orbit rendezvous for earth return missions are presented. Analyses addressing navigation system assessments, trajectory planning, targeting approaches, flight control guidance strategies, and performance sensitivities are included. Tradeoffs in the analysis and design process are discussed.

  3. 75 FR 44794 - Rendezvous International v.

    Science.gov (United States)

    2010-07-29

    ... FEDERAL MARITIME COMMISSION [Docket No. 10-07] Rendezvous International v. Chief Cargo Services, Inc., Kaiser Apparel, Inc., Edco Logistics, Inc., Oriental Logistics, Inc., and Razor Enterprise... Federal Maritime Commission (``Commission'') by Rendezvous International (``Rendezvous''), hereinafter...

  4. Multiple NEO Rendezvous Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

    2012-01-01

    The NASA Marshall Space Flight Center (MSFC) Advanced Concepts Office performed an assessment of the feasibility of using a near-term solar sail propulsion system to enable a single spacecraft to perform serial rendezvous operations at multiple Near Earth Objects (NEOs) within six years of launch on a small-to-moderate launch vehicle. The study baselined the use of the sail technology demonstrated in the mid-2000 s by the NASA In-Space Propulsion Technology Project and is scheduled to be demonstrated in space by 2014 as part of the NASA Technology Demonstration Mission Program. The study ground rules required that the solar sail be the only new technology on the flight; all other spacecraft systems and instruments must have had previous space test and qualification. The resulting mission concept uses an 80-m X 80-m 3-axis stabilized solar sail launched by an Athena-II rocket in 2017 to rendezvous with 1999 AO10, Apophis and 2001 QJ142. In each rendezvous, the spacecraft will perform proximity operations for approximately 30 days. The spacecraft science payload is simple and lightweight; it will consist of only the multispectral imager flown on the Near Earth Asteroid Rendezvous (NEAR) mission to 433 Eros and 253 Mathilde. Most non-sail spacecraft systems are based on the Messenger mission spacecraft. This paper will describe the objectives of the proposed mission, the solar sail technology to be employed, the spacecraft system and subsystems, as well as the overall mission profile.

  5. Automated low-thrust guidance for the orbital maneuvering vehicle

    Science.gov (United States)

    Rose, Richard E.; Schmeichel, Harry; Shortwell, Charles P.; Werner, Ronald A.

    1988-01-01

    This paper describes the highly autonomous OMV Guidance Navigation and Control system. Emphasis is placed on a key feature of the design, the low thrust guidance algorithm. The two guidance modes, orbit change guidance and rendezvous guidance, are discussed in detail. It is shown how OMV will automatically transfer from its initial orbit to an arbitrary target orbit and reach a specified rendezvous position relative to the target vehicle.

  6. Mars Sample Return - Launch and Detection Strategies for Orbital Rendezvous

    Science.gov (United States)

    Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

    2011-01-01

    This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/cache rover in 2018, an orbiter with an Earth return vehicle in 2022, and a fetch rover and ascent vehicle in 2024. Strategies are presented to launch the sample into a coplanar orbit with the Orbiter which facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits exist at 457 and 572 km which provide multiple launch opportunities with similar geometries for detection and rendezvous.

  7. Mars Sample Return: Launch and Detection Strategies for Orbital Rendezvous

    Science.gov (United States)

    Woolley, Ryan C.; Mattingly, Richard L.; Riedel, Joseph E.; Sturm, Erick J.

    2011-01-01

    This study sets forth conceptual mission design strategies for the ascent and rendezvous phase of the proposed NASA/ESA joint Mars Sample Return Campaign. The current notional mission architecture calls for the launch of an acquisition/ caching rover in 2018, an Earth return orbiter in 2022, and a fetch rover with ascent vehicle in 2024. Strategies are presented to launch the sample into a nearly coplanar orbit with the Orbiter which would facilitate robust optical detection, orbit determination, and rendezvous. Repeating ground track orbits existat 457 and 572 km which would provide multiple launch opportunities with similar geometries for detection and rendezvous.

  8. Optimal Non-Coplanar Launch to Quick Rendezvous

    National Research Council Canada - National Science Library

    Sears, Gregory

    1997-01-01

    The purpose of this study was to determine the feasibility of launching a Delta Clipper-like vehicle on an optimal, non-coplanar trajectory to rendezvous with an earth orbiting object in one orbit or less...

  9. Rendezvous and docking tracker

    Science.gov (United States)

    Ray, Art J.; Ross, Susan E.; Deming, Douglas R.

    1986-01-01

    A conceptual solid-state rendezvous and docking tracker (RDT) has been devised for generating range and attitude data for a docking vehicle relative to a target vehicle. Emphasis is placed on the approach of the Orbiter to a link with the Space Station. Three laser illuminators ring the optical axis of the lens a directed toward retroreflectors on the target vehicle. Each retroreflector is equipped with a bandpass filter for a designated illumination frequency. Data are collected sequentially over a 20 deg field of view as the range closes to 100-1000 m. A fourth ranging retroreflector 0.3 m from center is employed during close-in maneuvers. The system provides tracking data on motions with 6 deg of freedom, and furnishes 500 msec updates (to be enhanced to 100 msec) to the operator at a computer console.

  10. Endoscopic ultrasonography-guided rendezvous technique.

    Science.gov (United States)

    Tsuchiya, Takayoshi; Itoi, Takao; Sofuni, Atsushi; Tonozuka, Ryosuke; Mukai, Shuntaro

    2016-04-01

    Endoscopic retrograde cholangiopancreatography (ERCP) requires deep biliary cannulation. When deep biliary cannulation is failed, the endoscopic ultrasonography rendezvous technique (EUS-RV) is a useful salvage method. From the previous 15 articles that included 382 EUS-RV cases, the overall success rate of EUS-RV is 81 % with a complication rate of 10 %. In EUS-RV, the bile duct is punctured under EUS guidance and a guidewire is advanced into the duodenum via the papilla. The EUS scope is then switched to a duodenoscope and inserted into the bile duct over the guidewire exiting the papilla, or the guidewire is grasped with forceps and passed through the working channel; the catheter can then be inserted through the papilla over the wire. There are three puncture routes for EUS-RV: transgastric puncture of the intrahepatic bile duct (IHBD), transduodenal puncture of the extrahepatic bile duct (EHBD) via the proximal duodenum (D1), and transduodenal puncture of the EHBD via the second portion of the duodenum (D2). The puncture route for each patient should be selected based on the patient condition. GW selection for EUS-RV is critical, a hydrophilic GW is useful for this procedure. Although EUS-RV is now performed relatively routinely in a few high-volume centers, procedure standardization and the development of exclusive devices for EUS-RV are still underway. The development of exclusive devices for EUS-RV and prospective comparative studies with other salvage methods are needed to truly evaluate the procedure's usefulness and safety.

  11. Treatment for retained [corrected] common bile duct stones during laparoscopic cholecystectomy: the rendezvous technique.

    Science.gov (United States)

    Borzellino, Giuseppe; Rodella, Luca; Saladino, Edoardo; Catalano, Filippo; Politi, Leonardo; Minicozzi, Annamaria; Cordiano, Claudio

    2010-12-01

    To determine the feasibility and efficacy of the laparoscopic intraoperative rendezvous technique for common bile duct stones (CBDS). Case series. Verona University Hospital, Verona, Italy. A total of 110 patients were enrolled in the study; 47 had biliary colic; 39, acute cholecystitis; 19, acute biliary pancreatitis; and 5, acute biliary pancreatitis with associated acute cholecystitis. In all patients, CBDS diagnosis was reached by intraoperative cholangiography. Intraoperative endoscopy with rendezvous performed during laparascopic cholecystectomy for confirmed CBDS; for such a procedure, a transcystic guide wire was positioned into the duodenum. Intraoperative endoscopy with rendezvous was performed for retrieved CBDS during a laparoscopic cholecystectomy. Laparoscopic rendezvous feasibility, morbidity, postprocedure pancreatitis, and mortality. The laparoscopic rendezvous proved to be feasible in 95.5% (105 of 110 patients). The rendezvous failed in 3 cases of successfully performed laparoscopic cholecystectomy, and a conversion of the laparoscopy was needed in 2 cases of successful rendezvous. Two major complications and 2 cases of bleeding were registered after sphincterotomy was successfully performed with rendezvous, and severe acute pancreatitis complicated a traditional sphincterotomy performed after a failed rendezvous. Rendezvous is a feasible option for treatment of CBDS; it allows one to perform only 1 stage of treatment, even in acute cases such as cholecystitis and pancreatitis. Positioning of the guide wire may allow reduced complications secondary to papilla cannulation but not those of the endoscopic sphincterotomy.

  12. Smartphone Video Guidance Sensor for Small Satellites

    Data.gov (United States)

    National Aeronautics and Space Administration — Smartphone Video Guidance Sensor(SVGS) for Small Satellites will provide a low-cost,integrated rendezvous & proximity operations sensor system to allow an...

  13. Guidance for Identifying, Selecting and Evaluating Open Literature Studies

    Science.gov (United States)

    This guidance for Office of Pesticide Program staff will assist in their evaluation of open literature studies of pesticides. It also describes how we identify, select, and ensure that data we use in risk assessments is of sufficient scientific quality.

  14. Orbit Determination for a Microsatellite Rendezvous with a Non-Cooperative Target

    National Research Council Canada - National Science Library

    Foster, Brian

    2003-01-01

    This study investigated the minimum requirements to establish a satellite tracking system architecture for a hostile "parasitic microsatellite" to rendezvous with a larger, non-cooperative target satellite...

  15. History of Space Shuttle Rendezvous

    Science.gov (United States)

    Goodman, John L.

    2011-01-01

    This technical history is intended to provide a technical audience with an introduction to the rendezvous and proximity operations history of the Space Shuttle Program. It details the programmatic constraints and technical challenges encountered during shuttle development in the 1970s and over thirty years of shuttle missions. An overview of rendezvous and proximity operations on many shuttle missions is provided, as well as how some shuttle rendezvous and proximity operations systems and flight techniques evolved to meet new programmatic objectives. This revised edition provides additional information on Mercury, Gemini, Apollo, Skylab, and Apollo/Soyuz. Some chapters on the Space Shuttle have been updated and expanded. Four special focus chapters have been added to provide more detailed information on shuttle rendezvous. A chapter on the STS-39 mission of April/May 1991 describes the most complex deploy/retrieve mission flown by the shuttle. Another chapter focuses on the Hubble Space Telescope servicing missions. A third chapter gives the reader a detailed look at the February 2010 STS-130 mission to the International Space Station. The fourth chapter answers the question why rendezvous was not completely automated on the Gemini, Apollo, and Space Shuttle vehicles.

  16. EUS-guided biliary rendezvous using a short hydrophilic guidewire.

    Science.gov (United States)

    Dhir, Vinay; Kwek, Boon Eu Andrew; Bhandari, Suryaprakash; Bapat, Mukta; Maydeo, Amit

    2011-10-01

    BACKGROUND AND STUDY AIMS: EUS-guided rendezvous technique for biliary access requires expert manipulation of the guidewire across the downstream stricture or papilla. Published literature reports usage of the long-wire system to prevent loss of wire during scope exchange. We studied the efficacy of using a short hydrophilic guidewire in EUS-guided rendezvous. PATIENTS AND METHODS: This is a retrospective study conducted in a tertiary care referral centre. 15 patients underwent EUS-guided biliary rendezvous with short wire. EUS-guided transduodenal/transgastric puncture of the biliary system was performed, followed by anterograde placement of a hydrophilic short-wire (260 cm) across the downstream stricture and/or papilla. Retrograde access was then achieved by retrieving the trans-papillary wire, followed by standard ERCP intervention. Main outcome measurements were rates of procedural success and complications. RESULTS: EUS-guided biliary rendezvous was successful in 14 patients (93.3%). Failure was seen in one patient due to a tight malignant biliary stricture. One patient had peri-choledochal bile tracking which did not require any specific treatment. CONCLUSIONS: Short-wire system in EUS-guided biliary rendezvous is highly effective and safe. It is a useful salvage procedure for biliary cannulation in patients with accessible papilla.

  17. pedagogical guidance for south african consumer studies education

    African Journals Online (AJOL)

    user

    preferred teaching-learning strategies utilised internationally in subjects related to Consumer. ISSN 0378-5254 Journal of Family Ecology and Consumer Sciences, Vol 42, 2014. 48. Pedagogical guidance for South African Consumer Studies education. 1 The seven theory content topics contained in the Consumer Studies ...

  18. Integrated vision-based GNC for autonomous rendezvous and capture around Mars

    Science.gov (United States)

    Strippoli, L.; Novelli, G.; Gil Fernandez, J.; Colmenarejo, P.; Le Peuvedic, C.; Lanza, P.; Ankersen, F.

    2015-06-01

    Integrated GNC (iGNC) is an activity aimed at designing, developing and validating the GNC for autonomously performing the rendezvous and capture phase of the Mars sample return mission as defined during the Mars sample return Orbiter (MSRO) ESA study. The validation cycle includes testing in an end-to-end simulator, in a real-time avionics-representative test bench and, finally, in a dynamic HW in the loop test bench for assessing the feasibility, performances and figure of merits of the baseline approach defined during the MSRO study, for both nominal and contingency scenarios. The on-board software (OBSW) is tailored to work with the sensors, actuators and orbits baseline proposed in MSRO. The whole rendezvous is based on optical navigation, aided by RF-Doppler during the search and first orbit determination of the orbiting sample. The simulated rendezvous phase includes also the non-linear orbit synchronization, based on a dedicated non-linear guidance algorithm robust to Mars ascent vehicle (MAV) injection accuracy or MAV failures resulting in elliptic target orbits. The search phase is very demanding for the image processing (IP) due to the very high visual magnitude of the target wrt. the stellar background, and the attitude GNC requires very high pointing stability accuracies to fulfil IP constraints. A trade-off of innovative, autonomous navigation filters indicates the unscented Kalman filter (UKF) as the approach that provides the best results in terms of robustness, response to non-linearities and performances compatibly with computational load. At short range, an optimized IP based on a convex hull algorithm has been developed in order to guarantee LoS and range measurements from hundreds of metres to capture.

  19. Model predictive control for spacecraft rendezvous in elliptical orbit

    Science.gov (United States)

    Li, Peng; Zhu, Zheng H.

    2018-05-01

    This paper studies the control of spacecraft rendezvous with attitude stable or spinning targets in an elliptical orbit. The linearized Tschauner-Hempel equation is used to describe the motion of spacecraft and the problem is formulated by model predictive control. The control objective is to maximize control accuracy and smoothness simultaneously to avoid unexpected change or overshoot of trajectory for safe rendezvous. It is achieved by minimizing the weighted summations of control errors and increments. The effects of two sets of horizons (control and predictive horizons) in the model predictive control are examined in terms of fuel consumption, rendezvous time and computational effort. The numerical results show the proposed control strategy is effective.

  20. Autonomous spacecraft rendezvous and docking

    Science.gov (United States)

    Tietz, J. C.; Almand, B. J.

    A storyboard display is presented which summarizes work done recently in design and simulation of autonomous video rendezvous and docking systems for spacecraft. This display includes: photographs of the simulation hardware, plots of chase vehicle trajectories from simulations, pictures of the docking aid including image processing interpretations, and drawings of the control system strategy. Viewgraph-style sheets on the display bulletin board summarize the simulation objectives, benefits, special considerations, approach, and results.

  1. Endoskopisk ultralydvejledt rendezvous til intern drænage ved galdevejsobstruktion

    DEFF Research Database (Denmark)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem

    2015-01-01

    Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from...

  2. Rendezvous terminal phase automatic braking sequencing and targeting. [for space shuttle orbiter

    Science.gov (United States)

    Kachmar, P. M.

    1973-01-01

    The purpose of the rendezvous terminal phase braking program is to provide the means of automatically bringing the primary orbiter within desired station keeping boundaries relative to the target satellite. A detailed discussion is presented on the braking program and its navigation, targeting, and guidance functions.

  3. Endoscopic retrograde cholangiopancreatography with rendezvous cannulation reduces pancreatic injury.

    Science.gov (United States)

    Swahn, Fredrik; Regnér, Sara; Enochsson, Lars; Lundell, Lars; Permert, Johan; Nilsson, Magnus; Thorlacius, Henrik; Arnelo, Urban

    2013-09-28

    To examine whether rendezvous endoscopic retrograde cholangiopancreatography (ERCP) is associated with less pancreatic damage, measured as leakage of proenzymes, than conventional ERCP. Patients (n = 122) with symptomatic gallstone disease, intact papilla and no ongoing inflammation, were prospectively enrolled in this case-control designed study. Eighty-one patients were subjected to laparoscopic cholecystectomy and if intraoperative cholangiography suggested common bile duct stones (CBDS), rendezvous ERCP was performed intraoperatively (n = 40). Patients with a negative cholangiogram constituted the control group (n = 41). Another 41 patients with CBDS, not subjected to surgery, underwent conventional ERCP. Pancreatic proenzymes, procarboxypeptidase B and trypsinogen-2 levels in plasma, were analysed at 0, 4, 8 and 24 h. The proenzymes were determined in-house with a double-antibody enzyme linked immunosorbent assay. Pancreatic amylase was measured by an enzymatic colourimetric modular analyser with the manufacturer's reagents. All samples were blinded at analysis. Post ERCP pancreatitis (PEP) occurred in 3/41 (7%) of the patients cannulated with conventional ERCP and none in the rendezvous group. Increased serum levels indicating pancreatic leakage were significantly higher in the conventional ERCP group compared with the rendezvous ERCP group regarding pancreatic amylase levels in the 4- and 8-h samples (P = 0.0015; P = 0.03), procarboxypeptidase B in the 4- and 8-h samples (P rendezvous cannulation technique compared with patients that underwent cholecystectomy alone (control group). Post procedural concentrations of pancreatic amylase and procarboxypeptidase B were significantly correlated with pancreatic duct cannulation and opacification. Rendezvous ERCP reduces pancreatic enzyme leakage compared with conventional ERCP cannulation technique. Thus, laparo-endoscopic technique can be recommended with the ambition to minimise the risk for post ERCP

  4. Inverse simulation system for evaluating handling qualities during rendezvous and docking

    Science.gov (United States)

    Zhou, Wanmeng; Wang, Hua; Thomson, Douglas; Tang, Guojin; Zhang, Fan

    2017-08-01

    The traditional method used for handling qualities assessment of manned space vehicles is too time-consuming to meet the requirements of an increasingly fast design process. In this study, a rendezvous and docking inverse simulation system to assess the handling qualities of spacecraft is proposed using a previously developed model-predictive-control architecture. By considering the fixed discrete force of the thrusters of the system, the inverse model is constructed using the least squares estimation method with a hyper-ellipsoidal restriction, the continuous control outputs of which are subsequently dispersed by pulse width modulation with sensitivity factors introduced. The inputs in every step are deemed constant parameters, and the method could be considered as a general method for solving nominal, redundant, and insufficient inverse problems. The rendezvous and docking inverse simulation is applied to a nine-degrees-of-freedom platform, and a novel handling qualities evaluation scheme is established according to the operation precision and astronauts' workload. Finally, different nominal trajectories are scored by the inverse simulation and an established evaluation scheme. The scores can offer theoretical guidance for astronaut training and more complex operation missions.

  5. STS-134 Re-Rendezvous Design History

    Science.gov (United States)

    Stuit, Timothy D.

    2011-01-01

    In preparation to provide the capability for the Orion spacecraft to rendezvous with the International Space Station (ISS), a new suite of relative navigation sensors are in development and will be tested on one of the final Space Shuttle missions to ISS. The National Aeronautics and Space Administration (NASA) commissioned a flight test of prototypes of the instruments on STS-134, in order to test their performance in the space environment during the nominal rendezvous and docking, as well as a re-rendezvous dedicated to testing the prototype sensors following the undocking of the Space Shuttle Orbiter at the end of the mission. Unlike the initial rendezvous and docking, the re-rendezvous profile would replicate the newly designed Orion coelliptic approach trajectory, something never before attempted with the Shuttle Orbiter. Therefore, there were a number of new parameters that needed to be conceived of, designed, and tested for this re-rendezvous to make the flight test successful. And all of this work had to be integrated with the normal operations of the ISS and Shuttle and had to conform to the constraints of the mission and vehicles. The result of this work is a separation and re-rendezvous trajectory design that will prove not only the design of the relative navigation sensors for the Orion vehicle, but also will serve as a proof of concept for the Orion rendezvous trajectory itself. This document presents the analysis and decision making process involved in attaining the final STS-134 re-rendezvous design.

  6. The comet rendezvous asteroid flyby mission

    International Nuclear Information System (INIS)

    Morrison, D.; Neugebauer, M.; Weissman, P.R.

    1989-01-01

    The Comet Rendezvous Asteroid Flyby (CRAF) mission is designed to answer the many questions raised by the Halley missions by exploring a cometary nucleus in detail, following it around its orbit and studying its changing activity as it moves closer to and then away from the Sun. In addition, on its way to rendezvous with the comet, CRAF will fly by a large, primitive class main belt asteroid and will return valuable data for comparison with the comet results. The selected asteroid is 449 Hamburga with a diameter of 88 km and a surface composition of carbonaceous chondrite meteorites. The expected flyby date is January, 1998. The CRAF spacecraft will continue to make measurements in orbit around the cometary nucleus as they both move closer to the Sun, until the dust and gas hazard becomes unsafe. At that point the spacecraft will move in and out between 50 and 2,500 kilometers to study the inner coma and the cometary ionosphere, and to collect dust and gas samples for onboard analysis. Following perihelion, the spacecraft will make a 50,000 km excursion down the comet's tail, further investigating the solar wind interaction with the cometary atmosphere. The spacecraft will return to the vicinity of the nucleus about four months after perihelion to observe the changes that have taken place. If the spacecraft remains healthy and adequate fuel is still onboard, an extended mission to follow the comet nucleus out to aphelion is anticipated

  7. Design and Implementation of the Automated Rendezvous Targeting Algorithms for Orion

    Science.gov (United States)

    DSouza, Christopher; Weeks, Michael

    2010-01-01

    The Orion vehicle will be designed to perform several rendezvous missions: rendezvous with the ISS in Low Earth Orbit (LEO), rendezvous with the EDS/Altair in LEO, a contingency rendezvous with the ascent stage of the Altair in Low Lunar Orbit (LLO) and a contingency rendezvous in LLO with the ascent and descent stage in the case of an aborted lunar landing. Therefore, it is not difficult to realize that each of these scenarios imposes different operational, timing, and performance constraints on the GNC system. To this end, a suite of on-board guidance and targeting algorithms have been designed to meet the requirement to perform the rendezvous independent of communications with the ground. This capability is particularly relevant for the lunar missions, some of which may occur on the far side of the moon. This paper will describe these algorithms which are designed to be structured and arranged in such a way so as to be flexible and able to safely perform a wide variety of rendezvous trajectories. The goal of the algorithms is not to merely fly one specific type of canned rendezvous profile. Conversely, it was designed from the start to be general enough such that any type of trajectory profile can be flown.(i.e. a coelliptic profile, a stable orbit rendezvous profile, and a expedited LLO rendezvous profile, etc) all using the same rendezvous suite of algorithms. Each of these profiles makes use of maneuver types which have been designed with dual goals of robustness and performance. They are designed to converge quickly under dispersed conditions and they are designed to perform many of the functions performed on the ground today. The targeting algorithms consist of a phasing maneuver (NC), an altitude adjust maneuver (NH), and plane change maneuver (NPC), a coelliptic maneuver (NSR), a Lambert targeted maneuver, and several multiple-burn targeted maneuvers which combine one of more of these algorithms. The derivation and implementation of each of these

  8. Concurrent image-based visual servoing with adaptive zooming for non-cooperative rendezvous maneuvers

    Science.gov (United States)

    Pomares, Jorge; Felicetti, Leonard; Pérez, Javier; Emami, M. Reza

    2018-02-01

    An image-based servo controller for the guidance of a spacecraft during non-cooperative rendezvous is presented in this paper. The controller directly utilizes the visual features from image frames of a target spacecraft for computing both attitude and orbital maneuvers concurrently. The utilization of adaptive optics, such as zooming cameras, is also addressed through developing an invariant-image servo controller. The controller allows for performing rendezvous maneuvers independently from the adjustments of the camera focal length, improving the performance and versatility of maneuvers. The stability of the proposed control scheme is proven analytically in the invariant space, and its viability is explored through numerical simulations.

  9. Fusion Guidance in Endovascular Peripheral Artery Interventions: A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Sailer, Anna M., E-mail: anni.sailer@mumc.nl; Haan, Michiel W. de, E-mail: m.de.haan@mumc.nl; Graaf, Rick de, E-mail: r.de.graaf@mumc.nl; Zwam, Willem H. van, E-mail: w.van.zwam@mumc.nl [Maastricht University Medical Center, Department of Radiology (Netherlands); Schurink, Geert Willem H., E-mail: gwh.schurink@mumc.nl [Maastricht University Medical Center, Department of Surgery (Netherlands); Nelemans, Patricia J., E-mail: patty.nelemans@maastrichtuniversity.nl [Maastricht University Medical Centre, Department of Epidemiology (Netherlands); Wildberger, Joachim E., E-mail: j.wildberger@mumc.nl; Das, Marco, E-mail: m.das@mumc.nl [Maastricht University Medical Center, Department of Radiology (Netherlands)

    2015-04-15

    PurposeThis study was designed to evaluate the feasibility of endovascular guidance by means of live fluoroscopy fusion with magnetic resonance angiography (MRA) and computed tomography angiography (CTA).MethodsFusion guidance was evaluated in 20 endovascular peripheral artery interventions in 17 patients. Fifteen patients had received preinterventional diagnostic MRA and two patients had undergone CTA. Time for fluoroscopy with MRA/CTA coregistration was recorded. Feasibility of fusion guidance was evaluated according to the following criteria: for every procedure the executing interventional radiologists recorded whether 3D road-mapping provided added value (yes vs. no) and whether PTA and/or stenting could be performed relying on the fusion road-map without need for diagnostic contrast-enhanced angiogram series (CEAS) (yes vs. no). Precision of the fusion road-map was evaluated by recording maximum differences between the position of the vasculature on the virtual CTA/MRA images and conventional angiography.ResultsAverage time needed for image coregistration was 5 ± 2 min. Three-dimensional road-map added value was experienced in 15 procedures in 12 patients. In half of the patients (8/17), intervention was performed relying on the fusion road-map only, without diagnostic CEAS. In two patients, MRA roadmap showed a false-positive lesion. Excluding three patients with inordinate movements, mean difference in position of vasculature on angiography and MRA/CTA road-map was 1.86 ± 0.95 mm, implying that approximately 95 % of differences were between 0 and 3.72 mm (2 ± 1.96 standard deviation).ConclusionsFluoroscopy with MRA/CTA fusion guidance for peripheral artery interventions is feasible. By reducing the number of CEAS, this technology may contribute to enhance procedural safety.

  10. Fusion Guidance in Endovascular Peripheral Artery Interventions: A Feasibility Study

    International Nuclear Information System (INIS)

    Sailer, Anna M.; Haan, Michiel W. de; Graaf, Rick de; Zwam, Willem H. van; Schurink, Geert Willem H.; Nelemans, Patricia J.; Wildberger, Joachim E.; Das, Marco

    2015-01-01

    PurposeThis study was designed to evaluate the feasibility of endovascular guidance by means of live fluoroscopy fusion with magnetic resonance angiography (MRA) and computed tomography angiography (CTA).MethodsFusion guidance was evaluated in 20 endovascular peripheral artery interventions in 17 patients. Fifteen patients had received preinterventional diagnostic MRA and two patients had undergone CTA. Time for fluoroscopy with MRA/CTA coregistration was recorded. Feasibility of fusion guidance was evaluated according to the following criteria: for every procedure the executing interventional radiologists recorded whether 3D road-mapping provided added value (yes vs. no) and whether PTA and/or stenting could be performed relying on the fusion road-map without need for diagnostic contrast-enhanced angiogram series (CEAS) (yes vs. no). Precision of the fusion road-map was evaluated by recording maximum differences between the position of the vasculature on the virtual CTA/MRA images and conventional angiography.ResultsAverage time needed for image coregistration was 5 ± 2 min. Three-dimensional road-map added value was experienced in 15 procedures in 12 patients. In half of the patients (8/17), intervention was performed relying on the fusion road-map only, without diagnostic CEAS. In two patients, MRA roadmap showed a false-positive lesion. Excluding three patients with inordinate movements, mean difference in position of vasculature on angiography and MRA/CTA road-map was 1.86 ± 0.95 mm, implying that approximately 95 % of differences were between 0 and 3.72 mm (2 ± 1.96 standard deviation).ConclusionsFluoroscopy with MRA/CTA fusion guidance for peripheral artery interventions is feasible. By reducing the number of CEAS, this technology may contribute to enhance procedural safety

  11. Fusion guidance in endovascular peripheral artery interventions: a feasibility study.

    Science.gov (United States)

    Sailer, Anna M; de Haan, Michiel W; de Graaf, Rick; van Zwam, Willem H; Schurink, Geert Willem H; Nelemans, Patricia J; Wildberger, Joachim E; Das, Marco

    2015-04-01

    This study was designed to evaluate the feasibility of endovascular guidance by means of live fluoroscopy fusion with magnetic resonance angiography (MRA) and computed tomography angiography (CTA). Fusion guidance was evaluated in 20 endovascular peripheral artery interventions in 17 patients. Fifteen patients had received preinterventional diagnostic MRA and two patients had undergone CTA. Time for fluoroscopy with MRA/CTA coregistration was recorded. Feasibility of fusion guidance was evaluated according to the following criteria: for every procedure the executing interventional radiologists recorded whether 3D road-mapping provided added value (yes vs. no) and whether PTA and/or stenting could be performed relying on the fusion road-map without need for diagnostic contrast-enhanced angiogram series (CEAS) (yes vs. no). Precision of the fusion road-map was evaluated by recording maximum differences between the position of the vasculature on the virtual CTA/MRA images and conventional angiography. Average time needed for image coregistration was 5 ± 2 min. Three-dimensional road-map added value was experienced in 15 procedures in 12 patients. In half of the patients (8/17), intervention was performed relying on the fusion road-map only, without diagnostic CEAS. In two patients, MRA roadmap showed a false-positive lesion. Excluding three patients with inordinate movements, mean difference in position of vasculature on angiography and MRA/CTA road-map was 1.86 ± 0.95 mm, implying that approximately 95 % of differences were between 0 and 3.72 mm (2 ± 1.96 standard deviation). Fluoroscopy with MRA/CTA fusion guidance for peripheral artery interventions is feasible. By reducing the number of CEAS, this technology may contribute to enhance procedural safety.

  12. Comprehensive asynchronous symmetric rendezvous algorithm in ...

    Indian Academy of Sciences (India)

    Meenu Chawla

    2017-11-10

    Nov 10, 2017 ... Simulation results affirm that CASR algorithm performs better in terms of average time-to-rendezvous as compared ... process; neighbour discovery; symmetric rendezvous algorithm. 1. .... dezvous in finite time under the symmetric model. The CH ..... CASR algorithm in Matlab 7.11 and performed several.

  13. Early laparoendoscopic rendezvous for acute biliary pancreatitis: preliminary results.

    Science.gov (United States)

    Borzellino, G; Lombardo, F; Minicozzi, A M; Donataccio, M; Cordiano, C

    2010-02-01

    Early restored patency of the papilla has been hypothesized to reduce complications and mortality of acute biliary pancreatitis. The aim of this study was to evaluate the role of urgent laparoscopic cholecystectomy with intraoperative cholangiography and rendezvous when necessary in acute biliary pancreatitis natural history. Patients observed in the early stage of an acute biliary pancreatitis were included in the study. Operative risk assessment based on American Society of Anesthesiologists (ASA) score allowed the performance of urgent laparoscopic cholecystectomy within 72 h from onset of symptoms in 55 patients and a delayed intervention during the same admission in 21 patients. Intraoperative cholangiography was performed in all cases, and clearance of common bile duct was performed by flushing when possible, or rendezvous when necessary. Evolution of pancreatitis was evaluated with clinical and radiological monitoring. Urgent laparoscopic cholecystectomy was performed in all cases without conversion. At intraoperative cholangiography common bile duct was free in 25 patients, a papillary spasm was observed in 9, and common bile duct stones in 21 patients. Patency of the papilla was restored by flushing in 13 patients, while a rendezvous was necessary in 17 patients. The rate of organ failure and pancreatic necrosis was 1.8%, overall mortality was 1.8%, and overall morbidity 21.8%. No infectious complications of peripancreatic collections were observed. Urgent laparoscopic cholecystectomy with selective intraoperative rendezvous may be considered as a treatment option in the early stage of acute biliary pancreatitis.

  14. Studying Wind Energy/Bird Interactions: A Guidance Document

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R. [California Energy Commission (US); Morrison, M. [California State Univ., Sacramento, CA (US); Sinclair, K. [Dept. of Energy/National Renewable Energy Lab. (US); Strickland, D. [WEST, Inc. (US)

    1999-12-01

    This guidance document is a product of the Avian Subcommittee of the National Wind Coordinating Committee (NWCC). The NWCC was formed to better understand and promote responsible, credible, and comparable avian/wind energy interaction studies. Bird mortality is a concern and wind power is a potential clean and green source of electricity, making study of wind energy/bird interactions essential. This document provides an overview for regulators and stakeholders concerned with wind energy/bird interactions, as well as a more technical discussion of the basic concepts and tools for studying such interactions.

  15. An autonomous rendezvous and docking system using cruise missile technologies

    Science.gov (United States)

    Jones, Ruel Edwin

    1991-01-01

    In November 1990 the Autonomous Rendezvous & Docking (AR&D) system was first demonstrated for members of NASA's Strategic Avionics Technology Working Group. This simulation utilized prototype hardware from the Cruise Missile and Advanced Centaur Avionics systems. The object was to show that all the accuracy, reliability and operational requirements established for a space craft to dock with Space Station Freedom could be met by the proposed system. The rapid prototyping capabilities of the Advanced Avionics Systems Development Laboratory were used to evaluate the proposed system in a real time, hardware in the loop simulation of the rendezvous and docking reference mission. The simulation permits manual, supervised automatic and fully autonomous operations to be evaluated. It is also being upgraded to be able to test an Autonomous Approach and Landing (AA&L) system. The AA&L and AR&D systems are very similar. Both use inertial guidance and control systems supplemented by GPS. Both use an Image Processing System (IPS), for target recognition and tracking. The IPS includes a general purpose multiprocessor computer and a selected suite of sensors that will provide the required relative position and orientation data. Graphic displays can also be generated by the computer, providing the astronaut / operator with real-time guidance and navigation data with enhanced video or sensor imagery.

  16. 76 FR 82306 - Draft Guidance for Industry on Use of Histology in Biomarker Qualification Studies; Availability

    Science.gov (United States)

    2011-12-30

    ...] Draft Guidance for Industry on Use of Histology in Biomarker Qualification Studies; Availability AGENCY... announcing the availability of a draft guidance for industry entitled ``Use of Histology in Biomarker... studies for which histology is a reference standard. This guidance discusses the processes that should be...

  17. Randomised study on single stage laparo-endoscopic rendezvous (intra-operative ERCP) procedure versus two stage approach (Pre-operative ERCP followed by laparoscopic cholecystectomy) for the management of cholelithiasis with choledocholithiasis.

    Science.gov (United States)

    Sahoo, Manash Ranjan; Kumar, Anil T; Patnaik, Aashish

    2014-07-01

    The 'Rendezvous' technique consists of laparoscopic cholecystectomy (LC) standards with intra-operative cholangiography followed by endoscopic sphincterotomy. The sphincterotome is driven across the papilla through a guidewire inserted by the transcystic route. In this study, we intended to compare the two methods in a prospective randomised trial. From 2005 to 2012, we enrolled 83 patients with a diagnosis of cholecysto-choledocolithiasis. They were randomised into two groups. In 'group-A',41 patients were treated with two stages management, first by pre-operative endoscopic retrograde cholangiopancreatography (ERCP) and common bile duct (CBD) clearance and second by LC. In 'group-B', 42 patients were treated with LC and intra-operative cholangiography; and when diagnosis of choledocholithiasis was confirmed, patients had undergone one stage management of by Laparo-endoscopic Rendezvous technique. In arm-A and arm-B groups, complete CBD clearance was achieved in 29 and 38 patients, respectively. Failure of the treatment in arm-A was 29% and in arm-B was 9.5%. In arm-A, selective CBD cannulation was achieved in 33 cases (80.5%) and in arm-B in 39 cases (93%). In arm-Agroup, post-ERCP hyperamylasia was presented in nine patients (22%) and severe pancreatitis in five patients (12%) versus none of the patients (0%) in arm-B group, respectively. Mean post-operative hospital stay in arm-A and arm-B groups are 10.9 and 6.8 days, respectively. One stage laparo-endoscopic rendezvous approach increases selective cannulation of CBD, reduces post-ERCP pancreatitis, reduces days of hospital stay, increases patient's compliance and prevents unnecessary intervention to CBD.

  18. Percutaneous-endoscopic rendezvous procedure for the management of bile duct injuries after cholecystectomy: short- and long-term outcomes

    NARCIS (Netherlands)

    Schreuder, Anne Marthe; Booij, Klaske A. C.; de Reuver, Philip R.; van Delden, Otto M.; van Lienden, Krijn P.; Besselink, Marc G.; Busch, Olivier R.; Gouma, Dirk J.; Rauws, Erik A. J.; van Gulik, Thomas M.

    2018-01-01

    Bile duct injury (BDI) remains a daunting complication of laparoscopic cholecystectomy. In patients with complex BDI, a percutaneous-endoscopic rendezvous procedure may be required to establish bile duct continuity. The aim of this study was to assess short- and long-term outcomes of the rendezvous

  19. A Summary of the Rendezvous, Proximity Operations, Docking, and Undocking (RPODU) Lessons Learned from the Defense Advanced Research Project Agency (DARPA) Orbital Express (OE) Demonstration System Mission

    Science.gov (United States)

    Dennehy, Cornelius J.; Carpenter, James R.

    2011-01-01

    The Guidance, Navigation, and Control (GN&C) Technical Discipline Team (TDT) sponsored Dr. J. Russell Carpenter, a Navigation and Rendezvous Subject Matter Expert (SME) from NASA's Goddard Space Flight Center (GSFC), to provide support to the Defense Advanced Research Project Agency (DARPA) Orbital Express (OE) rendezvous and docking flight test that was conducted in 2007. When that DARPA OE mission was completed, Mr. Neil Dennehy, NASA Technical Fellow for GN&C, requested Dr. Carpenter document his findings (lessons learned) and recommendations for future rendezvous missions resulting from his OE support experience. This report captures lessons specifically from anomalies that occurred during one of OE's unmated operations.

  20. The Modular Clock Algorithm for Blind Rendezvous

    Science.gov (United States)

    2009-03-26

    and Computer Engineering Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training...capabilities in spectrum management and particularly in harvesting unused portions of pre-allocated band- width under DSA. The term “cognitive radio” was...of rendezvous and our role as the waiter . However, if the “child” refuses to move from non-common spectrum, rendezvous cannot occur. Bluetooth

  1. Rendezvous and Docking for Space Exploration

    Science.gov (United States)

    Machula, M. F.; Crain, T.; Sandhoo, G. S.

    2005-01-01

    To achieve the exploration goals, new approaches to exploration are being envisioned that include robotic networks, modular systems, pre-positioned propellants and in-space assembly in Earth orbit, Lunar orbit and other locations around the cosmos. A fundamental requirement for rendezvous and docking to accomplish in-space assembly exists in each of these locations. While existing systems and technologies can accomplish rendezvous and docking in low earth orbit, and rendezvous and docking with crewed systems has been successfully accomplished in low lunar orbit, our capability must extend toward autonomous rendezvous and docking. To meet the needs of the exploration vision in-space assembly requiring both crewed and uncrewed vehicles will be an integral part of the exploration architecture. This paper focuses on the intelligent application of autonomous rendezvous and docking technologies to meet the needs of that architecture. It also describes key technology investments that will increase the exploration program's ability to ensure mission success, regardless of whether the rendezvous are fully automated or have humans in the loop.

  2. Repeated rendezvous treatment of PTBD and ERCP in patients with recurrent obstructive jaundice.

    Science.gov (United States)

    Liu, Yingdi; Meng, Jianyun; Wang, Jianhua; Wang, Zhiqiang; Wang, Xiangdong; Linghu, Enqiang; Li, Wen; Yang, Yunsheng

    2010-01-01

    Repeated applications of rendezvous technique combining percutaneous transhepatic biliary drainage (PTBD) with endoscopic retrograde cholangiopancreatography (ERCP) (PE) in patients with recurrent obstructive jaundice have not been reported. The present study aimed to evaluate treatment effects of this technique in patients who previously received the same rendezvous treatment. Repeated PE rendezvous procedure was performed in 27 patients who received the same procedure previously and had recurrent obstructive jaundice. Twenty-two patients were treated by second-time rendezvous procedure and five patients by third-time. The clinical characteristics and therapeutic effects were retrospectively analyzed. By means of repeated rendezvous technique, 26 patients gained access to the bile duct and were successfully implanted new stents, only one failed with stent implantation. Total serum bilirubin level decreased within one week from 221.89 +/- 64.70 micromol/L to 156.0 +/- 32.2 micromol/L in patients with second-time treatment and from 297.07 +/- 109.12 micromol/L to 238.77 +/- 36.81 micromol/L in patients with third-time treatment. There was no severe complications observed that are associated with repeated PE procedure. Rendezvous procedure of PTBD and ERCP could be used repeatedly and effectively for patients who present recurrent obstructive jaundice after ERCP failure.

  3. The Rendezvous Monitoring Display Capabilities of the Rendezvous and Proximity Operations Program

    Science.gov (United States)

    Brazzel, Jack; Spehar, Pete; Clark, Fred; Foster, Chris; Eldridge, Erin

    2013-01-01

    The Rendezvous and Proximity Operations Program (RPOP) is a laptop computer- based relative navigation tool and piloting aid that was developed during the Space Shuttle program. RPOP displays a graphical representation of the relative motion between the target and chaser vehicles in a rendezvous, proximity operations and capture scenario. After being used in over 60 Shuttle rendezvous missions, some of the RPOP display concepts have become recognized as a minimum standard for cockpit displays for monitoring the rendezvous task. To support International Space Station (ISS) based crews in monitoring incoming visiting vehicles, RPOP has been modified to allow crews to compare the Cygnus visiting vehicle s onboard navigated state to processed range measurements from an ISS-based, crew-operated Hand Held Lidar sensor. This paper will discuss the display concepts of RPOP that have proven useful in performing and monitoring rendezvous and proximity operations.

  4. Percutaneous-endoscopic rendezvous procedure for the management of bile duct injuries after cholecystectomy: short- and long-term outcomes.

    Science.gov (United States)

    Schreuder, Anne Marthe; Booij, Klaske A C; de Reuver, Philip R; van Delden, Otto M; van Lienden, Krijn P; Besselink, Marc G; Busch, Olivier R; Gouma, Dirk J; Rauws, Erik A J; van Gulik, Thomas M

    2018-01-19

     Bile duct injury (BDI) remains a daunting complication of laparoscopic cholecystectomy. In patients with complex BDI, a percutaneous-endoscopic rendezvous procedure may be required to establish bile duct continuity. The aim of this study was to assess short- and long-term outcomes of the rendezvous procedure.  All consecutive patients with BDI referred to our tertiary referral center between 1995 and 2016 were analyzed. A rendezvous procedure was performed when endoscopic or radiologic intervention failed, and when deemed feasible by a dedicated multidisciplinary team including hepatopancreaticobiliary surgeons, gastrointestinal endoscopists, and interventional radiologists. Classification of BDI, technical success of the rendezvous procedure, procedure-related adverse events, and outcomes were assessed.  Among a total of 812 patients, rendezvous was performed in 47 (6 %), 31 (66 %) of whom were diagnosed with complete transection of the bile duct (Amsterdam type D/Strasberg type E injury). The primary success rate of rendezvous was 94 % (44 /47 patients). Overall morbidity was 18 % (10 /55 procedures). No life-threatening adverse events or 90-day mortality occurred. After a median follow-up of 40 months (interquartile range 23 - 54 months), rendezvous was the final successful treatment in 26 /47 patients (55 %). In 14 /47 patients (30 %), rendezvous acted as a bridge to surgery, with hepaticojejunostomy being chosen either primarily or secondarily to treat refractory or relapsing stenosis. In experienced hands, rendezvous was a safe procedure, with a long-term success rate of 55 %. When endoscopic or transhepatic interventions fail to restore bile duct continuity in patients with BDI, rendezvous should be considered, either as definitive treatment or as a bridge to elective surgery. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Systematic reviews: guidance relevant for studies of older people.

    Science.gov (United States)

    Shenkin, Susan D; Harrison, Jennifer K; Wilkinson, Tim; Dodds, Richard M; Ioannidis, John P A

    2017-09-01

    Systematic reviews and meta-analyses are increasingly common. This article aims to provide guidance for people conducting systematic reviews relevant to the healthcare of older people. An awareness of these issues will also help people reading systematic reviews to determine whether the results will influence their clinical practice. It is essential that systematic reviews are performed by a team which includes the required technical and clinical expertise. Those performing reviews for the first time should ensure they have appropriate training and support. They must be planned and performed in a transparent and methodologically robust way: guidelines are available. The protocol should be written-and if possible published-before starting the review. Geriatricians will be interested in a table of baseline characteristics, which will help to determine if the studied samples or populations are similar to their patients. Reviews of studies of older people should consider how they will manage issues such as different age cut-offs; non-specific presentations; multiple predictors and outcomes; potential biases and confounders. Systematic reviews and meta-analyses may provide evidence to improve older people's care, or determine where new evidence is required. Newer methodologies, such as meta-analyses of individual level data, network meta-analyses and umbrella reviews, and realist synthesis, may improve the reliability and clinical utility of systematic reviews. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.

  6. A Study on the Influence of Teacher's Verbal Guidance on Pupil's Emotional Functions

    OpenAIRE

    後藤, 靖宏

    2006-01-01

    How do the pupils accept teachers' words of guidance? The purpose of this paper is to study the influence of teachers' verbal guidance on pupil's consciousness ( of emotions and enthusiasm). Although speech (language) is the fastest method of communication between people, it is not the only means of communication. We usually have two means of communication in human interaction, that is verbal communication and nonverbal communication. This is the same with pupil or student guidance. Nonverbal...

  7. Electro-optical rendezvous and docking sensors

    Science.gov (United States)

    Tubbs, David J.; Kesler, Lynn O.; Sirko, Robert J.

    1991-01-01

    Electro-optical sensors provide unique and critical functionality for space missions requiring rendezvous, docking, and berthing. McDonnell Douglas is developing a complete rendezvous and docking system for both manned and unmanned missions. This paper examines our sensor development and the systems and missions which benefit from rendezvous and docking sensors. Simulation results quantifying system performance improvements in key areas are given, with associated sensor performance requirements. A brief review of NASA-funded development activities and the current performance of electro-optical sensors for space applications is given. We will also describe current activities at McDonnell Douglas for a fully functional demonstration to address specific NASA mission needs.

  8. 77 FR 9948 - International Conference on Harmonisation; Guidance on E7 Studies in Support of Special...

    Science.gov (United States)

    2012-02-21

    ...] International Conference on Harmonisation; Guidance on E7 Studies in Support of Special Populations; Geriatrics... Food and Drug Administration (FDA) is announcing the availability of a guidance entitled ``E7 Studies... under the auspices of the International Conference on Harmonisation of Technical Requirements for...

  9. On-Board Rendezvous Targeting for Orion

    Science.gov (United States)

    Weeks, Michael W.; DSouza, Christopher N.

    2010-01-01

    The Orion On-board GNC system is among the most complex ever developed for a space mission. It is designed to operate autonomously (independent of the ground). The rendezvous system in particular was designed to operate on the far side of the moon, and in the case of loss-of-communications with the ground. The vehicle GNC system is designed to retarget the rendezvous maneuvers, given a mission plan. As such, all the maneuvers which will be performed by Orion, have been designed and are being incorporated into the flight code.

  10. Robust Parametric Control of Spacecraft Rendezvous

    Directory of Open Access Journals (Sweden)

    Dake Gu

    2014-01-01

    Full Text Available This paper proposes a method to design the robust parametric control for autonomous rendezvous of spacecrafts with the inertial information with uncertainty. We consider model uncertainty of traditional C-W equation to formulate the dynamic model of the relative motion. Based on eigenstructure assignment and model reference theory, a concise control law for spacecraft rendezvous is proposed which could be fixed through solving an optimization problem. The cost function considers the stabilization of the system and other performances. Simulation results illustrate the robustness and effectiveness of the proposed control.

  11. Randomised study on single stage laparo-endoscopic rendezvous (intra-operative ERCP procedure versus two stage approach (Pre-operative ERCP followed by laparoscopic cholecystectomy for the management of cholelithiasis with choledocholithiasis

    Directory of Open Access Journals (Sweden)

    Manash Ranjan Sahoo

    2014-01-01

    Full Text Available Introduction : The ′Rendezvous′ technique consists of laparoscopic cholecystectomy (LC standards with intra-operative cholangiography followed by endoscopic sphincterotomy. The sphincterotome is driven across the papilla through a guidewire inserted by the transcystic route. In this study, we intended to compare the two methods in a prospective randomised trial. Materials And Methods: From 2005 to 2012, we enrolled 83 patients with a diagnosis of cholecysto-choledocolithiasis. They were randomised into two groups. In ′group-A′,41 patients were treated with two stages management, first by pre-operative endoscopic retrograde cholangiopancreatography (ERCP and common bile duct (CBD clearance and second by LC. In ′group-B′, 42 patients were treated with LC and intra-operative cholangiography; and when diagnosis of choledocholithiasis was confirmed, patients had undergone one stage management of by Laparo-endoscopic Rendezvous technique. Results: In arm-A and arm-B groups, complete CBD clearance was achieved in 29 and 38 patients, respectively. Failure of the treatment in arm-A was 29% and in arm-B was 9.5%. In arm-A, selective CBD cannulation was achieved in 33 cases (80.5% and in arm-B in 39 cases (93%. In arm-Agroup, post-ERCP hyperamylasia was presented in nine patients (22% and severe pancreatitis in five patients (12% versus none of the patients (0% in arm-B group, respectively. Mean post-operative hospital stay in arm-A and arm-B groups are 10.9 and 6.8 days, respectively. Conclusion: One stage laparo-endoscopic rendezvous approach increases selective cannulation of CBD, reduces post-ERCP pancreatitis, reduces days of hospital stay, increases patient′s compliance and prevents unnecessary intervention to CBD.

  12. 76 FR 59142 - Guidance for Industry on Reproductive and Developmental Toxicities-Integrating Study Results To...

    Science.gov (United States)

    2011-09-23

    ... of study results to assess concerns about human reproductive and developmental toxicities. It does... assist that office in processing your requests. See the SUPPLEMENTARY INFORMATION section for electronic access to the guidance document. Submit electronic comments on the guidance to http://www.regulations.gov...

  13. THE RELIGIOUS GUIDANCE FOR PROSTITUTE A Descriptive Study at Palimanan Cirebon

    Directory of Open Access Journals (Sweden)

    Murip Yahya

    2016-02-01

    Full Text Available This study attempts to investigate the implementation of religious guidance for prostitute and its influence to Woman Social Institution Silih Asih in Palimanan, Cirebon. It formulated on four research questions: 1 How is the process of religious guidance in Social Institution Silih Asih; 2 What is the participants’s efforts to achieve the goal of religious guidance; 3 How is the material of religious guidance in Social Institution Silih Asih Palimanan; 4 How is the approach and method of religious guidance applied in Social Institution Silih Asih Palimanan to support and achieve the aim of religious guidance. The study used qualitative-naturalistic, research design with descriptive method. The data were collected through observation, interview, and document analysis. The results of the study show that: 1 there were two stages of religious guidance: identification stage and rehabilitation process; 2 the participants were identified by their age, marital status, education background, parents’ job, and reasons of being prostitute; 3 the materials presented on theoretical and natural materials based on Islam thoughts; 4 the religious guidance used various approaches: experience, habituation, emotional, rational, and holistic.

  14. Occlusal consequence of using average condylar guidance settings: An in vitro study.

    Science.gov (United States)

    Lee, Wonsup; Lim, Young-Jun; Kim, Myung-Joo; Kwon, Ho-Beom

    2017-04-01

    A simplified mounting technique that adopts an average condylar guidance has been advocated. Despite this, the experimental explanation of how average settings differ from individual condylar guidance remains unclear. The purpose of this in vitro study was to examine potential occlusal error by using average condylar guidance settings during nonworking side movement of the articulator. Three-dimensional positions of the nonworking side maxillary first molar at various condylar and incisal settings were traced using a laser displacement sensor attached to the motorized stages with biaxial freedom of movement. To examine clinically relevant occlusal consequences of condylar guidance setting errors, the vertical occlusal error was defined as the vertical-axis positional difference between the average setting trace and the other condylar guidance setting trace. In addition, the respective contribution of the condylar and incisal guidance to the position of the maxillary first molar area was analyzed by multiple regression analysis using the resultant coordinate data. Alteration from individual to average settings led to a positional difference in the maxillary first molar nonworking side movement. When the individual setting was lower than average, vertical occlusal error occurred, which might cause occlusal interference. The vertical occlusal error ranged from -2964 to 1711 μm. In addition, the occlusal effect of incisal guidance was measured as a partial regression coefficient of 0.882, which exceeded the effect of condylar guidance, 0.431. Potential occlusal error as a result of adopting an average condylar guidance setting was observed. The occlusal effect of incisal guidance doubled the effect of condylar guidance. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  15. Multiple NEO Rendezvous Using Solar Sails

    Science.gov (United States)

    Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

    2012-01-01

    Mission concept is to assess the feasibility of using solar sail propulsion to enable a robotic precursor that would survey multiple Near Earth Objects (NEOs) for potential future human visits. Single spacecraft will rendezvous with and image 3 NEOs within 6 years of launch

  16. Rendezvous endoscopic recanalization for complete esophageal obstruction.

    Science.gov (United States)

    Fusco, Stefano; Kratt, Thomas; Gani, Cihan; Stueker, Dietmar; Zips, Daniel; Malek, Nisar P; Goetz, Martin

    2018-03-30

    Complete esophageal obstruction after (chemo)radiation for head and neck cancers is rare. However, inability to swallow one's own saliva strongly inflicts upon quality of life. Techniques for endoscopic recanalization in complete obstruction are not well established. We assessed the efficacy and safety of rendezvous recanalization. We performed a retrospective review of all patients who underwent endoscopic recanalization of complete proximal esophageal obstruction after radiotherapy between January 2009 and June 2016. Technical success was defined as an ability to pass an endoscope across the recanalized lumen, clinical success by changes in the dysphagia score. Adverse events were recorded prospectively. 19 patients with complete obstruction (dysphagia IV°), all of whom had failed at least one trial of conventional dilatation, underwent recanalization by endoscopic rendezvous, a combined approach through a gastrostomy and perorally under fluoroscopic control. Conscious sedation was used in all patients. In 18/19 patients (94.7%), recanalization was technically successful. In 14/18 patients (77.8%), the post-intervention dysphagia score changed to ≤ II. Three patients had their PEG removed. Factors negatively associated with success were obstruction length of 50 mm; and tumor recurrence for long-term success. No severe complications were recorded. Rendezvous recanalization for complete esophageal obstruction is a reliable and safe method to re-establish luminal patency. Differences between technical and clinical success rates highlight the importance of additional functional factors associated with dysphagia. Given the lack of therapeutic alternatives, rendezvous recanalization is a valid option to improve dysphagia.

  17. Rendezvous effects in the diffusion process on bipartite metapopulation networks.

    Science.gov (United States)

    Cao, Lang; Li, Xun; Wang, Bing; Aihara, Kazuyuki

    2011-10-01

    Epidemic outbreaks have been shown to be closely related to the rendezvous-induced transmission of infection, which is caused by casual contact with infected individuals in public gatherings. To investigate rendezvous effects in the spread of infectious diseases, we propose an epidemic model on metapopulation networks bipartite-divided into two sets of location and rendezvous nodes. At a given transition rate γ(kk')(p), each individual transfers from location k to rendezvous p (where rendezvous-induced disease incidence occurs) and thereafter moves to location k'. We find that the eigenstructure of a transition-rate-dependent matrix determines the epidemic threshold condition. Both analytical and numerical results show that rendezvous-induced transmission accelerates the progress of infectious diseases, implying the significance of outbreak control measures including prevention of public gatherings or decentralization of a large-scale rendezvous into downsized ones.

  18. Guidance for Reviewing OCSPP 850.2100 Avian Oral Toxicity Studies Conducted with Passerine Birds

    Science.gov (United States)

    Guidance based on comparison of results from the TG223 validation studies to results from avian acute oral studies previously submitted to EPA for two test chemicals following EPA's 850.2100 (public draft) guidelines.

  19. A modified Rendezvous ERCP technique in duodenal diverticulum.

    Science.gov (United States)

    Odabasi, Mehmet; Yildiz, Mehmet Kamil; Abuoglu, Haci Hasan; Eris, Cengiz; Ozkan, Erkan; Gunay, Emre; Aktekin, Ali; Muftuoglu, Ma Tolga

    2013-11-16

    To postoperative endoscopic retrograde cholangiopancreatography (ERCP) failure, we describe a modified Rendezvous technique for an ERCP in patients operated on for common bile duct stone (CBDS) having a T-tube with retained CBDSs. Five cases operated on for CBDSs and having retained stones with a T-tube were referred from other hospitals located in or around Istanbul city to the ERCP unit at the Haydarpasa Numune Education and Research Hospital. Under sedation anesthesia, a sterile guide-wire was inserted via the T-tube into the common bile duct (CBD) then to the papilla. A guide-wire was held by a loop snare and removed through the mouth. The guide-wire was inserted into the sphincterotome via the duodenoscope from the tip to the handle. The duodenoscope was inserted down to the duodenum with a sphincterotome and a guide-wire in the working channel. With the guidance of a guide-wire, the ERCP and sphincterotomy were successfully performed, the guide-wire was removed from the T-tube, the stones were removed and the CBD was reexamined for retained stones by contrast. An ERCP can be used either preoperatively or postoperatively. Although the success rate in an isolated ERCP treatment ranges from up to 87%-97%, 5%-10% of the patients require two or more ERCP treatments. If a secondary ERCP fails, the clinicians must be ready for a laparoscopic or open exploration. A duodenal diverticulum is one of the most common failures in an ERCP, especially in patients with an intradiverticular papilla. For this small group of patients, an antegrade cannulation via a T-tube can improve the success rate up to nearly 100%. The modified Rendezvous technique is a very easy method and increases the success of postoperative ERCP, especially in patients with large duodenal diverticula and with intradiverticular papilla.

  20. The mobile agent rendezvous problem in the ring

    CERN Document Server

    Kranakis, Evangelos; Marcou, Euripides

    2010-01-01

    Mobile agent computing is being used in fields as diverse as artificial intelligence, computational economics and robotics. Agents' ability to adapt dynamically and execute asynchronously and autonomously brings potential advantages in terms of fault-tolerance, flexibility and simplicity. This monograph focuses on studying mobile agents as modelled in distributed systems research and in particular within the framework of research performed in the distributed algorithms community. It studies the fundamental question of how to achieve rendezvous, the gathering of two or more agents at the same n

  1. Designing the STS-134 Re-Rendezvous: A Preparation for Future Crewed Rendezvous Missions

    Science.gov (United States)

    Stuit, Timothy D.

    2011-01-01

    In preparation to provide the capability for the Orion spacecraft, also known as the Multi-Purpose Crew Vehicle (MPCV), to rendezvous with the International Space Station (ISS) and future spacecraft, a new suite of relative navigation sensors are in development and were tested on one of the final Space Shuttle missions to ISS. The National Aeronautics and Space Administration (NASA) commissioned a flight test of prototypes of the Orion relative navigation sensors on STS-134, in order to test their performance in the space environment during the nominal rendezvous and docking, as well as a re-rendezvous dedicated to testing the prototype sensors following the undocking of the Space Shuttle orbiter at the end of the mission. Unlike the rendezvous and docking at the beginning of the mission, the re-rendezvous profile replicates the newly designed Orion coelliptic approach trajectory, something never before attempted with the shuttle orbiter. Therefore, there were a number of new parameters that needed to be conceived of, designed, and tested for this rerendezvous to make the flight test successful. Additionally, all of this work had to be integrated with the normal operations of the ISS and shuttle and had to conform to the constraints of the mission and vehicles. The result of this work is a separation and rerendezvous trajectory design that would not only prove the design of the relative navigation sensors for the Orion vehicle, but also would serve as a proof of concept for the Orion rendezvous trajectory itself. This document presents the analysis and decision making process involved in attaining the final STS-134 re-rendezvous design.

  2. Tangent Orbital Rendezvous Using Linear Relative Motion with J2 Perturbations

    Directory of Open Access Journals (Sweden)

    Gang Zhang

    2013-01-01

    Full Text Available The tangent-impulse coplanar orbit rendezvous problem is studied based on the linear relative motion for J2-perturbed elliptic orbits. There are three cases: (1 only the first impulse is tangent; (2 only the second impulse is tangent; (3 both impulses are tangent. For a given initial impulse point, the first two problems can be transformed into finding all roots of a single variable function about the transfer time, which can be done by the secant method. The bitangent rendezvous problem requires the same solution for the first two problems. By considering the initial coasting time, the bitangent rendezvous solution is obtained with a difference function. A numerical example for two coplanar elliptic orbits with J2 perturbations is given to verify the efficiency of these proposed techniques.

  3. Flocking and rendezvous in distributed robotics

    CERN Document Server

    Francis, Bruce A

    2016-01-01

    This brief describes the coordinated control of groups of robots using only sensory input – and no direct external commands. Furthermore, each robot employs the same local strategy, i.e., there are no leaders, and the text also deals with decentralized control, allowing for cases in which no single robot can sense all the others. One can get intuition for the problem from the natural world, for example, flocking birds. How do they achieve and maintain their flying formation? Recognizing their importance as the most basic coordination tasks for mobile robot networks, the brief details flocking and rendezvous. They are shown to be physical illustrations of emergent behaviors with global consensus arising from local interactions. The authors extend the consideration of these fundamental ideas to describe their operation in flying robots and prompt readers to pursue further research in the field.  Flocking and Rendezvous in Distributed Robotics will provide graduate students a firm grounding in the subject, w...

  4. Automated rendezvous and capture development infrastructure

    Science.gov (United States)

    Bryan, Thomas C.; Roe, Fred; Coker, Cynthia

    1992-01-01

    The facilities at Marshall Space Flight Center and JSC to be utilized to develop and test an autonomous rendezvous and capture (ARC) system are described. This includes equipment and personnel facility capabilities to devise, develop, qualify, and integrate ARC elements and subsystems into flight programs. Attention is given to the use of a LEO test facility, the current concept and unique system elements of the ARC, and the options available to develop ARC technology.

  5. Hyperbolic Rendezvous at Mars: Risk Assessments and Mitigation Strategies

    Science.gov (United States)

    Jedrey, Ricky; Landau, Damon; Whitley, Ryan

    2015-01-01

    Given the current interest in the use of flyby trajectories for human Mars exploration, a key requirement is the capability to execute hyperbolic rendezvous. Hyperbolic rendezvous is used to transport crew from a Mars centered orbit, to a transiting Earth bound habitat that does a flyby. Representative cases are taken from future potential missions of this type, and a thorough sensitivity analysis of the hyperbolic rendezvous phase is performed. This includes early engine cutoff, missed burn times, and burn misalignment. A finite burn engine model is applied that assumes the hyperbolic rendezvous phase is done with at least two burns.

  6. Effect of flashlight guidance on manual ventilation performance in cardiopulmonary resuscitation: A randomized controlled simulation study.

    Science.gov (United States)

    Kim, Ji Hoon; Beom, Jin Ho; You, Je Sung; Cho, Junho; Min, In Kyung; Chung, Hyun Soo

    2018-01-01

    Several auditory-based feedback devices have been developed to improve the quality of ventilation performance during cardiopulmonary resuscitation (CPR), but their effectiveness has not been proven in actual CPR situations. In the present study, we investigated the effectiveness of visual flashlight guidance in maintaining high-quality ventilation performance. We conducted a simulation-based, randomized, parallel trial including 121 senior medical students. All participants were randomized to perform ventilation during 2 minutes of CPR with or without flashlight guidance. For each participant, we measured mean ventilation rate as a primary outcome and ventilation volume, inspiration velocity, and ventilation interval as secondary outcomes using a computerized device system. Mean ventilation rate did not significantly differ between flashlight guidance and control groups (P = 0.159), but participants in the flashlight guidance group exhibited significantly less variation in ventilation rate than participants in the control group (Pguidance group. Our results demonstrate that flashlight guidance is effective in maintaining a constant ventilation rate and interval. If confirmed by further studies in clinical practice, flashlight guidance could be expected to improve the quality of ventilation performed during CPR.

  7. Breathing guidance in radiation oncology and radiology: A systematic review of patient and healthy volunteer studies

    International Nuclear Information System (INIS)

    Pollock, Sean; Keall, Paul; Keall, Robyn

    2015-01-01

    Purpose: The advent of image-guided radiation therapy has led to dramatic improvements in the accuracy of treatment delivery in radiotherapy. Such advancements have highlighted the deleterious impact tumor motion can have on both image quality and radiation treatment delivery. One approach to reducing tumor motion irregularities is the use of breathing guidance systems during imaging and treatment. These systems aim to facilitate regular respiratory motion which in turn improves image quality and radiation treatment accuracy. A review of such research has yet to be performed; it was therefore their aim to perform a systematic review of breathing guidance interventions within the fields of radiation oncology and radiology. Methods: From August 1–14, 2014, the following online databases were searched: Medline, Embase, PubMed, and Web of Science. Results of these searches were filtered in accordance to a set of eligibility criteria. The search, filtration, and analysis of articles were conducted in accordance with preferred reporting items for systematic reviews and meta-analyses. Reference lists of included articles, and repeat authors of included articles, were hand-searched. Results: The systematic search yielded a total of 480 articles, which were filtered down to 27 relevant articles in accordance to the eligibility criteria. These 27 articles detailed the intervention of breathing guidance strategies in controlled studies assessing its impact on such outcomes as breathing regularity, image quality, target coverage, and treatment margins, recruiting either healthy adult volunteers or patients with thoracic or abdominal lesions. In 21/27 studies, significant (p < 0.05) improvements from the use of breathing guidance were observed. Conclusions: There is a trend toward the number of breathing guidance studies increasing with time, indicating a growing clinical interest. The results found here indicate that further clinical studies are warranted that quantify the

  8. Breathing guidance in radiation oncology and radiology: A systematic review of patient and healthy volunteer studies

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, Sean, E-mail: sean.pollock@sydney.edu.au; Keall, Paul [Radiation Physics Laboratory, University of Sydney, Sydney 2050 (Australia); Keall, Robyn [Central School of Medicine, University of Sydney, Sydney 2050, Australia and Hammond Care, Palliative Care and Supportive Care Service, Greenwich 2065 (Australia)

    2015-09-15

    Purpose: The advent of image-guided radiation therapy has led to dramatic improvements in the accuracy of treatment delivery in radiotherapy. Such advancements have highlighted the deleterious impact tumor motion can have on both image quality and radiation treatment delivery. One approach to reducing tumor motion irregularities is the use of breathing guidance systems during imaging and treatment. These systems aim to facilitate regular respiratory motion which in turn improves image quality and radiation treatment accuracy. A review of such research has yet to be performed; it was therefore their aim to perform a systematic review of breathing guidance interventions within the fields of radiation oncology and radiology. Methods: From August 1–14, 2014, the following online databases were searched: Medline, Embase, PubMed, and Web of Science. Results of these searches were filtered in accordance to a set of eligibility criteria. The search, filtration, and analysis of articles were conducted in accordance with preferred reporting items for systematic reviews and meta-analyses. Reference lists of included articles, and repeat authors of included articles, were hand-searched. Results: The systematic search yielded a total of 480 articles, which were filtered down to 27 relevant articles in accordance to the eligibility criteria. These 27 articles detailed the intervention of breathing guidance strategies in controlled studies assessing its impact on such outcomes as breathing regularity, image quality, target coverage, and treatment margins, recruiting either healthy adult volunteers or patients with thoracic or abdominal lesions. In 21/27 studies, significant (p < 0.05) improvements from the use of breathing guidance were observed. Conclusions: There is a trend toward the number of breathing guidance studies increasing with time, indicating a growing clinical interest. The results found here indicate that further clinical studies are warranted that quantify the

  9. Multi-Agent Rendezvousing with a Finite Set of Candidate Rendezvous Points

    NARCIS (Netherlands)

    Fang, J.; Morse, A. S.; Cao, M.

    2008-01-01

    The discrete multi-agent rendezvous problem we consider in this paper is concerned with a specified set of points in the plane, called “dwell-points,” and a set of mobile autonomous agents with limited sensing range. Each agent is initially positioned at some dwell-point, and is able to determine

  10. State of Data Guidance in Journal Policies: A Case Study in Oncology

    Directory of Open Access Journals (Sweden)

    Deborah H. Charbonneau

    2015-06-01

    Full Text Available This article reports the results of a study examining the state of data guidance provided to authors by 50 oncology journals. The purpose of the study was the identification of data practices addressed in the journals’ policies. While a number of studies have examined data sharing practices among researchers, little is known about how journals address data sharing. Thus, what was discovered through this study has practical implications for journal publishers, editors, and researchers. The findings indicate that journal publishers should provide more meaningful and comprehensive data guidance to prospective authors. More specifically, journal policies requiring data sharing, should direct researchers to relevant data repositories, and offer better metadata consultation to strengthen existing journal policies. By providing adequate guidance for authors, and helping investigators to meet data sharing mandates, scholarly journal publishers can play a vital role in advancing access to research data.

  11. Guidance on assessing the methodological and reporting quality of toxicologically relevant studies: A scoping review.

    Science.gov (United States)

    Samuel, Gbeminiyi O; Hoffmann, Sebastian; Wright, Robert A; Lalu, Manoj Mathew; Patlewicz, Grace; Becker, Richard A; DeGeorge, George L; Fergusson, Dean; Hartung, Thomas; Lewis, R Jeffrey; Stephens, Martin L

    2016-01-01

    Assessments of methodological and reporting quality are critical to adequately judging the credibility of a study's conclusions and to gauging its potential reproducibility. To aid those seeking to assess the methodological or reporting quality of studies relevant to toxicology, we conducted a scoping review of the available guidance with respect to four types of studies: in vivo and in vitro, (quantitative) structure-activity relationships ([Q]SARs), physico-chemical, and human observational studies. Our aims were to identify the available guidance in this diverse literature, briefly summarize each document, and distill the common elements of these documents for each study type. In general, we found considerable guidance for in vivo and human studies, but only one paper addressed in vitro studies exclusively. The guidance for (Q)SAR studies and physico-chemical studies was scant but authoritative. There was substantial overlap across guidance documents in the proposed criteria for both methodological and reporting quality. Some guidance documents address toxicology research directly, whereas others address preclinical research generally or clinical research and therefore may not be fully applicable to the toxicology context without some translation. Another challenge is the degree to which assessments of methodological quality in toxicology should focus on risk of bias - as in clinical medicine and healthcare - or be broadened to include other quality measures, such as confirming the identity of test substances prior to exposure. Our review is intended primarily for those in toxicology and risk assessment seeking an entry point into the extensive and diverse literature on methodological and reporting quality applicable to their work. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Usage and User Experience of Communication before and during Rendezvous

    Science.gov (United States)

    Colbert, Martin

    2005-01-01

    This paper reports a field evaluation of the mobile phone as a "package" of device and services. The evaluation compares 44 university students' usage and user experience of communication before and during rendezvous. During a rendezvous (en route), students rated many aspects of the experience of phone use less favourably than before a rendezvous…

  13. Rendezvous and Docking Strategy for Crewed Segment of the Asteroid Redirect Mission

    Science.gov (United States)

    Hinkel, Heather D.; Cryan, Scott P.; D'Souza, Christopher; Dannemiller, David P.; Brazzel, Jack P.; Condon, Gerald L.; Othon, William L.; Williams, Jacob

    2014-01-01

    This paper will describe the overall rendezvous, proximity operations and docking (RPOD) strategy in support of the Asteroid Redirect Crewed Mission (ARCM), as part of the Asteroid Redirect Mission (ARM). The focus of the paper is on the crewed mission phase of ARM, starting with the establishment of Orion in the Distant Retrograde Orbit (DRO) and ending with docking to the Asteroid Redirect Vechicle (ARV). The paper will detail the sequence of maneuvers required to execute the rendezvous and proximity operations mission phases along with the on-board navigation strategies, including the final approach phase. The trajectories to be considered will include target vehicles in a DRO. The paper will also discuss the sensor requirements for rendezvous and docking and the various trade studies associated with the final sensor selection. Building on the sensor requirements and trade studies, the paper will include a candidate sensor concept of operations, which will drive the selection of the sensor suite; concurrently, it will be driven by higher level requirements on the system, such as crew timeline constraints and vehicle consummables. This paper will address how many of the seemingly competing requirements will have to be addressed to create a complete system and system design. The objective is to determine a sensor suite and trajectories that enable Orion to successfully rendezvous and dock with a target vehicle in trans lunar space. Finally, the paper will report on the status of a NASA action to look for synergy within RPOD, across the crewed and robotic asteroid missions.

  14. Remedial Investigation/Feasibility Study (RI/FS) process, elements and techniques guidance

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    This manual provides detailed guidance on Remedial Investigation/Feasibility Studies (RI/FSs) conducted pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) at Department of Energy (DOE) facilities. The purpose of the RI/FS, to assess the risk posed by a hazardous waste site and to determine the best way to reduce that risk, and its structure (site characterization, risk assessment, screening and detailed analysis of alternatives, etc.) is defined in the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) and further explained in the Environmental Protection Agency`s (EPA`s) Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA (Interim Final) 540/G-89/004, OSWER Directive 9355.3-01, October 1988. Though issued in 1988, the EPA guidance remains an excellent source of information on the conduct and structure of an RI/FS. This document makes use of supplemental RI/FS-related guidance that EPA has developed since its initial document was issued in 1988, incorporates practical lessons learned in more than 12 years of experience in CERCLA hazardous site remediation, and drawing on those lessons, introduces the Streamlined Approach For Environmental Restoration (SAFER), developed by DOE as a way to proceed quickly and efficiently through the RI/FS process at DOE facilities. Thus as its title implies, this guidance is intended to describe in detail the process and component elements of an RI/FS, as well as techniques to manage the RI/FS effectively.

  15. Comparison of EUS-guided rendezvous and precut papillotomy techniques for biliary access (with videos).

    Science.gov (United States)

    Dhir, Vinay; Bhandari, Suryaprakash; Bapat, Mukta; Maydeo, Amit

    2012-02-01

    Precut papillotomy after failed bile duct cannulation is associated with an increased risk of pancreatitis. EUS-guided rendezvous drainage is a novel alternative technique, but there are no data comparing this approach with precut papillotomy. To evaluate the safety and efficacy of EUS-guided rendezvous drainage of the bile duct and compare its outcome with that of precut papillotomy. Retrospective study. Tertiary care referral center. Consecutive patients with distal bile duct obstruction, in whom selective cannulation of the bile duct at ERCP failed after 5 attempts with a guidewire and sphincterotome, underwent an EUS-guided rendezvous procedure. The outcomes were compared with those in a historical cohort of patients who underwent precut papillotomy. Patients in whom selective cannulation failed underwent EUS-guided rendezvous drainage by use of the short wire technique or precut papillotomy by use of the Erlangen papillotome. At EUS, after the extrahepatic bile duct was punctured with a 19-gauge needle, a hydrophilic angled-tip guidewire 260 cm long was passed in an antegrade manner across the papilla into the duodenum. The echoendoscope was then exchanged for a duodenoscope, which was introduced alongside the EUS-placed guidewire. The transpapillary guidewire was retrieved through its biopsy channel, and accessories were passed over the wire to perform the requisite endotherapy. Comparison of the rates of technical success and complications between patients treated by the EUS-guided rendezvous and those treated by precut papillotomy techniques. Treatment success was defined as completion of the requisite endotherapy in one treatment session. Treatment success was significantly higher for the EUS-guided rendezvous (57/58 patients) than for those undergoing precut papillotomy technique (130/144 patients) (98.3% vs 90.3%; P = .03). There was no significant difference in the rate of procedural complications between the EUS and precut papillotomy techniques (3

  16. An integrated autonomous rendezvous and docking system architecture using Centaur modern avionics

    Science.gov (United States)

    Nelson, Kurt

    1991-01-01

    The avionics system for the Centaur upper stage is in the process of being modernized with the current state-of-the-art in strapdown inertial guidance equipment. This equipment includes an integrated flight control processor with a ring laser gyro based inertial guidance system. This inertial navigation unit (INU) uses two MIL-STD-1750A processors and communicates over the MIL-STD-1553B data bus. Commands are translated into load activation through a Remote Control Unit (RCU) which incorporates the use of solid state relays. Also, a programmable data acquisition system replaces separate multiplexer and signal conditioning units. This modern avionics suite is currently being enhanced through independent research and development programs to provide autonomous rendezvous and docking capability using advanced cruise missile image processing technology and integrated GPS navigational aids. A system concept was developed to combine these technologies in order to achieve a fully autonomous rendezvous, docking, and autoland capability. The current system architecture and the evolution of this architecture using advanced modular avionics concepts being pursued for the National Launch System are discussed.

  17. Rendezvous, proximity operations and capture quality function deployment report

    Science.gov (United States)

    Lamkin, Stephen L. (Editor)

    1991-01-01

    Rendezvous, Proximity Operations, and Capture (RPOC) is a missions operations area which is extremely important to present and future space initiatives and must be well planned and coordinated. To support this, a study team was formed to identify a specific plan of action using the Quality Function Deployment (QFD) process. This team was composed of members from a wide spectrum of engineering and operations organizations which are involved in the RPOC technology area. The key to this study's success is an understanding of the needs of potential programmatic customers and the technology base available for system implementation. To this end, the study team conducted interviews with a variety of near term and future programmatic customers and technology development sponsors. The QFD activity led to a thorough understanding of the needs of these customers in the RPOC area, as well as the relative importance of these needs.

  18. Rendezvous, proximity operations and capture quality function deployment report

    Science.gov (United States)

    Lamkin, Stephen L.

    1991-12-01

    Rendezvous, Proximity Operations, and Capture (RPOC) is a missions operations area which is extremely important to present and future space initiatives and must be well planned and coordinated. To support this, a study team was formed to identify a specific plan of action using the Quality Function Deployment (QFD) process. This team was composed of members from a wide spectrum of engineering and operations organizations which are involved in the RPOC technology area. The key to this study's success is an understanding of the needs of potential programmatic customers and the technology base available for system implementation. To this end, the study team conducted interviews with a variety of near term and future programmatic customers and technology development sponsors. The QFD activity led to a thorough understanding of the needs of these customers in the RPOC area, as well as the relative importance of these needs.

  19. Pedagogical guidance for consumer studies reflected in the South

    African Journals Online (AJOL)

    user

    Umalusi (the Council for Quality Assurance in. General and ... government executed a national audit on teaching. In 1997, the ... refers to the methods, activities, principles or practices that ...... based learning in pre-service Consumer Studies.

  20. 78 FR 73199 - Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs...

    Science.gov (United States)

    2013-12-05

    ... exposure measures is suitable for documenting BE (e.g., transdermal delivery systems and certain rectal and... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-D-1464] Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs Submitted...

  1. 75 FR 36425 - Guidance for Industry and Food and Drug Administration Staff; In Vitro Diagnostic Studies...

    Science.gov (United States)

    2010-06-25

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2007-D-0076] (formerly Docket No. 2007D-0387) Guidance for Industry and Food and Drug Administration Staff; In Vitro Diagnostic Studies--Frequently Asked Questions; Availability AGENCY: Food and Drug Administration, HHS...

  2. An Action Research Study: Using Classroom Guidance Lessons to Teach Middle School Students about Sexual Harassment

    Science.gov (United States)

    Bates, Rebecca C.

    2006-01-01

    This article describes a three-part classroom guidance lesson that teaches middle school students the definition of sexual harassment, the difference between flirting and sexual harassment, and the harmful effects of sexual harassment. An action research study evaluated the effectiveness of the lessons in decreasing referrals for sexual harassment…

  3. 75 FR 18497 - Guidance on Simultaneous Transmission Import Limit Studies for the Northwest Region; Notice of...

    Science.gov (United States)

    2010-04-12

    ... updated market power analyses associated with their market based rate authorizations, which are due in... Conference ``Guidance on Simultaneous Transmission Import Limit Studies.'' To view the archive of the... Northwest region transmission owners and their pending updated market power analyses. Interested persons...

  4. Study on the Reduced Traffic Congestion Method Based on Dynamic Guidance Information

    Science.gov (United States)

    Li, Shu-Bin; Wang, Guang-Min; Wang, Tao; Ren, Hua-Ling; Zhang, Lin

    2018-05-01

    This paper studies how to generate the reasonable information of travelers’ decision in real network. This problem is very complex because the travelers’ decision is constrained by different human behavior. The network conditions can be predicted by using the advanced dynamic OD (Origin-Destination, OD) estimation techniques. Based on the improved mesoscopic traffic model, the predictable dynamic traffic guidance information can be obtained accurately. A consistency algorithm is designed to investigate the travelers’ decision by simulating the dynamic response to guidance information. The simulation results show that the proposed method can provide the best guidance information. Further, a case study is conducted to verify the theoretical results and to draw managerial insights into the potential of dynamic guidance strategy in improving traffic performance. Supported by National Natural Science Foundation of China under Grant Nos. 71471104, 71771019, 71571109, and 71471167; The University Science and Technology Program Funding Projects of Shandong Province under Grant No. J17KA211; The Project of Public Security Department of Shandong Province under Grant No. GATHT2015-236; The Major Social and Livelihood Special Project of Jinan under Grant No. 20150905

  5. Evaluation of Hanau's formula in determination of lateral condylar guidance: A clinical research study

    Science.gov (United States)

    Bhawsar, Sanjay Vasant; Marathe, Ashlesha Subhash; Ansari, Sadekh Abdul

    2015-01-01

    Statement of Problem: The accuracy and reliability of the methods used for programming the semi-adjustable articulators determine the accuracy in occlusion. The current recommended average settings using the Hanau's formula commonly used by clinicians is questionable, and thus reassessment is needed. This study was carried out to evaluate and compare the lateral condylar guidance: (1) Using the Hanau's formula and the computerized jaw tracking device (Kinesiograph). (2) On the right and left sides using both these methods. Materials and Methods: A total of 20 completely edentulous patients (14 male and 6 females) within 40–60 years of age were selected. Jaw relation was recorded followed by face bow transfer. Extraoral Gothic arch tracing was recorded; three protrusive records were obtained and condylar guidance was calculated. Lateral condylar guidance was then calculated using Hanau's formula, followed by the computerized jaw tracking device. A comparative evaluation was done of the obtained values. The same investigator worked with each of the study participants for the purpose of standardization. Results: The lateral condylar guidance values obtained using the Hanau's formula ranged from 14 to 17° while those obtained using the computerized K7 jaw tracking device ranged from 8 to 40°. Bennett angle values, obtained using the jaw tracking device and Hanau's formula showed statistically significant differences (P 0.05). Conclusion: Based on the results, dentist and dental technicians should consider reassessing the current recommended average settings and use of the Hanau's formula for programming the semi-adjustable articulators. PMID:26929535

  6. Expert system isssues in automated, autonomous space vehicle rendezvous

    Science.gov (United States)

    Goodwin, Mary Ann; Bochsler, Daniel C.

    1987-01-01

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

  7. Combined antegrade and retrograde ureteral stenting: the rendezvous technique

    International Nuclear Information System (INIS)

    Macri, A.; Magno, C.; Certo, A.; Basile, A.; Scuderi, G.; Crescenti, F.; Famulari, C.

    2005-01-01

    Ureteral stenting is a routine procedure in endourology. To increase the success rate in difficult cases, it may be helpful to use the rendezvous technique, a combined antegrade and retrograde approach. We performed 16 urological rendezvous in 11 patients with ureteral strictures or urologic lesions. The combined approach was successful in all patients, without morbidity or mortality. In our experience the rendezvous technique increased the success rate of antegrade ureteral stenting from 78.6 to 88.09% (p>0.05). This procedure is a valid option in case of failure of conventional ureteral stenting

  8. Rendezvous missions with minimoons from L1

    Science.gov (United States)

    Chyba, M.; Haberkorn, T.; Patterson, G.

    2014-07-01

    We propose to present asteroid capture missions with the so-called minimoons. Minimoons are small asteroids that are temporarily captured objects on orbits in the Earth-Moon system. It has been suggested that, despite their small capture probability, at any time there are one or two meter diameter minimoons, and progressively greater numbers at smaller diameters. The minimoons orbits differ significantly from elliptical orbits which renders a rendezvous mission more challenging, however they offer many advantages for such missions that overcome this fact. First, they are already on geocentric orbits which results in short duration missions with low Delta-v, this translates in cost efficiency and low-risk targets. Second, beside their close proximity to Earth, an advantage is their small size since it provides us with the luxury to retrieve the entire asteroid and not only a sample of material. Accessing the interior structure of a near-Earth satellite in its morphological context is crucial to an in-depth analysis of the structure of the asteroid. Historically, 2006 RH120 is the only minimoon that has been detected but work is ongoing to determine which modifications to current observation facilities is necessary to provide detection algorithm capabilities. In the event that detection is successful, an efficient algorithm to produce a space mission to rendezvous with the detected minimoon is highly desirable to take advantage of this opportunity. This is the main focus of our work. For the design of the mission we propose the following. The spacecraft is first placed in hibernation on a Lissajoux orbit around the liberation point L1 of the Earth-Moon system. We focus on eight-shaped Lissajoux orbits to take advantage of the stability properties of their invariant manifolds for our transfers since the cost to minimize is the spacecraft fuel consumption. Once a minimoon has been detected we must choose a point on its orbit to rendezvous (in position and velocities

  9. Autonomous rendezvous and capture development infrastructure

    Science.gov (United States)

    Bryan, Thomas C.; Roe, Fred; Coker, Cindy; Nelson, Pam; Johnson, B.

    1991-01-01

    In the development of the technology for autonomous rendezvous and docking, key infrastructure capabilities must be used for effective and economical development. This involves facility capabilities, both equipment and personnel, to devise, develop, qualify, and integrate ARD elements and subsystems into flight programs. One effective way of reducing technical risks in developing ARD technology is the use of the ultimate test facility, using a Shuttle-based reusable free-flying testbed to perform a Technology Demonstration Test Flight which can be structured to include a variety of additional sensors, control schemes, and operational approaches. This conceptual testbed and flight demonstration will be used to illustrate how technologies and facilities at MSFC can be used to develop and prove an ARD system.

  10. Rendezvous, un juego de Lewis Carroll

    Directory of Open Access Journals (Sweden)

    José Manuel Sánchez Muñoz

    2011-10-01

    Full Text Available Todos en mayor o menor medida asociamos el nombre de Lewis Carrolla la literatura, sobre todo a la de temática infantil, con títulos a sus espaldas como Alicia en el País de las Maravillas, Alicia a través del espejo, o La Caza del Snark. Pero además de literato, Lewis Carrol fue un hombre con bastantes inquietudes en torno a la matemática, la lógica y el pensamiento filosófico. Pero no todo el mundo es conocedor de su faceta como creativo en el campo de los juegos. Rendezvous es una de sus más sorprendentes invenciones,un juego de inteligencia para todos los públicos, cuyas directrices hacen de él un entretenimiento bastante original.

  11. Pilot Study of a New Nonradioactive Surgical Guidance Technology for Locating Nonpalpable Breast Lesions.

    Science.gov (United States)

    Cox, Charles E; Garcia-Henriquez, Norbert; Glancy, M Jordan; Whitworth, Pat; Cox, John M; Themar-Geck, Melissa; Prati, Ronald; Jung, Michelle; Russell, Scott; Appleton, Kristie; King, Jeff; Shivers, Steven C

    2016-06-01

    The current technique for locating nonpalpable breast lesions is wire localization (WL). Radioactive seed localization and intraoperative ultrasound were developed to improve difficulties with WL. The SAVI SCOUT surgical guidance system was developed to improve these methods. The SCOUT system is a non-radioactive, FDA-cleared medical device that uses electromagnetic wave technology to provide real-time guidance during excisional breast procedures. Consenting patients underwent localization and excision using an implantable electromagnetic wave reflective device (reflector) and a detector handpiece with a console. Using image guidance, the reflector was placed up to 7 days before the surgical procedure. The primary end points of the study were successful reflector placement, localization, and retrieval. The secondary end points were percentage of clear margins, reexcision rates, days of placement before excision, and physician comparison with WL. This study analyzed 50 patients. The reflectors were placed under mammographic guidance (n = 18, 36 %) or ultrasound guidance (n = 32, 64 %). Of the 50 patients, 10 (20 %) underwent excisional biopsy and 40 (80 %) had a lumpectomy. The lesion and reflector were successfully removed in all 50 patients, and no adverse events occurred. Of the 41 patients who had in situ and/or invasive carcinoma identified, 38 (93 %) had clear margins and 3 (7 %) were recommended for reexcision. These data suggest that the SCOUT system is safe and effective for guiding the excision of nonpalpable breast lesions and a viable alternative to standard localization options. A larger prospective, multi-institution trial of SCOUT currently is underway to validate these findings.

  12. 75 FR 3471 - International Conference on Harmonisation; Guidance on M3(R2) Nonclinical Safety Studies for the...

    Science.gov (United States)

    2010-01-21

    ...] International Conference on Harmonisation; Guidance on M3(R2) Nonclinical Safety Studies for the Conduct of... the availability of a guidance entitled ``M3(R2) Nonclinical Safety Studies for the Conduct of Human... auspices of the International Conference on Harmonisation of Technical Requirements for Registration of...

  13. Analysis of costs for compliance with Federal Radiation Protection Guidance for Occupational Exposure. Volume 2: case study analysis of the impacts of proposed radiation protection guidance for workers

    International Nuclear Information System (INIS)

    1983-11-01

    This report contains the writeups of case studies conducted in support of an effort to estimate costs and economic impacts of proposed Federal Radiation Protection Guidance for Occupational Exposures. The purpose of the case studies was to develop background information on representative organizations necessary to determine the impact of the proposed guidelines on selected industries. This information was used, together with other data, to estimate the aggregate costs of compliance with the proposed guidelines. The cost estimates are contained in a companion report

  14. Guidance, Navigation, and Control Techniques and Technologies for Active Satellite Removal

    Science.gov (United States)

    Ortega Hernando, Guillermo; Erb, Sven; Cropp, Alexander; Voirin, Thomas; Dubois-Matra, Olivier; Rinalducci, Antonio; Visentin, Gianfranco; Innocenti, Luisa; Raposo, Ana

    2013-09-01

    This paper shows an internal feasibility analysis to de- orbit a non-functional satellite of big dimensions by the Technical Directorate of the European Space Agency ESA. The paper focuses specifically on the design of the techniques and technologies for the Guidance, Navigation, and Control (GNC) system of the spacecraft mission that will capture the satellite and ultimately will de-orbit it on a controlled re-entry.The paper explains the guidance strategies to launch, rendezvous, close-approach, and capture the target satellite. The guidance strategy uses chaser manoeuvres, hold points, and collision avoidance trajectories to ensure a safe capture. It also details the guidance profile to de-orbit it in a controlled re-entry.The paper continues with an analysis of the required sensing suite and the navigation algorithms to allow the homing, fly-around, and capture of the target satellite. The emphasis is placed around the design of a system to allow the rendezvous with an un-cooperative target, including the autonomous acquisition of both the orbital elements and the attitude of the target satellite.Analysing the capture phase, the paper provides a trade- off between two selected capture systems: the net and the tentacles. Both are studied from the point of view of the GNC system.The paper analyses as well the advanced algorithms proposed to control the final compound after the capture that will allow the controlled de-orbiting of the assembly in a safe place in the Earth.The paper ends proposing the continuation of this work with the extension to the analysis of the destruction process of the compound in consecutive segments starting from the entry gate to the rupture and break up.

  15. 77 FR 9946 - Draft Guidance for Industry on Drug Interaction Studies-Study Design, Data Analysis, Implications...

    Science.gov (United States)

    2012-02-21

    ... industry entitled ``Drug Interaction Studies--Study Design, Data Analysis, Implications for Dosing, and... data analysis in the context of identifying potential drug interactions. The guidance also addresses... Studies--Study Design, Data Analysis, and Implications for Dosing and Labeling.'' Comments were received...

  16. Near-Earth Asteroid Rendezvous: mission overview

    Science.gov (United States)

    Cheng, A. F.; Santo, A. G.; Heeres, K. J.; Landshof, J. A.; Farquhar, R. W.; Gold, R. E.; Lee, S. C.

    1997-10-01

    The Near-Earth Asteroid Rendezvous (NEAR) mission, the first launch of NASA's Discovery Program, will be the first mission to orbit an asteroid. NEAR will make the first comprehensive scientific measurements of an asteroid's surface composition, geology, physical properties, and internal structure. NEAR launched successfully on February 17, 1996, aboard a Delta II-7925. It will orbit the 20-km-diameter near-Earth asteroid 433 Eros for about 1 year, at a minimum orbit radius of about 35 km from the center of the asteroid. The NEAR is a solar-powered, three-axis stabilized spacecraft with a launch mass including propellant of 805 kg. NEAR uses X band telemetry to the NASA Deep Space Network, with the data rates at Eros up to 8.8 kbits/s using a 34-m High Efficiency (HEF) dish, and up to 26.5 kbits/s using a 70-m dish. A solid-state recorder is accommodated with a memory capacity of 1.8 Gbytes. Attitude control is to 1.7 mrad, line-of-sight pointing stability is within 50 μrad over 1 s, and post processing attitude knowledge is within 50 μrad. NEAR accommodates 56 kg of instruments and provides them with 84 W. The instruments are a multispectral imager (MSI), a near-infrared spectrograph (NIS), an X ray/gamma ray spectrometer (XRS/GRS), a magnetometer (MAG), and a laser rangefinder (NLR), while a radio science (RS) investigation uses the coherent X band transponder. NEAR will make a flyby of the C-type asteroid 253 Mathilde in June 1997 and will rendezvous with 433 Eros in February 1999. It will execute an initial slow flyby of Eros, with a flyby speed of 5 m/s and a closest approach distance of 500 km. Subsequently, its orbit will be lowered to 35 km. The NEAR Mission Operations Center and the Science Data Center are at the Johns Hopkins Applied Physics Laboratory. The Science Data Center will maintain the entire NEAR data set on-line, and data from all instruments can be accessed by every member of the NEAR Science Team. Data, including images, are released over

  17. EUS-guided biliary drainage by using a standardized approach for malignant biliary obstruction: rendezvous versus direct transluminal techniques (with videos).

    Science.gov (United States)

    Khashab, Mouen A; Valeshabad, Ali Kord; Modayil, Rani; Widmer, Jessica; Saxena, Payal; Idrees, Mehak; Iqbal, Shahzad; Kalloo, Anthony N; Stavropoulos, Stavros N

    2013-11-01

    EUS-guided biliary drainage (EGBD) can be performed via direct transluminal or rendezvous techniques. It is unknown how both techniques compare in terms of efficacy and adverse events. To describe outcomes of EGBD performed by using a standardized approach and compare outcomes of rendezvous and transluminal techniques. Retrospective analysis of prospectively collected data. Two tertiary-care centers. Consecutive jaundiced patients with distal malignant biliary obstruction who underwent EGBD after failed ERCP between July 2006 and December 2012 were included. EGBD by using a standardized algorithm. Technical success, clinical success, and adverse events. During the study period, 35 patients underwent EGBD (rendezvous n = 13, transluminal n = 20). Technical success was achieved in 33 patients (94%), and clinical success was attained in 32 of 33 patients (97.0%). The mean postprocedure bilirubin level was 1.38 mg/dL in the rendezvous group and 1.33 mg/dL in the transluminal group (P = .88). Similarly, length of hospital stay was not different between groups (P = .23). There was no significant difference in adverse event rate between rendezvous and transluminal groups (15.4% vs 10%; P = .64). Long-term outcomes were comparable between groups, with 1 stent migration in the rendezvous group at 62 days and 1 stent occlusion in the transluminal group at 42 days after EGBD. Retrospective analysis, small number of patients, and selection bias. EGBD is safe and effective when the described standardized approach is used. Stent occlusion is not common during long-term follow-up. Both rendezvous and direct transluminal techniques seem to be equally effective and safe. The latter approach is a reasonable alternative to rendezvous EGBD. Copyright © 2013. Published by Mosby, Inc.

  18. Ecological risk assessment guidance for preparation of remedial investigation/feasibility study work plans

    International Nuclear Information System (INIS)

    Pentecost, E.D.; Vinikour, W.S.

    1993-08-01

    This guidance document (1) provides instructions on preparing the components of an ecological work plan to complement the overall site remedial assessment investigation/feasibility study (RI/FS) work plan and (2) directs the user on how to implement ecological tasks identified in the plan. Under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended by the Superfired Amendments and Reauthorization Act of 1986 (SARA), an RI/FS work plan win have to be developed as part of the site-remediation scoping the process. Specific guidance on the RI/FS process and the preparation of work plans has been developed by the US Environmental Protection Agency (EPA 1988a). This document provides guidance to US Department of Energy (DOE) staff and contractor personnel for incorporation of ecological information into environmental remediation planning and decision making at CERCLA sites. An overview analysis of early ecological risk assessment methods (i.e., in the 1980s) at Superfund sites was conducted by the EPA (1989a). That review provided a perspective of attention given to ecological issues in some of the first RI/FS studies. By itself, that reference is of somewhat limited value; it does, however, establish a basis for comparison of past practices in ecological risk with current, more refined methods

  19. Closed Loop Guidance Trade Study for Space Launch System Block-1B Vehicle

    Science.gov (United States)

    Von der Porten, Paul; Ahmad, Naeem; Hawkins, Matt

    2018-01-01

    NASA is currently building the Space Launch System (SLS) Block-1 launch vehicle for the Exploration Mission 1 (EM-1) test flight. The design of the next evolution of SLS, Block-1B, is well underway. The Block-1B vehicle is more capable overall than Block-1; however, the relatively low thrust-to-weight ratio of the Exploration Upper Stage (EUS) presents a challenge to the Powered Explicit Guidance (PEG) algorithm used by Block-1. To handle the long burn durations (on the order of 1000 seconds) of EUS missions, two algorithms were examined. An alternative algorithm, OPGUID, was introduced, while modifications were made to PEG. A trade study was conducted to select the guidance algorithm for future SLS vehicles. The chosen algorithm needs to support a wide variety of mission operations: ascent burns to LEO, apogee raise burns, trans-lunar injection burns, hyperbolic Earth departure burns, and contingency disposal burns using the Reaction Control System (RCS). Additionally, the algorithm must be able to respond to a single engine failure scenario. Each algorithm was scored based on pre-selected criteria, including insertion accuracy, algorithmic complexity and robustness, extensibility for potential future missions, and flight heritage. Monte Carlo analysis was used to select the final algorithm. This paper covers the design criteria, approach, and results of this trade study, showing impacts and considerations when adapting launch vehicle guidance algorithms to a broader breadth of in-space operations.

  20. Condylar guidance: correlation between protrusive interocclusal record and panoramic radiographic image: a pilot study.

    Science.gov (United States)

    Tannamala, Pavan Kumar; Pulagam, Mahesh; Pottem, Srinivas R; Swapna, B

    2012-04-01

    The purpose of this study was to compare the sagittal condylar angles set in the Hanau articulator by use of a method of obtaining an intraoral protrusive record to those angles found using a panoramic radiographic image. Ten patients, free of signs and symptoms of temporomandibular disorder and with intact dentition were selected. The dental stone casts of the subjects were mounted on a Hanau articulator with a springbow and poly(vinyl siloxane) interocclusal records. For all patients, the protrusive records were obtained when the mandible moved forward by approximately 6 mm. All procedures for recording, mounting, and setting were done in the same session. The condylar guidance angles obtained were tabulated. A panoramic radiographic image of each patient was made with the Frankfurt horizontal plane parallel to the floor of the mouth. Tracings of the radiographic images were made. The horizontal reference line was marked by joining the orbitale and porion. The most superior and most inferior points of the curvatures were identified. These two lines were connected by a straight line representing the mean curvature line. Angles made by the intersection of the mean curvature line and the horizontal reference line were measured. The results were subjected to statistical analysis with a significance level of p record method. The mean condylar guidance angle between the right and left side by both the methods was not statistically significant. The comparison of mean condylar guidance angles between the right side of the protrusive record method and the right side of the panoramic radiographic method and the left side of the protrusive record method and the left side of the panoramic radiographic method (p= 0.071 and p= 0.057, respectively) were not statistically significant. Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used in programming semi-adjustable articulators. © 2012

  1. Dynamic Eco-Driving Speed Guidance at Signalized Intersections: Multivehicle Driving Simulator Based Experimental Study

    Directory of Open Access Journals (Sweden)

    Peng Chen

    2018-01-01

    Full Text Available Variations in vehicle fuel consumption and gas emissions are usually associated with changes in cruise speed and the aggressiveness of drivers’ acceleration/deceleration, especially at traffic signals. In an attempt to enhance vehicle fuel efficiency on arterials, this study developed a dynamic eco-driving speed guidance strategy (DESGS using real-time signal timing and vehicle positioning information in a connected vehicle (CV environment. DESGS mainly aims to optimize the fuel/emission speed profiles for vehicles approaching signalized intersections. An optimization-based rolling horizon and a dynamic programming approach were proposed to track the optimal guided velocity for individual vehicles along the travel segment. In addition, a vehicle specific power (VSP based approach was integrated into DESGS to estimate the fuel consumption and CO2 emissions. To evaluate the effectiveness of the overall strategy, 15 experienced drivers were recruited to participate in interactive speed guidance experiments using multivehicle driving simulators. It was found that compared to vehicles without speed guidance, those with DESGS had a significantly reduced number of stops and approximately 25% less fuel consumption and CO2 emissions.

  2. Interstellar rendezvous missions employing fission propulsion systems

    International Nuclear Information System (INIS)

    Lenard, Roger X.; Lipinski, Ronald J.

    2000-01-01

    There has been a conventionally held nostrum that fission system specific power and energy content is insufficient to provide the requisite high accelerations and velocities to enable interstellar rendezvous missions within a reasonable fraction of a human lifetime. As a consequence, all forms of alternative mechanisms that are not yet, and may never be technologically feasible, have been proposed, including laser light sails, fusion and antimatter propulsion systems. In previous efforts, [Lenard and Lipinski, 1999] the authors developed an architecture that employs fission power to propel two different concepts: one, an unmanned probe, the other a crewed vehicle to Alpha Centauri within mission times of 47 to 60 years. The first portion of this paper discusses employing a variant of the ''Forward Resupply Runway'' utilizing fission systems to enable both high accelerations and high final velocities necessary for this type of travel. The authors argue that such an architecture, while expensive, is considerably less expensive and technologically risky than other technologically advanced concepts, and, further, provides the ability to explore near-Earth stellar systems out to distances of 8 light years or so. This enables the ability to establish independent human societies which can later expand the domain of human exploration in roughly eight light-year increments even presuming that no further physics or technology breakthroughs or advances occur. In the second portion of the paper, a technology requirement assessment is performed. The authors argue that reasonable to extensive extensions to known technology could enable this revolutionary capability

  3. Visual Control for Multirobot Organized Rendezvous.

    Science.gov (United States)

    Lopez-Nicolas, G; Aranda, M; Mezouar, Y; Sagues, C

    2012-08-01

    This paper addresses the problem of visual control of a set of mobile robots. In our framework, the perception system consists of an uncalibrated flying camera performing an unknown general motion. The robots are assumed to undergo planar motion considering nonholonomic constraints. The goal of the control task is to drive the multirobot system to a desired rendezvous configuration relying solely on visual information given by the flying camera. The desired multirobot configuration is defined with an image of the set of robots in that configuration without any additional information. We propose a homography-based framework relying on the homography induced by the multirobot system that gives a desired homography to be used to define the reference target, and a new image-based control law that drives the robots to the desired configuration by imposing a rigidity constraint. This paper extends our previous work, and the main contributions are that the motion constraints on the flying camera are removed, the control law is improved by reducing the number of required steps, the stability of the new control law is proved, and real experiments are provided to validate the proposal.

  4. Developing guidelines for incorporating managing demand into WSDOT planning and programming: transportation demand management guidance for corridor planning studies.

    Science.gov (United States)

    2016-02-01

    The Washington State Department of Transportation (WSDOT) regional planning programs address current and forecasted deficiencies of State highways through the conduct of corridor studies. This Guidance for the conduct of corridor planning studies is ...

  5. Autonomous rendezvous and docking operations of unmanned expendable cargo transfer vehicles (e.g. Centaur) with Space Station Freedom

    Science.gov (United States)

    Emmet, Brian R.

    1991-01-01

    This paper describes the results of the feasibility study using Centaur or other CTV's to deliver payloads to the Space Station Freedom (SSF). During this study was examined the requirements upon unmanned cargo transfer stages (including Centaur) for phasing, rendezvous, proximity operations and docking/berthing (capture).

  6. The Data Transfer Kit: A geometric rendezvous-based tool for multiphysics data transfer

    International Nuclear Information System (INIS)

    Slattery, S. R.; Wilson, P. P. H.; Pawlowski, R. P.

    2013-01-01

    The Data Transfer Kit (DTK) is a software library designed to provide parallel data transfer services for arbitrary physics components based on the concept of geometric rendezvous. The rendezvous algorithm provides a means to geometrically correlate two geometric domains that may be arbitrarily decomposed in a parallel simulation. By repartitioning both domains such that they have the same geometric domain on each parallel process, efficient and load balanced search operations and data transfer can be performed at a desirable algorithmic time complexity with low communication overhead relative to other types of mapping algorithms. With the increased development efforts in multiphysics simulation and other multiple mesh and geometry problems, generating parallel topology maps for transferring fields and other data between geometric domains is a common operation. The algorithms used to generate parallel topology maps based on the concept of geometric rendezvous as implemented in DTK are described with an example using a conjugate heat transfer calculation and thermal coupling with a neutronics code. In addition, we provide the results of initial scaling studies performed on the Jaguar Cray XK6 system at Oak Ridge National Laboratory for a worse-case-scenario problem in terms of algorithmic complexity that shows good scaling on 0(1 x 104) cores for topology map generation and excellent scaling on 0(1 x 105) cores for the data transfer operation with meshes of O(1 x 109) elements. (authors)

  7. Current status of laparoendoscopic rendezvous in the treatment of cholelithiasis with concomitant choledocholithiasis.

    Science.gov (United States)

    Baloyiannis, Ioannis; Tzovaras, George

    2015-06-25

    The current evidence in favor of the laparoendoscopic rendezvous is promising and demonstrates the main advantages of this technique in regard to shorter hospital stay and selective cannulation of the common bile duct (CBD), avoiding thus the inadvertent cannulation of the pancreatic duct. In addition, in the rendezvous technique the contrast medium is not injected retrogradely as during the traditional endoscopic retrograde cholangiopancreatography (ERCP), when the medium accidentally could be injected under pressure into the pancreatic duct. The RV technique minimizes that risk. Both these main advantages of the RV technique over the classic ERCP, are related with a significant lower incidence of hyperamylasemia and post-ERCP pancreatitis, compared with the traditional two stage procedure. Choledocholithiasis is present in 10% to 15% of patients undergoing cholecystectomy. To date, the ideal management of CBD stones remains controversial. Prospective randomized trials have shown that laparoscopic management of the CBD stones, as a single stage procedure, is the most efficient and cost effective method of treatment. Laparoendoscopic rendezvous has been proposed as an alternative single stage approach. Several studies have shown the effective use of this technique in the treatment of CBD stones by improving patient compliance and clinical results including shorter hospital stay, higher success rate and less cost. The current evidence about the use of this technique presented in this review article is promising and demonstrates the main advantages of the procedure.

  8. The Data Transfer Kit: A geometric rendezvous-based tool for multiphysics data transfer

    Energy Technology Data Exchange (ETDEWEB)

    Slattery, S. R.; Wilson, P. P. H. [Department of Engineering Physics, University of Wisconsin - Madison, 1500 Engineering Dr., Madison, WI 53706 (United States); Pawlowski, R. P. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185 (United States)

    2013-07-01

    The Data Transfer Kit (DTK) is a software library designed to provide parallel data transfer services for arbitrary physics components based on the concept of geometric rendezvous. The rendezvous algorithm provides a means to geometrically correlate two geometric domains that may be arbitrarily decomposed in a parallel simulation. By repartitioning both domains such that they have the same geometric domain on each parallel process, efficient and load balanced search operations and data transfer can be performed at a desirable algorithmic time complexity with low communication overhead relative to other types of mapping algorithms. With the increased development efforts in multiphysics simulation and other multiple mesh and geometry problems, generating parallel topology maps for transferring fields and other data between geometric domains is a common operation. The algorithms used to generate parallel topology maps based on the concept of geometric rendezvous as implemented in DTK are described with an example using a conjugate heat transfer calculation and thermal coupling with a neutronics code. In addition, we provide the results of initial scaling studies performed on the Jaguar Cray XK6 system at Oak Ridge National Laboratory for a worse-case-scenario problem in terms of algorithmic complexity that shows good scaling on 0(1 x 104) cores for topology map generation and excellent scaling on 0(1 x 105) cores for the data transfer operation with meshes of O(1 x 109) elements. (authors)

  9. Endoskopisk ultralydvejledt rendezvous til intern drænage ved galdevejsobstruktion

    DEFF Research Database (Denmark)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem

    2015-01-01

    Endoscopic ultrasound guided rendezvous for biliary drainage Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic...

  10. Transluminal recanalization of chronic total occlusion of radial artery using rendezvous technique: a case report and literature review.

    Science.gov (United States)

    Arabi, Mohammad; Ahmed, Ishtiaq; Qattan, Nabeel

    2014-01-01

    Although endovascular management of lower extremity peripheral arterial disease (PAD) is well studied, little information exists regarding endovascular treatment of critical upper limb ischemia. We report a case of transluminal recanalization of right radial artery chronic total occlusion (CTO) using rendezvous technique in a patient with critical hand ischemia and dry gangrene of the right index finger.

  11. Transluminal Recanalization of Chronic Total Occlusion of Radial Artery Using Rendezvous Technique: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Mohammad Arabi

    2014-01-01

    Full Text Available Although endovascular management of lower extremity peripheral arterial disease (PAD is well studied, little information exists regarding endovascular treatment of critical upper limb ischemia. We report a case of transluminal recanalization of right radial artery chronic total occlusion (CTO using rendezvous technique in a patient with critical hand ischemia and dry gangrene of the right index finger.

  12. NEP for a Kuiper Belt Object rendezvous mission

    International Nuclear Information System (INIS)

    Lipinski, Ronald J.; Lenard, Roger X.; Wright, Steven A.; Houts, Michael G.; Patton, Bruce; Poston, David I.

    2000-01-01

    Kuiper Belt Objects (KBOs) are a recently-discovered set of solar system bodies which lie at about the orbit of Pluto (40 AU) out to about 100 astronomical units (AU). There are estimated to be about 100,000 KBOs with a diameter greater than 100 km. KBOs are postulated to be composed of the pristine material which formed our solar system and may even have organic materials in them. A detailed study of KBO size, orbit distribution, structure, and surface composition could shed light on the origins of the solar system and perhaps even on the origin of life in our solar system. A rendezvous mission including a lander would be needed to perform chemical analysis of the surface and sub-surface composition of KBOs. These requirements set the size of the science probe at around a ton. Mission analyses show that a fission-powered system with an electric thruster could rendezvous at 40 AU in about 13.0 years with a total DV of 46 km/s. It would deliver a 1000-kg science payload while providing ample onboard power for relaying data back to earth. The launch mass of the entire system (power, thrusters, propellant, navigation, communication, structure, science payload, etc.) would be 7984 kg if it were placed into an earth-escape trajectory (C=0). Alternatively, the system could be placed into a 700-km earth orbit with more propellant, yielding a total mass in LEO of 8618 kg, and then spiral out of earth orbit to arrive at the KBO in 14.3 years. To achieve this performance, a fission power system with 100 kW of electrical power and a total mass (reactor, shield, conversion, and radiator) of about 2350 kg. Three possible configurations are proposed: (1) a UZrH-fueled, NaK-cooled reactor with a steam Rankine conversion system, (2) a UN-fueled gas-cooled reactor with a recuperated Brayton conversion system, and (3) a UN-fueled heatpipe-cooled reactor with a recuperated Brayton conversion system. (Boiling and condensation in the Rankine system is a technical risk at present.) All

  13. NEP for a Kuiper Belt Object Rendezvous Mission

    International Nuclear Information System (INIS)

    HOUTS, MICHAEL G.; LENARD, ROGER X.; LIPINSKI, RONALD J.; PATTON, BRUCE; POSTON, DAVID I.; WRIGHT, STEVEN A.

    1999-01-01

    Kuiper Belt Objects (KBOs) are a recently-discovered set of solar system bodies which lie at about the orbit of Pluto (40 AU) out to about 100 astronomical units (AU). There are estimated to be about 100,000 KBOS with a diameter greater than 100 km. KBOS are postulated to be composed of the pristine material which formed our solar system and may even have organic materials in them. A detailed study of KBO size, orbit distribution, structure, and surface composition could shed light on the origins of the solar system and perhaps even on the origin of life in our solar system. A rendezvous mission including a lander would be needed to perform chemical analysis of the surface and sub-surface composition of KBOS. These requirements set the size of the science probe at around a ton. Mission analyses show that a fission-powered system with an electric thruster could rendezvous at 40 AU in about 13.0 years with a total ΔV of 46 krnk. It would deliver a 1000-kg science payload while providing ample onboard power for relaying data back to earth. The launch mass of the entire system (power, thrusters, propellant, navigation, communication, structure, science payload, etc.) would be 7984 kg if it were placed into an earth-escape trajectory (C=O). Alternatively, the system could be placed into a 700-km earth orbit with more propellant,yielding a total mass in LEO of 8618 kg, and then spiral out of earth orbit to arrive at the KBO in 14.3 years. To achieve this performance, a fission power system with 100 kW of electrical power and a total mass (reactor, shield, conversion, and radiator) of about 2350 kg. Three possible configurations are proposed: (1) a UZrH-fueled, NaK-cooled reactor with a steam Rankine conversion system, (2) a UN-fueled gas-cooled reactor with a recuperated Brayton conversion system, and (3) a UN-fueled heatpipe-cooled reactor with a recuperated Brayton conversion system. (Boiling and condensation in the Rankine system is a technical risk at present.) All

  14. Two-phase framework for optimal multi-target Lambert rendezvous

    OpenAIRE

    Bang, Jun; Ahn, Jaemyung

    2017-01-01

    This paper proposes a two-phase framework to solve an optimal multi-target Lambert rendezvous problem. The first phase solves a series of single-target rendezvous problems for all departure-arrival object pairs to generate the elementary solutions, which provides candidate rendezvous trajectories (elementary solutions). The second phase formulates a variant of traveling salesman problem (TSP) using the elementary solutions prepared in the first phase and determines the best rendezvous sequenc...

  15. Automated space vehicle control for rendezvous proximity operations

    Science.gov (United States)

    Lea, Robert N.

    1988-01-01

    Rendezvous during the unmanned space exploration missions, such as a Mars Rover/Sample Return will require a completely automatic system from liftoff to docking. A conceptual design of an automated rendezvous, proximity operations, and docking system is being implemented and validated at the Johnson Space Center (JSC). The emphasis is on the progress of the development and testing of a prototype system for control of the rendezvous vehicle during proximity operations that is currently being developed at JSC. Fuzzy sets are used to model the human capability of common sense reasoning in decision making tasks and such models are integrated with the expert systems and engineering control system technology to create a system that performs comparably to a manned system.

  16. Robust H∞ Control for Spacecraft Rendezvous with a Noncooperative Target

    Directory of Open Access Journals (Sweden)

    Shu-Nan Wu

    2013-01-01

    Full Text Available The robust H∞ control for spacecraft rendezvous with a noncooperative target is addressed in this paper. The relative motion of chaser and noncooperative target is firstly modeled as the uncertain system, which contains uncertain orbit parameter and mass. Then the H∞ performance and finite time performance are proposed, and a robust H∞ controller is developed to drive the chaser to rendezvous with the non-cooperative target in the presence of control input saturation, measurement error, and thrust error. The linear matrix inequality technology is used to derive the sufficient condition of the proposed controller. An illustrative example is finally provided to demonstrate the effectiveness of the controller.

  17. Usefulness of combined percutaneous-endoscopic rendezvous techniques after failed therapeutic endoscopic retrograde cholangiography in the era of endoscopic ultrasound guided rendezvous.

    Science.gov (United States)

    Yang, Min Jae; Kim, Jin Hong; Hwang, Jae Chul; Yoo, Byung Moo; Kim, Soon Sun; Lim, Sun Gyo; Won, Je Hwan

    2017-12-01

    The rendezvous approach is a salvage technique after failure of endoscopic retrograde cholangiography (ERC). In certain circumstances, percutaneous-endoscopic rendezvous (PE-RV) is preferred, and endoscopic ultrasound-guided rendezvous (EUS-RV) is difficult to perform. We aimed to evaluate PE-RV outcomes, describe the PE-RV techniques, and identify potential indications for PE-RV over EUS-RV.Retrospective analysis was conducted of a prospectively designed ERC database between January 2005 and December 2016 at a tertiary referral center including cases where PE-RV was used as a salvage procedure after ERC failure.During the study period, PE-RV was performed in 42 cases after failed therapeutic ERC; 15 had a surgically altered enteric anatomy. The technical success rate of PE-RV was 92.9% (39/42), with a therapeutic success rate of 88.1% (37/42). Potential indications for PE-RV over EUS-RV were identified in 23 cases, and either PE-RV or EUS-RV could have effectively been used in 19 cases. Endoscopic bile duct access was successfully achieved with PE-RV in 39 cases with accessible biliary orifice using one of PE-RV cannulation techniques (classic, n = 11; parallel, n = 19; and adjunctive maneuvers, n = 9).PE-RV uses a unique technology and has clinical indications that distinguish it from EUS-RV. Therefore, PE-RV can still be considered a useful salvage technique for the treatment of biliary obstruction after ERC failure.

  18. Balloon sheaths for gastrointestinal guidance and access: a preliminary phantom study

    International Nuclear Information System (INIS)

    He, Xu; Shin, Ji Hoon; Kim, Hyo Cheol; Woo, Cheol Woong; Woo, Sung Ha; Choi, Won Chan; Kim, Jong Gyu; Lim, Jin Oh; Kim, Tae Hyung; Yoon, Chang Jin; Song, Ho Young; Kang, Wee Chang

    2005-01-01

    We wanted to evaluate the feasibility and usefulness of a newly designed balloon sheath for gastrointestinal guidance and access by conducting a phantom study. The newly designed balloon sheath consisted of an introducer sheath and a supporting balloon. A coil catheter was advanced over a guide wire into two gastroduodenal phantoms (one was with stricture and one was without stricture); group I was without a balloon sheath, group II was with a deflated balloon sheath, and groups III and IV were with an inflated balloon and with the balloon in the fundus and body, respectively. Each test was performed for 2 minutes and it was repeated 10 times in each group by two researchers, and the positions reached by the catheter tip were recorded. Both researchers had better performances with both phantoms in order of group IV, III, II and I. In group IV, both researchers advanced the catheter tip through the fourth duodenal segment in both the phantoms. In group I, however, the catheter tip never reached the third duodenal segment in both the phantoms by both the researchers. The numeric values for the four study groups were significantly different for both the phantoms (ρ < 0.001). A significant difference was also found between group III and IV for both phantoms (ρ < 0.001). The balloon sheath seems to be feasible for clinical use, and it has good clinical potential for gastrointestinal guidance and access, particularly when the inflated balloon is placed in the gastric body

  19. Correlation of the Condylar Guidance Obtained by Protrusive Interocclusal Record and Panoramic Radiographs in Completely Edentulous Patients: An in Vivo Study

    Directory of Open Access Journals (Sweden)

    Khyati Shah

    2014-01-01

    Results: The results showed statistically significant difference between the condylar guidance values obtained from Orthopantomograph (Radiograph and the condylar guidance values obtained at the stage of jaw relation. Conclusion: Within the limitations of the study, it can be concluded that the condylar guidance values obtained from the Radiographs were higher than those obtained at the stage of jaw relation recording stage.

  20. Greater occipital nerve infiltration under MR guidance. Feasibility study and preliminary results

    International Nuclear Information System (INIS)

    Kastler, Adrian; Perolat, Romain; Kastler, Bruno; Maindet-Dominici, Caroline; Fritz, Jan; Benabid, Alim Louis; Chabardes, Stephan; Krainik, Alexandre

    2018-01-01

    To assess the feasibility of greater occipital nerve (GON) intermediate site infiltration with MRI guidance. Eleven consecutive patients suffering from chronic refractory cranio-facial pain who underwent 16 GON infiltrations were included in this prospective study. All of the procedures were performed on an outpatient basis in the research facility of our institution, with a 1.5 T scanner. The fatty space between inferior obliquus and semispinalis muscles at C1-C2 level was defined as the target. Technical success was defined as the ability to accurately inject the products at the target, assessed by post-procedure axial and sagittal proton density-weighted sequences. Clinical success was defined as a 50% pain decrease at 1 month. Technical success was 100%. GON was depicted in 6/11 cases on planning MRI sequences. Mean duration of procedure was 22.5 min (range 16-41). Clinical success was obtained in 7/11 included patients (63.6%) with a mean self-reported improvement of 78%. Interventional MR-guidance for GON infiltration is a feasible technique offering similar results to an already established effective procedure. It may appear as a useful tool in specific populations, such as young patients and repeat infiltrations, and should be considered in these settings. (orig.)

  1. Greater occipital nerve infiltration under MR guidance. Feasibility study and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Kastler, Adrian; Perolat, Romain [Grenoble Alpes University Hospital, Neuroradiology and MRI Unit, Grenoble (France); CLINATEC Research Facility, LETI, CEA Grenoble (France); Kastler, Bruno [Paris V University, Adult Radiology Department, Necker Hospital, Paris (France); Maindet-Dominici, Caroline [Grenoble Alpes University Hospital, Pain Management Unit, Grenoble (France); Fritz, Jan [The Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Benabid, Alim Louis [CLINATEC Research Facility, LETI, CEA Grenoble (France); Chabardes, Stephan [CLINATEC Research Facility, LETI, CEA Grenoble (France); Grenoble Alpes University Hospital, Neurosurgery Unit, Grenoble (France); Krainik, Alexandre [Grenoble Alpes University Hospital, Neuroradiology and MRI Unit, Grenoble (France)

    2018-02-15

    To assess the feasibility of greater occipital nerve (GON) intermediate site infiltration with MRI guidance. Eleven consecutive patients suffering from chronic refractory cranio-facial pain who underwent 16 GON infiltrations were included in this prospective study. All of the procedures were performed on an outpatient basis in the research facility of our institution, with a 1.5 T scanner. The fatty space between inferior obliquus and semispinalis muscles at C1-C2 level was defined as the target. Technical success was defined as the ability to accurately inject the products at the target, assessed by post-procedure axial and sagittal proton density-weighted sequences. Clinical success was defined as a 50% pain decrease at 1 month. Technical success was 100%. GON was depicted in 6/11 cases on planning MRI sequences. Mean duration of procedure was 22.5 min (range 16-41). Clinical success was obtained in 7/11 included patients (63.6%) with a mean self-reported improvement of 78%. Interventional MR-guidance for GON infiltration is a feasible technique offering similar results to an already established effective procedure. It may appear as a useful tool in specific populations, such as young patients and repeat infiltrations, and should be considered in these settings. (orig.)

  2. Test Results for the Automated Rendezvous and Capture System

    Science.gov (United States)

    Cruzen, Craig; Dabney, Richard; Lomas, James

    1999-01-01

    The Automated Rendezvous and Capture (AR&C) system was designed and tested at NASA's Marshall Space Flight Center (MSFC) to demonstrate technologies and mission strategies for automated rendezvous and docking of spacecraft in Earth orbit, The system incorporates some of the latest innovations in Global Positioning, System space navigation, laser sensor technologies and automated mission sequencing algorithms. The system's initial design and integration was completed in 1998 and has undergone testing at MSFC. This paper describes the major components of the AR&C system and presents results from the official system tests performed in MSFC's Flight Robotics Laboratory with digital simulations and hardware in the loop tests. The results show that the AR&C system can safely and reliably perform automated rendezvous and docking missions in the absence of system failures with 100 percent success. When system failures are included, the system uses its automated collision avoidance maneuver logic to recover in a safe manner. The primary objective of the AR&C project is to prove that by designing a safe and robust automated system, mission operations cost can be reduced by decreasing the personnel required for mission design, preflight planning and training required for crewed rendezvous and docking missions.

  3. Ternary and hybrid controllers for the rendezvous of unicycles

    NARCIS (Netherlands)

    Jafarian, Matin

    2015-01-01

    This paper presents the rendezvous (consensus) of the orientations and average positions of a group of unicycles. We assume that the decentralized controllers designed for consensus of the average positions take only values in the set {-1; 0; +1}. In addition, we introduce a hybrid controller to

  4. Optimization of Spacecraft Rendezvous and Docking using Interval Analysis

    NARCIS (Netherlands)

    Van Kampen, E.; Chu, Q.P.; Mulder, J.A.

    2010-01-01

    This paper applies interval optimization to the fixed-time multiple impulse rendezvous and docking problem. Current methods for solving this type of optimization problem include for example genetic algorithms and gradient based optimization. Unlike these methods, interval methods can guarantee that

  5. Global guidance on environmental life cycle impact assessment indicators: Progress and case study

    DEFF Research Database (Denmark)

    Frischknecht, Rolf; Fantke, Peter; Tschümperlin, Laura

    2016-01-01

    Purpose The life cycle impact assessment (LCIA) guidance flagship project of the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) Life Cycle Initiative aims at providing global guidance and building scientific consensus on environmental LCIA in...

  6. Short rendezvous missions for advanced Russian human spacecraft

    Science.gov (United States)

    Murtazin, Rafail F.; Budylov, Sergey G.

    2010-10-01

    The two-day stay of crew in a limited inhabited volume of the Soyuz-TMA spacecraft till docking to ISS is one of the most stressful parts of space flight. In this paper a number of possible ways to reduce the duration of the free flight phase are considered. The duration is defined by phasing strategy that is necessary for reduction of the phase angle between the chaser and target spacecraft. Some short phasing strategies could be developed. The use of such strategies creates more comfortable flight conditions for crew thanks to short duration and additionally it allows saving spacecraft's life support resources. The transition from the methods of direct spacecraft rendezvous using one orbit phasing (first flights of " Vostok" and " Soyuz" vehicles) to the currently used methods of two-day rendezvous mission can be observed in the history of Soviet manned space program. For an advanced Russian human rated spacecraft the short phasing strategy is recommended, which can be considered as a combination between the direct and two-day rendezvous missions. The following state of the art technologies are assumed available: onboard accurate navigation; onboard computations of phasing maneuvers; launch vehicle with high accuracy injection orbit, etc. Some operational requirements and constraints for the strategies are briefly discussed. In order to provide acceptable phase angles for possible launch dates the experience of the ISS altitude profile control can be used. As examples of the short phasing strategies, the following rendezvous missions are considered: direct ascent, short mission with the phasing during 3-7 orbits depending on the launch date (nominal or backup). For each option statistical modeling of the rendezvous mission is fulfilled, as well as an admissible phase angle range, accuracy of target state vector and addition fuel consumption coming out of emergency is defined. In this paper an estimation of pros and cons of all options is conducted.

  7. The Next Generation Advanced Video Guidance Sensor: Flight Heritage and Current Development

    Science.gov (United States)

    Howard, Richard T.; Bryan, Thomas C.

    2009-01-01

    The Next Generation Advanced Video Guidance Sensor (NGAVGS) is the latest in a line of sensors that have flown four times in the last 10 years. The NGAVGS has been under development for the last two years as a long-range proximity operations and docking sensor for use in an Automated Rendezvous and Docking (AR&D) system. The first autonomous rendezvous and docking in the history of the U.S. Space Program was successfully accomplished by Orbital Express, using the Advanced Video Guidance Sensor (AVGS) as the primary docking sensor. That flight proved that the United States now has a mature and flight proven sensor technology for supporting Crew Exploration Vehicles (CEV) and Commercial Orbital Transport Systems (COTS) Automated Rendezvous and Docking (AR&D). NASA video sensors have worked well in the past: the AVGS used on the Demonstration of Autonomous Rendezvous Technology (DART) mission operated successfully in "spot mode" out to 2 km, and the first generation rendezvous and docking sensor, the Video Guidance Sensor (VGS), was developed and successfully flown on Space Shuttle flights in 1997 and 1998. This paper presents the flight heritage and results of the sensor technology, some hardware trades for the current sensor, and discusses the needs of future vehicles that may rendezvous and dock with the International Space Station (ISS) and other Constellation vehicles. It also discusses approaches for upgrading AVGS to address parts obsolescence, and concepts for minimizing the sensor footprint, weight, and power requirements. In addition, the testing of the various NGAVGS development units will be discussed along with the use of the NGAVGS as a proximity operations and docking sensor.

  8. Review of Technical Studies in the United States in Support of Burnup Credit Regulatory Guidance

    International Nuclear Information System (INIS)

    Wagner, John C.; Parks, Cecil V.; Mueller, Don; Gauld, Ian C.

    2010-01-01

    Taking credit for the reduction in reactivity associated with fuel depletion can enable more cost-effective, higher-density storage, transport, disposal, and reprocessing of spent nuclear fuel (SNF) while maintaining sufficient subcritical margin to establish an adequate safety basis. Consequently, there continues to be considerable interest in the United States (U.S.), as well as internationally, in the increased use of burnup credit in SNF operations, particularly related to storage, transport, and disposal of commercial SNF. This interest has motivated numerous technical studies related to the application of burnup credit, both domestically and internationally, as well as the design of SNF storage, transport and disposal systems that rely on burnup credit for maintaining subcriticality. Responding to industry requests and needs, the U.S. Nuclear Regulatory Commission (NRC) initiated a burnup credit research program in 1999, with support from the Oak Ridge National Laboratory (ORNL), to develop regulatory guidance and the supporting technical bases for allowing and expanding the use of burnup credit in pressurized-water reactor SNF storage and transport applications. Although this NRC research program has not been continuous since its inception, considerable progress has been achieved in many key areas in terms of increased understanding of relevant phenomena and issues, availability of relevant information and data, and subsequently updated regulatory guidance for expanded use of burnup credit. This paper reviews technical studies performed by ORNL for the U.S. NRC burnup credit research program. Examples of topics include reactivity effects associated with reactor operating characteristics, fuel assembly characteristics, burnable absorbers, control rods, spatial burnup distributions, cooling time, and assembly misloading; methods and data for validation of isotopic composition predictions; methods and data for validation of criticality calculations; and

  9. Multi-Sensor Testing for Automated Rendezvous and Docking Sensor Testing at the Flight Robotics Laboratory

    Science.gov (United States)

    Brewster, L.; Johnston, A.; Howard, R.; Mitchell, J.; Cryan, S.

    2007-01-01

    The Exploration Systems Architecture defines missions that require rendezvous, proximity operations, and docking (RPOD) of two spacecraft both in Low Earth Orbit (LEO) and in Low Lunar Orbit (LLO). Uncrewed spacecraft must perform automated and/or autonomous rendezvous, proximity operations and docking operations (commonly known as AR&D). The crewed missions may also perform rendezvous and docking operations and may require different levels of automation and/or autonomy, and must provide the crew with relative navigation information for manual piloting. The capabilities of the RPOD sensors are critical to the success of the Exploration Program. NASA has the responsibility to determine whether the Crew Exploration Vehicle (CEV) contractor proposed relative navigation sensor suite will meet the requirements. The relatively low technology readiness level of AR&D relative navigation sensors has been carried as one of the CEV Project's top risks. The AR&D Sensor Technology Project seeks to reduce the risk by the testing and analysis of selected relative navigation sensor technologies through hardware-in-the-loop testing and simulation. These activities will provide the CEV Project information to assess the relative navigation sensors maturity as well as demonstrate test methods and capabilities. The first year of this project focused on a series of"pathfinder" testing tasks to develop the test plans, test facility requirements, trajectories, math model architecture, simulation platform, and processes that will be used to evaluate the Contractor-proposed sensors. Four candidate sensors were used in the first phase of the testing. The second phase of testing used four sensors simultaneously: two Marshall Space Flight Center (MSFC) Advanced Video Guidance Sensors (AVGS), a laser-based video sensor that uses retroreflectors attached to the target vehicle, and two commercial laser range finders. The multi-sensor testing was conducted at MSFC's Flight Robotics Laboratory (FRL

  10. Multi-Sensor Testing for Automated Rendezvous and Docking Sensor Testing at the Flight Robotics Lab

    Science.gov (United States)

    Brewster, Linda L.; Howard, Richard T.; Johnston, A. S.; Carrington, Connie; Mitchell, Jennifer D.; Cryan, Scott P.

    2008-01-01

    The Exploration Systems Architecture defines missions that require rendezvous, proximity operations, and docking (RPOD) of two spacecraft both in Low Earth Orbit (LEO) and in Low Lunar Orbit (LLO). Uncrewed spacecraft must perform automated and/or autonomous rendezvous, proximity operations and docking operations (commonly known as AR&D). The crewed missions may also perform rendezvous and docking operations and may require different levels of automation and/or autonomy, and must provide the crew with relative navigation information for manual piloting. The capabilities of the RPOD sensors are critical to the success ofthe Exploration Program. NASA has the responsibility to determine whether the Crew Exploration Vehicle (CEV) contractor-proposed relative navigation sensor suite will meet the requirements. The relatively low technology readiness level of AR&D relative navigation sensors has been carried as one of the CEV Project's top risks. The AR&D Sensor Technology Project seeks to reduce the risk by the testing and analysis of selected relative navigation sensor technologies through hardware-in-the-Ioop testing and simulation. These activities will provide the CEV Project information to assess the relative navigation sensors maturity as well as demonstrate test methods and capabilities. The first year of this project focused on a series of "pathfinder" testing tasks to develop the test plans, test facility requirements, trajectories, math model architecture, simulation platform, and processes that will be used to evaluate the Contractor-proposed sensors. Four candidate sensors were used in the first phase of the testing. The second phase of testing used four sensors simultaneously: two Marshall Space Flight Center (MSFC) Advanced Video Guidance Sensors (AVGS), a laser-based video sensor that uses retroreflectors attached to the target vehicle, and two commercial laser range finders. The multi-sensor testing was conducted at MSFC's Flight Robotics Laboratory (FRL

  11. Image Guidance

    Science.gov (United States)

    Guidance that explains the process for getting images approved in One EPA Web microsites and resource directories. includes an appendix that shows examples of what makes some images better than others, how some images convey meaning more than others

  12. 78 FR 68461 - Guidance for Industry: Studies To Evaluate the Utility of Anti-Salmonella Chemical Food Additives...

    Science.gov (United States)

    2013-11-14

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-1994-D-0007] Guidance for Industry: Studies To Evaluate the Utility of Anti- Salmonella Chemical Food Additives in Feeds... Industry: Studies to Evaluate the Utility of Anti-Salmonella Chemical Food Additives in Feeds,'' and is...

  13. Guidance on Conducting and REporting DElphi Studies (CREDES) in palliative care: Recommendations based on a methodological systematic review.

    Science.gov (United States)

    Jünger, Saskia; Payne, Sheila A; Brine, Jenny; Radbruch, Lukas; Brearley, Sarah G

    2017-09-01

    The Delphi technique is widely used for the development of guidance in palliative care, having impact on decisions with relevance for patient care. To systematically examine the application of the Delphi technique for the development of best practice guidelines in palliative care. A methodological systematic review was undertaken using the databases PubMed, CINAHL, Web of Science, Academic Search Complete and EMBASE. Original articles (English language) were included when reporting on empirical studies that had used the Delphi technique to develop guidance for good clinical practice in palliative care. Data extraction included a quality appraisal on the rigour in conduct of the studies and the quality of reporting. A total of 30 empirical studies (1997-2015) were considered for full-text analysis. Considerable differences were identified regarding the rigour of the design and the reporting of essential process and outcome parameters. Furthermore, discrepancies regarding the use of terms for describing the method were observed, for example, concerning the understanding of a 'round' or a 'modified Delphi study'. Substantial variation was found concerning the quality of the study conduct and the transparency of reporting of Delphi studies used for the development of best practice guidance in palliative care. Since credibility of the resulting recommendations depends on the rigorous use of the Delphi technique, there is a need for consistency and quality both in the conduct and reporting of studies. To allow a critical appraisal of the methodology and the resulting guidance, a reporting standard for Conducting and REporting of DElphi Studies (CREDES) is proposed.

  14. Nurses' provision of parental guidance regarding school-aged children's postoperative pain management: a descriptive correlational study.

    Science.gov (United States)

    He, Hong-Gu; Klainin-Yobas, Piyanee; Ang, Emily Neo Kim; Sinnappan, Rajammal; Pölkki, Tarja; Wang, Wenru

    2015-02-01

    Involving parents in children's pain management is essential to achieve optimal outcomes. Parents need to be equipped with sufficient knowledge and information. Only a limited number of studies have explored nurses' provision of parental guidance regarding the use of nonpharmacologic methods in children's pain management. This study aimed to examine nurses' perceptions of providing preparatory information and nonpharmacologic methods to parents, and how their demographics and perceived knowledge adequacy of these methods influence this guidance. A descriptive correlational study using questionnaire surveys was conducted to collect data from a convenience sample of 134 registered nurses working in seven pediatric wards of two public hospitals in Singapore. Descriptive statistics, independent-samples t test, and multiple linear regression were used to analyze the data. Most nurses provided various types of cognitive information to parents related to their children's surgery, whereas information about children's feelings was less often provided. Most nurses provided guidance to parents on positioning, breathing technique, comforting/reassurance, helping with activities of daily living, relaxation, and creating a comfortable environment. Nurses' provision of parental guidance on preparatory information and nonpharmacologic methods was significantly different between subgroups of age, education, parent or not, and perceived knowledge adequacy of nonpharmacologic methods. Nurses' perceived knowledge adequacy was the main factor influencing their provision of parental guidance. More attention should be paid to nurses who are younger, have less working experience, and are not parents. There is a need to educate nurses about nonpharmacologic pain relief methods to optimize their provision of parental guidance. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  15. Study of the Use of a Terminal Controller Technique for Reentry Guidance of a Capsule-Type Vehicle

    Science.gov (United States)

    Foudriat, Edwin C.

    1961-01-01

    A study has been made of the use o f a terminal controller technique i n the guidance of a high-drag, variable-lift reentry vehicle to a desired landing point. The technique uses linearized equations of motion attained by the perturbation of the dependent variables from those of a reference trajectory. The guidance system continuously predicts the terminal range error and uses this error to control the angle of attack of the vehicle in an on-off manner until the predicted range error is within +-O.1 degrees of the required arc or +-6.9 miles.

  16. Robust Tracking Control for Rendezvous in Near-Circular Orbits

    Directory of Open Access Journals (Sweden)

    Neng Wan

    2013-01-01

    Full Text Available This paper investigates a robust guaranteed cost tracking control problem for thrust-limited spacecraft rendezvous in near-circular orbits. Relative motion model is established based on the two-body problem with noncircularity of the target orbit described as a parameter uncertainty. A guaranteed cost tracking controller with input saturation is designed via a linear matrix inequality (LMI method, and sufficient conditions for the existence of the robust tracking controller are derived, which is more concise and less conservative compared with the previous works. Numerical examples are provided for both time-invariant and time-variant reference signals to illustrate the effectiveness of the proposed control scheme when applied to the terminal rendezvous and other astronautic missions with scheduled states signal.

  17. Comet rendezvous mission design using Solar Electric Propulsion

    Science.gov (United States)

    Sackett, L. L.; Hastrup, R. C.; Yen, C.-W. L.; Wood, L. J.

    1979-01-01

    A dual comet (Halley Flyby/Tempel 2 Rendezvous) mission, which is planned to be the first to use the Solar Electric Propulsion System (SEPS), is to be launched in 1985. The purpose of this paper is to describe how the mission design attempts to maximize science return while working within spacecraft and other constraints. Science requirements and desires are outlined and specific instruments are considered. Emphasis is on the strategy for operations in the vicinity of Tempel 2, for which a representative profile is described. The mission is planned to extend about one year past initial rendezvous. Because of the large uncertainty in the comet environment the Tempel 2 operations strategy must be highly adaptive.

  18. 78 FR 24425 - Assay Migration Studies for In Vitro Diagnostic Devices; Guidance for Industry and Food and Drug...

    Science.gov (United States)

    2013-04-25

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2008-D-0642] Assay Migration Studies for In Vitro Diagnostic Devices; Guidance for Industry and Food and Drug Administration Staff; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food...

  19. Verbal Self-Guidance as a Treatment Approach for Children with Developmental Coordination Disorder: A Systematic Replication Study.

    Science.gov (United States)

    Martini, Rose; Polatajko, Helene J.

    1998-01-01

    Replicating a 1994 study, four children with developmental coordination disorder (DCD) were taught a verbal self-guidance strategy (Goal, Plan, Do, Check) by an occupational therapist. All four improved performance in attaining their occupational goals, supporting the possible use of a cognitive strategy with children with DCD. (SK)

  20. Use of automated rendezvous trajectory planning to improve spacecraft operations efficiency

    Science.gov (United States)

    Mulder, Tom A.

    1991-01-01

    The current planning process for space shuttle rendezvous with a second Earth-orbiting vehicle is time consuming and costly. It is a labor-intensive, manual process performed pre-mission with the aid of specialized maneuver processing tools. Real-time execution of a rendezvous plan must closely follow a predicted trajectory, and targeted solutions leading up to the terminal phase are computed on the ground. Despite over 25 years of Gemini, Apollo, Skylab, and shuttle vehicle-to-vehicle rendezvous missions flown to date, rendezvous in Earth orbit still requires careful monitoring and cannot be taken for granted. For example, a significant trajectory offset was experienced during terminal phase rendezvous of the STS-32 Long Duration Exposure Facility retrieval mission. Several improvements can be introduced to the present rendezvous planning process to reduce costs, produce more fuel-efficient profiles, and increase the probability of mission success.

  1. Trajectory Control of Rendezvous with Maneuver Target Spacecraft

    Science.gov (United States)

    Zhou, Zhinqiang

    2012-01-01

    In this paper, a nonlinear trajectory control algorithm of rendezvous with maneuvering target spacecraft is presented. The disturbance forces on the chaser and target spacecraft and the thrust forces on the chaser spacecraft are considered in the analysis. The control algorithm developed in this paper uses the relative distance and relative velocity between the target and chaser spacecraft as the inputs. A general formula of reference relative trajectory of the chaser spacecraft to the target spacecraft is developed and applied to four different proximity maneuvers, which are in-track circling, cross-track circling, in-track spiral rendezvous and cross-track spiral rendezvous. The closed-loop differential equations of the proximity relative motion with the control algorithm are derived. It is proven in the paper that the tracking errors between the commanded relative trajectory and the actual relative trajectory are bounded within a constant region determined by the control gains. The prediction of the tracking errors is obtained. Design examples are provided to show the implementation of the control algorithm. The simulation results show that the actual relative trajectory tracks the commanded relative trajectory tightly. The predicted tracking errors match those calculated in the simulation results. The control algorithm developed in this paper can also be applied to interception of maneuver target spacecraft and relative trajectory control of spacecraft formation flying.

  2. Fatal central venous air embolism: a rare complication of esophageal dilation by rendezvous.

    Science.gov (United States)

    Zald, Philip B; Andersen, Peter E

    2011-03-01

    Esophageal dilation by rendezvous is a useful technique for the treatment of complicated esophageal strictures. We present a case of a 74-year-old man with chronic dysphagia caused by a complete cervical esophageal stricture that developed after external beam radiotherapy for treatment of papillary thyroid carcinoma. During attempted dilation using the rendezvous technique, the patient suffered a fatal pulmonary air embolism. The technique of esophageal dilation by rendezvous, complications, and risk factors for development of venous air embolism are discussed. To the best of our knowledge, this is the first report in the literature of fatal venous air embolism after dilation by rendezvous. Copyright © 2009 Wiley Periodicals, Inc.

  3. Combined Sector and Channel Hopping Schemes for Efficient Rendezvous in Directional Antenna Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    AbdulMajid M. Al-Mqdashi

    2017-01-01

    Full Text Available Rendezvous is a prerequisite and important process for secondary users (SUs to establish data communications in cognitive radio networks (CRNs. Recently, there has been a proliferation of different channel hopping- (CH- based schemes that can provide rendezvous without relying on any predetermined common control channel. However, the existing CH schemes were designed with omnidirectional antennas which can degrade their rendezvous performance when applied in CRNs that are highly crowded with primary users (PUs. In such networks, the large number of PUs may lead to the inexistence of any common available channel between neighboring SUs which result in a failure of their rendezvous process. In this paper, we consider the utilization of directional antennas in CRNs for tackling the issue. Firstly, we propose two coprimality-based sector hopping (SH schemes that can provide efficient pairwise sector rendezvous in directional antenna CRNs (DIR-CRNs. Then, we propose an efficient CH scheme that can be combined within the SH schemes for providing a simultaneous sector and channel rendezvous. The guaranteed rendezvous of our schemes are proven by deriving the theoretical upper bounds of their rendezvous delay metrics. Furthermore, extensive simulation comparisons with other related rendezvous schemes are conducted to illustrate the significant outperformance of our schemes.

  4. Short-range/Long-range Integrated Target (SLIT) for Video Guidance Sensor Rendezvous and Docking

    Science.gov (United States)

    Roe, Fred D. (Inventor); Bryan, Thomas C. (Inventor)

    2009-01-01

    A laser target reflector assembly for mounting upon spacecraft having a long-range reflector array formed from a plurality of unfiltered light reflectors embedded in an array pattern upon a hemispherical reflector disposed upon a mounting plate. The reflector assembly also includes a short-range reflector array positioned upon the mounting body proximate to the long-range reflector array. The short-range reflector array includes three filtered light reflectors positioned upon extensions from the mounting body. The three filtered light reflectors retro-reflect substantially all incident light rays that are transmissive by their monochromatic filters and received by the three filtered light reflectors. In one embodiment the short-range reflector array is embedded within the hemispherical reflector,

  5. Design, analysis and presentation of multinational economic studies: the need for guidance.

    Science.gov (United States)

    Pang, Francis

    2002-01-01

    Over the last decade, there has been a proliferation in the number of economic evaluations of pharmaceuticals to meet the growing demand for information about the economic benefits of healthcare technologies. The majority of these studies have been commissioned by pharmaceutical companies for the purposes of drawing attention to the resource and quality-of-life aspects of new or existing products. Such information has become important in overcoming a new obstacle, namely the demonstration of cost effectiveness (the so-called 'fourth hurdle'), in addition to the three well-established criteria of quality, tolerability and efficacy. To ensure the maintenance of standards, guidance for economic evaluations has emerged lately in the form of guidelines, regulations, principles, policies and positions. Drummond outlined three purposes of these guidelines, as follows: as a requirement prior to reimbursement, as statements of methodological standards, and as a statement of ethical standards. Such guidelines are designed to assist both the economic analyst and the decision-maker. In laying out the state of the art regarding the methodology of economic evaluation, guidelines assist the analyst in performing high-quality, scientifically valid studies, and assist the decision-maker in properly interpreting and assessing their quality. In response to these growing requirements for cost-effectiveness data globally, it has become increasingly common for economic evaluations to be conducted on an international scale. However, the recommendations in pharmacoeconomics guidelines regarding the manner in which these multinational economic evaluations should be designed, analysed and presented are too limited to be of any real value. This article examines the various issues that must be taken into consideration when conducting multinational studies, and provides a review of the techniques and approaches that have been suggested to date. It concludes with recommendations for potential

  6. COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.

    2009-01-01

    In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.

  7. Efficacy of the Laparoendoscopic "Rendezvous" to Treat Cholecystocholedocholithiasis in 210 Consecutive Patients: A Single Center Experience.

    Science.gov (United States)

    La Greca, Gaetano; Pesce, Antonio; Vitale, Marco; Mannino, Maurizio; Di Marco, Federica; Di Blasi, Michele; Lombardo, Rosario; Puleo, Stefano; Russello, Domenico; Latteri, Saverio

    2017-08-01

    The simultaneous laparoendoscopic "rendezvous" (LERV) represents an alternative to sequential or totally laparoscopic approaches for patients affected by cholecystocholedocholithiasis. The aim of this study was to analyze the results in a large series of 210 consecutive patients. From 2002 to 2016 all patients affected by cholecystocholedocholithiasis were treated with a standardized "tailored" LERV. The relevant technical features of the procedure were recorded. An analysis of feasibility, effectiveness in stone clearance, and safety was performed. Among 214 patients with common bile duct stones, 210 were treated with LERV and 4 with open rendezvous approach. Intraoperative cholangiography confirmed common bile duct stones in 179 patients (85.2%) or sludge in 18 (8.5%) and in 98.9% stone clearance was obtained endoscopically. Endoscopic papilla cannulation was feasible in 161 patients (76.7%), whereas in 49 (23.3%) a transcystic guidewire was needed. The overall LERV feasibility was 96.6%. The conversion rate to open surgery was 3.3%. Minor morbidity was observed in 1.9% of cases, mortality in 0.47%, and the mean hospital stay was 4.3 days. These results confirm the high effectiveness of LERV. This approach to treat cholecystocholedocholithiasis should be preferred and therefore implemented where a strong collaboration between surgeons and endoscopists is possible.

  8. The endoscopic ultrasonography-guided rendezvous technique for biliary cannulation: a technical review.

    Science.gov (United States)

    Isayama, Hiroyuki; Nakai, Yousuke; Kawakubo, Kazumichi; Kawakami, Hiroshi; Itoi, Takao; Yamamoto, Natsuyo; Kogure, Hirofumi; Koike, Kazuhiko

    2013-04-01

    Steady progress is being made in endoscopic biliary intervention, especially endoscopic ultrasonography (EUS)-guided procedures. The EUS-guided rendezvous technique (EUS-RV) is a salvage method for failed selective biliary cannulation. The overall success rate of EUS-RV in 247 cases from seven published articles was 74 % and the incidence of complications was 11 %. The main cause of failed rendezvous cannulation was difficulty passing a biliary stricture or papilla due to poor guidewire (GW) manipulation. A recent large study found a 98.3 % success rate and superiority to precutting. This report suggested using a hydrophilic guidewire. Major complications were bleeding (0.8 %), bile leakage (1.2 %), peritonitis (0.4 %), pneumoperitoneum (0.2 %), and pancreatitis (1.6 %). The approach routes for EUS-RV were transgastric, transduodenal short position, and transduodenal long position. The appropriate route for each patient should be used. GW selection for EUS-RV is critical, and a hydrophilic GW might be the most useful. The catheter can be inserted through the papilla alongside or over the wire. Alongside cannulation is convenient, but difficult. The problem with the over-the-wire technique is withdrawal of the GW in the accessory channel. EUS-RV is effective and safe, but is not established. The efficacy should be confirmed in a prospective comparative trial, and the necessary specialist equipment should be developed.

  9. Endo-laparoscopic rendezvous approach for pericardia with gastric posterior wall of gastrointestinal stromal tumor: analysis of 52 consecutive cases.

    Science.gov (United States)

    Ding, Po; Zhao, Yongjie

    2014-12-01

    Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the gastrointestinal tract and most frequently developed in the stomach, and surgical therapy is limited on removal of the tumor lesion. The aim of this study was to investigate the clinical values of endo-laparoscopic rendezvous approach for pericardial GISTs within gastric posterior wall. Surgical outcome and clinical data of 52 patients with pericardial GISTs within gastric posterior wall treated at Tianjin Peoples' Hospital from January 2004 to October 2013 were analyzed. Endo-laparoscopic rendezvous approach was used as an operative procedure for tumor resection ranged from 10 to 50 mm. Endoscopic ultrasound, computed tomography and microscopic findings all certified the gastric spindle type GIST locating in the submucosa to muscle proper. Endo-laparoscopic rendezvous approach was attempted in 52 patients (male/female: 31/21) with median age of 51 years (25-71 years). The median operating time was 80 min (range: 40-120 min) and median intra-operative blood loss was 26 ml (range: 10-50 ml). The median hospital stay was 5 days (range: 4-6 days), while the median tumor size was 25 mm (range: 7-50 mm). All operative margins were clear. There were no recurrences or metastases of all patients in a median follow-up of 24 months (range: 6-36 months). Endo-laparoscopic rendezvous approach is considered to represent the next revolution in surgery. The new technique is reliable and effective in clinical application, due to the advantages of accurate and quick localization for pericardial GIST within gastric posterior wall.

  10. Time and Covariance Threshold Triggered Optimal Uncooperative Rendezvous Using Angles-Only Navigation

    Directory of Open Access Journals (Sweden)

    Yue You

    2017-01-01

    Full Text Available A time and covariance threshold triggered optimal maneuver planning method is proposed for orbital rendezvous using angles-only navigation (AON. In the context of Yamanaka-Ankersen orbital relative motion equations, the square root unscented Kalman filter (SRUKF AON algorithm is developed to compute the relative state estimations from a low-volume/mass, power saving, and low-cost optical/infrared camera’s observations. Multi-impulsive Hill guidance law is employed in closed-loop linear covariance analysis model, based on which the quantitative relative position robustness and relative velocity robustness index are defined. By balancing fuel consumption, relative position robustness, and relative velocity robustness, we developed a time and covariance threshold triggered two-level optimal maneuver planning method, showing how these results correlate to past methods and missions and how they could potentially influence future ones. Numerical simulation proved that it is feasible to control the spacecraft with a two-line element- (TLE- level uncertain, 34.6% of range, initial relative state to a 100 m v-bar relative station keeping point, at where the trajectory dispersion reduces to 3.5% of range, under a 30% data gap per revolution on account of the eclipse. Comparing with the traditional time triggered maneuver planning method, the final relative position accuracy is improved by one order and the relative trajectory robustness and collision probability are obviously improved and reduced, respectively.

  11. Stricture location predicts swallowing outcomes following endoscopic rendezvous procedures.

    Science.gov (United States)

    Adams, Katherine N; Shah, Rupali N; Buckmire, Robert A

    2017-06-01

    Complete pharyngoesophageal strictures may be encountered by the otolaryngologist as a consequence of radiation/chemoradiotherapy therapies for head and neck cancer. A combined anterograde and retrograde dilation procedure (rendezvous procedure) has proven to be a useful surgical intervention in these cases. We assess the long-term swallowing outcomes of this patient cohort including gastrostomy tube (G-tube) reliance, swallowing quality of life, and variables that contribute to improved swallowing outcomes. Retrospective chart review. A retrospective chart review of 18 consecutive patients treated with rendezvous procedures between April 2007 and May 2015 was carried out. Data were collected from chart review and follow-up telephone calls including demographics, surgical/postoperative course details, and Eating Assessment Tool (EAT-10) (swallowing quality of life) scores. The completion rate of the procedure was 83% (15 completed/3 procedures aborted). Average follow-up was 22 months. Thirteen of 15 (86.7%) achieved an oral diet, and 7/15 (46.7%) had their G-tube removed. G-tube-independent (GTI) patients had an average stricture length of 2.33 cm and an average distance from the incisors of 17.4 cm compared to G-tube dependent-(GTD) patients who had an average stricture length of 2.63 cm and 14.6 cm mean distance from the incisors (P = .66 and .0343, respectively). Final EAT-10 scores averaged 20.1 in GTI patients and 33.8 in GTD patients (P = .022). Stricture/incisor distance and EAT-10 scores demonstrated a moderate to strong negative correlation (r = -0.67). Following the endoscopic rendezvous procedure, swallowing outcomes and G-tube status is related to the distance of the stricture from the incisors. 2b Laryngoscope, 127:1388-1391, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  12. PREDICTION BASED CHANNEL-HOPPING ALGORITHM FOR RENDEZVOUS IN COGNITIVE RADIO NETWORKS

    Directory of Open Access Journals (Sweden)

    Dhananjay Kumar

    2012-12-01

    Full Text Available Most common works for rendezvous in cognitive radio networks deal only with two user scenarios involving two secondary users and variable primary users and aim at reducing the time-to-rendezvous. A common control channel for the establishment of communication is not considered and hence the work comes under the category of ‘Blind Rendezvous’. Our work deal with multi-user scenario and provides a methodology for the users to find each other in the very first time slot spent for rendezvous or otherwise called the firstattempt- rendezvous. The secondary users make use of the history of past communications to enable them to predict the frequency channel that the user expects the rendezvous user to be. Our approach prevents greedy decision making between the users involved by the use of a cut-off time period for attempting rendezvous. Simulation results show that the time-to-rendezvous (TTR is greatly reduced upon comparison with other popular rendezvous algorithms.

  13. Virtual reality applications to automated rendezvous and capture

    Science.gov (United States)

    Hale, Joseph; Oneil, Daniel

    Virtual Reality (VR) is a rapidly developing Human/Computer Interface (HCI) technology. The evolution of high-speed graphics processors and development of specialized anthropomorphic user interface devices, that more fully involve the human senses, have enabled VR technology. Recently, the maturity of this technology has reached a level where it can be used as a tool in a variety of applications. This paper provides an overview of: VR technology, VR activities at Marshall Space Flight Center (MSFC), applications of VR to Automated Rendezvous and Capture (AR&C), and identifies areas of VR technology that requires further development.

  14. Towards a standardised approach for evaluating guidelines and guidance documents on palliative sedation: study protocol.

    Science.gov (United States)

    Abarshi, Ebun; Rietjens, Judith; Caraceni, Augusto; Payne, Sheila; Deliens, Luc; Van Den Block, Lieve

    2014-01-01

    Sedation in palliative care has received growing attention in recent years; and so have guidelines, position statements, and related literature that provide recommendations for its practice. Yet little is known collectively about the content, scope and methodological quality of these materials. According to research, there are large variations in palliative sedation practice, depending on the definition and methodology used. However, a standardised approach to comparing and contrasting related documents, across countries, associations and governmental bodies is lacking. This paper reports on a protocol designed to enable thorough and systematic comparison of guidelines and guidance documents on palliative sedation. A multidisciplinary and international group of palliative care researchers, identified themes and clinical issues on palliative sedation based on expert consultations and evidence drawn from the EAPC (European Association of Palliative Care) framework for palliative sedation and AGREE II (Appraisal Guideline Research and Evaluation) instrument for guideline assessment. The most relevant themes were selected and built into a comprehensive checklist. This was tested on people working closely with practitioners and patients, for user-friendliness and comprehensibility, and modified where necessary. Next, a systematic search was conducted for guidelines in English, Dutch, Flemish, or Italian. The search was performed in multiple databases (PubMed, CancerLit, CNAHL, Cochrane Library, NHS Evidence and Google Scholar), and via other Internet resources. Hereafter, the final version of the checklist will be used to extract data from selected literature, and the same will be compiled, entered into SPSS, cleaned and analysed systematically for publication. We have together developed a comprehensive checklist in a scientifically rigorous manner to allow standardised and systematic comparison. The protocol is applicable to all guidelines on palliative sedation, and

  15. International Conference on Harmonisation; Guidance on M3(R2) Nonclinical Safety Studies for the Conduct of Human Clinical Trials and Marketing Authorization for Pharmaceuticals; availability. Notice.

    Science.gov (United States)

    2010-01-21

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled "M3(R2) Nonclinical Safety Studies for the Conduct of Human Clinical Trials and Marketing Authorization for Pharmaceuticals.'' The guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The guidance, which is a revision of an existing guidance, discusses the types of nonclinical studies, their scope and duration, and their relation to the conduct of human clinical trials and marketing authorization for pharmaceuticals. The guidance is intended to facilitate the timely conduct of clinical trials and reduce the unnecessary use of animals and other drug development resources.

  16. A qualitative study in parental perceptions and understanding of SIDS-reduction guidance in a UK bi-cultural urban community.

    Science.gov (United States)

    Crane, Denise; Ball, Helen L

    2016-01-30

    Differences in both Sudden Infant Death Syndrome (SIDS) rates and infant care practices between white British and South Asians in UK are well known, but research has not yet examined how these two groups understand and implement SIDS-reduction guidance. This study aimed to discover how white British and Pakistani mothers in Bradford recall, understand and interpret SIDS-reduction guidance, and to explore whether and how they implement this guidance in caring for their infants. In-depth narrative interviews with 46 mothers (25 white British origin and 21 Pakistani origin) of 8-12 week old infants recruited from the pool of participants enrolled in the 'Born in Bradford' (BiB) cohort study. All mothers were aware of UK SIDS-reduction guidance from leaflets presented to them during antenatal or postnatal interactions with health care providers. Pakistani mothers tended to dismiss the guidance in toto as being irrelevant to their cultural practices; white British mothers dismissed, adapted and adopted aspects of the guidance to suit their preferred parenting decisions and personal circumstances. Many mothers misunderstood or misinterpreted the guidance given and explained their infant care behaviour according to their social and cultural circumstances. Current SIDS reduction information in the UK does not meet the needs of immigrant families, and is easily misinterpreted or misunderstood by mothers from all sections of the community. Tailored information acknowledging cultural differences in infant care practices is vital, as is greater discussion with all mothers about the reasons for SIDS reduction guidance.

  17. An automated rendezvous and capture system design concept for the cargo transfer vehicle and Space Station Freedom

    Science.gov (United States)

    Fuchs, Ron; Marsh, Steven

    1991-01-01

    A rendezvous sensor system concept was developed for the cargo transfer vehicle (CTV) to autonomously rendezvous with and be captured by Space Station Freedom (SSF). The development of requirements, the design of a unique Lockheed developed sensor concept to meet these requirements, and the system design to place this sensor on the CTV and rendezvous with the SSF are described .

  18. Modified rendezvous intrahepatic bile duct cannulation technique to pass a PTBD catheter in ERCP.

    Science.gov (United States)

    Lee, Tae Hoon; Park, Sang-Heum; Lee, Sae Hwan; Lee, Chang-Kyun; Lee, Suck-Ho; Chung, Il-Kwun; Kim, Hong Soo; Kim, Sun-Joo

    2010-11-14

    The rendezvous procedure combines an endoscopic technique with percutaneous transhepatic biliary drainage (PTBD). When a selective common bile duct cannulation fails, PTBD allows successful drainage and retrograde access for subsequent rendezvous techniques. Traditionally, rendezvous procedures such as the PTBD-assisted over-the-wire cannulation method, or the parallel cannulation technique, may be available when a bile duct cannot be selectively cannulated. When selective intrahepatic bile duct (IHD) cannulation fails, this modified rendezvous technique may be a feasible alternative. We report the case of a modified rendezvous technique, in which the guidewire was retrogradely passed into the IHD through the C2 catheter after end-to-end contact between the tips of the sphincterotome and the C2 catheter at the ampulla's orifice, in a 39-year-old man who had been diagnosed with gallbladder carcinoma with a metastatic right IHD obstruction. Clinically this procedure may be a feasible and timesaving technique.

  19. Bonneville Powerhouse 2 Fish Guidance Efficiency Studies: CFD Model of the Forebay

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.

    2012-07-01

    In ongoing work, U.S. Army Corps of Engineers, Portland District (CENWP) is seeking to better understand and improve the conditions within the Bonneville Powerhouse 2 (B2) turbine intakes to improve survival of downstream migrant salmonid smolt. In this study, the existing B2 forebay computational fluid dynamics (CFD) model was modified to include a more detailed representation of all B2 turbine intakes. The modified model was validated to existing field-measured forebay ADCP velocities. The initial CFD model scenarios tested a single project operation and the impact of adding the Behavior Guidance System (BGS) or Corner Collector. These structures had impacts on forebay flows. Most notable was that the addition of the BGS and Corner Collector reduced the lateral extent of the recirculation areas on the Washington shore and Cascade Island and reduced the flow velocity parallel to the powerhouse in front of Units 11 and 12. For these same cases, at the turbine intakes across the powerhouse, there was very little difference in the flow volume into the gatewell for the clean forebay, and the forebay with the BGS in place and/or the Corner Collector operating. The largest differences were at Units 11 to 13. The CFD model cases testing the impact of the gatewell slot fillers showed no impact to the forebay flows, but large differences within the gatewells. With the slot fillers, the flow above the standard traveling screen and into the gatewell increased (about 100 cfs at each turbine intake) and the gap flow decreased across the powerhouse for all cases. The increased flow up the gatewell was further enhanced with only half the units operating. The flow into the gatewell slot was increased about 35 cfs for each bay of each intake across the powerhouse; this change was uniform across the powerhouse. The flows in the gatewell of Unit 12, the most impacted unit for the scenarios, was evaluated. In front of the vertical barrier screen, the CFD model with slot fillers

  20. Management of low back pain with facet joint injections and nerve root blocks under computed tomography guidance. A prospective study

    International Nuclear Information System (INIS)

    Fotiadou, Anastasia; Wojcik, Andrew; Shaju, Antony

    2012-01-01

    The aim of this work was to assess the performance of facet joint and nerve root infiltrations under computed tomography guidance for the management of low back pain and to investigate the complications and patient tolerance. The study was board-certified and informed consent was obtained from all patients. In 1 year, 86 consecutive patients (47 male, 39 female, age range 47-87 years, mean age 63) with low back pain for more than 2 years were included. All patients were clinically examined and had cross-sectional imaging performed before the procedure. Fifty-five facet joint infiltrations and 31 nerve blocks were performed under computed tomography guidance. All patients completed two valid pain questionnaires before and 3 months after the procedures. At the same time, they were clinically examined by the referring Orthopaedic Surgeon. The pain response was assessed by comparing the scores of the questionnaires. The improvement in clinical examination findings was assessed as well. In patients who underwent facet joint infiltrations, long-term pain improvement was achieved in 79% and in those with nerve blocks in 85%. Immediate pain relief was demonstrated in 83% of patients with nerve infiltrations. No complications were observed. All procedures were very well tolerated by patients. Facet joint and nerve infiltrations under computed tomography guidance constitute an accurate and safe method that could be used to relieve low back pain and minimize the risk of disability. (orig.)

  1. Operator learning effects in teleoperated rendezvous & docking

    Science.gov (United States)

    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.

  2. Au rendez-vous allemand (2

    Directory of Open Access Journals (Sweden)

    Agnès Bouvier

    2010-12-01

    Full Text Available La parution en 1857 des Études d’histoire religieuse d’Ernest Renan marque l’entrée en France des conceptions allemandes du mythe appliquées à l’histoire des textes sacrés. Or, cette date est aussi celle de la rencontre intellectuelle entre Renan et Flaubert, rencontre qui se matérialisera deux ans plus tard : au moment où Flaubert entreprend Salammbô, il accède aux travaux philologiques de la « nouvelle école » représentée en France par Renan. La supériorité de l’école allemande tient essentiellement selon Renan à sa capacité de penser le mythe comme un tout « indivis » irréductible à toute interprétation univoque : en dépit de certaines outrances des « rationalistes » et des « mythologues », dont il distingue nettement les deux types d’approche, Renan envisage l’exégèse allemande comme un progrès dont il montre les étapes et qu’il se propose d’achever en développant ce qu’il appelle une critique « sympathique ». Davantage qu’une méthode, il définit une posture critique d’adhésion à l’objet que Flaubert pourra mettre en oeuvre dans son roman.The publication in 1857 of Ernest Renan’s Études d’histoire religieuse signals the introduction in France of German ideas about myths applied to the history of religious texts. Now this date is also that of the intellectual encounter between Renan and Flaubert. Their actual meeting came about two years later. Indeed, while Flaubert was starting Salammbô, he discovered the philological studies of the “New School” represented in France by Renan. According to Renan the superiority of the German School was due to its capacity to comprehend the myth as an undivided whole irreducible to a univocal interpretation. Thus, despite the excesses of the “rationalists” and “mythologs”, whose methods he clearly distinguished, Renan considered the German exegesis a progress. He outlined its stages which he sought to complete by

  3. Low-Income Women's Feeding Practices and Perceptions of Dietary Guidance: A Qualitative Study.

    Science.gov (United States)

    Savage, Jennifer S; Neshteruk, Cody D; Balantekin, Katherine N; Birch, Leann L

    2016-12-01

    Objectives Describe themes characterizing feeding behaviors of low-income women participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), and identify the attitudes, beliefs, and sources of information that inform these practices. Methods Formative research was conducted including focus groups and semi-structured individual phone interviews with a total of 68 low-income women participating in WIC. Qualitative data were recorded, transcribed, imported into NVivo 8.0, and analyzed for common themes. Results Mothers reported feeding behaviors inconsistent with guidance from WIC and the American Academy of Pediatrics. Three main themes were identified. First, mothers reported receiving conflicting messaging/advice from medical professionals, WIC nutritionists, and family members, which was confusing. Mothers also reported dissatisfaction with the "one size fits most" approach. Lastly, mothers reported relying on their "instincts" and that "all babies are different" when deciding and rationalizing what feeding guidance to follow. Conclusions Future interventions targeting this high-risk population should consider developing personalized (individualized) messaging, tailored to the needs of each mother-child dyad. Focused efforts are needed to build partnerships between WIC providers and other health care providers to provide more consistent messages about responsive feeding to prevent early obesity.

  4. The discovery of the growth cone and its influence on the study of axon guidance

    Directory of Open Access Journals (Sweden)

    Elisa eTamariz

    2015-05-01

    Full Text Available For over a century, there has been a great deal of interest in understanding how neural connectivity is established during development and regeneration. Interest in the latter arises from the possibility that knowledge of this process can be used to reestablish lost connections after lesion or neurodegeneration. At the end of the XIX century, Santiago Ramón y Cajal discovered that the distal tip of growing axons contained a structure that he called the growth cone. He proposed that this structure enabled the axon’s oriented growth in response to attractants, now known as chemotropic molecules. He further proposed that the physical properties of the surrounding tissues could influence the growth cone and the direction of growth. This seminal discovery afforded a plausible explanation for directed axonal growth and has led to the discovery of axon guidance mechanisms that include diffusible attractants and repellants and guidance cues anchored to cell membranes or extracellular matrix. In this review the major events in the development of this field are discussed.

  5. Non-cable vehicle guidance

    Energy Technology Data Exchange (ETDEWEB)

    Daugela, G.C.; Willott, A.M.; Chopiuk, R.G.; Thornton, S.E.

    1988-06-01

    The purpose is to determine the most promising driverless mine vehicle guidance systems that are not dependent on buried cables, and to plan their development. The project is presented in two phases: a preliminary study and literature review to determine whether suitable technologies exist to justify further work; and an in-depth assessment and selection of technologies for vehicle guidance. A large number of guidance elements are involved in a completely automated vehicle. The technologies that hold the best potential for development of guidance systems for mine vehicles are ultrasonics, radar, lasers, dead reckoning, and guidance algorithms. The best approach to adaptation of these technologies is on a step by step basis. Guidance modules that are complete in themselves and are designed to be integrated with other modules can provide short term benefits. Two modules are selected for development: the dragline operations monitor and automated machine control for optimized mining (AMCOM). 99 refs., 20 figs., 40 tabs.

  6. The Evolution of the Rendezvous Profile During the Space Shuttle Program

    Science.gov (United States)

    Summa, William R.

    2010-01-01

    The rendezvous and proximity operations approach design techniques for space shuttle missions has changed significantly during the life of the program in response to new requirements that were not part of the original mission design. The flexibility of the shuttle onboard systems design and the mission planning process has allowed the program to meet these requirements. The design of the space shuttle and the shift from docking to grappling with a robotic ann prevented use of legacy Apollo rendezvous techniques. Over the life of the shuttle program the rendezvous profile has evolved due to several factors, including lowering propellant consumption and increasing flexibility in mission planning. Many of the spacecraft that the shuttle rendezvoused with had unique requirements that drove the creation of mission-unique proximity operations. The dockings to the Russian Mir space station and International Space Station (ISS) required further evolution of rendezvous and proximity operations techniques and additional sensors to enhance crew situational awareness. After the Columbia accident, a Rendezvous Pitch Maneuver (RPM) was added to allow tile photography from ISS. Lessons learned from these rendezvous design changes are applicable to future vehicle designs and operations concepts.

  7. Gossip-based solutions for discrete rendezvous in populations of communicating agents.

    Science.gov (United States)

    Hollander, Christopher D; Wu, Annie S

    2014-01-01

    The objective of the rendezvous problem is to construct a method that enables a population of agents to agree on a spatial (and possibly temporal) meeting location. We introduce the buffered gossip algorithm as a general solution to the rendezvous problem in a discrete domain with direct communication between decentralized agents. We compare the performance of the buffered gossip algorithm against the well known uniform gossip algorithm. We believe that a buffered solution is preferable to an unbuffered solution, such as the uniform gossip algorithm, because the use of a buffer allows an agent to use multiple information sources when determining its desired rendezvous point, and that access to multiple information sources may improve agent decision making by reinforcing or contradicting an initial choice. To show that the buffered gossip algorithm is an actual solution for the rendezvous problem, we construct a theoretical proof of convergence and derive the conditions under which the buffered gossip algorithm is guaranteed to produce a consensus on rendezvous location. We use these results to verify that the uniform gossip algorithm also solves the rendezvous problem. We then use a multi-agent simulation to conduct a series of simulation experiments to compare the performance between the buffered and uniform gossip algorithms. Our results suggest that the buffered gossip algorithm can solve the rendezvous problem faster than the uniform gossip algorithm; however, the relative performance between these two solutions depends on the specific constraints of the problem and the parameters of the buffered gossip algorithm.

  8. Gossip-based solutions for discrete rendezvous in populations of communicating agents.

    Directory of Open Access Journals (Sweden)

    Christopher D Hollander

    Full Text Available The objective of the rendezvous problem is to construct a method that enables a population of agents to agree on a spatial (and possibly temporal meeting location. We introduce the buffered gossip algorithm as a general solution to the rendezvous problem in a discrete domain with direct communication between decentralized agents. We compare the performance of the buffered gossip algorithm against the well known uniform gossip algorithm. We believe that a buffered solution is preferable to an unbuffered solution, such as the uniform gossip algorithm, because the use of a buffer allows an agent to use multiple information sources when determining its desired rendezvous point, and that access to multiple information sources may improve agent decision making by reinforcing or contradicting an initial choice. To show that the buffered gossip algorithm is an actual solution for the rendezvous problem, we construct a theoretical proof of convergence and derive the conditions under which the buffered gossip algorithm is guaranteed to produce a consensus on rendezvous location. We use these results to verify that the uniform gossip algorithm also solves the rendezvous problem. We then use a multi-agent simulation to conduct a series of simulation experiments to compare the performance between the buffered and uniform gossip algorithms. Our results suggest that the buffered gossip algorithm can solve the rendezvous problem faster than the uniform gossip algorithm; however, the relative performance between these two solutions depends on the specific constraints of the problem and the parameters of the buffered gossip algorithm.

  9. Orion Handling Qualities During ISS Rendezvous and Docking

    Science.gov (United States)

    Hart, Jeremy J.; Stephens, J. P.; Spehar, P.; Bilimoria, K.; Foster, C.; Gonzalex, R.; Sullivan, K.; Jackson, B.; Brazzel, J.; Hart, J.

    2011-01-01

    The Orion spacecraft was designed to rendezvous with multiple vehicles in low earth orbit (LEO) and beyond. To perform the required rendezvous and docking task, Orion must provide enough control authority to perform coarse translational maneuvers while maintaining precision to perform the delicate docking corrections. While Orion has autonomous docking capabilities, it is expected that final approach and docking operations with the International Space Station (ISS) will initially be performed in a manual mode. A series of evaluations was conducted by NASA and Lockheed Martin at the Johnson Space Center to determine the handling qualities (HQ) of the Orion spacecraft during different docking and rendezvous conditions using the Cooper-Harper scale. This paper will address the specifics of the handling qualities methodology, vehicle configuration, scenarios flown, data collection tools, and subject ratings and comments. The initial Orion HQ assessment examined Orion docking to the ISS. This scenario demonstrates the Translational Hand Controller (THC) handling qualities of Orion. During this initial assessment, two different scenarios were evaluated. The first was a nominal docking approach to a stable ISS, with Orion initializing with relative position dispersions and a closing rate of approximately 0.1 ft/sec. The second docking scenario was identical to the first, except the attitude motion of the ISS was modeled to simulate a stress case ( 1 degree deadband per axis and 0.01 deg/sec rate deadband per axis). For both scenarios, subjects started each run on final approach at a docking port-to-port range of 20 ft. Subjects used the THC in pulse mode with cues from the docking camera image, window views, and range and range rate data displayed on the Orion display units. As in the actual design, the attitude of the Orion vehicle was held by the automated flight control system at 0.5 degree deadband per axis. Several error sources were modeled including Reaction

  10. A clinico-radiographic study to compare and co-relate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in completely edentulous patients

    Directory of Open Access Journals (Sweden)

    Sanath Shetty

    2018-01-01

    Conclusion: Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used for programming semi-adjustable articulators.

  11. Satellite Servicing's Autonomous Rendezvous and Docking Testbed on the International Space Station

    Science.gov (United States)

    Naasz, Bo J.; Strube, Matthew; Van Eepoel, John; Barbee, Brent W.; Getzandanner, Kenneth M.

    2011-01-01

    The Space Servicing Capabilities Project (SSCP) at NASA's Goddard Space Flight Center (GSFC) has been tasked with developing systems for servicing space assets. Starting in 2009, the SSCP completed a study documenting potential customers and the business case for servicing, as well as defining several notional missions and required technologies. In 2010, SSCP moved to the implementation stage by completing several ground demonstrations and commencing development of two International Space Station (ISS) payloads-the Robotic Refueling Mission (RRM) and the Dextre Pointing Package (DPP)--to mitigate new technology risks for a robotic mission to service existing assets in geosynchronous orbit. This paper introduces the DPP, scheduled to fly in July of 2012 on the third operational SpaceX Dragon mission, and its Autonomous Rendezvous and Docking (AR&D) instruments. The combination of sensors and advanced avionics provide valuable on-orbit demonstrations of essential technologies for servicing existing vehicles, both cooperative and non-cooperative.

  12. Rendezvous with connectivity preservation for multi-robot systems with an unknown leader

    Science.gov (United States)

    Dong, Yi

    2018-02-01

    This paper studies the leader-following rendezvous problem with connectivity preservation for multi-agent systems composed of uncertain multi-robot systems subject to external disturbances and an unknown leader, both of which are generated by a so-called exosystem with parametric uncertainty. By combining internal model design, potential function technique and adaptive control, two distributed control strategies are proposed to maintain the connectivity of the communication network, to achieve the asymptotic tracking of all the followers to the output of the unknown leader system, as well as to reject unknown external disturbances. It is also worth to mention that the uncertain parameters in the multi-robot systems and exosystem are further allowed to belong to unknown and unbounded sets when applying the second fully distributed control law containing a dynamic gain inspired by high-gain adaptive control or self-tuning regulator.

  13. Percutaneous rendezvous technique for the management of a bile duct injury.

    Science.gov (United States)

    Meek, James; Fletcher, Savannah; Crumley, Kristen; Culp, W C; Meek, Mary

    2018-02-01

    The rendezvous technique typically involves combined efforts of interventional radiology, endoscopy, and surgery. It can be done solely percutaneously, whereby the interventionalist gains desired access to one point in the body by approaching it from two different access sites. We present the case of a woman who underwent cholecystectomy complicated by a bile duct injury. A percutaneous rendezvous procedure enabled placement of an internal-external drain from the intrahepatic ducts through the biloma and distal common bile duct and into the duodenum. Thus, a percutaneous rendezvous technique is feasible for managing a bile duct injury when endoscopic retrograde cholangio-pancreatography or percutaneous transhepatic cholangiogram alone has been unsuccessful.

  14. Totally percutaneous rendezvous techniques for the treatment of bile strictures and leakages.

    Science.gov (United States)

    De Robertis, Riccardo; Contro, Alberto; Zamboni, Giulia; Mansueto, Giancarlo

    2014-04-01

    Some challenging pathologic conditions of the biliary tract cannot be treated with endoscopy alone, and a combined approach with rendezvous techniques is frequently needed. Three different totally percutaneous rendezvous techniques were successfully applied in three cases. The rendezvous techniques were performed either with bilateral catheterization of bile ducts to treat a challenging type IV biliary stenosis and iatrogenic biliary damage or with biliary catheterization and percutaneous puncture of the anastomotic loop to treat a biliodigestive anastomosis failure with bile leakage. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  15. Percutaneous rendezvous technique for the management of a bile duct injury

    Directory of Open Access Journals (Sweden)

    James Meek, DO

    2018-02-01

    Full Text Available The rendezvous technique typically involves combined efforts of interventional radiology, endoscopy, and surgery. It can be done solely percutaneously, whereby the interventionalist gains desired access to one point in the body by approaching it from two different access sites. We present the case of a woman who underwent cholecystectomy complicated by a bile duct injury. A percutaneous rendezvous procedure enabled placement of an internal-external drain from the intrahepatic ducts through the biloma and distal common bile duct and into the duodenum. Thus, a percutaneous rendezvous technique is feasible for managing a bile duct injury when endoscopic retrograde cholangio-pancreatography or percutaneous transhepatic cholangiogram alone has been unsuccessful.

  16. A Comparison Between Orion Automated and Space Shuttle Rendezvous Techniques

    Science.gov (United States)

    Ruiz, Jose O,; Hart, Jeremy

    2010-01-01

    The Orion spacecraft will replace the space shuttle and will be the first human spacecraft since the Apollo program to leave low earth orbit. This vehicle will serve as the cornerstone of a complete space transportation system with a myriad of mission requirements necessitating rendezvous to multiple vehicles in earth orbit, around the moon and eventually beyond . These goals will require a complex and robust vehicle that is, significantly different from both the space shuttle and the command module of the Apollo program. Historically, orbit operations have been accomplished with heavy reliance on ground support and manual crew reconfiguration and monitoring. One major difference with Orion is that automation will be incorporated as a key element of the man-vehicle system. The automated system will consist of software devoted to transitioning between events based on a master timeline. This effectively adds a layer of high level sequencing that moves control of the vehicle from one phase to the next. This type of automated control is not entirely new to spacecraft since the shuttle uses a version of this during ascent and entry operations. During shuttle orbit operations however many of the software modes and hardware switches must be manually configured through the use of printed procedures and instructions voiced from the ground. The goal of the automation scheme on Orion is to extend high level automation to all flight phases. The move towards automation represents a large shift from current space shuttle operations, and so these new systems will be adopted gradually via various safeguards. These include features such as authority-to-proceed, manual down modes, and functional inhibits. This paper describes the contrast between the manual and ground approach of the space shuttle and the proposed automation of the Orion vehicle. I will introduce typical orbit operations that are common to all rendezvous missions and go on to describe the current Orion automation

  17. Robust control for constant thrust rendezvous under thrust failure

    Directory of Open Access Journals (Sweden)

    Qi Yongqiang

    2015-04-01

    Full Text Available A robust constant thrust rendezvous approach under thrust failure is proposed based on the relative motion dynamic model. Firstly, the design problem is cast into a convex optimization problem by introducing a Lyapunov function subject to linear matrix inequalities. Secondly, the robust controllers satisfying the requirements can be designed by solving this optimization problem. Then, a new algorithm of constant thrust fitting is proposed through the impulse compensation and the fuel consumption under the theoretical continuous thrust and the actual constant thrust is calculated and compared by using the method proposed in this paper. Finally, the proposed method having the advantage of saving fuel is proved and the actual constant thrust switch control laws are obtained through the isochronous interpolation method, meanwhile, an illustrative example is provided to show the effectiveness of the proposed control design method.

  18. Deep Interior: Multiple-Rendezvous Prospecting of NEOs

    Science.gov (United States)

    Kakuda, R. Y.; Asphaug, E.; Belton, M. J. S.; Gulkis, S.; Huebner, W. F.

    2000-10-01

    This is an international multiple-rendezvous mission designed to prospect the deep interior and subsurface geophysical properties of diverse near-Earth objects, using reflection radar tomography, imaging, gravity, and explosions. What we learn will greatly influence future missions and guide strategies for the diversion, disruption, or utilization of potentially hazardous objects. Deep Interior. Low-frequency radar to determine internal variations of complex permittivity at resolutions approaching 20 m. Map inclusions or voids, fracture geometries, and compositional or structural boundaries. Subsurface. High-frequency radar to determine depth of regolith, existence and nature of cometary mantle, geology beneath and around craters, and subsurface expressions to surface geology. Topography and Geodesy. Stereogrammetric imaging with 1 m/pixel spatial resolution, supplemented by radar altimetry in shadowed regions, to determine detailed shape, volume, and spin state. Compare with radar sounding to learn how internal structure is manifested on the surface. Mass and Density. Total mass and lower moments of the internal mass distribution by mapping the exterior gravitational field. Look for mass concentrations. Surface microphysics and composition. Map color, albedo, and scattering properties of the surface over sunlit regions in six optical filters. Material properties. Deploy grenades to characterize the mechanics and dynamics of surface materials. Record 8 frame/sec, 20 cm/pixel videos of crater formation and ejecta dynamics, to enable simple and direct laboratory constraints on material density, cohesion and porosity. Dust. Look for dust lofted by surface waves propagating from the explosions, to constrain elastic properties and attenuation. Observe longer-term dynamics and optical properties of dust "atmosphere" generated by human activity. Cometary Activity. At comet 107P/Wilson-Harrington, look for expressions of past cometary activity, and for possible awakening

  19. Framework for Small-Scale Experiments in Software Engineering: Guidance and Control Software Project: Software Engineering Case Study

    Science.gov (United States)

    Hayhurst, Kelly J.

    1998-01-01

    Software is becoming increasingly significant in today's critical avionics systems. To achieve safe, reliable software, government regulatory agencies such as the Federal Aviation Administration (FAA) and the Department of Defense mandate the use of certain software development methods. However, little scientific evidence exists to show a correlation between software development methods and product quality. Given this lack of evidence, a series of experiments has been conducted to understand why and how software fails. The Guidance and Control Software (GCS) project is the latest in this series. The GCS project is a case study of the Requirements and Technical Concepts for Aviation RTCA/DO-178B guidelines, Software Considerations in Airborne Systems and Equipment Certification. All civil transport airframe and equipment vendors are expected to comply with these guidelines in building systems to be certified by the FAA for use in commercial aircraft. For the case study, two implementations of a guidance and control application were developed to comply with the DO-178B guidelines for Level A (critical) software. The development included the requirements, design, coding, verification, configuration management, and quality assurance processes. This paper discusses the details of the GCS project and presents the results of the case study.

  20. A clinico-radiographic study to compare and co-relate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in completely edentulous patients.

    Science.gov (United States)

    Shetty, Sanath; Kunta, Mythili; Shenoy, Kamalakanth

    2018-01-01

    The purpose of this study was to compare and correlate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in edentulous patients. Twelve completely edentulous patients were selected by the inclusion and exclusion criteria. Conventional steps in the fabrication of complete denture till jaw relation were carried out. Intraoral gothic arch tracing and protrusive interocclusal records were obtained for each patient. Protrusive interocclusal record was used to program the Hanau Wide-Vue semi-adjustable articulator, thus obtaining the sagittal condylar guidance angle. Using RadiAnt DICOM software, on the orthopantomogram obtained for each patient in the study, two reference lines were drawn. The Frankfort's horizontal plane and the mean curvature line (joining the most superior and the inferior points on the glenoid fossa curvature) were drawn. The mean curvature line was extended to intersect the Frankfort's horizontal plane, thus obtaining the radiographic sagittal condylar guidance angle. The condylar guidance angles obtained by these two methods were compared and subjected to paired t -test. There was no statistically significant difference between the sagittal condylar guidance angles obtained between right and left sides with intraoral gothic arch tracing and radiographic methods ( P = 0.107 and 0.07, respectively). Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used for programming semi-adjustable articulators.

  1. An Application of Linear Covariance Analysis to the Design of Responsive Near-Rendezvous Missions

    National Research Council Canada - National Science Library

    Visser, Benjamin L

    2007-01-01

    This thesis investigates a new class of launch vehicles capable of being released from an aircraft which ultimately have the goal of achieving near-rendezvous conditions at orbital altitudes up to 800 km...

  2. AggieSat: Autonomous Rendezvous and Docking Technology Demonstrator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Current autonomous rendezvous and docking (AR&D) capability in low Earth orbit (LEO) is constrained by sensor and effector mass, power, and accuracy limits. To...

  3. Clinical utility of an endoscopic ultrasound-guided rendezvous technique via various approach routes.

    Science.gov (United States)

    Kawakubo, Kazumichi; Isayama, Hiroyuki; Sasahira, Naoki; Nakai, Yousuke; Kogure, Hirofumi; Hamada, Tsuyoshi; Miyabayashi, Koji; Mizuno, Suguru; Sasaki, Takashi; Ito, Yukiko; Yamamoto, Natsuyo; Hirano, Kenji; Tada, Minoru; Koike, Kazuhiko

    2013-09-01

    The endoscopic ultrasound-guided rendezvous techniques (EUS-rendezvous) provide reliable biliary access after failed endoscopic retrograde cholangiopancreatography (ERCP) cannulation. We evaluated the clinical utility of an EUS-rendezvous technique using various approach routes. Patients undergoing EUS-rendezvous for biliary access after failed bile duct cannulation in ERCP were included. EUS-rendezvous was performed via three approach routes depending on the patient's condition: transgastric, transduodenal in a short endoscopic position, or transduodenal in a long endoscopic position. The main outcomes were the technical success rates. Secondary outcomes were procedure time and complications. Fourteen patients (median age, 77 years) underwent EUS-rendezvous for biliary access resulting from failed biliary cannulation. The reasons for biliary drainage were malignant biliary obstruction in five patients and choledocholithiasis in nine. Transgastric, transduodenal in a short position, and transduodenal in a long position EUS-rendezvous was performed in five, five, and four patients, respectively. Bile duct puncture occurred in the left intrahepatic duct in four patients, right hepatic duct in one, middle common bile duct in four, and lower common bile duct in five. The technical success rate was 100 %. In four patients, the approach route was modified from transduodenal in a short position to transduodenal in a long position or transgastric route. The median procedure time was 81 min. One case each of biliary peritonitis and pancreatitis occurred and were managed conservatively. EUS-rendezvous provided safe and reliable transpapillary bile duct access after failed ERCP cannulation. The selection of the appropriate approach routes, depending on patient condition, is critical.

  4. Intra-urinoma Rendezvous Using a Transconduit Approach to Re-establish Ureteric Integrity

    International Nuclear Information System (INIS)

    Anderson, Hugh; Alyas, Faisal; Edwin, Patrick Joseph

    2005-01-01

    Ureteric discontinuity following injury has been traditionally treated surgically. With the advent of improved interventional instrumentation it is possible to stent these lesions percutaneously, retrogradely or failing that using a combined (rendezvous) technique. We describe an intra-urinoma rendezvous procedure combining a percutaneous antegrade-transconduit retrograde technique of stent insertion to successfully re-establish ureteric integrity that was used following the failure of a percutaneous retrograde approach. We illustrate its usefulness as an alternative to surgery

  5. Cooperative Rendezvous and Docking for Underwater Robots Using Model Predictive Control and Dual Decomposition

    DEFF Research Database (Denmark)

    Nielsen, Mikkel Cornelius; Johansen, Tor Arne; Blanke, Mogens

    2018-01-01

    This paper considers the problem of rendezvous and docking with visual constraints in the context of underwater robots with camera-based navigation. The objective is the convergence of the vehicles to a common point while maintaining visual contact. The proposed solution includes the design of a ...... of a distributed model predictive controller based on dual decomposition, which allows for optimization in a decentralized fashion. The proposed distributed controller enables rendezvous and docking between vehicles while maintaining visual contact....

  6. Levodopa increases oxidative stress and repulsive guidance molecule A levels: a pilot study in patients with Parkinson's disease.

    Science.gov (United States)

    Müller, Thomas; Trommer, Isabel; Muhlack, Siegfried; Mueller, Bernhard K

    2016-04-01

    Exposure to free radicals influences synthesis, degradation and function of proteins, such as repulsive guidance molecule A. Decay of this protein is essential for neuronal maintenance and recovery. Levodopa elevates oxidative stress. Therefore levodopa may impact repulsive guidance molecule A metabolism. Objectives were to investigate plasma concentrations of repulsive guidance molecule A, levodopa, cysteine and cysteinyl-glycine before and 1 h after levodopa application in patients with Parkinson's disease. Cysteine and cysteinyl-glycine as biomarkers for oxidative stress exposure decreased, repulsive guidance molecule A and levodopa rose. Repulsive guidance molecule A remained unchanged in levodopa naïve patients, but particularly went up in patients on a prior chronic levodopa regimen. Decay of cysteine specifically cysteinyl-glycine results from an elevated glutathione generation with rising cysteine consumption respectively from the alternative glutathione transformation to its oxidized form glutathione disulfide after free radical scavenging. Repulsive guidance molecule A rise may inhibit physiologic mechanisms for neuronal survival.

  7. Percutaneous discectomy on lumbar radiculopathy related to disk herniation: Why under CT guidance? An open study of 100 consecutive patients

    International Nuclear Information System (INIS)

    Amoretti, Nicolas; Hauger, Olivier; Marcy, Pierre-Yves; Amoretti, Marie-eve; Lesbats, Virginie; Yvonne, Maratos; Ianessi, Antoine; Boileau, Pascal

    2012-01-01

    The primary objective of this study conducted on 100 patients is to demonstrate that performing CT-guided percutaneous discectomy for herniated disks results in a significant improvement in pain symptoms at several times (D1, D2, D7, 1 month, 3 months, 6 months). This objective assesses the effectiveness and feasibility of this technique under CT guidance in patients presenting documented lower back pain related to disk herniation that has not improved with appropriate medical treatment. The impact of various factors on the effectiveness of discectomy will also be evaluated. At 1 week, we notes a decrease in average VAS respectively of 71% and 67% in patients treated for posterolateral and foraminal herniated disks; the result for posteromedian herniated disks is only 45% in average decrease. At 6 months post op, 79% of lateralized herniated disks have a satisfactory result (≥70% decrease in pain as compared to initial pain), whereas post median herniated disks had a satisfactory result in only 50% of cases. Percutaneous fine needle discectomy probe under combined CT and fluoroscopic guidance is a minimally invasive spine surgery which should be considered as an alternative to surgery. This technique presents several advantages: the small diameter of the probe used (maximum 16G or 1.5 mm) allows a cutaneous incision of only a few millimeters, and a trans-canal approach can be possible; it also decreases the risk of ligamentary lesion and does not cause an osseous lesion of the posterior arc or of the adjacent muscular structures.

  8. Feasibility Study of Needle Placement in Percutaneous Vertebroplasty: Cone-Beam Computed Tomography Guidance Versus Conventional Fluoroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Braak, Sicco J., E-mail: sjbraak@gmail.com [St. Antonius Hospital, Department of Radiology (Netherlands); Zuurmond, Kirsten, E-mail: kirsten.zuurmond@philips.com; Aerts, Hans C. J., E-mail: hans.cj.aerts@philips.com [Philips Medical, Department of Clinical Development (Netherlands); Leersum, Marc van, E-mail: m.van.leersum@antoniusziekenhuis.nl; Overtoom, Timotheus T. Th., E-mail: overtm@knoware.nl; Heesewijk, Johannes P. M. van, E-mail: j.heesewijk@antoniusziekenhuis.nl; Strijen, Marco J. L. van, E-mail: m.van.strijen@antoniusziekenhuis.nl [St. Antonius Hospital, Department of Radiology (Netherlands)

    2013-08-01

    ObjectiveTo investigate the accuracy, procedure time, fluoroscopy time, and dose area product (DAP) of needle placement during percutaneous vertebroplasty (PVP) using cone-beam computed tomography (CBCT) guidance versus fluoroscopy.Materials and MethodsOn 4 spine phantoms with 11 vertebrae (Th7-L5), 4 interventional radiologists (2 experienced with CBCT guidance and two inexperienced) punctured all vertebrae in a bipedicular fashion. Each side was randomization to either CBCT guidance or fluoroscopy. CBCT guidance is a sophisticated needle guidance technique using CBCT, navigation software, and real-time fluoroscopy. The placement of the needle had to be to a specific target point. After the procedure, CBCT was performed to determine the accuracy, procedure time, fluoroscopy time, and DAP. Analysis of the difference between methods and experience level was performed.ResultsMean accuracy using CBCT guidance (2.61 mm) was significantly better compared with fluoroscopy (5.86 mm) (p < 0.0001). Procedure time was in favor of fluoroscopy (7.39 vs. 10.13 min; p = 0.001). Fluoroscopy time during CBCT guidance was lower, but this difference is not significant (71.3 vs. 95.8 s; p = 0.056). DAP values for CBCT guidance and fluoroscopy were 514 and 174 mGy cm{sup 2}, respectively (p < 0.0001). There was a significant difference in favor of experienced CBCT guidance users regarding accuracy for both methods, procedure time of CBCT guidance, and added DAP values for fluoroscopy.ConclusionCBCT guidance allows users to perform PVP more accurately at the cost of higher patient dose and longer procedure time. Because procedural complications (e.g., cement leakage) are related to the accuracy of the needle placement, improvements in accuracy are clinically relevant. Training in CBCT guidance is essential to achieve greater accuracy and decrease procedure time/dose values.

  9. Over-the-catheter precut to gain access to the biliary duct during ERCP rendezvous.

    Science.gov (United States)

    Manes, Gianpiero; Baratti, Cinzia; Ardizzone, Sandro; Ferla, Fabio; Spiropoulos, Jean; Corsi, Fabio; Foschi, Diego; Trabucchi, Emilio; Bianchi Porro, Gabriele

    2008-10-01

    Endoscopic retrograde cholangiopancreatography (ERCP) rendezvous during laparoscopic cholecystectomy is an efficient and safe method to treat cholecystocholedocholithiasis. Advancing a guidewire through the cystic duct into the duodenum and withdrawing it in the accessory channel of duodenoscope may be, however, laborious. Moreover, rendezvous performed in the typical manner needs the use of several costly accessories. We herein describe a simpler and cheaper method to gain access to the biliary duct at rendezvous. Twenty-four consecutive patients undergoing ERCP rendezvous during laparoscopic cholecystectomy were considered. A catheter was introduced in the cystic duct and advanced into the duodenum. Access to the bile duct was than achieved by means of a precut sphincterotomy performed over the catheter emerging from the papilla. Cannulation was successful in all but two patients, in whom ERCP was performed in the conventional manner. The only complication was a case of mild post-sphincterotomy bleeding. In comparison with the typical rendezvous technique our procedure allowed savings of about 250, since its performance only requires a catheter and a knife sphincterotome. Over-the-catheter precut during ERCP rendezvous is a feasible and safe method which avoids the need for the manipulation of several accessories and guidewires, and thus results in money and time savings.

  10. Rendezvous and Docking Technology for Space Flight%空间交会对接技术

    Institute of Scientific and Technical Information of China (English)

    郑永煌

    2011-01-01

    空间交会对接是载人航天工程非常重要的基本技术.在介绍空间交会对接技术发展历史和中国首次交会对接取得圆满成功的基础上,阐述了空间交会对接技术的基本概念、技术难点、控制方式和交会对接过程,并着重介绍了四种交会对接机构的特点.最后介绍了中国首次交会对接任务规划、天宫一号目标飞行器和神舟八号飞船的特点以及两次空间交会对接过程.%Rendezvous and Docking is a very important basic technology of Manned Space Engineering. Firstly, rendezvous and docking technology development history is provided, and the significance of China first rendezvous and docking success is presented. Secondly, the basic conception, technology difficulty, control mode and docking process of rendezvous and docking technology are explained.Thirdly, four docking mechanism characteristics are special provided. Finally, China first rendezvous and docking mission planning,characteristic of Tiangong-1 target flight vehicle and Shenzhou-8 spacecraft and two rendezvous and docking successes are presented.

  11. The Connection Between Forms of Guidance for Inquiry-Based Learning and the Communicative Approaches Applied—a Case Study in the Context of Pre-service Teachers

    Science.gov (United States)

    Lehtinen, Antti; Lehesvuori, Sami; Viiri, Jouni

    2017-09-01

    Recent research has argued that inquiry-based science learning should be guided by providing the learners with support. The research on guidance for inquiry-based learning has concentrated on how providing guidance affects learning through inquiry. How guidance for inquiry-based learning could promote learning about inquiry (e.g. epistemic practices) is in need of exploration. A dialogic approach to classroom communication and pedagogical link-making offers possibilities for learners to acquire these practices. The focus of this paper is to analyse the role of different forms of guidance for inquiry-based learning on building the communicative approach applied in classrooms. The data for the study comes from an inquiry-based physics lesson implemented by a group of five pre-service primary science teachers to a class of sixth graders. The lesson was video recorded and the discussions were transcribed. The data was analysed by applying two existing frameworks—one for the forms of guidance provided and another for the communicative approaches applied. The findings illustrate that providing non-specific forms of guidance, such as prompts, caused the communicative approach to be dialogic. On the other hand, providing the learners with specific forms of guidance, such as explanations, shifted the communication to be more authoritative. These results imply that different forms of guidance provided by pre-service teachers can affect the communicative approach applied in inquiry-based science lessons, which affects the possibilities learners are given to connect their existing ideas to the scientific view. Future research should focus on validating these results by also analysing inservice teachers' lessons.

  12. Quality Assurance in University Guidance Services

    Science.gov (United States)

    Simon, Alexandra

    2014-01-01

    In Europe there is no common quality assurance framework for the delivery of guidance in higher education. Using a case study approach in four university career guidance services in England, France and Spain, this article aims to study how quality is implemented in university career guidance services in terms of strategy, standards and models,…

  13. A novel biased proportional navigation guidance law for close approach phase

    Directory of Open Access Journals (Sweden)

    Su Wenshan

    2016-02-01

    Full Text Available A novel biased proportional navigation guidance (BPNG law is proposed for the close approach phase, which aims to make the spacecraft rendezvous with the target in specific relative range and direction. Firstly, in order to describe the special guidance requirements, the concept of zero effort miss vector is proposed and the dangerous area where there exists collision risk for safety consideration is defined. Secondly, the BPNG, which decouples the range control and direction control, is designed in the line-of-sight (LOS rotation coordinate system. The theoretical analysis proves that BPNG meets guidance requirements quite well. Thirdly, for the consideration of fuel consumption, the optimal biased proportional navigation guidance (OBPNG law is derived by solving the Schwartz inequality. Finally, simulation results show that BPNG is effective for the close approach with the ability of evading the dangerous area and OBPNG consumes less fuel compared with BPNG.

  14. Hubble Servicing Challenges Drive Innovation of Shuttle Rendezvous Techniques

    Science.gov (United States)

    Goodman, John L.; Walker, Stephen R.

    2009-01-01

    Hubble Space Telescope (HST) servicing, performed by Space Shuttle crews, has contributed to what is arguably one of the most successful astronomy missions ever flown. Both nominal and contingency proximity operations techniques were developed to enable successful servicing, while lowering the risk of damage to HST systems, and improve crew safety. Influencing the development of these techniques were the challenges presented by plume impingement and HST performance anomalies. The design of both the HST and the Space Shuttle was completed before the potential of HST contamination and structural damage by shuttle RCS jet plume impingement was fully understood. Relative navigation during proximity operations has been challenging, as HST was not equipped with relative navigation aids. Since HST reached orbit in 1990, proximity operations design for servicing missions has evolved as insight into plume contamination and dynamic pressure has improved and new relative navigation tools have become available. Servicing missions have provided NASA with opportunities to gain insight into servicing mission design and development of nominal and contingency procedures. The HST servicing experiences and lessons learned are applicable to other programs that perform on-orbit servicing and rendezvous, both human and robotic.

  15. Asteroid Rendezvous Mission Design Using Multiobjective Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Ya-zhong Luo

    2014-01-01

    Full Text Available A new preliminary trajectory design method for asteroid rendezvous mission using multiobjective optimization techniques is proposed. This method can overcome the disadvantages of the widely employed Pork-Chop method. The multiobjective integrated launch window and multi-impulse transfer trajectory design model is formulated, which employes minimum-fuel cost and minimum-time transfer as two objective functions. The multiobjective particle swarm optimization (MOPSO is employed to locate the Pareto solution. The optimization results of two different asteroid mission designs show that the proposed approach can effectively and efficiently demonstrate the relations among the mission characteristic parameters such as launch time, transfer time, propellant cost, and number of maneuvers, which will provide very useful reference for practical asteroid mission design. Compared with the PCP method, the proposed approach is demonstrated to be able to provide much more easily used results, obtain better propellant-optimal solutions, and have much better efficiency. The MOPSO shows a very competitive performance with respect to the NSGA-II and the SPEA-II; besides a proposed boundary constraint optimization strategy is testified to be able to improve its performance.

  16. Pollinators' mating rendezvous and the evolution of floral advertisement.

    Science.gov (United States)

    Fishman, Michael A; Hadany, Lilach

    2013-01-07

    Successful cross-fertilization in plant species that rely on animal pollinators depends not just on the number of pollinator visits, but also on these visits' duration. Furthermore, in non-deceptive pollination, a visit's duration depends on the magnitude of the reward provided to the pollinator. Accordingly, plants that rely on biotic pollination have to partition their investment in cross-fertilization assurance between attracting pollinator visits - advertisement, and rewarding visitors to assure that the visit is of productive duration. Here we analyze these processes by a combination of optimality methods and game theoretical modeling. Our results indicate that the optimality in such allocation of resources depends on the types of reward offered to the pollinators. More precisely, we show that plants that offer both food reward and mating rendezvous to pollinators will evolve to allocate a higher proportion of their cross-fertilization assurance budget to advertisement than plants that offer only food reward. That is, our results indicate that pollinators' mating habits may play a role in floral evolution. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Impact of the Intracoronary Rendezvous technique on coronary angioplasty for chronic total occlusion.

    Science.gov (United States)

    Nihei, Taro; Yamamoto, Yoshito; Kudo, Shun; Hanawa, Kenichiro; Hasebe, Yuhi; Takagi, Yusuke; Minatoya, Yutaka; Sugi, Masafumi; Shimokawa, Hiroaki

    2017-10-01

    The Rendezvous technique, which requires bidirectional wiring, is one of the useful methods for improving the success rate of recanalization for chronic total occlusion (CTO) in the field of peripheral intervention. Recently, advanced new devices for percutaneous coronary intervention have enabled us to perform the Rendezvous technique for peripheral as well as for coronary CTO lesions. We used the Intracoronary Rendezvous technique to perform angioplasty for coronary CTO. "Intracoronary Rendezvous" means that Rendezvous was achieved within the CTO lesion. From March 2009 to November 2015, 189 patients underwent CTO angioplasty at our institute, and we treated 10 patients with the Intracoronary Rendezvous technique. This technique involves crossing the Gaia series guidewire to the contralateral Corsair microcatheter located inside the plaque of CTO lesions. The majority of the CTO sites examined were in the proximal RCA (60 %). Lesion length of the occlusion was relatively long (64.4 ± 12.2 mm). Using the biplane imaging system, we were able to control the Gaia guidewires in a specific direction. Furthermore, if the antegrade and retrograde wires can be advanced into contiguous space inside the CTO lesion, we intentionally entered either wire into the contralateral Corsair microcatheter, followed by successful CTO crossing. CTO recanalization was completed for all patients without controlled antegrade retrograde subintimal tracking (CART) or reverse CART. No major complications occurred during hospitalization. These results indicate that the Rendezvous technique, assisted by new devices and a biplane imaging system, represents one of the primary options to achieve successful coronary CTO recanalization.

  18. Protocol for the Electroencephalography Guidance of Anesthesia to Alleviate Geriatric Syndromes (ENGAGES) study: a pragmatic, randomised clinical trial

    Science.gov (United States)

    Wildes, T S; Winter, A C; Maybrier, H R; Mickle, A M; Lenze, E J; Stark, S; Lin, N; Inouye, S K; Schmitt, E M; McKinnon, S L; Muench, M R; Murphy, M R; Upadhyayula, R T; Fritz, B A; Escallier, K E; Apakama, G P; Emmert, D A; Graetz, T J; Stevens, T W; Palanca, B J; Hueneke, R L; Melby, S; Torres, B; Leung, J; Jacobsohn, E; Avidan, M S

    2016-01-01

    Introduction Postoperative delirium, arbitrarily defined as occurring within 5 days of surgery, affects up to 50% of patients older than 60 after a major operation. This geriatric syndrome is associated with longer intensive care unit and hospital stay, readmission, persistent cognitive deterioration and mortality. No effective preventive methods have been identified, but preliminary evidence suggests that EEG monitoring during general anaesthesia, by facilitating reduced anaesthetic exposure and EEG suppression, might decrease incident postoperative delirium. This study hypothesises that EEG-guidance of anaesthetic administration prevents postoperative delirium and downstream sequelae, including falls and decreased quality of life. Methods and analysis This is a 1232 patient, block-randomised, double-blinded, comparative effectiveness trial. Patients older than 60, undergoing volatile agent-based general anaesthesia for major surgery, are eligible. Patients are randomised to 1 of 2 anaesthetic approaches. One group receives general anaesthesia with clinicians blinded to EEG monitoring. The other group receives EEG-guidance of anaesthetic agent administration. The outcomes of postoperative delirium (≤5 days), falls at 1 and 12 months and health-related quality of life at 1 and 12 months will be compared between groups. Postoperative delirium is assessed with the confusion assessment method, falls with ProFaNE consensus questions and quality of life with the Veteran's RAND 12-item Health Survey. The intention-to-treat principle will be followed for all analyses. Differences between groups will be presented with 95% CIs and will be considered statistically significant at a two-sided pAnesthesia to Alleviate Geriatric Syndromes (ENGAGES) is approved by the ethics board at Washington University. Recruitment began in January 2015. Dissemination plans include presentations at scientific conferences, scientific publications, internet-based educational materials and

  19. Shared control on lunar spacecraft teleoperation rendezvous operations with large time delay

    Science.gov (United States)

    Ya-kun, Zhang; Hai-yang, Li; Rui-xue, Huang; Jiang-hui, Liu

    2017-08-01

    Teleoperation could be used in space on-orbit serving missions, such as object deorbits, spacecraft approaches, and automatic rendezvous and docking back-up systems. Teleoperation rendezvous and docking in lunar orbit may encounter bottlenecks for the inherent time delay in the communication link and the limited measurement accuracy of sensors. Moreover, human intervention is unsuitable in view of the partial communication coverage problem. To solve these problems, a shared control strategy for teleoperation rendezvous and docking is detailed. The control authority in lunar orbital maneuvers that involves two spacecraft as rendezvous and docking in the final phase was discussed in this paper. The predictive display model based on the relative dynamic equations is established to overcome the influence of the large time delay in communication link. We discuss and attempt to prove via consistent, ground-based simulations the relative merits of fully autonomous control mode (i.e., onboard computer-based), fully manual control (i.e., human-driven at the ground station) and shared control mode. The simulation experiments were conducted on the nine-degrees-of-freedom teleoperation rendezvous and docking simulation platform. Simulation results indicated that the shared control methods can overcome the influence of time delay effects. In addition, the docking success probability of shared control method was enhanced compared with automatic and manual modes.

  20. Public Policies for Career Development. Case Studies And Emerging Issues For Designing Career Information And Guidance Systems In Developing And Transition Economies

    Science.gov (United States)

    Watts, A. G.; Fretwell, David H.

    2004-01-01

    The following pages summarize the findings of seven case-studies of public policy in career guidance carried out in Chile, the Philippines, Poland, Romania, Russia, South Africa and Turkey. The objectives of this World Bank study were: to identify and describe the distinctive issues faced by developing and transition economies in forming effective…

  1. Vocational Guidance for Equal Access and Opportunity for Girls and Women in Technical and Vocational Education. UNEVOC Studies in Technical and Vocational Education 6.

    Science.gov (United States)

    Miller, Juliet V.; Vetter, Louise

    A study examined the relevance of vocational information and guidance for the equal access of girls and women to technical/vocational education in the following countries: Argentina; India; Mexico; Republic of Korea; South Africa; Spain; Sweden; Turkey; United Arab Emirates; and Zambia. Case studies were conducted by using a multiple-strategy…

  2. A guidance law for UAV autonomous aerial refueling based on the iterative computation method

    Directory of Open Access Journals (Sweden)

    Luo Delin

    2014-08-01

    Full Text Available The rendezvous and formation problem is a significant part for the unmanned aerial vehicle (UAV autonomous aerial refueling (AAR technique. It can be divided into two major phases: the long-range guidance phase and the formation phase. In this paper, an iterative computation guidance law (ICGL is proposed to compute a series of state variables to get the solution of a control variable for a UAV conducting rendezvous with a tanker in AAR. The proposed method can make the control variable converge to zero when the tanker and the UAV receiver come to a formation flight eventually. For the long-range guidance phase, the ICGL divides it into two sub-phases: the correction sub-phase and the guidance sub-phase. The two sub-phases share the same iterative process. As for the formation phase, a velocity coordinate system is created by which control accelerations are designed to make the speed of the UAV consistent with that of the tanker. The simulation results demonstrate that the proposed ICGL is effective and robust against wind disturbance.

  3. A comparative study to evaluate the discrepancy in condylar guidance values between two commercially available arcon and non-arcon articulators: A clinical study

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar Goyal

    2011-01-01

    Full Text Available Aim: The purpose of this study was comparative evaluation of sagittal condylar values of arcon and non-arcon articulators with cephalometric readings and to determine the amount of discrepancy in sagittal condylar guidance values between arcon and non-arcon articulators using same protrusive record. Materials and Methods: Twenty subjects in the age group of 19-35 years, free from temporomandibular joint dysfunction, and occlusal disharmony, with healthy dentition participated in the study. Hanau H2 (non-arcon type and Hanau Wide-Vue (arcon type articulators were programmed for sagittal condylar guidance values using the same protrusive record made in polysiloxane bite registration material with edge to edge degree of protrusion. The resultant values for both the articulators on either side were compared with values obtained from tracing of digital lateral cephalogram using Kodak Dental imaging Window software 6.6.3.0-C program. The tabulated data were subjected to statistical analysis, ANOVA (Fishers ′F′ test for group comparison, Tukey′s HSD test for inter-comparison, student′s unpaired ′t′ test for intra-group comparison, and level of significance (P was calculated using the same. Results: The mean sagittal condylar guidance values of the three different groups were found to be very highly significant (P=0.001 and highly significant (P=0.002 on the right and left sides respectively. There was a very highly significant difference (P=0.001 and highly significant difference (P=0.003 between the arcon and non-arcon group on the right and left side respectively. No significant difference was found between the arcon and cephalometric group (P=0.284 right, P=0.853 left and a statistically significant difference was found between the non-arcon and cephalometric group (P=0.049 right, P=0.015 left. On intragroup comparison there was no statistically significant difference in sagittal condylar values on the right and left sides. Conclusion

  4. Manned maneuvering unit applications for automated rendezvous and capture

    Science.gov (United States)

    Brehm, Donald L.; Cuseo, John A.; Lenda, Joseph A.; Ray, Lex; Whitsett, C. Edward

    Automated Rendezvous and Capture (AR&C) is an important technology to multiple National Aeronautics and Space Administration (NASA) programs and centers. The recent Johnson Spacecraft Center (JSC) AR&C Quality Function Deployment (QFD) has listed on-orbit demonstration of related technologies as a near term priority. Martin Marietta has been evaluating use of the Manned Maneuvering Unit (MMU) for a low cost near term on-orbit demonstration of AR&C technologies such as control algorithms, sensors, and processors as well as system level performance. The MMU Program began in 1979 as the method of repairing the Space Shuttle (STS) Thermal Protection System (the tiles). The units were not needed for this task, but were successfully employed during three Shuttle flights in 1984: a test flight was flown in in February as proof of concept, in April the MMU participated in the Solar Max Repair Mission, and in November the MMU's returned to space to successfully rescue the two errant satellites, Westar and Palapa. In the intervening years, the MMU simulator and MMU Qualification Test Unit (QTU) have been used for Astronaut training and experimental evaluations. The Extra-Vehicular Activities (EVA) Retriever has used the QTU, in an unmanned form, as a free-flyer on the Johnson Space Center (JSC) Precision Air Bearing Floor (PABF). Currently, the MMU is undergoing recertification for flight. The two flight units were removed from storage in September, 1991 and evaluation tests were performed. The tests demonstrated that the units are in good shape with no discrepancies that would preclude further use. The Return to Flight effort is currently clearing up recertification issues and evaluating the design against the present Shuttle environments.

  5. Prepared to practice? Perception of career preparation and guidance of recent medical graduates at two campuses of a transnational medical school: a cross-sectional study.

    Science.gov (United States)

    Kassim, Sameer S; McGowan, Yvonne; McGee, Hannah; Whitford, David L

    2016-02-09

    Graduating medical students enter the workforce with substantial medical knowledge and experience, yet little is known about how well they are prepared for the transition to medical practice in diverse settings. We set out to compare perceptions of medical school graduates' career guidance with their perceptions of preparedness to practice as interns. We also set out to compare perceptions of preparedness for hospital practice between graduates from two transnational medical schools. This was a cross-sectional study. A Preparedness for Hospital Practice (PHPQ) survey and career guidance questionnaire was sent to recent medical graduates, incorporating additional free text responses on career preparation. Data was analyzed using descriptive statistics and tests of association including Chi-square, Mann-Whitney U and Kruskal-Wallis H tests. Forty three percent (240/555) of graduates responded to the survey: 39 % of respondents were domestic (Dublin, Ireland or Manama, Kingdom of Bahrain) and interning locally; 15 % were overseas students interning locally; 42 % were overseas students interning internationally and 4 % had not started internship. Two variables explained 13 % of the variation in preparedness for hospital practice score: having planned postgraduate education prior to entering medical school and having helpful career guidance in medical school. Overseas graduates interning internationally were more likely to have planned their postgraduate career path prior to entering medical school. Dublin graduates found their career guidance more helpful than Bahrain counterparts. The most cited shortcomings were lack of structured career advice and lack of advice on the Irish and Bahraini postgraduate systems. This study has demonstrated that early consideration of postgraduate career preparation and helpful medical school career guidance has a strong association with perceptions of preparedness of medical graduates for hospital practice. In an era of increasing

  6. Using maize as a model to study pollen tube growth and guidance, cross-incompatibility and sperm delivery in grasses.

    Science.gov (United States)

    Dresselhaus, Thomas; Lausser, Andreas; Márton, Mihaela L

    2011-09-01

    In contrast to animals and lower plants such as mosses and ferns, sperm cells of flowering plants (angiosperms) are immobile and require transportation to the female gametes via the vegetative pollen tube cell to achieve double fertilization. The path of the pollen tube towards the female gametophyte (embryo sac) has been intensively studied in many intra- and interspecific crossing experiments with the aim of increasing the gene pool of crop plants for greater yield, improved biotic and abiotic stress resistance, and for introducing new agronomic traits. Many attempts to hybridize different species or genotypes failed due to the difficulty for the pollen tubes in reaching the female gametophyte. Detailed studies showed that these processes are controlled by various self-incompatible (intraspecific) and cross-incompatible (interspecific) hybridization mechanisms. Understanding the molecular mechanisms of crossing barriers is therefore of great interest in plant reproduction, evolution and breeding research. In particular, pre-zygotic hybridization barriers related to pollen tube germination, growth, guidance and sperm delivery, which are considered the major hybridization controls in nature and thus also contribute to species isolation and speciation, have been intensively investigated. Despite this general interest, surprisingly little is known about these processes in the most important agronomic plant family, the Gramineae, Poaceae or grasses. Small polymorphic proteins and their receptors, degradation of sterility locus proteins and general compounds such as calcium, γ-aminobutyric acid or nitric oxide have been shown to be involved in progamic pollen germination, adhesion, tube growth and guidance, as well as sperm release. Most advances have been made in the Brassicaceae, Papaveraceae, Linderniaceae and Solanaceae families including their well-understood self-incompatibility (SI) systems. Grass species evolved similar mechanisms to control the penetration

  7. Graphic Turbulence Guidance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Forecast turbulence hazards identified by the Graphical Turbulence Guidance algorithm. The Graphical Turbulence Guidance product depicts mid-level and upper-level...

  8. Graphical Turbulence Guidance - Composite

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Forecast turbulence hazards identified by the Graphical Turbulence Guidance algorithm. The Graphical Turbulence Guidance product depicts mid-level and upper-level...

  9. Career guidance in communities

    DEFF Research Database (Denmark)

    Thomsen, Rie

    for the development of a critically reflexive career guidance practice. The considerations are organised around seven elements. 1. Creating opportunity, structure and access 2. Entering a community and increasing visibility 3. Providing guidance in communities 4. Exploring potentials in guidance situations 5...... in career guidance practices as well as in the lives of the people in the communities. This paper falls into two parts: The first part considers the collective as the starting point for the development of meaningful career guidance activities. Based on previous research on career guidance in communities......The aim of this paper is to inspire practitioners and professionals to leave their offices to bring career guidance into communities that might not identify with career guidance in the first instance. By making the effort to engage with communities, practitioners may bring about a critical change...

  10. Maximising the impact of qualitative research in feasibility studies for randomised controlled trials: guidance for researchers

    NARCIS (Netherlands)

    O’Cathain, A.; Hoddinott, P.; Lewin, S.; Thomas, K.J.; Young, B.; Adamson, J.; Jansen, J.F.M.; Mills, N.; Moore, G.; Donovan, J.L.

    2015-01-01

    Feasibility studies are increasingly undertaken in preparation for randomised controlled trials in order to explore uncertainties and enable trialists to optimise the intervention or the conduct of the trial. Qualitative research can be used to examine and address key uncertainties prior to a full

  11. Interesting rendezvous location in a liver transplantation patient with anastomosis stricture.

    Science.gov (United States)

    Odemis, Bulent; Oztas, Erkin; Yurdakul, Mehmet; Torun, Serkan; Suna, Nuredtin; Kayacetin, Ertugrul

    2014-11-14

    An endoscopic or radiologic percutaneous approach may be an initial minimally invasive method for treating biliary strictures after living donor liver transplantation; however, cannulation of biliary strictures is sometimes difficult due to the presence of a sharp or twisted angle within the stricture or a complete stricture. When an angulated or twisted biliary stricture interrupts passage of a guidewire over the stricture, it is difficult to replace the percutaneous biliary drainage catheter with inside stents by endoscopic retrograde cholangiopancreatography. The rendezvous technique can be used to overcome this difficulty. In addition to the classical rendezvous method, in cases with complete transection of the common bile duct a modified technique involving the insertion of a snare into the subhepatic space has been successfully performed. Herein, we report a modified rendezvous technique in the duodenal bulb as an extraordinary location for a patient with duct-to-duct anastomotic complete stricture after liver transplantation.

  12. Quorum system and random based asynchronous rendezvous protocol for cognitive radio ad hoc networks

    Directory of Open Access Journals (Sweden)

    Sylwia Romaszko

    2013-12-01

    Full Text Available This paper proposes a rendezvous protocol for cognitive radio ad hoc networks, RAC2E-gQS, which utilizes (1 the asynchronous and randomness properties of the RAC2E protocol, and (2 channel mapping protocol, based on a grid Quorum System (gQS, and taking into account channel heterogeneity and asymmetric channel views. We show that the combination of the RAC2E protocol with the grid-quorum based channel mapping can yield a powerful RAC2E-gQS rendezvous protocol for asynchronous operation in a distributed environment assuring a rapid rendezvous between the cognitive radio nodes having available both symmetric and asymmetric channel views. We also propose an enhancement of the protocol, which uses a torus QS for a slot allocation, dealing with the worst case scenario, a large number of channels with opposite ranking lists.

  13. Pedicle Screw Insertion Accuracy Using O-Arm, Robotic Guidance, or Freehand Technique: A Comparative Study.

    Science.gov (United States)

    Laudato, Pietro Aniello; Pierzchala, Katarzyna; Schizas, Constantin

    2018-03-15

    A retrospective radiological study. The aim of this study was to evaluate the accuracy of pedicle screw insertion using O-Arm navigation, robotic assistance, or a freehand fluoroscopic technique. Pedicle screw insertion using either "O-Arm" navigation or robotic devices is gaining popularity. Although several studies are available evaluating each of those techniques separately, no direct comparison has been attempted. Eighty-four patients undergoing implantation of 569 lumbar and thoracic screws were divided into three groups. Eleven patients (64 screws) had screws inserted using robotic assistance, 25 patients (191 screws) using the O-arm, while 48 patients (314 screws) had screws inserted using lateral fluoroscopy in a freehand technique. A single experienced spine surgeon assisted by a spinal fellow performed all procedures. Screw placement accuracy was assessed by two independent observers on postoperative computed tomography (CTs) according to the A to D Rampersaud criteria. No statistically significant difference was noted between the three groups. About 70.4% of screws in the freehand group, 69.6% in the O arm group, and 78.8% in the robotic group were placed completely within the pedicle margins (grade A) (P > 0.05). About 6.4% of screws were considered misplaced (grades C&D) in the freehand group, 4.2% in the O-arm group, and 4.7% in the robotic group (P > 0.05). The spinal fellow inserted screws with the same accuracy as the senior surgeon (P > 0.05). The advent of new technologies does not appear to alter accuracy of screw placement in our setting. Under supervision, spinal fellows might perform equally well to experienced surgeons using new tools. The lack of difference in accuracy does not imply that the above-mentioned techniques have no added advantages. Other issues, such as surgeon/patient radiation, fiddle factor, teaching suitability, etc., outside the scope of our present study, need further assessment. 3.

  14. Practical guidance material for the development, energy and climate country studies

    Energy Technology Data Exchange (ETDEWEB)

    Halsnaes, K.; Garg, A.; Olhoff, A.; Denton, F.

    2006-10-15

    The document is developed as part of the Development, Energy and Climate project in order to facilitate methodological consistency and the use of common assumptions in national case studies in Bangladesh, Brazil, China, India, Senegal and South Africa that are conducted as part of the project. In addition to this document the project and country studies are also based on in depth thematic work in three areas namely; 1) Development pathways and climate change; 2) Assessment of Policy Instruments in the Context of Current Market Structure, Institutional Capacities and Risks in Developing Countries; 3) Climate change impacts, vulnerability, and adaptation in the energy sector with a special emphasis given to linkages between adaptation and mitigation policies. The Development, Energy, and Climate project will identify promising energy policy options in the participating countries that are consistent with their national sustainable development objectives. The project teams from Bangladesh, Brazil, China, India, South Africa and Senegal will examine how energy sector policies can be evaluated using specific sustainable development indicators and existing analytical approaches and tools relevant to the countries. The country studies will address energy sector issues, adaptation policies, and alternative scenarios for technology penetration processes. The policy options and the sustainable development impacts of implementing these will be discussed in national stakeholder dialogues with broad participation of government, private sector and NGOs. Cross-country interactions about conceptual and common methodological issues will be covered in three thematic papers. The project will produce a synthesis of the country case studies as an input to various international processes in order to build support for approaches that integrate sustainable development, energy and climate policies. (au)

  15. Methodology for Developing a Probabilistic Risk Assessment Model of Spacecraft Rendezvous and Dockings

    Science.gov (United States)

    Farnham, Steven J., II; Garza, Joel, Jr.; Castillo, Theresa M.; Lutomski, Michael

    2011-01-01

    In 2007 NASA was preparing to send two new visiting vehicles carrying logistics and propellant to the International Space Station (ISS). These new vehicles were the European Space Agency s (ESA) Automated Transfer Vehicle (ATV), the Jules Verne, and the Japanese Aerospace and Explorations Agency s (JAXA) H-II Transfer Vehicle (HTV). The ISS Program wanted to quantify the increased risk to the ISS from these visiting vehicles. At the time, only the Shuttle, the Soyuz, and the Progress vehicles rendezvoused and docked to the ISS. The increased risk to the ISS was from an increase in vehicle traffic, thereby, increasing the potential catastrophic collision during the rendezvous and the docking or berthing of the spacecraft to the ISS. A universal method of evaluating the risk of rendezvous and docking or berthing was created by the ISS s Risk Team to accommodate the increasing number of rendezvous and docking or berthing operations due to the increasing number of different spacecraft, as well as the future arrival of commercial spacecraft. Before the first docking attempt of ESA's ATV and JAXA's HTV to the ISS, a probabilistic risk model was developed to quantitatively calculate the risk of collision of each spacecraft with the ISS. The 5 rendezvous and docking risk models (Soyuz, Progress, Shuttle, ATV, and HTV) have been used to build and refine the modeling methodology for rendezvous and docking of spacecrafts. This risk modeling methodology will be NASA s basis for evaluating the addition of future ISS visiting spacecrafts hazards, including SpaceX s Dragon, Orbital Science s Cygnus, and NASA s own Orion spacecraft. This paper will describe the methodology used for developing a visiting vehicle risk model.

  16. Card Sort Technique in Vocational Guidance/Career Counseling: Pilot Study about Career Values

    OpenAIRE

    Tülin ACAR; Yalçın DEMİR; Fidan KORKUT; Özlem HASKAN; Tuğba KABALCI; Dilşad KUTSAL; İlker Mustafa PEKİN; Esra TURHAN

    2009-01-01

    The purpose of this study was to develop and to pilot a not-test technique for assessing career and work values. This instrument was developed during a Career Counseling course taught by one of the authors of this paper. The first stage of development was the generation of a master list of career and work values, as reflected in the current literature related to theories and vocational research. From this master list 38 career values were selected resulting in the final deck that was used i...

  17. Using a natural abilities battery for academic and career guidance: a ten-year study.

    Science.gov (United States)

    Brown, Corrie C; Harvey, Stephen B; Stiles, Dori

    2011-01-01

    Over a period of 10 years, first-year students from 11 consecutive veterinary classes conducted a self-assessment using a natural abilities survey. The present study analyzes the data compiled from students' self-assessment results. As a group, veterinary students are exceptional problem solvers, either through inductive or deductive reasoning, and have strong spatial relations capacities. Veterinary students have a range of learning styles with design memory being the primary vehicle for information delivery and tonal memory being the least frequently used style overall. Information gained on each student's natural abilities can be used to guide effective career decision making and enhance prospects for long-term career satisfaction.

  18. The influence of spatial ability and experience on performance during spaceship rendezvous and docking.

    Science.gov (United States)

    Du, Xiaoping; Zhang, Yijing; Tian, Yu; Huang, Weifen; Wu, Bin; Zhang, Jingyu

    2015-01-01

    Manual rendezvous and docking (manual RVD) is a challenging space task for astronauts. Previous research showed a correlation between spatial ability and manual RVD skills among participants at early stages of training, but paid less attention to experts. Therefore, this study tried to explore the role of spatial ability in manual RVD skills in two groups of trainees, one relatively inexperienced and the other experienced operators. Additionally, mental rotation has been proven essential in RVD and was tested in this study among 27 male participants, 15 novices, and 12 experts. The participants performed manual RVD tasks in a high fidelity simulator. Results showed that experience moderated the relation between mental rotation ability and manual RVD performance. On one hand, novices with high mental rotation ability tended to perform that RVD task more successfully; on the other hand, experts with high mental rotation ability showed not only no performance advantage in the final stage of the RVD task, but had certain disadvantages in their earlier processes. Both theoretical and practical implications were discussed.

  19. The Influence of Spatial Ability and Experience on Spacecraft Rendezvous and Docking Operation Performance

    Directory of Open Access Journals (Sweden)

    Xiaoping eDu

    2015-07-01

    Full Text Available Manual rendezvous and docking (manual RVD is a challenging space task for astronauts. Previous research showed a correlation between spatial ability and manual RVD skills among participants at early stages of training, but paid less attention to experts. Therefore, this study tried to explore the role of spatial ability in manual RVD skills in two groups of trainees, one relatively inexperienced and the other experienced operators. Additionally, mental rotation has been proven essential in RVD and was tested in this study among 27 male participants, 15 novices and 12 experts. The participants performed manual RVD tasks in a high fidelity simulator. Results showed that experience moderated the relation between mental rotation ability and manual RVD performance. On one hand, novices with high mental rotation ability tended to perform that RVD task more successfully; on the other hand, experts with high mental rotation ability showed not only no performance advantage in the final stage of the RVD task, but had certain disadvantages in their earlier processes. Both theoretical and practical implications were discussed.

  20. The influence of spatial ability and experience on performance during spaceship rendezvous and docking

    Science.gov (United States)

    Du, Xiaoping; Zhang, Yijing; Tian, Yu; Huang, Weifen; Wu, Bin; Zhang, Jingyu

    2015-01-01

    Manual rendezvous and docking (manual RVD) is a challenging space task for astronauts. Previous research showed a correlation between spatial ability and manual RVD skills among participants at early stages of training, but paid less attention to experts. Therefore, this study tried to explore the role of spatial ability in manual RVD skills in two groups of trainees, one relatively inexperienced and the other experienced operators. Additionally, mental rotation has been proven essential in RVD and was tested in this study among 27 male participants, 15 novices, and 12 experts. The participants performed manual RVD tasks in a high fidelity simulator. Results showed that experience moderated the relation between mental rotation ability and manual RVD performance. On one hand, novices with high mental rotation ability tended to perform that RVD task more successfully; on the other hand, experts with high mental rotation ability showed not only no performance advantage in the final stage of the RVD task, but had certain disadvantages in their earlier processes. Both theoretical and practical implications were discussed. PMID:26236252

  1. Robust H ∞ Control for Spacecraft Rendezvous with a Noncooperative Target

    Science.gov (United States)

    Wu, Shu-Nan; Zhou, Wen-Ya; Tan, Shu-Jun; Wu, Guo-Qiang

    2013-01-01

    The robust H ∞ control for spacecraft rendezvous with a noncooperative target is addressed in this paper. The relative motion of chaser and noncooperative target is firstly modeled as the uncertain system, which contains uncertain orbit parameter and mass. Then the H ∞ performance and finite time performance are proposed, and a robust H ∞ controller is developed to drive the chaser to rendezvous with the non-cooperative target in the presence of control input saturation, measurement error, and thrust error. The linear matrix inequality technology is used to derive the sufficient condition of the proposed controller. An illustrative example is finally provided to demonstrate the effectiveness of the controller. PMID:24027446

  2. Observer-Based Robust Control for Spacecraft Rendezvous with Thrust Saturation

    Directory of Open Access Journals (Sweden)

    Neng Wan

    2014-01-01

    Full Text Available This paper proposes an observer-based robust guaranteed cost control method for thrust-limited rendezvous in near-circular orbits. Treating the noncircularity of the target orbit as a parametric uncertainty, a linearized motion model derived from the two-body problem is adopted as the controlled plant. Based on this model, a robust guaranteed cost observer-controller is synthesized with a less conservative saturation control law, and sufficient condition for the existence of this observer-based rendezvous controller is derived. Finally, an illustrative example with immeasurable velocity states is presented to demonstrate the advantages and effectiveness of the control scheme.

  3. Card Sort Technique in Vocational Guidance/Career Counseling: Pilot Study about Career Values

    Directory of Open Access Journals (Sweden)

    Tülin ACAR

    2009-08-01

    Full Text Available The purpose of this study was to develop and to pilot a not-test technique for assessing career and work values. This instrument was developed during a Career Counseling course taught by one of the authors of this paper. The first stage of development was the generation of a master list of career and work values, as reflected in the current literature related to theories and vocational research. From this master list 38 career values were selected resulting in the final deck that was used in testing. This deck of cards was given the name Career Values Cards (MEDEK and administered to a total of 75 high school students. Following administration each of the subjects was asked to complete a MEDEK evaluation form designed to assess reactions to the MEDEK experience. Results of the survey indicated that the MEDEK was an easy-to-use, understandable, and enjoyable technique to increase self-awareness and enhance insight, and a source of important information for students engaged in career counseling and career development by enhancing personal identification of personal career and work values.

  4. Iodine and Pregnancy—A Qualitative Study Focusing on Dietary Guidance and Information

    Directory of Open Access Journals (Sweden)

    Maria Bouga

    2018-03-01

    Full Text Available Iodine is essential for thyroid hormones synthesis and normal neurodevelopment; however, ~60% of pregnant women do not meet the WHO (World Health Organization recommended intake. Using a qualitative design, we explored the perceptions, awareness, and experiences of pregnancy nutrition, focusing on iodine. Women in the perinatal period (n = 48 were interviewed and filled in a food frequency questionnaire for iodine. Almost all participants achieved the recommended 150 μg/day intake for non-pregnant adults (99%, but only 81% met the increased demands of pregnancy (250 μg/day. Most were unaware of the importance, sources of iodine, and recommendations for iodine intake. Attitudes toward dairy products consumption were positive (e.g., helps with heartburn; easy to increase. Increased fish consumption was considered less achievable, with barriers around taste, smell, heartburn, and morning sickness. Community midwives were the main recognised provider of dietary advice. The dietary advice received focused most often on multivitamin supplements rather than food sources. Analysis highlighted a clear theme of commitment to change behaviour, motivated by pregnancy, with a desired focus on user-friendly documentation and continued involvement of the health services. The study highlights the importance of redirecting advice on dietary requirements in pregnancy and offers practical suggestions from women in the perinatal period as the main stakeholder group.

  5. A comparative evaluation of static and functional methods for recording centric relation and condylar guidance: a clinical study.

    Science.gov (United States)

    Thakur, Mridul; Jain, Veena; Parkash, Hari; Kumar, Pravesh

    2012-09-01

    To evaluate and compare the centric relation and horizontal condylar guidance using interocclusal wax and extra oral Gothic arch methods and subjective evaluation of dentures thus fabricated. Centric relation and horizontal condylar guidance was recorded by using interocclusal wax and gothic arch tracing in 28 completely edentulous patients. These records were transferred to the articulator and difference in both values was recorded. After that patients were divided in two groups according to the centric relation and horizontal condylar guidance recording method used to achieve balanced occlusion. Response of the dentures was subjectively evaluated using "Woelfel subjective evaluation criteria". Centric relation recorded by both the methods did coincide in 7.14 % of patients. Centric relation recorded by interocclusal wax was posterior to Gothic centric relation in 21.43 % of patients, and anterior to Gothic centric relation in 71.42 % patients. Gothic arch tracings gave higher mean guidance values on both the sides as compared to protrusive wax record in all the subjects, although the difference was statistically insignificant (P > 0.05). Subjective evaluation showed statistical insignificance for all the parameters in both groups. Gothic arch method records the centric relation at a more posterior position than the Static method, but it does not make any difference in clinical performance of the complete denture. Horizontal condylar guidance angle was approximately similar by both the methods.

  6. A PROSPECTIVE STUDY ON LIFESTYLE GUIDANCE AND USE OF MANAGEMENT FORMS FOR FOOD ALLERGY IN LICENSED NURSERY SCHOOLS.

    Science.gov (United States)

    Yanagida, Noriyuki; Sato, Sakura; Murata, Junko; Seto, Akiko; Nishisako, Shin; Ebisawa, Motohiro

    2016-01-01

    There have been no reports on the use of "foods allergy disease lifestyle guidance and management forms at day care centers" (life management guidance forms) for understanding details of pupils with food allergies. The contents of lifestyle management guidance forms obtained in Sagamihara city from licensed nurseries were investigated prospectively. We compared and analyzed for the use of life management guidance forms initially in 2013 and in the fiscal year of 2014 in Sagamihara city licensed nurseries. In all, in 2013 and 2014, 9,567 and 10,069 pupils were included in licensed nurseries, and 426 (4.5%) and 447 (4.4%) pupils had food allergies, 61 (0.6%) and 61 (0.6%) had anaphylaxis, respectively.The causative foods in 2013 and 2014, respectively, included unheated hen's egg in 71.6% and 69.6%; heated hen's egg in 54.2% and 54.8%; milk in 23.0% and 23.3%; peanuts in 17.8% and 17.0%; buckwheat in 7.3% and 8.5%; and wheat in 6.3% and 8.3%. There are no significant differences in the distribution of causative foods between 2013 and 2014.Immediate-type food allergy was significantly more frequent in 2014 than in 2013 (73.0% and 78.8%, respectively; p=0.040). Using a life management guidance form will make it easier to manage food allergies in children.

  7. Handling Neighbor Discovery and Rendezvous Consistency with Weighted Quorum-Based Approach.

    Science.gov (United States)

    Own, Chung-Ming; Meng, Zhaopeng; Liu, Kehan

    2015-09-03

    Neighbor discovery and the power of sensors play an important role in the formation of Wireless Sensor Networks (WSNs) and mobile networks. Many asynchronous protocols based on wake-up time scheduling have been proposed to enable neighbor discovery among neighboring nodes for the energy saving, especially in the difficulty of clock synchronization. However, existing researches are divided two parts with the neighbor-discovery methods, one is the quorum-based protocols and the other is co-primality based protocols. Their distinction is on the arrangements of time slots, the former uses the quorums in the matrix, the latter adopts the numerical analysis. In our study, we propose the weighted heuristic quorum system (WQS), which is based on the quorum algorithm to eliminate redundant paths of active slots. We demonstrate the specification of our system: fewer active slots are required, the referring rate is balanced, and remaining power is considered particularly when a device maintains rendezvous with discovered neighbors. The evaluation results showed that our proposed method can effectively reschedule the active slots and save the computing time of the network system.

  8. Handling Neighbor Discovery and Rendezvous Consistency with Weighted Quorum-Based Approach

    Directory of Open Access Journals (Sweden)

    Chung-Ming Own

    2015-09-01

    Full Text Available Neighbor discovery and the power of sensors play an important role in the formation of Wireless Sensor Networks (WSNs and mobile networks. Many asynchronous protocols based on wake-up time scheduling have been proposed to enable neighbor discovery among neighboring nodes for the energy saving, especially in the difficulty of clock synchronization. However, existing researches are divided two parts with the neighbor-discovery methods, one is the quorum-based protocols and the other is co-primality based protocols. Their distinction is on the arrangements of time slots, the former uses the quorums in the matrix, the latter adopts the numerical analysis. In our study, we propose the weighted heuristic quorum system (WQS, which is based on the quorum algorithm to eliminate redundant paths of active slots. We demonstrate the specification of our system: fewer active slots are required, the referring rate is balanced, and remaining power is considered particularly when a device maintains rendezvous with discovered neighbors. The evaluation results showed that our proposed method can effectively reschedule the active slots and save the computing time of the network system.

  9. Dynamical analysis of rendezvous and docking with very large space infrastructures in non-Keplerian orbits

    Science.gov (United States)

    Colagrossi, Andrea; Lavagna, Michèle

    2018-03-01

    A space station in the vicinity of the Moon can be exploited as a gateway for future human and robotic exploration of the solar system. The natural location for a space system of this kind is about one of the Earth-Moon libration points. The study addresses the dynamics during rendezvous and docking operations with a very large space infrastructure in an EML2 Halo orbit. The model takes into account the coupling effects between the orbital and the attitude motion in a circular restricted three-body problem environment. The flexibility of the system is included, and the interaction between the modes of the structure and those related with the orbital motion is investigated. A lumped parameter technique is used to represents the flexible dynamics. The parameters of the space station are maintained as generic as possible, in a way to delineate a global scenario of the mission. However, the developed model can be tuned and updated according to the information that will be available in the future, when the whole system will be defined with a higher level of precision.

  10. Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

    International Nuclear Information System (INIS)

    Laurent, Alexis; Clavreul, Julie; Bernstad, Anna; Bakas, Ioannis; Niero, Monia; Gentil, Emmanuel; Christensen, Thomas H.; Hauschild, Michael Z.

    2014-01-01

    Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • We analyse the past LCA practice against the ISO standard and ILCD Handbook guidance. • Malpractices exist in many methodological aspects with large variations among studies. • Many of these aspects are important for the reliability of the results. • We provide detailed recommendations to practitioners of waste management LCAs. - Abstract: Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs

  11. Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

    Energy Technology Data Exchange (ETDEWEB)

    Laurent, Alexis, E-mail: alau@dtu.dk [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Clavreul, Julie [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Bernstad, Anna [Water and Environmental Engineering, Department of Chemical Engineering, Lund University, 221 00 Lund (Sweden); Bakas, Ioannis [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Niero, Monia [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); ECO – Ecosystems and Environmental Sustainability, Department of Chemical and Biochemical Engineering, Technical University of Denmark, 4000 Roskilde (Denmark); Gentil, Emmanuel [Copenhagen Resource Institute, 1215 Copenhagen K (Denmark); Christensen, Thomas H. [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Hauschild, Michael Z. [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2014-03-01

    Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • We analyse the past LCA practice against the ISO standard and ILCD Handbook guidance. • Malpractices exist in many methodological aspects with large variations among studies. • Many of these aspects are important for the reliability of the results. • We provide detailed recommendations to practitioners of waste management LCAs. - Abstract: Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.

  12. RESEARCH GUIDANCE STUDIES

    International Nuclear Information System (INIS)

    Unknown

    2000-01-01

    During this quarter, in task area 1, work was performed on three separate areas of activity. These were (1) review of the proposed and final EPA Tier 2 regulations, (2) assistance in preparation of an ultra-clean transportation fuels report for the deputy assistant secretary for Fossil Energy, (3) preparation of a detailed trip report from attending the Clean Fuels 2000 conference in San Diego. In task area 4, three activities were undertaken: an update of coproduction, an analysis of the potential for gasification of petroleum coke in U.S. refineries, and preparation and presentation of a paper at the Coal Utilization and Fuel Systems conference in Clearwater. In task area 5, a presentation was prepared for the American Association of Petroleum Geologists (AAPG) Annual Convention to be held in New Orleans in April. This presentation was an overview of GTL technology including the current costs and product values. In addition the potential risks of the technology were addressed and the potential contribution of GTL products to the future world fuel market was discussed

  13. Effect of Professionalism, Competence, Knowledge of Financial Management, and Intensity Guidance Apparatus Inspectorate for Quality of Financial Statements (Study on Inspectorate Regencies/Cities in Aceh

    Directory of Open Access Journals (Sweden)

    Darwanis Darwanis

    2016-04-01

    Full Text Available This research aims to: 1. Examine the influence of professionalism, competence, knowledge of financial management and intensity guidance apparatus Inspectorate together to the quality of the financial statements of Regions; 2. Examine the effect of professionalism partially on the quality of the financial statements of Regions; 3. Test the effect of partial competencies to the quality of the financial statements of Regions; 4. Examine the effect of knowledge of financial management partially on the quality of the financial statements of Regions; 5. The authorities test the effects of intensity guidance apparatus partially on the quality of the financial statements of Regions. The object of this research is the Government Internal Supervisory Apparatus (APIP working in the Inspectorate districts/cities in Aceh amounted to 23 people who perform inspection tasks.  The source of data in this study uses primary data which is the result of the acquisition of questionnaires from survey respondent, while research data collection techniques are done with documentation techniques. The analytical method used is Multiple Linear Regression Analysis. The results showed that: 1. Professionalism, competence, knowledge of financial management and intensity guidance apparatus jointly affect the quality of financial reporting area. 2. Professionalism partially affects the quality of financial reporting area. 3. Competence partially affects the quality of financial reporting area. 4. Knowledge of financial management partially affects the quality of financial reporting area. 5. The intensity guidance apparatus partially affects the quality of financial reporting area.

  14. Measuring Integrated Socioemotional Guidance at School: Factor Structure and Reliability of the Socioemotional Guidance Questionnaire (SEG-Q)

    Science.gov (United States)

    Jacobs, Karen; Struyf, Elke

    2013-01-01

    Socioemotional guidance of students has recently become an integral part of education, however no instrument exists to measure integrated socioemotional guidance. This study therefore examines the factor structure and reliability of the Socioemotional Guidance Questionnaire. Psychometric properties of the Socioemotional Guidance Questionnaire and…

  15. The Rendezvous Technique for Common Bile Duct Stones: A Meta-Analysis.

    Science.gov (United States)

    Huang, Long; Yu, Qing-sheng; Zhang, Qi; Liu, Ju-da; Wang, Zhen

    2015-12-01

    This article aimed to clarify the effectiveness and the efficiency of the rendezvous technique for patients with common bile duct stones. Four databases were searched on associations with rendezvous treatment. Six randomized controlled trials were evaluated for their success rate, stone clearance, morbidity, mortality, conversions, hospital stay, operating time, and hospitalization charges. This meta-analysis suggested no significant difference between the rendezvous group and the sequence group in the success rate and the stone clearance, but showed significant differences in the morbidity [odds ratio (OR)=0.54; 95% confidence intervals (CI), 0.30, 0.96], conversions (OR=0.40; 95% CI, 0.16, 0.97), the length of hospital stay (OR=-1.97; 95% CI, -2.29, -1.66), and the operating time (OR=12.95; 95% CI, 7.66, 18.24). The rendezvous technique is as effective as sequential endoscopic management for patients with common bile duct stones in its success rate and stone clearance, but the former is preferred in terms of morbidity, hospital stay, and hospitalization charges.

  16. Rendezvous procedure for the treatment of bile leaks and injury following segmental hepatectomy.

    Science.gov (United States)

    Nasr, John Y; Hashash, Jana G; Orons, Philip; Marsh, Wallis; Slivka, Adam

    2013-05-01

    Endoscopic retrograde cholangiopancreatography is a minimally invasive procedure used for the evaluation and management of biliary injuries. At times, ERCP fails and percutaneous modalities may be required. Rendezvous procedures are combined endoscopic and percutaneous techniques that have been used to restore anatomic continuity and biliary drainage in cases where retrograde and/or transhepatic access alone has failed either due to anatomic variation or traumatic injury with biloma formation. To assess if the Rendezvous technique plays a role in establishing biliary continuity in patients with a bile leak after segmental hepatectomy. We herby present a series of 3 patients who had complex bile leaks after segmental liver resection and underwent a combined percutaneous and endoscopic Rendezvous procedure to establish biliary continuity. This technique was successful in restoring biliary continuity and avoiding hepaticojejunostomy in 2 of the 3 patients. The Rendezvous technique may play a role in establishing biliary continuity in patients with biliary leak secondary to hepatic surgery. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  17. [Ureteral realignment with the rendezvous procedure in complex ureteral injuries - aspects of technique and our experience].

    Science.gov (United States)

    Brandt, Alexander Sascha; von Rundstedt, F-C; Lazica, D A; Roth, S

    2010-07-01

    The rendezvous procedure for re-establishing ureteral continuity after complex ureteral injuries is introduced and we present our experience with this technique. Aspects of the technique are described in a detailed step-by-step instruction using intraoperative radiographs. We evaluated our patient data from 1998 until 2009 for cases in which the rendezvous procedure was attempted. The rendezvous procedure was used in a total of 11 patients. Realignment was successful in 10 cases (90.9 %) and the initial nephrostomy could be removed. In 3 of 7 cases postoperative removal of the JJ ureteric stent was successful. In 7 patients the final surgical ureter reconstruction was performed after a medium period of 7 months. 5 cases of ureteroneocystostomy and 2 cases of reconstruction of the ureter either with colon or ileum segments were accomplished. In 1 patient a permanent maintenance of the DJ ureteral stent was necessary. Ureteral realignment with the rendezvous procedure enables disposition of the ureteral stent in many cases, exclusively antegrade or retrograde procedures failed. By this means nephrostomy could be spared as a temporary or permanent solution and a better chance of restitutio ad integrum could be realised. Georg Thieme Verlag KG Stuttgart * New York.

  18. Optimal planning approaches with multiple impulses for rendezvous based on hybrid genetic algorithm and control method

    Directory of Open Access Journals (Sweden)

    JingRui Zhang

    2015-03-01

    Full Text Available In this article, we focus on safe and effective completion of a rendezvous and docking task by looking at planning approaches and control with fuel-optimal rendezvous for a target spacecraft running on a near-circular reference orbit. A variety of existent practical path constraints are considered, including the constraints of field of view, impulses, and passive safety. A rendezvous approach is calculated by using a hybrid genetic algorithm with those constraints. Furthermore, a control method of trajectory tracking is adopted to overcome the external disturbances. Based on Clohessy–Wiltshire equations, we first construct the mathematical model of optimal planning approaches of multiple impulses with path constraints. Second, we introduce the principle of hybrid genetic algorithm with both stronger global searching ability and local searching ability. We additionally explain the application of this algorithm in the problem of trajectory planning. Then, we give three-impulse simulation examples to acquire an optimal rendezvous trajectory with the path constraints presented in this article. The effectiveness and applicability of the tracking control method are verified with the optimal trajectory above as control objective through the numerical simulation.

  19. Lyapunov design of event-based controllers for the rendez-vous of coupled systems

    NARCIS (Netherlands)

    De Persis, Claudio; Postoyan, Romain

    2014-01-01

    The objective is to present a new type of triggering conditions together with new proof concepts for the event-based coordination of multi-agents. As a first step, we focus on the rendez-vous of two identical systems modeled as double integrators with additional damping in the velocity dynamics. The

  20. The Effect of Air Drag in Optimal Power-Limited Rendezvous Between Coplanar Low-Earth Orbits

    Directory of Open Access Journals (Sweden)

    Gil-Young Maeng

    1998-06-01

    Full Text Available The effect of air drag was researched when a low-earth orbit spacecraft using power-limited thruster rendezvoused another low-earth orbit spacecraft. The air density was assumed to decrease exponentially. The radius of parking orbit was 6655.935 km and that of target orbit was 7321.529 km. From the trajectories of active vehicles, the fuel consumption and the magnitude of thrust acceleration, we could conclude that the effect of air drag had to be considered in fuel optimal rendezvous problem between low-earth orbit spacecrafts. In multiple-revolution rendezvous case, the air drag was more effective.

  1. Guidance Counsellor Strategies for Handling Bullying

    Science.gov (United States)

    Power-Elliott, Michleen; Harris, Gregory E.

    2012-01-01

    The purpose of this exploratory-descriptive study was to examine how guidance counsellors in the province of Newfoundland and Labrador would handle a specific verbal-relational bullying incident. Also of interest was guidance counsellor involvement and training in bullying programmes and Positive Behaviour Supports. Data for this study was…

  2. Laparoendoscopic rendezvous in the treatment of cholecysto-choledocholitiasis: a single series of 200 patients.

    Science.gov (United States)

    La Barba, Giuliano; Gardini, Andrea; Cavargini, Elena; Casadei, Alessandro; Morgagni, Paolo; Bazzocchi, Francesca; D'Acapito, Fabrizio; Cavaliere, Davide; Curti, Roberta; Tringali, Domenico; Cucchetti, Alessandro; Ercolani, Giorgio

    2018-02-27

    Although the ideal management of cholecysto-choledocholitiasis is controversial, the two-stage approach, namely the common bile duct (CBD) clearance through endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy, remains the standard way of management. However, whenever feasible, the one-stage approach, using the so-called "laparoendoscopic rendezvous" (LERV) technique, offers some advantages, mainly reducing the hospital stay and the risk of post-ERCP pancreatitis. The aim of this study was to evaluate the safety and the efficacy of the one-stage approach, and to compare our results with data from available large studies. We reviewed our series of consecutive patients with cholecysto-choledocholitiasis treated by LERV from January 2003, to October 2016. Both elective and emergency cases were included. The primary end-point was the efficacy to obtain the CBD stones clearance. Secondary end-points were morbidity and mortality, operative time, conversion rate, and in-hospital stay. A total of 200 patients underwent a LERV procedure for the intra-operative diagnosis by intra-operative cholangiogram of cholecysto-choledocholitiasis. In 187 patients (93.5%), it was possible to cannulate the cystic duct with the jag-wire. Success rate was 95%. Conversion rate was 3%. The mean operative time was 135 min and the mean in-hospital stay was 4 days. 29 (14.5%) were the early complications, six mild pancreatitis. Four patients required re-operation during the hospital stay. 11 patients (5.5%) developed late complications during a median follow-up of 57.7 months. Our results confirm that LERV technique is a safe procedure with high success rates for the treatment of cholecysto-choledocholitiasis. The major advantages include the single-stage treatment, the shorter hospital stay, and the lower incidence of post-ERCP pancreatitis.

  3. Deliberating Tarceva: A case study of how British NHS managers decide whether to purchase a high-cost drug in the shadow of NICE guidance.

    Science.gov (United States)

    Hughes, David; Doheny, Shane

    2011-11-01

    This paper examines audio-recorded data from meetings in which NHS managers decide whether to fund high-cost drugs for individual patients. It investigates the work of a Welsh individual patient commissioning (IPC) panel responsible for sanctioning the purchase of 'un-commissioned' treatments for exceptional cases. The case study presented highlights the changing rationales used for approving or denying a cancer drug, Tarceva, during a period when NICE first suggested it was not cost effective, but then changed its position in a final technology appraisal recommending use when the cost did not exceed that of an alternative product. Our data show how decisions taken in the shadow of NICE guidance remain complex and subject to local discretion. Guidance that takes time to prepare, is released in stages, and relates to particular disease stages, must be interpreted in the context of particular cases. The case-based IPC panel discourse stands in tension with the standardised population-based recommendations in guidance. Panel members, who based their decisions on the central notions of 'efficacy' and 'exceptionality', often struggled to apply NICE information on cost-effectiveness to their deliberations on efficacy (clinical effectiveness). The case study suggests that the complex nature of decision making makes standardization of outcomes very difficult to achieve, so that local professional judgement is likely to remain central to health care rationing at this level. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Guidance strategies for a participatory ergonomic intervention to increase the use of ergonomic measures of workers in construction companies: a study design of a randomised trial

    Science.gov (United States)

    2014-01-01

    Background More than seven out of 10 Dutch construction workers describe their work as physically demanding. Ergonomic measures can be used to reduce these physically demanding work tasks. To increase the use of ergonomic measures, employers and workers have to get used to other working methods and to maintaining them. To facilitate this behavioural change, participatory ergonomics (PE) interventions could be useful. For this study a protocol of a PE intervention is adapted in such a way that the intervention can be performed by an ergonomics consultant through face-to-face contacts or email contacts. The objective of this study is to evaluate the effectiveness of the face-to-face guidance strategy and the e-guidance strategy on the primary outcome measure: use of ergonomic measures by individual construction workers, and on the secondary outcome measures: the work ability, physical functioning and limitations due to physical problems of individual workers. Methods/Design The present study is a randomised intervention trial of six months in 12 companies to establish the effects of a PE intervention guided by four face-to-face contacts (N = 6) or guided by 13 email contacts (N = 6) on the primary and secondary outcome measures at baseline and after six months. Construction companies are randomly assigned to one of the guidance strategies with the help of a computer generated randomisation table. In addition, a process evaluation for both strategies will be performed to determine reach, dose delivered, dose received, precision, competence, satisfaction and behavioural change to find possible barriers and facilitators for both strategies. A cost-benefit analysis will be performed to establish the financial consequences of both strategies. The present study is in accordance with the CONSORT statement. Discussion The outcome of this study will help to 1) evaluate the effect of both guidance strategies, and 2) find barriers to and facilitators of both guidance

  5. Guidance strategies for a participatory ergonomic intervention to increase the use of ergonomic measures of workers in construction companies: a study design of a randomised trial.

    Science.gov (United States)

    Visser, Steven; van der Molen, Henk F; Sluiter, Judith K; Frings-Dresen, Monique H W

    2014-04-17

    More than seven out of 10 Dutch construction workers describe their work as physically demanding. Ergonomic measures can be used to reduce these physically demanding work tasks. To increase the use of ergonomic measures, employers and workers have to get used to other working methods and to maintaining them. To facilitate this behavioural change, participatory ergonomics (PE) interventions could be useful. For this study a protocol of a PE intervention is adapted in such a way that the intervention can be performed by an ergonomics consultant through face-to-face contacts or email contacts. The objective of this study is to evaluate the effectiveness of the face-to-face guidance strategy and the e-guidance strategy on the primary outcome measure: use of ergonomic measures by individual construction workers, and on the secondary outcome measures: the work ability, physical functioning and limitations due to physical problems of individual workers. The present study is a randomised intervention trial of six months in 12 companies to establish the effects of a PE intervention guided by four face-to-face contacts (N = 6) or guided by 13 email contacts (N = 6) on the primary and secondary outcome measures at baseline and after six months. Construction companies are randomly assigned to one of the guidance strategies with the help of a computer generated randomisation table. In addition, a process evaluation for both strategies will be performed to determine reach, dose delivered, dose received, precision, competence, satisfaction and behavioural change to find possible barriers and facilitators for both strategies. A cost-benefit analysis will be performed to establish the financial consequences of both strategies. The present study is in accordance with the CONSORT statement. The outcome of this study will help to 1) evaluate the effect of both guidance strategies, and 2) find barriers to and facilitators of both guidance strategies. When these strategies are

  6. "Ultra-rapid" sequential treatment in cholecystocholedocholithiasis: alternative same-day approach to laparoendoscopic rendezvous.

    Science.gov (United States)

    Borreca, Dario; Bona, Alberto; Bellomo, Maria Paola; Borasi, Andrea; De Paolis, Paolo

    2015-12-01

    There is still no consensus about timing of laparoscopic cholecystectomy after endoscopic retrograde cholangiopancreatography in the treatment of cholecystocholedocholithiasis. The aim of our retrospective study is to analyze the optimal timing of surgical treatment in patients presenting concurrent choledocholithiasis, choosing to perform a sequential endoscopic plus surgical approach, introducing a same-day two-stage alternative. All cases of cholecystocholedocholithiasis occurred between January 2007 and December 2014 in "Gradenigo" Hospital (Turin-Italy) were reviewed. Patients were divided into three groups, based on the timing of cholecystectomy after endoscopic retrograde cholangiopancreatography, and compared. Out of 2233 cholecystectomies performed in the mentioned time interval, have been identified 93 patients that fulfill the selection criteria. 36 patients were treated with a same-day approach, while 29 within first 72 h and 28 with delayed surgery. The overall length of stay was significantly lower in patients that were treated with a same-day approach (4.7 days), compared with other groups (p = 0.001), while no significant differences were found in terms of length of surgical intervention, intraoperative complications and conversions to open procedure, postoperative stay, morbidity and mortality. Patients treated with delayed surgery had a 18 % recurrency rate of biliary events, with an odds ratio of 14.13 (p = 0.018). Same-day two-stage approach should be performed in suitable patients at the index admission, reducing overall risks, improving the patients' quality-of-life, preventing recurrency, leading to a significant cost abatement; furthermore, this approach allows same outcomes of laparoendoscopic rendezvous, avoiding technical and organizational troubles.

  7. Cost analysis of laparoendoscopic rendezvous versus preoperative ERCP and laparoscopic cholecystectomy in the management of cholecystocholedocholithiasis.

    Science.gov (United States)

    Garbarini, Aldo; Reggio, Dario; Arolfo, Simone; Bruno, Marco; Passera, Roberto; Catalano, Giorgia; Barletti, Claudio; Salizzoni, Mauro; Morino, Mario; Petruzzelli, Luca; Arezzo, Alberto

    2017-08-01

    Evidence from controlled trials and meta-analyses suggests that laparoendoscopic rendezvous (LERV) is preferable to sequential treatment in the management of common bile duct stones. With this retrospective analysis of a prospective database that included consecutive patients treated for cholecystocholedocholithiasis at our institution between January 2007 and July 2015, we compared LERV with sequential treatment. The primary endpoint was global cost, defined as the cost/patient/hospital stay, and the secondary end points were efficacy and morbidity. Fisher's exact test or Mann-Whitney test was used. Of a total of 249 consecutive patients, 143 underwent LERV (group A) and 106 a two-stage procedure (group B). Based on an average cost of €613 for 1 day of hospital stay in the General Surgery Department, the overall median cost of treatment was €6403 for group A and €8194 for group B (p < 0.001). Operative time was significantly shorter (p < 0.001), and length of hospital stay was significantly longer for group B (p < 0.001). No mortality in either group was observed. The postoperative complications rate was significantly higher in group B than in group A (24.5 vs. 10.5%; p = 0.003). No significant difference in the postoperative pancreatitis rate or the number of patients with increased serum amylase at 24 h was observed in either group. Our study suggests that LERV is preferable to sequential treatment not only in terms of less morbidity, but also of lower costs accrued by a shorter hospital stay. However, the longer operative time raises multiple organizational issues in the coordination of surgery and endoscopy services.

  8. Laparoendoscopic Rendezvous for Concomitant Cholecystocholedocholithiasis: A Successful Modality Even in the Most Difficult Presentations Including Pregnancy.

    Science.gov (United States)

    Shirah, Bader Hamza; Mikwar, Zaher Abdulaziz; Ahmad, Akram Neyaz; Dahlan, Yaser Mohammed

    2016-01-01

    Background . Laparoendoscopic rendezvous (LERV) technique is emerging as an attractive treatment option for concomitant cholecystocholedocholithiasis. In this paper, we report our experience in performing the LERV technique in patients with unusual presentations in terms of anatomical difficulty, pregnancy, multiple comorbid diseases, and postlaparotomy. We aim to highlight the effectiveness of the LERV technique in some clinical situations where conventional methods would fail or carry high risks in adequately managing concomitant cholecystocholedocholithiasis. Methods . Four patients diagnosed to have concomitant cholecystocholedocholithiasis with associated difficult presentation or comorbid diseases were treated using the LERV technique. One patient presented with difficult anatomy where ERCP failed at initial attempts. Another patient was pregnant (first trimester). A third patient had complex comorbid diseases (bronchial asthma, hypertension, congestive heart failure, and end-stage renal disease on regular hemodialysis). A fourth patient had previous laparotomy and sigmoidectomy for diverticular disease and had severe hospital phobia. Results . All patients tolerated the LERV technique very well; no intraoperative occurrence was reported. The mean operative time was 86.3 ± 17.2 minutes; mean time of the endoscopic part was 29.4 ± 3.57 minutes. The mean blood loss was 44.3 ± 18.2 mL (range 20-85). Residual stone, postoperative complications, postoperative morbidity, and postoperative mortality were 0 (0%). Postoperative short hospital stay was reported in all patients, average 3 days (range 2-4). Conclusion . LERV procedure is a safe and effective treatment option for the management of concomitant cholecystocholedocholithiasis, even in difficult situations where other methods would fail or carry high risks, or in patients presenting with severe comorbid diseases or pregnancy. This procedure may emerge as an attractive alternative option for high

  9. Laparoendoscopic Rendezvous for Concomitant Cholecystocholedocholithiasis: A Successful Modality Even in the Most Difficult Presentations Including Pregnancy

    Directory of Open Access Journals (Sweden)

    Bader Hamza Shirah

    2016-01-01

    Full Text Available Background. Laparoendoscopic rendezvous (LERV technique is emerging as an attractive treatment option for concomitant cholecystocholedocholithiasis. In this paper, we report our experience in performing the LERV technique in patients with unusual presentations in terms of anatomical difficulty, pregnancy, multiple comorbid diseases, and postlaparotomy. We aim to highlight the effectiveness of the LERV technique in some clinical situations where conventional methods would fail or carry high risks in adequately managing concomitant cholecystocholedocholithiasis. Methods. Four patients diagnosed to have concomitant cholecystocholedocholithiasis with associated difficult presentation or comorbid diseases were treated using the LERV technique. One patient presented with difficult anatomy where ERCP failed at initial attempts. Another patient was pregnant (first trimester. A third patient had complex comorbid diseases (bronchial asthma, hypertension, congestive heart failure, and end-stage renal disease on regular hemodialysis. A fourth patient had previous laparotomy and sigmoidectomy for diverticular disease and had severe hospital phobia. Results. All patients tolerated the LERV technique very well; no intraoperative occurrence was reported. The mean operative time was 86.3±17.2 minutes; mean time of the endoscopic part was 29.4±3.57 minutes. The mean blood loss was 44.3±18.2 mL (range 20–85. Residual stone, postoperative complications, postoperative morbidity, and postoperative mortality were 0 (0%. Postoperative short hospital stay was reported in all patients, average 3 days (range 2–4. Conclusion. LERV procedure is a safe and effective treatment option for the management of concomitant cholecystocholedocholithiasis, even in difficult situations where other methods would fail or carry high risks, or in patients presenting with severe comorbid diseases or pregnancy. This procedure may emerge as an attractive alternative option for high

  10. THE GHOST IN THE MACHINE? THE VALUE OF EXPERT ADVICE IN THE PRODUCTION OF EVIDENCE-BASED GUIDANCE: A MIXED METHODS STUDY OF THE NICE INTERVENTIONAL PROCEDURES PROGRAMME.

    Science.gov (United States)

    Oyebode, Oyinlola; Patrick, Hannah; Walker, Alexander; Campbell, Bruce; Powell, John

    2016-01-01

    The aim of this study was to determine the aspects of expert advice that decision makers find most useful in the development of evidence-based guidance and to identify the characteristics of experts providing the most useful advice. First, semi-structured interviews were conducted with seventeen members of the Interventional Procedures Advisory Committee of the UK's National Institute of Health and Care Excellence. Interviews examined the usefulness of expert advice during guidance development. Transcripts were analyzed inductively to identify themes. Second, data were extracted from 211 experts' questionnaires for forty-one consecutive procedures. Usefulness of advice was scored using an index developed through the qualitative work. Associations between usefulness score and characteristics of the expert advisor were investigated using univariate and multivariate analyses. Expert opinion was seen as a valued complement to empirical evidence, providing context and tacit knowledge unavailable in published literature, but helpful for interpreting it. Interviewees also valued advice on the training and experience required to perform a procedure, on patient selection criteria and the place of a procedure within a clinical management pathway. Limitations of bias in expert opinion were widely acknowledged and skepticism expressed regarding the anecdotal nature of advice on safety or efficacy outcomes. Quantitative analysis demonstrated that the most useful advice was given by clinical experts with direct personal experience of the procedure, particularly research experience. Evidence-based guidance production is often characterized as a rational, pipeline process. This ignores the valuable role that expert opinion plays in guidance development, complementing and supporting the interpretation of empirical data.

  11. Developing a workbook to support the contextualisation of global health systems guidance: a case study identifying steps and critical factors for success in this process at WHO.

    Science.gov (United States)

    Alvarez, Elizabeth; Lavis, John N; Brouwers, Melissa; Schwartz, Lisa

    2018-03-02

    Global guidance can help countries strengthen their health systems to deliver effective interventions to their populations. However, to have an impact, guidance needs to be contextualised or adapted to local settings; this process includes consideration of health system arrangements and political system factors. To date, methods to support contextualisation do not exist. In response, a workbook was designed to provide specific methods and strategies to enable the contextualisation of WHO's 'Optimizing health worker roles to improve maternal and newborn health' (OptimizeMNH) guidance at the national or subnational level. The objective of this study was to describe the process of developing the workbook and identify key steps of the development process, barriers that arose and facilitators that helped overcome some of these barriers. A qualitative single case study design was carried out. Interviews, documents and a reflexive journal were used. Constant comparison and an edit-style of organisation were used during data analysis to develop concepts, themes, subthemes and relationships among them. Thirteen interviews were conducted and 52 documents were reviewed. Three main steps were identified in the process of developing the workbook for health systems guidance contextualisation, namely (1) determining the need for and gaining approval to develop the workbook, (2) developing the workbook (taking on the task, creating the structure of the workbook, operationalising its components, undergoing approval processes and editing it), and (3) implementing the workbook both at the WHO level and at the national/subnational level. Five barriers and/or facilitators emerged relevant to each step, namely (1) having well-placed and credible champions, (2) creating and capitalising on opportunities, (3) finding the right language to engage various actors and obtain buy-in, (4) obtaining and maintaining meaningful buy-in, and (5) ensuring access to resources. Understanding the key

  12. Robust H(∞) control for spacecraft rendezvous with a noncooperative target.

    Science.gov (United States)

    Wu, Shu-Nan; Zhou, Wen-Ya; Tan, Shu-Jun; Wu, Guo-Qiang

    2013-01-01

    The robust H(∞) control for spacecraft rendezvous with a noncooperative target is addressed in this paper. The relative motion of chaser and noncooperative target is firstly modeled as the uncertain system, which contains uncertain orbit parameter and mass. Then the H(∞) performance and finite time performance are proposed, and a robust H(∞) controller is developed to drive the chaser to rendezvous with the non-cooperative target in the presence of control input saturation, measurement error, and thrust error. The linear matrix inequality technology is used to derive the sufficient condition of the proposed controller. An illustrative example is finally provided to demonstrate the effectiveness of the controller.

  13. Failed common bile duct cannulation during pregnancy: Rescue with endoscopic ultrasound guided rendezvous procedure.

    Science.gov (United States)

    Singla, Vikas; Arora, Anil; Tyagi, Pankaj; Sharma, Praveen; Bansal, Naresh; Kumar, Ashish

    2016-01-01

    Common bile duct (CBD) stones can lead to serious complications and require intervention with either endoscopic retrograde cholangiopancreatography (ERCP) or laparoscopic techniques for urgent relief. On an average 10%-20% of the patients with gall bladder stones can have associated CBD stones. CBD stones during pregnancy can be associated with hazardous complications for both the mother and the fetus. Failed cannulation while performing ERCP during pregnancy is a technically demanding situation, which requires immediate rescue with special techniques. Conventional rescue techniques may not be feasible and can be associated with hazardous consequences. Endoscopic ultrasound (EUS) guided rendezvous technique has now emerged as a safe alternative, and in one of our patients, this technique was successfully attempted. To the best of our knowledge, this is the first case report in the literature on EUS-guided rendezvous procedure during pregnancy.

  14. "Rendezvous technique" for intraluminal vacuum therapy of anastomotic leakage of the jejunum.

    Science.gov (United States)

    Krajinovic, K; Reimer, S; Kudlich, T; Germer, C T; Wiegering, A

    2016-12-01

    Anastomotic leakage (AL) is one of the most common and serious complications following visceral surgery. In recent years, endoluminal vacuum therapy has dramatically changed therapeutic options for AL, but its use has been limited to areas easily accessible by endoscope. We describe the first use of endoluminal vacuum therapy in the small intestine employing a combined surgical and endoscopic "rendezvous technique" in which the surgeon assists the endoscopic placement of an endoluminal vacuum therapy sponge in the jejunum by means of a pullback string. This technique led to a completely closed AL after 27 days and 7 changes of the endosponge. The combined surgical and endoscopic rendezvous technique can be useful in cases of otherwise difficult endosponge placement.

  15. Choledocholithiasis and endo-laparoscopic rendezvous. Analysis of 59 consecutive cases.

    Science.gov (United States)

    Del Rio, Paolo; Dell'Abate, Paolo; Labonia, Domenico; Negri, Marco; Sianesi, Nicoletta; Arcuri, Maria Francesca; Sianesi, Mario

    2011-01-01

    Choledocholithiasis is a real problem of major clinical importance. The incidence of cholelithiasis is 10-20%. We have examined 2907 patients treated with videolaparoscopic cholecystectomy (VLC) between January 2001 and September 2009. 214 cases (7.4%) were affected by choledocolithiasis; among these, 59 consecutive cases were treated by rendezvous, 151 cases by sequential treatment (ERCP-ES before VLC), 3 cases by extraction with Dormia's basket, and 1 case by ERCP-ES after VLC. The complications were one biliary fistula and three hemorrhages (one from the cystic artery, one from the hepatic area and one from trocar's site). The mean hospital stay was 1.38 +/- 0.83 days for the rendezvous group vs 4 53 +/- 0.74 days in the sequential treatment group (prendezvous procedure reduces hospital stay and has a greater compliance (only one treatment). We can use this option in the management of cases where preoperative ERCP-ES has failed.

  16. Moving without a purpose: an experimental study of swarm guidance in the Western honey bee, Apis mellifera.

    Science.gov (United States)

    Makinson, James C; Beekman, Madeleine

    2014-06-01

    During reproductive swarming, honey bee scouts perform two very important functions. Firstly, they find new nesting locations and return to the swarm cluster to communicate their discoveries. Secondly, once the swarm is ready to depart, informed scout bees act as guides, leading the swarm to its final destination. We have previously hypothesised that the two processes, selecting a new nest site and swarm guidance, are tightly linked in honey bees. When swarms can be laissez faire about where they nest, reaching directional consensus prior to lift off seems unnecessary. If, in contrast, it is essential that the swarm reaches a precise location, either directional consensus must be near unanimous prior to swarm departure or only a select subgroup of the scouts guide the swarm. Here, we tested experimentally whether directional consensus is necessary for the successful guidance of swarms of the Western honey bee Apis mellifera by forcing swarms into the air prior to the completion of the decision-making process. Our results show that swarms were unable to guide themselves prior to the swarm reaching the pre-flight buzzing phase of the decision-making process, even when directional consensus was high. We therefore suggest that not all scouts involved in the decision-making process attempt to guide the swarm. © 2014. Published by The Company of Biologists Ltd.

  17. A CASE STUDY DEMONSTRATING U.S. EPA GUIDANCE FOR EVALUATING LANDFILL GAS EMISSIONS FROM CLOSED OR ABANDONED FACILITIES--BUSH VALLEY LANDFILL, HARFORD COUNTY, MARYLAND

    Science.gov (United States)

    The purpose of the activities described in this document is to provide a demonstration of the procedures and methodologies described within the "Guidance for Evaluating Landfill Gas Emissions from Closed or Abandoned Facilities" (Guidance). This demonstration provides an example ...

  18. Radiation effects in the Si-PIN detector on the Near Earth Asteroid Rendezvous mission

    CERN Document Server

    Starr, R; Evans, L G; Floyd, S R; McClanahan, T P; Trombka, J I; Goldsten, J O; Maurer, R H; McNutt, R L; Roth, D R

    1999-01-01

    A Si-PIN photodiode is being used as a solar X-ray monitor on the X-ray/gamma-ray spectrometer experiment which is flying on the Near Earth Asteroid Rendezvous spacecraft. Since its launch in February 1996 this photodiode has experienced several brief failures. These anomalies and other performance characteristics will be described. Efforts to reproduce these failures in ground tests with flight spare equipment will also be discussed.

  19. Image-guided ureteral reconstruction using rendezvous technique for complex ureteric transection after gunshot injuries.

    Science.gov (United States)

    Arabi, Mohammad; Mat'hami, Abdulaziz; Said, Mohammad T; Bulbul, Muhammad; Haddad, Maurice; Al-Kutoubi, Aghiad

    2016-01-01

    Management of complex ureteric transection poses a significant clinical challenge, particularly after gunshot injuries due to marked distortion of anatomy and associated tissue loss. We report two cases of total ureteric transection due to gunshot injury successfully repaired using fluoroscopy-guided rendezvous procedure and double J stent placement. This minimally invasive approach may offer a safe and effective technique to repair complete ureteral transection and obviate the need for complex surgical procedures.

  20. Analysis for orbital rendezvous of Chang'E-5 using SBI technique

    Science.gov (United States)

    Huang, Y.; Shan, Q.; Li, P.

    2016-12-01

    Chang'E-5 will be launched in later 2017/early 2018 using a new generation rocket from Wenchang satellite launch center, Hainan, China. It is a lunar sampling return mission, and it is the first time for China to carry out orbital rendezvous and docking in the Moon. How to achieve orbital rendezvous successfully in the Moon is very important in Chang'E-5 mission. Orbital rendezvous will be implemented between an orbiter and an ascender 200 km above the Moon. The ground tracking techniques include range, Doppler and VLBI, and they will be used to track the orbiter and the ascender when the ascender is about 70 km farther away from the orbiter. Later the ascender will approach the orbiter automatically. As a successful example, in Chang'E-3, the differential phase delay (delta delay) data between the rover and the lander are obtained with a random error of about 1 ps, and the relative position of the rover is determined with an accuracy of several meters by using same beam VLBI (SBI) technique. Here the application of the SBI technique for Chang'E-5 orbital rendezvous is discussed. SBI technique can be used to track the orbiter and the ascender simultaneously when they are in the same beam. Delta delay of the two probes can be derived, and the measurement accuracy is much higher than that of the traditional VLBI data because of the cancelation of common errors. Theoretically it can result in a more accurate relative orbit between the two probes. In the simulation, different strategies are discussed to analyze the contribution of SBI data to the orbit accuracy improvement especially relative orbit between the orbiter and ascender. The simulation results show that the relative position accuracy of the orbiter and ascender can reach about 1 m with delta delay data of 10 ps.

  1. Rendezvous Protocols and Dynamic Frequency Hopping Interference Design for Anti-Jamming Satellite Communication

    Science.gov (United States)

    2013-11-25

    previously considered this proactive approach to combat unintentional, persistent (non- reactive) interference . In this project, we plan on extending our...channel” (or code ) by chance, through public knowledge of the underlying protocol semantics , or by compromising one of the network devices. An alternative...AFRL-RV-PS- AFRL-RV-PS- TR-2013-0142 TR-2013-0142 RENDEZVOUS PROTOCOLS AND DYNAMIC FREQUENCY HOPPING INTERFERENCE DESIGN FOR ANTI-JAMMING

  2. A "rendezvous technique" for treating a pancreatic fistula after distal pancreatectomy.

    Science.gov (United States)

    Imai, Daisuke; Yamashita, Yo-ichi; Ikegami, Toru; Toshima, Takeo; Harimoto, Norifumi; Yoshizumi, Tomoharu; Soejima, Yuji; Shirabe, Ken; Ikeda, Tetsuo; Maehara, Yoshihiko

    2015-01-01

    Pancreatic fistulae are a major complication of distal pancreatectomy (DP). Some cases of severe pancreatic fistula require invasive procedures. There have been some reports concerning the effectiveness of pancreatic duct drainage through an endoscopic transpapillary approach for pancreatic fistulae. We herein present a case of a pancreatic fistula after DP that was successfully treated with percutaneous pancreatic duct drainage, which was performed using a combined percutaneous and endoscopic approach, named the "rendezvous technique". In our case, we performed distal pancreatectomy with celiac artery resection for a locally advanced pancreatic body cancer. On postoperative day (POD) 7, the drain amylase level increased up to 37,460 IU/l. Computed tomography (CT) revealed peripancreatic fluid collections. On POD 10, we placed a catheter in the main pancreatic duct using the rendezvous technique. CT on POD 14 revealed a decrease in the size of the peripancreatic fluid collection, and contrast imaging from the drains on POD 22 revealed almost complete disappearance of the fluid collection. We withdrew the pigtail catheter on POD 27 and the percutaneous pancreatic duct drain on POD 36. This patient was discharged from our hospital on POD 40. We herein report a new approach called the "rendezvous technique" for the management of pancreatic fistulae after DP that can be used instead of a stressful nasopancreatic tube.

  3. Imaging Flash Lidar for Safe Landing on Solar System Bodies and Spacecraft Rendezvous and Docking

    Science.gov (United States)

    Amzajerdian, Farzin; Roback, Vincent E.; Bulyshev, Alexander E.; Brewster, Paul F.; Carrion, William A; Pierrottet, Diego F.; Hines, Glenn D.; Petway, Larry B.; Barnes, Bruce W.; Noe, Anna M.

    2015-01-01

    NASA has been pursuing flash lidar technology for autonomous, safe landing on solar system bodies and for automated rendezvous and docking. During the final stages of the landing from about 1 kilometer to 500 meters above the ground, the flash lidar can generate 3-Dimensional images of the terrain to identify hazardous features such as craters, rocks, and steep slopes. The onboard flight computer can then use the 3-D map of terrain to guide the vehicle to a safe location. As an automated rendezvous and docking sensor, the flash lidar can provide relative range, velocity, and bearing from an approaching spacecraft to another spacecraft or a space station. NASA Langley Research Center has developed and demonstrated a flash lidar sensor system capable of generating 16,000 pixels range images with 7 centimeters precision, at 20 Hertz frame rate, from a maximum slant range of 1800 m from the target area. This paper describes the lidar instrument and presents the results of recent flight tests onboard a rocket-propelled free-flyer vehicle (Morpheus) built by NASA Johnson Space Center. The flights were conducted at a simulated lunar terrain site, consisting of realistic hazard features and designated landing areas, built at NASA Kennedy Space Center specifically for this demonstration test. This paper also provides an overview of the plan for continued advancement of the flash lidar technology aimed at enhancing its performance to meet both landing and automated rendezvous and docking applications.

  4. A Ground Testbed to Advance US Capability in Autonomous Rendezvous and Docking Project

    Science.gov (United States)

    D'Souza, Chris

    2014-01-01

    This project will advance the Autonomous Rendezvous and Docking (AR&D) GNC system by testing it on hardware, particularly in a flight processor, with a goal of testing it in IPAS with the Waypoint L2 AR&D scenario. The entire Agency supports development of a Commodity for Autonomous Rendezvous and Docking (CARD) as outlined in the Agency-wide Community of Practice whitepaper entitled: "A Strategy for the U.S. to Develop and Maintain a Mainstream Capability for Automated/Autonomous Rendezvous and Docking in Low Earth Orbit and Beyond". The whitepaper establishes that 1) the US is in a continual state of AR&D point-designs and therefore there is no US "off-the-shelf" AR&D capability in existence today, 2) the US has fallen behind our foreign counterparts particularly in the autonomy of AR&D systems, 3) development of an AR&D commodity is a national need that would benefit NASA, our commercial partners, and DoD, and 4) an initial estimate indicates that the development of a standardized AR&D capability could save the US approximately $60M for each AR&D project and cut each project's AR&D flight system implementation time in half.

  5. Trajectory design for a rendezvous mission to Earth's Trojan asteroid 2010 TK7

    Science.gov (United States)

    Lei, Hanlun; Xu, Bo; Zhang, Lei

    2017-12-01

    In this paper a rendezvous mission to the Earth's Trojan asteroid 2010 TK7 is proposed, and preliminary transfer trajectories are designed. Due to the high inclination (∼ 20.9°) of the target asteroid relative to the ecliptic plane, direct transfers usually require large amounts of fuel consumption, which is beyond the capacity of current technology. As gravity assist technique could effectively change the inclination of spacecraft's trajectory, it is adopted to reduce the launch energy and rendezvous velocity maneuver. In practical computation, impulsive and low-thrust, gravity-assisted trajectories are considered. Among all the trajectories computed, the low-thrust gravity-assisted trajectory with Venus-Earth-Venus (V-E-V) swingby sequence performs the best in terms of propellant mass. For a spacecraft with initial mass of 800 kg , propellant mass of the best trajectory is 36.74 kg . Numerical results indicate that both the impulsive and low-thrust, gravity-assisted trajectories corresponding to V-E-V sequence could satisfy mission constraints, and can be applied to practical rendezvous mission.

  6. Optimal Aerocapture Guidance

    Data.gov (United States)

    National Aeronautics and Space Administration — The main goal of my research is to develop, implement, verify, and validate an optimal numerical predictor-corrector aerocapture guidance algorithm that is...

  7. Coral Reef Guidance

    Science.gov (United States)

    Guidance prepared by EPA and Army Corps of Engineers concerning coral reef protection under the Clean Water Act, Marine Protection, Research, and Sanctuaries Act, Rivers and Harbors Act, and Federal Project Authorities.

  8. Laser Guidance Analysis Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility, which provides for real time, closed loop evaluation of semi-active laser guidance hardware, has and continues to be instrumental in the development...

  9. British Association for the Study of Community Dentistry (BASCD) guidance on sampling for surveys of child dental health. A BASCD coordinated dental epidemiology programme quality standard.

    Science.gov (United States)

    Pine, C M; Pitts, N B; Nugent, Z J

    1997-03-01

    The British Association for the Study of Community Dentistry (BASCD) is responsible for the coordination of locally based surveys of child dental health which permit local and national comparisons between health authorities and regions. These surveys began in 1985/86 in England and Wales, 1987/88 in Scotland and 1993/94 in Northern Ireland. BASCD has taken an increasing lead in setting quality standards in discussion with the NHS Epidemiology Coordinators of the Dental Epidemiology Programme. This paper comprises guidance on the sampling for these surveys.

  10. Effective communication of public health guidance to emergency department clinicians in the setting of emerging incidents: a qualitative study and framework.

    Science.gov (United States)

    Khan, Yasmin; Sanford, Sarah; Sider, Doug; Moore, Kieran; Garber, Gary; de Villa, Eileen; Schwartz, Brian

    2017-04-28

    Evidence to inform communication between emergency department clinicians and public health agencies is limited. In the context of diverse, emerging public health incidents, communication is urgent, as emergency department clinicians must implement recommendations to protect themselves and the public. The objectives of this study were to: explore current practices, barriers and facilitators at the local level for communicating public health guidance to emergency department clinicians in emerging public health incidents; and develop a framework that promotes effective communication of public health guidance to clinicians during emerging incidents. A qualitative study was conducted using semi-structured interviews with 26 key informants from emergency departments and public health agencies in Ontario, Canada. Data were analyzed inductively and the analytic approach was guided by concepts of complexity theory. Emergent themes corresponded to challenges and strategies for effective communication of public health guidance. Important challenges related to the coordination of communication across institutions and jurisdictions, and differences in work environments across sectors. Strategies for effective communication were identified as the development of partnerships and collaboration, attention to specific methods of communication used, and the importance of roles and relationship-building prior to an emerging public health incident. Following descriptive analysis, a framework was developed that consists of the following elements: 1) Anticipate; 2) Invest in building relationships and networks; 3) Establish liaison roles and redundancy; 4) Active communication; 5) Consider and respond to the target audience; 6) Leverage networks for coordination; and 7) Acknowledge and address uncertainty. The qualities inherent in local relationships cut across framework elements. This research indicates that relationships are central to effective communication between public health

  11. NGST fine guidance sensor

    Science.gov (United States)

    Rowlands, Neil; Hutchings, John; Murowinski, Richard G.; Alexander, Russ

    2003-03-01

    Instrumentation for the Next Generation Space Telescope (NGST) is currently in the Phase A definition stage. We have developed a concept for the NGST Fine Guidance Sensor or FGS. The FGS is a detector array based imager which resides in the NGST focal plane. We report here on tradeoff studies aimed at defining an overall configuration of the FGS which will meet the performance and interface requirements. A key performance requirement is a noise equivalent angle of 3 milli-arcseconds to be achieved with 95% probability for any pointing of the observatory in the celestial sphere. A key interface requirement is compatibility with the architecture of the Integrated Science Instrument Module (ISIM). The concept developed consists of two independent and redundant FGS modules, each with a 4' x 2' field of view covered by two 2048 x 2048 infrared detector arrays, providing 60 milli-arcsecond sampling. Performance modeling supporting the choice of this architecture and the trade space considered is presented. Each module has a set of readout electronics which perform star detection, pixel-by-pixel correction, and in fine guiding mode, centroid calculation. These readout electronics communicate with the ISIM Command &Data Handling Units where the FGS control software is based. Rationale for this choice of architecture is also presented.

  12. Single Balloon Enteroscopy-Assisted ERCP Using Rendezvous Technique for Sharp Angulation of Roux-en-Y Limb in a Patient with Bile Duct Stones

    Science.gov (United States)

    Itoi, Takao; Ishii, Kentaro; Sofuni, Atsushi; Itokawa, Fumihide; Kurihara, Toshio; Tsuchiya, Takayoshi; Tsuji, Shujiro; Umeda, Junko; Moriyasu, Fuminori

    2009-01-01

    The acute angulation of Roux-en-Y (R-Y) limb precludes endoscopic access for endoscopic retrograde cholangiopancreatography (ERCP) even using a balloon enteroscopy. Here, we describe a case of successful single balloon enteroscopy (SBE)-assisted ERCP using a rendezvous technique in a patient with sharply angulated R-Y limb in a 79-year-old woman who had bile duct stones. Method. At first, a guidewire was passed antegradely through the major papilla after the needle puncture using percutaneous transhepatic biliary drainage technique. A hydrophilic guidewire with an ERCP catheter was antegradely advanced beyond the Roux limb. After a guidewire was firmly grasped by a snare forceps, it was pulled out of the body, resulting that the enteroscope could advance to the papilla. After papillary dilation, complete removal of bile duct stones was achieved without any procedure-related complication. In conclusion, although further study is needed, SBE-assisted ERCP using a rendezvous technique may have a potential for selected patients. PMID:20169091

  13. Single Balloon Enteroscopy-Assisted ERCP Using Rendezvous Technique for Sharp Angulation of Roux-en-Y Limb in a Patient with Bile Duct Stones

    Directory of Open Access Journals (Sweden)

    Takao Itoi

    2009-01-01

    Full Text Available The acute angulation of Roux-en-Y (R-Y limb precludes endoscopic access for endoscopic retrograde cholangiopancreatography (ERCP even using a balloon enteroscopy. Here, we describe a case of successful single balloon enteroscopy (SBE-assisted ERCP using a rendezvous technique in a patient with sharply angulated R-Y limb in a 79-year-old woman who had bile duct stones. Method. At first, a guidewire was passed antegradely through the major papilla after the needle puncture using percutaneous transhepatic biliary drainage technique. A hydrophilic guidewire with an ERCP catheter was antegradely advanced beyond the Roux limb. After a guidewire was firmly grasped by a snare forceps, it was pulled out of the body, resulting that the enteroscope could advance to the papilla. After papillary dilation, complete removal of bile duct stones was achieved without any procedure-related complication. In conclusion, although further study is needed, SBE-assisted ERCP using a rendezvous technique may have a potential for selected patients.

  14. Building America Case Study: Design Guidance for Passive Vents in New Construction Multifamily Buildings, New York, New York

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    This document addresses the use of passive vents as a source of outdoor air in multifamily buildings. The challenges associated with implementing passive vents and the factors affecting performance are outlined. A comprehensive design methodology and quantified performance metrics are provided. Two hypothetical design examples are provided to illustrate the process. This document is intended to be useful to designers, decision-makers, and contractors implementing passive ventilation strategies. It is also intended to be a resource for those responsible for setting high-performance building program requirements, especially pertaining to ventilation and outdoor air. To ensure good indoor air quality, a dedicated source of outdoor air is an integral part of high-performance buildings. Presently, there is a lack of guidance pertaining to the design and installation of passive vents, resulting in poor system performance. This report details the criteria necessary for designing, constructing, and testing passive vent systems to enable them to provide consistent and reliable levels of ventilation air from outdoors.

  15. Guidance and control, 1993; Annual Rocky Mountain Guidance and Control Conference, 16th, Keystone, CO, Feb. 6-10, 1993

    Science.gov (United States)

    Culp, Robert D.; Bickley, George

    Papers from the sixteenth annual American Astronautical Society Rocky Mountain Guidance and Control Conference are presented. The topics covered include the following: advances in guidance, navigation, and control; control system videos; guidance, navigation and control embedded flight control systems; recent experiences; guidance and control storyboard displays; and applications of modern control, featuring the Hubble Space Telescope (HST) performance enhancement study. For individual titles, see A95-80390 through A95-80436.

  16. A Study on the International Tourism of Jiangxi Province under the Guidance of One Belt, One Road Strategy

    Directory of Open Access Journals (Sweden)

    Guo Xiaojing

    2016-07-01

    Full Text Available In recent years, with the shift and violent development of economic globalization and sciences and technology, the connection between counties and citizens all over the world has become more and more intimate, so that the international tourism develops quickly and has become one of the important revenue sources gradually. In 2013, China proposed the new strategic thought of One Belt, One Road (the Silk Road Economic Belt and 21st Century Maritime Silk Road. Jiangxi province will bring its local regional superiority to full play under the guidance of the strategic thought, and powerfully cooperate with neighboring provinces and cities, in order to actively participate in the international tourism market and attempt to make its international tourism bigger and stronger. As the national strategic pillar industry, tourism plays an important role in the regional industrial structure adjustment and upgrade. Possessing the characteristics of strong integration, high interactivity and wide expansibility, tourism is the important engine to accelerate the development of urban economy. In September and October of 2013,during the visit of Chinese President Xi Jinping to countries of Central and East Asia, he successively proposed the significant suggestions of the Silk Road Economic Belt and 21st Century Maritime Silk Road, and the two of them were collectively intituled as One Belt, One Road New Strategic Thought. Silk Road Economic Belt covers the integration of the Southeast and Northeast Asian Economy entities which were eventually merged to lead to Europe. 21st Century Maritime Silk Road refers to unite Europe, Asia and Africa at sea in order to form a complete economic belt. Based on the increasingly deepening of economic integration, One Belt, One Road New Strategy is an international strategy which possesses the strategic importance of promoting industry upgrading and accelerating the transformation of economic growth mode for the purpose of mutual

  17. Threshold guidance update

    International Nuclear Information System (INIS)

    Wickham, L.E.

    1986-01-01

    The Department of Energy (DOE) is developing the concept of threshold quantities for use in determining which waste materials must be handled as radioactive waste and which may be disposed of as nonradioactive waste at its sites. Waste above this concentration level would be managed as radioactive or mixed waste (if hazardous chemicals are present); waste below this level would be handled as sanitary waste. Last years' activities (1984) included the development of a threshold guidance dose, the development of threshold concentrations corresponding to the guidance dose, the development of supporting documentation, review by a technical peer review committee, and review by the DOE community. As a result of the comments, areas have been identified for more extensive analysis, including an alternative basis for selection of the guidance dose and the development of quality assurance guidelines. Development of quality assurance guidelines will provide a reasonable basis for determining that a given waste stream qualifies as a threshold waste stream and can then be the basis for a more extensive cost-benefit analysis. The threshold guidance and supporting documentation will be revised, based on the comments received. The revised documents will be provided to DOE by early November. DOE-HQ has indicated that the revised documents will be available for review by DOE field offices and their contractors

  18. Regulatory guidance document

    International Nuclear Information System (INIS)

    1994-05-01

    The Office of Civilian Radioactive Waste Management (OCRWM) Program Management System Manual requires preparation of the OCRWM Regulatory Guidance Document (RGD) that addresses licensing, environmental compliance, and safety and health compliance. The document provides: regulatory compliance policy; guidance to OCRWM organizational elements to ensure a consistent approach when complying with regulatory requirements; strategies to achieve policy objectives; organizational responsibilities for regulatory compliance; guidance with regard to Program compliance oversight; and guidance on the contents of a project-level Regulatory Compliance Plan. The scope of the RGD includes site suitability evaluation, licensing, environmental compliance, and safety and health compliance, in accordance with the direction provided by Section 4.6.3 of the PMS Manual. Site suitability evaluation and regulatory compliance during site characterization are significant activities, particularly with regard to the YW MSA. OCRWM's evaluation of whether the Yucca Mountain site is suitable for repository development must precede its submittal of a license application to the Nuclear Regulatory Commission (NRC). Accordingly, site suitability evaluation is discussed in Chapter 4, and the general statements of policy regarding site suitability evaluation are discussed in Section 2.1. Although much of the data and analyses may initially be similar, the licensing process is discussed separately in Chapter 5. Environmental compliance is discussed in Chapter 6. Safety and Health compliance is discussed in Chapter 7

  19. PIV Logon Configuration Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Glen Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-04

    This document details the configurations and enhancements implemented to support the usage of federal Personal Identity Verification (PIV) Card for logon on unclassified networks. The guidance is a reference implementation of the configurations and enhancements deployed at the Los Alamos National Laboratory (LANL) by Network and Infrastructure Engineering – Core Services (NIE-CS).

  20. Vocational guidance in social volunteering

    Directory of Open Access Journals (Sweden)

    Nikolay S. Pryazhnikov

    2017-03-01

    Full Text Available The paper discusses the possibilities and limitations of vocational guidance in the social volunteering system. The essence of volunteer work is closely related with assistance to desperate people in searching for the meaning of living, often coinciding with labour activity that are deemed in terms of “the main matter of life” and “the leading activity”. For adolescents, it is the choice of career, and for adults, it is the work proper (i.e. an essential condition for personal self-realization. The problem of “forced volunteering” for experts in vocational guidance also means that they often have to work voluntarily and unselfishly outside the official guidelines. To clarify the terms «volunteer» and «a person in desperate need of help» the study used the method of analyzing the documents, e.g. the Regulations on Social Volunteering, the generalization of psychological sources, the initial survey of university students as active supporters of the volunteer movement, On the essence of volunteering and the place of career guidance in selfless social work. Vocational guidance is not excluded from the general system of volunteerism, but has an insufficiently defined status and low popularity among participants in social volunteering. Also, the problem of «forced volunteering» of experts in career counseling, which often requires voluntary and unselfish performance of quality work outside the framework of official instructions, is also indicated. Simultaneously, positive aspects of such disinterested career initiatives are noted, in particular, less control by the official inspectors (or customers and, accordingly, greater freedom of creativity than when someone else does the work.

  1. Combined Surgical and Transhepatic Rendezvous Procedure for Relieving Anastomotic Biliary Obstruction in Children with Liver Transplants.

    Science.gov (United States)

    Crowley, John; Soltys, Kyle; Sindhi, Rakesh; Baskin, Kevin; Yilmaz, Sabri; Close, Orrie; Medsinge, Avinash

    2017-08-01

    Four children (3 boys and 1 girl, age 1.4-9.4 y) presented 2-70 months after liver transplantation (mean 26 months) with high-grade narrowing at the surgical anastomosis that could not be crossed at percutaneous transhepatic cholangiography. Each patient was treated with a combined surgical and interventional radiology "rendezvous" procedure. Biliary drainage catheters were left in place for an average of 6 months after the procedure. At a mean 7.5 months after biliary drainage catheter removal, all children were catheter-free without clinical or biochemical evidence of biliary stricture recurrence. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

  2. Sheath rendezvous method: a novel distal protection technique during endovascular treatment of subclavian artery occlusions.

    Science.gov (United States)

    Haraguchi, Takuya; Urasawa, Kazushi; Nakama, Tatsuya; Nakagawa, Yuya; Tan, Michinao; Koshida, Ryoji; Sato, Katsuhiko

    2016-10-01

    To describe an innovative distal protection technique, "sheath rendezvous method", during endovascular treatment for subclavian arterial occlusions. 4.5F and 6F guiding sheath were inserted from left brachial and common femoral artery, respectively. 0.014″ guidewire retrogradely passed through occlusion and into antegrade sheath to establish a pull-through system. 3.0 mm balloon was used to expand occlusion and anchor to deliver retrograde sheath into antegrade one. Both sheaths locked by balloon dilatation crossed occlusion until antegrade sheath passed over lesion. Balloon expandable stent was delivered within antegrade sheath. Sheath was removed, and stent was implanted. We obtained an excellent outcome without complications.

  3. System and Method for Automated Rendezvous, Docking and Capture of Autonomous Underwater Vehicles

    Science.gov (United States)

    Stone, William C. (Inventor); Clark, Evan (Inventor); Richmond, Kristof (Inventor); Paulus, Jeremy (Inventor); Kapit, Jason (Inventor); Scully, Mark (Inventor); Kimball, Peter (Inventor)

    2018-01-01

    A system for automated rendezvous, docking, and capture of autonomous underwater vehicles at the conclusion of a mission comprising of comprised of a docking rod having lighted, pulsating (in both frequency and light intensity) series of LED light strips thereon, with the LEDs at a known spacing, and the autonomous underwater vehicle specially designed to detect and capture the docking rod and then be lifted structurally by a spherical end strop about which the vehicle can be pivoted and hoisted up (e.g., onto a ship). The method of recovery allows for very routine and reliable automated recovery of an unmanned underwater asset.

  4. Robust control for spacecraft rendezvous system with actuator unsymmetrical saturation: a gain scheduling approach

    Science.gov (United States)

    Wang, Qian; Xue, Anke

    2018-06-01

    This paper has proposed a robust control for the spacecraft rendezvous system by considering the parameter uncertainties and actuator unsymmetrical saturation based on the discrete gain scheduling approach. By changing of variables, we transform the actuator unsymmetrical saturation control problem into a symmetrical one. The main advantage of the proposed method is improving the dynamic performance of the closed-loop system with a region of attraction as large as possible. By the Lyapunov approach and the scheduling technology, the existence conditions for the admissible controller are formulated in the form of linear matrix inequalities. The numerical simulation illustrates the effectiveness of the proposed method.

  5. BENCHPAR PROJECT. How to Incorporate ThermaI-Hydro-Mechanical Coupled Processes into Performance Assessments and Design Studies for Radioactive Waste Disposal in Geological Formations. Guidance Document

    International Nuclear Information System (INIS)

    Stephansson, O.; Andersson, Johan

    2005-02-01

    The objective of this Guidance Document is to provide advice on how to incorporate thermo-hydro-mechanical (THM) coupled processes into Performance Assessments (PAS) and design studies for radioactive waste disposal in geological formations to be experienced in a European context. The document has been generated by the EU research project BENCHPAR: Benchmark Tests and Guidance on Coupled Processes for Performance Assessment of Nuclear Waste Repositories. The document starts in Section 1 with an explanation of why numerical analyses incorporating THM mechanisms are required for radioactive waste studies and provides background material on the subject. Then, the THM processes and their interactions are explained in Section 2. Three case examples of THM numerical analysis are presented in Section 3 to illustrate the type of work that can be conducted to study the near-field, upscaling, and the far-field. For the three cases, there is discussion on the main findings, the relevance to a safety case, the relative importance of the different couplings, and the uncertainties involved. The importance and priority of the THM couplings are then summarized in Section 4. It is especially important to be able to technically audit the numerical analyses in order to establish that all the relevant variables, parameters and mechanisms have been included in the modelling and hence that the numerical model adequately represents the rock and engineering reality. Accordingly, recommended soft and hard auditing procedures are presented in Section 5. In this Guidance Document, we emphasize especially that the most important step in numerical modelling is not executing the calculations per se, but the earlier conceptualization of the problem regarding the dominant processes, the material properties and parameters, the engineering perturbations, and their mathematical presentations. The associated modelling component of addressing the uncertainties and estimating their influence on the

  6. Rendezvous with IQ: Metacognition in Real-Life Situations

    Science.gov (United States)

    Al-Hilawani, Yasser A.

    2018-01-01

    The purpose of this study was to examine the relationship between metacognition as measured in real-life situations and IQ scores as reflected by performance on the Raven Standard Progressive Matrices Scale. It is also intended in this study to report on whether or not there were significant differences in performance on the metacognitive…

  7. A manned maneuvering unit proximity operations planning and flight guidance display and control system

    Science.gov (United States)

    Gershzohn, Gary R.; Sirko, Robert J.; Zimmerman, K.; Jones, A. D.

    1990-01-01

    This task concerns the design, development, testing, and evaluation of a new proximity operations planning and flight guidance display and control system for manned space operations. A forecast, derivative manned maneuvering unit (MMU) was identified as a candidate for the application of a color, highway-in-the-sky display format for the presentation of flight guidance information. A silicon graphics 4D/20-based simulation is being developed to design and test display formats and operations concepts. The simulation includes the following: (1) real-time color graphics generation to provide realistic, dynamic flight guidance displays and control characteristics; (2) real-time graphics generation of spacecraft trajectories; (3) MMU flight dynamics and control characteristics; (4) control algorithms for rotational and translational hand controllers; (5) orbital mechanics effects for rendezvous and chase spacecraft; (6) inclusion of appropriate navigation aids; and (7) measurement of subject performance. The flight planning system under development provides for: (1) selection of appropriate operational modes, including minimum cost, optimum cost, minimum time, and specified ETA; (2) automatic calculation of rendezvous trajectories, en route times, and fuel requirements; (3) and provisions for manual override. Man/machine function allocations in planning and en route flight segments are being evaluated. Planning and en route data are presented on one screen composed of two windows: (1) a map display presenting a view perpendicular to the orbital plane, depicting flight planning trajectory and time data attitude display presenting attitude and course data for use en route; and (2) an attitude display presenting local vertical-local horizontal attitude data superimposed on a highway-in-the-sky or flight channel representation of the flight planned course. Both display formats are presented while the MMU is en route. In addition to these displays, several original display

  8. Endoscopic Ultrasound-guided Rendezvous Technique after Failed Endoscopic Retrograde Cholangiopancreatography: Which Approach Route Is the Best?

    Science.gov (United States)

    Okuno, Nozomi; Hara, Kazuo; Mizuno, Nobumasa; Hijioka, Susumu; Tajika, Masahiro; Tanaka, Tsutomu; Ishihara, Makoto; Hirayama, Yutaka; Onishi, Sachiyo; Niwa, Yasumasa; Yamao, Kenji

    2017-12-01

    Objective The endoscopic ultrasound-guided rendezvous technique (EUS-RV) is a salvage method for failed selective biliary cannulation. Three puncture routes have been reported, with many comparisons between the intra-hepatic and extra-hepatic biliary ducts. We used the trans-esophagus (TE) and trans-jejunum (TJ) routes. In the present study, the utility of EUS-RV for biliary access was evaluated, focusing on the approach routes. Methods and Patients In 39 patients, 42 puncture routes were evaluated in detail. EUS-RV was performed between January 2010 and December 2014. The patients were prospectively enrolled, and their clinical data were retrospectively collected. Results The patients' median age was 71 (range 29-84) years. The indications for endoscopic retrograde cholangiopancreatography (ERCP) were malignant biliary obstruction in 24 patients and benign biliary disease in 15. The technical success rate was 78.6% (33/42) and was similar among approach routes (p=0.377). The overall complication rate was 16.7% (7/42) and was similar among approach routes (p=0.489). However, mediastinal emphysema occurred in 2 TE route EUS-RV patients. No EUS-RV-related deaths occurred. Conclusion EUS-RV proved reliable after failed ERCP. The selection of the appropriate route based on the patient's condition is crucial.

  9. Endoscopic Ultrasound Guided Rendezvous Drainage of Biliary Obstruction Using a New Flexible 19-Gauge Fine Needle Aspiration Needle.

    Science.gov (United States)

    Tang, Zhouwen; Igbinomwanhia, Efehi; Elhanafi, Sherif; Othman, Mohamed O

    2016-01-01

    Background and Aim. A successful endoscopic ultrasound guided rendezvous (EUS-RV) biliary drainage is dependent on accurate puncture of the bile duct and precise guide wire manipulation across the ampulla of Vater. We aim to study the feasibility of using a flexible 19-gauge fine aspiration needle in the performance of EUS-RV biliary drainage. Method. This is a retrospective case series of EUS-RV biliary drainage procedures at a single center. Patients who failed ERCP during the same session for benign or malignant biliary obstruction underwent EUS-RV using a flexible, nitinol covered, 19-gauge needle for biliary access and guide wire manipulation. Result. 24 patients underwent EUS-RV biliary drainage via extrahepatic access while 1 attempt was via intrahepatic access. The technical success rate was 80%, including 83.3% of cases via extrahepatic access. There was no significant difference in success rate of inpatient and outpatient procedures, benign or malignant indications, or type of guide wire used. Adverse events included mild pancreatitis (3 patients) and cholangitis (1 patient). Conclusion. A flexible 19-gauge needle for biliary access can be safe and effective when used to perform EUS-RV biliary drainage. Direct comparison between the nitinol needle and conventional metal needles in the performance of EUS guided biliary drainage is needed.

  10. A novel "hitch-and-ride" deep biliary cannulation method during rendezvous endoscopic ultrasound-guided ERCP technique.

    Science.gov (United States)

    Nakai, Yousuke; Isayama, Hiroyuki; Matsubara, Saburo; Kogure, Hirofumi; Mizuno, Suguru; Hamada, Tsuyoshi; Takahara, Naminatsu; Nakamura, Tomoka; Sato, Tatsuya; Takeda, Tsuyoshi; Hakuta, Ryunosuke; Ishigaki, Kazunaga; Saito, Kei; Tada, Minoru; Koike, Kazuhiko

    2017-10-01

    Background and study aim Endoscopic ultrasound-guided rendezvous (EUS-RV) is increasingly reported as a treatment option after failed endoscopic retrograde cholangiopancreatography. We developed a novel "hitch-and-ride" catheter for biliary cannulation to reduce the risk of guidewire loss during EUS-RV. Patients and methods We retrospectively evaluated safety and technical success of EUS-RV between June 2011 and May 2016. Biliary cannulation during EUS-RV using three methods - over-the-wire, along-the-wire, and hitch-and-ride - were compared. Results A total of 30 EUS-RVs were attempted and the technical success rate was 93.3 %, with two failures (one bile duct puncture and one guidewire insertion). After 28 cases of successful guidewire passage, cannulation was attempted by the over-the-wire (n = 13), along-the-wire (n = 4) or hitch-and-ride (n = 11) method. Only the hitch-and-ride method achieved biliary cannulation without guidewire loss or conversion to the other methods. Time to cannulation was shorter with the hitch-and-ride method (4 minutes) than with over-the-wire and along-the-wire methods (9 and 13 minutes, respectively). The adverse event rate of EUS-RV was 23.3 %. Conclusion A novel hitch-and-ride catheter was feasible for biliary cannulation after EUS-RV. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Laparoendoscopic rendezvous may be an effective alternative to a failed preoperative endoscopic retrograde cholangiopancreatography in patients with cholecystocholedocholithiasis.

    Science.gov (United States)

    Tsiopoulos, Fotios; Kapsoritakis, Andreas; Psychos, Athanassios; Manolakis, Anastasios; Oikonomou, Konstantinos; Tzovaras, George; Baloyiannis, Ioannis; Tsikrika, Alexandra; Potamianos, Spyros

    2018-01-01

    Endoscopic retrograde cholangiopancreatography (ERCP), followed by laparoscopic cholecystectomy (LC), remains the standard way of management for patients with cholecystocholedocholithiasis. Laparoendoscopic rendezvous (LERV), a combined procedure for removing the gallbladder laparoscopically and clearing the common bile duct (CBD) endoscopically at the same time, could be an attractive alternative. The aim of this study was to compare LERV with classic ERCP in patients with cholecystocholedocholithiasis. 886 patients with cholecystocholedocholithiasis were treated either with the LERV technique (90 patients), or with the 2-stage approach, which includes preoperative ERCP followed by LC (796 patients). The primary endpoint was any difference in the success of CBD cannulation and clearance; secondary endpoints were the detection of differences in morbidity (especially post-ERCP pancreatitis [PEP]), and the feasibility of the two approaches. Successful cannulation of the CBD was more frequent with conventional ERCP compared with the LERV technique (89.8% vs. 75.5%, P=0.0001). LERV appears to be as effective as conventional ERCP for complete CBD clearance (85.5% vs. 82.8%, P<0.1). None of the patients in the LERV group had an episode of clinical PEP, whereas in the conventional ERCP group there were 23 episodes of PEP and one death. The median amylase level was higher in patients undergoing conventional ERCP group compared to patients in LERV group. Classic ERCP has a higher rate of successful CBD cannulation and a similar rate of CBD clearance compared to LERV.

  12. A New Path-Constrained Rendezvous Planning Approach for Large-Scale Event-Driven Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ahmadreza Vajdi

    2018-05-01

    Full Text Available We study the problem of employing a mobile-sink into a large-scale Event-Driven Wireless Sensor Networks (EWSNs for the purpose of data harvesting from sensor-nodes. Generally, this employment improves the main weakness of WSNs that is about energy-consumption in battery-driven sensor-nodes. The main motivation of our work is to address challenges which are related to a network’s topology by adopting a mobile-sink that moves in a predefined trajectory in the environment. Since, in this fashion, it is not possible to gather data from sensor-nodes individually, we adopt the approach of defining some of the sensor-nodes as Rendezvous Points (RPs in the network. We argue that RP-planning in this case is a tradeoff between minimizing the number of RPs while decreasing the number of hops for a sensor-node that needs data transformation to the related RP which leads to minimizing average energy consumption in the network. We address the problem by formulating the challenges and expectations as a Mixed Integer Linear Programming (MILP. Henceforth, by proving the NP-hardness of the problem, we propose three effective and distributed heuristics for RP-planning, identifying sojourn locations, and constructing routing trees. Finally, experimental results prove the effectiveness of our approach.

  13. A New Path-Constrained Rendezvous Planning Approach for Large-Scale Event-Driven Wireless Sensor Networks.

    Science.gov (United States)

    Vajdi, Ahmadreza; Zhang, Gongxuan; Zhou, Junlong; Wei, Tongquan; Wang, Yongli; Wang, Tianshu

    2018-05-04

    We study the problem of employing a mobile-sink into a large-scale Event-Driven Wireless Sensor Networks (EWSNs) for the purpose of data harvesting from sensor-nodes. Generally, this employment improves the main weakness of WSNs that is about energy-consumption in battery-driven sensor-nodes. The main motivation of our work is to address challenges which are related to a network’s topology by adopting a mobile-sink that moves in a predefined trajectory in the environment. Since, in this fashion, it is not possible to gather data from sensor-nodes individually, we adopt the approach of defining some of the sensor-nodes as Rendezvous Points (RPs) in the network. We argue that RP-planning in this case is a tradeoff between minimizing the number of RPs while decreasing the number of hops for a sensor-node that needs data transformation to the related RP which leads to minimizing average energy consumption in the network. We address the problem by formulating the challenges and expectations as a Mixed Integer Linear Programming (MILP). Henceforth, by proving the NP-hardness of the problem, we propose three effective and distributed heuristics for RP-planning, identifying sojourn locations, and constructing routing trees. Finally, experimental results prove the effectiveness of our approach.

  14. A New Path-Constrained Rendezvous Planning Approach for Large-Scale Event-Driven Wireless Sensor Networks

    Science.gov (United States)

    Zhang, Gongxuan; Wang, Yongli; Wang, Tianshu

    2018-01-01

    We study the problem of employing a mobile-sink into a large-scale Event-Driven Wireless Sensor Networks (EWSNs) for the purpose of data harvesting from sensor-nodes. Generally, this employment improves the main weakness of WSNs that is about energy-consumption in battery-driven sensor-nodes. The main motivation of our work is to address challenges which are related to a network’s topology by adopting a mobile-sink that moves in a predefined trajectory in the environment. Since, in this fashion, it is not possible to gather data from sensor-nodes individually, we adopt the approach of defining some of the sensor-nodes as Rendezvous Points (RPs) in the network. We argue that RP-planning in this case is a tradeoff between minimizing the number of RPs while decreasing the number of hops for a sensor-node that needs data transformation to the related RP which leads to minimizing average energy consumption in the network. We address the problem by formulating the challenges and expectations as a Mixed Integer Linear Programming (MILP). Henceforth, by proving the NP-hardness of the problem, we propose three effective and distributed heuristics for RP-planning, identifying sojourn locations, and constructing routing trees. Finally, experimental results prove the effectiveness of our approach. PMID:29734718

  15. Rendezvous with the World: Missouri Southern State University's Themed Semesters

    Science.gov (United States)

    Stebbins, Chad

    2011-01-01

    Although most universities emphasize study abroad as the primary vehicle to internationalize the campus, in reality only a small percentage of students actually participate in this endeavor. The internationally themed semesters at Missouri Southern State University (MSSU) reach virtually every student, and provide a global perspective and cultural…

  16. Endoscopic Sphincterotomy Using the Rendezvous Technique for Choledocholithiasis during Laparoscopic Cholecystectomy: A Case Report.

    Science.gov (United States)

    Tanaka, Takayuki; Haraguchi, Masashi; Tokai, Hirotaka; Ito, Shinichiro; Kitajima, Masachika; Ohno, Tsuyoshi; Onizuka, Shinya; Inoue, Keiji; Motoyoshi, Yasuhide; Kuroki, Tamotsu; Kanemastu, Takashi; Eguchi, Susumu

    2014-05-01

    A 50-year-old male was examined at another hospital for fever, general fatigue and slight abdominal pain. He was treated with antibiotics and observed. However, his symptoms did not lessen, and laboratory tests revealed liver dysfunction, jaundice and an increased inflammatory response. He was then admitted to our hospital and underwent an abdominal computed tomography scan and magnetic resonance cholangiopancreatography (MRCP), which revealed common bile duct (CBD) stones. He was diagnosed with mild acute cholangitis. As the same time, he was admitted to our hospital and an emergency endoscopic retrograde cholangiopancreatography was performed. Vater papilla opening in the third portion of the duodenum and presence of a peripapillary duodenal diverticulum made it difficult to perform cannulation of the CBD. In addition, MRCP revealed that the CBD was extremely narrow (diameter 5 mm). We therefore performed laparoscopic cholecystectomy and endoscopic sphincterotomy using the rendezvous technique for choledocholithiasis simultaneously rather than laparoscopic CBD exploration. After the operation, the patient was discharged with no complications. Although the rendezvous technique has not been very commonly used because several experts in the technique and a large operating room are required, this technique is a very attractive and effective approach for treating choledocholithiasis, for which endoscopic treatment is difficult.

  17. Pancreatic duct drainage using EUS-guided rendezvous technique for stenotic pancreaticojejunostomy.

    Science.gov (United States)

    Takikawa, Tetsuya; Kanno, Atsushi; Masamune, Atsushi; Hamada, Shin; Nakano, Eriko; Miura, Shin; Ariga, Hiroyuki; Unno, Jun; Kume, Kiyoshi; Kikuta, Kazuhiro; Hirota, Morihisa; Yoshida, Hiroshi; Katayose, Yu; Unno, Michiaki; Shimosegawa, Tooru

    2013-08-21

    The patient was a 30-year-old female who had undergone excision of the extrahepatic bile duct and Roux-en-Y hepaticojejunostomy for congenital biliary dilatation at the age of 7. Thereafter, she suffered from recurrent acute pancreatitis due to pancreaticobiliary maljunction and received subtotal stomach-preserving pancreaticoduodenectomy. She developed a pancreatic fistula and an intra-abdominal abscess after the operation. These complications were improved by percutaneous abscess drainage and antibiotic therapy. However, upper abdominal discomfort and the elevation of serum pancreatic enzymes persisted due to stenosis from the pancreaticojejunostomy. Because we could not accomplish dilation of the stenosis by endoscopic retrograde cholangiopancreatography, we tried an endoscopic ultrasonography (EUS) guided rendezvous technique for pancreatic duct drainage. After transgastric puncture of the pancreatic duct using an EUS-fine needle aspiration needle, the guidewire was inserted into the pancreatic duct and finally reached to the jejunum through the stenotic anastomosis. We changed the echoendoscope to an oblique-viewing endoscope, then grasped the guidewire and withdrew it through the scope. The stenosis of the pancreaticojejunostomy was dilated up to 4 mm, and a pancreatic stent was put in place. Though the pancreatic stent was removed after three months, the patient remained symptom-free. Pancreatic duct drainage using an EUS-guided rendezvous technique was useful for the treatment of a stenotic pancreaticojejunostomy after pancreaticoduodenectomy.

  18. Endoscopic Sphincterotomy Using the Rendezvous Technique for Choledocholithiasis during Laparoscopic Cholecystectomy: A Case Report

    Directory of Open Access Journals (Sweden)

    Takayuki Tanaka

    2014-08-01

    Full Text Available A 50-year-old male was examined at another hospital for fever, general fatigue and slight abdominal pain. He was treated with antibiotics and observed. However, his symptoms did not lessen, and laboratory tests revealed liver dysfunction, jaundice and an increased inflammatory response. He was then admitted to our hospital and underwent an abdominal computed tomography scan and magnetic resonance cholangiopancreatography (MRCP, which revealed common bile duct (CBD stones. He was diagnosed with mild acute cholangitis. As the same time, he was admitted to our hospital and an emergency endoscopic retrograde cholangiopancreatography was performed. Vater papilla opening in the third portion of the duodenum and presence of a peripapillary duodenal diverticulum made it difficult to perform cannulation of the CBD. In addition, MRCP revealed that the CBD was extremely narrow (diameter 5 mm. We therefore performed laparoscopic cholecystectomy and endoscopic sphincterotomy using the rendezvous technique for choledocholithiasis simultaneously rather than laparoscopic CBD exploration. After the operation, the patient was discharged with no complications. Although the rendezvous technique has not been very commonly used because several experts in the technique and a large operating room are required, this technique is a very attractive and effective approach for treating choledocholithiasis, for which endoscopic treatment is difficult.

  19. Environmental guidance regulatory bulletin

    International Nuclear Information System (INIS)

    1997-01-01

    This document describes the background on expanding public participation in the Resource Conservation and Recovery Act and DOE's response. The bulletin also describes the changes made by the final rule to existing regulations, guidance provided by EPA in the preamble and in the revised RCRA Public Participation Manual, the relationship between public participation and environmental justice, and DOE's recent public participation and environmental justice initiatives

  20. Theoretical and hands-on guidance from dental hygienists promotes good oral health in elderly people living in nursing homes, a pilot study.

    Science.gov (United States)

    Seleskog, B; Lindqvist, L; Wårdh, I; Engström, A; von Bültzingslöwen, I

    2018-04-12

    Oral health in nursing homes for elderly is often unsatisfactory, and oral health education to nursing staff has not shown sufficient results why there is need for novel approaches. The aim of the study was to trial a new oral healthcare educational programme and to evaluate the effects on residents' oral health. In addition, attitudes among the nursing staff in the intervention nursing home were explored. In a controlled clinical trial, two comparable nursing homes were randomly assigned for intervention or control. Interventions included weekly theoretical and hands-on guidance from dental hygienists on oral hygiene procedures and discussions on oral care routines. The residents' oral health, measured by the Revised Oral Assessment Guide (ROAG), dental plaque and gingival bleeding were evaluated at baseline and after 3 months. Attitudes among the staff to oral health care were measured at the intervention nursing home. Revised Oral Assessment Guide gums and lips scores showed a tendency to decrease in the intervention group, but remained high in the control group. Plaque levels improved significantly after intervention, and a trend towards less gingival bleeding was observed. The intervention nursing staff seemed to be more aware of their own limitations concerning oral health care after intervention and valued more frequent contact with dental services to a greater extent. The oral healthcare situation for elderly people today is so complex that theoretical education at the group level regarding different aspects of oral health is not sufficient. Individual hands-on guidance by dental hygienists on a regular basis in everyday care may be a new approach. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Q-Learning and p-persistent CSMA based rendezvous protocol for cognitive radio networks operating with shared spectrum activity

    Science.gov (United States)

    Watson, Clifton L.; Biswas, Subir

    2014-06-01

    With an increasing demand for spectrum, dynamic spectrum access (DSA) has been proposed as viable means for providing the flexibility and greater access to spectrum necessary to meet this demand. Within the DSA concept, unlicensed secondary users temporarily "borrow" or access licensed spectrum, while respecting the licensed primary user's rights to that spectrum. As key enablers for DSA, cognitive radios (CRs) are based on software-defined radios which allow them to sense, learn, and adapt to the spectrum environment. These radios can operate independently and rapidly switch channels. Thus, the initial setup and maintenance of cognitive radio networks are dependent upon the ability of CR nodes to find each other, in a process known as rendezvous, and create a link on a common channel for the exchange of data and control information. In this paper, we propose a novel rendezvous protocol, known as QLP, which is based on Q-learning and the p-persistent CSMA protocol. With the QLP protocol, CR nodes learn which channels are best for rendezvous and thus adapt their behavior to visit those channels more frequently. We demonstrate through simulation that the QLP protocol provides a rendevous capability for DSA environments with different dynamics of PU activity, while attempting to achieve the following performance goals: (1) minimize the average time-to-rendezvous, (2) maximize system throughput, (3) minimize primary user interference, and (4) minimize collisions among CR nodes.

  2. Endoscopic rendezvous procedure for ureteral iatrogenic detachment: report of a case series with long-term outcomes.

    Science.gov (United States)

    Pastore, Antonio Luigi; Palleschi, Giovanni; Silvestri, Luigi; Leto, Antonino; Autieri, Domenico; Ripoli, Andrea; Maggioni, Cristina; Al Salhi, Yazan; Carbone, Antonio

    2015-04-01

    Injury to the ureter is the most common urologic complication of pelvic surgery, with an incidence that ranges from 1% to 10%. Most cases of ureteral injuries are related to gynecologic procedures. The ureter is particularly vulnerable to detachment or ligation during hysterectomy because of its position from the lateral edge of the cervix. We report a case series of female patients who underwent the ureteral rendezvous procedure for ureteral detachment. Between January 2009 and April 2013, 18 ureteral rendezvous procedures were performed for patients with complete detachment. We assessed the operative and clinical outcomes of these patients over a mean follow-up duration of 26.5 months and describe the three most representative cases. The endoscopic rendezvous technique was performed in all cases to manage ureteral detachment. CT urography at discharge and 6 and 12 months after discharge confirmed the restoration of ureteral integrity without any leakage in 66% (12/18) patients, indicated ureteral stenosis in 22% (4/18) patients, and indicated ureteral leakage in 12% (2/18) patients. The overall long-term success rate for all 18 patients was 78% (14/18) at a mean follow-up of 26.5 months. The endoscopic rendezvous procedure reduces the need for invasive open surgical repair and represents the optimal initial option in patients with iatrogenic ureteral lesions before invasive procedures with higher morbidity are attempted.

  3. Rendezvous technique for recanalization of long-segmental chronic total occlusion above the knee following unsuccessful standard angioplasty.

    Science.gov (United States)

    Cao, Jun; Lu, Hai-Tao; Wei, Li-Ming; Zhao, Jun-Gong; Zhu, Yue-Qi

    2016-04-01

    To assess the technical feasibility and efficacy of the rendezvous technique, a type of subintimal retrograde wiring, for the treatment of long-segmental chronic total occlusions above the knee following unsuccessful standard angioplasty. The rendezvous technique was attempted in eight limbs of eight patients with chronic total occlusions above the knee after standard angioplasty failed. The clinical symptoms and ankle-brachial index were compared before and after the procedure. At follow-up, pain relief, wound healing, limb salvage, and the presence of restenosis of the target vessels were evaluated. The rendezvous technique was performed successfully in seven patients (87.5%) and failed in one patient (12.5%). Foot pain improved in all seven patients who underwent successful treatment, with ankle-brachial indexes improving from 0.23 ± 0.13 before to 0.71 ± 0.09 after the procedure (P rendezvous technique is a feasible and effective treatment for chronic total occlusions above the knee when standard angioplasty fails. © The Author(s) 2015.

  4. Endo-laparoscopic rendezvous approach for pericardia with gastric posterior wall of gastrointestinal stromal tumor: Analysis of 52 consecutive cases

    Directory of Open Access Journals (Sweden)

    Po Ding

    2014-01-01

    Conclusions: Endo-laparoscopic rendezvous approach is considered to represent the next revolution in surgery. The new technique is reliable and effective in clinical application, due to the advantages of accurate and quick localization for pericardial GIST within gastric posterior wall.

  5. Usefulness of the 'Rendezvous' Technique in Living Related Right Liver Donors with Postoperative Biliary Leakage from Bile Duct Anastomosis

    International Nuclear Information System (INIS)

    Miraglia, R.; Traina, M.; Maruzzelli, L.; Caruso, S.; Di Pisa, M.; Gruttadauria, S.; Luca, A.; Gridelli, B.

    2008-01-01

    This is a report on two cases of large bile leak following right hepatectomy performed for living related liver transplantation, originating from the stump of the ligated right bile duct, and treated with the placement of large percutaneous biliary catheters through a combined percutaneous transhepatic and endoscopic approach (rendezvous technique).

  6. PSD Increment Consumption Guidance

    Science.gov (United States)

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  7. Pain associated with liver biopsies through percutaneous approach under sono-graphic guidance-a cross sectional pilot study in a tertiary care hospital

    International Nuclear Information System (INIS)

    Baig, M.A.

    2015-01-01

    Pain is one of the most common and feared complication of percutaneous liver biopsy under local anaesthesia using sonographic guidance. This observational study was set to judge the intensity of pain felt by adult patients presenting for percutaneous liver biopsy with known/suspected underlying hepatic pathology. Methods: This observational cross sectional study which was piloted on 10% of the original sample size was conducted at Aga Khan University Hospital, Karachi. Study population was the adult patients coming for percutaneous liver biopsy at the Department of Radiology. Descriptive statistics were run, data was checked for normality. Means and Standard deviations were done for continuous variables and where data was skewed, median with inter quartile range was computed. Later data was clumped in categories, frequency and percentages were reported for categorical variables. Graphical representation of data was done. Results: A total of 50 patients were recruited. Minimum pain reported on visual analogue scale (VAS) was 0 and maximum as 4.30% of patients rated 3 and similarly 30% of the people rated 4 on the VAS. Mean pain experienced was 2.7 ± 1.11 and a median of 3 on VAS. This indicates that a minority of patients in our survey had a complaint of mild pain during the procedure. Conclusions: Percutaneous liver biopsy is a very safe procedure and minimal pain was felt by a minority of patients whereas the rest showed satisfaction from the procedure with no post procedural complaints. (author)

  8. Determination of Eros Physical Parameters for Near Earth Asteroid Rendezvous Orbit Phase Navigation

    Science.gov (United States)

    Miller, J. K.; Antreasian, P. J.; Georgini, J.; Owen, W. M.; Williams, B. G.; Yeomans, D. K.

    1995-01-01

    Navigation of the orbit phase of the Near Earth steroid Rendezvous (NEAR) mission will re,quire determination of certain physical parameters describing the size, shape, gravity field, attitude and inertial properties of Eros. Prior to launch, little was known about Eros except for its orbit which could be determined with high precision from ground based telescope observations. Radar bounce and light curve data provided a rough estimate of Eros shape and a fairly good estimate of the pole, prime meridian and spin rate. However, the determination of the NEAR spacecraft orbit requires a high precision model of Eros's physical parameters and the ground based data provides only marginal a priori information. Eros is the principal source of perturbations of the spacecraft's trajectory and the principal source of data for determining the orbit. The initial orbit determination strategy is therefore concerned with developing a precise model of Eros. The original plan for Eros orbital operations was to execute a series of rendezvous burns beginning on December 20,1998 and insert into a close Eros orbit in January 1999. As a result of an unplanned termination of the rendezvous burn on December 20, 1998, the NEAR spacecraft continued on its high velocity approach trajectory and passed within 3900 km of Eros on December 23, 1998. The planned rendezvous burn was delayed until January 3, 1999 which resulted in the spacecraft being placed on a trajectory that slowly returns to Eros with a subsequent delay of close Eros orbital operations until February 2001. The flyby of Eros provided a brief glimpse and allowed for a crude estimate of the pole, prime meridian and mass of Eros. More importantly for navigation, orbit determination software was executed in the landmark tracking mode to determine the spacecraft orbit and a preliminary shape and landmark data base has been obtained. The flyby also provided an opportunity to test orbit determination operational procedures that will be

  9. Conversion of Percutaneous Cholecystostomy to Endoscopic Gallbladder Stenting by Using the Rendezvous Technique.

    Science.gov (United States)

    Nam, Kwangwoo; Choi, Jun-Ho

    2017-05-01

    We report the successful conversion of percutaneous cholecystostomy (PC) to endoscopic transpapillary gallbladder stenting (ETGS) with insertion of an antegrade guidewire into the duodenum. An 84-year-old man presented with severe acute cholecystitis and septic shock. He had significant comorbidities, and emergent PC was successfully performed. Subsequent ETGS was attempted but unsuccessful owing to difficulties with cystic duct cannulation. However, via the PC tract, the guidewire was passed antegradely into the duodenum, and ETGS with a double-pigtail plastic stent was successfully performed with the rendezvous technique. The PC tube was removed, and no recurrence was reported during the 17-month follow-up period. Conversion of PC to ETGS is a viable option in patients with acute cholecystitis who are not candidates for surgery. Antegrade guidewire insertion via the PC tract may increase the success rate of conversion and decrease the risk of procedure-related complications.

  10. Robust adaptive backstepping neural networks control for spacecraft rendezvous and docking with input saturation.

    Science.gov (United States)

    Xia, Kewei; Huo, Wei

    2016-05-01

    This paper presents a robust adaptive neural networks control strategy for spacecraft rendezvous and docking with the coupled position and attitude dynamics under input saturation. Backstepping technique is applied to design a relative attitude controller and a relative position controller, respectively. The dynamics uncertainties are approximated by radial basis function neural networks (RBFNNs). A novel switching controller consists of an adaptive neural networks controller dominating in its active region combined with an extra robust controller to avoid invalidation of the RBFNNs destroying stability of the system outside the neural active region. An auxiliary signal is introduced to compensate the input saturation with anti-windup technique, and a command filter is employed to approximate derivative of the virtual control in the backstepping procedure. Globally uniformly ultimately bounded of the relative states is proved via Lyapunov theory. Simulation example demonstrates effectiveness of the proposed control scheme. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Conversion of Percutaneous Cholecystostomy to Endoscopic Gallbladder Stenting by Using the Rendezvous Technique

    Directory of Open Access Journals (Sweden)

    Kwangwoo Nam

    2017-05-01

    Full Text Available We report the successful conversion of percutaneous cholecystostomy (PC to endoscopic transpapillary gallbladder stenting (ETGS with insertion of an antegrade guidewire into the duodenum. An 84-year-old man presented with severe acute cholecystitis and septic shock. He had significant comorbidities, and emergent PC was successfully performed. Subsequent ETGS was attempted but unsuccessful owing to difficulties with cystic duct cannulation. However, via the PC tract, the guidewire was passed antegradely into the duodenum, and ETGS with a double-pigtail plastic stent was successfully performed with the rendezvous technique. The PC tube was removed, and no recurrence was reported during the 17-month follow-up period. Conversion of PC to ETGS is a viable option in patients with acute cholecystitis who are not candidates for surgery. Antegrade guidewire insertion via the PC tract may increase the success rate of conversion and decrease the risk of procedure-related complications.

  12. Observer-Based Stabilization of Spacecraft Rendezvous with Variable Sampling and Sensor Nonlinearity

    Directory of Open Access Journals (Sweden)

    Zhuoshi Li

    2013-01-01

    Full Text Available This paper addresses the observer-based control problem of spacecraft rendezvous with nonuniform sampling period. The relative dynamic model is based on the classical Clohessy-Wiltshire equation, and sensor nonlinearity and sampling are considered together in a unified framework. The purpose of this paper is to perform an observer-based controller synthesis by using sampled and saturated output measurements, such that the resulting closed-loop system is exponentially stable. A time-dependent Lyapunov functional is developed which depends on time and the upper bound of the sampling period and also does not grow along the input update times. The controller design problem is solved in terms of the linear matrix inequality method, and the obtained results are less conservative than using the traditional Lyapunov functionals. Finally, a numerical simulation example is built to show the validity of the developed sampled-data control strategy.

  13. Leak or Fistula After Sleeve Gastrectomy: Treatment with Pigtail Drain by the Rendezvous Technique.

    Science.gov (United States)

    Soufron, Jacques

    2015-10-01

    After a sleeve gastrectomy, a leak or fistula is a serious complication. Laparoscopic drainage, drainage under US or CT scan control, or endoscopic insertion of a stent can be used, but a major re-operation is sometimes unavoidable. Endoscopic drainage with a pigtail catheter could give more success and fewer complications, but the insertion of the drain is not always possible nor does it always provide a perfect drainage. If a laparoscopic second look appears necessary, it is possible to insert a pigtail drain laparoscopically, but under endoscopic control, ensuring a correct positioning of the drain both in the peritoneal cavity and in the gastric tube. This simultaneous "rendezvous" technique could combine in this situation the advantages of purely surgical techniques and of purely endoscopic or image-guided techniques.

  14. The Undergraduate Education Studies Dissertation: Philosophical Reflections upon Tacit Empiricism in Textbook Guidance and the Latent Capacity of Argumentation

    Science.gov (United States)

    Gibson, Howard; Garside, Darren

    2017-01-01

    The final-year undergraduate dissertation is commonplace in Education Studies programmes across the world and yet its philosophical assumptions are complex and not always questioned. In England there is evidence to suggest a tacit preference for empiricism in textbooks designed to support early researchers. This brings, we suggest, problems…

  15. Guidance for deciding upon use of primary mixed methods studies in research synthesis : Lessons learned in childhood trauma

    NARCIS (Netherlands)

    Boeije, H.; van Wesel, F.; Slagt, M.

    2014-01-01

    When reviewing literature, mixed methods studies (MMS) are increasingly retrieved, yet it is unclear how they should be dealt with in a research synthesis. In this article we examine the inclusion of primary MMS in research synthesis, based on experiences with a meta-analysis (MA) and a qualitative

  16. Guidance for deciding upon use of primary mixed methods studies in research synthesis: lessons learned in childhood trauma

    NARCIS (Netherlands)

    Boeije, H.R.; van Wesel, F.; Slagt, M.I.

    2014-01-01

    When reviewing literature, mixed methods studies (MMS) are increasingly retrieved, yet it is unclear how they should be dealt with in a research synthesis. In this article we examine the inclusion of primary MMS in research synthesis, based on experiences with a meta-analysis (MA) and a qualitative

  17. Guidance for deciding upon use of primary mixed methods studies in research synthesis: lessons learned in childhood trauma.

    NARCIS (Netherlands)

    Boeije, H.; Wesel, F. van; Slagt, M.

    2014-01-01

    When reviewing literature, mixed methods studies (MMS) are increasingly retrieved, yet it is unclear how they should be dealt with in a research synthesis. In this article we examine the inclusion of primary MMS in research synthesis, based on experiences with a meta-analysis (MA) and a qualitative

  18. A modified technique reduced operative time of laparoendoscopic rendezvous endoscopic retrograde cholangiopancreatography combined with laparoscopic cholecystectomy for concomitant gallstone and common bile ductal stone.

    Science.gov (United States)

    Liu, Wei; Wang, Qunwei; Xiao, Jing; Zhao, Liying; Huang, Jiangsheng; Tan, Zhaohui; Li, Pengfei

    2014-01-01

    Laparoendoscopic rendezvous (LERV) endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic cholecystectomy (LC+ERCP/LERV) are considered an optimal approach for concomitant gallstones and common bile duct stones. The rendezvous technique is essential for the success of procedure. We applied two different LERV techniques, traditional technique and modified technique, in 60 consecutive cases from January 2011 to November 2012. 32 cases who underwent modified technique (group 1) from February 2012 to November 2012 were retrospectively compared to 28 cases (group 2) who underwent traditional technique from January 2011 to January 2012. There was no significant difference between two groups with respect to preoperative demographic features. Although the difference was not statistically significant, the procedure was successfully performed in 31 cases (96.9%) in group 1 and 24 cases (86.2%) in group 2. The mean operative time and time of endoscopic part were 82.6 ± 19.6 min and 26.5 ± 5.99 min in group 1 which were significantly shorter than those in group 2 (118.0 ± 23.1 min and 58.7 ± 13.3 min, resp.). There was no postoperative pancreatitis and mortality in both groups. The mean hospital stay, blood loss, incidence of complications, and residual stone were of no difference in both groups. This study proved that this modified technique can effectively reduce the operative time and time of endoscopic part of LC+ERCP/LERV compared with traditional technique.

  19. A Modified Technique Reduced Operative Time of Laparoendoscopic Rendezvous Endoscopic Retrograde Cholangiopancreatography Combined with Laparoscopic Cholecystectomy for Concomitant Gallstone and Common Bile Ductal Stone

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2014-01-01

    Full Text Available Laparoendoscopic rendezvous (LERV endoscopic retrograde cholangiopancreatography (ERCP and laparoscopic cholecystectomy (LC+ERCP/LERV are considered an optimal approach for concomitant gallstones and common bile duct stones. The rendezvous technique is essential for the success of procedure. We applied two different LERV techniques, traditional technique and modified technique, in 60 consecutive cases from January 2011 to November 2012. 32 cases who underwent modified technique (group 1 from February 2012 to November 2012 were retrospectively compared to 28 cases (group 2 who underwent traditional technique from January 2011 to January 2012. There was no significant difference between two groups with respect to preoperative demographic features. Although the difference was not statistically significant, the procedure was successfully performed in 31 cases (96.9% in group 1 and 24 cases (86.2% in group 2. The mean operative time and time of endoscopic part were 82.6 ± 19.6 min and 26.5 ± 5.99 min in group 1 which were significantly shorter than those in group 2 (118.0 ± 23.1 min and 58.7 ± 13.3 min, resp.. There was no postoperative pancreatitis and mortality in both groups. The mean hospital stay, blood loss, incidence of complications, and residual stone were of no difference in both groups. This study proved that this modified technique can effectively reduce the operative time and time of endoscopic part of LC+ERCP/LERV compared with traditional technique.

  20. Identifying indications for percutaneous (PTC) vs. endoscopic ultrasound (EUS)- guided "rendezvous" procedure in biliary obstruction and incomplete endoscopic retrograde cholangiography (ERC).

    Science.gov (United States)

    Albert, J G; Finkelmeier, F; Friedrich-Rust, M; Kronenberger, B; Trojan, J; Zeuzem, S; Sarrazin, C

    2014-10-01

    The variety of rendezvous (RV) procedures has recently been extended by EUS- and PTCD-guided procedures as a complementary means to conventional ERCP. We have identified indication criteria and the potential of biliary PTCD-guided vs. EUS-guided RV. Consecutive patients with bile duct obstruction who underwent RV were included. In all, ERCP alone was unable to achieve treatment success. Indication, technical success, and outcome in PTCD- vs. EUS-guided RV were retrospectively compared to identify criteria that indicate preference of RV technique. Site of obstruction, clinical scenario (stenosis with abscess vs. no abscess) and reason for previous failure of ERC were evaluated. In 32 patients, three different indications for RV procedures were identified: First, a one-step access to assist in failed ERCP (type 1, intra-ductal RV); second, temporary drainage for prolonged treatment of complex biliary disease (type 2, intra-ductal RV), and drainage of cholangio-abscess with re-establishing bile outflow (type 3, intra-abscess RV). Indication of PTCD- vs. EUS-guided rendezvous was competitive in type 1, but exclusive in favor of PTCD in types 2 and 3. The site of biliary obstruction indicated the anatomic location of RV procedures. This classification may help to define inclusion criteria for prospective studies on biliary RV procedures. Choice of therapeutic strategy depends on the anatomic location of the biliary obstruction and the type of the biliary lesion. PTCD-guided RV might improve outcome in cholangio-abscess. © Georg Thieme Verlag KG Stuttgart · New York.

  1. FDA-EPA Public Health Guidance on Fish Consumption: A Case Study on Informal Interagency Cooperation in "Shared Regulatory Space".

    Science.gov (United States)

    Holden, Mark

    2015-01-01

    This article is a case study on how administrative agencies interact with each other in cases of shared regulatory jurisdiction. The theoretical literature on the topic of overlapping jurisdiction both (1) makes predictions about how agencies are expected to behave when they share jurisdiction, and (2) in recent iterations argues that overlapping jurisdiction can confer unique policymaking benefits. Through the lens of that theoretical literature, this article examines the relations between the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) regarding the public health risks posed by mercury in fish. It concludes that the FDA-EPA case study (1) corroborates the extant theoretical accounts of how agencies behave in cases of overlapping jurisdiction, (2) supports the conclusion of the recent scholarship that overlapping jurisdiction can confer unique policy benefits, and (3) reveals a few wrinkles not given adequate treatment in the extant literature.

  2. Review of LCA studies of solid waste management systems--part II: methodological guidance for a better practice.

    Science.gov (United States)

    Laurent, Alexis; Clavreul, Julie; Bernstad, Anna; Bakas, Ioannis; Niero, Monia; Gentil, Emmanuel; Christensen, Thomas H; Hauschild, Michael Z

    2014-03-01

    Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. A Formal Investigation of the Organization of Guidance Behavior: Implications for Humans and Autonomous Guidance

    Science.gov (United States)

    Kong, Zhaodan

    Guidance behavior generated either by artificial agents or humans has been actively studied in the fields of both robotics and cognitive science. The goals of these two fields are different. The former is the automatic generation of appropriate or even optimal behavior, while the latter is the understanding of the underlying mechanism. Their challenges, though, are closely related, the most important one being the lack of a unified, formal and grounded framework where the guidance behavior can be modeled and studied. This dissertation presents such a framework. In this framework, guidance behavior is analyzed as the closed-loop dynamics of the whole agent-environment system. The resulting dynamics give rise to interaction patterns. The central points of this dissertation are that: first of all, these patterns, which can be explained in terms of symmetries that are inherent to the guidance behavior, provide building blocks for the organization of behavior; second, the existence of these patterns and humans' organization of their guidance behavior based on these patterns are the reasons that humans can generate successful behavior in spite of all the complexities involved in the planning and control. This dissertation first gives an overview of the challenges existing in both scientific endeavors, such as human and animal spatial behavior study, and engineering endeavors, such as autonomous guidance system design. It then lays out the foundation for our formal framework, which states that guidance behavior should be interpreted as the collection of the closed-loop dynamics resulting from the agent's interaction with the environment. The following, illustrated by examples of three different UAVs, shows that the study of the closed-loop dynamics should not be done without the consideration of vehicle dynamics, as is the common practice in some of the studies in both autonomous guidance and human behavior analysis. The framework, the core concepts of which are

  4. Resolving external pancreatic fistulas in patients with disconnected pancreatic duct syndrome: using rendezvous techniques to avoid surgery (with video).

    Science.gov (United States)

    Irani, Shayan; Gluck, Michael; Ross, Andrew; Gan, S Ian; Crane, Robert; Brandabur, John J; Hauptmann, Ellen; Fotoohi, Mehran; Kozarek, Richard A

    2012-09-01

    An external pancreatic fistula (EPF) generally results from an iatrogenic manipulation of a pancreatic fluid collection (PFC), such as walled-off pancreatic necrosis (WOPN). Severe necrotizing pancreatitis can lead to complete duct disruption, causing disconnected pancreatic duct syndrome (DPDS) with viable upstream pancreas draining out of a low-pressure fistula created surgically or by a percutaneous catheter. The EPF can persist for months to years, and distal pancreatectomy, often the only permanent solution, carries a high morbidity and defined mortality. To describe 3 endoscopic and percutaneous rendezvous techniques to completely resolve EPFs in the setting of DPDS. A retrospective review of a prospective database of 15 patients who underwent rendezvous internalization of EPFs. Tertiary-care pancreatic referral center. Fifteen patients between October 2002 and October 2011 with EPFs in the setting of DPDS and resolved WOPN. Three rendezvous techniques that combined endoscopic and percutaneous procedures to internalize EPFs by transgastric, transduodenal, or transpapillary methods. EPF resolution and morbidity. Fifteen patients (12 men) with a median age of 51 years (range 24-65 years) with EPFs and DPDS (cutoff/blowout of pancreatic duct, with inability to demonstrate upstream body/tail of pancreas on pancreatogram) resulting from severe necrotizing pancreatitis underwent 1 of 3 rendezvous procedures to eliminate the EPFs. All patients were either poor surgical candidates or refused surgery. At the time of the rendezvous procedure, WOPN had fully resolved, DPDS was confirmed on pancreatography, and the EPF had persisted for a median of 5 months (range 1-48 months), producing a median output of 200 mL/day (range 50-700 mL/day). The rendezvous technique in 10 patients used the existing percutaneous drainage fistula to puncture into the stomach/duodenum to deliver wires that were captured endoscopically. The transenteric fistula was dilated and two

  5. Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

    DEFF Research Database (Denmark)

    Laurent, Alexis; Clavreul, Julie; Bernstad, Anna

    2014-01-01

    conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements......Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper...... compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs. © 2013 Elsevier Ltd. All...

  6. Endoscopic Ultrasound-Guided Rendezvous Technique for Failed Biliary Cannulation in Benign and Resectable Malignant Biliary Disorders.

    Science.gov (United States)

    Shiomi, Hideyuki; Yamao, Kentaro; Hoki, Noriyuki; Hisa, Takeshi; Ogura, Takeshi; Minaga, Kosuke; Masuda, Atsuhiro; Matsumoto, Kazuya; Kato, Hironari; Kamada, Hideki; Goto, Daisuke; Imai, Hajime; Takenaka, Mamoru; Noguchi, Chishio; Nishikiori, Hidefumi; Chiba, Yasutaka; Kutsumi, Hiromu; Kitano, Masayuki

    2018-03-01

    Endoscopic ultrasound-guided rendezvous technique (EUS-RV) has emerged as an effective salvage method for unsuccessful biliary cannulation. However, its application for benign and resectable malignant biliary disorders has not been fully evaluated. To assess the efficacy and safety of EUS-RV for benign and resectable malignant biliary disorders. This was a multicenter prospective study from 12 Japanese referral centers. Patients who underwent EUS-RV after failed biliary cannulation for biliary disorder were candidates for this study. Inclusion criteria were unsuccessful biliary cannulation for therapeutic endoscopic retrograde cholangiopancreatography with benign and potentially resectable malignant biliary obstruction. Exclusion criteria included unresectable malignant biliary obstruction, inaccessible papillae due to surgically altered upper gastrointestinal anatomy or duodenal stricture, and previous sphincterotomy and/or biliary stent placement. The primary outcome was the technical success rate of biliary cannulation; procedure time, adverse events, and clinical outcomes were secondary outcomes. Twenty patients were prospectively enrolled. The overall technical success rate and median procedure time were 85% and 33 min, respectively. Guidewire manipulation using a 4-Fr tapered tip catheter contributed to the success in advancing the guidewire into the duodenum. Adverse events were identified in 15% patients, including 2 with biliary peritonitis and 1 mild pancreatitis. EUS-RV did not affect surgical maneuvers or complications associated with surgery, or postoperative course. EUS-RV may be a safe and feasible salvage method for unsuccessful biliary cannulation for benign or resectable malignant biliary disorders. Use of a 4-Fr tapered tip catheter may improve the overall EUS-RV success rate.

  7. Dual-energy compared to single-energy CT in pediatric imaging: a phantom study for DECT clinical guidance

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaowei; Servaes, Sabah; Darge, Kassa [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, The Perelman School of Medicine, Philadelphia, PA (United States); McCullough, William P. [University of Virginia Health System, Department of Radiology and Medical Imaging, Charlottesville, VA (United States); Mecca, Patricia [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2016-11-15

    Dual-energy CT technology is available on scanners from several vendors and offers significant advantages over classic single-energy CT technology in multiple clinical applications. Many studies have detailed dual-energy CT applications in adults and several have evaluated the relative radiation dose performance of dual-energy CT in adult imaging. However, little has been published on dual-energy CT imaging in the pediatric population, and the relative dose performance of dual-energy CT imaging in the pediatric population is not well described. When evaluating dual-energy CT technology for implementation into a routine clinical pediatric imaging practice, the radiation dose implications must be considered, and when comparing relative CT dose performance, image quality must also be evaluated. Therefore the purpose of this study is to develop dual-energy CT scan protocols based on our optimized single-energy scan protocols and compare the dose. We scanned the head, chest and abdomen regions of pediatric-size anthropomorphic phantoms with contrast inserts, using our optimized single-energy clinical imaging protocols on a Siemens Flash {sup registered} CT scanner. We then scanned the phantoms in dual-energy mode using matching image-quality reference settings. The effective CT dose index volume (CTDI{sub vol}) of the scans was used as a surrogate for relative dose in comparing the single- and dual-energy scans. Additionally, we evaluated image quality using visual assessment and contrast-to-noise ratio. Dual-energy CT scans of the head and abdomen were dose-neutral for all three phantoms. Dual-energy CT scans of the chest showed a relative dose increase over the single-energy scan for 1- and 5-year-old child-based age-equivalent phantoms, ranging 11-20%. Quantitative analysis of image quality showed no statistically significant difference in image quality between the single-energy and dual-energy scans. There was no clinically significant difference in image quality by

  8. Dual-energy compared to single-energy CT in pediatric imaging: a phantom study for DECT clinical guidance

    International Nuclear Information System (INIS)

    Zhu, Xiaowei; Servaes, Sabah; Darge, Kassa; McCullough, William P.; Mecca, Patricia

    2016-01-01

    Dual-energy CT technology is available on scanners from several vendors and offers significant advantages over classic single-energy CT technology in multiple clinical applications. Many studies have detailed dual-energy CT applications in adults and several have evaluated the relative radiation dose performance of dual-energy CT in adult imaging. However, little has been published on dual-energy CT imaging in the pediatric population, and the relative dose performance of dual-energy CT imaging in the pediatric population is not well described. When evaluating dual-energy CT technology for implementation into a routine clinical pediatric imaging practice, the radiation dose implications must be considered, and when comparing relative CT dose performance, image quality must also be evaluated. Therefore the purpose of this study is to develop dual-energy CT scan protocols based on our optimized single-energy scan protocols and compare the dose. We scanned the head, chest and abdomen regions of pediatric-size anthropomorphic phantoms with contrast inserts, using our optimized single-energy clinical imaging protocols on a Siemens Flash "r"e"g"i"s"t"e"r"e"d CT scanner. We then scanned the phantoms in dual-energy mode using matching image-quality reference settings. The effective CT dose index volume (CTDI_v_o_l) of the scans was used as a surrogate for relative dose in comparing the single- and dual-energy scans. Additionally, we evaluated image quality using visual assessment and contrast-to-noise ratio. Dual-energy CT scans of the head and abdomen were dose-neutral for all three phantoms. Dual-energy CT scans of the chest showed a relative dose increase over the single-energy scan for 1- and 5-year-old child-based age-equivalent phantoms, ranging 11-20%. Quantitative analysis of image quality showed no statistically significant difference in image quality between the single-energy and dual-energy scans. There was no clinically significant difference in image quality

  9. Guidance for the utility of linear models in meta-analysis of genetic association studies of binary phenotypes.

    Science.gov (United States)

    Cook, James P; Mahajan, Anubha; Morris, Andrew P

    2017-02-01

    Linear mixed models are increasingly used for the analysis of genome-wide association studies (GWAS) of binary phenotypes because they can efficiently and robustly account for population stratification and relatedness through inclusion of random effects for a genetic relationship matrix. However, the utility of linear (mixed) models in the context of meta-analysis of GWAS of binary phenotypes has not been previously explored. In this investigation, we present simulations to compare the performance of linear and logistic regression models under alternative weighting schemes in a fixed-effects meta-analysis framework, considering designs that incorporate variable case-control imbalance, confounding factors and population stratification. Our results demonstrate that linear models can be used for meta-analysis of GWAS of binary phenotypes, without loss of power, even in the presence of extreme case-control imbalance, provided that one of the following schemes is used: (i) effective sample size weighting of Z-scores or (ii) inverse-variance weighting of allelic effect sizes after conversion onto the log-odds scale. Our conclusions thus provide essential recommendations for the development of robust protocols for meta-analysis of binary phenotypes with linear models.

  10. Air/Superfund National Technical Guidance Study Series. Data Base of emission-rate-measurement projects. Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Eklund, B.; Petrinec, C.; Ranum, D.; Howlett, L.

    1991-06-01

    A compilation and evaluation of Volatile Organic Compound (VOC) emission rate data was performed. The three primary objectives were (1) to determine typical averages and ranges of emissions for various types of sources; (2) to determine the degree of correlation between emission rate results from different sampling methods; and (3) to examine the effects of different variables on measured emission rates. Emission rate data are presented for 33 studies covering 13 types of emission sources. The sources include landfills, surface impoundments, waste water treatment systems, leaking underground storage tanks, soil piles and landfarms. The emission rate data were obtained by using the Emission Isolation Flux Chamber, Downhole Emissions Isolation Flux Chamber, the Concentration Profile method and the Transect method. For each source, the total non-methane hydrocarbon and benzene emission rates are reported along with three other compounds that had the highest emission rate. Source concentration data (e.g. concentration in soil or waste water) are also reported for comparison to the measured emission rates.

  11. Fine Guidance Sensing for Coronagraphic Observatories

    Science.gov (United States)

    Brugarolas, Paul; Alexander, James W.; Trauger, John T.; Moody, Dwight C.

    2011-01-01

    Three options have been developed for Fine Guidance Sensing (FGS) for coronagraphic observatories using a Fine Guidance Camera within a coronagraphic instrument. Coronagraphic observatories require very fine precision pointing in order to image faint objects at very small distances from a target star. The Fine Guidance Camera measures the direction to the target star. The first option, referred to as Spot, was to collect all of the light reflected from a coronagraph occulter onto a focal plane, producing an Airy-type point spread function (PSF). This would allow almost all of the starlight from the central star to be used for centroiding. The second approach, referred to as Punctured Disk, collects the light that bypasses a central obscuration, producing a PSF with a punctured central disk. The final approach, referred to as Lyot, collects light after passing through the occulter at the Lyot stop. The study includes generation of representative images for each option by the science team, followed by an engineering evaluation of a centroiding or a photometric algorithm for each option. After the alignment of the coronagraph to the fine guidance system, a "nulling" point on the FGS focal point is determined by calibration. This alignment is implemented by a fine alignment mechanism that is part of the fine guidance camera selection mirror. If the star images meet the modeling assumptions, and the star "centroid" can be driven to that nulling point, the contrast for the coronagraph will be maximized.

  12. 18 month observational study on efficacy of intraarticular hyaluronic acid (Hylan G-F 20 injections under ultrasound guidance in hip osteoarthritis

    Directory of Open Access Journals (Sweden)

    Cristiano Padalino

    2011-09-01

    Full Text Available Objective: To evaluate the efficacy and the tolerability of viscosupplementation (VS with hyaluronic acid (Hylan GF 20 in a cohort of 36 patients affected by hip osteoarthritis through a 18 months follow-up. Methods: Viscosupplementation was performed with an anteriorsagittal approach, under ultrasound guidance. 36 patients were administered hyaluronic acid intraarticularly in the hip, with a unique injection of Hylan G-F20, which could be repeated after at least 3 months. Treatment efficacy was assessed by functional index WOMAC, pain evaluation on a visual analogue scale and NSAID consumption. All such parameters were recorded at the time of the first injection and then 3, 6, 9, 12 and 18 months later. Results: Statistically significant reduction of all parameters was observed three months after the injection, and was still maintained at the timepoints 6, 9, 12 and 18 months. No local side effects have been observed, nor systemic complications. Conclusions: Our data show that viscosupplementation is a promising approach for hip osteoarthritis, providing beneficial effects in a long-tern follow up. Yet, the topic deserves further and wider studies, so to define the number of injections to administer and suggest a fit interval between subsequent injections.

  13. Comparison of Procalcitonin Guidance-Administered Antibiotics with Standard Guidelines on Antibiotic Therapy in Children with Lower Respiratory Tract Infections: A Retrospective Study in China.

    Science.gov (United States)

    Wu, Guo; Wu, Gao; Wu, Shuxie; Wu, Hanbin

    2017-01-01

    To establish the efficacy of an algorithm based on the biomarker procalcitonin (PCT) to reduce antibiotic exposure in pediatric patients with lower respiratory tract infection (LRTI). The clinical data of 357 patients (standard group (n = 174) using SAS 9.1.3 software. The overall adverse effect rates were similar in both the PCT and standard groups: 42 (22.95%) and 51 (29.31%), respectively. The length of hospital stay was not significantly different between the PCT (9.96 ± 5.81 days) and standard groups (10.58 ± 4.24 days) (difference: -0.62%; 95% CI: -1.68 to 0.43). Antibiotic prescribing rates were significantly different in the PCT group compared to the standard group: 54.64% versus 83.91% (difference: -29.26%; 95% CI: -38.31, -20.22; p = 0.23). Mean duration of antibiotic exposure in the PCT group (3.98 ± 2.17 days) was lower than the standard groups (6.66 ± 5.59 days) (difference: -2.68%; 95% CI: -3.21 to -2.16). This study showed that PCT guidance of antibiotic treatment in children and adolescents with LRTI reduced the duration of antibiotic exposure and antibiotic prescribing rates, but did not affect the adverse effect rate and length of hospital stay. © 2017 S. Karger AG, Basel.

  14. Appropriateness of clinical severity classification of new WHO childhood pneumonia guidance: a multi-hospital, retrospective, cohort study.

    Science.gov (United States)

    Agweyu, Ambrose; Lilford, Richard J; English, Mike

    2018-01-01

    Management of pneumonia in many low-income and middle-income countries is based on WHO guidelines that classify children according to clinical signs that define thresholds of risk. We aimed to establish whether some children categorised as eligible for outpatient treatment might have a risk of death warranting their treatment in hospital. We did a retrospective cohort study of children aged 2-59 months admitted to one of 14 hospitals in Kenya with pneumonia between March 1, 2014, and Feb 29, 2016, before revised WHO pneumonia guidelines were adopted in the country. We modelled associations with inpatient mortality using logistic regression and calculated absolute risks of mortality for presenting clinical features among children who would, as part of revised WHO pneumonia guidelines, be eligible for outpatient treatment (non-severe pneumonia). We assessed 16 162 children who were admitted to hospital in this period. 832 (5%) of 16 031 children died. Among groups defined according to new WHO guidelines, 321 (3%) of 11 788 patients with non-severe pneumonia died compared with 488 (14%) of 3434 patients with severe pneumonia. Three characteristics were strongly associated with death of children retrospectively classified as having non-severe pneumonia: severe pallor (adjusted risk ratio 5·9, 95% CI 5·1-6·8), mild to moderate pallor (3·4, 3·0-3·8), and weight-for-age Z score (WAZ) less than -3 SD (3·8, 3·4-4·3). Additional factors that were independently associated with death were: WAZ less than -2 to -3 SD, age younger than 12 months, lower chest wall indrawing, respiratory rate of 70 breaths per min or more, female sex, admission to hospital in a malaria endemic region, moderate dehydration, and an axillary temperature of 39°C or more. In settings of high mortality, WAZ less than -3 SD or any degree of pallor among children with non-severe pneumonia was associated with a clinically important risk of death. Our data suggest that admission to hospital

  15. Trajectory reshaping based guidance with impact time and angle constraints

    Directory of Open Access Journals (Sweden)

    Zhao Yao

    2016-08-01

    Full Text Available This study presents a novel impact time and angle constrained guidance law for homing missiles. The guidance law is first developed with the prior-assumption of a stationary target, which is followed by the practical extension to a maneuvering target scenario. To derive the closed-form guidance law, the trajectory reshaping technique is utilized and it results in defining a specific polynomial function with two unknown coefficients. These coefficients are determined to satisfy the impact time and angle constraints as well as the zero miss distance. Furthermore, the proposed guidance law has three additional guidance gains as design parameters which make it possible to adjust the guided trajectory according to the operational conditions and missile’s capability. Numerical simulations are presented to validate the effectiveness of the proposed guidance law.

  16. A comparison between endoscopic ultrasound-guided rendezvous and percutaneous biliary drainage after failed ERCP for malignant distal biliary obstruction.

    Science.gov (United States)

    Bill, Jason G; Darcy, Michael; Fujii-Lau, Larissa L; Mullady, Daniel K; Gaddam, Srinivas; Murad, Faris M; Early, Dayna S; Edmundowicz, Steven A; Kushnir, Vladimir M

    2016-09-01

    Selective biliary cannulation is unsuccessful in 5 % to 10 % of patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) for malignant distal biliary obstruction (MDBO). Percutaneous biliary drainage (PBD) has been the gold standard, but endoscopic ultrasound guided rendezvous (EUSr) have been increasingly used for biliary decompression in this patient population. Our aim was to compare the initial success rate, long-term efficacy, and safety of PBD and EUSr in relieving MDBO after failed ERC Patients and methods: A retrospective study involving 50 consecutive patients who had an initial failed ERCP for MDBO. Twenty-five patients undergoing EUSr between 2008 - 2014 were compared to 25 patients who underwent PBD immediately prior to the introduction of EUSr at our center (2002 - 2008). Comparisons were made between the two groups with regard to technical success, duration of hospital stay and adverse event rates after biliary decompression. The mean age at presentation was 66.5 (± 12.6 years), 28 patients (54.9 %) were female. The etiology of MDBO was pancreaticobiliary malignancy in 44 (88 %) and metastatic disease in 6 (12 %) cases. Biliary drainage was technically successful by EUSr in 19 (76 %) cases and by PBD in 25 (100 %) (P = 0.002). Median length of hospital stay after initial drainage was 1 day in the EUSr group vs 5 days in PBD group (P = 0.02). Repeat biliary intervention was required for 4 patients in the EUSr group and 15 in the PBD group (P = 0.001). Initial technical success with EUSr was significantly lower than with PBD, however when EUSr was successful, patients had a significantly shorter post-procedure hospital stay and required fewer follow-up biliary interventions. Meeting presentations: Annual Digestive Diseases Week 2015.

  17. Virtual Ultrasound Guidance for Inexperienced Operators

    Science.gov (United States)

    Caine, Timothy; Martin, David

    2012-01-01

    Medical ultrasound or echocardiographic studies are highly operator-dependent and generally require lengthy training and internship to perfect. To obtain quality echocardiographic images in remote environments, such as on-orbit, remote guidance of studies has been employed. This technique involves minimal training for the user, coupled with remote guidance from an expert. When real-time communication or expert guidance is not available, a more autonomous system of guiding an inexperienced operator through an ultrasound study is needed. One example would be missions beyond low Earth orbit in which the time delay inherent with communication will make remote guidance impractical. The Virtual Ultrasound Guidance system is a combination of hardware and software. The hardware portion includes, but is not limited to, video glasses that allow hands-free, full-screen viewing. The glasses also allow the operator a substantial field of view below the glasses to view and operate the ultrasound system. The software is a comprehensive video program designed to guide an inexperienced operator through a detailed ultrasound or echocardiographic study without extensive training or guidance from the ground. The program contains a detailed description using video and audio to demonstrate equipment controls, ergonomics of scanning, study protocol, and scanning guidance, including recovery from sub-optimal images. The components used in the initial validation of the system include an Apple iPod Classic third-generation as the video source, and Myvue video glasses. Initially, the program prompts the operator to power-up the ultrasound and position the patient. The operator would put on the video glasses and attach them to the video source. After turning on both devices and the ultrasound system, the audio-video guidance would then instruct on patient positioning and scanning techniques. A detailed scanning protocol follows with descriptions and reference video of each view along with

  18. Treatment of adolescent patients with class II division 1 malocclusion using Eruption guidance appliance: A comparative study with Twin-block and Activator-Headgear appliances.

    Science.gov (United States)

    Nilsson, Jenny Jiayan Luo; Shu, Xiaochen; Magnusson, Britt Hedenberg; Burt, Idil Alatli

    2016-01-01

    The aim of this study was to evaluate the compliance and short-term effects of eruption guidance appliance (EGA) in adolescents with class II division 1 malocclusion in comparison with twin-block appliance (TBA) and activator-headgear appliance (A-HG). Dental records of 1886 patients were viewed in this retrospective study 129 patients treated with one of these three functional appliances were identified. 123 fulfilled the inclusion criteria and data were extracted from the dental records. Gender, age, compliance, overjet change at every visit, number of appliance breakages and number of emergency visits apart from appliance breakage were studied. The data were analyzed with Chi-square test, General Linear Model and Fisher scoring test. Results showed that 47 patients were treated with EGA, 38 patients with TBA and 38 patients with A-HG. Mean ages starting the treatment were slightly lower with EGA (11.5 years) than with TBA (12.3 years) and A-HG (11.8 years). Non-compliance was higher in the EGA group (31.9%) than TBA group (26.3%) and A-HG group (23.7%). Mean overjet reduction per month was 0.6 mm for EGA which was lower than TBA group (0.7 mm) and A-HG groups (0.7 mm).The number of emergency visits and appliance breakage were lower in EGA group. However, there was no statistically significant difference between the 3 groups regarding ages,compliance, mean overjet reduction, emergency visits and appliance breakage aspects. In conclusion, this study indicates that EGA is an alternative choice in the treatment of adolescent patients with class II division 1 malocclusion. However, long-term follow-up and cephalometric prospective study should be performed to continue our understanding more about the mechanisms of EGA and more definite conclusions can be made.

  19. An Assessment of the Implementation of Guidance and Counselling ...

    African Journals Online (AJOL)

    This paper is based on a research study carried out by the author in 2003. The study assessed how Guidance and Counselling Programmes were being implemented in Gweru urban secondary schools at Ordinary level. The assessment focused on such key elements in Guidance and Counselling as time allocation, ...

  20. International guidance activities

    International Nuclear Information System (INIS)

    Richardson, Allan C.B.

    1989-01-01

    International principles for setting Protective Action Guides (PAGs) are contained in two key documents that contain identical statements. One is Publication Number 40 of the ICRP, which was issued in 1985. The title is 'Protection of the Public in the Event of Major Radiation Accidents, Principles for Planning'. The other is the IAEA's Safety Series Publication Number 72, also issued in 1985, written by many of the same authors and titled, 'Principles for Establishing Intervention Levels'. The principles that were set forth in these documents were identical, were incomplete, and they are, unfortunately, the only principles that are now in effect, while proposed revisions go through one draft after another. There are several such draft revisions that are of significance. The most important is that of the ICRP. The basic guidance that applies to most planned exposure to radiation is ICRP Publication 26. That document has been under revision by the Commission for a number of years, and the new version will, for the first time, include recommendations for emergency response. They are now getting close to closure, and I think it should be a very much improved and useful document. But it isn't finished yet. Such guidance doesn't get developed in a vacuum, and there have been a couple of parallel efforts which have provided significant input to the ICRP, which is essentially a behind-closed-doors effort. These other efforts are more open. One of these is being carried out within the IAEA, which has convened annual meetings of national experts for a number of years in Vienna, to generate a replacement for Safety Series No. 72, mentioned earlier. There is a meeting scheduled this December to complete this effort; and, hopefully, we will reach closure at that meeting on at least the basic principles. The Nuclear Energy Agency (NEA) has also been at work. It has convened a group of experts from member nations that have been developing recommendations. There is an overlap

  1. RH Packaging Program Guidance

    International Nuclear Information System (INIS)

    2006-01-01

    The purpose of this program guidance document is to provide the technical requirements for use, operation, inspection, and maintenance of the RH-TRU 72-B Waste Shipping Package and directly related components. This document complies with the requirements as specified in the RH-TRU 72-B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the C of C shall govern. The C of C states: 'each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, Operating Procedures, of the application.' It further states: 'each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, Acceptance Tests and Maintenance Program of the Application.' Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M and O) Contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRC-approved, users need to be familiar with 10 Code of Federal Regulations (CFR) 1.8, 'Deliberate Misconduct.' Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) shall be notified immediately. CBFO will evaluate the issue and notify the NRC if required. In accordance with 10 CFR Part 71, 'Packaging and Transportation of Radioactive Material,' certificate holders, packaging users, and contractors or subcontractors who use, design, fabricate, test, maintain, or modify the packaging shall post copies of (1) 10 CFR Part 21, 'Reporting of Defects and Noncompliance,' regulations, (2) Section 206 of the Energy Reorganization Act of 1974, and (3) NRC Form 3, Notice to Employees. These documents must be posted in a conspicuous location where the activities subject to these

  2. RH Packaging Program Guidance

    International Nuclear Information System (INIS)

    2008-01-01

    The purpose of this program guidance document is to provide the technical requirements for use, operation, inspection, and maintenance of the RH-TRU 72-B Waste Shipping Package (also known as the 'RH-TRU 72-B cask') and directly related components. This document complies with the requirements as specified in the RH-TRU 72-B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the C of C shall govern. The C of C states: 'each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, Operating Procedures, of the application.' It further states: 'each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, Acceptance Tests and Maintenance Program of the Application.' Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M and O) Contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRC-approved, users need to be familiar with Title 10 Code of Federal Regulations (CFR) 71.8, 'Deliberate Misconduct.' Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) shall be notified immediately. The CBFO will evaluate the issue and notify the NRC if required.In accordance with 10 CFR Part 71, 'Packaging and Transportation of Radioactive Material,' certificate holders, packaging users, and contractors or subcontractors who use, design, fabricate, test, maintain, or modify the packaging shall post copies of (1) 10 CFR Part 21, 'Reporting of Defects and Noncompliance,' regulations, (2) Section 206 of the Energy Reorganization Act of 1974, and (3) NRC Form 3, Notice to Employees. These documents must be posted in a conspicuous

  3. Integrating mechanisms of visual guidance in naturalistic language production.

    Science.gov (United States)

    Coco, Moreno I; Keller, Frank

    2015-05-01

    Situated language production requires the integration of visual attention and linguistic processing. Previous work has not conclusively disentangled the role of perceptual scene information and structural sentence information in guiding visual attention. In this paper, we present an eye-tracking study that demonstrates that three types of guidance, perceptual, conceptual, and structural, interact to control visual attention. In a cued language production experiment, we manipulate perceptual (scene clutter) and conceptual guidance (cue animacy) and measure structural guidance (syntactic complexity of the utterance). Analysis of the time course of language production, before and during speech, reveals that all three forms of guidance affect the complexity of visual responses, quantified in terms of the entropy of attentional landscapes and the turbulence of scan patterns, especially during speech. We find that perceptual and conceptual guidance mediate the distribution of attention in the scene, whereas structural guidance closely relates to scan pattern complexity. Furthermore, the eye-voice span of the cued object and its perceptual competitor are similar; its latency mediated by both perceptual and structural guidance. These results rule out a strict interpretation of structural guidance as the single dominant form of visual guidance in situated language production. Rather, the phase of the task and the associated demands of cross-modal cognitive processing determine the mechanisms that guide attention.

  4. A Study to Determine the Effects of a Comprehensive and Experiential System of Vocational Guidance and Career Development on Junior High School Pupils. Final Report.

    Science.gov (United States)

    Ehresman, Norman D.; Vincent, Roger D.

    Comprehensive work experience and vocational guidance activities were established at the middle school level and their effects on career maturity and attitudes toward school of ninth graders were tested. The project was conducted at the Bowling Green Junior High School (Kentucky) during the academic school year of 1975-76. (The school supports a…

  5. Combined Radial and Femoral Access Strategy and Radial-Femoral Rendezvous in Patients With Long and Complex Iliac Occlusions.

    Science.gov (United States)

    Hanna, Elias B; Mogabgab, Owen N; Baydoun, Hassan

    2018-01-01

    We present cases of complex, calcified iliac occlusive disease revascularized via a combined radial-femoral access strategy. Through a 6-French, 125-cm transradial guiding catheter, antegrade guidewires and catheters are advanced into the iliac occlusion, while retrograde devices are advanced transfemorally. The transradial and transfemoral channels communicate, allowing the devices to cross the occlusion into the true lumen (radial-femoral antegrade-retrograde rendezvous).

  6. Endoscopic ultrasound rendezvous for bile duct access using a transduodenal approach: cumulative experience at a single center. A case series.

    Science.gov (United States)

    Kim, Y S; Gupta, K; Mallery, S; Li, R; Kinney, T; Freeman, M L

    2010-06-01

    Endoscopic ultrasound (EUS)-assisted biliary access is utilized when conventional endoscopic retrograde cholangiopancreatography (ERCP) fails. We report a 10-year experience utilizing a transduodenal EUS rendezvous via a transpapillary route without dilation of the transduodenal tract, followed by immediate ERCP access. Patients included all EUS-guided rendezvous procedures for biliary access that were performed following ERCP failure. EUS-assisted bile duct puncture was performed via a transduodenal approach and a guide wire was advanced through the papilla without any dilation or bougienage of the tract; ERCP was performed immediately afterwards. EUS-assisted biliary rendezvous was attempted in 15 patients (mean age 66 +/- 18.2 years; malignant = 10, benign = 5). Mean diameter of measured bile ducts was 14.3 +/- 5.17 mm (range 4-23 mm). The reasons for initial ERCP failure were tumor infiltration or edema (n = 9), intradiverticular papilla (n = 2), pre-existing duodenal stent (n = 1), and anatomic anomalies (n = 3). Successful EUS-guided bile duct puncture and wire passage were achieved in all 15 patients (100 %), with drainage being successful in 12 / 15 (80 %). Failures occurred in three patients due to inability to traverse the biliary stricture (n = 2) or dissection of a choledochocele with the guide wire (n = 1); all were subsequently drained via percutaneous methods. Stents placed were metallic in eight patients and plastic in four. Complications consisted of moderate pancreatitis after a difficult ERCP attempt in one patient, and bacteremia after percutaneous biliary drainage in another. There were no instances of perforation, extraluminal air or fluid collections. EUS-assisted biliary drainage utilizing a transduodenal rendezvous approach demonstated a high success rate without any complications directly attributable to the EUS access. Advantages over percutaneous biliary and other methods of EUS biliary access include performance under the same

  7. Plowshare radiation protection guidance

    International Nuclear Information System (INIS)

    Parker, H.M.

    1969-01-01

    The recommendations of the ICRP and the NCRP were developed primarily for occupational radiation exposures. They were later modified and applied to non-occupational exposures of populations. These, with appropriate interpretations, can be used to provide Plowshare radiation protection guidance. Exposures from Plowshare operations will tend to be acute, arising from radionuclides of relatively short half-life, but will have some chronic aspects due to small amounts of long-lived radionuclides generated. In addition, the neutron activation process of Plowshare technology will produce radionuclides not commonly encountered in routine nuclear energy programs. How these radionuclides contribute to personnel exposure is known for only a few situations that may not be representative of Plowshare exposure. Further complications arise from differences in radionuclide deposition and physiological sensitivity among individuals of different ages and states of health in the exposed population. All parameters necessary to evaluate such exposures are not available, even for good quantitative approximations, resulting in the need for interpretive experience. (author)

  8. Plowshare radiation protection guidance

    Energy Technology Data Exchange (ETDEWEB)

    Parker, H M [Environmental and Life Sciences Division, Battelle Memorial Institute, Pacific Northwest Laboratory, Richland, WA (United States)

    1969-07-01

    The recommendations of the ICRP and the NCRP were developed primarily for occupational radiation exposures. They were later modified and applied to non-occupational exposures of populations. These, with appropriate interpretations, can be used to provide Plowshare radiation protection guidance. Exposures from Plowshare operations will tend to be acute, arising from radionuclides of relatively short half-life, but will have some chronic aspects due to small amounts of long-lived radionuclides generated. In addition, the neutron activation process of Plowshare technology will produce radionuclides not commonly encountered in routine nuclear energy programs. How these radionuclides contribute to personnel exposure is known for only a few situations that may not be representative of Plowshare exposure. Further complications arise from differences in radionuclide deposition and physiological sensitivity among individuals of different ages and states of health in the exposed population. All parameters necessary to evaluate such exposures are not available, even for good quantitative approximations, resulting in the need for interpretive experience. (author)

  9. Development of a prediction model for child maltreatment recurrence in Japan: A historical cohort study using data from a Child Guidance Center.

    Science.gov (United States)

    Horikawa, Hiroyuki; Suguimoto, S Pilar; Musumari, Patou Masika; Techasrivichien, Teeranee; Ono-Kihara, Masako; Kihara, Masahiro

    2016-09-01

    To develop a prediction model for the first recurrence of child maltreatment within the first year after the initial report, we carried out a historical cohort study using administrative data from 716 incident cases of child maltreatment (physical abuse, psychological abuse, or neglect) not receiving support services, reported between April 1, 1996 through March 31, 2011 to Shiga Central Child Guidance Center, Japan. In total, 23 items related to characteristics of the child, the maltreatment, the offender, household, and other related factors were selected as predictive variables and analyzed by multivariate logistic regression model for association with first recurrence of maltreatment. According to the stepwise selection procedure six factors were identified that include 9-13year age of child (AOR=3.43/95%CI=1.52-7.72), maltreatment during childhood (AOR=2.56/95%CI=1.31-4.99), household financial instability or poverty (AOR=1.64/95%CI=1.10-2.45), absence of someone in the community who could watch over the child (AOR=1.68/95%CI=1.16-2.44), and the organization as the referral source (AOR=2.21/95%CI=1.24-3.93). Using these six predictors, we generated a linear prediction model with a sensitivity and specificity of 45.2% and 82.4%, respectively. The model may be useful to assess the risk of further maltreatment and help the child and family welfare administrations to develop preventive strategies for recurrence. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  10. Design of guidance laws for lunar pinpoint soft landing

    NARCIS (Netherlands)

    Guo, J.; Han, C.

    2009-01-01

    Future lunar missions ask for the capability to perform precise Guidance, Navigation and Control (GNC) to the selected landing sites on the lunar surface. This paper studies the guidance issues for the lunar pinpoint soft landing problem. The primary contribution of this paper is the design of

  11. 76 FR 75771 - Emergency Planning Guidance for Nuclear Power Plants

    Science.gov (United States)

    2011-12-05

    ... Guidance for Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION: Issuance of NUREG... Support of Nuclear Power Plants;'' NSIR/DPR-ISG-01, ``Interim Staff Guidance Emergency Planning for Nuclear Power Plants;'' and NUREG/CR-7002, ``Criteria for Development of Evacuation Time Estimate Studies...

  12. Factors affecting guidance and counseling programme in primary ...

    African Journals Online (AJOL)

    The objective of this study was to establish the factors that affect guidance and counseling in primary schools. Guidance and counseling seems not to be adequately helping pupils with physical and psychological problems in Nairobi province of Kenya. Many primary schools are faced with indiscipline and poor performance ...

  13. Students' perception of guidance and counselling services offered in ...

    African Journals Online (AJOL)

    Many students of tertiary institutions including Colleges of Education are young adults who feel more concerned about getting a job, making a home and continuing higher education. These concerns require proper guidance The general purpose of this study therefore was to find out the perception of students on guidance ...

  14. General RMP Guidance - Appendix D: OSHA Guidance on PSM

    Science.gov (United States)

    OSHA's Process Safety Management (PSM) Guidance on providing complete and accurate written information concerning process chemicals, process technology, and process equipment; including process hazard analysis and material safety data sheets.

  15. CAREER GUIDANCE EXPERIENCE ABROAD

    Directory of Open Access Journals (Sweden)

    Sergey N. Tolstoguzov

    2015-01-01

    Full Text Available The aim of this paper is to describe the experience of careeroriented activities carried out with students of schools in developed and developing countries. Career Guidance in Russia, despite the vast experience of its implementation, is experiencing serious difficulties. In this regard, it is important to take into account the international experience career-oriented activities, such as in the developed countries of North America and the European Union as well as in several Asian countries with rapidly growing economies and a large demographic potential, taking into account the best variants for the Russian education system. Methods. The experience of career-oriented work undertaken with pupils of the USA, Canada, Israel, France, UK, Germany, Denmark, Sweden, Japan, Singapore, China and India is shown on the basis of the comparative analysis of different publications and information sources. The author has made an attempt to generalize the principles of psycho-pedagogical and administrative assistance in professional self-determination of senior pupils abroad. Scientific novelty. The approaches to career-oriented activities in countries with different levels of economic development are compared for the first time. Some principles are revealed. Firstly, the higher the income level per capita in the country, the greater attention is given to vocational guidance. The politics in the developed countries is based on interests of the individual: children’s acquaintance with the world of professions begins already at younger school and the moment of definitive selfdetermination is postponed till the end of their senior stage of education; the possibility of direction change of professional preparation in case of detection of discrepancy of qualities of the pupil to originally selected profile is provided. Career-oriented activity in developing countries, on the contrary, is rigidly coordinated to requirements of economy and a labour market

  16. RH Packaging Program Guidance

    International Nuclear Information System (INIS)

    Washington TRU Solutions, LLC

    2003-01-01

    The purpose of this program guidance document is to provide technical requirements for use, operation, inspection, and maintenance of the RH-TRU 72-B Waste Shipping Package and directly related components. This document complies with the requirements as specified in the RH-TRU 72-B Safety Analysis Report for Packaging (SARP), and Nuclear Regulatory Commission (NRC) Certificate of Compliance (C of C) 9212. If there is a conflict between this document and the SARP and/or C of C, the SARP and/or C of C shall govern. The C of C states: ''...each package must be prepared for shipment and operated in accordance with the procedures described in Chapter 7.0, ''Operating Procedures,'' of the application.'' It further states: ''...each package must be tested and maintained in accordance with the procedures described in Chapter 8.0, ''Acceptance Tests and Maintenance Program of the Application.'' Chapter 9.0 of the SARP tasks the Waste Isolation Pilot Plant (WIPP) Management and Operating (M and O) contractor with assuring the packaging is used in accordance with the requirements of the C of C. Because the packaging is NRC approved, users need to be familiar with 10 CFR (section) 71.11, ''Deliberate Misconduct.'' Any time a user suspects or has indications that the conditions of approval in the C of C were not met, the Carlsbad Field Office (CBFO) shall be notified immediately. CBFO will evaluate the issue and notify the NRC if required. This document details the instructions to be followed to operate, maintain, and test the RH-TRU 72-B packaging. This Program Guidance standardizes instructions for all users. Users shall follow these instructions. Following these instructions assures that operations are safe and meet the requirements of the SARP. This document is available on the Internet at: ttp://www.ws/library/t2omi/t2omi.htm. Users are responsible for ensuring they are using the current revision and change notices. Sites may prepare their own document using the word

  17. The continuum of behavior guidance.

    Science.gov (United States)

    Nelson, Travis

    2013-01-01

    Behavior guidance is a continuum of techniques, basic and advanced, fundamental to the provision of quality dental care for pediatric patients. This practice must be individualized, pairing the correct method of behavior guidance with each child. To select the appropriate technique, the clinician must have a thorough understanding of each aspect of the continuum and anticipate parental expectations, child temperament, and the technical procedures necessary to complete care. By effectively using techniques within the continuum of behavior guidance, a healing relationship with the family is maintained while addressing dental disease and empowering the child to receive dental treatment throughout their lifetime. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Regulatory guidance for license renewal

    International Nuclear Information System (INIS)

    Thoma, John A.

    1991-01-01

    The proposed 10 CFR Part 54 rule proceduralizes the process for license renewal by identifying both the administrative and technical requirements for a renewal application. To amplify and support this regulation, written guidance has been provided in the form of a draft Regulatory Guide (DG 1009) and a draft Standard Review Plan for License Renewal (NUREG 1299). This guidance is scheduled to be finalized in 1992. Similar guidance will be provided for the proposed revisions to 10 CFR Part 51 concerning the environmental aspects of license renewal. (author)

  19. An Investigation of the Guidance Counselling Needs of Adults with Dyslexia in the Adult Educational Guidance Initiative (AEGI)

    Science.gov (United States)

    Elftorp, Petra; Hearne, Lucy

    2014-01-01

    The experiences of adult learners with dyslexia is an under-researched area in Ireland at present. This article will discuss the findings from phase one of a mixed methods research study, which is investigating the guidance counselling needs of clients with dyslexia within the Adult Education Guidance Initiative (AEGI). The research is underpinned…

  20. Navigation Strategies for Primitive Solar System Body Rendezvous and Proximity Operations

    Science.gov (United States)

    Getzandanner, Kenneth M.

    2011-01-01

    A wealth of scientific knowledge regarding the composition and evolution of the solar system can be gained through reconnaissance missions to primitive solar system bodies. This paper presents analysis of a baseline navigation strategy designed to address the unique challenges of primitive body navigation. Linear covariance and Monte Carlo error analysis was performed on a baseline navigation strategy using simulated data from a· design reference mission (DRM). The objective of the DRM is to approach, rendezvous, and maintain a stable orbit about the near-Earth asteroid 4660 Nereus. The outlined navigation strategy and resulting analyses, however, are not necessarily limited to this specific target asteroid as they may he applicable to a diverse range of mission scenarios. The baseline navigation strategy included simulated data from Deep Space Network (DSN) radiometric tracking and optical image processing (OpNav). Results from the linear covariance and Monte Carlo analyses suggest the DRM navigation strategy is sufficient to approach and perform proximity operations in the vicinity of the target asteroid with meter-level accuracy.

  1. Endoscopic dilation of complete oesophageal obstructions with a combined antegrade-retrograde rendezvous technique.

    Science.gov (United States)

    Bertolini, Reto; Meyenberger, Christa; Putora, Paul Martin; Albrecht, Franziska; Broglie, Martina Anja; Stoeckli, Sandro J; Sulz, Michael Christian

    2016-02-21

    To investigate the combined antegrade-retrograde endoscopic rendezvous technique for complete oesophageal obstruction and the swallowing outcome. This single-centre case series includes consecutive patients who were unable to swallow due to complete oesophageal obstruction and underwent combined antegrade-retrograde endoscopic dilation (CARD) within the last 10 years. The patients' demographic characteristics, clinical parameters, endoscopic therapy, adverse events, and outcomes were obtained retrospectively. Technical success was defined as effective restoration of oesophageal patency. Swallowing success was defined as either percutaneous endoscopic gastrostomy (PEG)-tube independency and/or relevant improvement of oral food intake, as assessed by the functional oral intake scale (FOIS) (≥ level 3). The cohort consisted of six patients [five males; mean age 71 years (range, 54-74)]. All but one patient had undergone radiotherapy for head and neck or oesophageal cancer. Technical success was achieved in five out of six patients. After discharge, repeated dilations were performed in all five patients. During follow-up (median 27 mo, range, 2-115), three patients remained PEG-tube dependent. Three of four patients achieved relevant improvement of swallowing (two patients: FOIS 6, one patient: FOIS 7). One patient developed mediastinal emphysema following CARD, without a need for surgery. The CARD technique is safe and a viable alternative to high-risk blind antegrade dilation in patients with complete proximal oesophageal obstruction. Although only half of the patients remained PEG-tube independent, the majority improved their ability to swallow.

  2. Gunshot Injury of Pelvi-Ureteric Junction: Management by the Rendezvous Technique.

    Science.gov (United States)

    Sekhon, Virender; Suryavanshi, Manav

    2017-01-01

    Background: Gunshot injury of ureter is common, but isolated injury of pelvi-ureteric junction (PUJ) has not been reported. Moreover, its management is evolving from the traditional urinary diversion, stenting followed later by definitive surgical repair to a more upfront minimally invasive endourologic approach. Case Presentation: An adolescent boy presented with gunshot laceration injury of left PUJ with associated small intestinal injury. Radiological investigations confirmed a contained urinary leak. Retrograde stenting was not effective. The same guidewire was retained into the urinoma and an antegrade percutaneous access was obtained. A snare was used to retrieve the guidewire and obtain a through and through access. A ureteropelvic drainage catheter was inserted over this guidewire and secured in the upper ureter, bypassing the region of injury. Three weeks later, the drainage tube was removed and the same tract was used for antegrade stenting. A retrograde pyelogram done 3 months later during stent removal demonstrated no leak. The patient is asymptomatic for urinary symptoms on 6 months of follow-up. Conclusion: Rendezvous technique is a feasible alternative to open repair of gunshot pelvi-ureteric junction injury. Long-term follow-up is awaited.

  3. Coherent Doppler lidar for automated space vehicle rendezvous, stationkeeping and capture

    Science.gov (United States)

    Bilbro, James A.

    1991-01-01

    The inherent spatial resolution of laser radar makes ladar or lidar an attractive candidate for Automated Rendezvous and Capture application. Previous applications were based on incoherent lidar techniques, requiring retro-reflectors on the target vehicle. Technology improvements (reduced size, no cryogenic cooling requirement) have greatly enhanced the construction of coherent lidar systems. Coherent lidar permits the acquisition of non-cooperative targets at ranges that are limited by the detection capability rather than by the signal-to-noise ratio (SNR) requirements. The sensor can provide translational state information (range, velocity, and angle) by direct measurement and, when used with any array detector, also can provide attitude information by Doppler imaging techniques. Identification of the target is accomplished by scanning with a high pulse repetition frequency (dependent on the SNR). The system performance is independent of range and should not be constrained by sun angle. An initial effort to characterize a multi-element detection system has resulted in a system that is expected to work to a minimum range of 1 meter. The system size, weight and power requirements are dependent on the operating range; 10 km range requires a diameter of 3 centimeters with overall size at 3 x 3 x 15 to 30 cm, while 100 km range requires a 30 cm diameter.

  4. Maximizing the Lifetime of Wireless Sensor Networks Using Multiple Sets of Rendezvous

    Directory of Open Access Journals (Sweden)

    Bo Li

    2015-01-01

    Full Text Available In wireless sensor networks (WSNs, there is a “crowded center effect” where the energy of nodes located near a data sink drains much faster than other nodes resulting in a short network lifetime. To mitigate the “crowded center effect,” rendezvous points (RPs are used to gather data from other nodes. In order to prolong the lifetime of WSN further, we propose using multiple sets of RPs in turn to average the energy consumption of the RPs. The problem is how to select the multiple sets of RPs and how long to use each set of RPs. An optimal algorithm and a heuristic algorithm are proposed to address this problem. The optimal algorithm is highly complex and only suitable for small scale WSN. The performance of the proposed algorithms is evaluated through simulations. The simulation results indicate that the heuristic algorithm approaches the optimal one and that using multiple RP sets can significantly prolong network lifetime.

  5. Basic targeting strategies for rendezvous and flyby missions to the near-Earth asteroids

    Science.gov (United States)

    Perozzi, Ettore; Rossi, Alessandro; Valsecchi, Giovanni B.

    2001-01-01

    Missions to asteroids and comets are becoming increasingly feasible both from a technical and a financial point of view. In particular, those directed towards the Near-Earth Asteroids have proven suitable for a low-cost approach, thus attracting the major space agencies as well as private companies. The choice of a suitable target involves both scientific relevance and mission design considerations, being often a difficult task to accomplish due to the limited energy budget at disposal. The aim of this paper is to provide an approach to basic trajectory design which allows to account for both aspects of the problem, taking into account scientific and technical information. A global characterization of the Near-Earth Asteroids population carried out on the basis of their dynamics, physical properties and flight dynamics considerations, allows to identify a group of candidates which satisfy both, the scientific and engineering requirements. The feasibility of rendezvous and flyby missions towards them is then discussed and the possibility of repeated encounters with the same object is investigated, as an intermediate scenario. Within this framework, the capability of present and near future launch and propulsion systems for interplanetary missions is also addressed.

  6. An Evaluation of Unemployment Reduction in Akwa Ibom State using Career Guidance and Counselling

    OpenAIRE

    Nsikak-Abasi Udofia; Eno Daniel Inyang

    2013-01-01

    This study was carried out to examine the possibility of reducing unemployment in Akwa Ibom State using career guidance and counselling interventions. To guide the study, four research questions and four null hypotheses were formulated. Variables such as educational guidance, vocational, personality trait guidance and sociological guidance were used in the investigation. A survey design was used in studying a population of 6509 senior secondary two students in 58 public secondary schools that...

  7. SPLC Sustainable Purchasing Guidance Profile

    Science.gov (United States)

    To help you find the resource that is right for your organization, EPA conducted a scan of the landscape and developed summary profiles of some of the leading sources of sustainable purchasing guidance around the globe.

  8. CDM Convective Forecast Planning guidance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The CDM Convective Forecast Planning (CCFP) guidance product provides a foreast of en-route aviation convective hazards. The forecasts are updated every 2 hours and...

  9. Guidance at the educational marketplace

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    in educational policies and institutions. As educational systems have expanded and, further, have been restructured with the expansion of choice opportunities since the 1980s, guidance has become prioritized as a form of counseling or coaching, which can support students. Thus, guidance has become an important...... `agent´ on the educational "market´, assisting (potential) students into and around the `marketplace´. Consequently, guidance is also an important `agent´ for educational institutions that increasingly use marketing strategies to promote themselves on the market to attract and hold on to their “customers......” in order for the institutions to increase their ´market value´, `sales” and “turnover”. Thus, the expansion of guidance is nurtured by the expansion of the logic of marketization and consumerism. Drawing on Foucauldian perspectives in educational research, which highlight the expansion of powerful...

  10. Botulinum Toxin A Injections Into Pelvic Floor Muscles Under Electromyographic Guidance for Women With Refractory High-Tone Pelvic Floor Dysfunction: A 6-Month Prospective Pilot Study.

    Science.gov (United States)

    Morrissey, Darlene; El-Khawand, Dominique; Ginzburg, Natasha; Wehbe, Salim; O'Hare, Peter; Whitmore, Kristene

    2015-01-01

    High-tone pelvic floor dysfunction (HTPFD) is a debilitating chronic pain disorder for many women with significant impact on their quality of life (QoL). Our objective was to determine the efficacy of electromyography-guided onabotulinumtoxinA (Botox; Allergan, Irvine, Calif) injections in treating patient's perception of pelvic pain and improving QoL measurement scores. This is a prospective pilot open-label study of women with chronic pelvic pain and HTPFD who have failed conventional therapy between January 2011 and August 2013. Botox injections (up to 300 U) were done using needle electromyography guidance, from a transperineal approach, to localize spastic pelvic floor muscles (PFMs). Data were collected at baseline, 4, 8, 12, and 24 weeks after injections. This included demographics; Visual Analog Scale (VAS) scores for pain and dyspareunia; validated questionnaires for symptoms, QoL, and sexual function; Global Response Assessment scale for pelvic pain; digital examination of PFM for tone and tenderness; and vaginal manometry. Side effects were also recorded. Out of 28 women who enrolled in the study, 21 completed the 6-month follow-up and qualified for analysis. The mean (SD) age was 35.1 (9.4) years (range, 22-50 years), and the mean (SD) body mass index was 25 (4.4). Comorbidities included interstitial cystitis/bladder pain syndrome (42.9%) and vulvodynia (66.7%). Overall, 61.9% of subjects reported improvement on Global Response Assessment at 4 weeks and 80.9% at 8, 12, and 24 weeks post injection, compared with baseline. Of the subjects who were sexually active at baseline, 58.8% (10/17), 68.8% (11/16), 80% (12/15), and 83.3% (15/18) reported less dyspareunia at 4, 8, 12, and 24 weeks, respectively. Dyspareunia Visual Analog Scale score significantly improved at weeks 12 (5.6, P = 0.011) and 24 (5.4, P = 0.004) compared with baseline (7.8). Two of the 4 patients who avoided sexual activity at baseline secondary to dyspareunia resumed and tolerated

  11. [Anterior guidance in complete dentures].

    Science.gov (United States)

    Dubreuil, J; Trevelo, A

    1990-01-01

    Although the anterior guidance in complete dentures is not really a guide, the arrangement of the anterior maxillary and mandibular prosthetic teeth, defines a propulsive line called the virtual anterior guidance, a part from the cinematic criterias. The influence of this guide on cuspal movement is superior, in all mandibular points, to the influence of the condylar pathway. If this line is not respected, the practitioner may have to do excessive grindings during occlusal adjustments.

  12. Apply an Augmented Reality in a Mobile Guidance to Increase Sense of Place for Heritage Places

    Science.gov (United States)

    Chang, Yu-Lien; Hou, Huei-Tse; Pan, Chao-Yang; Sung, Yao-Ting; Chang, Kuo-En

    2015-01-01

    Based on the sense of place theory and the design principles of guidance and interpretation, this study developed an augmented reality mobile guidance system that used a historical geo-context-embedded visiting strategy. This tool for heritage guidance and educational activities enhanced visitor sense of place. This study consisted of 3 visitor…

  13. Contextual cueing improves attentional guidance, even when guidance is supposedly optimal.

    Science.gov (United States)

    Harris, Anthony M; Remington, Roger W

    2017-05-01

    Visual search through previously encountered contexts typically produces reduced reaction times compared with search through novel contexts. This contextual cueing benefit is well established, but there is debate regarding its underlying mechanisms. Eye-tracking studies have consistently shown reduced number of fixations with repetition, supporting improvements in attentional guidance as the source of contextual cueing. However, contextual cueing benefits have been shown in conditions in which attentional guidance should already be optimal-namely, when attention is captured to the target location by an abrupt onset, or under pop-out conditions. These results have been used to argue for a response-related account of contextual cueing. Here, we combine eye tracking with response time to examine the mechanisms behind contextual cueing in spatially cued and pop-out conditions. Three experiments find consistent response time benefits with repetition, which appear to be driven almost entirely by a reduction in number of fixations, supporting improved attentional guidance as the mechanism behind contextual cueing. No differences were observed in the time between fixating the target and responding-our proxy for response related processes. Furthermore, the correlation between contextual cueing magnitude and the reduction in number of fixations on repeated contexts approaches 1. These results argue strongly that attentional guidance is facilitated by familiar search contexts, even when guidance is near-optimal. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  14. Hybrid Guidance System for Relative Navigation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Automated Rendezvous and Capture (AR&C) is a critical United States technology gap. AR&C is identified as a critical enabling technology for future NASA...

  15. Trojan Tour and Rendezvous (TTR): A New Frontiers Mission to Explore the Origin and Evolution of the Early Solar System

    Science.gov (United States)

    Bell, J. F., III; Olkin, C.; Castillo, J. C.

    2015-12-01

    The orbital properties, compositions, and physical properties of the diverse populations of small outer solar system bodies provide a forensic map of how our solar system formed and evolved. Perhaps the most potentially diagnostic, but least explored, of those populations are the Jupiter Trojan asteroids, which orbit at ~5 AU in the L4 and L5 Lagrange points of Jupiter. More than 6200 Jupiter Trojans are presently known, but these are predicted to be only a small fraction of the 500,000 to 1 million Trojans >1 km in size. The Trojans are hypothesized to be either former Kuiper Belt Objects (KBOs) that were scattered into the inner solar system by early giant planet migration and then trapped in the 1:1 Jupiter mean motion resonance, or bodies formed near 5 AU in a much more quiescent early solar system, and then trapped at L4 and L5. The 2011 Planetary Science Decadal Survey identified important questions about the origin and evolution of the solar system that can be addressed by studying of the Trojan asteroids, including: (a) How did the giant planets and their satellite systems accrete, and is there evidence that they migrated to new orbital positions? (b) What is the relationship between large and small KBOs? Is the small population derived by impact disruption of the large one? (c) What kinds of surface evolution, radiation chemistry, and surface-atmosphere interactions occur on distant icy primitive bodies? And (d) What are the sources of asteroid groups (Trojans and Centaurs) that remain to be explored by spacecraft? The Trojan Tour and Rendezvous (TTR) is a New Frontiers-class mission designed to answer these questions, and to test hypotheses for early giant planet migration and solar system evolution. Via close flybys of a large number of these objects,, and orbital characterization of at least one large Trojan, TTR will enable the first-time exploration of this population. Our primary mission goals are to characterize the overall surface geology

  16. Usefulness of the rendezvous technique for biliary stricture after adult right-lobe living-donor liver transplantation with duct-to-duct anastomosis.

    Science.gov (United States)

    Chang, Jae Hyuck; Lee, In Seok; Chun, Ho Jong; Choi, Jong Young; Yoon, Seung Kyoo; Kim, Dong Goo; You, Young Kyoung; Choi, Myung-Gyu; Choi, Kyu-Yong; Chung, In-Sik

    2010-03-01

    Replacement of a percutaneous transhepatic biliary drainage (PTBD) catheter with inside stents using endoscopic retrograde cholangiography is difficult in patients with angulated or twisted biliary anastomotic stricture after living donor liver transplantation (LDLT). We evaluated the usefulness and safety of the rendezvous technique for the management of biliary stricture after LDLT. Twenty patients with PTBD because of biliary stricture after LDLT with duct-to-duct anastomosis underwent the placement of inside stents using the rendezvous technique. Inside stents were successfully placed in the 20 patients using the rendezvous technique. The median procedure time was 29.6 (range, 7.5-71.8) minutes. The number of inside stents placed was one in 12 patients and two in eight patients. One mild acute pancreatitis and one acute cholangitis occurred, which improved within a few days. Inside stent related sludge or stone was identified in 12 patients during follow-up. Thirteen patients achieved stent-free status for a median of 281 (range, 70-1,351) days after removal of the inside stents. The rendezvous technique is a useful and safe method for the replacement of PTBD catheter with inside stent in patients with biliary stricture after LDLT with duct-to-duct anastomosis. The rendezvous technique could be recommended to patients with angulated or twisted strictures.

  17. Quality in career guidance: The Danish case

    DEFF Research Database (Denmark)

    Plant, Peter

    2011-01-01

    Quality assurance systems are introduced in career guidance to monitor, control and develop guidance interventions. The Danish case represents at centrally driven, top-down approach......Quality assurance systems are introduced in career guidance to monitor, control and develop guidance interventions. The Danish case represents at centrally driven, top-down approach...

  18. Surgery in biliary lithiasis: from the traditional "open" approach to laparoscopy and the "rendezvous" technique.

    Science.gov (United States)

    Tarantino, Giuseppe; Magistri, Paolo; Ballarin, Roberto; Assirati, Giacomo; Di Cataldo, Antonio; Di Benedetto, Fabrizio

    2017-12-15

    According to the current literature, biliary lithiasis is a worldwide-diffused condition that affects almost 20% of the general population. The rate of common bile duct stones (CBDS) in patients with symptomatic cholelithiasis is estimated to be 10% to 33%, depending on patient's age. Compared to stones in the gallbladder, the natural history of secondary CBDS is still not completely understood. It is not clear whether an asymptomatic choledocholithiasis requires treatment or not. For many years, open cholecystectomy with choledochotomy and/or surgical sphincterotomy and cleaning of the bile duct were the gold standard to treat both pathologies. Development of both endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic surgery, together with improvements in diagnostic procedures, influenced new approaches to the management of CBDS in association with gallstones. We decided to systematically review the literature in order to identify all the current therapeutic options for CBDS. A systematic literature search was performed independently by two authors using PubMed, EMBASE, Scopus and the Cochrane Library Central. The therapeutic approach nowadays varies greatly according to the availability of experience and expertise in each center, and includes open or laparoscopic common bile duct exploration, various combinations of laparoscopic cholecystectomy and ERCP and combined laparoendoscopic rendezvous. Although ERCP followed by laparoscopic cholecystectomy is currently preferred in the majority of hospitals worldwide, the optimal treatment for concomitant gallstones and CBDS is still under debate, and greatly varies among different centers. Copyright © 2017 The Editorial Board of Hepatobiliary & Pancreatic Diseases International. Published by Elsevier B.V. All rights reserved.

  19. Comparison of transhepatic and extrahepatic routes for EUS-guided rendezvous procedure for distal CBD obstruction.

    Science.gov (United States)

    Dhir, Vinay; Bhandari, Suryaprakash; Bapat, Mukta; Joshi, Nitin; Vivekanandarajah, Suhirdan; Maydeo, Amit

    2013-04-01

    EUS-guided rendezvous procedure (EUS-RV) can be done by the transhepatic (TH) or the extrahepatic (EH) route. There is no data on the preferred access route when both routes are available. To compare the success, complications, and duration of hospitalization for patients undergoing EUS-RV by the TH or the EH route. Patients with distal common bile duct (CBD) obstruction, who failed selective cannulation, underwent EUS-RV by the TH route through the stomach or the EH route through the duodenum. A total of 35 patients were analysed (17 TH, 18 EH). The mean procedure time was significantly longer for the TH group (34.4 vs. 25.7 min; p = 0.0004). There was no difference in the technical success (94.1 vs. 100%). However, the TH group had a higher incidence of post-procedure pain (44.1 vs. 5.5%; p = 0.017), bile leak (11.7 vs. 0; p = 0.228), and air under diaphragm (11.7 vs. 0; p = 0.228). All bile leaks were small and managed conservatively. Duration of hospitalization was significantly higher for the TH group (2.52 vs. 0.17 days; p = 0.015). EUS-RV has similar success rate by the TH or the EH route. However, the TH route has higher post-procedure pain, longer procedure time, and longer duration of hospitalization. The EH route should be preferred for EUS-RV in patients with distal CBD obstruction when both access routes are technically feasible.

  20. Coherent Doppler lidar for automated space vehicle, rendezvous, station-keeping and capture

    Science.gov (United States)

    Dunkin, James A.

    1991-01-01

    Recent advances in eye-safe, short wavelength solid-state lasers offer real potential for the development of compact, reliable, light-weight, efficient coherent lidar. Laser diode pumping of these devices has been demonstrated, thereby eliminating the need for flash lamp pumping, which has been a major drawback to the use of these lasers in space based applications. Also these lasers now have the frequency stability required to make them useful in coherent lidar, which offers all of the advantages of non-coherent lidar, but with the additional advantage that direct determination of target velocity is possible by measurement of the Doppler shift. By combining the Doppler velocity measurement capability with the inherent high angular resolution and range accuracy of lidar it is possible to construct Doppler images of targets for target motion assessment. A coherent lidar based on a Tm,Ho:YAG 2-micrometer wavelength laser was constructed and successfully field tested on atmospheric targets in 1990. This lidar incorporated an all solid state (laser diode pumped) master oscillator, in conjunction with a flash lamp pumped slave oscillator. Solid-state laser technology is rapidly advancing, and with the advent of high efficiency, high power, semiconductor laser diodes as pump sources, all-solid-state, coherent lidars are a real possibility in the near future. MSFC currently has a feasibility demonstration effort under way which will involve component testing, and preliminary design of an all-solid-state, coherent lidar for automatic rendezvous, and capture. This two year effort, funded by the Director's Discretionary Fund is due for completion in 1992.

  1. Rendezvous with Toutatis from the Moon: The Chang'e-2 mission

    Science.gov (United States)

    Huang, J.; Tang, X.; Meng, L.

    2014-07-01

    Chang'e-2 probe was the second lunar probe of China, with the main objectives to demonstrate some key features of the new lunar soft landing technology, and its applications to future exploration missions. After completing the planned mission successfully, Chang'e-2 flew away from the Moon and entered into the interplanetary space. Later, at a distance of 7 million km from the Earth, Chang'e-2 encountered asteroid (4179) Toutatis with a very close fly-by distance and obtained colorful images with a 3-m resolution. Given some surplus velocity increment as well as the promotion of autonomous flight ability and improvement of control, propulsion, and thermal systems in the initial design, Chang'e-2 had the capabilities necessary for escaping from the Moon. By taking advantage of the unique features of the Lagrangian point, the first close fly-by of asteroid Toutatis was realized despite the tight constraints of propellant allocation, spacecraft-Earth communication, and coordination of execution sequences. Chang'e-2 realized the Toutatis flyby with a km-level distance at closest approach. In the absence of direct measurement method, based on the principle of relative navigation and through the use of the sequence of target images, we calculated the rendezvous parameters such as relative distance and image resolution. With the help of these parameters, some fine and new scientific discoveries about the asteroid were obtained by techniques of optical measurements and image processing. Starting with an innovative design, followed by high-fidelity testing and demonstration, elaborative implementation, and optimal usage of residual propellant, Chang'e-2 has for the first time successfully explored the Moon, L2 point and an asteroid, while achieving the purpose of 'faster, better, cheaper'. What Chang'e-2 has accomplished was far beyond our expectations. *J. Huang is the chief designer (PI) of Chang'e-2 probe, planned Chang'e-2's multi-objective and multitasking exploration

  2. Becoming a Guidance Counsellor in Ontario: Formative Influences from Counsellors' Perspective

    Science.gov (United States)

    Nadon, Daniel; Samson, André; Gazzola, Nicola; Thériault, Anne

    2016-01-01

    Contrary to guidance counsellors elsewhere in North America who hold a master's degree, career and guidance counselling services in secondary schools in Ontario are delivered by teachers who have completed additional undergraduate studies. Guidance counsellors are pivotal components of the school as they complete tasks that promote students'…

  3. Endoscopic ultrasonography-guided pancreatic duct access: techniques and literature review of pancreatography, transmural drainage and rendezvous techniques.

    Science.gov (United States)

    Itoi, Takao; Kasuya, Kazuhiko; Sofuni, Atsushi; Itokawa, Fumihide; Kurihara, Toshio; Yasuda, Ichiro; Nakai, Yousuke; Isayama, Hiroyuki; Moriyasu, Fuminori

    2013-05-01

    Endoscopic ultrasonography-guided (EUS)-guided pancreatic interventions have gained increasing attention. Here we review EUS-guided pancreatic duct (PD) access techniques and outcomes. EUS-guided PD intervention is divided into two types, antegrade and rendezvous techniques, following EUS-guided pancreatography. In the antegrade technique, pancreaticoenterostomy is carried out by stent placement between the PD and the stomach, duodenum, or jejunum. Transenteric antegrade PD stenting is conducted by stent placement, advancing anteriorly into the PD through the pancreatic tract. The rendezvous technique is carried out by using a guidewire through the papilla or anastomotic site for retrograde stent insertion. In terms of EUS-guided PD stenting, 11 case reports totaling 75 patients (35 normal anatomy, 40 altered anatomy) have been published. The technical success rate was greater than 70%. Early adverse events, including severe hematoma and severe pancreatitis,occurred in seven (63.6%) of 11 reports. Regarding the rendezvous technique, 12 case reports totaling 52 patients (22 normal anatomy, 30 altered anatomy) have been published. The technical success rate ranged from 25% to 100%. It was 48% in one report that involved more than 20 cases. Once stents were placed, all patients became free of symptoms. Early mild adverse events occurred in four (36.4%) of 11 reports. In conclusion, although it can be risky because of possible serious or even fatal adverse events, including pancreatic juice leakage, perforation and severe acute pancreatitis, EUS-PD access seems to be promising for treating symptomatic pancreatic diseases caused by PD stricture and pancreaticoenterostomy stricture. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  4. Information architecture. Volume 3: Guidance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    The purpose of this document, as presented in Volume 1, The Foundations, is to assist the Department of Energy (DOE) in developing and promulgating information architecture guidance. This guidance is aimed at increasing the development of information architecture as a Departmentwide management best practice. This document describes departmental information architecture principles and minimum design characteristics for systems and infrastructures within the DOE Information Architecture Conceptual Model, and establishes a Departmentwide standards-based architecture program. The publication of this document fulfills the commitment to address guiding principles, promote standard architectural practices, and provide technical guidance. This document guides the transition from the baseline or defacto Departmental architecture through approved information management program plans and budgets to the future vision architecture. This document also represents another major step toward establishing a well-organized, logical foundation for the DOE information architecture.

  5. Dissecting Attending Surgeons' Operating Room Guidance: Factors That Affect Guidance Decision Making.

    Science.gov (United States)

    Chen, Xiaodong Phoenix; Williams, Reed G; Smink, Douglas S

    2015-01-01

    The amount of guidance provided by the attending surgeon in the operating room (OR) is a key element in developing residents' autonomy. The purpose of this study is to explore factors that affect attending surgeons' decision making regarding OR guidance provided to the resident. We used video-stimulated recall interviews (VSRI) throughout this 2-phase study. In Phase 1, 3 attending surgeons were invited to review separately 30 to 45 minute video segments of their prerecorded surgical operations to explore factors that influenced their OR guidance decision making. In Phase 2, 3 attending surgeons were observed and documented in the OR (4 operations, 341min). Each operating surgeon reviewed their videotaped surgical performance within 5 days of the operation to reflect on factors that affected their decision making during the targeted guidance events. All VSRI were recorded. Thematic analysis and manual coding were used to synthesize and analyze data from VSRI transcripts, OR observation documents, and field notes. A total of 255 minutes of VSRI involving 6 surgeons and 7 surgical operations from 5 different procedures were conducted. A total of 13 guidance decision-making influence factors from 4 categories were identified (Cohen's κ = 0.674): Setting (case schedule and patient morbidity), content (procedure attributes and case progress), resident (current competency level, trustworthiness, self-confidence, and personal traits), and attending surgeon (level of experience, level of comfort, preferred surgical technique, OR training philosophy, and responsibility as surgeon). A total of 5 factors (case schedule, patient morbidity, procedure attributes, resident current competency level, and trustworthiness) influenced attending surgeons' pre-OR guidance plans. "OR training philosophy" and "responsibility as surgeon" were anchor factors that affected attending surgeons' OR guidance decision-making patterns. Surgeons' OR guidance decision making is a dynamic process

  6. Combined radiologic and endoscopic treatment (using the “rendezvous technique”) of a biliary fistula following left hepatectomy

    Science.gov (United States)

    Gracient, Aurélien; Rebibo, Lionel; Delcenserie, Richard; Yzet, Thierry; Regimbeau, Jean-Marc

    2016-01-01

    Despite the ongoing decrease in the frequency of complications after hepatectomy, biliary fistulas still occur and are associated with high morbidity and mortality rates. Here, we report on an unusual technique for managing biliary fistula following left hepatectomy in a patient in whom the right posterior segmental duct joined the left hepatic duct. The biliary fistula was treated with a combined radiologic and endoscopic procedure based on the “rendezvous technique”. The clinical outcome was good, and reoperation was not required. PMID:27570431

  7. Computed tomography guidance for skeletal biopsy

    International Nuclear Information System (INIS)

    Frager, D.H.; Goldman, M.J.; Elkin, C.M.; Cynamon, J.; Leeds, N.E.; Seimon, L.P.; Habermann, E.T.; Schreiber, K.; Freeman, L.M.

    1987-01-01

    Computed tomographic (CT) guided biopsy and abscess drainage of multiple organ systems have been well described. Reports of spinal and skeletal applications have been less common. This study describes the use of CT guidance in the biopsy of various skeletal lesions in 46 patients. Forty-one patients had skinny needle aspirations (18 or 22 gauge) and 23 patients had trephine core biopsies. Sites of the lesions included: thoracic spine - 15 patients, lumbosacral spine - 17 patients, bony pelvis - 6 patients, rib - 2 patients, and long bones - 6 patients. Fast scanners capable of rapid image reconstruction have overcome many constraints. With CT guidance, the physician who performs the procedure receives virtually no ionizing radiation. The exact location of the needle tip is accurately visualized in relation to the lesion being biopsied and to the vital organs. (orig.)

  8. Evaluation Of Career Guidance Program In Vocational High School

    Directory of Open Access Journals (Sweden)

    Martaningsih Sri Tutur

    2018-01-01

    This review of career guidance program evaluation is conducted qualitatively through surveys, interviews and leiterature studies to provide an overview of evaluation program and its relevance to the necessity. Understanding the quality, weaknesses, obstacles to service implementation, and potential utilization are expected to improve career guidance effectiveness services in vocational high school. An evaluation on the overall career guidance program, will provide feedback for ongoing improvement. Various evaluation models are available, it needs to be selected about the relevance to the career counseling program characteristics, so that evaluation feedback is more optimal.

  9. Strapdown Homing Guidance System Design for Some Ammunition

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The strapdown homing guidance system for some ammunition was mainly studied. A strong tracking Kalman filter was designed for the strapdown homing guidance system using the information measured by the strapdown homing seeker to estimate relative movement variables between the ammunition and target. Then the optimal proportional law, which using the estimated information, guided the ammunition. Simulation results show that the designed strapdown homing guidance system with strong tracking Kalman filter can attack the maneuvering target effectively, and satisfy the performance index for the guided ammunition system.

  10. The rendezvous technique involving insertion of a guidewire in a percutaneous transhepatic gallbladder drainage tube for biliary access in a case of difficult biliary cannulation.

    Science.gov (United States)

    Sunada, Fumiko; Morimoto, Naoki; Tsukui, Mamiko; Kurata, Hidekazu

    2017-05-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic method and treatment approach for biliary diseases. However, biliary cannulation can be difficult in some cases. We performed ERCP in a 97-year-old woman with abdominal pain resulting from acute cholangitis caused by choledocholithiasis and observed difficult biliary cannulation. Eventually, the patient was successfully treated with the rendezvous technique. We could not cannulate the biliary duct during ERCP twice. Therefore, we placed a percutaneous transhepatic gallbladder drainage (PTGBD) tube without intrahepatic dilation. The rendezvous technique was performed using the PTGBD tube. The patient did not experience pancreatitis or perforation.

  11. DOE Waste Treatability Group Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, T.D.

    1995-01-01

    This guidance presents a method and definitions for aggregating U.S. Department of Energy (DOE) waste into streams and treatability groups based on characteristic parameters that influence waste management technology needs. Adaptable to all DOE waste types (i.e., radioactive waste, hazardous waste, mixed waste, sanitary waste), the guidance establishes categories and definitions that reflect variations within the radiological, matrix (e.g., bulk physical/chemical form), and regulated contaminant characteristics of DOE waste. Beginning at the waste container level, the guidance presents a logical approach to implementing the characteristic parameter categories as part of the basis for defining waste streams and as the sole basis for assigning streams to treatability groups. Implementation of this guidance at each DOE site will facilitate the development of technically defined, site-specific waste stream data sets to support waste management planning and reporting activities. Consistent implementation at all of the sites will enable aggregation of the site-specific waste stream data sets into comparable national data sets to support these activities at a DOE complex-wide level.

  12. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    of the project were not previously considered. We define a special inseparable cost function and develop a solution complex capable of using this cost function. In relation to calibration and estimation of statistical models used for dynamic route guidance we worked with generating random number sequences...

  13. Consensus standard requirements and guidance

    International Nuclear Information System (INIS)

    Putman, V.L.

    1995-01-01

    This report presents information from the ANS Criticality Alarm System Workshop relating to the consensus standard requirements and guidance. Topics presented include: definition; nomenclature; requirements and recommendations; purpose of criticality alarms; design criteria; signal characteristics; reliability, dependability and durability; tests; and emergency preparedness and planning

  14. DOE Waste Treatability Group Guidance

    International Nuclear Information System (INIS)

    Kirkpatrick, T.D.

    1995-01-01

    This guidance presents a method and definitions for aggregating U.S. Department of Energy (DOE) waste into streams and treatability groups based on characteristic parameters that influence waste management technology needs. Adaptable to all DOE waste types (i.e., radioactive waste, hazardous waste, mixed waste, sanitary waste), the guidance establishes categories and definitions that reflect variations within the radiological, matrix (e.g., bulk physical/chemical form), and regulated contaminant characteristics of DOE waste. Beginning at the waste container level, the guidance presents a logical approach to implementing the characteristic parameter categories as part of the basis for defining waste streams and as the sole basis for assigning streams to treatability groups. Implementation of this guidance at each DOE site will facilitate the development of technically defined, site-specific waste stream data sets to support waste management planning and reporting activities. Consistent implementation at all of the sites will enable aggregation of the site-specific waste stream data sets into comparable national data sets to support these activities at a DOE complex-wide level

  15. A Customized Online Nutrition Guidance System Is Effective for Treating Patients with Nonalcoholic Fatty Liver Disease by Supporting Continuity of Diet Therapy at Home: A Pilot Study

    Science.gov (United States)

    Aoyama, Tomonori; Takada, Hidekatsu; Uchiyama, Akira; Kon, Kazuyoshi; Yamashina, Shunhei; Ikejima, Kenichi; Ban, Hideyuki; Watanabe, Sumio

    2017-01-01

    Continuity is required for diet therapy, but it depends on patients. We examined the utility of a new tool, the customized online nutrition guidance system, in patients with nonalcoholic fatty liver disease (NAFLD). Seven patients plotted their body weight (BW) and marked a customized task card on completion for 90 days on a website. The instructors encouraged them by e-mail. BW, serum transaminase levels, and system usage were evaluated. The results showed that BW and serum alanine aminotransferase levels were significantly lower than at baseline. BW and task visualization as well as encouragement by e-mails were effective in ensuring continuity. Thus, this system is effective in keeping NAFLD patients motivated to continue their diet therapy. PMID:28674352

  16. Ground Simulation of an Autonomous Satellite Rendezvous and Tracking System Using Dual Robotic Systems

    Science.gov (United States)

    Trube, Matthew J.; Hyslop, Andrew M.; Carignan, Craig R.; Easley, Joseph W.

    2012-01-01

    A hardware-in-the-loop ground system was developed for simulating a robotic servicer spacecraft tracking a target satellite at short range. A relative navigation sensor package "Argon" is mounted on the end-effector of a Fanuc 430 manipulator, which functions as the base platform of the robotic spacecraft servicer. Machine vision algorithms estimate the pose of the target spacecraft, mounted on a Rotopod R-2000 platform, relay the solution to a simulation of the servicer spacecraft running in "Freespace", which performs guidance, navigation and control functions, integrates dynamics, and issues motion commands to a Fanuc platform controller so that it tracks the simulated servicer spacecraft. Results will be reviewed for several satellite motion scenarios at different ranges. Key words: robotics, satellite, servicing, guidance, navigation, tracking, control, docking.

  17. Renal access in PNL under sonographic guidance: Do we really need to insert an open end ureteral catheter in dilated renal systems? A prospective randomized study.

    Science.gov (United States)

    Eryildirim, Bilal; Tuncer, Murat; Camur, Emre; Ustun, Fatih; Tarhan, Fatih; Sarica, Kemal

    2017-10-03

    To evaluate the true necessity of open end ureteral catheter insertion in patients with moderate to severe pelvicalyceal system dilation treated with percutaneous nephrolithotomy (PNL) under sonographic guidance. 50 cases treated with PNL under sonographic guidance in prone position for solitary obstructing renal stones were evaluated. Patients were randomly divided into two groups; Group 1: Patients in whom a open end ureteral catheter was inserted prior to the procedure; Group 2: Patients receiving no catheter before PNL. In addition to the duration of the procedure as a whole and also all relevant stages as well, radiation exposure time, hospitalization period, mean nephrostomy tube duration, mean drop in Hb levels and all intra and postoperative complications have been evaluated. Mean size of the stones was 308.5 ± 133.2 mm2. Mean total duration of the PNL procedure in cases with open end ureteral catheter was significantly longer than the other cases (p < 0.001). Evaluation of the outcomes of the PNL procedures revealed no statistically significant difference between two groups regarding the stone-free rates (86% vs 84%). Additionally, there was no significant difference with respect to the duration of nephrostomy tube, hospitalization period and secondary procedures needed, complication rates as well as the post-operative Hb drop levels in both groups (p = 0.6830). Our results indicate that the placement of an open end ureteral catheter prior to a PNL procedure performed under sonographic access may not be indicated in selected cases presenting with solitary obstructing renal pelvic and/or calyceal stones.

  18. Draft Guidance for Protective Action Strategies Development

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Hyun; Jeong, Seung Young; Kim, Wanjoo [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    National nuclear emergency preparedness and response (EPR) framework has been improved since the Fukushima accident in 2011. There are still many needs to be amended and improved in regulatory requirements and technical criteria to warrant efficacy of the EPR framework. As an important part of the framework, protective actions have to be implemented with optimized and justified manner during whole emergency phases. In this study, to enhance protective action strategies in response to severe accident or general emergency, existing procedures were reviewed. And generic guidance to develop protective action recommendations (PARs) was proposed considering revised EPZ and recent technical information on protective action strategies. The generic guidance for PARs based on facility status was introduced. Revision of EPZ and some recent information on protective action strategies, such as staged evacuation, specific approach for rapidly progressing accident were considered. It would be employed as a basis to develop site-specific strategies of PARs and regulatory guidance for emergency plan by nuclear licensee. It was focused on an early phase of nuclear emergency. Further efforts to develop site specific strategies of PARs and strategies which cover full range of nuclear emergency would be followed by several stake holders.

  19. Observability-Based Guidance and Sensor Placement

    Science.gov (United States)

    Hinson, Brian T.

    Control system performance is highly dependent on the quality of sensor information available. In a growing number of applications, however, the control task must be accomplished with limited sensing capabilities. This thesis addresses these types of problems from a control-theoretic point-of-view, leveraging system nonlinearities to improve sensing performance. Using measures of observability as an information quality metric, guidance trajectories and sensor distributions are designed to improve the quality of sensor information. An observability-based sensor placement algorithm is developed to compute optimal sensor configurations for a general nonlinear system. The algorithm utilizes a simulation of the nonlinear system as the source of input data, and convex optimization provides a scalable solution method. The sensor placement algorithm is applied to a study of gyroscopic sensing in insect wings. The sensor placement algorithm reveals information-rich areas on flexible insect wings, and a comparison to biological data suggests that insect wings are capable of acting as gyroscopic sensors. An observability-based guidance framework is developed for robotic navigation with limited inertial sensing. Guidance trajectories and algorithms are developed for range-only and bearing-only navigation that improve navigation accuracy. Simulations and experiments with an underwater vehicle demonstrate that the observability measure allows tuning of the navigation uncertainty.

  20. Rendezvous technique treatment for late-onset biliary leakage after major hepatectomy of a living donor: report of a case.

    Science.gov (United States)

    Kimura, Koichi; Ikegami, Toru; Yamashita, Yo-ichi; Saeki, Hiroshi; Oki, Eiji; Yoshizumi, Tomoharu; Uchiyama, Hideaki; Kawanaka, Hirofumi; Soejima, Yuji; Morita, Masaru; Shirabe, Ken; Ikeda, Tetsuo; Maehara, Yoshihiko

    2013-09-01

    Biliary leakage is a major complication after hepatectomy. We report the case of a living-donor liver transplantation (LDLT) donor with a late-onset bile leak from the trifurcation of the hepatic duct who was successfully treated using rendezvous technique. A 52-year-old man underwent extended left hepatectomy for donation and was discharged on postoperative day (PD) 13. However, he was rehospitalized on PD 26 with severe abdominal pain. Physical examination suggested panperitonitis, and abdominocentesis showed bilious ascites. Emergent laparotomy for biliary leakage and peritonitis was performed. There was bilious ascites in the peritoneal cavity. A biliary fistula was recognized at the trifurcation of B8a, B8b, and B5. Intraoperative transhepatic biliary drainage of each bile duct was performed. Endoscopic transpapillary drainage was performed on PD 24. Finally, external drains were removed and complete internal drainage established on PD 70. The bile leak was considered to be the result of injury from electrocautery device. Appropriate making choices of the electrocautery devices enable us to avoid over thermal injury of the liver surface. Rendezvous bidirectional drainage effectively treated late-onset bile leakage from the trifurcation of a hepatic bile duct.

  1. NASA's Automated Rendezvous and Docking/Capture Sensor Development and Its Applicability to the GER

    Science.gov (United States)

    Hinkel, Heather; Cryan, Scott; DSouza, Christopher; Strube, Matthew

    2014-01-01

    This paper will address how a common Automated Rendezvous and Docking/Capture (AR&D/C) sensor suite can support Global Exploration Roadmap (GER) missions, and discuss how the model of common capability development to support multiple missions can enable system capability level partnerships and further GER objectives. NASA has initiated efforts to develop AR&D/C sensors, that are directly applicable to GER. NASA needs AR&D/C sensors for both the robotic and crewed segments of the Asteroid Redirect Mission (ARM). NASA recently conducted a commonality assessment of the concept of operations for the robotic Asteroid Redirect Vehicle (ARV) and the crewed mission segment using the Orion crew vehicle. The commonality assessment also considered several future exploration and science missions requiring an AR&D/C capability. Missions considered were asteroid sample return, satellite servicing, and planetary entry, descent, and landing. This assessment determined that a common sensor suite consisting of one or more visible wavelength cameras, a three-dimensional LIDAR along with long-wavelength infrared cameras for robustness and situational awareness could be used on each mission to eliminate the cost of multiple sensor developments and qualifications. By choosing sensor parameters at build time instead of at design time and, without having to requalify flight hardware, a specific mission can design overlapping bearing, range, relative attitude, and position measurement availability to suit their mission requirements with minimal nonrecurring engineering costs. The resulting common sensor specification provides the union of all performance requirements for each mission and represents an improvement over the current systems used for AR&D/C today. NASA's AR&D/C sensor development path could benefit the International Exploration Coordination Group (ISECG) and support the GER mission scenario by providing a common sensor suite upon which GER objectives could be achieved while

  2. British Association for the Study of Community Dentistry (BASCD) guidance on the statistical aspects of training and calibration of examiners for surveys of child dental health. A BASCD coordinated dental epidemiology programme quality standard.

    Science.gov (United States)

    Pine, C M; Pitts, N B; Nugent, Z J

    1997-03-01

    The British Association for the Study of Community Dentistry (BASCD) is responsible for the coordination of locally based surveys of child dental health which permit local and national comparisons between health authorities and regions. These surveys began in 1985/86 in England and Wales, 1987/88 in Scotland and 1993/94 in Northern Ireland. BASCD has taken an increasing lead in setting quality standards in discussion with the NHS Epidemiology Coordinators of the Dental Epidemiology Programme. This paper comprises guidance on the statistical aspects of training and calibration of examiners for these surveys.

  3. Guidance concepts for time-based flight operations

    Science.gov (United States)

    Vicroy, Dan D.

    1990-01-01

    Airport congestion and the associated delays are severe in today's airspace system and are expected to increase. NASA and the FAA is investigating various methods of alleviating this problem through new technology and operational procedures. One concept for improving airspace productivity is time-based control of aircraft. Research to date has focused primarily on the development of time-based flight management systems and Air Traffic Control operational procedures. Flight operations may, however, require special onboard guidance in order to satisfy the Air Traffic Control imposed time constraints. The results are presented of a simulation study aimed at evaluating several time-based guidance concepts in terms of tracking performance, pilot workload, and subjective preference. The guidance concepts tested varied in complexity from simple digital time-error feedback to an advanced time-referenced-energy guidance scheme.

  4. Towards a new approach to model guidance laws

    International Nuclear Information System (INIS)

    Borne, P.; Duflos, E.; Vanheeghe, P.

    1994-01-01

    Proportional navigation laws have been widely used and studied. Nevertheless very few publications explain rigorously the origin of all these laws. For researchers who are starting to work on guidance laws, a feeling of confusion can result. For others, this lack of explanation can be, for example, the source of the difficulties to make the true proportional navigation become equivalent to the pure proportional navigation. The authors propose here a way to model guidance laws in order to fill this lack of explanation. The first consequence is a better exploration of the kinematic behaviors arising during the guidance process. The second consequence is the definition of a new 3D guidance law which can be seen as a generalization of the true proportional navigation. Moreover, this generalization allow this last law to become equivalent to the pure proportional navigation in terms of initial conditions which allow the object to reach its target

  5. attitude of secondary school students towards guidance

    African Journals Online (AJOL)

    Elizabeth Egbochuku

    gender and school location significantly influenced students' attitude towards guidance ... students respond and perceive guidance and counselling services will, to ... counsellors will be appointed in post-primary institutions and tertiary levels.

  6. Accuracy Analysis of Lunar Lander Terminal Guidance Algorithm

    Directory of Open Access Journals (Sweden)

    E. K. Li

    2017-01-01

    Full Text Available This article studies a proposed analytical algorithm of the terminal guidance for the lunar lander. The analytical solution, which forms the basis of the algorithm, was obtained for a constant acceleration trajectory and thrust vector orientation programs that are essentially linear with time. The main feature of the proposed algorithm is a completely analytical solution to provide the lander terminal guidance to the desired spot in 3D space when landing on the atmosphereless body with no numerical procedures. To reach 6 terminal conditions (components of position and velocity vectors at the final time are used 6 guidance law parameters, namely time-to-go, desired value of braking deceleration, initial values of pitch and yaw angles and rates of their change. In accordance with the principle of flexible trajectories, this algorithm assumes the implementation of a regularly updated control program that ensures reaching terminal conditions from the current state that corresponds to the control program update time. The guidance law parameters, which ensure that terminal conditions are reached, are generated as a function of the current phase coordinates of a lander. The article examines an accuracy and reliability of the proposed analytical algorithm that provides the terminal guidance of the lander in 3D space through mathematical modeling of the lander guidance from the circumlunar pre-landing orbit to the desired spot near the lunar surface. A desired terminal position of the lunar lander is specified by the selenographic latitude, longitude and altitude above the lunar surface. The impact of variations in orbital parameters on the terminal guidance accuracy has been studied. By varying the five initial orbit parameters (obliquity, ascending node longitude, argument of periapsis, periapsis height, apoapsis height when the terminal spot is fixed the statistic characteristics of the terminal guidance algorithm error according to the terminal

  7. Review of soil contamination guidance

    International Nuclear Information System (INIS)

    Mueller, M.A.; Kennedy, W.E. Jr.; Soldat, J.K.

    1981-08-01

    A review of existing and proposed radioactive soil contamination standards and guidance was conducted for United Nuclear Corporation (UNC), Office of Surplus Facilities Management. Information was obtained from both government agencies and other sources during a literature survey. The more applicable standards were reviewed, evaluated, and summarized. Information pertaining to soil contamination for both facility operation and facility decommissioning was obtained from a variety of sources. These sources included: the Code of Federal Regulations, regulatory guides, the Federal Register, topical reports written by various government agencies, topical reports written by national laboratories, and publications from the American National Standards Institute (ANSI). It was difficult to directly compare the standards and guidance obtained from these sources since each was intended for a specific situation and different units or bases were used. However, most of the information reviewed was consistent with the philosophy of maintaining exposures at levels as low as reasonably achievable

  8. Guidance on future art commissioning.

    Science.gov (United States)

    2009-05-01

    Delegates at Building Better Healthcare's recent "National Patient Environment and the Arts Conference 2009" in London heard how national public arts think tank ixia has appointed Bristol-based arts and wellbeing development agency Willis Newson to write "concise and convincing guidance" on commissioning art for new healthcare facilities. A key message, during a joint presentation, was that integrating artwork into hospitals and other healthcare premises requires the earliest possible consideration to reap the maximum rewards.

  9. Current materiality guidance for auditors

    OpenAIRE

    McKee, Thomas E.; Eilifsen, Aasmund

    2000-01-01

    Auditors have to make materiality judgments on every audit. This is a difficult process, as both quantitative and qualitative factors have to be evaluated. Additionally, there is no formal guidance for how to implement the materiality concepts discussed in the auditing standards. Although they are sometimes difficult to make, good materiality judgments are crucial for the conduct of a successful audit as poor judgments can result in an audit that is ineffective and/or inefficient. This report...

  10. 2011 Army Strategic Planning Guidance

    Science.gov (United States)

    2011-03-25

    TESI ) of 22,000 Soldiers, the Army’s total force by the end of the mid-term period is programmed to be 520K (AC). We will achieve a more...dwell ratios, extending TESI authority to adequately man deploying units and sustain the All-Volunteer Force, right-sizing the generating force, and... TESI Temporary End-Strength Increase WMD Weapons of Mass Destruction 2011 ARMY STRATEGIC PLANNING GUIDANCE Page 19 2011

  11. Visual guidance of mobile platforms

    Science.gov (United States)

    Blissett, Rodney J.

    1993-12-01

    Two systems are described and results presented demonstrating aspects of real-time visual guidance of autonomous mobile platforms. The first approach incorporates prior knowledge in the form of rigid geometrical models linking visual references within the environment. The second approach is based on a continuous synthesis of information extracted from image tokens to generate a coarse-grained world model, from which potential obstacles are inferred. The use of these techniques in workplace applications is discussed.

  12. Individual plant examination: Submittal guidance

    International Nuclear Information System (INIS)

    1989-08-01

    Based on a Policy Statement on Severe Accidents Regarding Future Designs and Existing Plants, the performance of a plant examination is requested from the licensee of each nuclear power plant. The plant examination looks for vulnerabilities to severe accidents and cost-effective safety improvements that reduce or eliminate the important vulnerabilities. This document delineates guidance for reporting the results of that plant examination. 38 refs., 2 tabs

  13. Providing Career Guidance for Young Women.

    Science.gov (United States)

    Colby, Pamela G.

    This module is directed at personnel working or planning to work in the areas of guidance, counseling, placement and follow-through in junior and senior high school settings, grades 7-12. The module topic is career guidance for young women of junior and senior high school age, aand the focus will be on providing nonbiased career guidance which…

  14. Radionuclide Data Quality Evaluation Guidance

    International Nuclear Information System (INIS)

    Tucker, B.J.; Winters, M.S.; Evans, D.

    2009-01-01

    A considerable amount of radioanalytical data is generated during various phases of the characterization and remediation of radiologically-contaminated sites and properties. It is critical that data generated from the analysis of collected samples be to a level of quality usable by the project and acceptable to stakeholders. In July 2004, the final version of a multi-agency guidance manual entitled Multi-Agency Radiological Analytical Protocols Manual (MARLAP) was issued by the Environmental Protection Agency, Department of Energy, Department of Homeland Security, Nuclear Regulatory Commission, Department of Defense, National Institute of Standards and Technology, U. S. Geological Survey, Food and Drug Administration, and the States of Kentucky and California. The authors' purpose is to introduce readers to some key elements of MARLAP as it relates to radioanalytical lab quality control, and to demonstrate how these guidance elements can be effectively incorporated into mature radioanalytical lab operations and data validation regimes. Based upon the logic and statistical methodologies presented in MARLAP, the authors have revised existing project-specific Radioanalytical Data Evaluation Guidance (RadDEG) used at the FUSRAP Maywood Site in Maywood, NJ. The RadDEG allows users to qualify data in a meaningful way by tying the usability of the data to its activity and uncertainty relative to project action levels and QC results. This exercise may be useful to other projects looking to implement a MARLAP-based approach into their project/site-specific data evaluation methodologies. (authors)

  15. Using Information from Rendezvous Missions for Best-Case Appraisals of Impact Damage to Planet Earth Caused by Natural Objects

    Science.gov (United States)

    Arnold, James O.; Chodas, Paul W.; Ulamec, Stephan; Mathias, Donovan L.; Burkhard, Craig D.

    2017-01-01

    The Asteroid Threat Assessment Project (ATAP), a part of NASAs Planetary Defense Coordination Office (PDCO) has the responsibility to appraise the range of surface damage by potential asteroid impacts on land or water. If a threat is realized, the project will provide appraisals to officials empowered to make decisions about potential mitigation actions. This paper describes a scenario for assessment of surface damage when characterization of an asteroid had been accomplished by a rendezvous mission that would be conducted by the international planetary defense community. It is shown that the combination of data from ground and in-situ measurements on an asteroid provides knowledge that can be used to pin-point its impact location and predict the level of devastation it would cause. The hypothetical asteroid 2017 PDC with a size range of 160 to 290 m in diameter to be discussed at the PDC 2017 is used as an example. In order of importance for appraising potential damage, information required is: (1) where will the surface impact occur? (2) what is the mass, shape and size of the asteroid and what is its entry state (speed and entry angle) at the 100 km atmospheric pierce point? And (3) is the asteroid a monolith or a rubble pile? If it is a rubble pile, what is its structure and heterogeneity from the surface and throughout its interior? Item (1) is of first order importance to determine levels of devastation (loss of life and infrastructure damage) because it varies strongly on the impact location. Items (2) and (3) are used as inputs for ATAPs simulations to define the level of surface hazards: winds, overpressure, thermal exposure; all created by the deposition of energy during the objects atmospheric flight, andor cratering. Topics presented in this paper include: (i) the devastation predicted by 2017 PDCs impact on land based on initial observations using ATAPs risk assessment capability, (ii) how information corresponding to items (1) to (3) could be obtained

  16. Development of Safety Review Guidance for Research and Training Reactors

    International Nuclear Information System (INIS)

    Oh, Kju-Myeng; Shin, Dae-Soo; Ahn, Sang-Kyu; Lee, Hoon-Joo

    2007-01-01

    The KINS already issued the safety review guidance for pressurized LWRs. But the safety review guidance for research and training reactors were not developed. So, the technical standard including safety review guidance for domestic research and training reactors has been applied mutates mutandis to those of nuclear power plants. It is often difficult for the staff to effectively perform the safety review of applications for the permit by the licensee, based on peculiar safety review guidance. The NRC and NSC provide the safety review guidance for test and research reactors and European countries refer to IAEA safety requirements and guides. The safety review guide (SRG) of research and training reactors was developed considering descriptions of the NUREG- 1537 Part 2, previous experiences of safety review and domestic regulations for related facilities. This study provided the safety review guidance for research and training reactors and surveyed the difference of major acceptance criteria or characteristics between the SRG of pressurized light water reactor and research and training reactors

  17. Remotely supported prehospital ultrasound: A feasibility study of real-time image transmission and expert guidance to aid diagnosis in remote and rural communities.

    Science.gov (United States)

    Eadie, Leila; Mulhern, John; Regan, Luke; Mort, Alasdair; Shannon, Helen; Macaden, Ashish; Wilson, Philip

    2017-01-01

    Introduction Our aim is to expedite prehospital assessment of remote and rural patients using remotely-supported ultrasound and satellite/cellular communications. In this paradigm, paramedics are remotely-supported ultrasound operators, guided by hospital-based specialists, to record images before receiving diagnostic advice. Technology can support users in areas with little access to medical imaging and suboptimal communications coverage by connecting to multiple cellular networks and/or satellites to stream live ultrasound and audio-video. Methods An ambulance-based demonstrator system captured standard trauma and novel transcranial ultrasound scans from 10 healthy volunteers at 16 locations across the Scottish Highlands. Volunteers underwent brief scanning training before receiving expert guidance via the communications link. Ultrasound images were streamed with an audio/video feed to reviewers for interpretation. Two sessions were transmitted via satellite and 21 used cellular networks. Reviewers rated image and communication quality, and their utility for diagnosis. Transmission latency and bandwidth were recorded, and effects of scanner and reviewer experience were assessed. Results Appropriate views were provided in 94% of the simulated trauma scans. The mean upload rate was 835/150 kbps and mean latency was 114/2072 ms for cellular and satellite networks, respectively. Scanning experience had a significant impact on time to achieve a diagnostic image, and review of offline scans required significantly less time than live-streamed scans. Discussion This prehospital ultrasound system could facilitate early diagnosis and streamlining of treatment pathways for remote emergency patients, being particularly applicable in rural areas worldwide with poor communications infrastructure and extensive transport times.

  18. Cannabinoid receptor CB2 modulates axon guidance

    DEFF Research Database (Denmark)

    Duff, Gabriel; Argaw, Anteneh; Cecyre, Bruno

    2013-01-01

    on axon guidance. These effects are specific to CB2R since no changes were observed in mice where the gene coding for this receptor was altered (cnr2 (-/-)). The CB2R induced morphological changes observed at the growth cone are PKA dependent and require the presence of the netrin-1 receptor, Deleted...... CB2R's implication in retinothalamic development. Overall, this study demonstrates that the contribution of endocannabinoids to brain development is not solely mediated by CB1R, but also involves CB2R....

  19. Avoiding plagiarism: guidance for nursing students.

    Science.gov (United States)

    Price, Bob

    The pressures of study, diversity of source materials, past assumptions relating to good writing practice, ambiguous writing guidance on best practice and students' insecurity about their reasoning ability, can lead to plagiarism. With the use of source checking software, there is an increased chance that plagiarised work will be identified and investigated, and penalties given. In extreme cases, plagiarised work may be reported to the Nursing and Midwifery Council and professional as well as academic penalties may apply. This article provides information on how students can avoid plagiarism when preparing their coursework for submission.

  20. Into the Curriculum. Guidance: Sense of Self, Self-Esteem; Health: Clean Hands, Clean Books; Mathematics/Science: What's the Heaviest Thing in the Library Media Center?; Reading/Language Arts: Merry-Go-Round Mooo-ving Picture Show; Social Studies: I Came to School By !; Social Studies: Revolutionary War Facts.

    Science.gov (United States)

    School Library Media Activities Monthly, 2001

    2001-01-01

    Provides six fully developed library media activities that are designed for use with specific curriculum units in guidance, health, mathematics, science, reading, language arts, and social studies. Library media skills, curriculum objectives, grade levels, resources, instructional roles, procedures, evaluation, and follow-up are described for each…

  1. Pneumoperitoneum Caused by Air Leakage Through the Percutaneous Puncture Tract as a Complication of Rendezvous Technique: A Case Report

    Directory of Open Access Journals (Sweden)

    Chiao-Hsiung Chuang

    2008-11-01

    Full Text Available The rendezvous technique, combining percutaneous and endoscopic procedures, is a safe and effective method to achieve biliary cannulation if an endoscopic approach fails. The two procedures in this technique can be carried out simultaneously or in stages. A simultaneous approach is reported to be associated with fewer complications, and patients undergoing this approach can recover and be discharged more rapidly. Here, we report a complication of pneumoperitoneum in a patient who underwent percutaneous and endoscopic procedures simultaneously for the removal of a common bile duct stone. It was supposed that prolonged air insufflation during endoscopy forced intestinal air to track into the peritoneal cavity through the bile ducts and the puncture tract. Accordingly, a short wait before removing the percutaneous catheter to deflate the intestinal air will be helpful to avoid such a complication.

  2. Spacecraft Actuator Diagnosis with Principal Component Analysis: Application to the Rendez-Vous Phase of the Mars Sample Return Mission

    Directory of Open Access Journals (Sweden)

    Othman Nasri

    2015-01-01

    Full Text Available This paper presents a fault detection and isolation (FDI approach in order to detect and isolate actuators (thrusters and reaction wheels faults of an autonomous spacecraft involved in the rendez-vous phase of the Mars Sample Return (MSR mission. The principal component analysis (PCA has been adopted to estimate the relationships between the various variables of the process. To ensure the feasibility of the proposed FDI approach, a set of data provided by the industrial “high-fidelity” simulator of the MSR and representing the opening (resp., the rotation rates of the spacecraft thrusters (resp., reaction wheels has been considered. The test results demonstrate that the fault detection and isolation are successfully accomplished.

  3. Contextual Cueing Improves Attentional Guidance, Even When Guidance Is Supposedly Optimal

    OpenAIRE

    Harris, A. M.; Remington, R. W.

    2017-01-01

    Visual search through previously encountered contexts typically produces reduced reaction times compared with search through novel contexts. This contextual cueing benefit is well established, but there is debate regarding its underlying mechanisms. Eye-tracking studies have consistently shown reduced number of fixations with repetition, supporting improvements in attentional guidance as the source of contextual cueing. However, contextual cueing benefits have been shown in conditions in whic...

  4. 78 FR 4848 - Social Media: Consumer Compliance Risk Management Guidance

    Science.gov (United States)

    2013-01-23

    ...: Consumer Compliance Risk Management Guidance AGENCY: Federal Financial Institutions Examination Council... Media: Consumer Compliance Risk Management Guidance'' (guidance). Upon completion of the guidance, and... management practices adequately address the consumer compliance and legal risks, as well as related risks...

  5. Guidance on accidents involving radioactivity

    International Nuclear Information System (INIS)

    1989-01-01

    This annex contains advice to Health Authorities on their response to accidents involving radioactivity. The guidance is in six parts:-(1) planning the response required to nuclear accidents overseas, (2) planning the response required to UK nuclear accidents a) emergency plans for nuclear installations b) nuclear powered satellites, (3) the handling of casualties contaminated with radioactive substances, (4) background information for dealing with queries from the public in the event of an accident, (5) the national arrangements for incident involving radioactivity (NAIR), (6) administrative arrangements. (author)

  6. Advantages of computed tomographic guidance

    International Nuclear Information System (INIS)

    Casola, G.; Vansonnenberg, E.

    1987-01-01

    Both ultrasound and CT are successfully used to guide interventional procedures throughout the body. There are advantages and disadvantages to each modality and choosing one over the other will vary from case to case. Major factors influencing choice are discussed in this paper. As a general rule CT guidance is usually required for lesions in the thorax, the adrenals, the pancreas, lymph nodes, and for percutaneous abscess drainage. The authors feel that a complimentary use of ultrasound and CT is essential to optimize success and cost-effectiveness; therefore, the interventional radiologist should be familiar with both imaging modalities

  7. Agent Based Individual Traffic guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen Bundgaard

    2004-01-01

    When working with traffic planning or guidance it is common practice to view the vehicles as a combined mass. >From this models are employed to specify the vehicle supply and demand for each region. As the models are complex and the calculations are equally demanding the regions and the detail...... of the road network is aggregated. As a result the calculations reveal only what the mass of vehicles are doing and not what a single vehicle is doing. This is the crucial difference to ABIT (Agent Based Individual Trafficguidance). ABIT is based on the fact that information on the destination of each vehicle...

  8. The development of an autonomous rendezvous and docking simulation using rapid integration and prototyping technology

    Science.gov (United States)

    Shackelford, John H.; Saugen, John D.; Wurst, Michael J.; Adler, James

    1991-01-01

    A generic planar 3 degree of freedom simulation was developed that supports hardware in the loop simulations, guidance and control analysis, and can directly generate flight software. This simulation was developed in a small amount of time utilizing rapid prototyping techniques. The approach taken to develop this simulation tool, the benefits seen using this approach to development, and on-going efforts to improve and extend this capability are described. The simulation is composed of 3 major elements: (1) Docker dynamics model, (2) Dockee dynamics model, and (3) Docker Control System. The docker and dockee models are based on simple planar orbital dynamics equations using a spherical earth gravity model. The docker control system is based on a phase plane approach to error correction.

  9. Ecological Restoration: Guidance from Theory

    Directory of Open Access Journals (Sweden)

    Joy Zedler

    2005-09-01

    Full Text Available A review of the science and practice of ecosystem restoration led me to identify key ecological theories and concepts that are relevant to planning, implementing, and sustaining restoration efforts. From experience with actual restoration projects, I provide guidance for improving the restoration process. Despite an abundance of theory and guidance, restoration goals are not always achieved, and pathways toward targets are not highly predictable. This is understandable, since each restoration project has many constraints and unique challenges. To improve restoration progress, I advise that sites be designed as experiments to allow learning while doing. At least the larger projects can be restored in phases, each designed as experimental treatments to test alternative restoration approaches. Subsequent phases can then adopt one or more of the treatments that best achieved goals in earlier phases while applying new tests of other restoration measures. Both science and restoration can progress simultaneously. This phased, experimental approach (called “adaptive restoration” is an effective tool for improving restoration when monitoring, assessment, interpretation and research are integrated into the process.

  10. Laser guidance of mesoscale particles

    Science.gov (United States)

    Underdown, Frank Hartman, Jr.

    Mesoscale particles are guided and trapped in hollow optical fibers using radiation pressure forces. Laser light from a 0.4W, 780nm diode laser is guided in a low- loss fiber mode and used to generate the guidance forces. Laser scattering and absorption forces propels particles along the fiber and polarization gradient forces attract them to the fiber's axial center. Using two counter propagating laser beams, inside the fiber, particles can be trapped in three dimensions. Measuring the spring constant of the trap gives the gradient force. This dissertation describes Rayleigh and Mie scattering models for calculating guidance forces. Calculated forces as a function of particle size and composition (i.e. dielectric, semiconductor, and metals) will be presented. For example, under typical experimental conditions 100nm Au particles are guided by a 2 × 10-14 N propulsive force in a water filled fiber. In comparison, the measured force, obtained from the particle's velocity and Stokes' law, is 7.98 × 10-14 N.

  11. The axonal guidance receptor neogenin promotes acute inflammation.

    Directory of Open Access Journals (Sweden)

    Klemens König

    Full Text Available Neuronal guidance proteins (NGP were originally described in the context of axonal growth and migration. Yet recent work has demonstrated that NGPs also serve as guidance cues for immune competent cells. A crucial target receptor for NGPs during embryonic development is the neogenin receptor, however its role during acute inflammation is unknown. We report here that neogenin is abundantly expressed outside the nervous system and that animals with endogenous repression of neogenin (Neo1(-/- demonstrate attenuated changes of acute inflammation. Studies using functional inhibition of neogenin resulted in a significant attenuation of inflammatory peritonitis. In studies employing bone marrow chimeric animals we found the hematopoietic presence of Neo1(-/- to be responsible for the attenuated inflammatory response. Taken together our studies suggest that the guidance receptor neogenin holds crucial importance for the propagation of an acute inflammatory response and further define mechanisms shared between the nervous and the immune system.

  12. Guidance documents relating to landfills and contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Schomaker, N.B.; Zunt, D.A.

    1990-01-01

    The Environmental Protection Agency is developing and updating a series of Technical Guidance Documents to provide best engineering control technology to meet the needs of the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), respectively. These documents are the compilation of the research efforts to date relating to containment of pollutants from waste disposal to the land as relates to residuals management. The specific areas of research being conducted under the RCRA land disposal program relates to laboratory, pilot and field validation studies in cover systems, waste leaching and solidification, liner systems and disposal facility evaluation. The specific areas of research being conducted under the CERCLA uncontrolled waste sites (Superfund) program relate to in situ treatment, solidification/stabilization for treating hazardous waste, combustion technologies, best demonstrated available technology (BDAT), on-site treatment technologies, emerging biosystems, expert systems, personnel health protection equipment, and site and situation assessment. The Guidance Documents are intended to assist both the regulated community and the permitting authorities, as well as the Program Offices, and Regions, as well as the states and other interested parties, with the latest information relevant to waste management.

  13. Health Service use of ionising radiations: Guidance

    International Nuclear Information System (INIS)

    1995-01-01

    This booklet gives outline guidance on the use of ionising radiations in the Health Service in the United Kingdom. Extensive reference is made to documents where more detailed information may be found. The guidance covers general advice on the medical use of ionising radiations, statutory requirements, and guidance on selected Health Service issues such as patient identification procedures, information management systems, deviations from prescribed radiation dose, imaging and radiotherapy. (57 references) (U.K.)

  14. Hybrid Guidance Control for a Hypervelocity Small Size Asteroid Interceptor Vehicle

    Science.gov (United States)

    Zebenay, Melak M.; Lyzhoft, Joshua R.; Barbee, Brent W.

    2017-01-01

    Near-Earth Objects (NEOs) are comets and/or asteroids that have orbits in proximity with Earth's own orbit. NEOs have collided with the Earth in the past, which can be seen at such places as Chicxulub crater, Barringer crater, and Manson crater, and will continue in the future with potentially significant and devastating results. Fortunately such NEO collisions with Earth are infrequent, but can happen at any time. Therefore it is necessary to develop and validate techniques as well as technologies necessary to prevent them. One approach to mitigate future NEO impacts is the concept of high-speed interceptor. This concept is to alter the NEO's trajectory via momentum exchange by using kinetic impactors as well as nuclear penetration devices. The interceptor has to hit a target NEO at relative velocity which imparts a sufficient change in NEO velocity. NASA's Deep Impact mission has demonstrated this scenario by intercepting Comet Temple 1, 5 km in diameter, with an impact relative speed of approximately 10 km/s. This paper focuses on the development of hybrid guidance navigation and control (GNC) algorithms for precision hypervelocity intercept of small sized NEOs. The spacecraft's hypervelocity and the NEO's small size are critical challenges for a successful mission as the NEO will not fill the field of view until a few seconds before intercept. The investigation needs to consider the error sources modeled in the navigation simulation such as spacecraft initial state uncertainties in position and velocity. Furthermore, the paper presents three selected spacecraft guidance algorithms for asteroid intercept and rendezvous missions. The selected algorithms are classical Proportional Navigation (PN) based guidance that use a first order difference to compute the derivatives, Three Plane Proportional Navigation (TPPN), and the Kinematic Impulse (KI). A manipulated Bennu orbit that has been changed to impact Earth will be used as a demonstrative example to compare the

  15. Seamless Guidance System Combining GPS, BLE Beacon, and NFC Technologies

    Directory of Open Access Journals (Sweden)

    Rung-Shiang Cheng

    2016-01-01

    Full Text Available Users rely increasingly on Location-Based Services (LBS and automated navigation/guidance systems nowadays. However, while such services are easily implemented in outdoor environments using Global Positioning System (GPS technology, a requirement still exists for accurate localization and guidance schemes in indoor settings. Accordingly, the present study proposes a system based on GPS, Bluetooth Low Energy (BLE beacons, and Near Field Communication (NFC technology. Through establishing graphic information and the design of algorithm, this study develops a guidance system for indoors and outdoors on smart phones, wishing to give user perfect smart life through this system. The proposed system is implemented on a smart phone and evaluated on a student campus environment. The experimental results confirm the ability of the proposed app to switch automatically from an outdoor mode to an indoor mode and to guide the user to requested target destination via the shortest possible route.

  16. ICRP guidance on radioactive waste disposal

    International Nuclear Information System (INIS)

    Cooper, J.R.

    2002-01-01

    The International Commission on Radiological Protection (ICRP) issued recommendations for a system of radiological protection in 1991 as the 1990 Recommendations. Guidance on the application of these recommendations in the general area of waste disposal was issued in 1997 as Publication 77 and guidance specific to disposal of solid long-lived radioactive waste was issued as Publication 81. This paper summarises ICRP guidance in radiological protection requirements for waste disposal concentrating on the ones of relevance to the geological disposal of solid radioactive waste. Suggestions are made for areas where further work is required to apply the ICRP guidance. (author)

  17. Group guidance services to improved creativity for teachers

    Directory of Open Access Journals (Sweden)

    Solihatun Solihatun

    2017-11-01

    Full Text Available Creativity in the learning process by teachers is very important in order to support the task at school. Teacher creativity allows teachers to apply various learning methods that encourage students' interest to learn from the classroom. Besides, creativity for teachers is needed to support student development. This study aims to determine the level of creativity of teachers through group guidance services. Subjects in this study involved 10 teachers at Gemma Insani Indonesia Depok. Data analysis used a quantitative approach with pre-test and post-test control group of one design. The results show effective group guidance to improve teacher creativity at Gemma Insani Indonesia Depok.

  18. Widening opportunities for career guidance

    DEFF Research Database (Denmark)

    Poulsen, Bo Klindt; Skovhus, Randi Boelskifte; Thomsen, Rie

    2017-01-01

    This chapter discusses research circles as a way of organising collaboration between career guidance researchers and practitioners. Such collaboration, it is argued, helps resist neoliberal governance mechanisms and supports social justice perspectives among teachers involved in the provision...... of career education in Danish schools. Based on a research and development project on career education, case analysis is used to explore research circles as a means for collaboration between researchers and practitioners. This analysis shows that research circles provide teachers with a space to reflect...... both in and on action. Career education is the key focus of the case presented in this chapter and it is argued that, in order to increase social mobility through education, there is a need to widen opportunities through experience-based activities among pupils in Danish schools. The chapter contends...

  19. Widening opportunities for career guidance

    DEFF Research Database (Denmark)

    Poulsen, Bo Klindt; Skovhus, Randi Boelskifte; Thomsen, Rie

    2018-01-01

    This chapter discusses research circles as a way of organising collaboration between career guidance researchers and practitioners. Such collaboration, it is argued, helps resist neoliberal governance mechanisms and supports social justice perspectives among teachers involved in the provision...... of career education in Danish schools. Based on a research and development project on career education, case analysis is used to explore research circles as a means for collaboration between researchers and practitioners. This analysis shows that research circles provide teachers with a space to reflect...... both in and on action. Career education is the key focus of the case presented in this chapter and it is argued that, in order to increase social mobility through education, there is a need to widen opportunities through experience-based activities among pupils in Danish schools. The chapter contends...

  20. Highly effective photonic cue for repulsive axonal guidance.

    Directory of Open Access Journals (Sweden)

    Bryan J Black

    Full Text Available In vivo nerve repair requires not only the ability to regenerate damaged axons, but most importantly, the ability to guide developing or regenerating axons along paths that will result in functional connections. Furthermore, basic studies in neuroscience and neuro-electronic interface design require the ability to construct in vitro neural circuitry. Both these applications require the development of a noninvasive, highly effective tool for axonal growth-cone guidance. To date, a myriad of technologies have been introduced based on chemical, electrical, mechanical, and hybrid approaches (such as electro-chemical, optofluidic flow and photo-chemical methods. These methods are either lacking in desired spatial and temporal selectivity or require the introduction of invasive external factors. Within the last fifteen years however, several attractive guidance cues have been developed using purely light based cues to achieve axonal guidance. Here, we report a novel, purely optical repulsive guidance technique that uses low power, near infrared light, and demonstrates the guidance of primary goldfish retinal ganglion cell axons through turns of up to 120 degrees and over distances of ∼90 µm.

  1. The impact of trauma on the psyche of the individual using the film Belleville Rendez-vous as an illustrative vehicle.

    Science.gov (United States)

    Waldron, Sharn

    2008-09-01

    Using the film Belleville Rendez-vous as a vehicle for discussion, this paper argues that whilst a traumatic complex may bring about dissociation of the psyche, this is not the only possibility, nor is dissociation necessarily to be seen solely as a difficulty to be overcome. If trauma is experienced within the context of support and validation, the experience of trauma may generate integration not only of the trauma but also of the growth potential that the trauma has previously inhibited.

  2. Korean Graduate Students' Perceptions of Guidance and Professional Development

    Science.gov (United States)

    Lee, Kent; Lee, Hikyoung

    2017-01-01

    Past studies have indicated shortcomings in the training of graduate students in the US, especially for practical career skills, teaching skills, and non-academic careers. Students thus find professional development and guidance lacking for the demands of the modern marketplace. This study extends this research to the unique situation of current…

  3. Influence of parental guidance on teenage pregnancy among ...

    African Journals Online (AJOL)

    The study examined the influence of parental guidance on teenage pregnancy among secondary school female adolescent students in Abeokuta South Local Government Area. The instrument for data collection used for this research was questionnaire and the sampling techniques used for this study was descriptive survey ...

  4. Academic guidance for undergraduate students in a South African ...

    African Journals Online (AJOL)

    Higher education institutions, including medical schools, still grapple with the challenge of poor academic performance of students. Some studies report the positive results of providing academic guidance for common challenges such as poor and/or ineffective time management, study methods, test- and exam-taking ...

  5. Gender Differences in Students' Perceptions of School Guidance ...

    African Journals Online (AJOL)

    The purpose of this study was to examine gender differences in relation to students' perceptions of school guidance and counselling (G&C) services in Mberengwa district, Zimbabwe. The convergent parallel design was used in the study. A total of 114 students (68 males and 76 females) randomly selected students ...

  6. Attitude of secondary school students towards guidance and ...

    African Journals Online (AJOL)

    The Study investigated the attitude of secondary students towards guidance and counselling services. Descriptive research design of the survey type was used. Three hypotheses were formulated to guide the study. A total of 400 secondary school students were selected from ten (10) schools through stratified random ...

  7. Guidance for evidence-informed policies about health systems: rationale for and challenges of guidance development.

    Directory of Open Access Journals (Sweden)

    Xavier Bosch-Capblanch

    Full Text Available In the first paper in a three-part series on health systems guidance, Xavier Bosch-Capblanch and colleagues examine how guidance is currently formulated in low- and middle-income countries, and the challenges to developing such guidance.

  8. 78 FR 48175 - Retrospective Review of Draft Guidance Documents Issued Before 2010; Withdrawal of Guidances

    Science.gov (United States)

    2013-08-07

    ... guidances (number 19 through 22), contact the Office of Pharmaceutical Science in CDER. 23. ``Qualifying for... to the pharmaceutical industry. In most cases, FDA has developed other guidances and resources to... guidances: 1. ``Manufacturing, Processing, or Holding Active Pharmaceutical Ingredients''--issued April 1998...

  9. 78 FR 66743 - Draft Guidance for Industry on Bioequivalence Recommendations for Iron Sucrose; Availability

    Science.gov (United States)

    2013-11-06

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2007-D-0369] Draft Guidance for Industry on Bioequivalence Recommendations for Iron Sucrose; Availability AGENCY... guidance, FDA recommended an in vivo fasting BE study with pharmacokinetic endpoints and in vitro studies...

  10. The Consideration of a Constructivist Evaluation Framework in Adult Guidance Practice

    Science.gov (United States)

    Hearne, Lucy

    2011-01-01

    This article explores the findings of a doctoral study that examined the measurement of individual progression in the Irish Adult Education Guidance Initiative. The critical constructivist stance of the study challenges the prevalence of the positivist paradigm to evaluate long-term outcomes in adult guidance. The research highlights the…

  11. Analysis of Guidance and Counseling Program at Thika High School for the Blind, Kenya

    Science.gov (United States)

    Irungu, Mary Wangari; Wamocho, Franciscah Irangi

    2010-01-01

    The purpose of this study was to analyze the guidance and counseling program at Thika High School for the Blind, the only residential secondary school for students with visual impairments in Kenya. The study examined the content of the existing guidance and counseling program and whether the teacher counselors were adequately trained to handle the…

  12. The Consequences of Fading Instructional Guidance on Delayed Performance: The Case of Financial Services Training

    Science.gov (United States)

    Kissane, Mark; Kalyuga, Slava; Chandler, Paul; Sweller, John

    2008-01-01

    Empirical studies within a cognitive load framework have determined that for novice learners, worked examples provide appropriate levels of instructional guidance. As learners advance in specific subject domains, worked examples should be gradually replaced by practice problems with limited guidance. This study compared performance, both…

  13. Consideration of health inequalities in systematic reviews: a mapping review of guidance.

    Science.gov (United States)

    Maden, Michelle

    2016-11-28

    Given that we know that interventions shown to be effective in improving the health of a population may actually widen the health inequalities gap while others reduce it, it is imperative that all systematic reviewers consider how the findings of their reviews may impact (reduce or increase) on the health inequality gap. This study reviewed existing guidance on incorporating considerations of health inequalities in systematic reviews in order to examine the extent to which they can help reviewers to incorporate such issues. A mapping review was undertaken to identify guidance documents that purported to inform reviewers on whether and how to incorporate considerations of health inequalities. Searches were undertaken in Medline, CINAHL and The Cochrane Library Methodology Register. Review guidance manuals prepared by international organisations engaged in undertaking systematic reviews, and their associated websites were scanned. Studies were included if they provided an overview or discussed the development and testing of guidance for dealing with the incorporation of considerations of health inequalities in evidence synthesis. Results are summarised in narrative and tabular forms. Twenty guidance documents published between 2009 and 2016 were included. Guidance has been produced to inform considerations of health inequalities at different stages of the systematic review process. The Campbell and Cochrane Equity Group have been instrumental in developing and promoting such guidance. Definitions of health inequalities and guidance differed across the included studies. All but one guidance document were transparent in their method of production. Formal methods of evaluation were reported for six guidance documents. Most of the guidance was operationalised in the form of examples taken from published systematic reviews. The number of guidance items to operationalise ranges from 3 up to 26 with a considerable overlap noted. Adhering to the guidance will require more

  14. 48 CFR 427.104 - General guidance.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false General guidance. 427.104... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS General 427.104 General guidance. As used in FAR part 27, the agency head or agency head designee is the Senior Procurement Executive, except under FAR 27.306(a) and (b...

  15. Driving change : sustainable development action plans Guidance

    OpenAIRE

    Sustainable Development Commission

    2008-01-01

    This guidance builds upon the Sustainable Development Commission’s previous guidance, Getting Started (August 2005), which set out the basic elements that the Sustainable Development Commission would expect to see in a good Sustainable Development Action Plan. Publisher PDF Original published August 2005.

  16. Guidance for performing preliminary assessments under CERCLA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-09-01

    EPA headquarters and a national site assessment workgroup produced this guidance for Regional, State, and contractor staff who manage or perform preliminary assessments (PAs). EPA has focused this guidance on the types of sites and site conditions most commonly encountered. The PA approach described in this guidance is generally applicable to a wide variety of sites. However, because of the variability among sites, the amount of information available, and the level of investigative effort required, it is not possible to provide guidance that is equally applicable to all sites. PA investigators should recognize this and be aware that variation from this guidance may be necessary for some sites, particularly for PAs performed at Federal facilities, PAs conducted under EPA`s Environmental Priorities Initiative (EPI), and PAs at sites that have previously been extensively investigated by EPA or others. The purpose of this guidance is to provide instructions for conducting a PA and reporting results. This guidance discusses the information required to evaluate a site and how to obtain it, how to score a site, and reporting requirements. This document also provides guidelines and instruction on PA evaluation, scoring, and the use of standard PA scoresheets. The overall goal of this guidance is to assist PA investigators in conducting high-quality assessments that result in correct site screening or further action recommendations on a nationally consistent basis.

  17. Career Guidance and Public Mental Health

    Science.gov (United States)

    Robertson, Peter J.

    2013-01-01

    Career guidance may have the potential to promote public health by contributing positively to both the prevention of mental health conditions and to population level well-being. The policy implications of this possibility have received little attention. Career guidance agencies are well placed to reach key target groups. Producing persuasive…

  18. Standards for School Guidance Programs in Maryland.

    Science.gov (United States)

    Maryland State Dept. of Education, Baltimore. Div. of Compensatory, Urban, and Supplementary Programs.

    This brochure is a checklist to rate school compliance with the standards for school guidance programs in Maryland, which were developed by the Maryland State Department of Education. The first set of standards addresses the philosophy and goals of school guidance programs in Maryland and the extent to which program goals and objectives are…

  19. HANDBOOK: HAZARDOUS WASTE INCINERATION MEASUREMENT GUIDANCE

    Science.gov (United States)

    This publication, Volume III of the Hazardous Waste Incineration Guidance Series, contains general guidance to permit writers in reviewing hazardous waste incineration permit applications and trial burn plans. he handbook is a how-to document dealing with how incineration measure...

  20. 33 CFR 385.5 - Guidance memoranda.

    Science.gov (United States)

    2010-07-01

    ... ability of the Corps of Engineers, the South Florida Water Management District, and other non-Federal... § 385.5 Guidance memoranda. (a) General. (1) Technical guidance for internal management of Corps of...) General format and content of Project Implementation Reports (§ 385.26(a)); (ii) Instructions for...

  1. Why Guidance Works Better than Punishment.

    Science.gov (United States)

    Gartrell, Dan

    1995-01-01

    Examines how guidance techniques address the full spectrum of intervention methods, from prevention to conflict resolution to long-term management strategies. Discusses how punishment affects both children and teachers. Suggests that to put guidance into practice teachers should: be realistic, tailor activities to each child, practice positive…

  2. Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures

    Directory of Open Access Journals (Sweden)

    Katharine E. Alter

    2017-12-01

    Full Text Available Injections of botulinum neurotoxins (BoNTs are prescribed by clinicians for a variety of disorders that cause over-activity of muscles; glands; pain and other structures. Accurately targeting the structure for injection is one of the principle goals when performing BoNTs procedures. Traditionally; injections have been guided by anatomic landmarks; palpation; range of motion; electromyography or electrical stimulation. Ultrasound (US based imaging based guidance overcomes some of the limitations of traditional techniques. US and/or US combined with traditional guidance techniques is utilized and or recommended by many expert clinicians; authors and in practice guidelines by professional academies. This article reviews the advantages and disadvantages of available guidance techniques including US as well as technical aspects of US guidance and a focused literature review related to US guidance for chemodenervation procedures including BoNTs injection.

  3. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers-Part II. general guidance and tips

    International Nuclear Information System (INIS)

    Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho; Lee, June Young

    2015-01-01

    Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies

  4. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers-Part I. general guidance and tips

    International Nuclear Information System (INIS)

    Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho; Lee, June Young

    2015-01-01

    In the field of diagnostic test accuracy (DTA), the use of systematic review and meta-analyses is steadily increasing. By means of objective evaluation of all available primary studies, these two processes generate an evidence-based systematic summary regarding a specific research topic. The methodology for systematic review and meta-analysis in DTA studies differs from that in therapeutic/interventional studies, and its content is still evolving. Here we review the overall process from a practical standpoint, which may serve as a reference for those who implement these methods

  5. Guidance of Spatial Attention by Incidental Learning and Endogenous Cuing

    Science.gov (United States)

    Jiang, Yuhong V.; Swallow, Khena M.; Rosenbaum, Gail M.

    2013-01-01

    Our visual system is highly sensitive to regularities in the environment. Locations that were important in one's previous experience are often prioritized during search, even though observers may not be aware of the learning. In this study we characterized the guidance of spatial attention by incidental learning of a target's spatial probability,…

  6. The Vocational Guidance Research Database: A Scientometric Approach

    Science.gov (United States)

    Flores-Buils, Raquel; Gil-Beltran, Jose Manuel; Caballer-Miedes, Antonio; Martinez-Martinez, Miguel Angel

    2012-01-01

    The scientometric study of scientific output through publications in specialized journals cannot be undertaken exclusively with the databases available today. For this reason, the objective of this article is to introduce the "Base de Datos de Investigacion en Orientacion Vocacional" [Vocational Guidance Research Database], based on the…

  7. A Framework For Agent-Based Educational Guidance And ...

    African Journals Online (AJOL)

    This work applies principles of artificial intelligence and agent development of educational guidance and counselling. An agent – based expert system is developed. The system supports the storage and intelligent interactive processing of the knowledge acquired by study and experience of the human expert in the domain ...

  8. Determinants of nutrition guidance practices of primary-care physicians

    NARCIS (Netherlands)

    Hiddink, G.J.

    1996-01-01


    The aim of the studies described in this thesis was to analyze nutrition guidance practices of primary-care physicians (PCPs), their nutritional attitudes and knowledge and their interest in the role of nutrition in health and disease. A second objective was to identify the determinants

  9. Automated Guidance for Thermodynamics Essays: Critiquing versus Revisiting

    Science.gov (United States)

    Donnelly, Dermot F.; Vitale, Jonathan M.; Linn, Marcia C.

    2015-01-01

    Middle school students struggle to explain thermodynamics concepts. In this study, to help students succeed, we use a natural language processing program to analyze their essays explaining the aspects of thermodynamics and provide guidance based on the automated score. The 346 sixth-grade students were assigned to either the critique condition…

  10. Optofluidic control of axonal guidance

    Science.gov (United States)

    Gu, Ling; Ordonez, Simon; Black, Bryan; Mohanty, Samarendra K.

    2013-03-01

    Significant efforts are being made for control on axonal guidance due to its importance in nerve regeneration and in the formation of functional neuronal circuitry in-vitro. These include several physical (topographic modification, optical force, and electric field), chemical (surface functionalization cues) and hybrid (electro-chemical, photochemical etc) methods. Here, we report comparison of the effect of linear flow versus microfluidic flow produced by an opticallydriven micromotor in guiding retinal ganglion axons. A circularly polarized laser tweezers was used to hold, position and spin birefringent calcite particle near growth cone, which in turn resulted in microfluidic flow. The flow rate and resulting shear-force on axons could be controlled by a varying the power of the laser tweezers beam. The calcite particles were placed separately in one chamber and single particle was transported through microfluidic channel to another chamber containing the retina explant. In presence of flow, the turning of axons was found to strongly correlate with the direction of flow. Turning angle as high as 90° was achieved. Optofluidic-manipulation can be applied to other types of mammalian neurons and also can be extended to stimulate mechano-sensing neurons.

  11. Relationship between automation trust and operator performance for the novice and expert in spacecraft rendezvous and docking (RVD).

    Science.gov (United States)

    Niu, Jianwei; Geng, He; Zhang, Yijing; Du, Xiaoping

    2018-09-01

    Operator trust in automation is a crucial factor influencing its use and operational performance. However, the relationship between automation trust and performance remains poorly understood and requires further investigation. The objective of this paper is to explore the difference in trust and performance on automation-aided spacecraft rendezvous and docking (RVD) between the novice and the expert and to investigate the relationship between automation trust and performance as well. We employed a two-factor mixed design, with training skill (novice and expert) and automation mode (manual RVD and automation aided RVD) serving as the two factors. Twenty participants, 10 novices and 10 experts, were recruited to conduct six RVD tasks for two automation levels. After the tasks, operator performance was recorded by the desktop hand-held docking training equipment. Operator trust was also measured by a 12-items questionnaire at the beginning and end of each trial. As a result, automation narrowed the performance gap significantly between the novice and the expert, and the automation trust showed a marginally significant difference between the novice and the expert. Furthermore, the result demonstrated that the attitude angle control error of the expert was related to the total trust score, whereas other automation performance indicators were not related to the total score of trust. However, automation performance was related to the dimensions of trust, such as entrust, harmful, and dependable. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. The Space Operations Simulation Center (SOSC) and Closed-Loop Hardware Testing for Orion Rendezvous System Design

    Science.gov (United States)

    Milenkovic, Zoran; DSouza, Christopher; Huish, David; Bendle, John; Kibler, Angela

    2012-01-01

    The exploration goals of Orion / MPCV Project will require a mature Rendezvous, Proximity Operations and Docking (RPOD) capability. Ground testing autonomous docking with a next-generation sensor such as the Vision Navigation Sensor (VNS) is a critical step along the path of ensuring successful execution of autonomous RPOD for Orion. This paper will discuss the testing rationale, the test configuration, the test limitations and the results obtained from tests that have been performed at the Lockheed Martin Space Operations Simulation Center (SOSC) to evaluate and mature the Orion RPOD system. We will show that these tests have greatly increased the confidence in the maturity of the Orion RPOD design, reduced some of the latent risks and in doing so validated the design philosophy of the Orion RPOD system. This paper is organized as follows: first, the objectives of the test are given. Descriptions of the SOSC facility, and the Orion RPOD system and associated components follow. The details of the test configuration of the components in question are presented prior to discussing preliminary results of the tests. The paper concludes with closing comments.

  13. Omnidirectional angle constraint based dynamic six-degree-of-freedom measurement for spacecraft rendezvous and docking simulation

    Science.gov (United States)

    Shi, Shendong; Yang, Linghui; Lin, Jiarui; Ren, Yongjie; Guo, Siyang; Zhu, Jigui

    2018-04-01

    In this paper we present a novel omnidirectional angle constraint based method for dynamic 6-DOF (six-degree-of-freedom) measurement. A photoelectric scanning measurement network is employed whose photoelectric receivers are fixed on the measured target. They are in a loop distribution and receive signals from rotating transmitters. Each receiver indicates an angle constraint direction. Therefore, omnidirectional angle constraints can be constructed in each rotation cycle. By solving the constrained optimization problem, 6-DOF information can be obtained, which is independent of traditional rigid coordinate system transformation. For the dynamic error caused by the measurement principle, we present an interpolation method for error reduction. Accuracy testing is performed in an 8  ×  8 m measurement area with four transmitters. The experimental results show that the dynamic orientation RMSEs (root-mean-square errors) are reduced from 0.077° to 0.044°, 0.040° to 0.030° and 0.032° to 0.015° in the X, Y, and Z axes, respectively. The dynamic position RMSE is reduced from 0.65 mm to 0.24 mm. This method is applied during the final approach phase in the rendezvous and docking simulation. Experiments under different conditions are performed in a 40  ×  30 m area, and the method is verified to be effective.

  14. Studying wind energy/bird interactions: a guidance document. Metrics and methods for determining or monitoring potential impacts on birds at existing and proposed wind energy sites

    Science.gov (United States)

    Anderson, R.; Morrison, M.; Sinclair, K.; Strickland, D.; Davis, H.; Kendall, W.

    1999-01-01

    In the 1980s little was known about the potential environmental effects associated with large scale wind energy development. Although wind turbines have been used in farming and remote location applications throughout this country for centuries, impacts on birds resulting from these dispersed turbines had not been reported. Thus early wind energy developments were planned, permitted, constructed, and operated with little consideration for the potential effects on birds. In the ensuing years wind plant impacts on birds became a source of concern among a number of stakeholder groups. Based on the studies that have been done to date, significant levels of bird fatalities have been identified at only one major commercial wind energy development in the United States. Research on wind energy/bird interactions has spanned such a wide variety of protocols and vastly different levels of study effort that it is difficult to make comparisons among study findings. As a result there continues to be interest, confusion, and concern over wind energy development's potential impacts on birds. Some hypothesize that technology changes, such as less dense wind farms with larger, slower-moving turbines, will decrease the number of bird fatalities from wind turbines. Others hypothesize that, because the tip speed may be the same or faster, new turbines will not result in decreased bird fatalities but may actually increase bird impacts. Statistically significant data sets from scientifically rigorous studies will be required before either hypothesis can be tested.

  15. Contribution Locus of Control and Self Esteem to Student Academic Procrastination (Study at Department of Islamic Guidance And Counseling, IAIN IB Padang

    Directory of Open Access Journals (Sweden)

    Juliana Batubara

    2017-08-01

    Full Text Available This study aims to: (1 describe the locus of control, self-esteem and student academic procrastination (2 express the contribution of locus of control and self-esteem to student academic procrastination. This research is conducted by the expost-facto method with questionnaire instrument which has been measured its validity and reliability. The population in this study were BKI FTK IAIN IB Padang students entering 2014, 2013 and 2012 totaling 355 people, the samples used were Stratified Proportional Random Sampling technique so that the sample of 107 students was obtained. Sample amounted to 107 students. The result of the research shows that (1 locus of control is classified moderately, student self-esteem is on average high and student academic procrastination rate is high. (2 there is a significant contribution between locus of control and self-esteem on student academic procrastination jointly equal to 18.8%.

  16. 75 FR 33311 - Guidance for Industry on Bioequivalence Recommendations for Specific Products; Availability

    Science.gov (United States)

    2010-06-11

    ... available recommendations on how to design product-specific BE studies to support ANDAs. Under this process... thinking on a new process for making available to sponsors FDA guidance on how to design product-specific... ``Bioequivalence Recommendations for Specific Products.'' This guidance describes a new process for making...

  17. 76 FR 60503 - Guidance for Industry on Target Animal Safety and Effectiveness Protocol Development and...

    Science.gov (United States)

    2011-09-29

    ... Safety and Effectiveness Protocol Development and Submission.'' The purpose of this document is to provide sponsors guidance in preparation of study protocols for review by the Center for Veterinary Medicine, Office of New Animal Drug Evaluation. The recommendations included in this guidance are intended...

  18. 76 FR 1173 - Draft Guidance for Industry on Electronic Source Documentation in Clinical Investigations...

    Science.gov (United States)

    2011-01-07

    ... Web page at http://www.fda.gov/RegulatoryInformation/Guidances/default.htm . FDA guidances are issued and updated regularly. We recommend you check the Web site to ensure that you have the most up-to-date... electronic diaries provided by study subjects. When paper source documents are available for review, tracing...

  19. Optimal guidance law in quantum mechanics

    International Nuclear Information System (INIS)

    Yang, Ciann-Dong; Cheng, Lieh-Lieh

    2013-01-01

    Following de Broglie’s idea of a pilot wave, this paper treats quantum mechanics as a problem of stochastic optimal guidance law design. The guidance scenario considered in the quantum world is that an electron is the flight vehicle to be guided and its accompanying pilot wave is the guidance law to be designed so as to guide the electron to a random target driven by the Wiener process, while minimizing a cost-to-go function. After solving the stochastic optimal guidance problem by differential dynamic programming, we point out that the optimal pilot wave guiding the particle’s motion is just the wavefunction Ψ(t,x), a solution to the Schrödinger equation; meanwhile, the closed-loop guidance system forms a complex state–space dynamics for Ψ(t,x), from which quantum operators emerge naturally. Quantum trajectories under the action of the optimal guidance law are solved and their statistical distribution is shown to coincide with the prediction of the probability density function Ψ ∗ Ψ. -- Highlights: •Treating quantum mechanics as a pursuit-evasion game. •Reveal an interesting analogy between guided flight motion and guided quantum motion. •Solve optimal quantum guidance problem by dynamic programming. •Gives a formal proof of de Broglie–Bohm’s idea of a pilot wave. •The optimal pilot wave is shown to be a wavefunction solved from Schrödinger equation

  20. Optimal guidance law in quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ciann-Dong, E-mail: cdyang@mail.ncku.edu.tw; Cheng, Lieh-Lieh, E-mail: leo8101@hotmail.com

    2013-11-15

    Following de Broglie’s idea of a pilot wave, this paper treats quantum mechanics as a problem of stochastic optimal guidance law design. The guidance scenario considered in the quantum world is that an electron is the flight vehicle to be guided and its accompanying pilot wave is the guidance law to be designed so as to guide the electron to a random target driven by the Wiener process, while minimizing a cost-to-go function. After solving the stochastic optimal guidance problem by differential dynamic programming, we point out that the optimal pilot wave guiding the particle’s motion is just the wavefunction Ψ(t,x), a solution to the Schrödinger equation; meanwhile, the closed-loop guidance system forms a complex state–space dynamics for Ψ(t,x), from which quantum operators emerge naturally. Quantum trajectories under the action of the optimal guidance law are solved and their statistical distribution is shown to coincide with the prediction of the probability density function Ψ{sup ∗}Ψ. -- Highlights: •Treating quantum mechanics as a pursuit-evasion game. •Reveal an interesting analogy between guided flight motion and guided quantum motion. •Solve optimal quantum guidance problem by dynamic programming. •Gives a formal proof of de Broglie–Bohm’s idea of a pilot wave. •The optimal pilot wave is shown to be a wavefunction solved from Schrödinger equation.