WorldWideScience

Sample records for facilitated antegrade steering

  1. Understanding Antegrade Colonic Enema (ACE) Surgery

    Science.gov (United States)

    ... Colonic Enema (ACE) Surgery Antegrade Colonic Enema (ACE) Surgery Antegrade colonic enema surgery (ACE) is a procedure ... Risks / Benefits What is antegrade colonic enema (ACE) surgery? Antegrade colonic enema surgery (ACE) or Malone antegrade ...

  2. Use of the profunda femoris to facilitate closure of an antegrade puncture with the StarClose device after proximal SFA angioplasty.

    Science.gov (United States)

    Yeung-Ngok-Kao, Susan; Fisher, Robert Kendall; Williams, Robin Edward Thomas; Jackson, Ralph; Rose, John; Macdonald, Sumaira

    2006-08-01

    To report a novel technique for safely closing antegrade common femoral artery (CFA) punctures using the StarClose device after proximal superficial femoral artery (SFA) angioplasty. The vessel locator of the StarClose device should not be deployed within a recently dilated vessel, so after proximal SFA angioplasty, the sheath is withdrawn into the CFA. A second guidewire is inserted into the profunda femoris artery followed by insertion of the StarClose sheath. The vessel locator is deployed in the profunda main stem and withdrawn into the CFA until resistance is felt, indicating apposition to the luminal aspect of the vessel wall. The device is subsequently deployed according to the manufacturer's instructions. Use of profunda femoris artery allows safe closure of the CFA using the StarClose device following antegrade puncture for proximal SFA angioplasty.

  3. Steering handbook

    CERN Document Server

    Pfeffer, Peter

    2017-01-01

    This edited volume presents basic principles as well as advanced concepts of the computational modeling of steering systems. Moreover, the book includes the components and functionalities of modern steering system, which are presented comprehensively and in a practical way. The book is written by more than 15 leading experts from the automotive industry and its components suppliers. The target audience primarily comprises practicing engineers, developers, researchers as well as graduate students who want to specialize in this field.

  4. Facilitering

    DEFF Research Database (Denmark)

    Ravn, Ib

    2012-01-01

    Facilitering (af latin facilis: gørbart, let at gøre) er den teknik at gøre det lettere for en forsamlet gruppe mennesker at udrette det, den ønsker. Facilitator er en slags mødeleder eller ordstyrer, der bistår gruppen ved at styre formen på deltagernes samtale og interaktion snarere end indholdet...

  5. A novel navigation template for fixation of acetabular posterior column fractures with antegrade lag screws: design and application.

    Science.gov (United States)

    Chen, Hongfen; Wang, Gang; Li, Runguang; Sun, Yongjian; Wang, Fuming; Zhao, Hui; Zhang, Peijun; Zhang, Xuanxuan

    2016-04-01

    To test whether a novel guide template we designed can facilitate accurate insertion of antegrade lag screws in the fixation of acetabular posterior column fractures. We created virtual three-dimensional reconstruction models of the pelvis from CT scan data obtained from 96 adult patients without any bony problems. A virtual cylindrical implant was placed along the longitudinal axis of the acetabular posterior column passing through the ischial tuberosity. The diameter of cylindrical implant was augmented to 6.5 mm, and the direction was adjusted until the optimal screw path was found using the reverse engineering technique. The orifice of this cylinder from the iliac fossa was determined as the entry point for the antegrade lag screw. The anatomical parameters of the screw entry path were measured and saved in .stl format. The guide template was designed according to the acetabular morphology and the measured anatomical parameters before it was put into manufacture of a solid template with the rapid prototyping technique. The feasibility and accuracy of the guide template were tested in cadaveric pelvises. Finally, the guide template was used in real surgery for five patients. Furthermore, the time required for surgery was recorded. Under the guide of this navigation template, antegrade lag screws were successfully placed in the posterior column of the acetabulum in the cadaveric test. And five lag screws were successfully placed in five patients. The mean time of antegrade lag screw insertion required 5.8 (3-10) min. Antegrade lag screws can be more accurately put into the posterior column of the acetabulum with the help of this navigation template.

  6. Mismatch analysis of humeral nailing. Antegrade versus retrograde insertion

    International Nuclear Information System (INIS)

    Mahaisavariya, B.; Jiamwatthanachai, P.; Aroonjarattham, P.; Aroonjarattham, K.; Wongcumchang, M.; Sitthiseripratip, K.

    2011-01-01

    Closed humeral nailing is now considered an alternative treatment for humeral-shaft fracture. The nail can be inserted with either the antegrade or retrograde method. We investigated and compared the problem of geometric mismatch of the humeral nail to the humerus between the two methods of insertion. The study was performed using virtual simulation based on computed tomography (CT) data of 76 Thai cadaveric humeri and the commonly used Russell-Taylor humeral nail 8 mm in diameter and 220 mm long. Mismatch of the nail to the intact humerus was analyzed and compared between the antegrade and retrograde nailing approaches. The results showed: the diameter of the medullary canal averaged 7.9-13.8 mm; the minimal reaming diameter to accommodate virtual nail insertion averaged 8.8-14.8 mm for the antegrade and 8.8-29.3 mm for the retrograde approach; the minimal reaming thickness of the inner cortex averaged 0.1-1.5 mm for the antegrade and 0.1-9.9 mm for the retrograde approach; the percentages of cortical bone removed prior to nail insertion were 3.8-107.1% and 3.8-1,287.6% for the antegrade and retrograde approaches, respectively; the eccentricity of the nail-medullary canal center were 0.4-3.4 and 0.4-10.6 mm for the antegrade and retrograde approaches, respectively. Less mismatching occurred with antegrade nailing than with the retrograde approach. Retrograde nailing requires excessive reaming at the distal part of the humerus to accommodate nail insertion. This may create bone weakness and the risk of supracondylar fracture. (author)

  7. Retrograde vs. Antegrade Puncture for Infra-Inguinal Angioplasty

    International Nuclear Information System (INIS)

    Nice, C.; Timmons, G.; Bartholemew, P.; Uberoi, R.

    2003-01-01

    This study was done to compare antegrade punctures with a retrograde puncture technique for infrainguinal angioplasty. A group of 100 consecutive patients (71 men, 29 women) were randomized for antegrade puncture or retrograde puncture of the common femoral artery. Following retrograde puncture the guidewire was 'turned' and placed into the superficial femoral artery. The time for gaining access, screening time, radiation dose, patient height, weight and complications were recorded. All patients were reviewed the day after the procedure and within 3 months. Data from 46 patients (34 males and 12 females) in the retrograde group and 44 (28 males and 16 females) in the antegrade group were available for analysis. Mean procedure time,screening time, radiation dose, height and weight were 8.3 minutes(range 3-22), 2.1 minutes (0.3-6.5), 7950 mGy cm -2 (820-71250), 169 cm (149-204) and 79 kg (32-108) for retrograde puncture and 8 min (2-60), 0.7 min (0.0-3.2), 1069 mGycm -2 (0-15400), 169 cm (152-186) and 75 kg (39-125) for antegrade punctures, respectively. An average of 1.2 (1-2) punctures was required for retrograde and 1.75 (1-8) for antegrade. Seven small hematomas occurred with antegrade and three for retrograde puncture.Retrograde puncture is technically easier with a tendency to fewer complications but results in a higher radiation dose. This technique should be used in difficult patients at high risk of haematoma formation

  8. Functional Outcomes of the Knee after Retrograde and Antegrade ...

    African Journals Online (AJOL)

    Background: Antegrade intramedullary nailing is currently considered the gold standard for treatment of femur shaft fractures although retrograde technique is gaining acceptance. Although introducing the nail through the knee has potential to damage the intra articular structures, several reports have indicated acceptable ...

  9. Percutaneous antegrade ureteric stent removal using a rigid alligator forceps.

    LENUS (Irish Health Repository)

    Given, M F

    2008-12-01

    To evaluate the safety and efficacy of percutaneous antegrade ureteric stent removal using a rigid alligator forceps. Twenty patients were included in our study. Indications for ureteric stent insertion included stone disease (n = 7), malignancy (n = 8) and transplant anastomotic strictures (n = 5). Stent retrieval was carried out for proximal stent placement\\/migration in seven patients and encrustation in the remaining 13. Twenty-two stents were successfully retrieved in 20 patients. There was one technical failure (5%). There were no major complications. We had four minor complications, which included nephrostomy site pain (n = 2), periprocedural sepsis (n = 1) and a small urinoma (n = 1). All patients settled with conservative management. Percutaneous radiologically guided antegrade ureteric stent removal with an alligator forceps is safe and effective, particularly when initial surgical removal has failed.

  10. Percutaneous nephrostomy and antegrade ureteral stenting: technique - indications - complications

    Energy Technology Data Exchange (ETDEWEB)

    Hausegger, Klaus A. [Klagenfurt General Hospital, Department of Radiology, Klagenfurt (Austria); Portugaller, Horst R. [University Hospital of Graz, Department of Radiology, Graz (Austria)

    2006-09-15

    In this review the technique, indication for and complications of percutaneous nephrostomy (PCN) and antegrade ureter stent insertion are described. In the majority of the cases PCN is performed to relieve urinary obstruction, which can be of benign or malignant nature. Another indication for PCN is for treatment of urinary fistulas. PCN can be performed under ultrasound and/or fluoroscopic guidance, with a success rate of more than 90%. The complication rate is approximately 10% for major and minor complications together and 4-5% for major complications only. Percutaneous antegrade double-J stent insertion usually is performed if retrograde ureter stenting has not been successful. However, especially in malignant obstructions, the success rate for antegrade stenting is higher than for retrograde transvesical double-J stent insertion. In the case of severe infection and bleeding after PCN JJ-stent insertion may be contraindicated so long as there is no sufficient concomitant drainage via a PCN. Lower urinary tract dysfunction should be excluded before stent placement. The complication rate is 2-4%. Consequent stent surveillance with regular stent exchange is mandatory. (orig.)

  11. Percutaneous nephrostomy and antegrade ureteral stenting: technique - indications - complications

    International Nuclear Information System (INIS)

    Hausegger, Klaus A.; Portugaller, Horst R.

    2006-01-01

    In this review the technique, indication for and complications of percutaneous nephrostomy (PCN) and antegrade ureter stent insertion are described. In the majority of the cases PCN is performed to relieve urinary obstruction, which can be of benign or malignant nature. Another indication for PCN is for treatment of urinary fistulas. PCN can be performed under ultrasound and/or fluoroscopic guidance, with a success rate of more than 90%. The complication rate is approximately 10% for major and minor complications together and 4-5% for major complications only. Percutaneous antegrade double-J stent insertion usually is performed if retrograde ureter stenting has not been successful. However, especially in malignant obstructions, the success rate for antegrade stenting is higher than for retrograde transvesical double-J stent insertion. In the case of severe infection and bleeding after PCN JJ-stent insertion may be contraindicated so long as there is no sufficient concomitant drainage via a PCN. Lower urinary tract dysfunction should be excluded before stent placement. The complication rate is 2-4%. Consequent stent surveillance with regular stent exchange is mandatory. (orig.)

  12. Treatment of humeral shaft fractures with antegrade intramedullary locking nail.

    Science.gov (United States)

    Tsourvakas, Stefanos; Alexandropoulos, Christos; Papachristos, Ioannis; Tsakoumis, Grigorios; Ameridis, Nikolaos

    2011-12-01

    Antegrade interlocked humeral nailing for stabilization of humeral fractures was introduced many years ago, and studies on this method in the orthopedic literature have shown mixed results. The purpose of this investigation was to document the clinical outcome and complications associated with the use of an antegrade intramedullary nail (T2, Stryker) for the humeral fractures. Between 2005 and 2008, 52 fractures of the humeral shaft were treated operatively with this intramedullary nail in our department. Eight patients were polytraumatized, and four patients had an open fracture. The mean age of patients was 51.7 years. Forty-eight patients had an adequate duration of clinical follow-up (a mean of 18 months) for analysis. Complications were recorded, and the time to union was measured. Shoulder and elbow functions were assessed using the Constant Score and the Morrey Score, respectively. Forty-six fractures healed, with a mean time to clinical union of 10.3 weeks. Two patients developed pseudarthroses. There were four adverse events: two proximal screws backed out, one superficial infection at the insertion point, and one fracture at the distal end of the nail. Ninety-one percentage of patients had an excellent or good shoulder function. Five further operations were necessary: two for treatment of pseudarthroses, two for removal the backed out proximal screws, and one wound debridement for superficial infection. Antegrade humeral nailing is a valid therapeutic option for stabilization of humeral shaft fractures. By strictly adhering to the operation technique, the number and the severity of complications can be reduced. When good fracture alignment and stability are obtained, uneventful bone healing with good functional results is the rule.

  13. Steering and evasion assist

    NARCIS (Netherlands)

    Dang, T.; Desens, J.; Franke, U.; Gavrila, D.; Schäfers, L.; Ziegler, W.; Eskandarian, A.

    2012-01-01

    Steering and evasion assistance defines a new and future class of driver assistance systems to avoid an impending collision with other traffic participants. Dynamic and kinematic considerations reveal that an evasive steering maneuver has high potential for collision avoidance in many driving

  14. Experimental temporal quantum steering

    Czech Academy of Sciences Publication Activity Database

    Bartkiewicz, K.; Černoch, Antonín; Lemr, K.; Miranowicz, A.; Nori, F.

    2016-01-01

    Roč. 6, Nov (2016), 1-8, č. článku 38076. ISSN 2045-2322 R&D Projects: GA ČR GAP205/12/0382 Institutional support: RVO:68378271 Keywords : temporal quantum steering * EPR steering Subject RIV: BH - Optics, Masers, Lasers Impact factor: 4.259, year: 2016

  15. Steering smog prediction

    NARCIS (Netherlands)

    R. van Liere (Robert); J.J. van Wijk (Jack)

    1997-01-01

    textabstractThe use of computational steering for smog prediction is described. This application is representative for many underlying issues found in steering high performance applications: high computing times, large data sets, and many different input parameters. After a short description of the

  16. Antegrade continence enemas in the management of intractable faecal incontinence.

    Science.gov (United States)

    Kiely, E M; Ade-Ajayi, N; Wheeler, R

    1995-01-01

    The introduction of the Malone procedure has improved the outlook for children with severe faecal incontinence. Phosphate and saline enemas are administered through the exteriorized appendix in antegrade fashion to achieve evacuation and ensure cleanliness. The appendix functions as a non-refluxing catheterizable channel: If it is not available for use, a tubularized caecal flap is a safe alternative. We have constructed Malone stomas using the appendix in 20 patients and another seven patients have undergone the caecal flap modification. The mean age was 8.6 years. Eleven of the patients were boys and 16 (59%) were girls. Six children required dilatation or revision of their stomas for stenosis. One developed small bowel obstruction and another has stopped using the stoma. The results of the continence enemas were considered to be very good by the vast majority of patients and their carers. Our recent experience suggests that bisacodyl may be a valuable adjunct to the antegrade enemas of phosphate and saline. We believe that this procedure may be extended with benefit to adults with serious faecal incontinence in whom standard measures have failed. PMID:7769583

  17. Steering Performance, Tactical Vehicles

    Science.gov (United States)

    2015-07-29

    break-in operation. d. The wheel toe, camber, and caster settings are within proper specifications for the test vehicle. e. The steering and...systems should be recorded. Particular characteristics of interest are as follows: a. Test location. b. Vehicle mileage. c. Camber, caster ...The inclination of a wheel outward from the body in the lateral plane. Caster The inclination of the steer rotation axis in the longitudinal plane

  18. Methodologies for steering clocks

    Science.gov (United States)

    Chadsey, Harold

    1995-01-01

    One of the concerns of the PTTI community is the coordination of one time scale with another. This is accomplished through steering one clock system to another, with a goal of a zero or constant offset in time and frequency. In order to attain this goal, rate differences are calculated and allowed for by the steering algorithm. This paper will present several of these different methods of determining rate differences. Ideally, any change in rate should not cause the offset to change sign (overshoot) by any amount, but certainly not by as much as its previous absolute value. The advantages and disadvantages of each depend on the user's situation.

  19. The use of a cutting balloon in contemporary reverse controlled antegrade and retrograde subintimal tracking (reverse CART) technique.

    Science.gov (United States)

    Nakabayashi, Keisuke; Okada, Hisayuki; Oka, Toshiaki

    2017-07-01

    The key concept of reverse controlled antegrade and retrograde tracking (CART) technique is retrograde puncture with a tapered wire to an antegrade balloon (contemporary reverse CART) or new connections between the antegrade and retrograde subintimal space (classical reverse CART). In our case, a 75-year-old man with severe chronic total occlusion of the right coronary artery, reverse CART with conventional balloons could not be accomplished. Externalization wiring was completed by contemporary reverse CART using a cutting balloon as an antegrade balloon to improve the fenestration force of the retrograde guidewire. Thus, the use of a cutting balloon for contemporary reverse CART might be promising.

  20. Distal femoral complications following antegrade intramedullary nail placement

    Directory of Open Access Journals (Sweden)

    Amanda J. Fantry

    2015-03-01

    Full Text Available While antegrade nailing for proximal and diaphyseal femur fractures is a commonly utilized fixation method with benefits including early mobilization and high rates of fracture union, both intraoperative and postoperative complications may occur. Intraoperative errors include leg length discrepancy, anterior cortical perforation, malreduction of the fracture, and neurovascular injury, and postoperative complications include nonunion, malunion, infection, and hardware failure. This case series reviews complications affecting the distal femur after intramedullary nailing including fracture surrounding a distal femoral interlocking screw (Case #1, nonunion after dynamization with nail penetration into the knee joint (Case #2, and anterior cortical perforation (Case #3. Prevention of intraoperative and postoperative complications surrounding intramedullary nailing requires careful study of the femoral anatomy and nail design specifications (radius of curvature, consideration of the necessity of distal interlocking screws, the need for close radiographic follow-up after nail placement with X-rays of the entire length of the nail, and awareness of possible nail penetration into the knee joint after dynamization.

  1. 49 CFR 570.60 - Steering system.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Steering system. 570.60 Section 570.60... 10,000 Pounds § 570.60 Steering system. (a) System play. Lash or free play in the steering system... excessive lash or free play in the steering system. Table 2. Steering Wheel Free Play Values Steering wheel...

  2. Predictors of antegrade flow at internal carotid artery during carotid artery stenting with proximal protection.

    Science.gov (United States)

    Harada, Kei; Kakumoto, Kosuke; Oshikata, Shogo; Fukuyama, Kozo

    2018-02-16

    Carotid artery stenting (CAS) with proximal occlusion effectively prevent distal cerebral embolism by flow arrest at internal carotid artery (ICA); however, the method can expose antegrade flow at ICA due to incomplete flow arrest. The aim of this study was to identify predictors of antegrade flow during CAS with proximal protection. We retrospectively analyzed clinical and angiographic data among 143 lesions treated with CAS with proximal protection by occluding the common carotid artery (CCA) and external carotid artery (ECA). Flow arrest or antegrade flow at ICA was confirmed by contrast injection during proximal protection. Antegrade flow at ICA was observed in 12 lesions (8.4%). Compared with lesions in which flow arrest of ICA was achieved, the diameter of the superior thyroid artery (STA) was significantly larger (2.4 ± 0.34 vs. 1.4 ± 0.68 mm, p flow. Distal filter protection should be combined with proximal protection for the lesions with antegrade flow to prevent distal migration of the carotid debris.

  3. Profunda Anchor Technique for Ipsilateral Antegrade Approach in Endovascular Treatment of Superficial Femoral Artery Ostial Occlusion

    International Nuclear Information System (INIS)

    Pua, Uei

    2015-01-01

    Endovascular treatment of the superficial femoral artery (SFA) is challenging in the presence of flush ostial occlusion. One of the main challenges is the availability of access sites for intervention. Contralateral retrograde femoral access followed by cross-over and antegrade intervention while commonly used, may not be feasible in cases of altered iliac anatomy (e.g. kissing iliac stents). Ipsilateral antegrade intervention using common femoral artery (CFA) access in these instances while possible is typically challenging due to inadequate working length of the CFA for interrogation of the SFA ostium, compounded by the lack of sheath stability. The “profunda anchor” technique uses a buddy wire in the profunda femoris artery (PFA) to stabilize the sheath and allow catheter manipulation for antegrade intervention at the level of the SFA ostium. The PFA is further used as a conduit for deployment of closure device to avoid interference with the treated SFA

  4. Profunda Anchor Technique for Ipsilateral Antegrade Approach in Endovascular Treatment of Superficial Femoral Artery Ostial Occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Pua, Uei, E-mail: druei@yahoo.com [Tan Tock Seng Hospital, Department of Diagnostic Radiology (Singapore)

    2015-04-15

    Endovascular treatment of the superficial femoral artery (SFA) is challenging in the presence of flush ostial occlusion. One of the main challenges is the availability of access sites for intervention. Contralateral retrograde femoral access followed by cross-over and antegrade intervention while commonly used, may not be feasible in cases of altered iliac anatomy (e.g. kissing iliac stents). Ipsilateral antegrade intervention using common femoral artery (CFA) access in these instances while possible is typically challenging due to inadequate working length of the CFA for interrogation of the SFA ostium, compounded by the lack of sheath stability. The “profunda anchor” technique uses a buddy wire in the profunda femoris artery (PFA) to stabilize the sheath and allow catheter manipulation for antegrade intervention at the level of the SFA ostium. The PFA is further used as a conduit for deployment of closure device to avoid interference with the treated SFA.

  5. Steering Your Mysterious Mind

    DEFF Research Database (Denmark)

    Prasad, Ramjee

    Steering the Mysterious Mind, describes a unique, novel concept for a way to gain control of your mind. The five basic elements of human life, that is; Creativity, Content­ment, Confidence, Calmness, and Concentration (C5) have been introduced in my previous book Unlock Your Personalization...... well-being is key for happy and stress free life. Mind has enormous energy. Everyone has access to tre­mendous mental energies; what matters is being aware of this and to work on concentrating your energy into creative work. To achieve mental strength, C5 is a su­preme powerful exercise for the mind....... Compare it with going to the gym where you work on the physical body. In the same way as with arms and legs, the mind is a mus­cle which you exercise through C5 practice. Steering the mind on your personal goal will help you to be creative....

  6. Outback catheter-assisted simultaneous antegrade and retrograde access for subintimal recanalization of peripheral arterial occlusion.

    Science.gov (United States)

    Bozlar, Ugur; Shih, Ming-Chen Paul; Harthun, Nancy L; Hagspiel, Klaus D

    2008-01-01

    Subintimal recanalization techniques have been shown to be beneficial in selected patients with severe peripheral vascular disease with tissue loss or rest pain and limited surgical options. In this report, we use an Outback catheter in order to gain access to the subintimal channel from the true lumen during percutaneous intentional extraluminal recanalization using the subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) technique. To the best of our knowledge, this is the first report where the Outback catheter was used in antegrade fashion in order to gain access to the subintimal space from the true lumen using the SAFARI technique.

  7. [Antegrade unilateral perfusion of the brain through the brachiocephalic trunk in operations on the aortic arch].

    Science.gov (United States)

    Kozlov, B N; Panfilov, D S; Kuznetsov, M S; Ponomarenko, I V; Nasrashvili, G G; Shipulin, V M

    2016-01-01

    Presented herein is a technique of unilateral antegrade perfusion of the brain in operations on the aortic arch. The method makes it possible to perform both systemic artificial circulation and adequate physiological perfusion of the brain, promoting minimization of the number of neurological complications.

  8. Surgical thromboendarterectomy for chronic thromboembolic pulmonary hypertension using circulatory arrest with selective antegrade cerebral perfusion

    NARCIS (Netherlands)

    Zeebregts, CJAM; Dossche, KM; Morshuis, WJ; Knaepen, PJ; Schepens, MAAM

    The use of circulatory arrest with selective antegrade cerebral perfusion is described in a 59-year-old man who underwent thrombendarterectomy for chronic thromboembolic pulmonary hypertension. The postoperative course was uneventful. The described surgical technique may prevent the patient from

  9. Steering Maps and Their Application to Dimension-Bounded Steering

    Science.gov (United States)

    Moroder, Tobias; Gittsovich, Oleg; Huber, Marcus; Uola, Roope; Gühne, Otfried

    2016-03-01

    The existence of quantum correlations that allow one party to steer the quantum state of another party is a counterintuitive quantum effect that was described at the beginning of the past century. Steering occurs if entanglement can be proven even though the description of the measurements on one party is not known, while the other side is characterized. We introduce the concept of steering maps, which allow us to unlock sophisticated techniques that were developed in regular entanglement detection and to use them for certifying steerability. As an application, we show that this allows us to go beyond even the canonical steering scenario; it enables a generalized dimension-bounded steering where one only assumes the Hilbert space dimension on the characterized side, with no description of the measurements. Surprisingly, this does not weaken the detection strength of very symmetric scenarios that have recently been carried out in experiments.

  10. A Novel Risk Score in Predicting Failure or Success for Antegrade Approach to Percutaneous Coronary Intervention of Chronic Total Occlusion: Antegrade CTO Score.

    Science.gov (United States)

    Namazi, Mohammad Hasan; Serati, Ali Reza; Vakili, Hosein; Safi, Morteza; Parsa, Saeed Ali Pour; Saadat, Habibollah; Taherkhani, Maryam; Emami, Sepideh; Pedari, Shamseddin; Vatanparast, Masoomeh; Movahed, Mohammad Reza

    2017-06-01

    Total occlusion of a coronary artery for more than 3 months is defined as chronic total occlusion (CTO). The goal of this study was to develop a risk score in predicting failure or success during attempted percutaneous coronary intervention (PCI) of CTO lesions using antegrade approach. This study was based on retrospective analyses of clinical and angiographic characteristics of CTO lesions that were assessed between February 2012 and February 2014. Success rate was defined as passing through occlusion with successful stent deployment using an antegrade approach. A total of 188 patients were studied. Mean ± SD age was 59 ± 9 years. Failure rate was 33%. In a stepwise multivariate regression analysis, bridging collaterals (OR = 6.7, CI = 1.97-23.17, score = 2), absence of stump (OR = 5.8, CI = 1.95-17.9, score = 2), presence of calcification (OR = 3.21, CI = 1.46-7.07, score = 1), presence of bending (OR = 2.8, CI = 1.28-6.10, score = 1), presence of near side branch (OR = 2.7, CI = 1.08-6.57, score = 1), and absence of retrograde filling (OR = 2.5, CI = 1.03-6.17, score = 1) were independent predictors of PCI failure. A score of 7 or more was associated with 100% failure rate whereas a score of 2 or less was associated with over 80% success rate. Most factors associated with failure of CTO-PCI are related to lesion characteristics. A new risk score (range 0-8) is developed to predict CTO-PCI success or failure rate during antegrade approach as a guide before attempting PCI of CTO lesions.

  11. Antegrade flexible ureteroscopy in supine position for impacted multiple ureteric calculi

    Directory of Open Access Journals (Sweden)

    Rahul Gupta

    2006-01-01

    Full Text Available Flexible retrograde ureteroscope is now being widely used in endoscopic management of the urinary calculi. We report technique of supine ante grade flexible ureteroscopy in treating impacted upper and mid ureteric calculi in a pediatric patient. A six year-old boy with a history of acute right ureteric colic was investigated and found to have right upper and middle impacted ureteric calculi. He was planned for ureteroscopy, but the intramural part of the ureter could not be dilated. Hence, a decision was taken to do an antegrade flexible ureteroscopy in the supine position. An antegrade renal access was established in the supine position using ultrasound- guided puncture, a 22 Fr Amplatz was placed after serial dilatation of the tract and the stones were accessed using a flexible ureteroscope. The stones were then disintegrated using holmium laser. The ureter was stented at the end of the procedure. IVU done after six months revealed normal right kidney.

  12. STEER Coastal Use Mapping Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Use Mapping Project is designed to collect critical information on human activities in and near the St. Thomas East End Reserves (STEER). The project...

  13. Retrograde or antegrade double-pigtail stent placement for malignant ureteric obstruction?

    International Nuclear Information System (INIS)

    Uthappa, M.C.; Cowan, N.C.

    2005-01-01

    AIM: To determine the optimum approach for double-pigtail stent placement in malignant ureteric obstruction. PATIENTS AND METHODS: Retrograde stent placement was attempted in a consecutive series of patients presenting with malignant ureteric obstruction. If retrograde stent placement was unsuccessful, percutaneous nephrostomy was performed immediately followed by elective antegrade stent placement. Identical digital C-arm fluoroscopy for image-guidance and conditions for anaesthesia and analgesia were employed for both retrograde and antegrade procedures. Identical 8 Fr (20-26 cm) double-pigtail hydrophilic coated stents were used for each approach. RESULTS: Retrograde placement was attempted in 50 ureters in 30 patients {19 male, 11 female, average age 61.4 yr (range 29-90 yr)} over a 24-month period. The success rate for retrograde ureteric stent placement was 50% (n=25/50). Technical failures were due to failure to identify the ureteric orifice (n=22), failure to cross the stricture (n=1), failure to pass the stent (n=1) and failure to pass a 4 Fr catheter (n=1). Antegrade placement was attempted in 25 ureters with a success rate of 96% (n=24/25). Failure in the one case was due to inability to cross an upper third stricture secondary to pyeloureteritis cystica. CONCLUSION: It is suggested that retrograde route should be the initial approach if imaging shows no involvement of ureteric orifice (UO), when nephrostomy is technically very difficult or in cases of solitary kidney. The antegrade route is preferred if imaging shows tumour occlusion of the UO or if there is a tight stricture very close to the uretero-vesical junction (UVJ) making purchase within the ureter difficult for crossing the stricture

  14. Laparoscopic common bile duct exploration and antegrade biliary stenting: Leaving behind the Kehr tube

    Directory of Open Access Journals (Sweden)

    Darío Martínez-Baena

    2013-03-01

    Full Text Available Introduction: single-stage laparoscopic surgery of cholelithiasis and associated common bile duct stones (CL-CBDS has shown similar results when compared to laparoscopic cholecystectomy combined with ERCP. Classically, choledochorrhaphy has been protected by a T-tube drain to allow external bypass of bile flow. However, its removal is associated with a significant complication rate. Use of antegrade biliary stents avoids T-tube removal associated morbidity. The aim of this study is to compare the results of choledochorrhaphy plus T-tube drainage versus antegrade biliary stenting in our series of laparoscopic common bile duct explorations (LCBDE. Material and methods: between 2004 and 2011, 75 patients underwent a LCBDE. Choledochorrhaphy was performed following Kehr tube placements in 47 cases and transpapillary biliary stenting was conducted in the remaining 28 patients. Results: postoperative hospital stay was shorter in the stent group (5 ± 10.26 days than in the Kehr group (12 ± 10.6 days, with a statistically significant difference. There was a greater trend to grade B complications in the stent group (10.7 vs. 4.3 % and to grade C complications in the Kehr group (6.4 vs. 3.6 %. There were 3 cases of residual common bile duct stones in the Kehr group (6.4 % and none in the stent group. Conclusions: antegrade biliary stenting following laparoscopic common bile duct exploration for CL-CBDS is an effective and safe technique that prevents T-tube related morbidity.

  15. Moderate Versus Deep Hypothermia With Unilateral Selective Antegrade Cerebral Perfusion for Acute Type A Dissection.

    Science.gov (United States)

    Leshnower, Bradley G; Thourani, Vinod H; Halkos, Michael E; Sarin, Eric L; Keeling, William B; Lamias, Mark J; Guyton, Robert A; Chen, Edward P

    2015-11-01

    Despite improved results with surgical therapy for acute type A aortic dissection (ATAAD), there remains a lack of consensus regarding the optimal method of cerebral protection and circulation management during ATAAD. The purpose of this study is to determine whether in the setting of antegrade cerebral perfusion, moderate hypothermic circulatory arrest (MHCA) provides equivalent cerebral and visceral protection as deep hypothermic circulatory arrest (DHCA) for patients undergoing emergent ATAAD repair. A review of the Emory aortic surgery database from 2004 to 2014 identified 288 patients who underwent ATAAD with right axillary artery cannulation, unilateral selective antegrade cerebral perfusion (uSACP), and hypothermic circulatory arrest (HCA). In all, 88 patients underwent HCA at 24 °C or lower (DHCA), and 206 patients underwent HCA at more than 24 °C (MHCA). Major adverse outcomes of death, stroke, temporary neurologic dysfunction, and dialysis-dependent renal failure were examined. The groups were well matched for age and major comorbidities. The DHCA patients underwent HCA at lower temperatures (DHCA 21.6 ± 3.1 °C vs MHCA 27.4 ± 1.6 °C, p 0.05). Moderate HCA with uSACP is an effective circulation management strategy that provides excellent cerebral and visceral protection during emergent ATAAD repair. In the setting of antegrade cerebral perfusion, deep hypothermia does not provide any additional benefit. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Exoseal for puncture site closure after antegrade procedures in peripheral arterial disease patients.

    Science.gov (United States)

    Hackl, Gerald; Gary, Thomas; Belaj, Klara; Hafner, Franz; Rief, Peter; Deutschmann, Hannes; Brodmann, Marianne

    2014-01-01

    Exoseal is a vascular clo-sure device consisting of a plug applier and a bio-absorbent polyglycolic acid plug available in sizes 5 F, 6 F, and 7 F. In this study, we aimed to evaluate the effectiveness and safety of the Exoseal vascular closure device (Cordis Corporation, Bridgewater, New Jersey, USA) for puncture site closure after antegrade endovascular procedures in peripheral arterial occlusive disease (PAOD) patients. In this retrospective study, a total of 168 consecutive patients who underwent an interventional procedure due to PAOD, were included. In each case, an antegrade peripheral endovascular procedure was performed via the common femoral artery using the Seldinger technique, and Exoseal 5 F, 6 F, or 7 F was used for access site closure. The primary endpoint was a technically successful application of Exoseal. All complications at the access site within 24 hours were registered as a secondary endpoint. In a group of 168 patients (64.9% men, average age 71.9±11.9 years), the technical application of Exoseal was successful in 166 patients (98.8%). Within the first 24 hours after the procedure, 12 complications (7.2%) were recorded including, three pseudoaneurysms (1.8%) and nine hematomas (5.4%). None of the complications required surgical intervention. Exoseal is a safe and effective device with high technical success and acceptable complication rates for access site closure after antegrade peripheral endovascular procedures.

  17. A Parallel and Distributed Surrogate Model Implementation for Computational Steering

    KAUST Repository

    Butnaru, Daniel

    2012-06-01

    Understanding the influence of multiple parameters in a complex simulation setting is a difficult task. In the ideal case, the scientist can freely steer such a simulation and is immediately presented with the results for a certain configuration of the input parameters. Such an exploration process is however not possible if the simulation is computationally too expensive. For these cases we present in this paper a scalable computational steering approach utilizing a fast surrogate model as substitute for the time-consuming simulation. The surrogate model we propose is based on the sparse grid technique, and we identify the main computational tasks associated with its evaluation and its extension. We further show how distributed data management combined with the specific use of accelerators allows us to approximate and deliver simulation results to a high-resolution visualization system in real-time. This significantly enhances the steering workflow and facilitates the interactive exploration of large datasets. © 2012 IEEE.

  18. Fermilab Steering Group Report

    Energy Technology Data Exchange (ETDEWEB)

    Beier, Eugene; /Pennsylvania U.; Butler, Joel; /Fermilab; Dawson, Sally; /Brookhaven; Edwards, Helen; /Fermilab; Himel, Thomas; /SLAC; Holmes, Stephen; /Fermilab; Kim, Young-Kee; /Fermilab /Chicago U.; Lankford, Andrew; /UC, Irvine; McGinnis, David; /Fermilab; Nagaitsev, Sergei; /Fermilab; Raubenheimer, Tor; /SLAC /Fermilab

    2007-01-01

    The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOVA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building an intense proton facility, Project X, consisting of a linear accelerator with the currently planned characteristics of the ILC combined with Fermilab's existing Recycler Ring and the Main Injector accelerator. The major component of Project X is the linac. Cryomodules, radio-frequency distribution, cryogenics and instrumentation for the linac are the same as or similar to those used in the ILC at a scale of about one percent of a full ILC linac. Project X's intense proton beams would open a path to discovery in neutrino science and in precision physics with charged leptons and quarks. World-leading experiments would allow physicists to address key questions of the Quantum Universe: How did the universe come to be? Are there undiscovered principles of nature: new symmetries, new physical laws? Do all the particles and forces become one? What happened to the antimatter? Building Project X's ILC-like linac would offer substantial support for ILC development by accelerating the

  19. Use of Antegrade Continence Enema for the Treatment of Fecal Incontinence and Functional Constipation in Adults: A Systematic Review.

    Science.gov (United States)

    Patel, Abhilasha S; Saratzis, Athanasios; Arasaradnam, Ramesh; Harmston, Christopher

    2015-10-01

    Antegrade continence enema is a proximal colonic stoma that allows antegrade lavage of the colon for the treatment of fecal incontinence and functional constipation. Its role in the treatment of these conditions in adults has not been established. This review aimed to evaluate the clinical response and complications of antegrade continence enema in the adult population. A systematic literature search of MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases from January 1980 to October 2013 was conducted. Studies reporting clinical outcomes of antegrade continence enema in adult patients were considered. Only studies with participants aged 16 years and older were selected. Use of the antegrade continence enema for the treatment of constipation and incontinence in adults was investigated. The primary outcome was the number of patients irrigating their stoma. Secondary outcomes included the incidence of stoma stenosis, assessment of functional outcome, and evaluation of quality of life. Overall, 15 studies were selected, describing outcomes in 374 patients. All of the reports were observational cross-sectional studies, and 4 were prospective. The number of participants still using their stoma ranged from 47% to 100% over a follow-up period of 6 to 55 months. Eleven studies reported achievement of full continence in 33% to 100% of patients. Four studies described functional outcomes, and 7 studies reported a wide range of patient satisfaction. The rate of stoma stenosis varied from 8% to 50%. There were considerable heterogeneities within and across studies. Most studies were of poor quality, as reflected in the Methodological Index for Nonrandomized Studies score. Antegrade continence enema has been reported as an acceptable treatment of both functional constipation and fecal incontinence in adults across several analyses. There is wide variation regarding outcome measures. Larger prospective studies are required to assess the role of antegrade

  20. Driver steering model for closed-loop steering function analysis

    Science.gov (United States)

    Bolia, Pratiksh; Weiskircher, Thomas; Müller, Steffen

    2014-05-01

    In this paper, a two level preview driver steering control model for the use in numerical vehicle dynamics simulation is introduced. The proposed model is composed of cascaded control loops: The outer loop is the path following layer based on potential field framework. The inner loop tries to capture the driver's physical behaviour. The proposed driver model allows easy implementation of different driving situations to simulate a wide range of different driver types, moods and vehicle types. The expediency of the proposed driver model is shown with the help of developed driver steering assist (DSA) function integrated with a conventional series production (Electric Power steering System with rack assist servo unit) system. With the help of the DSA assist function, the driver is prevented from over saturating the front tyre forces and loss of stability and controllability during cornering. The simulation results show different driver reactions caused by the change in the parameters or properties of the proposed driver model if the DSA assist function is activated. Thus, the proposed driver model is useful for the advanced driver steering and vehicle stability assist function evaluation in the early stage of vehicle dynamics handling and stability evaluation.

  1. Dual Antegrade Intramedullary Headless Screw Fixation for Treatment of Unstable Proximal Phalanx Fractures.

    Science.gov (United States)

    Gaspar, Michael P; Gandhi, Shiv D; Culp, Randall W; Kane, Patrick M

    2018-01-01

    Although intramedullary headless screw (IMHS) fixation is a promising minimally invasive surgical treatment option for unstable proximal phalanx fractures, a single IMHS may provide inadequate fixation for certain fracture patterns. The purpose of this study was to evaluate the short-term clinical outcomes in a pilot series of patients with proximal phalanx fractures treated with dual antegrade IMHS fixation. We performed a retrospective chart review of proximal phalanx fractures treated with dual antegrade IMHS fixation with a minimum 1 year of follow-up. Demographic information including patient age, sex, occupation, workers' compensation status, mechanism of injury, hand dominance, and injured digit were obtained. Postoperative outcomes measured included range of motion, grip strength, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) outcome scores, return to full-duty work interval, and complications. Ten fractures in 10 patients (4 male, 6 female) satisfied study inclusion. The mean age of patients was 39 years (range, 20-62), and average follow-up duration was 84 weeks (range, 61-106). Final postoperative total active motion was 258° (range, 245°-270°), mean grip strength was 97% (range, 84%-104%) of the uninjured side, and QuickDASH score was 3.9 (range, 0-13.6). No complications occurred, and no patients required additional intervention. Dual antegrade IMHS fixation of proximal phalanx fractures resulted in excellent postoperative motion, near-normal grip strength, positive self-reported patient outcomes, and no complications with follow-up of at least 1 year. Further study in a larger number of patients is warranted to determine if this promising technique is superior to other modes of fixation.

  2. Sacral nerve stimulation allows for decreased antegrade continence enema use in children with severe constipation.

    Science.gov (United States)

    Lu, Peter L; Asti, Lindsey; Lodwick, Daniel L; Nacion, Kristine M; Deans, Katherine J; Minneci, Peter C; Teich, Steven; Alpert, Seth A; Yacob, Desale; Di Lorenzo, Carlo; Mousa, Hayat M

    2017-04-01

    Sacral nerve stimulation (SNS) can be beneficial for children with constipation, but no studies have focused on children with constipation severe enough to require antegrade continence enemas (ACEs). Our objective was to evaluate the efficacy of SNS in children with constipation treated with ACE. Using a prospective patient registry, we identified patients constipation dependent on ACE, SNS led to a steady decrease in ACE usage with nearly half of patients receiving cecostomy/appendicostomy closure within 2years. IV. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Experimental verification of multidimensional quantum steering

    Science.gov (United States)

    Li, Che-Ming; Lo, Hsin-Pin; Chen, Liang-Yu; Yabushita, Atsushi

    2018-03-01

    Quantum steering enables one party to communicate with another remote party even if the sender is untrusted. Such characteristics of quantum systems not only provide direct applications to quantum information science, but are also conceptually important for distinguishing between quantum and classical resources. While concrete illustrations of steering have been shown in several experiments, quantum steering has not been certified for higher dimensional systems. Here, we introduce a simple method to experimentally certify two different kinds of quantum steering: Einstein-Podolsky-Rosen (EPR) steering and single-system (SS) steering (i.e., temporal steering), for dimensionality (d) up to d = 16. The former reveals the steerability among bipartite systems, whereas the latter manifests itself in single quantum objects. We use multidimensional steering witnesses to verify EPR steering of polarization-entangled pairs and SS steering of single photons. The ratios between the measured witnesses and the maximum values achieved by classical mimicries are observed to increase with d for both EPR and SS steering. The designed scenario offers a new method to study further the genuine multipartite steering of large dimensionality and potential uses in quantum information processing.

  4. Demand side management using profile steering

    NARCIS (Netherlands)

    Gerards, Marco Egbertus Theodorus; Toersche, Hermen; Hoogsteen, Gerwin; van der Klauw, Thijs; Hurink, Johann L.; Smit, Gerardus Johannes Maria

    2015-01-01

    Many Demand Side Management (DSM) approaches use energy prices as steering signals. This paper shows that such steering signals may result in power quality problems and high losses. As an alternative, this paper proposes to use desired (e.g., flat) power profiles as steering signals and presents an

  5. Multi-Layer Traffic Steering

    DEFF Research Database (Denmark)

    Fotiadis, Panagiotis; Polignano, Michele; Gimenez, Lucas Chavarria

    2013-01-01

    This paper investigates the potentials of traffic steering in the Radio Resource Control (RRC) Idle state by evaluating the Absolute Priorities (AP) framework in a multilayer Long Term Evolution (LTE) macrocell scenario. Frequency priorities are broadcast on the system information and RRC Idle...

  6. Tips and tricks for antegrade recanalization of chronic total occlusions using the CrossBoss catheter.

    Science.gov (United States)

    Kwan, Tak W; Diwan, Ravi; Ratcliffe, Justin A; Huang, Yili; Patri, Rahul; James, David; Liou, Michael; Fallahi, Arzhang; Young, Bruce; Nanjundappa, Aravinda; Daggubati, Ramesh

    2015-02-01

    To provide new strategies and techniques for the successful recanalization of chronic total occlusions (CTOs) with the sole use of the CrossBoss catheter. In addition, some common CTO scenarios are illustrated in detail. CTOs are one of the most challenging complex coronary lesion subsets to intervene upon. Even with the innovation of specialized catheters, the success rate of antegrade recanalization remains low. Between June and December 2013, a retrospective analysis of 50 consecutive patients who presented with a planned percutaneous intervention (PCI) of a CTO was performed. In all patients, the CrossBoss catheter was used. No additional reentry devices were necessary. Procedural success was defined as failure. The average fluoroscopy time was 45.9 minutes and the average amount of contrast use was 273.8 mL. No patient suffered a coronary perforation from the CrossBoss catheter. With increased experience using the CrossBoss catheter, the antegrade success rate of CTOs can be improved. Some tips include identifying the likely course of the artery with the aid of retrograde injection, proper guidewire selection and manipulation, and redirecting the CrossBoss catheter if there is substantial deviation from the original path.

  7. Functional Outcome After Antegrade Femoral Nailing : A Comparison of Trochanteric Fossa Versus Tip of Greater Trochanter Entry Point

    NARCIS (Netherlands)

    Moein, Chloe Ansari; ten Duis, Henk-Jan; Oey, Liam; de Kort, Gerard; van der Meulen, Wout; Vermeulen, Karin; van der Werken, Christiaan

    Objectives: This study was performed to explore the relationship between entry point-related soft tissue damage in antegrade femoral nailing and the functional outcome in patients with a proximal third femoral shaft fracture. Design: Retrospective clinical trial. Setting: Level I university trauma

  8. Retrograde endovenous laser ablation through saphenopopliteal junctional area for incompetent small saphenous vein; Comparison with antegrade approach

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Seok; Park, Sang Woo; Yun, Ik Jin; Hwang, Jae Joon; Lee, Song Am; Chee, Hyun Keun; Hwang, Jin Ho [Konkuk University Hospital, Konkuk University School of Medicine, Seoul (Korea, Republic of)

    2016-06-15

    To evaluate the safety and efficacy of retrograde endovenous laser ablation (EVLA) and to compare it with the conventional antegrade EVLA for incompetent small saphenous vein (SSV). Small saphenous vein was cannulated via two approaches under ultrasound-guidance. One method involved puncturing the SSV cranially at mid-calf (the antegrade group). If the antegrade puncture into the SSV failed twice, the other approach for puncture was selected that involved puncturing the SSV toward the ankle (the retrograde group). Patients were evaluated in terms of technical and clinical success, closure rates of the SSV, and complications including pain, bruising, or paresthesia at all follow-up visits. The 1470 nm endovenous laser was used in all limbs. Technical success was seen in all limbs in both groups (100%). Closure rate in both groups showed about 95%, without significant difference (p = 0.685). Similar linear endovenous energy density was supplied during the EVLA in both groups (p = 0.876). Three frequent complications including bruising, pain, and paresthesia did not show statistical significance between groups (p = 0.465, 0.823, 1.000, respectively). Major complications were absent in both groups. The EVLA for the incompetent SSV using a retrograde approach is safe and effective and should be considered the alternative method if the antegrade access fails due to vasospasm or small SSV diameter.

  9. Retrograde endovenous laser ablation through saphenopopliteal junctional area for incompetent small saphenous vein; Comparison with antegrade approach

    International Nuclear Information System (INIS)

    Kim, Jun Seok; Park, Sang Woo; Yun, Ik Jin; Hwang, Jae Joon; Lee, Song Am; Chee, Hyun Keun; Hwang, Jin Ho

    2016-01-01

    To evaluate the safety and efficacy of retrograde endovenous laser ablation (EVLA) and to compare it with the conventional antegrade EVLA for incompetent small saphenous vein (SSV). Small saphenous vein was cannulated via two approaches under ultrasound-guidance. One method involved puncturing the SSV cranially at mid-calf (the antegrade group). If the antegrade puncture into the SSV failed twice, the other approach for puncture was selected that involved puncturing the SSV toward the ankle (the retrograde group). Patients were evaluated in terms of technical and clinical success, closure rates of the SSV, and complications including pain, bruising, or paresthesia at all follow-up visits. The 1470 nm endovenous laser was used in all limbs. Technical success was seen in all limbs in both groups (100%). Closure rate in both groups showed about 95%, without significant difference (p = 0.685). Similar linear endovenous energy density was supplied during the EVLA in both groups (p = 0.876). Three frequent complications including bruising, pain, and paresthesia did not show statistical significance between groups (p = 0.465, 0.823, 1.000, respectively). Major complications were absent in both groups. The EVLA for the incompetent SSV using a retrograde approach is safe and effective and should be considered the alternative method if the antegrade access fails due to vasospasm or small SSV diameter

  10. Multiobjective optimization of a steering linkage

    International Nuclear Information System (INIS)

    Sleesonsom, S.; Bureerat, S.

    2016-01-01

    In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria

  11. Multiobjective optimization of a steering linkage

    Energy Technology Data Exchange (ETDEWEB)

    Sleesonsom, S.; Bureerat, S. [Sustainable and Infrastructure Research and Development Center, Dept. of Mechanical Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen (Thailand)

    2016-08-15

    In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria.

  12. Thoracic aortic cannulation with antegrade perfusion for the procurement of abdominal organs.

    Science.gov (United States)

    González Rodríguez, Francisco Javier; Fernández Pérez, Aquilino; Conde Freire, Rogelio; Martínez, Jorge; Pérez, Evaristo Varo; Bustamante Montalvo, Manuel

    2015-01-01

    The definitive acceptance of an organ as valid for transplant depends on the surgical team performing the multiorgan recovery; and unexpected difficulties can occur. The demographic characteristics of donors has changed, and some accepted donors can present difficulties in surgical technique and risky decisions on the validity of the retrieved organ or organs. An alternative method to the cannulation of the abdominal aorta is proposed when there is evidence of disease in the infrarenal aorta during the multiorgan procurement. The retrocardiac descending thoracic aorta is cannulated using an antegrade perfusion; this technique allows an increase in organ recovery. Copyright © 2014 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Hybrid aortic repair with antegrade supra-aortic and renovisceral debranching from ascending aorta.

    Science.gov (United States)

    Del Castro-Madrazo, José Antonio; Rivas-Domínguez, Margarita; Fernández-Prendes, Carlota; Zanabili Al-Sibbai, Amer; Llaneza-Coto, José Manuel; Alonso-Pérez, Manuel

    2017-05-01

    Aortic dissection is a life threatening condition. Hybrid repair has been described for the treatment of complex aortic pathology such as thoracoabdominal aortic aneurysms (TAAA) and type A and B dissections, although open and total endovascular repair are also possible. Open surgery is still associated with substantial perioperative morbi-mortality rates, thus less invasive techniques such as endovascular repair and hybrid procedures can achieve good results in centers with experience. We present the case of a patient with a chronic type B dissection and TAAA degeneration that was treated in a single stage hybrid procedure with antegrade supra-aortic and renovisceral debranching from the ascending aorta and TEVAR. At three-year follow up, the patient is free of intervention-related complications.

  14. The female geriatric proximal humeral fracture: protagonist for straight antegrade nailing?

    Science.gov (United States)

    Lindtner, Richard A; Kralinger, Franz S; Kapferer, Sebastian; Hengg, Clemens; Wambacher, Markus; Euler, Simon A

    2017-10-01

    Straight antegrade humeral nailing (SAHN) has become a standard technique for the surgical fixation of proximal humeral fractures, which predominantly affect elderly females. The nail's proximal anchoring point has been demonstrated to be critical to ensure reliable fixation in osteoporotic bone and to prevent iatrogenic damage to the superior rotator cuff bony insertion. Anatomical variations of the proximal humerus, however, may preclude satisfactory anchoring of the nail's proximal end and may bare the risk of rotator cuff violation, even though the nail is inserted as recommended. The aim of this study was to evaluate the anatomical suitability of proximal humeri of geriatric females aged 75 years and older for SAHN. Specifically, we sought to assess the proportion of humeri not anatomically amenable to SAHN for proximal humeral fracture. A total of 303 proximal humeri of 241 females aged 75 years and older (mean age 84.5 ± 5.0 years; range 75-102 years) were analyzed for this study. Multiplanar two-dimensional reformations (true ap, true lateral, and axial) were reconstructed from shoulder computed tomography (CT) data sets. The straight antegrade nail's ideal entry point, "critical point" (CP), and critical distance (CD; distance between ideal entry point and CP) were determined. The rate of proximal humeri not anatomically suitable for SAHN (critical type) was assessed regarding proximal reaming diameters of currently available straight antegrade humeral nails. Overall, 35.6% (108/303) of all proximal humeri were found to be "critical types" (CD straight antegrade nails currently in use. Moreover, 43.2% (131/303) of the humeri were considered "critical types" with regard to the alternatively used larger proximal reaming diameter of 11.5 mm. Mean CD was 9.0 ± 1.7 mm (range 3.5-13.5 mm) and did not correlate with age (r = -0.04, P = 0.54). No significant differences in CD and rate of "critical types" were found between left and right humeri

  15. Hypothermia and Selective Antegrade Cerebral Perfusion Is Safe for Arch Repair in Type A Dissection.

    Science.gov (United States)

    Keeling, W Brent; Leshnower, Bradley G; Hunting, John C; Binongo, Jose; Chen, Edward P

    2017-09-01

    Unilateral selective antegrade cerebral perfusion with moderate hypothermic circulatory arrest has been shown to be a safe and effective method of cerebral protection during surgery for acute type A dissection. This study evaluates the impact of this cerebral protection strategy on clinical outcomes after extended aortic arch reconstruction in patients undergoing emergent repair of acute type A dissection. A retrospective review from 2004 to 2016 at a US academic center of patients undergoing surgery for acute type A dissections using moderate hypothermic circulatory arrest and selective antegrade cerebral perfusion was performed. Patient data were abstracted from The Society of Thoracic Surgeons (STS) institutional database and patient charts. Cohorts were established based on extent of arch replacement: a hemiarch group and a transverse arch group were created. Owing to a dearth of events, a risk score was estimated using a logistic regression model with 30-day mortality as outcome and preoperative variables as predictors, including non-STS variables such as malperfusion. Postoperative outcomes were then adjusted in subsequent regression analyses for the estimated risk score. In all, 342 patients met inclusion criteria and were included for analysis (299 hemiarch, 43 transverse arch). The mean age was 55.4 years and not different between groups (p = 0.79). Preoperative comorbidities, including prior stroke, diabetes mellitus, and renal failure, were also similar between groups (p > 0.2). Inhospital mortality was 11.7% for the entire cohort (11.7% hemiarch, 9.3% transverse arch; p = 0.60), and the permanent stroke rate was 7.3% (7.7% hemiarch, 4.3% transverse arch; p = 0.47). Median circulatory arrest time was 38.9 ± 19.2 minutes (35.0 ± 13.2 hemiarch, 65.1 ± 30.1 transverse arch; p optimal strategy for cerebral protection in this acute setting. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Is the Routine Check Nephrostogram Following Percutaneous Antegrade Ureteric Stent Placement Necessary?

    International Nuclear Information System (INIS)

    Soh, Keng Chuan; Tay, Kiang Hiong; Tan, Bien Soo; MM Htoo, Austin; HG Lo, Richard; Lin, Shueh En

    2008-01-01

    Our aim was to review our experience with percutaneous antegrade ureteric stent (PAUS) placement and to determine if the routinely conducted check nephrostogram on the day following ureteric stent placement was necessary. Retrospective review of patients who had undergone PAUS placement between January 2004 and December 2005 was performed. There were 83 subjects (36 males, 47 females), with a mean age of 59.9 years (range, 22-94 years). Average follow-up duration was 7.1 months (range, 1-24 months). The most common indications for PAUS placement were ureteric obstruction due to metastatic disease (n = 56) and urinary calculi (n = 34). Technical success was 93.2% (96/103 attempts), with no major immediate procedure-related complications or mortalities. The Bard 7Fr Urosoft DJ Stent was used in more than 95% of the cases. Eighty-one of 89 (91.0%) check nephrostograms demonstrated a patent ureteric stent with resultant safety catheter removal. Three check nephrostograms revealed distal stent migration requiring repositioning by a goose-snare, while five others showed stent occlusion necessitating permanent external drainage by nephrostomy drainage catheter reinsertion. Following PAUS placement, the serum creatinine level improved or stabilized in 82% of patients. The serum creatinine outcome difference between the groups with benign and malignant indications for PAUS placement was not statistically significant (p = 0.145) but resolution of hydronephrosis was significantly better (p = 0.008) in patients with benign indications. Percutaneous antegrade ureteric stent placement is a safe and effective means of relief for ureteric obstruction. The check nephrostogram following ureteric stent placement was unnecessary in the majority of patients

  17. Three-bead steering microswimmers

    Science.gov (United States)

    Rizvi, Mohd Suhail; Farutin, Alexander; Misbah, Chaouqi

    2018-02-01

    The self-propelled microswimmers have recently attracted considerable attention as model systems for biological cell migration as well as artificial micromachines. A simple and well-studied microswimmer model consists of three identical spherical beads joined by two springs in a linear fashion with active oscillatory forces being applied on the beads to generate self-propulsion. We have extended this linear microswimmer configuration to a triangular geometry where the three beads are connected by three identical springs in an equilateral triangular manner. The active forces acting on each spring can lead to autonomous steering motion; i.e., allowing the swimmer to move along arbitrary paths. We explore the microswimmer dynamics analytically and pinpoint its rich character depending on the nature of the active forces. The microswimmers can translate along a straight trajectory, rotate at a fixed location, as well as perform a simultaneous translation and rotation resulting in complex curved trajectories. The sinusoidal active forces on the three springs of the microswimmer contain naturally four operating parameters which are more than required for the steering motion. We identify the minimal operating parameters which are essential for the motion of the microswimmer along any given arbitrary trajectory. Therefore, along with providing insights into the mechanics of the complex motion of the natural and artificial microswimmers, the triangular three-bead microswimmer can be utilized as a model for targeted drug delivery systems and autonomous underwater vehicles where intricate trajectories are involved.

  18. Wireless traffic steering for green cellular networks

    CERN Document Server

    Zhang, Shan; Zhou, Sheng; Niu, Zhisheng; Shen, Xuemin (Sherman)

    2016-01-01

    This book introduces wireless traffic steering as a paradigm to realize green communication in multi-tier heterogeneous cellular networks. By matching network resources and dynamic mobile traffic demand, traffic steering helps to reduce on-grid power consumption with on-demand services provided. This book reviews existing solutions from the perspectives of energy consumption reduction and renewable energy harvesting. Specifically, it explains how traffic steering can improve energy efficiency through intelligent traffic-resource matching. Several promising traffic steering approaches for dynamic network planning and renewable energy demand-supply balancing are discussed. This book presents an energy-aware traffic steering method for networks with energy harvesting, which optimizes the traffic allocated to each cell based on the renewable energy status. Renewable energy demand-supply balancing is a key factor in energy dynamics, aimed at enhancing renewable energy sustainability to reduce on-grid energy consum...

  19. Percutaneous Antegrade Varicocele Embolization Via the Testicular Vein in a Patient with Recurrent Varicocele After Surgical Repair

    Energy Technology Data Exchange (ETDEWEB)

    Guevara, Carlos J., E-mail: guevarac@mir.wustl.edu; El-Hilal, Alexander H., E-mail: elhilala@mir.wustl.edu; Darcy, Michael D., E-mail: darcym@mir.wustl.edu [Washington University in St. Louis, Department of Radiology, School of Medicine (United States)

    2015-10-15

    This is a case report of an adolescent male who underwent surgical ligation for a left-sided varicocele that recurred 2 years later. Standard retrograde embolization via the left renal vein was not possible, because there was no connection from the renal vein to the gonadal vein following surgical ligation. The patient was treated via antegrade access of the spermatic vein at the inguinal level with subsequent coil embolization.

  20. Percutaneous Antegrade Varicocele Embolization Via the Testicular Vein in a Patient with Recurrent Varicocele After Surgical Repair.

    Science.gov (United States)

    Guevara, Carlos J; El-Hilal, Alexander H; Darcy, Michael D

    2015-10-01

    This is a case report of an adolescent male who underwent surgical ligation for a left-sided varicocele that recurred 2 years later. Standard retrograde embolization via the left renal vein was not possible, because there was no connection from the renal vein to the gonadal vein following surgical ligation. The patient was treated via antegrade access of the spermatic vein at the inguinal level with subsequent coil embolization.

  1. Complex fractures of the humeral shaft treated with antegrade locked intramedullary nail: clinical experience and long-term results.

    Science.gov (United States)

    Campochiaro, Gabriele; Baudi, Paolo; Loschi, Roberta; Serafin, F; Catani, Fabio

    2015-04-27

    indications for surgical treatment of complex humeral shaft fractures are still controversial. The purpose of this study was to evaluate the outcomes of treating humeral shaft fractures using antegrade locked  intramedullary nail, compared to the treatment with traditional more aggressive techniques such as plate and screws. between February 2008 and January 2011 38 patients were treated with antegrade locked intramedullary nail for humeral shaft fractures, divided according to the AO classification. 28 patients were clinically followed: disability, pain and functional recovery were evaluated using the Constant score and DASH score and the ROM of the shoulder was checked. Bony union was obtained in 27 patients at a mean time of 2.7 months. One fracture ended in nonunion, healed after replacing the nail with a longer one. Patients achieved satisfactory shoulder function with a mean Constant score of  90.57 points and with a mean DASH score of 4.69 points. There were no other complications. the antegrade locked intramedullary nail represents a recommended option for the treatment of humeral shaft fractures, obtaining a steady synthesis, a short time of consolidation and a rapid functional recovery. (www.actabiomedica.it).

  2. The Use of ExoSeal Vascular Closure Device for Direct Antegrade Superficial Femoral Artery Puncture Site Hemostasis

    Energy Technology Data Exchange (ETDEWEB)

    Rimon, Uri, E-mail: rimonu@sheba.health.gov.il; Khaitovich, Boris, E-mail: borislena@012.net.il [Tel-Aviv University, Diagnostic and Interventional Imaging Department, Chaim Sheba Medical Center, Tel-Hashomer, Affiliated to the Sackler School of Medicine (Israel); Yakubovich, Dmitry, E-mail: Dmitry.Yakubovitch@sheba.health.gov.il [Tel-Aviv University, Vascular Surgery Department, Chaim Sheba Medical Center, Tel-Hashomer, Affiliated to the Sackler School of Medicine (Israel); Bensaid, Paul, E-mail: paulbensaid@hotmail.com; Golan, Gil, E-mail: gilgolan201@gmail.com [Tel-Aviv University, Diagnostic and Interventional Imaging Department, Chaim Sheba Medical Center, Tel-Hashomer, Affiliated to the Sackler School of Medicine (Israel); Silverberg, Daniel, E-mail: Daniel.Silverberg@sheba.health.gov.il [Tel-Aviv University, Vascular Surgery Department, Chaim Sheba Medical Center, Tel-Hashomer, Affiliated to the Sackler School of Medicine (Israel)

    2015-06-15

    PurposeThis study was designed to assess the efficacy and safety of the ExoSeal vascular closure device (VCD) to achieve hemostasis in antegrade access of the superficial femoral artery (SFA).MethodsWe retrospectively reviewed the outcome of ExoSeal VCD used for hemostasis in 110 accesses to the SFA in 93 patients between July 2011 and July 2013. All patients had patent proximal SFA based on computer tomography angiography or ultrasound duplex. Arterial calcifications at puncture site were graded using fluoroscopy. The SFA was accessed in an antegrade fashion with ultrasound or fluoroscopic guidance. In all patients, 5–7F vascular sheaths were used. The ExoSeal VCD was applied to achieve hemostasis at the end of the procedure. All patients were clinically examined and had ultrasound duplex exam for any puncture site complications during the 24 h postprocedure.ResultsIn all procedures, the ExoSeal was applied successfully. We did not encounter any device-related technical failure. There were four major complications in four patients (3.6 %): three pseudoaneurysms, which were treated with direct thrombin injection, and one hematoma, which necessitated transfusion of two blood units. All patients with complications were treated with anticoagulation preprocedure or received thrombolytic therapy.ConclusionsThe ExoSeal VCD can be safely used for antegrade puncture of the SFA, with a high procedural success rate (100 %) and a low rate of access site complications (3.6 %)

  3. Endoscopic ultrasound-guided hepaticogastrostomy and antegrade clearance of biliary lithiasis in patients with surgically-altered anatomy.

    Science.gov (United States)

    Hosmer, Amy; Abdelfatah, Mohamed M; Law, Ryan; Baron, Todd H

    2018-02-01

     Endoscopic retrograde cholangiography (ERC) in patients with complex surgically-altered anatomy (SAA) is technically demanding and has limitations. Developments in EUS-guided procedures allow alternative approaches for patients with altered gastrointestinal anatomy and biliary lithiasis.  Single-center, retrospective review of prospectively entered patients with SAA who underwent EUS-guided hepaticogastrostomy (HGS) followed by an interval antegrade endoscopic clearance of biliary lithiasis.  9 patients with Roux-en-Y anatomy underwent HGS to allow clearance of biliary lithiasis after a mean of 2.5 procedures. Technical success was achieved in 100 % of patients utilizing subsequent antegrade endoscopic techniques after HGS including: balloon sweep (9), transpapillary balloon dilation (8), cholangioscopy with electrohydraulic lithotripsy (4), and mechanical lithotripsy (1). HGS stents were removed in all patients. 1 adverse event (cholangitis) occurred after cholangioscopy and prolonged intraductal electrohydraulic lithotripsy.  EUS-guided antegrade therapy for the management of biliary lithiasis in patients with altered gastrointestinal anatomy appears efficacious with a low risk of adverse events. These preliminary results suggest this approach should be considered at centers with available expertise.

  4. A comparison of a 'J' wire and a straight wire in successful antegrade cannulation of the superficial femoral artery

    International Nuclear Information System (INIS)

    Gay, D.A.T.; Edwards, A.J.; Puckett, M.A.; Roobottom, C.A.

    2005-01-01

    AIMS: To evaluate the success of two different types of wire in common use in their ability to successfully cannulate the superficial femoral artery (SFA) using antegrade puncture. METHODS: 50 consecutive patients in whom antegrade infra-inguinal intervention was planned, underwent common femoral arterial puncture and then cannulation with either a standard 3 mm 'J' wire or a floppy tipped straight wire (William Cook--Europe). The frequency with which each type of wire entered the SFA or profunda femoris artery without image guidance was recorded. Further analysis was also made of the success of manipulation of the wire into the SFA following profunda cannulation and the use of alternative guide wires. RESULTS: In 19 out of 25 (76%) patients the 'J' wire correctly entered the SFA without image guidance. Only 5 out of 25 (25%) of straight wires entered the SFA with the initial pass (p<0.0001). Following further manipulation with the same wire all except 1 'J' wire was successfully negotiated into the SFA. The same was true for only 9 of the remaining straight wires with 11 patients requiring an alternative guide wire. CONCLUSIONS: When performing antegrade cannulation of the SFA a 'J' wire is more likely to be successful than a straight guide wire

  5. Risk of injury to the axillary nerve during antegrade proximal humeral blade nail fixation - an anatomical study.

    Science.gov (United States)

    Spiegelberg, Ben G I; Riley, Nicholas D; Taylor, Geoffrey J

    2014-08-01

    The antegrade intramedullary Locking Blade Nail (Marquardt, Germany) is a device aimed at improving purchase in the humeral head and reducing varus displacement by providing medial buttress support and triangular stability within the humeral head. The aim of this study is to measure the relationship of the proximal fixation screws to the axillary nerve. 13 whole cadavers underwent insertion of an antegrade proximal humeral blade nail via a deltoid split approach to both shoulders. The anatomic proximity of the anterior branch of the axillary nerve to the screws was measured following soft tissue dissection and inspection of the nerve. The mean distance of the nerve from the anterolateral acromion was 62 mm (range 45-81 mm). The nerve lay closest to the distal blade fixation screw 4.9 mm (range 0-19 mm). In three cases the nerve lay directly underneath the washer and in all three cases there was macroscopic evidence of damage to the nerve. In 5 cases the nerve travelled obliquely in a cranial direction to lie 1.8 mm (range 0-3 mm) from the distal blade fixation screw, in 2 of these cases the nerve lay beneath the washer. The anterior branch of the axillary nerve is placed at risk during insertion of the locking screws despite use of protection sleeves and trocars. We advocate that when using antegrade intramedullary nails that incorporate an inferomedial calcar screw an extended anterolateral acromial approach is undertaken. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Beam Steering Devices Reduce Payload Weight

    Science.gov (United States)

    2012-01-01

    Scientists have long been able to shift the direction of a laser beam, steering it toward a target, but often the strength and focus of the light is altered. For precision applications, where the quality of the beam cannot be compromised, scientists have typically turned to mechanical steering methods, redirecting the source of the beam by swinging the entire laser apparatus toward the target. Just as the mechanical methods used for turning cars has evolved into simpler, lighter, power steering methods, so has the means by which researchers can direct lasers. Some of the typical contraptions used to redirect lasers are large and bulky, relying on steering gimbals pivoted, rotating supports to shift the device toward its intended target. These devices, some as large and awkward as a piece of heavy luggage, are subject to the same issues confronted by mechanical parts: Components rub, wear out, and get stuck. The poor reliability and bulk not to mention the power requirements to run one of the machines have made mechanical beam steering components less than ideal for use in applications where weight, bulk, and maneuverability are prime concerns, such as on an unmanned aerial vehicle (UAV) or a microscope. The solution to developing reliable, lighter weight, nonmechanical steering methods to replace the hefty steering boxes was to think outside the box, and a NASA research partner did just that by developing a new beam steering method that bends and redirects the beam, as opposed to shifting the entire apparatus. The benefits include lower power requirements, a smaller footprint, reduced weight, and better control and flexibility in steering capabilities. Such benefits are realized without sacrificing aperture size, efficiency, or scanning range, and can be applied to myriad uses: propulsion systems, structures, radiation protection systems, and landing systems.

  7. Steer-by-wire steering system with enhanced functionality for rear steered vehicles

    Directory of Open Access Journals (Sweden)

    Christoph Dillmann

    2015-12-01

    Full Text Available Heckgelenkte selbstfahrende Erntemaschinen sind die zentralen Elemente moderner Ernteketten in der Landwirtschaft. Das primär auf Bodenschonung ausgelegte Fahrwerk, die aktuelle Höchstgeschwindigkeit von 40 km/h sowie die systembedingten, fahrdynamischen Nachteile einer heckgelenkten Maschine erschweren jedoch die Fahrzeugführung auf der Straße. Das Spurhalten und Stabilisieren erfordert daher viel Erfahrung und eine hohe Konzentration des Fahrers. Fahrdynamiksysteme können den Fahrzeugführer entlasten und somit das Fahren mit hohen Geschwindigkeiten sicherer und komfortabler gestalten. Im hier vorgestellten Projekt wird in diesem Kontext eine Steer-by-wire-Lenkung mit parametrierbarer Lenkcharakteristik vorgestellt, die auf die unterschiedlichen Vorzüge des Fahrers einstellbar ist und fahrzustandsabhängige Informationen über das Lenkrad an den Bediener übermittelt.

  8. Omni rotational driving and steering wheel

    DEFF Research Database (Denmark)

    2008-01-01

    and steering wheel part (108), where the omni rotational part (106) is provided for infinite rotation relative to the flange part (104) by both a drive motor (110) and a steering motor (114) being positionable on the flange part (104), and the driving and steering wheel part (108) is suspended from the upper...... omni rotational part (105) with a suspension (116) such that wheel part (108) can move relatively to the upper omni rotational part (105) in a suspension direction (118), and a reduction gear (120) for gearing the drive torque is provided in the wheel part (108) in order e.g. to assure traction...

  9. Automated beam steering using optimal control

    Energy Technology Data Exchange (ETDEWEB)

    Allen, C. K. (Christopher K.)

    2004-01-01

    We present a steering algorithm which, with the aid of a model, allows the user to specify beam behavior throughout a beamline, rather than just at specified beam position monitor (BPM) locations. The model is used primarily to compute the values of the beam phase vectors from BPM measurements, and to define cost functions that describe the steering objectives. The steering problem is formulated as constrained optimization problem; however, by applying optimal control theory we can reduce it to an unconstrained optimization whose dimension is the number of control signals.

  10. Meta-analysis of antegrade continence enema in adults with faecal incontinence and constipation.

    Science.gov (United States)

    Chan, D S Y; Delicata, R J

    2016-03-01

    Faecal incontinence and constipation affects up to 20 per cent of the general population, and can be a significant source of distress. The antegrade continence enema (ACE) procedure has been shown to be an effective alternative treatment option for children, but its use in adults requires clarification. A systematic review and meta-analysis was performed to determine outcomes of the ACE procedure in adults with faecal incontinence and constipation. PubMed, MEDLINE and the Cochrane Library (from January 1990 to January 2015) were searched for studies that reported outcomes of ACE in adults with faecal incontinence and constipation. The primary outcome measure was successful use of ACE in the management of symptoms, as determined by continued use at follow-up. Seventeen observational studies involving 426 patients (265 female patients; median age 42 (range 17-84) years) with faecal incontinence (165 patients), constipation (209) or both (52), who had undergone the ACE procedure, were analysed. At a median follow-up of 39 months, the pooled success rate was 74·3 (95 per cent c.i. 66·1 to 82·6) per cent (P constipation (both P constipation, and should be considered before performing a definitive colostomy. Patients with faecal incontinence appear to respond better than those with constipation. © 2016 BJS Society Ltd Published by John Wiley & Sons Ltd.

  11. Antegrade-retrograde opposing lag screws for internal fixation of simple displaced talar neck fractures.

    Science.gov (United States)

    Abdelkafy, Ashraf; Imam, Mohamed Abdelnabi; Sokkar, Sherif; Hirschmann, Michael

    2015-01-01

    The talar neck is deviated medially with reference to the long axis of the body of the talus. In addition, it deviates plantarward. The talar neck fracture line is sometimes observed to be oriented obliquely (not perpendicular to the long axis of the talar neck). This occurs when the medially deviated talar neck strikes the horizontally oriented anterior lower tibial edge. Internal fixation of a simple displaced talar neck fracture usually requires 2 lag screws. Because the fracture line is obliquely oriented, a better method for positioning the screws perpendicular to the fracture line is to place them in a reversed direction to provide maximum interfragmentary compression at the fracture site, which could increase the likelihood of absolute stability with subsequent improvement in the incidence of fracture union and a reduction of complications, such as avascular necrosis of the body of the talus. Two lag screws are used, with the first inserted from posteriorly to anteriorly (perpendicular to the fracture line) using a medial approach after medial malleolar chevron osteotomy. The second screw is inserted from anteriorly to posteriorly (perpendicular to the fracture line) using an anterolateral approach. Both screw heads should be countersunk. A series of 8 patients underwent this form of internal fixation for talar neck fracture repair, with satisfactory functional outcomes. In conclusion, the use of antegrade-retrograde opposing lag screws is a reasonable method of internal fixation for simple displaced talar neck fractures. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Frequency Steered Acoustic Transducer, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase II project is to fabricate, characterize, and verify performance of a new type of frequency steered acoustic transducer...

  13. Frequency Steered Acoustic Transducer, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project is to develop, fabricate, and characterize a novel frequency steered acoustic transducer (FSAT) for the...

  14. CCCT - NCTN Steering Committees - Gynecologic Cancers

    Science.gov (United States)

    The Gynecologic Cancers Steering Committee evaluates and prioritizes concepts for phase 2 and 3 clinical trials in adult gynecologic cancers. The GCSC is also intent on fostering collaboration with international groups and institutions conducting trials.

  15. Antegrade scrotal sclerotherapy of internal spermatic veins for varicocele treatment: technique, complications, and results

    Directory of Open Access Journals (Sweden)

    Alessandro Crestani

    2016-01-01

    Full Text Available Varicocele repair is mainly indicated in young adult patients with clinical palpable varicocele and abnormal semen parameters. Varicocele treatment is associated with a significant improvement in sperm concentration, motility, morphology, and pregnancy rate. Antegrade scrotal sclerotherapy (ASS represented one of the main alternatives to the traditional inguinal or suprainguinal surgical ligation. This article reviews the use of ASS for varicocele treatment. We provide a brief overview of the history of the procedure and present our methods used in ASS. In addition, we review complication and success of ASS, including our own retrospective data of treating 674 patients over the last 17 years. Herein, we analyzed step by step the ASS technique and described our results with an original modified technique with a long follow-up. Between December 1997 and December 2014, we performed 674 ASS. Mean operative time was 14 min (range 9 to 50 min. No significant intraoperative complications were reported. Within 90 days from the procedure, postoperative complications were recorded in overall 49 (7.2% patients. No major complications were recorded. A persistent/recurrent varicocele was detected in 40 (5.9% cases. In 32/40 (80% cases, patients showed preoperative grade III varicoceles. In patients with a low sperm number before surgery, sperm count improved from 13 × 10 6 to 21 × 10 6 ml−1 (P < 0.001. The median value of the percentage of progressive motile forms at 1 h improved from 25% to 45% (P < 0.001. Percentage of normal forms increased from 17% before surgery to 35% 1 year after the procedure (P < 0.001. In the subgroup of the 168 infertile patients, 52 (31% fathered offspring at a 12-month-minimum follow-up. Therefore, ASS is an effective minimal invasive treatment for varicocele with low recurrence/persistence rate.

  16. The effects of simultaneous antegrade/retrograde cardioplegia on cellular volumes and energy metabolism.

    Science.gov (United States)

    Li, Gang; Tian, Weichen; Wang, Jian; Xiang, Bo; Wang, Lei; Deng, Jixian; Salerno, Tomas A; Deslauriers, Roxanne; Tian, Ganghong

    2008-01-01

    Simultaneous antegrade/retrograde cardioplegia (SARC) has been employed frequently during cardiac surgery to preserve the jeopardized myocardium. However, retrograde perfusion of SARC may interfere with myocardial drainage and disrupt myocardial fluid homeostasis, which may affect the myocardial energy metabolism and contractile function. The study was, therefore, designed to assess the effects of SARC on myocardial fluid homeostasis, cellular volumes, and energy metabolism. Eight isolated pig hearts were subjected to a protocol consisting of a 20-minute control perfusion, 120-minute SARC, and 20-minute reperfusion. The myocardial water content was monitored using near-infrared spectroscopy. Phosphorus-31 magnetic resonance ((31)P MR) spectroscopy was used to monitor the volumes of both intracellular and extracellular compartments and assess myocardial energy metabolism. The near-infrared spectra showed that the 120-min SARC resulted in a 60 +/- 12% increase in the myocardial water content. (31)P MR spectra showed a 36 +/- 4% increase in the intracellular compartment and a 54 +/- 8% increase in the extracellular compartment during SARC relative to their initial volumes measured during control perfusion (100%). However, the myocardial energy metabolites (adenosine triphosphate [ATP] and phosphocreatine [PCr]) remained unchanged during the 120-minute SARC. Moreover, during reperfusion, the hearts showed an almost complete recovery in the left ventricular-developed pressure. A prolonged SARC resulted in water accumulation in both extracellular and intracellular compartments in the normal myocardium. Although its detrimental effect on tissue fluid homeostasis did not jeopardize the myocardial energy metabolism, a prolonged use of SARC should be avoided, particularly in the diseased hearts.

  17. Obesity: An Independent Risk Factor for Insufficient Hemostasis Using the AngioSeal Vascular Closure Device After Antegrade Puncture

    International Nuclear Information System (INIS)

    Minko, Peter; Katoh, Marcus; Gräber, Stefan; Buecker, Arno

    2012-01-01

    Purpose: This study was designed to investigate the efficacy of the AngioSeal vascular closure device after antegrade puncture of the femoral artery. Methods: In a prospective study, 120 consecutive patients underwent lower limb vascular intervention by an antegrade access to the common femoral artery (CFA). After intervention, a 6F (n = 88) or an 8F (n = 32) AngioSeal vascular closure device was used to achieve hemostasis. The technical success or the cause of failure was documented. In addition, the coagulation status (platelets, INR, prothrombin time, atrial thromboplastin time (PTT)), hypertonus, locoregional habitus of the groin, body mass index (BMI), presence of calcifications, and history of previous surgical interventions of the CFA were evaluated. Results: Hemostasis was achieved in 97 patients (81%). In 12 patients (10%), persistent bleeding of the puncture site required manual compression. In another nine patients (8%) a kink of the sheath obviated the passage of the collagen plug toward the vessel, and in two patients the anchor dislodged out of the vessel, requiring manual compression. There were no significant differences between the groups of successful and unsuccessful sealing regarding the mean platelets (241 vs. 254 * 10 9 /l; P = 0.86), INR (1.06 vs. 1.02; P = 0.52), prothrombin time (90% vs. 90%; P = 0.86), and PTT (30 vs. 31 s; P = 0.82). However, unsuccessful sealing was more likely in obese patients with an increased BMI (26.6 vs. 28.8 kg/m 2 ; P = 0.04). Conclusions: Obesity seems to be an independent risk factor for insufficient sealing using the AngioSeal vascular closure device after antegrade puncture of the CFA. In 8% of our patients, hemostasis could not be achieved due to kink of the flexible sheath.

  18. Biomechanical evaluation of straight antegrade nailing in proximal humeral fractures: the rationale of the "proximal anchoring point".

    Science.gov (United States)

    Euler, Simon A; Petri, Maximilian; Venderley, Melanie B; Dornan, Grant J; Schmoelz, Werner; Turnbull, Travis Lee; Plecko, Michael; Kralinger, Franz S; Millett, Peter J

    2017-09-01

    Varus failure is one of the most common failure modes following surgical treatment of proximal humeral fractures. Straight antegrade nails (SAN) theoretically provide increased stability by anchoring to the densest zone of the proximal humerus (subchondral zone) with the end of the nail. The aim of this study was to biomechanically investigate the characteristics of this "proximal anchoring point" (PAP). We hypothesized that the PAP would improve stability compared to the same construct without the PAP. Straight antegrade humeral nailing was performed in 20 matched pairs of human cadaveric humeri for a simulated unstable two-part fracture. Biomechanical testing, with stepwise increasing cyclic axial loading (50-N increments each 100 cycles) at an angle of 20° abduction revealed significantly higher median loads to failure for SAN constructs with the PAP (median, 450 N; range, 200-1.000 N) compared to those without the PAP (median, 325 N; range, 100-500 N; p = 0.009). SAN constructs with press-fit proximal extensions (endcaps) showed similar median loads to failure (median, 400 N; range, 200-650 N), when compared to the undersized, commercially available SAN endcaps (median, 450 N; range, 200-600 N; p = 0.240). The PAP provided significantly increased stability in SAN constructs compared to the same setup without this additional proximal anchoring point. Varus-displacing forces to the humeral head were superiorly reduced in this setting. This study provides biomechanical evidence for the "proximal anchoring point's" rationale. Straight antegrade humeral nailing may be beneficial for patients undergoing surgical treatment for unstable proximal humeral fractures to decrease secondary varus displacement and thus potentially reduce revision rates.

  19. Antegrade versus retrograde cerebral perfusion in relation to postoperative complications following aortic arch surgery for acute aortic dissection type A.

    Science.gov (United States)

    Apostolakis, Efstratios; Koletsis, Efstratios N; Dedeilias, Panagiotis; Kokotsakis, John N; Sakellaropoulos, George; Psevdi, Argini; Bolos, Konstantin; Dougenis, Dimitrios

    2008-01-01

    Aortic arch surgery is impossible without the temporary interruption of brain perfusion and therefore is associated with high incidence of neurologic injury. The deep hypothermic circulatory arrest (HCA), in combination with antegrade or retrograde cerebral perfusion (RCP), is a well-established method of brain protection in aortic arch surgery. In this retrospective study, we compare the two methods of brain perfusion. From 1998 to 2006, 48 consecutive patients were urgently operated for acute type A aortic dissection and underwent arch replacement under deep hypothermic circulatory arrest (DHCA). All distal anastomoses were performed with open aorta, and the arch was replaced totally in 15 cases and partially in the remaining 33 cases. Our patient cohort is divided into those protected with antegrade cerebral perfusion (ACP) (group A, n = 23) and those protected with RCP (group B, n = 25). No significant difference was found between groups A and B with respect to cardiopulmonary bypass-time, brain-ischemia time, cerebral-perfusion time, permanent neurologic dysfunction, and mortality. The incidence of temporary neurologic dysfunction was 16.0% for group A and 43.50% for group B (p = 0.04). The mean extubation time was 3.39 +/- 1.40 days for group A and 4.96 +/- 1.83 days for group B (p = 0.0018). The mean ICU-stay was 4.4 +/- 2.3 days for group A and 6.9 +/- 2.84 days for group B (p = 0.0017). The hospital-stay was 14.38 +/- 4.06 days for group A and 19.65 +/- 6.91 days for group B (p = 0.0026). The antegrade perfusion seems to be related with significantly lower incidence of temporary neurological complications, earlier extubation, shorter ICU-stay, and hospitalization, and hence lower total cost.

  20. Combined antegrade femoral artery and retrograde popliteal artery recanalization for chronic occlusions of the superficial femoral artery.

    Science.gov (United States)

    Shi, Weihao; Yao, Ye; Wang, Wei; Yu, Bo; Wang, Song; Que, Huafa; Xiang, Huanyu; Li, Qiong; Zhao, Qiufeng; Zhang, Zhen; Xu, Jienan; Liu, Xiaodong; Shen, Liang; Xing, Jie; Wang, Yunfei; Shan, Wei; Zhou, Jie

    2014-09-01

    To evaluate the efficacy and safety of a dual femoral-popliteal approach in the supine position after failed antegrade recanalization attempts in chronic total occlusion (CTO) of the superficial femoral artery (SFA). From May 2011 to October 2012, 21 patients underwent dual femoral-popliteal recanalization for CTO of the SFA, with a mean lesion length of 87.4 mm ± 5.8. When contralateral antegrade recanalization of SFA occlusions via the common femoral artery could not be achieved, the occlusions were intrainterventionally accessed by retrograde approach via the popliteal artery, which was punctured anteriorly with gently flexed knee and crus extorsion. When the SFA had been recanalized, further angioplasty and stent placement procedures were completed via the femoral artery. A technical success rate of 100% (entailing puncture of the popliteal artery and SFA recanalization) was achieved, and no hemorrhage, hematoma, pseudoaneurysm, arteriovenous fistula, or other complications developed. During a mean follow-up of 9.8 months ± 1.5, claudication severity, rest pain, and toe ulcers improved significantly. The pulse of the distal arteries, as well as the filling of the veins, could be distinctly felt. Ankle-brachial index changed from 0.48 ± 0.17 to 0.84 ± 0.11 at 1 year after intervention (P < .001), and patency rates at 1, 6, and 12 months after interventions were 100%, 80%, and 42%, respectively. A dual femoral-popliteal approach in the supine position is an alternative backup option after failed attempts at the antegrade approach for patients with proximal barriers in CTO or lesions with major extending collateral vessels. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  1. Routine Use of Surgical Retrograde Transtibial Endovascular Approach for Failed Attempts at Antegrade Recanalization of Chronic Peripheral Artery Total Occlusions

    International Nuclear Information System (INIS)

    Liang, GangZhu; Zhang, FuXian; Luo, XiaoYun; Zhang, ChangMing; Feng, YaPing; Niu, LuYuan; Zhang, Huan; Hu, Lu; Zhao, Hui; Cheng, Long; Zhang, MingYi

    2016-01-01

    PurposeOur aim was to describe the technical aspects and clinical outcomes of an open surgical approach to retrograde transtibial endovascular therapy for recanalization of chronic total occlusions (CTOs) of peripheral arteries because of inability to acquire antegrade intravascular access across the occlusion.Materials and MethodsBetween January 2011 and May 2014, conventional antegrade revascularization failed in 15 limbs of 15 patients (11 males, 4 females) with complex CTOs. The mean age of the patients was 74 years (range 48–83 years). Five patients had severe claudication (Rutherford Category 3), and 10 patients had critical limb-threatening ischemia (Rutherford Categories 4–5). For each of these cases of antegrade failure, an open surgical exposure of the tibial or dorsalis pedis artery was used to allow a safe retrograde transtibial endovascular approach to recanalize the CTO.ResultsSurgical retrograde access from the tibial artery was achieved successfully in 14 of the 15 patients. In the 14 successful retrograde endovascular approaches, surgical retrograde transtibial access was achieved from the dorsalis pedis artery in 8 patients and from the posterior tibial artery in 6. The average time to obtain retrograde access was 5 min (range 2–11 min). No stenosis or occlusion occurred in the tibial or dorsalis pedis arteries used for the retrograde access sites during follow-up.ConclusionsRoutine surgical exposure can be a safe and an effective method for retrograde transtibial access to the more proximal occluded arterial segments in selected patients with CTO.

  2. Routine Use of Surgical Retrograde Transtibial Endovascular Approach for Failed Attempts at Antegrade Recanalization of Chronic Peripheral Artery Total Occlusions

    Energy Technology Data Exchange (ETDEWEB)

    Liang, GangZhu; Zhang, FuXian, E-mail: gangzhuliang@126.com; Luo, XiaoYun; Zhang, ChangMing; Feng, YaPing; Niu, LuYuan; Zhang, Huan; Hu, Lu; Zhao, Hui; Cheng, Long; Zhang, MingYi [Capital Medical University, Department of Vascular Surgery, Beijing Shijitan Hospital (China)

    2016-12-15

    PurposeOur aim was to describe the technical aspects and clinical outcomes of an open surgical approach to retrograde transtibial endovascular therapy for recanalization of chronic total occlusions (CTOs) of peripheral arteries because of inability to acquire antegrade intravascular access across the occlusion.Materials and MethodsBetween January 2011 and May 2014, conventional antegrade revascularization failed in 15 limbs of 15 patients (11 males, 4 females) with complex CTOs. The mean age of the patients was 74 years (range 48–83 years). Five patients had severe claudication (Rutherford Category 3), and 10 patients had critical limb-threatening ischemia (Rutherford Categories 4–5). For each of these cases of antegrade failure, an open surgical exposure of the tibial or dorsalis pedis artery was used to allow a safe retrograde transtibial endovascular approach to recanalize the CTO.ResultsSurgical retrograde access from the tibial artery was achieved successfully in 14 of the 15 patients. In the 14 successful retrograde endovascular approaches, surgical retrograde transtibial access was achieved from the dorsalis pedis artery in 8 patients and from the posterior tibial artery in 6. The average time to obtain retrograde access was 5 min (range 2–11 min). No stenosis or occlusion occurred in the tibial or dorsalis pedis arteries used for the retrograde access sites during follow-up.ConclusionsRoutine surgical exposure can be a safe and an effective method for retrograde transtibial access to the more proximal occluded arterial segments in selected patients with CTO.

  3. Obesity: An Independent Risk Factor for Insufficient Hemostasis Using the AngioSeal Vascular Closure Device After Antegrade Puncture

    Energy Technology Data Exchange (ETDEWEB)

    Minko, Peter, E-mail: peterminko@yahoo.com; Katoh, Marcus [University Hospital Saarland, Department of Diagnostic and Interventional Radiology (Germany); Graeber, Stefan [University Hospital Saarland, Institute of Medical Biometry, Epidemiology and Medical Informatics (Germany); Buecker, Arno [University Hospital Saarland, Department of Diagnostic and Interventional Radiology (Germany)

    2012-08-15

    Purpose: This study was designed to investigate the efficacy of the AngioSeal vascular closure device after antegrade puncture of the femoral artery. Methods: In a prospective study, 120 consecutive patients underwent lower limb vascular intervention by an antegrade access to the common femoral artery (CFA). After intervention, a 6F (n = 88) or an 8F (n = 32) AngioSeal vascular closure device was used to achieve hemostasis. The technical success or the cause of failure was documented. In addition, the coagulation status (platelets, INR, prothrombin time, atrial thromboplastin time (PTT)), hypertonus, locoregional habitus of the groin, body mass index (BMI), presence of calcifications, and history of previous surgical interventions of the CFA were evaluated. Results: Hemostasis was achieved in 97 patients (81%). In 12 patients (10%), persistent bleeding of the puncture site required manual compression. In another nine patients (8%) a kink of the sheath obviated the passage of the collagen plug toward the vessel, and in two patients the anchor dislodged out of the vessel, requiring manual compression. There were no significant differences between the groups of successful and unsuccessful sealing regarding the mean platelets (241 vs. 254 * 10{sup 9}/l; P = 0.86), INR (1.06 vs. 1.02; P = 0.52), prothrombin time (90% vs. 90%; P = 0.86), and PTT (30 vs. 31 s; P = 0.82). However, unsuccessful sealing was more likely in obese patients with an increased BMI (26.6 vs. 28.8 kg/m{sup 2}; P = 0.04). Conclusions: Obesity seems to be an independent risk factor for insufficient sealing using the AngioSeal vascular closure device after antegrade puncture of the CFA. In 8% of our patients, hemostasis could not be achieved due to kink of the flexible sheath.

  4. Stability analysis of automobile driver steering control

    Science.gov (United States)

    Allen, R. W.

    1981-01-01

    In steering an automobile, the driver must basically control the direction of the car's trajectory (heading angle) and the lateral deviation of the car relative to a delineated pathway. A previously published linear control model of driver steering behavior which is analyzed from a stability point of view is considered. A simple approximate expression for a stability parameter, phase margin, is derived in terms of various driver and vehicle control parameters, and boundaries for stability are discussed. A field test study is reviewed that includes the measurement of driver steering control parameters. Phase margins derived for a range of vehicle characteristics are found to be generally consistent with known adaptive properties of the human operator. The implications of these results are discussed in terms of driver adaptive behavior.

  5. Steering object-oriented computations with Python

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T.-Y.B.; Dubois, P.F.; Furnish, G. [Lawrence Livermore National Lab., CA (United States); Beazley, D.M. [Utah Univ., Salt Lake City, UT (United States). Dept. of Computer Science

    1996-10-01

    We have described current approaches and future plans for steering C++ application, running Python on parallel platforms, and combination of Tk interface and Python interpreter in steering computations. In addition, there has been significant enhancement in the Gist module. Tk mega widgets has been implemented for a few physics applications. We have also written Python interface to SIJLO, a data storage package used as an interface to a visualization system named MeshTv. Python is being used to control large-scale simulations (molecular dynamics in particular) running on the CM-5 and T3D at LANL as well. A few other code development projects at LLNL are either using or considering Python as their steering shells. In summary, the merits of Python have been appreciated by more and more people in the scientific computation community.

  6. Transverse steering of two-component beams

    International Nuclear Information System (INIS)

    Murin, B.P.; Bondarev, B.U.; Durkin, A.P.; Lomize, L.G.; Soloviev, L.Yu.; Fedotov, A.P.

    Coherent transverse oscillations are considered which occur during simultaneous acceleration of proton and H - beams due to arbitrary displacements in elements of the focusing channel. To suppress these oscillations, a beam adjustment station is proposed, in which each quadrupole lens of two doublets is provided with a special dipole component of the magnetic field. These steering elements, together with the beam transverse position monitors, permit steering the transverse position of beams of opposite signs in both transverse planes. The number of steering stations needed is chosen, and some algorithms for control are discussed. It is shown that some of the control algorithms will permit not only the suppression of coherent oscillations, but a decrease in the radius and emittance of the beam

  7. Role of thermal noise in tripartite quantum steering

    Science.gov (United States)

    Wang, Meng; Gong, Qihuang; Ficek, Zbigniew; He, Qiongyi

    2014-08-01

    The influence of thermal noise on bipartite and tripartite quantum steering induced by a short laser pulse in a hybrid three-mode optomechanical system is investigated. The calculation is carried out under the bad cavity limit, the adiabatic approximation of a slowly varying amplitude of the cavity mode, and with the assumption of driving the cavity mode with a blue detuned strong laser pulse. Under such conditions, explicit expressions of the bipartite and tripartite steering parameters are obtained, and the concept of collective tripartite quantum steering, recently introduced by He and Reid [Phys. Rev. Lett. 111, 250403 (2013), 10.1103/PhysRevLett.111.250403], is clearly explored. It is found that both bipartite and tripartite steering parameters are sensitive functions of the initial state of the modes and distinctly different steering behavior could be observed depending on whether the modes were initially in a thermal state or not. For the modes initially in a vacuum state, the bipartite and tripartite steering occur simultaneously over the entire interaction time. This indicates that collective tripartite steering cannot be achieved. The collective steering can be achieved for the modes initially prepared in a thermal state. We find that the initial thermal noise is more effective in destroying the bipartite rather than the tripartite steering which, on the other hand, can persist even for a large thermal noise. For the initial vacuum state of a steered mode, the tripartite steering exists over the entire interaction time even if the steering modes are in very noisy thermal states. When the steered mode is initially in a thermal state, it can be collectively steered by the other modes. There are thresholds for the average number of the thermal photons above which the existing tripartite steering appears as the collective steering. Finally, we point out that the collective steering may provide a resource in a hybrid quantum network for quantum secret sharing

  8. A model of driver steering control incorporating the driver's sensing of steering torque

    Science.gov (United States)

    Kim, Namho; Cole, David J.

    2011-10-01

    Steering feel, or steering torque feedback, is widely regarded as an important aspect of the handling quality of a vehicle. Despite this, there is little theoretical understanding of its role. This paper describes an initial attempt to model the role of steering torque feedback arising from lateral tyre forces. The path-following control of a nonlinear vehicle model is implemented using a time-varying model predictive controller. A series of Kalman filters are used to represent the driver's ability to generate estimates of the system states from noisy sensory measurements, including the steering torque. It is found that under constant road friction conditions, the steering torque feedback reduces path-following errors provided the friction is sufficiently high to prevent frequent saturation of the tyres. When the driver model is extended to allow identification of, and adaptation to, a varying friction condition, it is found that the steering torque assists in the accurate identification of the friction condition. The simulation results give insight into the role of steering torque feedback arising from lateral tyre forces. The paper concludes with recommendations for further work.

  9. Online optimized hysteresis-based steering feel model for steer-by-wire systems

    Directory of Open Access Journals (Sweden)

    Ahmet Kirli

    2016-06-01

    Full Text Available In rubber-wheeled road vehicles, the mechanical connection between steering wheel and front wheels provides steering-related feedback to the driver. The torque fed back to the driver through the steering linkages and steering wheel, which is called steering feel, helps the driver in controlling the vehicle. The torque feedback is reproduced via artificial methods in steer-by-wire systems due to the lack of mechanical connection. In this work, in order to minimize the physical workload and the lateral acceleration under the consideration of handling performance, optimization of a hysteresis-based steering feel has been studied. A 2-degree-of-freedom bicycle model based on the magic formula tire model has been used for simulations and hardware-in-the-loop experiments. A mathematical model is proposed in order to create an adaptive model-based optimization of the hysteresis parameters simultaneously while driving. A hardware-in-the-loop experimental setup has been used for the driving tests. The weave and the double-lane change tests have been performed with different drivers in order to demonstrate and quantify the optimization methods that are presented in this work.

  10. A computer algorithm for automatic beam steering

    International Nuclear Information System (INIS)

    Drennan, E.

    1992-06-01

    Beam steering is done by modifying the current in a trim or bending magnet. If the current change is the right amount the beam can be made to bend in such a manner that it will hit a swic or BPM downstream from the magnet at a predetermined set point. Although both bending magnets and trim magnets can be used to modify beam angle, beam steering is usually done with trim magnets. This is so because, during beam steering the beam angle is usually modified only by a small amount which can be easily achieved with a trim magnet. Thus in this note, all steering magnets will be assumed to be trim magnets. There are two ways of monitoring beam position. One way is done using a BPM and the other is done using a swic. For simplicity, beam position monitoring in this paper will be referred to being done with a swic. Beam steering can be done manually by changing the current through a trim magnet and monitoring the position of the beam downstream from the magnet with a swic. Alternatively the beam can be positioned automatically using a computer which periodically updates the current through a specific number of trim magnets. The purpose of this note is to describe the steps involved in coming up with such a computer program. There are two main aspects to automatic beam steering. First a relationship between the beam position and the bending magnet is needed. Secondly a beamline setup of swics and trim magnets has to be chosen that will position the beam according to the desired specifications. A simple example will be looked at that will show that once a mathematical relationship between the needed change of the beam position on a swic and the change in trim currents is established, a computer could be programmed to calculate and update the trim currents

  11. The relationship of proximal locking screws to the axillary nerve during antegrade humeral nail insertion of four commercially available implants.

    Science.gov (United States)

    Prince, Edward J; Breien, Kristoffer M; Fehringer, Edward V; Mormino, Matthew A

    2004-10-01

    The purpose of this study was to determine the proximity of proximal interlocking mechanisms in 4 current antegrade humeral nails to the axillary nerve and its branches. Cadaveric study. Anatomy laboratory. Anatomic relationships. Four humeral nail designs (labeled SS, SL, SZ, and SN) were each inserted in successive antegrade fashion in 10 cadaveric upper extremity specimens. Three variables were measured: from acromion to the axillary nerve, from acromion to entry sites of proximal locking devices, and from locking devices to axillary nerves and their branches. In nail SS, the proximally directed oblique locking screw came into contact with the ascending branch of the axillary nerve in 6 of 10 specimens. Mean distance from spiral blades in nails SS and SL were 26 mm to the axillary nerve and 16 mm to its ascending branch. Interlocking screws for nails SZ, SN, and SL did not violate the axillary nerve or its branches in any specimen. Mean distance from lateral acromion to the axillary nerve measured 58.7 mm. Nail SS's oblique locking screw may injure the ascending branch of the axillary nerve. Three of the 4 nails tested did not endanger the axillary nerve. However, when transverse proximal locking screws are inserted from a lateral-to-medial direction, they may endanger an arborized axillary nerve. Blunt dissection should be performed with a visible path to bone before instrumentation to reduce the risk of axillary nerve injury. Copyright 2004 Lippincott Williams & Wilkins

  12. Outcome of antegrade continent enema (ACE) procedures in children and young adults.

    Science.gov (United States)

    Masadeh, Maen M; Krein, Michael; Peterson, Joshua; Bauer, Molly; Phearman, Laura; Pitcher, Graeme; Liao, Junlin; Shilyansky, Joel

    2013-10-01

    Intractable incontinence affects a large number of children and young adults in the US. The goal of this study is to evaluate the long-term outcomes of surgical access for administration of antegrade continence enemas (ACE) in affected children and young adults. Patients who underwent surgical procedure to enable administration of ACE from 1994 to 2011 were retrospectively reviewed. Data collected included patient demographics, primary diagnosis, surgical technique, conduit used, complications, follow-up duration, and social continence. Sixty eighty patients underwent surgery to enable ACE; mean follow up was 61 months. Enteral conduit (EC) was performed in 19 patients, tube cecostomy catheters (CC) in 49. Meningomyelocele was diagnosed in 60% of patients. Mean age was 11 (1.67-53) years. Complications included tube dislodgement (43%), granulation tissue (46%), site infection (13%), leakage (32%), break in the tube (6%) and tract stenosis (6%). Complete social continence was achieved in 68%, partial continence was achieved in 29%, and no benefit was achieved in 3% of patients. The rate of complications and incontinence resolution following CC was 78% and 66%, and following EC 89% and 74%. The differences were not statistically significant. CC patients developed granulation tissue more frequently (53%) and leaks of fecal material less frequently (20%) compared to EC patients (26% and 53%) (p < 0.05 and < 0.01). Although children 7 years or younger developed more overall complications (94%) than older patients (69%; p < 0.05), there was not a significant difference in the frequency of any one complication or in the rate of continence, between the two groups. Multivariate analysis showed that EC is three times more likely to be complicated by fecal leakage. CC patients are at greater risk to develop granulation tissue (p < 0.05). Most patients achieved social continence and improved hygiene with the aid of ACE. Younger children also benefited greatly from institution

  13. Drowsy Driver Detection via Steering Wheel

    Directory of Open Access Journals (Sweden)

    Herlina ABDUL RAHIM

    2010-09-01

    Full Text Available The main purpose of this project is to produce a safety system especially for fatigue car driver so as to prevent from accidents. The statistic on road fatality shows that human error constitute of 64.84 % road accidents fatality and 17.4 % due to technical factors. These systems encompassed the approach of hand pressure applied on the steering wheel. The steering will be installed with pressure sensors. At the same time these sensors can be used to measure gripping force while driving.

  14. 46 CFR 182.620 - Auxiliary means of steering.

    Science.gov (United States)

    2010-10-01

    ... TONS) MACHINERY INSTALLATION Steering Systems § 182.620 Auxiliary means of steering. (a) Except as... personnel hazards during normal or heavy weather operation. (b) A suitable hand tiller may be acceptable as...

  15. 9 CFR 78.6 - Steers and spayed heifers.

    Science.gov (United States)

    2010-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.6 Steers and spayed heifers. Steers...

  16. 14 CFR 23.745 - Nose/tail wheel steering.

    Science.gov (United States)

    2010-01-01

    ... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Landing Gear § 23.745 Nose/tail wheel steering. (a) If nose/tail wheel steering is installed, it must be... gear. Floats and Hulls ...

  17. Target ballon-assisted antegrade and retrograde approach for recanalization of thrombosed fem-pop bypass graft using the outbreak catheter

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jung Won; Chung, Hwan Hoon; Lee, Seung Hwa; Yeom, Suk Keu; Cha, Sang Hoon [Dept. of Radiology, Korea University College of Medicine, Ansan Hospital, Ansan (Korea, Republic of)

    2016-01-15

    The subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) technique is reportedly effective in severe peripheral vascular disease that cannot be treated with standard endovascular techniques including subintimal angioplasty. In this report, we used a target balloon with the Outback catheter to recanalize a thrombosed bypass graft that could not be treated successfully with SAFARI.

  18. Static Force-Deflection Properties of Automobile Steering Components

    Science.gov (United States)

    1987-06-01

    This report provides the static force-deflection test results for 28 steering columns and 24 steering wheels used in domestic and import passener cars from model year 1975 to 1985. The steering columns and wheels tested include approzimately 90 perce...

  19. Design and manufacturing of mechanical steering system for ...

    African Journals Online (AJOL)

    Design and manufacturing of mechanical steering system for parallel parking, zero turning radius, minimum turning radius with traditional turning. ... of the steering system are designed so as to meet all the configuration of steering system and to be well-matched to the power train, suspension system and body of the car.

  20. Fault-tolerant Actuator System for Electrical Steering of Vehicles

    DEFF Research Database (Denmark)

    Sørensen, Jesper Sandberg; Blanke, Mogens

    2006-01-01

    Being critical to the safety of vehicles, the steering system is required to maintain the vehicles ability to steer until it is brought to halt, should a fault occur. With electrical steering becoming a cost-effective candidate for electrical powered vehicles, a fault-tolerant architecture...

  1. DSP-based electric power assisted steering using BLDC motor

    Indian Academy of Sciences (India)

    system is experimentally verified and it is tested in one of the Light Commercial. Vehicle (LCV). Keywords. BLDC motor; EAS; steering. 1. Introduction. Power steering is a system for reducing the steering effort on vehicles by using external source to assist in turning the wheels. Most new generation vehicles now have power ...

  2. Steering Dynamics in the Dutch Education System

    Science.gov (United States)

    Waslander, Sietske; Hooge, Edith; Drewes, Tineke

    2016-01-01

    Based on detailed empirical analyses, we paint a layered picture of emerging steering dynamics. Inspired by Foucault, we put the focus on roles stakeholders define both for themselves and others, how they give sense to policy, how they work together in policy elaboration and implementation, and the subtle and sometimes deceitful function of soft…

  3. Biogas production from steer manures in Vietnam

    DEFF Research Database (Denmark)

    Pham, Cuong H.; Saggar, Surinder; Vu, Cuong C.

    2017-01-01

    In developing countries, the simple biogas digesters installed underground without heating or stirring are seen as a 'green' technology to convert animal waste into biogas, a source of bio-energy. However, quantitative estimates of biogas production of manures from steers fed local feed diets...

  4. Offset steering in multiamp ion sources - revisited

    International Nuclear Information System (INIS)

    Ott, W.

    1993-01-01

    Steering of the individual beamlets in multiamp ion beams by offsetting the axes of circular extraction holes in three-electrode acceleration systems is revisited. A consistent application of the Langmuir-Blodgett theory of a spherical diode gives a stronger deflection per unit offset than assumed hitherto. (orig.)

  5. Development of steering system in network environment

    International Nuclear Information System (INIS)

    Kanagawa, Fumihiro; Noguchi, So; Yamashita, Hideo

    2002-01-01

    We have been developing the steering system, which can successively observe the-data obtained during the numerical computation and change the parameters in the analysis. Moreover, this system is also extended to link the network. By using this system, a user can easily detect errors immediately and achieve the rapid and accurate analysis with lower computation cost. (Author)

  6. 49 CFR 570.7 - Steering systems.

    Science.gov (United States)

    2010-10-01

    ... shall not exceed one-quarter of an inch. (1) Inspection procedure. Elevate the front end of the vehicle to load the ball joints. Insure that wheel bearings are correctly adjusted. Grasp the front and rear... a front wheel. If a point on the steering wheel rim moves more than the value shown in Table 1...

  7. Steered wheel for the support and/or steering of a vehicle, particularly hovercraft

    Energy Technology Data Exchange (ETDEWEB)

    Duell, H.J.; Kirchner, G.

    1977-04-07

    The invention concerns a steered wheel for the support or steering of a hovercraft, whose wheel suspension is provided with an eccentric journal for automatic setting in the direction of travel. So that the vehicle will not leave its track during changes of direction when the wheel is turned around the eccentric axis, according to the invention the wheel is supported on movable bearings at the journal in the direction of the driving axle.

  8. The impact of antegrade intramedullary nailing start site using the SIGN nail in proximal femoral fractures: A prospective cohort study.

    Science.gov (United States)

    Mustafa Diab, Mohamed; Wu, Hao-Hua; Eliezer, Edmund; Haonga, Billy; Morshed, Saam; Shearer, David W

    2018-02-01

    In many low and middle-income countries (LMICs) SIGN nail is commonly used for antegrade femoral intramedullary (IM) nailing, using a start site either at the tip of the greater trochanter or piriformis fossa. While a correct start site is considered an essential technical step; few studies have evaluated the impact of using an erroneous start site. This is particularly relevant in settings with limited access to fluoroscopy to aid in creating a nail entry point. The purpose of this study was to evaluate the impact of antegrade SIGN IM nailing start site on radiographic alignment and health-related quality of life. In this prospective cohort study, adult patients with proximal femur fractures (OTA 32, subtrochanteric zone) treated with antegrade IM SIGN nail at Muhimbili Orthopaedic Institute (MOI), Dar es Salaam, Tanzania were enrolled. Start site was determined on the immediate postoperative X-ray and was graded on a continuous scale based on distance of the IM nail center from the greater trochanteric tip. The primary outcome measurement was coronal alignment on the post-operative x-ray. The secondary outcomes were reoperation rates, RUST scores and EQ5D scores at one year follow-up. Seventy-nine patients were enrolled. 50 of them (63.3%) had complete data at 1year and were included in the final data analysis. Of the fifty patients, nine (18%) had IM nails placed laterally, 26 (52%) medially and 15 (30%) directly over the tip of the greater trochanter. Compared to a start site at the tip or medial to the greater trochanter, a lateral start site was 9 times more likely to result in a varus malalignment (95% CI: 1.42-57.70, p=0.021). Lateral start site was associated with varus malalignment. Although lateral start site was not significantly associated with reoperation, varus deformity was associated with higher reoperation rates. Surgeons should consider avoiding a start site lateral to the tip of the greater trochanter or allow the nail to rotate to avoid

  9. Comparison of the OUTBACK®Elite Reentry Catheter and the Bi-directional Approach after Failed Antegrade Approach for Femoro-popliteal Occlusive Disease.

    Science.gov (United States)

    Kawasaki, Daizo; Fukunaga, Masashi; Nakata, Tsuyoshi; Kato, Masaaki; Ohkubo, Nobukazu

    2017-12-01

    A successful antegrade wire crossing for femoro-popliteal chronic total occlusion (FP-CTO) is still a technical challenge. We attempted to demonstrate the safety and feasibility of the OUTBACK ® Elite reentry catheter and the bi-directional approach for failed FP-CTO cases with the antegrade approach. Endovascular therapy for FP-CTO was performed in 219 lesions from May 2013 to December 2016 at Morinomiya Hospital. We retrospectively analyzed the data of 43 consecutive lesions which underwent endovascular therapy using the bi-directional approach with distal access and the mono-directional approach with the OUTBACK ® Elite reentry catheter for FP-CTO lesions. The antegrade success using a combination of traditional and Intravascular Ultrasound (IVUS) -guided techniques was achieved in 170 lesions out of a total of 219 lesions. From May 2013 to June 2016 (phase 1), the bi-directional approach with distal access was applied to 22 lesions after failed antegrade approaches. From July 2016 to December 2016 (phase 2), the mono-directional approach with the OUTBACK ® Elite reentry catheter was applied to 21 lesions. Clinical and lesion characteristics in phase 1 were not significantly different from those in phase 2. The overall initial technical success rate was 100% in both phases. The total wire number and amount of contrast media were significantly less, and the total procedure time and the total fluoroscopic time were significantly shorter in phase 2 than in phase 1 (p<0.01). Endovascular therapy for FP-CTO using the OUTBACK ® Elite reentry catheter is feasible and safe after a failed antegrade approach.

  10. Method of Controlling Steering of a Ground Vehicle

    Science.gov (United States)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)

    2016-01-01

    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  11. Improving Einstein–Podolsky–Rosen steering inequalities with state information

    International Nuclear Information System (INIS)

    Schneeloch, James; Broadbent, Curtis J.; Howell, John C.

    2014-01-01

    We discuss the relationship between entropic Einstein–Podolsky–Rosen (EPR)-steering inequalities and their underlying uncertainty relations along with the hypothesis that improved uncertainty relations lead to tighter EPR-steering inequalities. In particular, we discuss how using information about the state of a quantum system affects one's ability to witness EPR-steering. As an example, we consider the recent improvement to the entropic uncertainty relation between pairs of discrete observables (Berta et al., 2010 [10]). By considering the assumptions that enter into the development of a steering inequality, we derive correct steering inequalities from these improved uncertainty relations and find that they are identical to ones already developed (Schneeloch et al., 2013 [9]). In addition, we consider how one can use state information to improve our ability to witness EPR-steering, and develop a new continuous variable symmetric EPR-steering inequality as a result.

  12. SPS Beam Steering for LHC Extraction

    CERN Document Server

    Gianfelice Wendt, E; Cornelis, K; Norderhaug Drosdal, L; Goddard, B; Kain, V; Meddahi, M; Papaphilippou, Y; Wenninger, J

    2014-01-01

    Beside producing beams for fixed target operation, the CERN Super Proton Synchrotron (SPS) accelerates beams for injection into the Large Hadron Collider (LHC). During the 2012-2013 run drifts of the extracted beam horizontal trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. The feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, has been therefore investigated. The challenges and constraints related to the implementation of such a correction in the SPS are described. Simulation results are presented and a possible operational steering strategy is proposed. As the observed drift is mainly horizontal, the horizontal plane only will be considered.

  13. SPS Beam Steering for LHC Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Gianfelice-Wendt, Eliana [Fermilab; Bartosik, Hannes [CERN; Cornelis, Karel [CERN; Norderhaug Drøsdal, Lene [CERN; Goddard, Brennan [CERN; Kain, Verena [CERN; Meddahi, Malika [CERN; Papaphilippou, Yannis [CERN; Wenninger, Jorg [CERN

    2014-07-01

    The CERN Super Proton Synchrotron accelerates beams for the Large Hadron Collider to 450 GeV. In addition it produces beams for fixed target facilities which adds complexity to the SPS operation. During the run 2012-2013 drifts of the extracted beam trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses in the LHC. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. While extensive studies are going on to understand, and possibly suppress, the source of such SPS orbit drifts the feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, by means of the interlocked correctors, is also being investigated. The challenges and constraints related to the implementation of such a correction in the SPS are described. Simulation results are presented and a possible operational steering strategy is proposed.

  14. Conditional steering under the von Neumann scenario

    Science.gov (United States)

    Mukherjee, Kaushiki; Paul, Biswajit; Karmakar, Sumana; Sarkar, Debasis; Mukherjee, Amit; Bhattacharya, Some Sankar; Roy, Arup

    2017-08-01

    In Phys. Lett. A 166, 293 (1992), 10.1016/0375-9601(92)90711-T, Popescu and Rohrlich characterized nonlocality of pure n -partite entangled systems by studying bipartite violation of local realism when n -2 number of parties perform projective measurements on their particles. A pertinent question in this scenario is whether similar characterization is possible for n -partite mixed entangled states also. In the present work we have followed an analogous approach so as to explore whether given a tripartite mixed entangled state the conditional bipartite states obtained by performing projective measurement on the third party demonstrate a weaker form of nonlocality, quantum steering. We also compare this phenomenon of conditional steering with existing notions of tripartite correlations.

  15. Self-testing through EPR-steering

    International Nuclear Information System (INIS)

    Šupić, Ivan; Hoban, Matty J

    2016-01-01

    The verification of quantum devices is an important aspect of quantum information, especially with the emergence of more advanced experimental implementations of quantum computation and secure communication. Within this, the theory of device-independent robust self-testing via Bell tests has reached a level of maturity now that many quantum states and measurements can be verified without direct access to the quantum systems: interaction with the devices is solely classical. However, the requirements for this robust level of verification are daunting and require high levels of experimental accuracy. In this paper we discuss the possibility of self-testing where we only have direct access to one part of the quantum device. This motivates the study of self-testing via EPR-steering, an intermediate form of entanglement verification between full state tomography and Bell tests. Quantum non-locality implies EPR-steering so results in the former can apply in the latter, but we ask what advantages may be gleaned from the latter over the former given that one can do partial state tomography? We show that in the case of self-testing a maximally entangled two-qubit state, or ebit, EPR-steering allows for simpler analysis and better error tolerance than in the case of full device-independence. On the other hand, this improvement is only a constant improvement and (up to constants) is the best one can hope for. Finally, we indicate that the main advantage in self-testing based on EPR-steering could be in the case of self-testing multi-partite quantum states and measurements. For example, it may be easier to establish a tensor product structure for a particular party’s Hilbert space even if we do not have access to their part of the global quantum system. (paper)

  16. Flexible needle steering for percutaneous therapies.

    Science.gov (United States)

    Glozman, Daniel; Shoham, Moshe

    2006-07-01

    A robotic system is presented for flexible needle steering and control in soft tissue. Flexible needle insertion into a deformable tissue is modeled as a linear beam supported by virtual springs, where the stiffness coefficients of the springs can vary along the needle. Using this simplified model, the forward and inverse kinematics of the needle are solved analytically, thus enabling both path planning and path correction in real time. Given target and obstacle locations, the computer calculates the needle tip trajectory that will avoid the obstacle and hit the target. Using the inverse kinematics algorithm, the corresponding needle base maneuver needed to follow this trajectory is calculated. It is demonstrated that the needle tip path is not unique and can be optimized to minimize lateral pressure of the needle body on the tissue. Needle steering, i.e., the needle base movements that steer the needle tip, is not intuitive. Therefore, the needle insertion procedure is best performed by a robot. The model was verified experimentally on muscle and liver tissues by robotically assisted insertion of a flexible spinal needle. During insertion, the position and shape of the needle were recorded by X-ray. This study demonstrates the ability to curve a flexible needle by its base motion in order to achieve a planned tip trajectory.

  17. Steering Angle Function Algorithm of Morphing of Residential Area

    Directory of Open Access Journals (Sweden)

    XIE Tian

    2015-07-01

    Full Text Available A residential area feature morphing method based on steering angle function is presented. To residential area with the same representation under two different scales,transforming the representation of the residential area polygon from vector coordinates to steering angle function,then using the steering angle function to match,and finding out the similarity and the differences between the residential areas under different scale to get the steering angle function of the the residential areas under any middle scale,the final,transforming the middle scale steering angle function to vector coordinates form,and get the middle shape interpolation of the the residential area polygon.Experimental results show:the residential area morphing method by using steering angle function presented can realize the continuous multi-scale representation under the premise of keeping in shape for the residential area with the rectangular boundary features.

  18. Controlled antegrade intimal tracking with subintimal balloon inflation as a novel bailout technique for chronic total occlusion after failed intravascular ultrasound-guided parallel wire technique.

    Science.gov (United States)

    Imai, Yuta; Yajima, Junji; Hosaka, Fumitaka

    Failure to cross with a guidewire is the most common reason for failure of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). In cases of CTO PCI with no interventional collaterals, an intravascular ultrasound (IVUS)-guided parallel wire technique is usually the last-resort procedure. Failure of this technique sometimes causes enlarged subintimal space, resulting in procedure failure. We present a successful second attempt at left anterior descending artery CTO PCI with no interventional collaterals. After IVUS-guided parallel wire technique failed with an enlarged subintimal space, successful antegrade wire crossing was achieved using controlled antegrade intimal tracking with balloon inflation in the subintimal space to deflect a second wire. This technique may be useful as a bailout strategy in otherwise-failed CTO PCI with an enlarged subintimal space. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Facilitating innovations

    NARCIS (Netherlands)

    Buurma, J.S.; Visser, A.J.; Migchels, G.

    2011-01-01

    Many innovations involve changes which transcend the individual business or are only achievable when various businesses and/or interested parties take up the challenge together. In System Innovation Programmes, the necessary innovations are facilitated by means of workshops related to specific areas

  20. Working paper on public steering of privately owned sports facilities

    DEFF Research Database (Denmark)

    Iversen, Evald Bundgård

    This short paper discusses how municipalities can steer privately owned sports facilities. Firstly I analyse why steering of privately owned facilities is an interesting subject. Secondly I discuss what the advantages and drawbacks of using different approaches for steering sports facilities are....... Finally I discuss the methodological challenges of measuring activities in sports facilities – and take a closer look at the advantages and drawbacks of using manual and thermal techniques for registering activity....

  1. Starclose SE® hemostasis after 6F direct antegrade superficial femoral artery access distal to the femoral head for peripheral endovascular procedures in obese patients.

    Science.gov (United States)

    Spiliopoulos, Stavros; Kitrou, Panagiotis; Christeas, Nikolaos; Karnabatidis, Dimitris

    2016-01-01

    Direct superficial femoral artery (SFA) antegrade puncture is a valid alternative to common femoral artery (CFA) access for peripheral vascular interventions. Data investigating vascular closure device (VCD) hemostasis of distant SFA 6F access are limited. We aimed to investigate the safety and effectiveness of the Starclose SE® VCD for hemostasis, following direct 6F antegrade SFA access distal to the femoral head. This prospective, single-center study included patients who were not suitable for CFA puncture and were scheduled to undergo peripheral endovascular interventions using direct antegrade SFA 6F access, at least 2 cm below the inferior edge of femoral head. Hemostasis was obtained with the Starclose SE® VCD (Abbott Laboratories). Primary endpoints were successful hemostasis rate and periprocedural (30-day) major complication rate. Secondary endpoint was the rate of minor complications. Clinical and Doppler ultrasound follow-up was performed at discharge and at one month. Between September 2014 and August 2015, a total of 30 patients (21 male; 70.0%) with a mean body mass index of 41.2 kg/m2 were enrolled. Mean age was 72±9 years (range, 67-88 years). Most patients suffered from critical limb ischemia (87.1%) and diabetes (61.3%). Calcifications were present in eight cases (26.6%). Reason for direct SFA puncture was obesity (100%). Successful hemostasis was achieved in 100% of the cases. No major complications were noted after one-month follow-up. Minor complications included two hemostasis of antegrade direct SFA puncture. Uncomplicated hemostasis was achieved even in cases of puncturing 2 to 7 cm below the inferior edge of the femoral head.

  2. Stress indicators in steers at slaughtering

    Directory of Open Access Journals (Sweden)

    A. Zarrilli

    2010-04-01

    Full Text Available This work aimed to assess the blood modifications of some slaughtering-linked stress hormones in cattle subject to butcher standardized procedures. The blood samples of 20 Limousine 12-13 months old steers have been collected before slaughtering, during lairage, and after stunning by captive bolt gun, during exsanguination. The plasma level of epinephrine, norepinephrine, cortisol and beta-endorphin have been assayed by EIA. The data indicate that catecholamines, cortisol and beta-endorphin did not significantly increase after stunning in these animals.

  3. Playing facilitator

    DEFF Research Database (Denmark)

    Houmøller, Ellen; Marchetti, Emanuela

    2015-01-01

    workshops based on two classic role-play games: The Silent Game (Brandt, 2006) and The Six Thinking Hats (de Bono, 1985). These games were created to support students in learning design thinking in groups and are assigned positive values in literature, hence we expected a smooth process. However, our......t: This paper presents reflections on the role of teachers as facilitators, in a context of role-play targeting learning of design thinking skills. Our study was conducted according to the method of visual ethnography. We acted as facilitators for 50 students through the yearly six-day competitive...... event called InnoEvent, addressed to students in the fields of multimedia and healthcare. Being interested in studying games and role-play as tools to support independent learning in the field of design thinking and team-building, following Dewey’s (1938) theory of learning experience, we ran two...

  4. Study on control schemes of flexible steering system of a multi-axle all-wheel-steering robot

    Directory of Open Access Journals (Sweden)

    Pingxia Zhang

    2016-05-01

    Full Text Available It is well known that a multi-axle wheeled robot possesses larger load capability and also higher drive performance. However, its steering flexibility is degraded due to the large number of wheels. In order to solve this problem, in this article, we proposed three control schemes based on the center of rotation or the steering angles of both the first- and last-axle wheels. To release these control schemes, steering mode selection and also the left wheel’s steering angle in a specific axle are added approaching a practical application. Thereafter, the remaining wheels’ steering angles can be calculated with the Ackerman steering theorem. In order to verify the control effects, a five-axle all-wheel-steering wheeled robot has been developed with the Bluetooth wireless monitor system. Based on the newly designed robot, validation experiments are carried out, such as lateral movement, situ rotation, and multi-mode steering within a narrow space. The results indicate that the proposed design in this article can ensure a more flexible and faster movement within a narrow space. It shows large potential in obstacle avoidance compared with the conventional partial-wheel steering mode.

  5. Experimental nonlocal steering of Bohmian trajectories.

    Science.gov (United States)

    Xiao, Ya; Kedem, Yaron; Xu, Jin-Shi; Li, Chuan-Feng; Guo, Guang-Can

    2017-06-26

    Interpretations of quantum mechanics (QM), or proposals for underlying theories, that attempt to present a definite realist picture, such as Bohmian mechanics, require strong non-local effects. Naively, these effects would violate causality and contradict special relativity. However if the theory agrees with QM the violation cannot be observed directly. Here, we demonstrate experimentally such an effect: we steer the velocity and trajectory of a Bohmian particle using a remote measurement. We use a pair of photons and entangle the spatial transverse position of one with the polarization of the other. The first photon is sent to a double-slit-like apparatus, where its trajectory is measured using the technique of Weak Measurements. The other photon is projected to a linear polarization state. The choice of polarization state, and the result, steer the first photon in the most intuitive sense of the word. The effect is indeed shown to be dramatic, while being easy to visualize. We discuss its strength and what are the conditions for it to occur.

  6. Optimization Under Uncertainty for Wake Steering Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Quick, Julian [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Annoni, Jennifer [National Renewable Energy Laboratory (NREL), Golden, CO (United States); King, Ryan N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fleming, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ning, Andrew [Brigham Young University

    2017-08-03

    Offsetting turbines' yaw orientations from incoming wind is a powerful tool that may be leveraged to reduce undesirable wake effects on downstream turbines. First, we examine a simple two-turbine case to gain intuition as to how inflow direction uncertainty affects the optimal solution. The turbines are modeled with unidirectional inflow such that one turbine directly wakes the other, using ten rotor diameter spacing. We perform optimization under uncertainty (OUU) via a parameter sweep of the front turbine. The OUU solution generally prefers less steering. We then do this optimization for a 60-turbine wind farm with unidirectional inflow, varying the degree of inflow uncertainty and approaching this OUU problem by nesting a polynomial chaos expansion uncertainty quantification routine within an outer optimization. We examined how different levels of uncertainty in the inflow direction effect the ratio of the expected values of deterministic and OUU solutions for steering strategies in the large wind farm, assuming the directional uncertainty used to reach said OUU solution (this ratio is defined as the value of the stochastic solution or VSS).

  7. Steering healthcare service delivery: a regulatory perspective.

    Science.gov (United States)

    Prakash, Gyan

    2015-01-01

    The purpose of this paper is to explore regulation in India's healthcare sector and makes recommendations needed for enhancing the healthcare service. The literature was reviewed to understand healthcare's regulatory context. To understand the current healthcare system, qualitative data were collected from state-level officials, public and private hospital staff. A patient survey was performed to assess service quality (QoS). Regulation plays a central role in driving healthcare QoS. India needs to strengthen market and institutional co-production based approaches for steering its healthcare in which delivery processes are complex and pose different challenges. This study assesses current healthcare regulation in an Indian state and presents a framework for studying and strengthening regulation. Agile regulation should be based on service delivery issues (pull approach) rather than monitoring and sanctions based regulatory environment (push approach). Healthcare pitfalls across the world seem to follow similar follies. India's complexity and experience is useful for emerging and developed economies. The author reviewed around 70 publications and synthesised them in healthcare regulatory contexts. Patient's perception of private providers could be a key input towards steering regulation. Identifying gaps across QoS dimensions would be useful in taking corrective measures.

  8. Ultrasound-guided antegrade access during laparoscopic pyeloplasty in infants less than one year of age: A point of technique

    Directory of Open Access Journals (Sweden)

    Arvind Ganpule

    2012-01-01

    Full Text Available Background: Access to urethras and ureters of infants may be hazardous and injurious through an endoscopic route. Placement and removal of stents in infants requires anaesthesia and access through these small caliber urethras. We describe our technique of placing antegrade splint during a laparoscopic pyeloplasty in these infants. Materials and Methods: An ultrasound-guided percutaneous renal access is obtained. Telescopic metal two part needle is passed into the kidney over a guide wire. A second guide wire is passed through the telescopic metal two part needle. The tract is dilated with 14 Fr screw dilator. Over one guide wire, a 5 Fr ureteric catheter is passed and coiled in the renal pelvis. Over the other wire, a 14 Fr malecot catheter is placed as nephrostomy. Laparoscopic pyeloplasty is then done. During pyelotomy, the ureteric catheter is pulled and advanced through the ureter before the pyeloplasty is completed. The ureteric catheter thus acts as a splint across the anastomosis. Ureteric catheter is removed on the 3 rd post operative day and nephrostomy is clamped. Nephrostomy is removed on 4 th post operative day if child is asymptomatic. The modified technique was successfully done in five patients aged less than one year old. All patients tolerated the procedure well. Post operative period was uneventful in all. Conclusion: Ultrasound-guided ante grade nephroureteral ureteral splint for infant laparoscopic pyeloplasty is safe. It avoids the need for urethral instrumentation for insertion and removal of stents in these small patients.

  9. 46 CFR 58.25-70 - Steering-gear control systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Steering-gear control systems. 58.25-70 Section 58.25-70... MACHINERY AND RELATED SYSTEMS Steering Gear § 58.25-70 Steering-gear control systems. (a) Each power-driven steering-gear system must be provided with at least one steering-gear control system. (b) The main steering...

  10. 46 CFR 108.641 - Instructions for changing steering gear.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Instructions for changing steering gear. 108.641 Section 108.641 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING... steering gear. Instructions stating, in order, the different steps to be taken for changing to emergency...

  11. Meat quality of weaner steers adapted to a diet containing ...

    African Journals Online (AJOL)

    The objective of the study was to determine the meat quality responses of weaner steers fed diets containing potassium humate (PH) in a feedlot. Twenty-two yearling male steers were randomly allocated to two treatments: control (n = 11), fed a standard feedlot diet and PH (n = 11), fed a standard diet with added PH ...

  12. Steering into the Curve: Getting Real in the Classroom

    Science.gov (United States)

    Uhl, Christopher

    2010-01-01

    Dozens and dozens of little deaths occur in college classrooms each day as teachers, mostly because of fear, steer themselves and their students away from what is alive and real and toward what is dead, safe, and boring. In this paper, I use a collection of stories to describe a practice that enlivens classroom dynamics that I call "Steering Into…

  13. Revisiting path steering for 3D manipulation tasks

    NARCIS (Netherlands)

    L. Liu (Lei); J.-B. Martens; R. van Liere (Robert)

    2011-01-01

    htmlabstractThe law of path steering, as proposed by Accot and Zhai, describes a quantitative relationship between human temporal performance and the path spatial characteristics. The steering law is formulated as a continuous goal crossing task, in which a large number of goals are crossed along

  14. Revisiting path steering for 3D manipulation tasks

    NARCIS (Netherlands)

    L. Liu (Lei); J.-B. Martens; R. van Liere (Robert)

    2010-01-01

    htmlabstractThe law of path steering, as proposed by Accot and Zhai, describes a quantitative relationship between human temporal performance and the path spatial characteristics. The steering law is formulated as a continuous goal crossing task, in which a large number of goals are crossed along

  15. Detailed field test of yaw-based wake steering

    DEFF Research Database (Denmark)

    Fleming, P.; Churchfield, M.; Scholbrock, A.

    2016-01-01

    This paper describes a detailed field-test campaign to investigate yaw-based wake steering. In yaw-based wake steering, an upstream turbine intentionally misaligns its yaw with respect to the inflow to deflect its wake away from a downstream turbine, with the goal of increasing total power produc...

  16. 33 CFR 164.39 - Steering gear: Foreign tankers.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Steering gear: Foreign tankers... (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.39 Steering gear: Foreign tankers... building contract, the keel of which is laid or which is at a similar stage of construction on or after...

  17. Study on the Characteristics of Traction Forces Difference Asymmetric Steering Bogies

    Directory of Open Access Journals (Sweden)

    Yan Shi

    2016-01-01

    Full Text Available This article comes up with a new concept of applying the difference between traction forces on front and rear wheelsets to guiding control, as well as the design of a new type of structurally simple asymmetrical radial bogies, which lead to the proposition of traction forces difference-steering asymmetric radial bogies. The traction forces difference-steering asymmetric radial bogies are referred to as TFDA-bogies, in which the difference of longitudinal creep forces between front and rear wheels produces radial steering of both wheelsets. The concept of traction difference is incorporated into guiding control and bogie structure is also simplified in the form of asymmetrical radial bogies. Angle sensors are mounted to facilitate the change of electric currents of the front and rear traction motors to control the guiding mechanism so that wheelsets can adopt the radial position. With SIMPACK, the multibody dynamics analysis software, three whole vehicle models of TFDA-bogies, radial bogies, and conventional bogies are set up and comparative analyses are made on the lead wheel angle of attack, lead wheel lateral force, lead wheel friction power, and total vehicle friction power under idle running condition and traction condition, respectively. Results show that TFDA-bogies are radial bogies with simplified structure.

  18. High-gradient microelectromechanical system quadrupole electromagnets for particle beam focusing and steering

    Directory of Open Access Journals (Sweden)

    Jere Harrison

    2015-02-01

    Full Text Available Recent advancements in microelectromechanical system (MEMS fabrication techniques have enabled the batch-fabrication of quadrupole MEMS electromagnets producing 100 mT-scale field across sub-mm gaps with the potential for transformational advances in the field of compact high performance charged particle focusing and steering optics. The footprint of these in-vacuum focusing and steering optics can be as small as 3  mm×3  mm×0.5  mm. The low electromagnet impedance (58  mΩ, 32 nH per pole facilitates power-efficient operation and continuous or low duty cycle operation, and the individually controlled electromagnets allow combined dipole-quadrupole fields. Here we report on an experiment where these miniature devices have been used to focus and steer a 34 keV electron beam from a DC photogun, demonstrating the first application of magnetic MEMS to particle beam focusing.

  19. Research on Handling Stability of Steering-by-wire System

    Directory of Open Access Journals (Sweden)

    Yuan Ying

    2017-01-01

    Full Text Available The main function of steer-by-wire (SBW system are improving steering characteristics, security and stability of the vehicle. In this paper, the variable steering ratio of SBW system is analyzed, and the method of steering ratio based on fuzzy control and neural network are researched. In order to solve the actual working condition, the wheel angle may not reach the expected value, this paper establishes a twodegree-of-freedom (2-DOF vehicle model, and a Matlab/Simulink simulation model, in which a control strategy based on PID controller is put forward to control the front wheel steering angle. Simulation results show that proposed control strategy based on fuzzy neural network can effectively reduce lateral deviation and improve the handling stability and comfortability of the vehicle.

  20. Study on classification and identification methods of driver steering characteristics

    Directory of Open Access Journals (Sweden)

    Gang LI

    2015-12-01

    Full Text Available Aiming at the vehicle driver's steering characteristic classification and identification, the research method is initially explored based on CarSim simulation platform. The simulation experiment of steering condition is designed and the test data is collected. According to the maximum yaw rate of the vehicle, the driver steering characteristics are classified by K-means clustering algorithm. The driver steering characteristics identification models are established by learning vector quantization (LVQ neural network, BP neural network, and support vector machine (SVM respectively in the environment of Matlab software. The test experiment and comparison are done for the three kinds of approaches, and the results show that all those three kinds of identification approaches have high accuracy, and the SVM method has a certain advantage on driver steering characteristics identification.

  1. Experimental High-Dimensional Einstein-Podolsky-Rosen Steering

    Science.gov (United States)

    Zeng, Qiang; Wang, Bo; Li, Pengyun; Zhang, Xiangdong

    2018-01-01

    Steering nonlocality is the fundamental property of quantum mechanics, which has been widely demonstrated in some systems with qubits. Recently, theoretical works have shown that the high-dimensional (HD) steering effect exhibits novel and important features, such as noise suppression, which appear promising for potential application in quantum information processing (QIP). However, experimental observation of these HD properties remains a great challenge to date. In this work, we demonstrate the HD steering effect by encoding with orbital angular momentum photons for the first time. More importantly, we have quantitatively certified the noise-suppression phenomenon in the HD steering effect by introducing a tunable isotropic noise. We believe our results represent a significant advance of the nonlocal steering study and have direct benefits for QIP applications with superior capacity and reliability.

  2. Deformable Image Registration based on Similarity-Steered CNN Regression

    Science.gov (United States)

    Cao, Xiaohuan; Yang, Jianhua; Zhang, Jun; Nie, Dong; Kim, Min-jeong; Wang, Qian

    2017-01-01

    Existing deformable registration methods require exhaustively iterative optimization, along with careful parameter tuning, to estimate the deformation field between images. Although some learning-based methods have been proposed for initiating deformation estimation, they are often template-specific and not flexible in practical use. In this paper, we propose a convolutional neural network (CNN) based regression model to directly learn the complex mapping from the input image pair (i.e., a pair of template and subject) to their corresponding deformation field. Specifically, our CNN architecture is designed in a patch-based manner to learn the complex mapping from the input patch pairs to their respective deformation field. First, the equalized active-points guided sampling strategy is introduced to facilitate accurate CNN model learning upon a limited image dataset. Then, the similarity-steered CNN architecture is designed, where we propose to add the auxiliary contextual cue, i.e., the similarity between input patches, to more directly guide the learning process. Experiments on different brain image datasets demonstrate promising registration performance based on our CNN model. Furthermore, it is found that the trained CNN model from one dataset can be successfully transferred to another dataset, although brain appearances across datasets are quite variable. PMID:29250613

  3. Piezo-based, high dynamic range, wide bandwidth steering system for optical applications

    Science.gov (United States)

    Karasikov, Nir; Peled, Gal; Yasinov, Roman; Feinstein, Alan

    2017-05-01

    Piezoelectric motors and actuators are characterized by direct drive, fast response, high positioning resolution and high mechanical power density. These properties are beneficial for optical devices such as gimbals, optical image stabilizers and mirror angular positioners. The range of applications includes sensor pointing systems, image stabilization, laser steering and more. This paper reports on the construction, properties and operation of three types of piezo based building blocks for optical steering applications: a small gimbal and a two-axis OIS (Optical Image Stabilization) mechanism, both based on piezoelectric motors, and a flexure-assisted piezoelectric actuator for mirror angular positioning. The gimbal weighs less than 190 grams, has a wide angular span (solid angle of > 2π) and allows for a 80 micro-radian stabilization with a stabilization frequency up to 25 Hz. The OIS is an X-Y, closed loop, platform having a lateral positioning resolution better than 1 μm, a stabilization frequency up to 25 Hz and a travel of +/-2 mm. It is used for laser steering or positioning of the image sensor, based on signals from a MEMS Gyro sensor. The actuator mirror positioner is based on three piezoelectric actuation axes for tip tilt (each providing a 50 μm motion range), has a positioning resolution of 10 nm and is capable of a 1000 Hz response. A combination of the gimbal with the mirror positioner or the OIS stage is explored by simulations, indicating a <10 micro-radian stabilization capability under substantial perturbation. Simulations and experimental results are presented for a combined device facilitating both wide steering angle range and bandwidth.

  4. Traffic Steering Framework for Mobile-Assisted Resource Management in Heterogeneous Networks

    DEFF Research Database (Denmark)

    Dogadaev, Anton Konstantinovich; Checko, Aleksandra; Popovska Avramova, Andrijana

    2013-01-01

    -Fi or open access small cells. A provision of desired quality of experience to the end-user is carried out by an operator-configurable monitoring application that is running on a mobile device. A potential to enhance network-centric resource management is provided by delegating traffic steering authorities......With the expected growth of mobile data traffic it is essential to manage the network resources efficiently. In order to undertake this challenge, we propose a framework for network-centric, mobile-assisted resource management, which facilitates traffic offloading from mobile network to Wi...

  5. Ligand-induced substrate steering and reshaping of [Ag2(H)]+ scaffold for selective CO2 extrusion from formic acid

    OpenAIRE

    Zavras, Athanasios; Khairallah, George N.; Krsti?, Marjan; Girod, Marion; Daly, Steven; Antoine, Rodolphe; Maitre, Philippe; Mulder, Roger J.; Alexander, Stefanie-Ann; Bona?i?-Kouteck?, Vlasta; Dugourd, Philippe; O'Hair, Richard A. J.

    2016-01-01

    Metalloenzymes preorganize the reaction environment to steer substrate(s) along the required reaction coordinate. Here, we show that phosphine ligands selectively facilitate protonation of binuclear silver hydride cations, [LAg2(H)]+ by optimizing the geometry of the active site. This is a key step in the selective, catalysed extrusion of carbon dioxide from formic acid, HO2CH, with important applications (for example, hydrogen storage). Gas-phase ion-molecule reactions, collision-induced dis...

  6. ATLAS Beam Steering Mechanism (BSM) Lessons Learned

    Science.gov (United States)

    Blumenstock, Kenneth A.; Cramer, Alexander K.; Gosten, Alan B.; Hakun, Claef F.; Haney, Paul G.; Hinkle, Matthew R.; Lee, Kenneth Y.; Lugo, Carlos F.; Matuszeski, Adam J.; Morell, Armando; hide

    2016-01-01

    This paper describes the design, testing, and lessons learned during the development of the Advanced Topographic Laser Altimeter System (ATLAS) Beam Steering Mechanism (BSM). The BSM is a 2 degree-of-freedom tip-tilt mechanism for the purpose of pointing a flat mirror to tightly control the co-alignment of the transmitted laser and the receiver telescope of the ATLAS instrument. The high resolution needs of the mission resulted in sub-arcsecond pointing and knowledge requirements, which have been met. Development of the methodology to verify performance required significant effort. The BSM will fly as part of the Ice, Cloud, and Elevation Satellite II Mission (ICESat II), which is scheduled to be launched in 2017. The ICESat II primary mission is to map the Earth's surface topography for the determination of seasonal changes of ice sheet thickness and vegetation canopy thickness to establish long-term trends.

  7. ATLAS Beam Steering Mechanism Lessons Learned

    Science.gov (United States)

    Blumenstock, Kenneth A.; Cramer, Alexander K.; Gostin, Alan B.; Hakun, Claef F.; Haney, Paul G.; Hinkle, Matthew R.; Lee, Kenneth Y.; Lugo, Carlos F.; Matuszeski, Adam J.; Morrell, Armando; hide

    2016-01-01

    This paper describes the design, testing, and lessons learned during the development of the Advanced Topographic Laser Altimeter System (ATLAS) Beam Steering Mechanism (BSM). The BSM is a 2 degree-of-freedom tip-tilt mechanism for the purpose of pointing a flat mirror to tightly control the co-alignment of the transmitted laser and the receiver telescope of the ATLAS instrument. The high resolution needs of the mission resulted in sub-arcsecond pointing and knowledge requirements, which have been met. Development of the methodology to verify performance required significant effort. The BSM will fly as part of the Ice, Cloud, and Elevation Satellite II Mission (ICESat II), which is scheduled to be launched in 2017. The ICESat II primary mission is to map the earth's surface topography for the determination of seasonal changes of ice sheet thickness and vegetation canopy thickness to establish long-term trends.

  8. Beam Steering Mechanism (BSM) Lessons Learned

    Science.gov (United States)

    Blumenstock, Kenneth A.; Cramer, Alexander K.; Gostin, Alan B.; Hakun, Claef F.; Haney, Paul G.; Hinkle, Matthew R.; Lee, Kenneth Y.; Lugo, Carlos F.; Matuszeski, Adam J.; Morell, Armando; hide

    2016-01-01

    This paper describes the design, testing, and lessons learned during the development of the Advanced Topographic Laser Altimeter System (ATLAS) Beam Steering Mechanism (BSM). The BSM is a 2 degree-of-freedom tip-tilt mechanism for the purpose of pointing a flat mirror to tightly control the co-alignment of the transmitted laser and the receiver telescope of the ATLAS instrument. High resolution needs of the mission resulted in sub-arcsecond pointing and knowledge requirements, which have been met. Development of methodology to verify performance was a significant effortadvancement. The BSM will fly as part of the Ice, Cloud, and Elevation Satellite 2 Mission (ICESat 2), which is scheduled to be launched in 2017. The ICESat 2 primary mission is to map the earths surface topography for the determination of seasonal changes of ice sheet thickness as well as vegetation canopy thickness.

  9. Retrospective Review of Pectoralis Major Ruptures in Rodeo Steer Wrestlers

    Directory of Open Access Journals (Sweden)

    Breda H. F. Lau

    2013-01-01

    Full Text Available Background. Pectoralis major tendon ruptures have been reported in the literature as occupational injuries, accidental injuries, and sporting activities. Few cases have been reported with respect to rodeo activities. Purpose. To describe a series of PM tendon ruptures in professional steer wrestlers. Study Design. Case series, level of evidence, 4. Methods. A retrospective analysis of PM ruptures in a steer wrestling cohort was performed. Injury data between 1992 and 2008 were reviewed using medical records from the University of Calgary Sport Medicine Center. Results. Nine cases of pectoralis major ruptures in professional steer wrestlers were identified. Injuries occurred during the throwing phase of the steer or while breaking a fall. All athletes reported unexpected or abnormal behavior of the steer that contributed to the mechanism of injury. Seven cases were surgically repaired, while two cases opted for nonsurgical intervention. Eight cases reported successful return to competition following the injury. Conclusion. Steer wrestlers represent a unique cohort of PM rupture case studies. Steer wrestling is a demanding sport that involves throwing maneuvers that may predispose the muscle to rupture. All cases demonstrated good functional outcomes regardless of surgical or non-surgical treatment.

  10. Directional control-response compatibility of joystick steered shuttle cars.

    Science.gov (United States)

    Burgess-Limerick, Robin; Zupanc, Christine M; Wallis, Guy

    2012-01-01

    Shuttle cars are an unusual class of vehicle operated in underground coal mines, sometimes in close proximity to pedestrians and steering errors may have very serious consequences. A directional control-response incompatibility has previously been described in shuttle cars which are controlled using a steering wheel oriented perpendicular to the direction of travel. Some other shuttle car operators are seated perpendicular to the direction of travel and steer the car via a seat mounted joystick. A virtual simulation was utilised to determine whether the steering arrangement in these vehicles maintains directional control-response compatibility. Twenty-four participants were randomly assigned to either a condition corresponding to this design (consistent direction), or a condition in which the directional steering response was reversed while driving in-bye (visual field compatible). Significantly less accurate steering performance was exhibited by the consistent direction group during the in-bye trials only. Shuttle cars which provide the joystick steering mechanism described here require operators to accommodate alternating compatible and incompatible directional control-response relationships with each change of car direction. A virtual simulation of an underground coal shuttle car demonstrates that the design incorporates a directional control-response incompatibility when driving the vehicle in one direction. This design increases the probability of operator error, with potential adverse safety and productivity consequences.

  11. Comparing study with two venous approaches of antegrade catheterization for thrombolysis in acute iliofemoral deep vein thrombosis

    International Nuclear Information System (INIS)

    Su Haobo; Gu Jianping; Lou Wensheng; He Xu; Chen Liang; Chen Guoping; Song Jinhua; Wang Tao

    2008-01-01

    Objective: To evaluate the clinical effectiveness of catheterization via the great saphenous vein for thrombolysis in acute iliofemoral deep vein thrombosis (IFVT). Methods: Patients with documented acute iliofemoral deep vein thrombosis were divided into two groups. Patients in group A received CDT with venous access through the ipsilateral great saphenous vein. The patients in group B received CDT via the ipsilateral popliteal vein. Clinical efficacy was evaluated by measuring the circumferences between the normal and affected limbs before and after treatment; the venous patency score, the rate of patency improvement based on venographic results; and the clinical results including the limbs edema reduction rate, the mean punctuation duration and complications; were all compared between the two groups. Results: The total effective rates between group A and group B showed no significant difference (95.2% vs 96%, P = 0.549); including the limbs edema reduction rates(86.6 ± 20.0% vs 85.7 ± 14.6%, P=0.868), likewise, the rates of venous patency improvement(57.9 ± 19.4% vs 57.7 ± 19.3%, P=0.968). The mean punctuation duration of group A was remarkable less than that of group B (7.3 minutes vs 16.7 minutes, P<0.05). The incidence of complications at the site of insertion in group A was lower than that in group B (P<0.05). Conclusions: The great saphenous vein is a new alternative access site for antegrade catheterization in catheter-directed thrombolysis for treatment of acute IFVT; more convenient and safe than popliteal venous approach. (authors)

  12. Low-flow antegrade cerebral perfusion attenuates early renal and intestinal injury during neonatal aortic arch reconstruction.

    Science.gov (United States)

    Algra, Selma O; Schouten, Antonius N J; van Oeveren, Wim; van der Tweel, Ingeborg; Schoof, Paul H; Jansen, Nicolaas J G; Haas, Felix

    2012-12-01

    Deep hypothermic circulatory arrest (DHCA) and antegrade cerebral perfusion (ACP) are 2 cardiopulmonary bypass strategies mainly used in aortic arch reconstructions. It has been suggested that during ACP, abdominal organs are better protected than during DHCA owing to partial perfusion via collaterals. We tested this hypothesis using intraoperative near-infrared spectroscopy (NIRS), lactate measurements, and biomarkers for early abdominal injury in neonates undergoing complex aortic arch repair. Neonates scheduled for aortic arch reconstruction via median sternotomy between 2009 and 2011 were randomized to either DHCA or ACP. During surgery, regional oxygen saturations of the abdomen were monitored using NIRS. Immediately aafter DHCA or ACP, lactate concentrations from the inferior vena cava were compared with those from the arterial cannula. Postoperatively, biomarkers for early abdominal organ injury were measured in urine. Twenty-five neonates were analyzed (DHCA, n = 12; ACP, n = 13). Procedures were performed at 18°C, and ACP flow was set at 35 to 50 mL · kg(-1) · min(-1). Median abdominal NIRS value during DHCA was 31% (IQR, 28%-41%) whereas during ACP it was 56% (IQR, 34%-64%; P intestinal damage (gluthatione s-transferase and intestinal fatty acid binding protein, respectively) were higher in the DHCA group than for the ACP group (P = .03, P = .04, respectively). These results substantiate earlier suggestions that ACP provides more abdominal organ protection than DHCA in neonates undergoing aortic arch reconstruction. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  13. Multiquantum well beam-steering device for laser satellite communication

    Science.gov (United States)

    Lahat, Roee; Levy, Itamar; Shlomi, Arnon

    2002-01-01

    With the increasing interest in laser satellite communications, new methods are sought to solve the existing problems of accurate and rapid laser beam deflection. Current solutions in the form of galvanometers or piezo fast steering mirrors with one or two degrees of freedom are bulky, power-consuming and slow. The Multi-Quantum Well (MQW) is a semiconductor device with unique potential to steer laser beams without any moving parts. We have conducted a preliminary evaluation of the potential application of the MQW as a laser beam-steering device for laser satellite communication, examining the performance of critical parameters for this type of communications.

  14. Retrograde pedal access with a 20-gauge intravenous cannula after failed antegrade recanalization of a tibialis anterior artery in a diabetic patient: a case report

    Directory of Open Access Journals (Sweden)

    Yucel Colkesen

    2015-08-01

    Full Text Available Retrograde tibiopedal approach is being used frequently in below-the-knee vascular interventions. In patients with diabetic foot pathology, complex anatomy often requires a retrograde technique when the distal vascular anatomy and puncture site is suitable. The dorsalis pedis and posterior tibial arteries can be punctured because of their relatively superficial position. We report a retrograde puncturing technique in patients with chronic total occlusions. After failed antegrade recanalization, puncturing and cannulation of a tiny dorsalis pedis artery with a narrow bore [20-gauge (0.8 mm] intravenous cannula is described.

  15. 46 CFR 130.130 - Steering on OSVs of less than 100 gross tons.

    Science.gov (United States)

    2010-10-01

    ... main steering gear must be available from the pilothouse, including control of any necessary ancillary device (motor, pump, valve, or the like). If a power-driven main steering gear is used, a pilot light... main means of steering (main steering gear) must be— (1) Of adequate strength for, and capable of...

  16. Energetic funnel facilitates facilitated diffusion.

    Science.gov (United States)

    Cencini, Massimo; Pigolotti, Simone

    2018-01-25

    Transcription factors (TFs) are able to associate to their binding sites on DNA faster than the physical limit posed by diffusion. Such high association rates can be achieved by alternating between three-dimensional diffusion and one-dimensional sliding along the DNA chain, a mechanism-dubbed facilitated diffusion. By studying a collection of TF binding sites of Escherichia coli from the RegulonDB database and of Bacillus subtilis from DBTBS, we reveal a funnel in the binding energy landscape around the target sequences. We show that such a funnel is linked to the presence of gradients of AT in the base composition of the DNA region around the binding sites. An extensive computational study of the stochastic sliding process along the energetic landscapes obtained from the database shows that the funnel can significantly enhance the probability of TFs to find their target sequences when sliding in their proximity. We demonstrate that this enhancement leads to a speed-up of the association process. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Steering of Solar Sails Using Optical Lift Force Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This study seeks to look beyond the use of radiation pressure for thrust, and to explore a means of solar navigation whereby a solar craft would be steered by use...

  18. Real-Time Application Performance Steering and Adaptive Control

    National Research Council Canada - National Science Library

    Reed, Daniel

    2002-01-01

    .... The objective of the Real-time Application Performance Steering and Adaptive Control project is to replace ad hoc, post-mortem performance optimization with an extensible, portable, and distributed...

  19. CCCT - NCTN Steering Committees - Pediatric and Adolescent Tumor

    Science.gov (United States)

    The Pediatric and Adolescent Solid Tumor Steering Committee addresses the design, prioritization and evaluation of concepts for large phase 2 and phase 3 clinical trials in extracranial solid tumors of children and youth.

  20. Studies of aggregated nanoparticles steering during magnetic-guided drug delivery in the blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Hoshiar, Ali Kafash [School of Mechanical and Aerospace Engineering and ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Faculty of Industrial and Mechanical Engineering, Islamic Azad University, Qazvin Branch, Qazvin (Iran, Islamic Republic of); Le, Tuan-Anh [School of Mechanical and Aerospace Engineering and ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Amin, Faiz Ul [Department of Biology and Applied Life Science, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Kim, Myeong Ok, E-mail: mokim@gnu.ac.kr [Department of Biology and Applied Life Science, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Yoon, Jungwon, E-mail: jwyoon@gnu.ac.kr [School of Mechanical and Aerospace Engineering and ReCAPT, Gyeongsang National University, Jinju 660-701 (Korea, Republic of)

    2017-04-01

    Magnetic-guided targeted drug delivery (TDD) systems can enhance the treatment of diverse diseases. Despite the potential and promising results of nanoparticles, aggregation prevents precise particle guidance in the vasculature. In this study, we developed a simulation platform to investigate aggregation during steering of nanoparticles using a magnetic field function. The magnetic field function (MFF) comprises a positive and negative pulsed magnetic field generated by electromagnetic coils, which prevents adherence of particles to the vessel wall during magnetic guidance. A commonly used Y-shaped vessel was simulated and the performance of the MFF analyzed; the experimental data were in agreement with the simulation results. Moreover, the effects of various parameters on magnetic guidance were evaluated and the most influential identified. The simulation results presented herein will facilitate more precise guidance of nanoparticles in vivo. - Highlights: • We developed a simulation platform to investigate aggregation of nanoparticles. • The influential parameters for magnetic steering of a Y-shaped vessel were identified. • The proposed platform will facilitate more precise guidance of nanoparticles in vivo.

  1. Calculation of the beam injector steering system using Helmholtz coils

    International Nuclear Information System (INIS)

    Passaro, A.; Sircilli Neto, F.; Migliano, A.C.C.

    1991-03-01

    In this work, a preliminary evaluation of the beam injector steering system of the IEAv electron linac is presented. From the existing injector configuration and with the assumptions of monoenergetic beam (100 keV) and uniform magnetic field, two pairs of Helmholtz coils were calculated for the steering system. Excitations of 105 A.turn and 37 A.turn were determined for the first and second coils, respectively. (author)

  2. Role of thermal noise in tripartite quantum steering

    OpenAIRE

    Wang, Meng; Gong, Qihuang; Ficek, Zbigniew; He, Qiongyi

    2014-01-01

    The influence of thermal noise on bipartite and tripartite quantum steering induced by a short laser pulse in a hybrid three-mode optomechanical system is investigated. The calculation is carried out under the bad cavity limit, the adiabatic approximation of a slowly varying amplitude of the cavity mode, and with the assumption of driving the cavity mode with a blue detuned strong laser pulse. Under such conditions, explicit expressions of the bipartite and tripartite steering parameters are ...

  3. A novel estimating method for steering efficiency of the driver with electromyography signals

    Science.gov (United States)

    Liu, Yahui; Ji, Xuewu; Hayama, Ryouhei; Mizuno, Takahiro

    2014-05-01

    The existing research of steering efficiency mainly focuses on the mechanism efficiency of steering system, aiming at designing and optimizing the mechanism of steering system. In the development of assist steering system especially the evaluation of its comfort, the steering efficiency of driver physiological output usually are not considered, because this physiological output is difficult to measure or to estimate, and the objective evaluation of steering comfort therefore cannot be conducted with movement efficiency perspective. In order to take a further step to the objective evaluation of steering comfort, an estimating method for the steering efficiency of the driver was developed based on the research of the relationship between the steering force and muscle activity. First, the steering forces in the steering wheel plane and the electromyography (EMG) signals of the primary muscles were measured. These primary muscles are the muscles in shoulder and upper arm which mainly produced the steering torque, and their functions in steering maneuver were identified previously. Next, based on the multiple regressions of the steering force and EMG signals, both the effective steering force and the total force capacity of driver in steering maneuver were calculated. Finally, the steering efficiency of driver was estimated by means of the estimated effective force and the total force capacity, which represented the information of driver physiological output of the primary muscles. This research develops a novel estimating method for driver steering efficiency of driver physiological output, including the estimation of both steering force and the force capacity of primary muscles with EMG signals, and will benefit to evaluate the steering comfort with an objective perspective.

  4. Optimization Under Uncertainty for Wake Steering Strategies: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Quick, Julian [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Annoni, Jennifer [National Renewable Energy Laboratory (NREL), Golden, CO (United States); King, Ryan N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fleming, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ning, Andrew [Brigham Young University

    2017-05-01

    Wind turbines in a wind power plant experience significant power losses because of aerodynamic interactions between turbines. One control strategy to reduce these losses is known as 'wake steering,' in which upstream turbines are yawed to direct wakes away from downstream turbines. Previous wake steering research has assumed perfect information, however, there can be significant uncertainty in many aspects of the problem, including wind inflow and various turbine measurements. Uncertainty has significant implications for performance of wake steering strategies. Consequently, the authors formulate and solve an optimization under uncertainty (OUU) problem for finding optimal wake steering strategies in the presence of yaw angle uncertainty. The OUU wake steering strategy is demonstrated on a two-turbine test case and on the utility-scale, offshore Princess Amalia Wind Farm. When we accounted for yaw angle uncertainty in the Princess Amalia Wind Farm case, inflow-direction-specific OUU solutions produced between 0% and 1.4% more power than the deterministically optimized steering strategies, resulting in an overall annual average improvement of 0.2%. More importantly, the deterministic optimization is expected to perform worse and with more downside risk than the OUU result when realistic uncertainty is taken into account. Additionally, the OUU solution produces fewer extreme yaw situations than the deterministic solution.

  5. Steering innovations towards a green economy

    NARCIS (Netherlands)

    Droste, N.; Hansjürgens, B.; Kuikman, P.; Otter, N.; Antikainen, R.; Leskinen, P.; Pitkänen, K.; Saikku, L.; Loiseau, E.; Thomsen, M.

    2016-01-01

    In this paper we analyse institutional conditions facilitating the transition towards a green economy by encouraging investment in the enhancement of natural capital and social equity, focussing especially on government interventions. Presenting a conceptual institutional model how innovation

  6. Definition of a safe zone for antegrade lag screw fixation of fracture of posterior column of the acetabulum by 3D technology.

    Science.gov (United States)

    Feng, Xiaoreng; Zhang, Sheng; Luo, Qiang; Fang, Jintao; Lin, Chaowen; Leung, Frankie; Chen, Bin

    2016-03-01

    The objective of this study was to define a safe zone for antegrade lag screw fixation of fracture of posterior column of the acetabulum using a novel 3D technology. Pelvic CT data of 59 human subjects were obtained to reconstruct three-dimensional (3D) models. The transparency of 3D models was then downgraded along the axial perspective (the view perpendicular to the cross section of the posterior column axis) to find the largest translucent area. The outline of the largest translucent area was drawn on the iliac fossa. The line segments of OA, AB, OC, CD, the angles of OAB and OCD that delineate the safe zone (ABDC) were precisely measured. The resultant line segments OA, AB, OC, CD, and angles OAB and OCD were 28.46mm(13.15-44.97mm), 45.89mm (34.21-62.85mm), 36.34mm (18.68-55.56mm), 53.08mm (38.72-75.79mm), 37.44° (24.32-54.96°) and 55.78° (43.97-79.35°) respectively. This study demonstrates that computer-assisted 3D modelling techniques can aid in the precise definition of the safe zone for antegrade insertion of posterior column lag screws. A full-length lag screw can be inserted into the zone (ABDC), permitting a larger operational error. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Membranous IVC Obstruction Presenting with Antegrade/Retrograde Respiratory Flow in the Intrahepatic Segment in Doppler Imaging and Prostatic and Urethral Congestion

    International Nuclear Information System (INIS)

    Sood, Dinesh; Mistry, Kewal A.; Chadha, Veenal; Sharma, Sarthak; Morey, Parikshit D.; Suthar, Pokhraj P.; Patel, Dhruv G.

    2015-01-01

    Obstruction of the inferior vena cava (IVC) is infrequent, membranous obstruction of the IVC (MOIVC) being one of its rare causes. Early diagnosis is important, as it can lead to hepatic congestion, cirrhosis and Budd-Chiari syndrome (BCS) and can predispose to development of hepatocellular carcinoma (HCC) in severe cases. We report a case of membranous IVC obstruction at the junction of hepatic and suprahepatic segments in a young male with extensive collateralization and venous aneurysms. Unique findings involved antegrade and retrograde flow during respiration in the upper part of intrahepatic IVC proximal to a large collateral vein as well as prostatic and urethral congestion leading to intermittent urinary hesitancy, which have not yet been described in such cases. MOIVC is a rare cause of IVC obstruction with typical radiological features. Early diagnosis and management is required due to risk of cirrhosis and HCC. Antegrade and retrograde flow may be seen in incomplete MOIVC above the level of a large collateral vein and it may lead to prostatic and urethral congestion

  8. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths in antegrade and crossover procedures: midterm results

    International Nuclear Information System (INIS)

    Dorffner, Roland; Neumann, Christian; Gergely, Istvan; Renner, Reinhold; Resinger, Mathias; Juhasz, Max; Dorffner, Georg

    2003-01-01

    The aim of this study was to evaluate the technical performance of the implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths. Thirty-three lesions (24 stenoses, 9 occlusions) in 32 patients (mean age 67 years) were stented. Selective stent implantation was performed after unsatisfactory percutaneous transluminal angioplasty result with an antegrade access in 21 patients and through a crossover sheath in 11 patients. A total of 36 stents were implanted. Stent delivery was successful in all cases (stent diameter 5 or 6 mm, stent length 11-38 mm). In none of the cases was stent dislodgement from the balloon observed. Stent placement was optimal without residual stenosis in 30 cases. In 1 case the stent was chosen too short requiring implantation of a second stent. In 1 patient distal embolization was observed which was treated with catheter embolectomy. Nine-month primary and secondary patency rates were 79±8.7 and 86±7.7%, respectively. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths is safe in antegrade and crossover procedures. (orig.)

  9. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths in antegrade and crossover procedures: midterm results

    Energy Technology Data Exchange (ETDEWEB)

    Dorffner, Roland; Neumann, Christian; Gergely, Istvan [Department of Radiology, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Renner, Reinhold; Resinger, Mathias [Department of Surgery, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Juhasz, Max [Department of Internal Medicine, Hospital of the Brothers of St. John, Esterhazystrasse 26, 7000, Eisenstadt (Austria); Dorffner, Georg [Department of Medical Cybernetics and Artificial Intelligence, University of Vienna, Freyung 6/2, 1010, Vienna (Austria)

    2003-11-01

    The aim of this study was to evaluate the technical performance of the implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths. Thirty-three lesions (24 stenoses, 9 occlusions) in 32 patients (mean age 67 years) were stented. Selective stent implantation was performed after unsatisfactory percutaneous transluminal angioplasty result with an antegrade access in 21 patients and through a crossover sheath in 11 patients. A total of 36 stents were implanted. Stent delivery was successful in all cases (stent diameter 5 or 6 mm, stent length 11-38 mm). In none of the cases was stent dislodgement from the balloon observed. Stent placement was optimal without residual stenosis in 30 cases. In 1 case the stent was chosen too short requiring implantation of a second stent. In 1 patient distal embolization was observed which was treated with catheter embolectomy. Nine-month primary and secondary patency rates were 79{+-}8.7 and 86{+-}7.7%, respectively. Implantation of the Corinthian IQ stent into the femoropopliteal arteries using 6-F introducer sheaths is safe in antegrade and crossover procedures. (orig.)

  10. NGF steers microglia toward a neuroprotective phenotype.

    Science.gov (United States)

    Rizzi, Caterina; Tiberi, Alexia; Giustizieri, Michela; Marrone, Maria Cristina; Gobbo, Francesco; Carucci, Nicola Maria; Meli, Giovanni; Arisi, Ivan; D'Onofrio, Mara; Marinelli, Silvia; Capsoni, Simona; Cattaneo, Antonino

    2018-02-23

    Microglia are the sentinels of the brain but a clear understanding of the factors that modulate their activation in physiological and pathological conditions is still lacking. Here we demonstrate that Nerve Growth Factor (NGF) acts on microglia by steering them toward a neuroprotective and anti-inflammatory phenotype. We show that microglial cells express functional NGF receptors in vitro and ex vivo. Our transcriptomic analysis reveals how, in primary microglia, NGF treatment leads to a modulation of motility, phagocytosis and degradation pathways. At the functional level, NGF induces an increase in membrane dynamics and macropinocytosis and, in vivo, it activates an outward rectifying current that appears to modulate glutamatergic neurotransmission in nearby neurons. Since microglia are supposed to be a major player in Aβ peptide clearance in the brain, we tested the effects of NGF on its phagocytosis. NGF was shown to promote TrkA-mediated engulfment of Aβ by microglia, and to enhance its degradation. Additionally, the proinflammatory activation induced by Aβ treatment is counteracted by the concomitant administration of NGF. Moreover, by acting specifically on microglia, NGF protects neurons from the Aβ-induced loss of dendritic spines and inhibition of long term potentiation. Finally, in an ex-vivo setup of acute brain slices, we observed a similar increase in Aβ engulfment by microglial cells under the influence of NGF. Our work substantiates a role for NGF in the regulation of microglial homeostatic activities and points toward this neurotrophin as a neuroprotective agent in Aβ accumulation pathologies, via its anti-inflammatory activity on microglia. © 2018 The Authors GLIA Published by Wiley Periodicals, Inc.

  11. BEAMLINE-CONTROLLED STEERING OF SOURCE-POINT ANGLE AT THE ADVANCED PHOTON SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Emery, L.; Fystro, G.; Shang, H.; Smith, M.

    2017-06-25

    An EPICS-based steering software system has been implemented for beamline personnel to directly steer the angle of the synchrotron radiation sources at the Advanced Photon Source. A script running on a workstation monitors "start steering" beamline EPICS records, and effects a steering given by the value of the "angle request" EPICS record. The new system makes the steering process much faster than before, although the older steering protocols can still be used. The robustness features of the original steering remain. Feedback messages are provided to the beamlines and the accelerator operators. Underpinning this new steering protocol is the recent refinement of the global orbit feedback process whereby feedforward of dipole corrector set points and orbit set points are used to create a local steering bump in a rapid and seamless way.

  12. Asymmetries in wing inertial and aerodynamic torques contribute to steering in flying insects.

    Science.gov (United States)

    Jankauski, Mark; Daniel, T L; Shen, I Y

    2017-06-08

    Maneuvering in both natural and artificial miniature flying systems is assumed to be dominated by aerodynamic phenomena. To explore this, we develop a flapping wing model integrating aero and inertial dynamics. The model is applied to an elliptical wing similar to the forewing of the Hawkmoth Manduca sexta and realistic kinematics are prescribed. We scrutinize the stroke deviation phase, as it relates to firing latency in airborne insect steering muscles which has been correlated to various aerial maneuvers. We show that the average resultant force production acting on the body largely arises from wing pitch and roll and is insensitive to the phase and amplitude of stroke deviation. Inclusion of stroke deviation can generate significant averaged aerodynamic torques at steady-state and adjustment of its phase can facilitate body attitude control. Moreover, averaged wing angular momentum varies with stroke deviation phase, implying a non-zero impulse during a time-dependent phase shift. Simulations show wing inertial and aerodynamic impulses are of similar magnitude during short transients whereas aerodynamic impulses dominate during longer transients. Additionally, inertial effects become less significant for smaller flying insects. Body yaw rates arising from these impulses are consistent with biologically measured values. Thus, we conclude (1) modest changes in stroke deviation can significantly affect steering and (2) both aerodynamic and inertial torques are critical to maneuverability, the latter of which has not widely been considered. Therefore, the addition of a control actuator modulating stroke deviation may decouple lift/thrust production from steering mechanisms in flapping wing micro aerial vehicles and increase vehicle dexterity through inertial trajectory shaping.

  13. Sources of carbohydrates in the ingestive behavior of feedlot steers

    Directory of Open Access Journals (Sweden)

    Viviane Santos da Silva

    2014-05-01

    Full Text Available In this article we research the influence of different sources of carbohydrates (corn, soybean hulls or wheat bran upon the digestive behavior of 24 confined castrated steers with an initial average age and weight of 20 months and 330 kg born from the cross between Charolais and Nellore. The diet was composed of 40% sorghum silage and 60% concentrate. The time spent on total ruminating (an average of 454.6 min/day was not influenced by the source of carbohydrate. The animals from the wheat bran treatment spent less time idle (718 min in relation to those on the corn and soybean hulls treatments, which did not differ between themselves (an average of 792 min/day. The steers from the wheat bran treatment remained less time feeding (184 min/day compared with those fed the other treatments, whose average time of permanence in this activity was 214 minutes per day. The other studied variables did not present a significant difference between the treatments. Inclusion of wheat bran in the diet of the confined steers results in less spent time idle, while steers feeding on soybean hulls spend less time feeding. The use of corn, soybean hulls, or wheat bran in the diet of the confined steers does not affect the total cudding time.

  14. Large impacted upper ureteral calculi: A comparative study between retrograde ureterolithotripsy and percutaneous antegrade ureterolithotripsy in the modified lateral position.

    Science.gov (United States)

    Moufid, Kamal; Abbaka, Najib; Touiti, Driss; Adermouch, Latifa; Amine, Mohamed; Lezrek, Mohammed

    2013-07-01

    The treatment for patients with large impacted proximal ureteral stone remains controversial, especially at institutions with limited resources. The aim of this study is to compare and to evaluate the outcome and complications of two main treatment procedures for impacted proximal ureteral calculi, retrograde ureterolithotripsy (URS), and percutaneous antegrade ureterolithotripsy (Perc-URS). Our inclusion criteria were solitary, radiopaque calculi, >15 mm in size in a functioning renal unit. Only those patients in whom the attempt at passing a guidewire or catheter beyond the calculus failed were included in this study. Between January 2007 and July 2011, a total of 52 patients (13 women and 39 men) with large impacted upper-ureteral calculi >15 mm and meeting the inclusion criteria were selected. Of these, Perc-URS was done in 22 patients (group 1) while retrograde ureteroscopy was performed in 30 patients (group 2). We analyzed operative time, incidence of complications during and after surgery, the number of postoperative recovery days, median total costs associated per patient per procedure, and the stone-free rate immediately after 5 days and after 1 month. Bivariate analysis used the Student t-test and the Mann-Whitney test to compare two means and Chi-square and Fisher's exact tests to compare two percentages. The significance level was set at 0.05. The mean age was 42.3 years (range 22-69). The mean stone sizes (mm) were 34 ± 1.2 and 29.3 ± 1.8 mm in group 1 and 2, respectively. In the Perc-URS group, 21 patients (95.45%) had complete calculus clearance through a single tract in one session of percutaneous surgery, whereas in the URS group, only 20 patients (66.7%) had complete stone clearance (P = 0.007). The mean operative time was higher in the Perc-URS group compared to group 2 (66.5 ± 21.7 vs. 52.13 ± 17.3 min, respectively; P = 0.013). Complications encountered in group 1 included transient postoperative fever (2 pts) and simple urine outflow (2

  15. Polarjugend.de - an IPY Education and Outreach Project of the German Youth Steering Committee

    Science.gov (United States)

    Sachs, T.; Kaiser, B.; Richter, A.; Schofield, R.; Lantuit, H.; Salmon, R.; Haase, D.

    2007-12-01

    The online network polarjugend.de is a project being initiated by the German Youth Steering Committee for the International Polar Year (GYSC) in cooperation with the International Youth Steering Committe and the IPY Education and Outreach. Two goals integral to the YSC are firstly the networking of young polar researchers across all disciplines early in their careers to enable collaboration, and secondly for this network to be involved in outreach to other youth. To meet these two aims with a project coordinated by the youth for the youth, the German YSC has created an online platform in German to facilitate the collaboration among high-school students, teachers and young polar researchers in and outside the classroom. The GYSC coordinates presentations and discussions at high schools throughout Germany by networking teachers and researchers and providing educational material and resources. The GYSC makes available brief online presentations and articles for further use in the classroom. An event calendar provides teachers and students with subject-relevant information on the Polar Regions. An online discussion forum considers student questions dealing with polar issues. The project aims at reducing the language barrier of polar education and outreach activities for a German- speaking audience by providing polar-related information and further means of communication specifically in German. The project is designed to continue beyond the timeline of the IPY, and the GYSC is confident that it will exert a lasting effect on German high-school education and the integration and discussion of Polar issues into the curriculum.

  16. Signal Processing Strategies for Cochlear Implants Using Current Steering

    Directory of Open Access Journals (Sweden)

    Waldo Nogueira

    2009-01-01

    Full Text Available In contemporary cochlear implant systems, the audio signal is decomposed into different frequency bands, each assigned to one electrode. Thus, pitch perception is limited by the number of physical electrodes implanted into the cochlea and by the wide bandwidth assigned to each electrode. The Harmony HiResolution bionic ear (Advanced Bionics LLC, Valencia, CA, USA has the capability of creating virtual spectral channels through simultaneous delivery of current to pairs of adjacent electrodes. By steering the locus of stimulation to sites between the electrodes, additional pitch percepts can be generated. Two new sound processing strategies based on current steering have been designed, SpecRes and SineEx. In a chronic trial, speech intelligibility, pitch perception, and subjective appreciation of sound were compared between the two current steering strategies and standard HiRes strategy in 9 adult Harmony users. There was considerable variability in benefit, and the mean results show similar performance with all three strategies.

  17. A spatial filtering approach to electronic wideband beam steering

    Science.gov (United States)

    Liu, Wei; Morgan, Dennis R.

    2011-06-01

    In wideband beam steering, when we need to change the beam direction frequently, the most convenient and flexible way is through digital circuits via FIR/IIR filtering. However this becomes infeasible when the signal frequency and bandwidth are extremely high. To solve this problem, instead of sampling the signals in the temporal domain for digital processing, we sample the signals spatially with more sensors positioned behind the original array of sensors. The spatially sampled signals are then processed using simple analogue circuits (variable gain amplifiers) to form the required steering delays. The delay between the spatially sampled signals is dependent on the sensor spacing and the directions of the designed beams, and is not limited by signal frequency. Design examples are provided to show that different delays can be effectively realised by a spatial filtering system to steer a nominal beam to required directions.

  18. Dissipation induced asymmetric steering of distant atomic ensembles

    Science.gov (United States)

    Cheng, Guangling; Tan, Huatang; Chen, Aixi

    2018-04-01

    The asymmetric steering effects of separated atomic ensembles denoted by the effective bosonic modes have been explored by the means of quantum reservoir engineering in the setting of the cascaded cavities, in each of which an atomic ensemble is involved. It is shown that the steady-state asymmetric steering of the mesoscopic objects is unconditionally achieved via the dissipation of the cavities, by which the nonlocal interaction occurs between two atomic ensembles, and the direction of steering could be easily controlled through variation of certain tunable system parameters. One advantage of the present scheme is that it could be rather robust against parameter fluctuations, and does not require the accurate control of evolution time and the original state of the system. Furthermore, the double-channel Raman transitions between the long-lived atomic ground states are used and the atomic ensembles act as the quantum network nodes, which makes our scheme insensitive to the collective spontaneous emission of atoms.

  19. Current steering effect of GaN nanoporous structure

    International Nuclear Information System (INIS)

    Lin, Chia-Feng; Wang, Jing-Hao; Cheng, Po-Fu; Tseng, Wang-Po; Fan, Feng-Hsu; Wu, Kaun-Chun; Lee, Wen-Che; Han, Jung

    2014-01-01

    Current steering effect of InGaN light emitting diode (LED) structure was demonstrated by forming a high resistivity GaN nanoporous structure. Disk-array patterns with current-injection bridge structures were fabricated on InGaN LED devices through a focused ion beam (FIB) system. GaN nanoporous structure was formed around the FIB-drilled holes through a electrochemical (EC) wet-etching process on a n-type GaN:Si layer under the InGaN active layer. High emission intensity and small peak wavelength blueshift phenomenon of the electroluminescence spectra were observed in the EC-treated region compared with the non-treated region. The branch-like nanoporous structure was formed along the lateral etched direction to steer the injection current in 5 μm-width bridge structures. In the FIB-drilled hole structure, high light emission intensity of the central-disk region was observed by enlarging the bridge width to 10 μm, with a 5 μm EC-treated width, that reduced the current steering effect and increased the light scattering effect on the nanoporous structure. The EC-treated GaN:Si nanoporous structure acted as a high light scattering structure and a current steering structure that has potential on the current confinement for vertical cavity surface emitting laser applications. - Highlights: • High resistivity nanoporous-GaN formed in InGaN LED through electrochemical process. • Branch-like nanoporous in 5 μm-width bridge structure can steer the injection current. • Nanoporous GaN acted as s light scattering and current steering structures in InGaN LED

  20. Autonomous Shepherding Behaviors of Multiple Target Steering Robots

    Directory of Open Access Journals (Sweden)

    Wonki Lee

    2017-11-01

    Full Text Available This paper presents a distributed coordination methodology for multi-robot systems, based on nearest-neighbor interactions. Among many interesting tasks that may be performed using swarm robots, we propose a biologically-inspired control law for a shepherding task, whereby a group of external agents drives another group of agents to a desired location. First, we generated sheep-like robots that act like a flock. We assume that each agent is capable of measuring the relative location and velocity to each of its neighbors within a limited sensing area. Then, we designed a control strategy for shepherd-like robots that have information regarding where to go and a steering ability to control the flock, according to the robots’ position relative to the flock. We define several independent behavior rules; each agent calculates to what extent it will move by summarizing each rule. The flocking sheep agents detect the steering agents and try to avoid them; this tendency leads to movement of the flock. Each steering agent only needs to focus on guiding the nearest flocking agent to the desired location. Without centralized coordination, multiple steering agents produce an arc formation to control the flock effectively. In addition, we propose a new rule for collecting behavior, whereby a scattered flock or multiple flocks are consolidated. From simulation results with multiple robots, we show that each robot performs actions for the shepherding behavior, and only a few steering agents are needed to control the whole flock. The results are displayed in maps that trace the paths of the flock and steering robots. Performance is evaluated via time cost and path accuracy to demonstrate the effectiveness of this approach.

  1. Autonomous Shepherding Behaviors of Multiple Target Steering Robots.

    Science.gov (United States)

    Lee, Wonki; Kim, DaeEun

    2017-11-25

    This paper presents a distributed coordination methodology for multi-robot systems, based on nearest-neighbor interactions. Among many interesting tasks that may be performed using swarm robots, we propose a biologically-inspired control law for a shepherding task, whereby a group of external agents drives another group of agents to a desired location. First, we generated sheep-like robots that act like a flock. We assume that each agent is capable of measuring the relative location and velocity to each of its neighbors within a limited sensing area. Then, we designed a control strategy for shepherd-like robots that have information regarding where to go and a steering ability to control the flock, according to the robots' position relative to the flock. We define several independent behavior rules; each agent calculates to what extent it will move by summarizing each rule. The flocking sheep agents detect the steering agents and try to avoid them; this tendency leads to movement of the flock. Each steering agent only needs to focus on guiding the nearest flocking agent to the desired location. Without centralized coordination, multiple steering agents produce an arc formation to control the flock effectively. In addition, we propose a new rule for collecting behavior, whereby a scattered flock or multiple flocks are consolidated. From simulation results with multiple robots, we show that each robot performs actions for the shepherding behavior, and only a few steering agents are needed to control the whole flock. The results are displayed in maps that trace the paths of the flock and steering robots. Performance is evaluated via time cost and path accuracy to demonstrate the effectiveness of this approach.

  2. Stochastic stability of four-wheel-steering system

    International Nuclear Information System (INIS)

    Huang Dongwei; Wang Hongli; Zhu Zhiwen; Feng Zhang

    2007-01-01

    A four-wheel-steering system subjected to white noise excitations was reduced to a two-degree-of-freedom quasi-non-integrable-Hamiltonian system. Subsequently we obtained an one-dimensional Ito stochastic differential equation for the averaged Hamiltonian of the system by using the stochastic averaging method for quasi-non-integrable-Hamiltonian systems. Thus, the stochastic stability of four-wheel-steering system was analyzed by analyzing the sample behaviors of the averaged Hamiltonian at the boundary H = 0 and calculating its Lyapunov exponent. An example given at the end demonstrated that the conclusion obtained is of considerable significance

  3. Steering of Educational Processes in a Digital Medium Environment

    DEFF Research Database (Denmark)

    Tække, Jesper; Paulsen, Michael

    2015-01-01

    by systems theory we outline a more adequate way of teaching in the new medium environment – a teaching that can manage the new situation and use the new possibilities provided by the digital media. The argumentation builds on empirical findings from the action research project Socio Media Education (SME......This paper is about challenges to steering and leadership of educational interaction in classrooms provided by the new medium environment that comes with digital media. In the new medium environment, the old way of steering what is going on in the classroom appears not to work since...

  4. Balloon-Occluded Antegrade Transvenous Sclerotherapy to Treat Rectal Varices: A Direct Puncture Approach to the Superior Rectal Vein Through the Greater Sciatic Foramen Under CT Fluoroscopy Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Yasuyuki, E-mail: onoyasy@hirakata.kmu.ac.jp; Kariya, Shuji, E-mail: kariyas@hirakata.kmu.ac.jp; Nakatani, Miyuki, E-mail: nakatanm@hirakata.kmu.ac.jp; Yoshida, Rie, E-mail: yagir@hirakata.kmu.ac.jp; Kono, Yumiko, E-mail: kohnoy@hirakata.kmu.ac.jp; Kan, Naoki, E-mail: kanna@takii.kmu.ac.jp; Ueno, Yutaka, E-mail: uenoyut@hirakata.kmu.ac.jp; Komemushi, Atsushi, E-mail: komemush@takii.kmu.ac.jp; Tanigawa, Noboru, E-mail: tanigano@hirakata.kmu.ac.jp [Kansai Medical University, Department of Radiology (Japan)

    2015-10-15

    Rectal varices occur in 44.5 % of patients with ectopic varices caused by portal hypertension, and 48.6 % of these patients are untreated and followed by observation. However, bleeding occurs in 38 % and shock leading to death in 5 % of such patients. Two patients, an 80-year-old woman undergoing treatment for primary biliary cirrhosis (Child-Pugh class A) and a 63-year-old man with class C hepatic cirrhosis (Child-Pugh class A), in whom balloon-occluded antegrade transvenous sclerotherapy was performed to treat rectal varices are reported. A catheter was inserted by directly puncturing the rectal vein percutaneously through the greater sciatic foramen under computed tomographic fluoroscopy guidance. In both cases, the rectal varices were successfully treated without any significant complications, with no bleeding from rectal varices after embolization.

  5. Provenance for Runtime Workflow Steering and Validation in Computational Seismology

    Science.gov (United States)

    Spinuso, A.; Krischer, L.; Krause, A.; Filgueira, R.; Magnoni, F.; Muraleedharan, V.; David, M.

    2014-12-01

    Provenance systems may be offered by modern workflow engines to collect metadata about the data transformations at runtime. If combined with effective visualisation and monitoring interfaces, these provenance recordings can speed up the validation process of an experiment, suggesting interactive or automated interventions with immediate effects on the lifecycle of a workflow run. For instance, in the field of computational seismology, if we consider research applications performing long lasting cross correlation analysis and high resolution simulations, the immediate notification of logical errors and the rapid access to intermediate results, can produce reactions which foster a more efficient progress of the research. These applications are often executed in secured and sophisticated HPC and HTC infrastructures, highlighting the need for a comprehensive framework that facilitates the extraction of fine grained provenance and the development of provenance aware components, leveraging the scalability characteristics of the adopted workflow engines, whose enactment can be mapped to different technologies (MPI, Storm clusters, etc). This work looks at the adoption of W3C-PROV concepts and data model within a user driven processing and validation framework for seismic data, supporting also computational and data management steering. Validation needs to balance automation with user intervention, considering the scientist as part of the archiving process. Therefore, the provenance data is enriched with community-specific metadata vocabularies and control messages, making an experiment reproducible and its description consistent with the community understandings. Moreover, it can contain user defined terms and annotations. The current implementation of the system is supported by the EU-Funded VERCE (http://verce.eu). It provides, as well as the provenance generation mechanisms, a prototypal browser-based user interface and a web API built on top of a NoSQL storage

  6. Feasibility and Safety of Vascular Closure Devices in an Antegrade Approach to Either the Common Femoral Artery or the Superficial Femoral Artery

    Energy Technology Data Exchange (ETDEWEB)

    Gutzeit, Andreas, E-mail: andreas.gutzeit@ksw.ch; Schie, Bram van, E-mail: Bram.vanschie@hotmail.com; Schoch, Eric, E-mail: eric.schoch@ksw.ch [Cantonal Hospital Winterthur, Department of Radiology (Switzerland); Hergan, Klaus, E-mail: k.hergan@salk.at [Paracelsus Medical University Salzburg, Department of Radiology (Austria); Graf, Nicole, E-mail: graf@biostatistics.ch; Binkert, Christoph A., E-mail: christoph.binkert@ksw.ch [Cantonal Hospital Winterthur, Department of Radiology (Switzerland)

    2012-10-15

    Introduction: The purpose of the present study was to analyze complications following antegrade puncture of the common femoral artery (CFA) and the superficial femoral artery (SFA) using vascular closure systems (VCS). Methods: A single-center, retrospective study was performed after obtaining approval from the institutional review board and informed consent from all patients. At our center, the CFA or SFA are used for arterial access. All patients were evaluated clinically on the same day. If there was any suspicion of an access site problem, Duplex ultrasound was performed. Results: Access location was the CFA in 50 patients and the SFA in 130 patients. The sheath size ranged from 4F to 10F. Two patients had to be excluded because of lack of follow-up. Successful hemostasis was achieved in 162 of 178 cases (91 %). The following complications were observed in 16 patients (8.9 %): 4 pseudoaneurysms (2.2 %), 11 hematomas (6.2 %), and 1 vascular occlusion (0.5 %). The two pseudoaneurysms healed spontaneously, in one case an ultrasound-guided thrombin injection was performed, and one aneurysm was compressed manually. No further medical therapy was needed for the hematomas. The one vascular occlusion was treated immediately with angioplasty using a contralateral approach. No significant difference was noted between the CFA and the SFA group with respect to complications (p = 1.000). Conclusions: The use of closure devices for an antegrade approach up to 10F is feasible and safe. No differences in low complication rates were observed between CFA and SFA.

  7. 46 CFR 58.25-55 - Overcurrent protection for steering-gear systems.

    Science.gov (United States)

    2010-10-01

    ...— (1) 300% and not more than 375% of the rated full-load current of one steering-gear motor for a direct-current motor; or (2) 175% and not more than 200% of the locked-rotor current of one steering-gear... steering-gear motor, nor a motor for a steering-gear control system, may be protected by an overload...

  8. Effects of slow-release urea on ruminal digesta characteristics and growth performance in beef steers

    DEFF Research Database (Denmark)

    Taylor-Edwards, C C; Hibbard, G; Kitts, S E

    2009-01-01

    Two experiments were conducted to evaluate the effects of slow urea (SRU) versus feed-grade urea on ruminal metabolite characteristics in steers and DMI, gain, and G:F in growing beef steers.......Two experiments were conducted to evaluate the effects of slow urea (SRU) versus feed-grade urea on ruminal metabolite characteristics in steers and DMI, gain, and G:F in growing beef steers....

  9. Fast and reliable control of steering mirrors with application to free-space communication

    KAUST Repository

    Ibrir, Salim

    2018-03-15

    After modeling a laser beam pointing system actuated by a piezo-electric fast steering mirror (FSM), an observer-based linear feedback controller is developed to correct the position of the laser spot communicated by the position sensing detector (PSD). The modeling and the control actions have been considered with and without the hysteresis effect induced by the piezoelectric actuators of the FSM. The design of the feedback is given through the solution of parametric matrix inequalities. It was found that the integral feedback design is very efficient in handling input and system uncertainty. The linearity of the observer-based feedback has facilitated both the real-time implementation of the control strategy and the proof of stability using dynamic-output feedbacks.

  10. supplementation of energy and/or protein to steers grazing summer ...

    African Journals Online (AJOL)

    Some aspects of the effect of supplementary energy and/or protein, strategically ptovided to steers on summer veld, were investi gated. 40 Friesland steers in the age ... was posed whether the strategic provision of energy and or protein to steers grazing .... Definitions and abbreviotions was determined after cooling for 24 h ...

  11. 46 CFR 131.505 - Steering gear, whistle, and means of communication.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Steering gear, whistle, and means of communication. 131... examine and test the steering gear, the whistle, and the means of communication between the pilothouse and... VESSELS OPERATIONS Tests, Drills, and Inspections § 131.505 Steering gear, whistle, and means of...

  12. Chromium supplementation enhances the acute phase response of steers to a lipopolysaccharide (LPS) challenge

    Science.gov (United States)

    The study examined the effect of chromium supplementation on the response of steers to an LPS challenge. Twenty crossbred steers (235±4 kg BW) received 0 ppb (Control; C) or 200 ppb chromium propionate (CHR) for 55 days. Steers were fitted with jugular catheters and rectal temperature (RT) recording...

  13. Enhancement of the acute phase response to lipopolysaccharide (LPS) challenge in steers supplemented with chromium

    Science.gov (United States)

    The study examined the effect of chromium supplementation on the response of steers to an LPS challenge. Twenty steers received a premix that added 0 (control) or 0.2 mg/kg of chromium (KemTRACE®brandChromiumProprionate 0.04%, Kemin Industries) to the total diet on a dry matter basis for 55 d. Steer...

  14. 46 CFR 130.140 - Steering on OSVs of 100 or more gross tons.

    Science.gov (United States)

    2010-10-01

    ... must have the following: (1) A main steering gear of adequate strength for, and capable of, steering... single hydraulic sump of the “cascading overflow” type with a centerline bulkhead open only at the top, if each half has enough capacity to operate the system. (7) Control of the main steering gear from...

  15. Threats and protection for electronically-steered array radars

    NARCIS (Netherlands)

    Janssen, J.P.B.; Monni, S.; Maas, A.P.M.; Vliet, F.E. van

    2008-01-01

    Front-end power overload protection is a vital issue in any electro-magnetic sensor. The issues around active electronically-steered arrays are more recent and pose new threats. Different categories of threats can damage the sensitive electronics in the phased-array radar, like hostile high power

  16. Steering Micro-Robotic Swarm by Dynamic Actuating Fields

    NARCIS (Netherlands)

    Chao, Q.; Yu, J; Dai, C.; Xu, T; Zhang, L.; Wang, C.C.; Jin, X.

    2016-01-01

    We present a general solution for steering microrobotic
    swarm by dynamic actuating fields. In our approach, the
    motion of micro-robots is controlled by changing the actuating
    direction of a field applied to them. The time-series sequence
    of actuating field’s directions can be

  17. 49 CFR 393.209 - Steering wheel systems.

    Science.gov (United States)

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS PARTS AND ACCESSORIES... ball-and-socket joints shall not be worn, faulty or repaired by welding. The steering gear box shall...

  18. DSP-based electric power assisted steering using BLDC motor

    Indian Academy of Sciences (India)

    In the higher level of control architecture, the vehicle speed controller works as an assistance level controller for the steering effort. In the lower level, the torque controller gives the effort level control. This has been realized by torque sensor and vehicle sensor interfaced in the DSP. For implementing in the system, ...

  19. Slow-release urea in supplement fed to beef steers

    Directory of Open Access Journals (Sweden)

    Ana Paula Gonçalves

    2015-02-01

    Full Text Available Replacing regular urea (RU by slow-release urea (SRU at two levels of non-protein nitrogen (NPN in concentrate, offered with low-quality roughage, was evaluated in beef steers on dry matter intake (DMI, ruminal fermentation parameters, plasma urea nitrogen (PUN, total tract apparent digestibility of diets and in situ degradability of nitrogen sources. Eight ruminally cannulated steers were allocated into two 4x4 Latin squares, totalizing four treatments: 40 NPN/0 SRU: 40% of concentrate crude protein (CP as NPN, resulting from 0% of SRU and 100% of RU; 40 NPN/50 SRU: 40% of concentrate CP as NPN, resulting from 50% of SRU and 50% of RU; 40 NPN/100 SRU: 40% of concentrate CP as NPN, resulting from 100% of SRU and 0% of RU; 80 NPN/100 SRU: 80% of concentrate CP as NPN, resulting from 100% of SRU and 0% of RU. Results showed that partial substitution of regular urea by slow-release urea did not alter dry matter intake, pattern of ruminal fermentation or plasma urea nitrogen concentrations and increased the total tract apparent digestibility of crude protein in steers diets. The increase in non-protein nitrogen content in crude protein of the concentrate could compromise feed intake and the efficiency of nutrient utilization in the steers fed complete diets based on low quality forage.

  20. Complex Education Systems: From Steering Change to Governance

    Science.gov (United States)

    Michel, Alain

    2016-01-01

    The theories and approaches of steering/monitoring a process of change within education systems have evolved over the last 20 years or so as a result of many factors such as globalisation and decentralisation, a faster pace of change, increasing expectations and demands from various stakeholders (parents, employers, teacher unions, etc.) and the…

  1. Multifunctional Converter Drive for Automotive Electric Power Steering Systems

    NARCIS (Netherlands)

    Hackner, T.J.

    2013-01-01

    In this thesis it is shown that in the case of an automotive electric power steering system, critical pulse power loads can be decoupled from the power net with a storage element and a multifunctional converter. A multifunctional converter system is proposed because it uses the motor drive system as

  2. Carcass mass gains of steers grazing star grass, with different ...

    African Journals Online (AJOL)

    Carcass mass gains of steers grazing dryland Cynodon aethiopicus cv. No. 2 Star grass pastures during the growing season were determined for each of 16 treatments comprising four levels of nitrogen fertilisation in combination with four overlapping sets of stocking rates. The treatments were repeated over four growing ...

  3. CLOSED FORM OF THE STEERED ELONGATED HERMITE-GAUSS WAVELETS

    NARCIS (Netherlands)

    Papari, Giuseppe; Campisi, Patrizio; Petkov, Nicolai

    2010-01-01

    We provide a closed form, both in the spatial and in the frequency domain, of a family of wavelets which arise from steering elongated Hermite-Gauss filters. These wavelets have interesting mathematical properties, as they form new dyadic families of eigenfunctions of the 2D Fourier transform, and

  4. Liquid Crystal Based Optical Phased Array for Steering Lasers

    Science.gov (United States)

    2009-10-01

    limitations, several beam steering technologies have been proposed and developed, such as DMD/DLP by Texas Instruments technology,9-11 grating light valve...1989) 11 J.B.Sampsell, “The Digital Micromirror Device”, 7th ICSS&A, Yokohama, Japan (1993) 12 D. M. Bloom, Proc. SPIE 3013, (1998) 13 W. Kulcke

  5. Auditory orientation in crickets: Pattern recognition controls reactive steering

    Science.gov (United States)

    Poulet, James F. A.; Hedwig, Berthold

    2005-10-01

    Many groups of insects are specialists in exploiting sensory cues to locate food resources or conspecifics. To achieve orientation, bees and ants analyze the polarization pattern of the sky, male moths orient along the females' odor plume, and cicadas, grasshoppers, and crickets use acoustic signals to locate singing conspecifics. In comparison with olfactory and visual orientation, where learning is involved, auditory processing underlying orientation in insects appears to be more hardwired and genetically determined. In each of these examples, however, orientation requires a recognition process identifying the crucial sensory pattern to interact with a localization process directing the animal's locomotor activity. Here, we characterize this interaction. Using a sensitive trackball system, we show that, during cricket auditory behavior, the recognition process that is tuned toward the species-specific song pattern controls the amplitude of auditory evoked steering responses. Females perform small reactive steering movements toward any sound patterns. Hearing the male's calling song increases the gain of auditory steering within 2-5 s, and the animals even steer toward nonattractive sound patterns inserted into the speciesspecific pattern. This gain control mechanism in the auditory-to-motor pathway allows crickets to pursue species-specific sound patterns temporarily corrupted by environmental factors and may reflect the organization of recognition and localization networks in insects. localization | phonotaxis

  6. Image Processing In Laser-Beam-Steering Subsystem

    Science.gov (United States)

    Lesh, James R.; Ansari, Homayoon; Chen, Chien-Chung; Russell, Donald W.

    1996-01-01

    Conceptual design of image-processing circuitry developed for proposed tracking apparatus described in "Beam-Steering Subsystem For Laser Communication" (NPO-19069). In proposed system, desired frame rate achieved by "windowed" readout scheme in which only pixels containing and surrounding two spots read out and others skipped without being read. Image data processed rapidly and efficiently to achieve high frequency response.

  7. Steering characteristic of an articulated bus under quasi steady maneuvering

    Science.gov (United States)

    Ubaidillah, Setiawan, Budi Agus; Aridharma, Airlangga Putra; Lenggana, Bhre Wangsa; Caesar, Bernardus Placenta Previo

    2018-02-01

    Articulated buses have been being preferred as public transportation modes due to their operational capacity. Therefore, passenger safety must be the priority of this public service vehicle. This research focused on the analytical approach of steering characteristics of an articulated bus when it maneuvered steadily. Such turning condition could be referred as a stability parameter of the bus for preliminary handling assessment. The analytical approach employed kinematics relationship between front and rear bodies as well as steering capabilities. The quasi steady model was developed to determine steering parameters such as turning radius, oversteer, and understeer. The mathematical model was useful for determining both coefficients of understeer and oversteer. The dimension of articulated bus followed a commonly used bus as utilized in Trans Jakarta busses. Based on the simulation, for one minimum center of the body, the turning radius was calculated about 8.8 m and 7.6 m at steady turning speed of 10 km/h. In neutral condition, the minimum road radius should be 6.5 m at 10 km/h and 6.9 m at 40 km/h. For two centers of the body and oversteer condition, the front body has the turning radius of 8.8 m, while, the rear body has the turning radius of 9.8 m at both turning speeds of 40 km/h. The other steering parameters were discussed accordingly.

  8. Steroid implants and markers of bone turnover in steers | Knetter ...

    African Journals Online (AJOL)

    Thirty-two crossbred yearling steers were given one of four treatments to determine whether these markers of bone turnover could be detected and reflect steroid-induced bone maturity in the periphery: non-implanted controls; 25.7 mg estradiol-17β (E2); 120 mg trenbolone acetate (TBA); or 120 mg TBA and 24 mg E2 (T+E) ...

  9. Minutes: ANSI Steering Committee on Solar Energy Standards Development

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-04-29

    Minutes of the April 29, 1980, meeting of the American National Standards Institute steering committee on solar energy standards development are given. Attachments include correspondence from individuals and organizations which primarily describe the Solar Public Interest Coordination Committee (SPICC) and its recent activities. Also a report on the meeting of the ANSI subcommittee on international activity is attached. (WHK)

  10. Interagency Advanced Power Group -- Steering group meeting minutes

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-18

    This document contains the draft meeting minutes of the Steering Group of the Interagency Advanced Power Group. Included are the discussions resulting from the presentation of working group reports and the results of a discussion of IAPG policies and procedures. In the appendix are the reports of the following working groups: Electrical, Mechanical, Solar, and Systems.

  11. The Analysis of The Fault of Electrical Power Steering

    Directory of Open Access Journals (Sweden)

    Zhang Li Wen

    2016-01-01

    Full Text Available This paper analysis the common fault types of primary Electrical Power Steering system, meanwhile classify every fault. It provides the basis for further troubleshooting and maintenance. At the same time this paper propose a practical working principle of fault-tolerant, in order to make the EPS system more security and durability.

  12. Seasonal Variation in Carcass Characteristics of Korean Cattle Steers

    Directory of Open Access Journals (Sweden)

    M. Y. Piao

    2015-03-01

    Full Text Available Climate temperature affects animal production. This study was conducted to evaluate whether climatic conditions affect beef carcass characteristics of Korean cattle steers. The monthly carcass characteristics of Korean cattle steers (n = 2,182,415 for 8 yr (2006 through 2013 were collected from the Korean Institute for Animal Products Quality Evaluation. Daily climate temperature (CT and relative humidity (RH data were collected from the Korean Meteorological Administration. Weather conditions in South Korea during summer were hot and humid, with a maximum temperature of 28.4°C and a maximum RH of 91.4%. The temperature-humidity index (THI, calculated based on CT and RH, ranges from 73 to 80 during summer. Winter in South Korea was cold, with a minimum temperature of −4.0°C and a wind-chill temperature of −6.2°C. Both marbling score (MS and quality grade (QG of Korean cattle steer carcasses were generally best (p0.05 with CT. Yield grade (YG of Korean cattle steer carcasses was lowest (p<0.05 in winter (November to January and highest in spring and summer (May to September. A correlation analysis revealed that YG frequency was strongly correlated (r≥0.71; p<0.01 with CT and THI values. The rib eye area, a positive YG parameter, was not associated with CT. Backfat thickness (BT, a negative YG factor, was highest in winter (November and December. The BT was strongly negatively correlated (r≤−0.74; p<0.01 with CTs. Therefore, the poor YG during winter is likely due in part to the high BT. In conclusion, YG in Korean cattle steer carcasses was worst in winter. QGs were not associated with winter or summer climatic conditions.

  13. The Impact of Analog and Bang-Bang Steering Gear Control on Ship's Fuel Economy

    DEFF Research Database (Denmark)

    Nørtoft Thomsen, J. C.; Blanke, Mogens; Reid, R. E.

    1982-01-01

    system performance is evaluated from direct measurements of speed and fuel consumption, and results from several ships are given. The results presented should enhance the ability of ship owners and steering gear manufacturers to choose and design systems, which will minimize steering generated propulsion...... it is found to be at least equally important regarding steering performance and fuel economy. The paper presents a comprehensive survey of steering gear principles commonly used, including relevant details of three analog steering gear servo principles, which have outperformed conventional designs. Control...

  14. Study on a New Steering Mechanism for Point-the-Bit Rotary Steerable System

    Directory of Open Access Journals (Sweden)

    Yuanzhi Li

    2014-02-01

    Full Text Available This paper presents a novel steering mechanism embedded in a point-the-bit rotary steerable system (RSS for oilfield exploitation. The new steering mechanism adopts a set of universal joints to alleviate the high alternative strain on drilling mandrel and employs a specially designed planetary gear small tooth number difference (PGSTD to achieve directional steering. Its principle and characteristics are explained and examined through a series of analyses. First, the eccentric displacement vector of the offset point on the drilling mandrel is formulated and kinematic solutions are established. Next, structural design for the new steering mechanism is addressed. Then, procedures and program architectures for simulating offset state of the drilling mandrel and motion trajectory of the whole steering mechanism are presented. After that, steering motion simulations of the new steering mechanism for both 2D and 3D well trajectories are then performed by combining LabVIEW and SolidWorks. Finally, experiments on the steering motion control of the new steering mechanism prototype are carried out. The simulations and experiments reveal that the steering performance of the new steering mechanism is satisfied. The research can provide good guidance for further research and engineering application of the point-the-bit RSS.

  15. Project calculation of the steering mechanism hydraulic servo control in motor vehicles

    Directory of Open Access Journals (Sweden)

    Zoran Đukan Majkić

    2013-10-01

    Full Text Available Hydraulic servo controls are designed to facilitate rotation in place without providing increased ppower to steering wheels. In the initial design phase, the dimensions required for control systems are usually obtained through the calculation of their load when wheels rotate in place, where the torque is calculated empirically. The starting point in the project calculation is thus to determine the hydraulic power steering torque torsional resistance which is then used to determine the maximum value of force i.e. the torque on the stering wheel. The calculation of the control system servo control consists of determining the basic parameters, the required pump capacity, the main dimensions of the hub and the  pipeline and the conditions for the stability of the system control mechanism. Introduction The aim of the calculation of the steering control system is to determine the basic parameters of its components which ensure the fulfilment of requirements of the control system. Calculations are performed in several stages with a simultaneous  detailed constructive analysis of the control system leading to the best variant. At each stage, design and control calculations of the hydraulic servo of the steering mechanism are performed. The design allows the computation to complete the selection of basic dimensions of the amplifer elements, starting from the approved scheme and the basic building loads of approximate values. Calculations control is carried out to clarify the structural solution and to obtain the output characteristics of the control amplifier which are applied in the  estimation of  potential properties of the structure. Project calculation Baseline data must be sufficiently reliable, ie. must correspond to the construction characteristics of the vehicle design and the control system as well as to service conditions..A proper deterimination of the torque calculation of torsional resistance in wheels is of utmost importance. Moment of

  16. Dynamic modeling and simulation of trailer with compliance steering system

    Directory of Open Access Journals (Sweden)

    Qingyun Wang

    2017-01-01

    Full Text Available Stability of a vehicle and tire wear is affected by the movement inference between the tractor and the trailer when the trailer is turning. Therefore, to solve the problem, Compliant Steering (CS system is used. The system makes the rear-wheel of the trailer steer. After establishing a dynamic model of the trailer and the CS system, the simulation result shows that the system has a smaller lateral force. This smaller force at the hinge point indicates movement inference is reduced and motion response is far better. Furthermore, this paper contains the analysis of the influence of the key parameters of CS system and the speed on the moving characteristics of the trailer.

  17. Steering and filtering white light with resonant waveguide gratings

    Science.gov (United States)

    Quaranta, Giorgio; Basset, Guillaume; Martin, Olivier J. F.; Gallinet, Benjamin

    2017-08-01

    A novel thin-film single-layer structure based on resonant waveguide gratings (RWGs) allows to engineer selective color filtering and steering of white light. The unit cell of the structure consists of two adjacent finite-length and cross-talking RWGs, where the former acts as in-coupler and the latter acts as out-coupler. The structure is made by only one nano-imprint lithography replication and one thin film layer deposition, making it fully compatible with up-scalable fabrication processes. We characterize a fabricated optical security element designed to work with the flash and the camera of a smartphone in off-axis light steering configuration, where the pattern is revealed only by placing the smartphone in the proper position. Widespread applications are foreseen in a variety of fields, such as multifocal or monochromatic lenses, solar cells, biosensors, security devices and seethrough optical combiners for near-eye displays.

  18. Terrestrial Steering Group. 2014. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Aastrup, Peter; Aronsson, Mora; Barry, Tom

    implementation of the Arctic Terrestrial Biodiversity Monitoring Plan for the next two years. Identify expert networks required for successful implementation of the plan. Identify key gaps and opportunities for the TSG related to plan implementation and identify near-term next steps to address gaps.......The Terrestrial Steering Group (TSG), has initiated the implementation phase of the CBMP Terrestrial Plan. The CBMP Terrestrial Steering Group, along with a set of invited experts (see Appendix A for a participants list), met in Iceland from February 25-27th to develop a three year work plan...... to guide implementation of the CBMP-Terrestrial Plan. This report describes the outcome of that workshop. The aim of the workshop was to develop a three year work plan to guide implementation of the CBMP-Terrestrial Plan. The participants were tasked with devising an approach to both (a) determine what...

  19. Steering the dynamics within reduced space through quantum learning control

    International Nuclear Information System (INIS)

    Kim, Young Sik

    2003-01-01

    In quantum dynamics of many-body systems, to identify the Hamiltonian becomes more difficult very rapidly as the number of degrees of freedom increases. In order to simplify the dynamics and to deduce dynamically relevant Hamiltonian information, it is desirable to control the dynamics to lie within a reduced space. With a judicious choice for the cost functional, the closed loop optimal control experiments can be manipulated efficiently to steer the dynamics to lie within a subspace of the system eigenstates without requiring any prior detailed knowledge about the system Hamiltonian. The procedure is simulated for optimally controlled population transfer experiments in the system of two degrees of freedom. To show the feasibility of steering the dynamics to lie in a specified subspace, the learning algorithms guiding the dynamics are presented along with frequency filtering. The results demonstrate that the optimal control fields derive the system to the desired target state through the desired subspace

  20. EFFECT OF POULTRY MEAL ON THE PERFORMANCE OF FEEDLOT STEERS

    Directory of Open Access Journals (Sweden)

    A. Cabrera-Nuñez

    2014-08-01

    Full Text Available The aim of this study was to evaluate the effect of poultry meal on weight gain and carcass yield, under a housing system. 30 Swiss x Zebu steers were used, with an approximate weight of 353 kg, which were assigned under a completely randomized design in three treatments. T1 (control concentrate without poultry meal; T2 concentrate + 30% poultry meal and T3 concentrate + 35% poultry meal. The composition of the concentrate was based on ground sorghum, maize grain, wheat bran, ground mineral salt bale with 18% crude protein and 70% TDN. A significant effect (p ≤ 0.05 on the percentage of carcass weight of 53.0 was observed; 59.5 and 58.8% for T1, T2 and T3, respectively. The results indicate that supplementation based poultry meal 35% promoted greater yield in feedlot steers.

  1. Human sperm steer with second harmonics of the flagellar beat.

    Science.gov (United States)

    Saggiorato, Guglielmo; Alvarez, Luis; Jikeli, Jan F; Kaupp, U Benjamin; Gompper, Gerhard; Elgeti, Jens

    2017-11-10

    Sperm are propelled by bending waves traveling along their flagellum. For steering in gradients of sensory cues, sperm adjust the flagellar waveform. Symmetric and asymmetric waveforms result in straight and curved swimming paths, respectively. Two mechanisms causing spatially asymmetric waveforms have been proposed: an average flagellar curvature and buckling. We image flagella of human sperm tethered with the head to a surface. The waveform is characterized by a fundamental beat frequency and its second harmonic. The superposition of harmonics breaks the beat symmetry temporally rather than spatially. As a result, sperm rotate around the tethering point. The rotation velocity is determined by the second-harmonic amplitude and phase. Stimulation with the female sex hormone progesterone enhances the second-harmonic contribution and, thereby, modulates sperm rotation. Higher beat frequency components exist in other flagellated cells; therefore, this steering mechanism might be widespread and could inspire the design of synthetic microswimmers.

  2. Arrayed beam steering device for advanced 3D displays

    Science.gov (United States)

    Bae, Jungmok; Choi, Yoon-Sun; Choi, Kyuhwan; Kim, Yunhee; Kwon, Yongjoo; Song, Hoon; Kim, Eoksu; Choi, Seungyeol; Lee, Junghoon; Lee, Sangyoon

    2013-03-01

    An arrayed beam steering device enables much simplified system architectures for high quality multiview 3D displays by adapting time multiplexing and eye tracking scheme. An array device consisting of microscale liquid prisms is presented, where the prism surface between two immiscible liquids is electrically controlled to steer light beams by the principle of electrowetting. An array prototype with 280×280μm pixels was fabricated and demonstrated of its full optical performances. The maximum tilting angle of each prism was measured to be 22.5° in average, with a tracking resolution of less than 0.04°. In this paper, we report a design and fabrication of eletrowetting based prism array, opto-fluidic simulations, optical characterizations, as well as applications to achieve low fatigue 3D displays.

  3. Coherent optical monolithic phased-array antenna steering system

    Science.gov (United States)

    Hietala, Vincent M.; Kravitz, Stanley H.; Vawter, Gregory A.

    1994-01-01

    An optical-based RF beam steering system for phased-array antennas comprising a photonic integrated circuit (PIC). The system is based on optical heterodyning employed to produce microwave phase shifting by a monolithic PIC constructed entirely of passive components. Microwave power and control signal distribution to the antenna is accomplished by optical fiber, permitting physical separation of the PIC and its control functions from the antenna. The system reduces size, weight, complexity, and cost of phased-array antenna systems.

  4. X-ray tube with magnetic electron steering

    Science.gov (United States)

    Reed, Kim W.; Turman, Bobby N.; Kaye, Ronald J.; Schneider, Larry X.

    2000-01-01

    An X-ray tube uses a magnetic field to steer electrons. The magnetic field urges electrons toward the anode, increasing the proportion of electrons emitted from the cathode that reach desired portions of the anode and consequently contribute to X-ray production. The magnetic field also urges electrons reflected from the anode back to the anode, further increasing the efficiency of the tube.

  5. Workshop on automated beam steering and shaping (ABS). Proceedings

    International Nuclear Information System (INIS)

    Lindroos, M.

    1999-01-01

    A workshop on Automated Beam Steering and Shaping (ABS) was held at CERN in December 1998. This was the first workshop dedicated to this subject. The workshop had two major goals: to review the present status of ABS algorithms and systems around the world and to create a worldwide ABS community. These proceedings contain summary reports from all sessions, contributions from several presentations held at the workshop, and a complete set of abstracts for all presentations. (orig.)

  6. and alkali treatment of maize intake and utilization by steers

    African Journals Online (AJOL)

    AND ALKALI TREATMENT OF MAIZE. INTAKE AND UTILIZATION BY STEERS. Receipt of M.S. I6-02- 1982. II.H. N{eissner, L.H.P. Liebenberg*, J.P. Pienaar,. A.B" van Zyl and Brenda Botha. (Key words: grain wpplement, hay ir"ttoke, perJrtrmance). (Sleutelwoorde: graansuppIcmen t. ltoc;i-inname, prestasie). OPSOMMING.

  7. Optimization of steering elements in the RIA driver linac

    International Nuclear Information System (INIS)

    Lessner, E. S.; Aseev, V. S.; Ostroumov, P. N.; Physics

    2005-01-01

    The driver linac of the projected RIA facility is a versatile accelerator, a 1.4-GV, CW superconducting (SC) linac designed to simultaneously accelerate several heavy-ion charge states, providing beams from proton to uranium at 400 MeV/u at power levels at a minimum of 100 kW and up to 400 kW for most beams. Acceleration of multiple-charge-state uranium beams places stringent requirements on the linac design. A steering algorithm was derived that fulfilled the driver's real estate requirements, such as placement of steering dipole coils on SC solenoids and of beam position monitors outside cryostats, and beam-dynamics requirements, such as coupling effects induced by the focusing solenoids. The algorithm has been fully integrated into the tracking code TRACK and it is used to study and optimize the number and position of steering elements that minimize the multiple-beam centroid oscillations and preserve the beam emittance under misalignments of accelerating and transverse focusing elements in the driver linac

  8. Einstein-Podolsky-Rosen steering: Its geometric quantification and witness

    Science.gov (United States)

    Ku, Huan-Yu; Chen, Shin-Liang; Budroni, Costantino; Miranowicz, Adam; Chen, Yueh-Nan; Nori, Franco

    2018-02-01

    We propose a measure of quantum steerability, namely, a convex steering monotone, based on the trace distance between a given assemblage and its corresponding closest assemblage admitting a local-hidden-state (LHS) model. We provide methods to estimate such a quantity, via lower and upper bounds, based on semidefinite programming. One of these upper bounds has a clear geometrical interpretation as a linear function of rescaled Euclidean distances in the Bloch sphere between the normalized quantum states of (i) a given assemblage and (ii) an LHS assemblage. For a qubit-qubit quantum state, these ideas also allow us to visualize various steerability properties of the state in the Bloch sphere via the so-called LHS surface. In particular, some steerability properties can be obtained by comparing such an LHS surface with a corresponding quantum steering ellipsoid. Thus, we propose a witness of steerability corresponding to the difference of the volumes enclosed by these two surfaces. This witness (which reveals the steerability of a quantum state) enables one to find an optimal measurement basis, which can then be used to determine the proposed steering monotone (which describes the steerability of an assemblage) optimized over all mutually unbiased bases.

  9. Development of Estimation Force Feedback Torque Control Algorithm for Driver Steering Feel in Vehicle Steer by Wire System: Hardware in the Loop

    Directory of Open Access Journals (Sweden)

    Sheikh Muhammad Hafiz Fahami

    2015-01-01

    Full Text Available In conventional steering system, a feedback torque is produced from the contact between tire and road surface and its flows through mechanical column shaft directly to driver. This allows the driver to sense the steering feel during driving. However, in steer by wire (SBW system, the elimination of the mechanical column shaft requires the system to generate the feedback torque which should produce similar performance with conventional steering system. Therefore, this paper proposes a control algorithm to create the force feedback torque for SBW system. The direct current measurement approach is used to estimate torque at the steering wheel and front axle motor as elements to the feedback torque, while, adding the compensation torque for a realistic feedback torque. The gain scheduling with a linear quadratic regulator controller is used to control the feedback torque and to vary a steering feel gain. To investigate the effectiveness of the proposed algorithm, a real-time hardware in the loop (HIL methodology is developed using Matlab XPC target toolbox. The results show that the proposed algorithm is able to generate the feedback torque similar to EPS steering system. Furthermore, the compensation torque is able to improve the steering feel and stabilize the system.

  10. A study of relative horn fly, Haematobia irritans (Diptera: Muscidae), abundance on Holstein steers and steers of two Holstein crosses.

    Science.gov (United States)

    Guglielmone, A A; Volpogni, M M; Castro, H; Mangold, A J; Anziani, O S

    2002-10-16

    A study was performed to determine if the number of horn fly (Haematobia irritans) adults differ significantly on Holstein (black and white coat color), Holstein x Holstein Friesian (black and white coat color) and Holstein x Jersey (black coat color) steers, 10-12 months old at the onset of the study. All steers were run together on lucerne paddocks and the number of flies counted at 30-day intervals from September 2000 to August 2001. No significant differences (P > 0.05, test of Kruskal-Wallis) were found in fly numbers, even in the period April-May 2001 when the infestation reached its peak. We were unable to demonstrate that coat color influenced horn fly abundance in the present study. It appears that none of the biotypes evaluated had any advantage for natural control of H. irritans.

  11. Analysis of Roll Steering for Solar Electric Propulsion Missions

    Science.gov (United States)

    Pederson, Dylan, M.; Hojnicki, Jeffrey, S.

    2012-01-01

    Nothing is more vital to a spacecraft than power. Solar Electric Propulsion (SEP) uses that power to provide a safe, reliable, and, most importantly, fuel efficient means to propel a spacecraft to its destination. The power performance of an SEP vehicle s solar arrays and electrical power system (EPS) is largely influenced by the environment in which the spacecraft is operating. One of the most important factors that determines solar array power performance is how directly the arrays are pointed to the sun. To get the most power from the solar arrays, the obvious solution is to point them directly at the sun at all times. Doing so is not a problem in deep space, as the environment and pointing conditions that a spacecraft faces are fairly constant and are easy to accommodate, if necessary. However, large and sometimes rapid variations in environmental and pointing conditions are experienced by Earth orbiting spacecraft. SEP spacecraft also have the additional constraint of needing to keep the thrust vector aligned with the velocity vector. Thus, it is important to analyze solar array power performance for any vehicle that spends an extended amount of time orbiting the Earth, and to determine how much off-pointing can be tolerated to produce the required power for a given spacecraft. This paper documents the benefits and drawbacks of perfectly pointing the solar arrays of an SEP spacecraft spiraling from Earth orbit, and how this might be accomplished. Benefits and drawbacks are defined in terms of vehicle mass, power, volume, complexity, and cost. This paper will also look at the application of various solar array pointing methods to future missions. One such pointing method of interest is called roll steering . Roll steering involves rolling the entire vehicle twice each orbit. Roll steering, combined with solar array gimbal tracking, is used to point the solar arrays perfectly towards the sun at all points in the orbit, while keeping the vehicle thrusters aligned

  12. Data transfer through beam steering using agile lensing

    Science.gov (United States)

    Arshad, Muhammad Assad; Reza, Syed Azer; Muhammad, Ahsan

    2016-04-01

    This paper presents a data transfer scheme using multi-focus tunable lenses. The design involves the use of a standard laser source and a variable focus agile lens to steer to the laser beam that passes through the lens. In our proposed system, the beam steer angle depends on an input electrical signal which drives the tunable lens. Therefore the beam steer angle is made to follow the variations in the input electrical drive signal. This is extremely interesting for data transfer applications as the data signal can be used as the input drive signal to the lens. The laser beam is steered according to the input data voltage levels and when the beam is incident on a photo-detector of a finite size, only a fraction of its total incident optical power is received by the photo-detector. This power contribution is proportional to the fraction of the total number of photons per unit area which are incident on the active area of the detector. The remaining photons which are not incident on the photo-detector do not contribute to the received power at the photo-detector. We present the theory of beam steering through a tunable lens and present a theoretical framework which governs data transfer through the proposed method. We also present the transfer function of the proposed system which helps us to calculate its essential theoretical performance parameters such as modulation depth and bit error rates. We also present experimental results to demonstrate efficient data transfer through the proposed method. As tunable lenses are primarily deployed in motion-free multi-focus cameras hence most of the modern portable devices such as cellphones and tablets use these lenses to operate the in-built variable focus cameras that are part of these devices. Because tunable lenses are commonly present in several different portable devices, the proposed method of data transfer between two devices is highly promising as it expands the use of the already deployed tunable lenses with

  13. An investigation on motor-driven power steering-based crosswind disturbance compensation for the reduction of driver steering effort

    Science.gov (United States)

    Kim, Kyuwon; Kim, Boemjun; Go, Youngil; Park, Jaeyong; Park, Joonhong; Suh, Insoo; Yi, Kyongsu

    2014-07-01

    This paper describes a lateral disturbance compensation algorithm for an application to a motor-driven power steering (MDPS)-based driver assistant system. The lateral disturbance including wind force and lateral load transfer by bank angle reduces the driver's steering refinement and at the same time increases the possibility of an accident. A lateral disturbance compensation algorithm is designed to determine the motor overlay torque of an MDPS system for reducing the manoeuvreing effort of a human driver under lateral disturbance. Motor overlay torque for the compensation of driver's steering torque induced by the lateral disturbance consists of human torque feedback and feedforward torque. Vehicle-driver system dynamics have been investigated using a combined dynamic model which consists of a vehicle dynamic model, driver steering dynamic model and lateral disturbance model. The human torque feedback input has been designed via the investigation of the vehicle-driver system dynamics. Feedforward input torque is calculated to compensate additional tyre self-aligning torque from an estimated lateral disturbance. The proposed compensation algorithm has been implemented on a developed driver model which represents the driver's manoeuvreing characteristics under the lateral disturbance. The developed driver model has been validated with test data via a driving simulator in a crosswind condition. Human-in-the-loop simulations with a full-scale driving simulator on a virtual test track have been conducted to investigate the real-time performance of the proposed lateral disturbance compensation algorithm. It has been shown from simulation studies and human-in-the-loop simulation results that the driver's manoeuvreing effort and a lateral deviation of the vehicle under the lateral disturbance can be significantly reduced via the lateral disturbance compensation algorithm.

  14. GEOMETRIC ANALYSIS OF MANEUVERABILITY PERFORMANCE FOR VEHICLES WITH TWO STEERING AXLES

    Directory of Open Access Journals (Sweden)

    Jędrzej PILISIEWICZ

    2017-06-01

    Full Text Available One of the most important features of motor vehicles is their steering maneuverability. Ways of determining single axle steering are well known. This paper presents an idea of how to determine maneuverability of motor vehicles with two steering axles. The concept makes use of elements of kinematic analysis as well as of a 3D model of the steering system. It is based on the theoretical analysis of the most unfavorable situations, such as parallel and perpendicular parking techniques, on the basis of which wheel-steering angles are specified. As a result, it was possible to create a 3D model to simulate the actual operation of the steering system. This made it possible to compare the theoretical approach with the actual system design.

  15. Integrated Design and Analysis Tools for Reduced Weight, Affordable Fiber Steered Composites

    National Research Council Canada - National Science Library

    Hale, Richard

    2004-01-01

    This report describes geometric design tools which encompass the overall process flow for fiber placed and fiber steered structures, to allow parallel considerations for manufacturability and mechanical performance...

  16. Modeling, Validation, and Control of Electronically Actuated Pitman Arm Steering for Armored Vehicle

    Directory of Open Access Journals (Sweden)

    Vimal Rau Aparow

    2016-01-01

    Full Text Available In this study, 2 DOF mathematical models of Pitman arm steering system are derived using Newton’s law of motion and modeled in MATLAB/SIMULINK software. The developed steering model is included with a DC motor model which is directly attached to the steering column. The Pitman arm steering model is then validated with actual Pitman arm steering test rig using various lateral inputs such as double lane change, step steer, and slalom test. Meanwhile, a position tracking control method has been used in order to evaluate the effectiveness of the validated model to be implemented in active safety system of a heavy vehicle. The similar method has been used to test the actual Pitman arm steering mechanism using hardware-in-the-loop simulation (HILS technique. Additional friction compensation is added in the HILS technique in order to minimize the frictional effects that occur in the mechanical configuration of the DC motor and Pitman arm steering. The performance of the electronically actuated Pitman arm steering system can be used to develop a firing-on-the-move actuator (FOMA for an armored vehicle. The FOMA can be used as an active safety system to reject unwanted yaw motion due to the firing force.

  17. Visual explorer facilitator's guide

    CERN Document Server

    Palus, Charles J

    2010-01-01

    Grounded in research and practice, the Visual Explorer™ Facilitator's Guide provides a method for supporting collaborative, creative conversations about complex issues through the power of images. The guide is available as a component in the Visual Explorer Facilitator's Letter-sized Set, Visual Explorer Facilitator's Post card-sized Set, Visual Explorer Playing Card-sized Set, and is also available as a stand-alone title for purchase to assist multiple tool users in an organization.

  18. : Light Steering Projection Systems and Attributes for HDR Displays

    KAUST Repository

    Damberg, Gerwin

    2017-06-02

    New light steering projectors in cinema form images by moving light away from dark regions into bright areas of an image. In these systems, the peak luminance of small features can far exceed full screen white luminance. In traditional projectors where light is filtered or blocked in order to give shades of gray (or colors), the peak luminance is fixed. The luminance of chromatic features benefit in the same way as white features, and chromatic image details can be reproduced at high brightness leading to a much wider overall color gamut coverage than previously possible. Projectors of this capability are desired by the creative community to aid in and enhance storytelling. Furthermore, reduced light source power requirements of light steering projectors provide additional economic and environmental benefits. While the dependency of peak luminance level on (bright) image feature size is new in the digital cinema space, display technologies with identical characteristics such as OLED, LED LCD and Plasma TVs are well established in the home. Similarly, direct view LED walls are popular in events, advertising and architectural markets. To enable consistent color reproduction across devices in today’s content production pipelines, models that describe modern projectors and display attributes need to evolve together with HDR standards and available metadata. This paper is a first step towards rethinking legacy display descriptors such as contrast, peak luminance and color primaries in light of new display technology. We first summarize recent progress in the field of light steering projectors in cinema and then, based on new projector and existing display characteristics propose the inclusion of two simple display attributes: Maximum Average Luminance and Peak (Color) Primary Luminance. We show that the proposed attributes allow a better prediction of content reproducibility on HDR displays. To validate this assertion, we test professional content on a commercial HDR

  19. Constrained Laboratory vs. Unconstrained Steering-Induced Rollover Crash Tests.

    Science.gov (United States)

    Kerrigan, Jason R; Toczyski, Jacek; Roberts, Carolyn; Zhang, Qi; Clauser, Mark

    2015-01-01

    The goal of this study was to evaluate how well an in-laboratory rollover crash test methodology that constrains vehicle motion can reproduce the dynamics of unconstrained full-scale steering-induced rollover crash tests in sand. Data from previously-published unconstrained steering-induced rollover crash tests using a full-size pickup and mid-sized sedan were analyzed to determine vehicle-to-ground impact conditions and kinematic response of the vehicles throughout the tests. Then, a pair of replicate vehicles were prepared to match the inertial properties of the steering-induced test vehicles and configured to record dynamic roof structure deformations and kinematic response. Both vehicles experienced greater increases in roll-axis angular velocities in the unconstrained tests than in the constrained tests; however, the increases that occurred during the trailing side roof interaction were nearly identical between tests for both vehicles. Both vehicles experienced linear accelerations in the constrained tests that were similar to those in the unconstrained tests, but the pickup, in particular, had accelerations that were matched in magnitude, timing, and duration very closely between the two test types. Deformations in the truck test were higher in the constrained than the unconstrained, and deformations in the sedan were greater in the unconstrained than the constrained as a result of constraints of the test fixture, and differences in impact velocity for the trailing side. The results of the current study suggest that in-laboratory rollover tests can be used to simulate the injury-causing portions of unconstrained rollover crashes. To date, such a demonstration has not yet been published in the open literature. This study did, however, show that road surface can affect vehicle response in a way that may not be able to be mimicked in the laboratory. Lastly, this study showed that configuring the in-laboratory tests to match the leading-side touchdown conditions

  20. Rumen microbiome from steers differing in feed efficiency.

    Directory of Open Access Journals (Sweden)

    Phillip R Myer

    Full Text Available The cattle rumen has a diverse microbial ecosystem that is essential for the host to digest plant material. Extremes in body weight (BW gain in mice and humans have been associated with different intestinal microbial populations. The objective of this study was to characterize the microbiome of the cattle rumen among steers differing in feed efficiency. Two contemporary groups of steers (n=148 and n=197 were fed a ration (dry matter basis of 57.35% dry-rolled corn, 30% wet distillers grain with solubles, 8% alfalfa hay, 4.25% supplement, and 0.4% urea for 63 days. Individual feed intake (FI and BW gain were determined. Within contemporary group, the four steers within each Cartesian quadrant were sampled (n=16/group from the bivariate distribution of average daily BW gain and average daily FI. Bacterial 16S rRNA gene amplicons were sequenced from the harvested bovine rumen fluid samples using next-generation sequencing technology. No significant changes in diversity or richness were indicated, and UniFrac principal coordinate analysis did not show any separation of microbial communities within the rumen. However, the abundances of relative microbial populations and operational taxonomic units did reveal significant differences with reference to feed efficiency groups. Bacteroidetes and Firmicutes were the dominant phyla in all ruminal groups, with significant population shifts in relevant ruminal taxa, including phyla Firmicutes and Lentisphaerae, as well as genera Succiniclasticum, Lactobacillus, Ruminococcus, and Prevotella. This study suggests the involvement of the rumen microbiome as a component influencing the efficiency of weight gain at the 16S level, which can be utilized to better understand variations in microbial ecology as well as host factors that will improve feed efficiency.

  1. Low-cost large-angle steering mirror development

    Science.gov (United States)

    Wassom, Steven R.

    2009-08-01

    The Space Dynamics Laboratory has combined internal funds with its background in space-rated mechanisms to develop a prototype low-cost large-angle 2-axis fine steering mirror (FSM). The FSM has a 75-mm clear aperture, 30-degree mechanical elevation angle, 120-degree mechanical azimuth angle, and a 70-Hertz small-amplitude bandwidth. Key components include a rotary voice coil, unique patent-pending feedback sensor, brushless DC motor and optical encoder. Average error is portable demonstration electronics development, and thermal-vacuum testing to pressures down to 1e-7 torr and temperatures down to 164 K.

  2. Adaptive feedback linearization applied to steering of ships

    Directory of Open Access Journals (Sweden)

    Thor I. Fossen

    1993-10-01

    Full Text Available This paper describes the application of feedback linearization to automatic steering of ships. The flexibility of the design procedure allows the autopilot to be optimized for both course-keeping and course-changing manoeuvres. Direct adaptive versions of both the course-keeping and turning controller are derived. The advantages of the adaptive controllers are improved performance and reduced fuel consumption. The application of nonlinear control theory also allows the designer in a systematic manner to compensate for nonlinearities in the control design.

  3. Concept of navigation and automatic steering of the measuring dolphin

    Energy Technology Data Exchange (ETDEWEB)

    Majohr, J.; Buch, T.; Korte, C. [Rostock Univ. (Germany). Inst. fuer Automatisierungstechnik

    2000-07-01

    The Catamaran - Measuring Dolphin (MESSIN) is an unmanned and independently operated craft having been designed for carrying out multiple measuring tasks in the field of marine research and water monitoring especially in shallow waters. An introduction to the navigation, steering and safety systems is given. Furthermore the main components of the track control system and the electronic chart system used here are shown. Results of manoeuvring tests of the MESSIN are represented. This paper gives a contribution to the field of research ''autonomous and full automated vehicle''. (orig.)

  4. A wireless capsule endoscopy steering mechanism using magnetic field platform.

    Science.gov (United States)

    Alsunaydih, Fahad N; Redoute, Jean-Michel; Yuce, Mehmet R

    2017-07-01

    In this paper, a new steering mechanism for wireless capsule devices is presented. The proposed system consists of a platform generating a magnetic field to direct and control the motion of a capsule. The platform contains an upper and a lower set of electromagnets. A permanent magnet is implanted inside the capsule to initiate the movement, which is set by the magnetic field delivered by the electromagnets. The total magnetic field at the capsule's location is the sum of the contributions of each electromagnet. An experimental setup has been designed for testing and comparing between the performance of the capsule mobility in practice and simulations.

  5. Training facilitators and supervisors

    DEFF Research Database (Denmark)

    Kjær, Louise Binow; O Connor, Maja; Krogh, Kristian

    At the Master’s program in Medicine at Aarhus University, Denmark, we have developed a faculty development program for facilitators and supervisors in 4 progressing student modules in communication, cooperation, and leadership. 1) A course for module 1 and 3 facilitators inspired by the apprentic...

  6. Trade Facilitation in Ethiopia:

    African Journals Online (AJOL)

    Tilahun_EK

    (UNCTAD), “Trade and transport facilitation … addresses a wide agenda in economic development and trade that may include improving transport infrastructure and services, reducing customs tariffs, and removing non-tariff trade barriers including administrative and regulatory barriers.”24. The definition of trade facilitation ...

  7. Learning facilitating leadership

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard; Hansen, Mette Sanne

    2016-01-01

    deployed for this paper is empirical and conceptual. A specific facilitation project carried out by six international engineering students is presented. The importance of combining cognitive, emotional and synergistic skills is highlighted on the basis of this example, the authors’ extensive experience......This paper explains how engineering students at a Danish university acquired the necessary skills to become emergent facilitators of organisational development. The implications of this approach are discussed and related to relevant viewpoints and findings in the literature. The methodology...... in teaching facilitation and the literature. These types of skills are most effectively acquired by combining conceptual lectures, classroom exercises and the facilitation of groups in a real-life context. The paper also reflects certain ‘shadow sides’ related to facilitation observed by the students...

  8. Towards human-controlled, real-time shape sensing based flexible needle steering for MRI-guided percutaneous therapies.

    Science.gov (United States)

    Li, Meng; Li, Gang; Gonenc, Berk; Duan, Xingguang; Iordachita, Iulian

    2017-06-01

    Accurate needle placement into soft tissue is essential to percutaneous prostate cancer diagnosis and treatment procedures. This paper discusses the steering of a 20 gauge (G) FBG-integrated needle with three sets of Fiber Bragg Grating (FBG) sensors. A fourth-order polynomial shape reconstruction method is introduced and compared with previous approaches. To control the needle, a bicycle model based navigation method is developed to provide visual guidance lines for clinicians. A real-time model updating method is proposed for needle steering inside inhomogeneous tissue. A series of experiments were performed to evaluate the proposed needle shape reconstruction, visual guidance and real-time model updating methods. Targeting experiments were performed in soft plastic phantoms and in vitro tissues with insertion depths ranging between 90 and 120 mm. Average targeting errors calculated based upon the acquired camera images were 0.40 ± 0.35 mm in homogeneous plastic phantoms, 0.61 ± 0.45 mm in multilayer plastic phantoms and 0.69 ± 0.25 mm in ex vivo tissue. Results endorse the feasibility and accuracy of the needle shape reconstruction and visual guidance methods developed in this work. The approach implemented for the multilayer phantom study could facilitate accurate needle placement efforts in real inhomogeneous tissues. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Shoulder function after surgical treatment of displaced fractures of the humeral shaft: a randomized trial comparing antegrade intramedullary nailing with minimally invasive plate osteosynthesis.

    Science.gov (United States)

    Benegas, Eduardo; Ferreira Neto, Arnaldo Amado; Gracitelli, Mauro Emilio Conforto; Malavolta, Eduardo Angeli; Assunção, Jorge Henrique; Prada, Flávia De Santis; Bolliger Neto, Raul; Mattar, Rames

    2014-06-01

    Minimally invasive plate osteosynthesis for humeral shaft fractures has been described recently, but there are no randomized studies comparing the clinical results for shoulder function between this technique and locking intramedullary nailing. A prospective randomized study was performed. Forty-one humeral shaft fractures (40 patients) were randomized to be treated with a minimally invasive plate (n = 21) or a locking intramedullary nail (n = 19). Clinical and radiographic outcome assessments were conducted at 1 year postoperatively. Shoulder function was the primary outcome, as measured by the University of California, Los Angeles Shoulder Scale. Elbow function was measured by the Broberg-Morrey score, and fracture consolidation and complications were the main secondary outcomes. At 1 year postoperatively, no significant difference was found with regard to shoulder function according to the University of California, Los Angeles scale between the minimally invasive plate and locking intramedullary nail (31.4 points vs 31.2 points, P = .98). There was also no difference in elbow function (94.8 points vs 94.1 points, P = .96). Complications were similar between the groups, without significant differences regarding infection (P > .99), symptomatic shoulder stiffness (P = .488), and neurapraxia of the lateral cutaneous nerve of the forearm (P = .475). Fracture union was achieved in all but 1 patient (2.4%) in the intramedullary nail group within 1 year after the surgical procedure. There is no significant difference in shoulder function between antegrade intramedullary nailing and minimally invasive plate osteosynthesis for the treatment of displaced humeral shaft fractures, despite the limited power of our study. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  10. Use of both antegrade and retrograde internal mammary vessels in the bipedicled deep inferior epigastric perforator flap for unilateral breast reconstruction.

    Science.gov (United States)

    Hernandez Rosa, Jonatan; Sherif, Rami D; Torina, Philip J; Harmaty, Marco A

    2017-01-01

    Autologous abdominal tissue transfer is a well-established method of breast reconstruction. The deep inferior epigastric perforator (DIEP) flap has the additional benefit of minimal donor site morbidity as it spares the muscle and fascia. Conventional DIEP flaps may not provide adequate volume in cases where the patient is thin, has midline abdominal scars, and/or has a large volume of tissue to replace. One solution is to use a bipedicled DIEP flap, incorporating all the available abdominal tissue. Bipedicled DIEP flaps have been described in a number of different configurations. The literature appears to favor intra-flap anastomosis, with a minimal exposition of two recipient vessels. It has been demonstrated that both the antegrade internal mammary artery (aIMA) and retrograde internal mammary artery (rIMA) are adequate recipient vessels. Here, the authors present a single-center experience with bipedicled DIEP flaps to both the aIMA and rIMA, showing their feasibility and safety. A retrospective review of patients who underwent unilateral breast reconstruction using bipedicled DIEP flaps was performed to assess outcomes. A total of 20 patients who underwent unilateral breast reconstruction using a bipedicled DIEP flap were selected for this study. All of them were previously diagnosed with cancer. There were zero flap failure and zero instance of abdominal hernia or issue with abdominal wall functionality following the surgeries. The series of surgeries described in this study resulted in successful breast reconstruction in 20 women using a bipedicled DIEP flap. The results show that this approach allows for reconstruction in places where a conventional DIEP does not provide adequate volume, achieved safely, and does not increase morbidity. The bipedicled DIEP flap is a viable option for large-volume autologous breast reconstruction, providing ample tissue for successful reconstruction while also allowing for shorter recovery and limited donor site morbidity

  11. The Malone Antegrade Continence Enema (MACE principle in children: is it important if the conduit is implanted in the left or the right colon?

    Directory of Open Access Journals (Sweden)

    Karine F. Meyer

    2008-03-01

    Full Text Available OBJECTIVE: The aim of the study was to determine which was the optimal side for the conduit to be placed (right or left colon for antegrade continence enema implantation. MATERIALS AND METHODS: Between July 1999 and March 2006, 31 patients underwent the construction of a catheterizable conduit using the Malone principle (MACE In 22 cases the conduit was re-implanted in the right colon and in 9 cases in the left colon. There were 20 male patients and 11 female patients, with a mean age of 10.23 years. The follow-up period varied from 3 from 83 months (average 25 months. Right and left implantation of the conduit in the colon were compared with regards to the presence of complications, volume of the solution utilized, frequency of colonic lavage, time needed for performing the enema, and degree of satisfaction. RESULTS: One patient with the conduit in the right colon, using the appendix, lost the mechanism after two month follow-up. Thirty patients remain clean and are all capable of performing self-catheterization. No statistically significant differences were found between the groups regarding the variables studied: complications (p = 1.000, solution volume (p = 0.996, time required (p = 0.790 and patient's rating (p = 0.670. The lavage frequency required for patients with the conduit in the right colon may be lower. CONCLUSION: The MACE principle was considered effective for treating fecal retention and leaks, independent of the implantation site. The success of this surgery appears to be directly related to the patient's motivation and not to the technique utilized.

  12. The steering committee for the marketing of radurised foods

    International Nuclear Information System (INIS)

    Wessels, P.J.

    1985-01-01

    After the very successful results obtained during the initial research stage of food irradiation, a need was felt for the commercial application of the process. Although few, if any, other food processing methods have been so thoroughly investigated prior to acceptance, several factors influenced the spontaneous implementation thereof. A definite need for co-ordination of commercial trials and proper commercial introduction of the process which invited so many discussions world-wide, led to the introduction of the Steering Committee for Radurised Foodstuffs in South Africa by the Minister of Agriculture during 1981. The Steering Committee was established to advise the Minister of Agriculture regarding the acceptability of the process and the progress made in this regard. The Minister of Agriculture (now Agricultural Economics and Water Affairs) fulfills an important role in the marketing of agricultural products in South Africa. Many decisions and recommendations of Organised Agriculture and of the different Marketing Boards are subject to the final approval or acceptance by the Minister. It is therefore important that he will be informed and advised regarding radurisation of foodstuffs and related aspects

  13. Stability Simulation of a Vehicle with Wheel Active Steering

    Directory of Open Access Journals (Sweden)

    Brabec Pavel

    2016-01-01

    Full Text Available This paper deals with the possibility of increasing the vehicle driving stability at a higher speed. One of the ways how to achieve higher stability is using the 4WS system. Mathematical description of vehicle general movement is a very complex task. For simulation, models which are aptly simplified are used. For the first approach, so-called single-truck vehicle model (often linear is usually used. For the simulation, we have chosen to extend the model into a two-truck one, which includes the possibility to input more vehicle parameters. Considering the 4WS system, it is possible to use a number of potential regulations. In our simulation model, the regulation system with compound coupling was used. This type of regulation turns the rear wheels depending on the input parameters of the system (steering angle of the front wheels and depending on the output moving quantities of the vehicle, most frequently the yaw rate. Criterion for compensation of lateral deflection centre of gravity angle is its zero value, or more precisely the zero value of its first-order derivative. Parameters and set-up of the simulation model were done in conjunction with the dSAPACE software. Reference performances of the vehicle simulation model were made through the defined manoeuvres. But the simulation results indicate that the rear-wheels steering can have a positive effect on the vehicle movement stability, especially when changing the driving direction at high speed.

  14. Reducing supplementation frequency for Nellore beef steers grazing tropical pastures

    Directory of Open Access Journals (Sweden)

    Roberta Carrilho Canesin

    2014-04-01

    Full Text Available Reduced supplementation frequency is a broadly applied management practice. Ruminants consuming low quality forages/pastures, supplemented less than once daily are able to maintain body weight gain (BWG, efficiency of use of dry matter, nitrogen and other nutrients, as compared with animals supplemented once daily. We evaluated the feeding behavior, dry matter intake (DMI, dry matter and organic matter digestibility (DMD and OMD, BWG, Longissimus muscle area and backfat depth of Nellore steers raised on Brachiaria brizantha cv. Marandu pastures during the dry season, with different supplementation patterns. Thirty six animals (338 ± 40.7 kg were distributed over nine paddocks according to a completely randomized design. Treatments were based on supplementation frequency: once daily (OD, once daily except Saturdays and Sundays (SS, or on alternate days (AD, at 1.0 %, 1.4 % and 2.0 % BW, respectively. Average total DMI accounted for 1.6 % BW day-1, with no effect of supplementation frequency. Supplementation frequency had no effect on BWG or grazing time during the day. There was no difference in Longissimus muscle area animals supplemented daily, SS and AD. The backfat depth was thinner in animals supplemented AD, but even in this case, it was within the standards considered satisfactory for a finishing steer. Reducing supplementation frequency seems a good option to lower labor costs without affecting feed efficiency or carcass quality in beef cattle grazing tropical pastures.

  15. Monitoring and Steering of Large-Scale Distributed Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Geist, G.A.; Kohl, J.A.

    1999-09-01

    Oak Ridge National Laboratory is developing a state-of-the-art parallel application development system called CUMULVS, which allows scientists to easily incorporate interactive visualization, computational steering and fault tolerance into distributed software applications. The system is a valuable tool for many large scientific applications because it enables the scientist to visually monitor large data fields and remotely control parameters inside a running application. Collaborative monitoring is provided by allowing multiple researchers to simultaneously attach to a simulation, each controlling their own view of the same or different data fields within the simulation. By supporting steering of a simulation while it is running, CUMULVS provides the opportunity to accelerate the process of scientific discovery. CUMULVS also provides a simple mechanism to incorporate automatic checkpointing and heterogeneous task migration into large applications so that simulations can continue to run for weeks unattended. This paper will give an overview of the CUMULVS system and its capabilities, including several case histories. The status of the project is described with instructions on how to obtain the software.

  16. Mid-sized omnidirectional robot with hydraulic drive and steering

    Science.gov (United States)

    Wood, Carl G.; Perry, Trent; Cook, Douglas; Maxfield, Russell; Davidson, Morgan E.

    2003-09-01

    Through funding from the US Army-Tank-Automotive and Armaments Command's (TACOM) Intelligent Mobility Program, Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS) has developed the T-series of omni-directional robots based on the USU omni-directional vehicle (ODV) technology. The ODV provides independent computer control of steering and drive in a single wheel assembly. By putting multiple omni-directional (OD) wheels on a chassis, a vehicle is capable of uncoupled translational and rotational motion. Previous robots in the series, the T1, T2, T3, ODIS, ODIS-T, and ODIS-S have all used OD wheels based on electric motors. The T4 weighs approximately 1400 lbs and features a 4-wheel drive wheel configuration. Each wheel assembly consists of a hydraulic drive motor and a hydraulic steering motor. A gasoline engine is used to power both the hydraulic and electrical systems. The paper presents an overview of the mechanical design of the vehicle as well as potential uses of this technology in fielded systems.

  17. Steering of an automated vehicle in an unstructured environment

    Science.gov (United States)

    Kanakaraju, Sampath; Shanmugasundaram, Sathish K.; Thyagarajan, Ramesh; Hall, Ernest L.

    1999-08-01

    The purpose of this paper is to describe a high-level path planning logic, which processes the data from a vision system and an ultrasonic obstacle avoidance system and steers an autonomous mobile robot between obstacles. The test bed was an autonomous root built at University of Cincinnati, and this logic was tested and debugged on this machine. Attempts have already been made to incorporate fuzzy system on a similar robot, and this paper extends them to take advantage of the robot's ZTR capability. Using the integrated vision syste, the vehicle senses its location and orientation. A rotating ultrasonic sensor is used to map the location and size of possible obstacles. With these inputs the fuzzy logic controls the speed and the steering decisions of the robot. With the incorporation of this logic, it has been observed that Bearcat II has been very successful in avoiding obstacles very well. This was achieved in the Ground Robotics Competition conducted by the AUVS in June 1999, where it travelled a distance of 154 feet in a 10ft. wide path ridden with obstacles. This logic proved to be a significant contributing factor in this feat of Bearcat II.

  18. Application of washed rumen technique for rapid determination of fasting heat production in steers

    Science.gov (United States)

    Two experiments were conducted to evaluate the use of a washed rumen technique as an alternative approach for determining fasting HP in cattle. In Exp. 1, 8 Holstein steers (322±30 kg) were adapted to a cubed alfalfa-based diet (1.5xNEm) for 10 d. After which steers were placed into individual hea...

  19. 46 CFR 122.320 - Steering gear, controls, and communication system tests.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Steering gear, controls, and communication system tests... communication system tests. The master of a vessel shall have examined and tested the steering gear, signaling whistle, propulsion controls, and communication systems of the vessel prior to getting underway for a...

  20. 46 CFR 185.320 - Steering gear, controls, and communication system tests.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Steering gear, controls, and communication system tests... gear, controls, and communication system tests. The master of a vessel shall have examined and tested the steering gear, signaling whistle, propulsion controls, and communication systems of the vessel...

  1. Modulation of the acute phase response in feedlot steers supplemented with Saccharomyces cerevisiae

    Science.gov (United States)

    This study was designed to determine the effect of supplementing feedlot steers with Saccharomyces cerevisiae CNCM I-1079 (SC) on the acute phase response to a lipopolysaccharide (LPS) challenge. Steers (n = 18; 266 ± 4 kilograms body weight) were separated into three treatment groups (n = 6/treatm...

  2. 46 CFR 131.845 - Instructions for shift of steering gear.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Instructions for shift of steering gear. 131.845 Section 131.845 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... the steering-engine room, relating, in order, the different steps to take in either shift. (b) The...

  3. 46 CFR 196.15-3 - Steering gear, whistle, and means of communication.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Steering gear, whistle, and means of communication. 196... whistle, and the means of communication between the bridge or pilothouse and engineroom shall be examined... RESEARCH VESSELS OPERATIONS Test, Drills, and Inspections § 196.15-3 Steering gear, whistle, and means of...

  4. 46 CFR 78.17-15 - Steering gear, whistle, and means of communication.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Steering gear, whistle, and means of communication. 78... whistle, and the means of communication between the bridge or pilothouse and the engine room shall be... VESSELS OPERATIONS Tests, Drills, and Inspections § 78.17-15 Steering gear, whistle, and means of...

  5. 46 CFR 109.201 - Steering gear, whistles, general alarm, and means of communication.

    Science.gov (United States)

    2010-10-01

    ..., whistles, general alarm, and means of communication. The master or person in charge shall ensure that— (a) Steering gear, whistles, general alarm bells, and means of communication between the bridge or control room... 46 Shipping 4 2010-10-01 2010-10-01 false Steering gear, whistles, general alarm, and means of...

  6. 46 CFR 97.15-3 - Steering gear, whistle, and means of communication.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Steering gear, whistle, and means of communication. 97... whistle, and the means of communication between the bridge or pilothouse and the engineroom shall be... MISCELLANEOUS VESSELS OPERATIONS Tests, Drills, and Inspections § 97.15-3 Steering gear, whistle, and means of...

  7. A theoretical model of speed-dependent steering torque for rolling tyres

    Science.gov (United States)

    Wei, Yintao; Oertel, Christian; Liu, Yahui; Li, Xuebing

    2016-04-01

    It is well known that the tyre steering torque is highly dependent on the tyre rolling speed. In limited cases, i.e. parking manoeuvre, the steering torque approaches the maximum. With the increasing tyre speed, the steering torque decreased rapidly. Accurate modelling of the speed-dependent behaviour for the tyre steering torque is a key factor to calibrate the electric power steering (EPS) system and tune the handling performance of vehicles. However, no satisfactory theoretical model can be found in the existing literature to explain this phenomenon. This paper proposes a new theoretical framework to model this important tyre behaviour, which includes three key factors: (1) tyre three-dimensional transient rolling kinematics with turn-slip; (2) dynamical force and moment generation; and (3) the mixed Lagrange-Euler method for contact deformation solving. A nonlinear finite-element code has been developed to implement the proposed approach. It can be found that the main mechanism for the speed-dependent steering torque is due to turn-slip-related kinematics. This paper provides a theory to explain the complex mechanism of the tyre steering torque generation, which helps to understand the speed-dependent tyre steering torque, tyre road feeling and EPS calibration.

  8. Modelling and Simulation of a Hydrostatic Steering System for Agricultural Tractors

    Directory of Open Access Journals (Sweden)

    Barbara Zardin

    2018-01-01

    Full Text Available The steering system of a vehicle impacts on the vehicle performance, safety and on the driver’s comfort. Moreover, in off-road vehicles using hydrostatic steering systems, the energy dissipation also becomes a critical issue. These aspects push and motivate innovation, research and analysis in the field of agricultural tractors. This paper proposes the modelling and analysis of a hydrostatic steering system for an agricultural tractor to calculate the performance of the system and determine the influence of its main design parameters. The focus here is on the driver’s steering feel, which can improve the driver’s behavior reducing unnecessary steering corrections during the working conditions. The hydrostatic steering system is quite complex and involves a hydraulic circuit and a mechanical mechanism to transmit the steering to the vehicle tires. The detailed lumped parameters model here proposed allows to simulate the dynamic behavior of the steering system and to both enhance the understanding of the system and to improve the design through parameters sensitivity analysis.

  9. The effect of supplementing rumen undegradable unsaturated fatty acids on marbling in early-weaned steers.

    Science.gov (United States)

    Mangrum, K S; Tuttle, G; Duckett, S K; Sell, G S; Krehbiel, C R; Long, N M

    2016-02-01

    The objective of this study was to determine if supplementation with a rumen undegradable unsaturated fatty acids (FA) source improved marbling deposition in early-weaned steers. All steers (Angus, = 23; Angus × Hereford, = 24) were weaned at 150 ± 5 d of age. Steers were blocked by BW and breed and then randomly assigned to either control (CON; average 1.5 kg of corn gluten feed [CGF], = 23) or isocaloric supplementation containing a rumen undegradable fat source (RUF; 200 g of Megalac-R added to an average of 1.06 kg of CGF, = 24) offered 5 d/wk for 110 d. All steers had ad libitum access to pastures throughout treatment and received supplements individually. Steer BW and blood samples were collected at 0, 55, and 110 d of supplementation, and real-time ultrasound measurements were collected at d 110. Following treatment, steers were transported to Oklahoma State University for finishing and subsequent harvesting at a commercial plant. All data were analyzed using the PROC MIXED procedure of SAS either as repeated measures or ANOVA depending on parameters. There were no significant changes in BW from the beginning of treatment to harvest due to treatment. Ultrasound data showed that RUF steers tended ( = 0.08) to have more i.m. fat than CON at d 110. Serum concentrations of FA showed a treatment × day interaction ( unsaturated FA can positively impact marbling deposition in early-weaned steers without impacting other carcass measures.

  10. On Using Current Steering Logic in Mixed Analogue-digital Circuits

    DEFF Research Database (Denmark)

    Lehmann, Torsten

    1998-01-01

    The authors investigate power supply noise in mixed analogue-digital circuits, arising from communication between the analogue and digital parts of the circuit. Current steering techniques and proper buffering are used to show which noise currents can be reduced and which cannot. In addition......, a high-swing current steering buffer for driving analogue switches or external digital signals is proposed....

  11. comparative beef production from buli,s, steers and heifers under

    African Journals Online (AJOL)

    steers, although statistically significant, were much srnaller than differences obtained in the present study. Out of a maximum possible grading of 20 points, bulls obtained an average of 12,3 points (Grade I -) which is considerably lower than the grading points obtained by steers (16,3 = Prime) or by heifers (17,5 = Prime+).

  12. Steer-by-wire system for the Motor-Kart vehicle of FH Cologne University; Steer-by-Wire-Lenkung fuer den Motor-Kart der FH Koeln

    Energy Technology Data Exchange (ETDEWEB)

    Baum, H. [Fluidon GmbH, Aachen (Germany); Ulrich, H. [FH Koeln (Germany). Inst. fuer Fahrzeugtechnik; Hermanns, O. [LMS Deutschland GmbH, Kaiserslautern (Germany)

    2005-12-01

    In the course of semester projects, students of FH Cologne, Institute of Motor Car Engineering, get their first experience with the increasingly complex development processes of modern vehicle systems. Using the example of a steer-by-wire system, the contribution outlines the steps taken by the students. One of the key elements of the project was the development of the steer-by-wire control by coupling the control unit to the detailed simulation model of the Motor-Kart vehicle. (orig.)

  13. An Innovative Steering System for a River Push Barge Operated in Environmentally Sensitive Areas

    Directory of Open Access Journals (Sweden)

    Abramowicz-Gerigk Teresa

    2017-12-01

    Full Text Available The paper presents an innovative steering system for a river push barge dedicated for operation in environmentally sensitive inland waterways. Development of the inland waterborne transport in Poland is dependent on the exploitation of rivers which can be adapted to navigation in the limited range because a high percent of their length is classified within special environment protection areas of Natura 2000 network. This is now the main reason that their better exploitation cannot be obtained without an introduction of a new generation of waterborne environment friendly inland units. In naturally winding rivers with differing and rapidly changing depths and widths it is important to equip a push barge with an efficient steering system that has a low environmental impact. The innovative steering system proposed in the paper is composed of main steering devices located at the pusher stern, auxiliary steering devices installed on the barge bow and a mechanical coupling system.

  14. Collision-model approach to steering of an open driven qubit

    Science.gov (United States)

    Beyer, Konstantin; Luoma, Kimmo; Strunz, Walter T.

    2018-03-01

    We investigate quantum steering of an open quantum system by measurements on its environment in the framework of collision models. As an example we consider a coherently driven qubit dissipatively coupled to a bath. We construct local nonadaptive and adaptive as well as nonlocal measurement scenarios specifying explicitly the measured observable on the environment. Our approach shows transparently how the conditional evolution of the open system depends on the type of the measurement scenario and the measured observables. These can then be optimized for steering. The nonlocal measurement scenario leads to maximal violation of the used steering inequality at zero temperature. Further, we investigate the robustness of the constructed scenarios against thermal noise. We find generally that steering becomes harder at higher temperatures. Surprisingly, the system can be steered even when bipartite entanglement between the system and individual subenvironments vanishes.

  15. Facilitating Knowledge Sharing

    DEFF Research Database (Denmark)

    Holdt Christensen, Peter

    Abstract This paper argues that knowledge sharing can be conceptualized as different situations of exchange in which individuals relate to each other in different ways, involving different rules, norms and traditions of reciprocity regulating the exchange. The main challenge for facilitating...... and the intermediaries regulating the exchange, and facilitating knowledge sharing should therefore be viewed as a continuum of practices under the influence of opportunistic behaviour, obedience or organizational citizenship behaviour. Keywords: Knowledge sharing, motivation, organizational settings, situations...

  16. Avoiding Internal Capsule Stimulation With a New Eight-Channel Steering Deep Brain Stimulation Lead.

    Science.gov (United States)

    van Dijk, Kees J; Verhagen, Rens; Bour, Lo J; Heida, Ciska; Veltink, Peter H

    2017-10-15

    Novel deep brain stimulation (DBS) lead designs are currently entering the market, which are hypothesized to provide a way to steer the stimulation field away from neural populations responsible for side effects and towards populations responsible for beneficial effects. The objective of this study is to assess the performances of a new eight channel steering-DBS lead and compare this with a conventional cylindrical contact (CC) lead. The two leads were evaluated in a finite element electric field model combined with multicompartment neuron and axon models, representing the internal capsule (IC) fibers and subthalamic nucleus (STN) cells. We defined the optimal stimulation setting as the configuration that activated the highest percentage of STN cells, without activating any IC fibers. With this criterion, we compared monopolar stimulation using a single contact of the steering-DBS lead and CC lead, on three locations and four orientations of the lead. In addition, we performed a current steering test case by dividing the current over two contacts with the steering-DBS lead in its worst-case orientation. In most cases, the steering-DBS lead is able to stimulate a significantly higher percentage of STN cells compared to the CC lead using single contact stimulation or using a two contact current steering protocol when there is approximately a 1 mm displacement of the CC lead. The results also show that correct placement and orientation of the lead in the target remains an important aspect in achieving the optimal stimulation outcome. Currently, clinical trials are set up in Europe with a similar design as the steering-DBS lead. Our results illustrate the importance of the orientation of the new steering-DBS lead in avoiding side effects induced by stimulation of IC fibers. Therefore, in clinical trials sufficient attention should be paid to implanting the steering DBS-lead in the most effective orientation. © 2017 International Neuromodulation Society.

  17. Sugar transport across lactose permease probed by steered molecular dynamics

    DEFF Research Database (Denmark)

    Jensen, Morten Østergaard; Yin, Ying; Tajkhorshid, Emad

    2007-01-01

    Escherichia coli lactose permease (LacY) transports sugar across the inner membrane of the bacterium using the proton motive force to accumulate sugar in the cytosol. We have probed lactose conduction across LacY using steered molecular dynamics, permitting us to follow molecular and energetic...... details of lactose interaction with the lumen of LacY during its permeation. Lactose induces a widening of the narrowest parts of the channel during permeation, the widening being largest within the periplasmic half-channel. During permeation, the water-filled lumen of LacY only partially hydrates lactose......, forcing it to interact with channel lining residues. Lactose forms a multitude of direct sugar-channel hydrogen bonds, predominantly with residues of the flexible N-domain, which is known to contribute a major part of LacY's affinity for lactose. In the periplasmic half-channel lactose predominantly...

  18. Fractional Control of An Active Four-wheel-steering Vehicle

    Science.gov (United States)

    Wang, Tianting; Tong, Jun; Chen, Ning; Tian, Jie

    2018-03-01

    A four-wheel-steering (4WS) vehicle model and reference model with a drop filter are constructed. The decoupling of 4WS vehicle model is carried out. And a fractional PIλDμ controller is introduced into the decoupling strategy to reduce the effects of the uncertainty of the vehicle parameters as well as the unmodelled dynamics on the system performance. Based on optimization techniques, the design of fractional controller are obtained to ensure the robustness of 4WS vehicle during the special range of frequencies through proper choice of the constraints. In order to compare with fractional robust controller, an optimal controller for the same vehicle is also designed. The simulations of the two control systems are carried out and it reveals that the decoupling and fractional robust controller is able to make vehicle model trace the reference model very well with better robustness.

  19. Planning analysis and political steering with New Public Management

    DEFF Research Database (Denmark)

    Sager, Tore Øivin; Sørensen, Claus Hedegaard

    2011-01-01

    of interviews sheds light on the apparent paradox that parliamentarians accept delegation of highway investment decisions despite their profound scepticism to the cost-benefit analyses and impact calculations that are essential to management by objectives and results, which was to give them continued political......Interviews with members of the Norwegian national assembly’s Standing Committee for Transport and Communications were conducted in 1995, 1997, 2001, and 2004. The politicians were asked about the usefulness of analytic input that planners contribute to national plans, first the Norwegian Road...... and Road Traffic Plan and later the National Transport Plan. Questions related to steering, coordination, delegation, and the inclusiveness of the planning process were also posed. Changes in the politicians’ attitudes to types of analytic planning input are outlined. Furthermore, the last round...

  20. DYNAMICS BASED CONTROL OF A SKID STEERING MOBILE ROBOT

    Directory of Open Access Journals (Sweden)

    Osama Elshazly

    2016-06-01

    Full Text Available In this paper, development of a reduced order, augmented dynamics-drive model that combines both the dynamics and drive subsystems of the skid steering mobile robot (SSMR is presented. A Linear Quadratic Regulator (LQR control algorithm with feed-forward compensation of the disturbances part included in the reduced order augmented dynamics-drive model is designed. The proposed controller has many advantages such as its simplicity in terms of design and implementation in comparison with complex nonlinear control schemes that are usually designed for this system. Moreover, the good performance is also provided by the controller for the SSMR comparable with a nonlinear controller based on the inverse dynamics which depends on the availability of an accurate model describing the system. Simulation results illustrate the effectiveness and enhancement provided by the proposed controller.

  1. Adiabatically steered open quantum systems: Master equation and optimal phase

    International Nuclear Information System (INIS)

    Salmilehto, J.; Solinas, P.; Ankerhold, J.; Moettoenen, M.

    2010-01-01

    We introduce an alternative way to derive the generalized form of the master equation recently presented by J. P. Pekola et al. [Phys. Rev. Lett. 105, 030401 (2010)] for an adiabatically steered two-level quantum system interacting with a Markovian environment. The original derivation employed the effective Hamiltonian in the adiabatic basis with the standard interaction picture approach but without the usual secular approximation. Our approach is based on utilizing a master equation for a nonsteered system in the first superadiabatic basis. It is potentially efficient in obtaining higher-order equations. Furthermore, we show how to select the phases of the adiabatic eigenstates to minimize the local adiabatic parameter and how this selection leads to states which are invariant under a local gauge change. We also discuss the effects of the adiabatic noncyclic geometric phase on the master equation.

  2. Detection of genuine tripartite entanglement and steering in hybrid optomechanics.

    Science.gov (United States)

    Xiang, Y; Sun, F X; Wang, M; Gong, Q H; He, Q Y

    2015-11-16

    Multipartite quantum entanglement is a key resource for ensuring security in quantum network. We show that by using a unified parameter in terms of reduced noise variances one can determine different types of tripartite entanglement of a given state generated in a hybrid optomechanical system, where an atomic ensemble is located inside a single-mode cavity with a movable mirror, with different thresholds for each type. In particular, the special quantum states which allow both entanglement and steering genuinely shared among atom-light-mirror modes can be observed, even though there is no direct interaction between the mirror and the atomic ensemble. We further show the robustness against mechanical thermal noise and damping, the relaxation time of atomic ensemble, as well as the effect of gain factors involved in the criteria. Our analysis provides an experimentally achievable method to determine the type of tripartite quantum correlation in a way.

  3. Model projections of atmospheric steering of Sandy-like superstorms.

    Science.gov (United States)

    Barnes, Elizabeth A; Polvani, Lorenzo M; Sobel, Adam H

    2013-09-17

    Superstorm Sandy ravaged the eastern seaboard of the United States, costing a great number of lives and billions of dollars in damage. Whether events like Sandy will become more frequent as anthropogenic greenhouse gases continue to increase remains an open and complex question. Here we consider whether the persistent large-scale atmospheric patterns that steered Sandy onto the coast will become more frequent in the coming decades. Using the Coupled Model Intercomparison Project, phase 5 multimodel ensemble, we demonstrate that climate models consistently project a decrease in the frequency and persistence of the westward flow that led to Sandy's unprecedented track, implying that future atmospheric conditions are less likely than at present to propel storms westward into the coast.

  4. Model projections of atmospheric steering of Sandy-like superstorms

    Science.gov (United States)

    Barnes, Elizabeth A.; Polvani, Lorenzo M.; Sobel, Adam H.

    2013-01-01

    Superstorm Sandy ravaged the eastern seaboard of the United States, costing a great number of lives and billions of dollars in damage. Whether events like Sandy will become more frequent as anthropogenic greenhouse gases continue to increase remains an open and complex question. Here we consider whether the persistent large-scale atmospheric patterns that steered Sandy onto the coast will become more frequent in the coming decades. Using the Coupled Model Intercomparison Project, phase 5 multimodel ensemble, we demonstrate that climate models consistently project a decrease in the frequency and persistence of the westward flow that led to Sandy’s unprecedented track, implying that future atmospheric conditions are less likely than at present to propel storms westward into the coast. PMID:24003129

  5. Lightweight computational steering of very large scale molecular dynamics simulations

    International Nuclear Information System (INIS)

    Beazley, D.M.

    1996-01-01

    We present a computational steering approach for controlling, analyzing, and visualizing very large scale molecular dynamics simulations involving tens to hundreds of millions of atoms. Our approach relies on extensible scripting languages and an easy to use tool for building extensions and modules. The system is extremely easy to modify, works with existing C code, is memory efficient, and can be used from inexpensive workstations and networks. We demonstrate how we have used this system to manipulate data from production MD simulations involving as many as 104 million atoms running on the CM-5 and Cray T3D. We also show how this approach can be used to build systems that integrate common scripting languages (including Tcl/Tk, Perl, and Python), simulation code, user extensions, and commercial data analysis packages

  6. Fast-steering solutions for cubesat-scale optical communications

    Science.gov (United States)

    Kingsbury, R. W.; Nguyen, T.; Riesing, K.; Cahoy, K.

    2017-11-01

    We describe the design of a compact free-space optical communications module for use on a nanosatellite and present results from a detailed trade study to select an optical fine steering mechanism compatible with our stringent size, weight and power (SWaP) constraints. This mechanism is an integral component of the compact free-space optical communications system that is under development at the MIT Space Systems Laboratory [1]. The overall goal of this project is to develop a laser communications (lasercom) payload that fits within the SWaP constraints of a typical ``3U'' CubeSat. The SWaP constraints for the entire lasercom payload are 5 cm × 10 cm × 10 cm, 600 g and 10W. Although other efforts are underway to qualify MEMS deformable mirrors for use in CubeSats [2], there has been very little work towards qualifying tip-tilt MEMS mirrors [3]. Sec. II provides additional information on how the fast steering mechanism is used in our lasercom system. Performance requirements and desirable traits of the mechanism are given. In Sec. III we describe the various types of compact tip-tilt mirrors that are commercially available as well as the justification for selecting a MEMS-based device for our application. Sec. IV presents an analysis of the device's transfer function characteristics and ways of predicting this behavior that are suitable for use in the control processor. This analysis is based upon manufacturer-provided test data which was collected at standard room conditions. In the final section, we describe on-going work to build a testbed that will be used to measure device performance in a thermal chamber.

  7. Chronic Total Occlusion-Angioplasty with Antegrade Approach: A two-Year Experience in “Modarres Hospital”, A Tertiary University Hospital, Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Morteza Safi

    2016-10-01

    Full Text Available Introduction: New techniques for the percutaneous treatment of coronary chronic total occlusions (CTO have had a high success rate since a few years ago, so the interest for this treatment has been increasing these days.Methods: The current observational study was performed in Modarres hospital as a tertiary referral center. All the patients with documented stable angina who had failed to response to full guideline-mediated medical therapy, referred to our hospital, were candidates for coronary angiography. Antegrade strategy was applied for all these patients. The length of the lesion, the fluoroscopy time of the CTO angioplasty, consumed contrast volume, the number of guide wires used, whether a corsair or tornus micro-catheter was used or not, and the success rate of the angioplasty were documented for further analysis.Results: A total of 47 patients with documented stable angina were finally included. The median age was 59 (45-78 and 70.2% were male. The mean length of the lesion was 34.0 ± 1.1 .The mean fluoroscopy time and contrast volume were 57.9 ± 3.2 minutes and 525.9 ± 20.9 mL, respectively. In average, 2.2 guide wires were used. Corsair and tornus micro-catheters were applied in 30 (63.8% and 5 (10.6% of the cases, respectively. Seven complications (all including coronary dissection occurred. In-hospital major adverse cardiac events (MACE rate was 10.6%, all of which were non-Q wave myocardial infarction. The success rate was 85.1%. The higher number of used wires, use of corsair, and tornus micro-catheter were not significantly concordant with success rate (P-value > 0.05; in addition, longer lesion was not concordant with unsuccessfulness rate (P-value > 0.05.Conclusions: Patient selection for CTO-angioplasty should be performed more carefully. Patients’ quality of life and risk of probable procedural complications and future cardiac events should be assessed to decide the best treatment approach. Radiation exposure, contrast

  8. Computer-assisted three-dimensional correlation between the femoral neck-shaft angle and the optimal entry point for antegrade nailing.

    Science.gov (United States)

    Anastopoulos, George; Chissas, Dionisios; Dourountakis, Joseph; Ntagiopoulos, Panagiotis G; Magnisalis, Evaggelos; Asimakopoulos, Antonios; Xenakis, Theodore A

    2010-03-01

    Optimal entry point for antegrade femoral intramedullary nailing (IMN) remains controversial in the current medical literature. The definition of an ideal entry point for femoral IMN would implicate a tenseless introduction of the implant into the canal with anatomical alignment of the bone fragments. This study was undertaken in order to investigate possible existing relationships between the true 3D geometric parameters of the femur and the location of the optimum entry point. A sample population of 22 cadaveric femurs was used (mean age=51.09+/-14.82 years). Computed-tomography sections every 0.5mm for the entire length of femurs were produced. These sections were subsequently reconstructed to generate solid computer models of the external anatomy and medullary canal of each femur. Solid models of all femurs were subjected to a series of geometrical manipulations and computations using standard computer-aided-design tools. In the sagittal plane, the optimum entry point always lied a few millimeters behind the femoral neck axis (mean=3.5+/-1.5mm). In the coronal plane the optimum entry point lied at a location dependent on the femoral neck-shaft angle. Linear regression on the data showed that the optimal entry point is clearly correlated to the true 3D femoral neck-shaft angle (R(2)=0.7310) and the projected femoral neck-shaft angle (R(2)=0.6289). Anatomical parameters of the proximal femur, such as the varus-valgus angulation, are key factors in the determination of optimal entry point for nailing. The clinical relevance of the results is that in varus hips (neck-shaft angle shaft angle between 120 degrees and 130 degrees , the optimal entry point lies just medially to the trochanter tip (at the piriformis fossa) and the use of stiff implants is safe. In hips with neck-shaft angle over 130 degrees the anatomical axis of the canal is medially to the base of the neck, in a "restricted area". In these cases the entry point should be located at the insertion of the

  9. Test of Einstein-Podolsky-Rosen steering based on the all-versus-nothing proof.

    Science.gov (United States)

    Wu, Chunfeng; Chen, Jing-Ling; Ye, Xiang-Jun; Su, Hong-Yi; Deng, Dong-Ling; Wang, Zhenghan; Oh, C H

    2014-03-06

    In comparison with entanglement and Bell nonlocality, Einstein-Podolsky-Rosen steering is a newly emerged research topic and in its incipient stage. Although Einstein-Podolsky-Rosen steering has been explored via violations of steering inequalities both theoretically and experimentally, the known inequalities in the literatures are far from well-developed. As a result, it is not yet possible to observe Einstein-Podolsky-Rosen steering for some steerable mixed states. Recently, a simple approach was presented to identify Einstein-Podolsky-Rosen steering based on all-versus-nothing argument, offering a strong condition to witness the steerability of a family of two-qubit (pure or mixed) entangled states. In this work, we show that the all-versus-nothing proof of Einstein-Podolsky-Rosen steering can be tested by measuring the projective probabilities. Through the bound of probabilities imposed by local-hidden-state model, the proposed test shows that steering can be detected by the all-versus-nothing argument experimentally even in the presence of imprecision and errors. Our test can be implemented in many physical systems and we discuss the possible realizations of our scheme with non-Abelian anyons and trapped ions.

  10. Performance on steering power ratio of tracked vehicles influenced by soil parameters

    Directory of Open Access Journals (Sweden)

    Chi Yuan

    2015-01-01

    Full Text Available In order to study tracked vehicle adopting different steering mechanism, we use steering power ratio to evaluate its performance. The influencing factors of steering power ratio have been theoretically studied. And we designed the experimental prototype to test. We find that steering power ratio is related to vehicle parameters, resistance coefficient, turning radius, skid ratio, slip ratio and steering coefficient not only, but also it is related to soil parameters (including soil cohesion, internal friction angle of soil and shear modulus of soil. On the condition that vehicle parameters and resistance coefficient are determined, the soil shear tests were carried out, which acquired that the average moisture content of soil is 16.85%,soil cohesion is 14.071 Kpa, internal friction angle of soil is 17.93°, and shear modulus of soil is 0.00027 m. Through being researched, steering power ratio is related to turning radius, skid ratio and slip ratio, which has the important significance on the study of steering power ratio.

  11. From Teaching to Facilitation

    DEFF Research Database (Denmark)

    de Graaff, Erik

    2013-01-01

    A shift from teaching to learning is characteristic of the introduction of Problem Based Learning (PBL) in an existing school. As a consequence the teaching staff has to be trained in skills like facilitating group work and writing cases. Most importantly a change in thinking about teaching...... and learning will have to be realized. In the implementation of PBL it makes a difference how the core features of the problem and the role of the facilitator have been defined. This paper will present components of a PBL faculty-development training programme and discuss the relevance with respect...

  12. Coal export facilitation

    International Nuclear Information System (INIS)

    Eeles, L.

    1998-01-01

    There is a wide range of trade barriers, particularly tariffs, in current and potential coal market. Commonwealth departments in Australia play a crucial role in supporting government industry policies. This article summarises some of more recent activities of the Department of Primary Industries and Energy (DPIE) in facilitating the export of Australian Coals. Coal export facilitation activities are designed to assist the Australian coal industry by directing Commonwealth Government resources towards issues which would be inappropriate or difficult for the industry to address itself

  13. The Influence Of The Ship's Steering Machine Over Yaw And Roll Motions

    Directory of Open Access Journals (Sweden)

    Viorel NICOLAU

    2003-12-01

    Full Text Available The steering machine is a nonlinear system, with two important limitations: the maximum rudder angle and rudder rate. Therefore, the commands from yaw and rudder-roll control systems are modified and the expected effect is not always the optimum one. It is important to know the influence of the steering machine, trying to avoid the limitations or to include them into the control law. The goal of this paper is to analyze the steering machine limitations and their influence over yaw and roll motions of the ship. Also, some expert rules are generated, which can be used to implement more efficient control laws.

  14. Evaluation of Meat Color and Physiochemical Characteristics in Forequarter Muscles of Holstein Steers.

    Science.gov (United States)

    Moon, Sung Sil; Seong, Pil-Nam; Jeong, Jin Young

    2015-01-01

    The beef forequarter muscle comprises approximately 52% of carcass weight. The objective of this study was to evaluate the physiochemical characteristics and meat color from forequarter muscle of Holstein steers. Fifteen forequarter muscles were trimmed of external connective tissue and fat. An experimental group of eight Holstein steers was assessed using meat color, water-holding capacity, drip loss, and Warner-Bratzler shear force value at the same quality grade. The M. omotransversarius (0.45 kg) had the highest (pphysiochemical characteristics. Thus, our findings suggest that these muscle profile data will allow for more informed decisions when selecting individual muscles to produce value-added products from Holstein steers.

  15. The challenges of facilitation

    DEFF Research Database (Denmark)

    Agger, Annika

    The aim of the paper is to investigate the role of the facilitators in the enactment of the principles of deliberative democracy and how they are carried out in practice. More specifically, the focus is on how the facilitators‟ balances between the intention of opening up for a plurality of voice...

  16. Facilitating leadership team communication

    OpenAIRE

    Hedman, Eerika

    2015-01-01

    The purpose of this study is to understand and describe how to facilitate competent communication in leadership teamwork. Grounded in the premises of social constructionism and informed by such theoretical frameworks as coordinated management of meaning theory (CMM), dialogic organization development (OD), systemic-constructionist leadership, communication competence, and reflexivity, this study seeks to produce further insights into understanding leadership team communicati...

  17. Comparison of vibration damping of standard and PDCPD housing of the electric power steering system

    Science.gov (United States)

    Płaczek, M.; Wróbel, A.; Baier, A.

    2017-08-01

    A comparison of two different types of electric power steering system housing is presented. The first considered type of the housing was a standard one that is made of an aluminium alloy. The second one is made of polydicyclopentadiene polymer (PDCPD) and was produced using the RIM technology. Considered elements were analysed in order to verify their properties of vibrations damping. This property is very important taking into account noise generated by elements of a car’s power steering system. During the carried out tests vibrations of analysed power steering housings were measured using Marco Fiber Composite (MFC) piezoelectric transducers. Results obtained for both considered power steering housings in case of the same parameters of vibrations excitations were measured and juxtaposed. Obtained results were analysed in order to verify if the housing made of PDCPD polymer has better properties of vibration damping than the standard one.

  18. Effect of monensin and monensin and tylosin combination on feed intake variation of feedlot steers.

    Science.gov (United States)

    Stock, R A; Laudert, S B; Stroup, W W; Larson, E M; Parrott, J C; Britton, R A

    1995-01-01

    A trial involving four commercial feedlots and an individual feeding trial evaluated the effect of monensin and monensin/tylosin on intake variation and deaths from digestive disorders. Four commercial feedlots in Texas and Colorado fed 2,904 yearling crossbred steers (340 kg) high-grain diets containing approximately 82% grain, 8% silage and alfalfa hay, 4% fat, and 6% supplement (DM basis). Steers were allotted randomly to one of three monensin/tylosin levels: 1) no monensin or tylosin (control); 2) 22 mg/kg of monensin and 11 mg/kg of tylosin; or 3) 33 mg/kg of monensin and 11 mg/kg of tylosin. Monensin/tylosin reduced DMI (P tylosin reduce feed intake variation among individual steers within a pen of steers. Pen means mask individual animal variation to the point that it is difficult to detect treatment differences.

  19. National Status and Trends: Bioeffects Program - St. Thomas East End Reserves (STEER) Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this effort was to characterize the extent and magnitude of chemical contamination in the St. Thomas East End Reserves or STEER, as part of a larger...

  20. Effects of clay on fat necrosis and carcass characteristics in Japanese Black steers.

    Science.gov (United States)

    Oka, Akio; Iwamoto, Eiji; Tatsuda, Ken

    2015-10-01

    Twenty 10-month-old Japanese Black steers were used to evaluate the effects of clay on fat necrosis and carcass characteristics. Ten steers (Clay group) were fed the clay (50 g/day) during 10-30 months of age. The other 10 steers (Control group) were not fed it. There was no significant difference in body weight or average daily gain between the two groups (P > 0.05). The occurrence of fat necrotic mass in the Clay group (30%) was lower (P Clay group was smaller (P clay prevented the occurrence of fat necrosis and did not affect the carcass characteristics in Japanese Black steers. © 2015 Japanese Society of Animal Science.

  1. Ka-Band Electronically Steered CubeSat Antenna, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Kymeta Government Solutions (KGS) designed, analyzed, built, tested, and delivered a small, lightweight, low-cost, low-power electronically steered Ka-band prototype...

  2. Fault Risk Assessment of Underwater Vehicle Steering System Based on Virtual Prototyping and Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    He Deyu

    2016-09-01

    Full Text Available Assessing the risks of steering system faults in underwater vehicles is a human-machine-environment (HME systematic safety field that studies faults in the steering system itself, the driver’s human reliability (HR and various environmental conditions. This paper proposed a fault risk assessment method for an underwater vehicle steering system based on virtual prototyping and Monte Carlo simulation. A virtual steering system prototype was established and validated to rectify a lack of historic fault data. Fault injection and simulation were conducted to acquire fault simulation data. A Monte Carlo simulation was adopted that integrated randomness due to the human operator and environment. Randomness and uncertainty of the human, machine and environment were integrated in the method to obtain a probabilistic risk indicator. To verify the proposed method, a case of stuck rudder fault (SRF risk assessment was studied. This method may provide a novel solution for fault risk assessment of a vehicle or other general HME system.

  3. Facilitating Learning at Conferences

    DEFF Research Database (Denmark)

    Ravn, Ib; Elsborg, Steen

    2011-01-01

    The typical conference consists of a series of PowerPoint presentations that tend to render participants passive. Students of learning have long abandoned the transfer model that underlies such one-way communication. We propose an al-ternative theory of conferences that sees them as a forum...... for learning, mutual inspiration and human flourishing. We offer five design principles that specify how conferences may engage participants more and hence increase their learning. In the research-and-development effort reported here, our team collaborated with conference organizers in Denmark to introduce...... and facilitate a variety of simple learning techniques at thirty one- and two-day conferences of up to 300 participants each. We present ten of these techniques and data evaluating them. We conclude that if conference organizers allocate a fraction of the total conference time to facilitated processes...

  4. Essence: Facilitating Software Innovation

    DEFF Research Database (Denmark)

    Aaen, Ivan

    2008-01-01

      This paper suggests ways to facilitate creativity and innovation in software development. The paper applies four perspectives – Product, Project, Process, and People –to identify an outlook for software innovation. The paper then describes a new facility–Software Innovation Research Lab (SIRL) ......) – and a new method concept for software innovation – Essence – based on views, modes, and team roles. Finally, the paper reports from an early experiment using SIRL and Essence and identifies further research.......  This paper suggests ways to facilitate creativity and innovation in software development. The paper applies four perspectives – Product, Project, Process, and People –to identify an outlook for software innovation. The paper then describes a new facility–Software Innovation Research Lab (SIRL...

  5. Mindfulness for group facilitation

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2014-01-01

    thinking and ‘Eastern’ mindfulness which refers to an open, accepting state of mind, as intended with Buddhist-inspired techniques such as meditation. In this paper, we are interested in the latter type of mindfulness and demonstrate how Eastern mindfulness techniques can be used as a tool for facilitation......In this paper, we argue that mindfulness techniques can be used for enhancing the outcome of group performance. The word mindfulness has different connotations in the academic literature. Broadly speaking there is ‘mindfulness without meditation’ or ‘Western’ mindfulness which involves active....... A brief introduction to the physiology and philosophy of Eastern mindfulness constitutes the basis for the arguments of the effect of mindfulness techniques. The use of mindfulness techniques for group facilitation is novel as it changes the focus from individuals’ mindfulness practice...

  6. Laser facilitates vaccination

    Directory of Open Access Journals (Sweden)

    Ji Wang

    2016-01-01

    Full Text Available Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces: to improve vaccine efficacy without compromising safety. Harnessing the specific effects of laser on biological systems, a number of novel concepts have been proposed and proved in recent years to facilitate vaccination in a safer and more efficient way. The key advantage of using laser technology in vaccine delivery and adjuvantation is that all processes are initiated by physical effects with no foreign chemicals administered into the body. Here, we review the recent advances in using laser technology to facilitate vaccine delivery and augment vaccine efficacy as well as the underlying mechanisms.

  7. Containers, facilitators, innovators?

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Merisalo, Maria; Inkinen, Tommi

    2018-01-01

    : are they containers, facilitators or innovators? This is investigated here through empirical material derived from 27 interviews with top departmental management in three Finnish cities (Helsinki, Espoo and Vantaa). The results show that local city governments (LCGs) consider cities as facilitators of innovation...... without the active role of LCGs as innovators. City employees are innovative – the seeming lack of public sector innovation is actually a result of measurement issues that favour (patentable) technological innovations rather than those more common to LCGs, meaning service and organisational types....... Therefore, LCGs can be seen as highly innovative organisations. There are, however, barriers to innovation in the public sector, such as the cost of innovation activity, the lack of incentives for it, and working culture that does not support it. Lastly, the results show that LCGs have not really fully...

  8. Facilitating Knowledge Sharing

    OpenAIRE

    Holdt Christensen, Peter

    2005-01-01

    Abstract This paper argues that knowledge sharing can be conceptualized as different situations of exchange in which individuals relate to each other in different ways, involving different rules, norms and traditions of reciprocity regulating the exchange. The main challenge for facilitating knowledge sharing is to ensure that the exchange is seen as equitable for the parties involved, and by viewing the problems of knowledge sharing as motivational problems situated in different organization...

  9. Influence of Road Excitation and Steering Wheel Input on Vehicle System Dynamic Responses

    OpenAIRE

    Zhen-Feng Wang; Ming-Ming Dong; Liang Gu; Jagat-Jyoti Rath; Ye-Chen Qin; Bin Bai

    2017-01-01

    Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steer...

  10. A Method for Eliminating Beam Steering Error for the Modulated Absorption-Emission Thermometry Technique

    Science.gov (United States)

    2015-01-01

    Beam Steering Error for the Modulated Absorption-Emission Thermometry Technique 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...Jan 2015. PA#14562. 14. ABSTRACT Modulated absorption-emission thermometry (MAET) is a non-intrusive, radiometric technique for measuring line-of...ANSI Std. 239.18 1 Integrity  Service  Excellence A Method for Eliminating Beam Steering Error for Modulated Absorption- Emission Thermometry

  11. Measurement and Analysis of Strains Developed on Tie-rods of a Steering System

    OpenAIRE

    Asenov, Stefan

    2016-01-01

    Modern day manufacturers research and develop vehicles that are equipped with steering assist to help drivers undertake manoeuvres. However the lack of research for a situation where one tie-rod experiences different strains than the opposite one leads to failure in the tie-rod assembly and misalignment in the wheels over time. The performance of the steering system would be improved if this information existed. This bachelor’s dissertation looks into this specific situation and cond...

  12. IODE Steering Group for MEDI: Third Session Drexel University Philadelphia, USA 11-13 September 2006.

    OpenAIRE

    IOC for UNESCO

    2006-01-01

    The Marine Environmental Data Information Referral Catalogue (MEDI) is a directory system for datasets, data catalogues and data inventories developed by IODE. The IODE Steering Group for MEDI was established to support the MEDI system. During its Third Session the Steering Group discussed the implementation of a marine community profile of the ISO 19115 metadata standard. The marine community profile developed by the Australian Ocean Data Centre Joint Facility will be disseminated for commen...

  13. Antegrade nailing of femoral shaft fractures combined with neck or distal femur fractures. A retrospective review of 25 cases, with a follow-up of 36-150 months.

    Science.gov (United States)

    Okcu, Güvenir; Aktuglu, Kemal

    2003-12-01

    Complex femoral fractures pose considerable therapeutic challenges to orthopedic surgeons. We present a retrospective review of 25 patients with complex femoral fractures treated with intramedullary locked nailing and supplemental screw fixation. Fifteen patients with ipsilateral femoral neck and shaft fractures (group 1) and 10 patients with ipsilateral femoral shaft and distal femur fractures (group 2) were treated from 1990 to 1998. High-energy injuries occurred in all patients. There were 4 open fractures. Antegrade, locked nailing of diaphyseal fractures was performed in all cases. Supplemental screws for the neck were used in all patients in group 1 and in 3 patients in group 2. All of the fractures united during the follow-up. Five patients in group 1 underwent reoperation (33.3%): one due to a delayed union, the second due to an implant failure, the third due to a nonunion of a neck fracture, and the last two because of an initially missed femoral neck fracture. None of the patients in group 2 underwent reoperation. Angular malalignment of the shaft was found in 6 fractures in group 1 (average 4.8 degree, range 3 degree-11 degree) and in 4 fractures in group 2 (average 6 degree, range 3 degree-12 degree). Shortening of the limb occurred in 3 patients in group 1 (average 1.4 cm, range 1-1.8) and in 1 patient in group 2 (2 cm). Loss of fixation was seen in 1 patient in each group. Avascular necrosis and infection were not seen in any case in both groups. Femoral intramedullary nails with antegrade or retrograde options for insertion and different locking possibilities have extended the indications to include both diaphyseal and metaphyseal fractures. New nail designs, usually more expensive than the conventional nails, have been introduced into the market for this purpose. One has to keep in mind that antegrade, locked nailing of femoral shaft fractures combined with neck or distal femur fractures is a technically demanding but efficacious procedure. The

  14. Global Chassis Control System Using Suspension, Steering, and Braking Subsystems

    Directory of Open Access Journals (Sweden)

    Carlos A. Vivas-Lopez

    2015-01-01

    Full Text Available A novel Global Chassis Control (GCC system based on a multilayer architecture with three levels: top: decision layer, middle: control layer, and bottom: system layer is presented. The main contribution of this work is the development of a data-based classification and coordination algorithm, into a single control problem. Based on a clustering technique, the decision layer classifies the current driving condition. Afterwards, heuristic rules are used to coordinate the performance of the considered vehicle subsystems (suspension, steering, and braking using local controllers hosted in the control layer. The control allocation system uses fuzzy logic controllers. The performance of the proposed GCC system was evaluated under different standard tests. Simulation results illustrate the effectiveness of the proposed system compared to an uncontrolled vehicle and a vehicle with a noncoordinated control. The proposed system decreases by 14% the braking distance in the hard braking test with respect to the uncontrolled vehicle, the roll and yaw movements are reduced by 10% and 12%, respectively, in the Double Line Change test, and the oscillations caused by load transfer are reduced by 7% in a cornering situation.

  15. The ATLAS High Level Trigger Configuration and Steering

    CERN Document Server

    Stelzer, J; The ATLAS collaboration

    2010-01-01

    In March 2010 the four LHC experiments saw the first proton-proton collisions at 7 TeV. Still within the year a collision rate of nearly 10 MHz is expected. At ATLAS, events of potential interest for ATLAS physics are selected by a three level trigger system, with a final recording rate of about 200 Hz. The first level (L1) is implemented in customized hardware, the two levels of the high level trigger (HLT) are software triggers. Within the ATLAS physics program more than 500 trigger signatures are defined. The HLT tests each signature on each L1-accepted event, the test outcome is recorded for later analysis. The HLT-Steering is responsible for this. It foremost ensures the independent test of each signature, guarantying unbiased trigger decisions. Yet, to minimize data readout and execution time, cached detector data and once-calculated trigger objects are reused to form the decision. Some signature tests are performed only on a scaled-down fraction of candidate events, in order to reduce the output rate a...

  16. Autonomous Path Tracking Steering Controller for Extraterrestrial Terrain Exporation Rover

    Science.gov (United States)

    Ahmed, Mohammed; Sonsalla, Roland; Kirchner, Frank

    Extraterrestrial surface missions typically use a robotic rover platform to carry the science instrumentation (e.g.,the twin MER rovers). Due to the risks in the rover path (i.e. low trafficability of unrecognized soil patches), it is proposed in the FASTER footnote{\\url{https://www.faster-fp7-space.eu}} project that two rovers should be used. A micro scout rover is used for determining the traversability of the terrain and collaborate with a primary rover to lower the risk of entering hazardous areas. That will improve the mission safety and the effective traverse speed for planetary rover exploration. This paper presents the design and implementation of the path following controller for micro scout rover. The objective to synthesize a control law which allows the rover to autonomously follow a desired path in a stable manner. Furthermore, the software architecture controlling the rover and all its subsystems is depicted. The performance of the designed controller is discussed and demonstrated with realistic simulations and experiments, conclusions and an outlook of future work are also given. Key words: Micro Rover, Scout Rover, Mars Exploration, Multi-Rover Team, Mobile, All-Terrain, Hybrid-Legged Wheel, Path Following, Automatic Steer, nonlinear systems.

  17. Harbour seals (Phoca vitulina) can steer by the stars.

    Science.gov (United States)

    Mauck, Björn; Gläser, Nele; Schlosser, Wolfhard; Dehnhardt, Guido

    2008-10-01

    Offshore orientation in marine mammals is still a mystery. For visual orientation during night-time foraging and travelling in the open seas, seals cannot rely on distant terrestrial landmarks, and thus might use celestial cues as repeatedly shown for nocturnally migrating birds. Although seals detect enough stars to probably allow for astronavigation, it was unclear whether they can orient by the night sky. The widely accepted cognitive mechanism for bird night-time orientation by celestial cues is a time-independent star compass with learned geometrical star configurations used to pinpoint north as the rotational centre of the starry sky while there is no conclusive evidence for a time-compensated star compass or true star navigation. Here, we present results for two harbour seals orienting in a custom made swimming planetarium. Both seals learned to highly accurately identify a lodestar out of a pseudo-randomly oriented, realistic projection of the northern hemisphere night sky. Providing the first evidence for star orientation capability in a marine mammal, our seals' outstanding directional precision would allow them to steer by following lodestars of learned star courses, a celestial orientation mechanism that has been known to be used by Polynesian navigators but has not been considered for animals yet.

  18. Effects of beam steering in pulsed-wave ultrasound velocity estimation.

    Science.gov (United States)

    Steinman, Aaron H; Yu, Alfred C H; Johnston, K Wayne; Cobbold, Richard S C

    2005-08-01

    Experimental and computer simulation methods have been used to investigate the significance of beam steering as a potential source of error in pulsed-wave flow velocity estimation. By simulating a typical linear-array transducer system as used for spectral flow estimation, it is shown that beam steering can cause an angle offset resulting in a change in the effective beam-flow angle. This offset primarily depends on the F-number and the nominal steering angle. For example, at an F-number of 3 and a beam-flow angle of 70 degrees , the velocity error changed from -5% to + 5% when the steering angle changed from -20 degrees to + 20 degrees . Much higher errors can occur at higher beam-flow angles, with smaller F-numbers and greater steering. Our experimental study used a clinical ultrasound system, a tissue-mimicking phantom and a pulsatile waveform to determine peak flow velocity errors for various steering and beam-flow angles. These errors were found to be consistent with our simulation results.

  19. Robust H2/H∞ Control for the Electrohydraulic Steering System of a Four-Wheel Vehicle

    Directory of Open Access Journals (Sweden)

    Min Ye

    2014-01-01

    Full Text Available To shorten the steer diameter and to improve the maneuverability flexibility of a construction vehicle, four wheels’ steering system is presented. This steering system consists of mechanical-electrical-hydraulic assemblies. Its diagram and principle are depicted in detail. Then the mathematical models are derived step by step, including the whole vehicle model and the hydraulic route model. Considering the nonlinear and time-varying uncertainty of the steering system, robust H2/H∞ controller is put forward to guarantee both the system performance and the robust stability. The H∞ norm of the sensitive function from the parameter perturbation of the hydraulic system to the yaw velocity of the vehicle is taken as the evaluating index of the robustness and the H2 norm of the transfer function from the external disturbance to the steering angle of the wheel as the index of linear quadratic Gaussian. The experimental results showed that the proposed scheme was superior to classical PID controller and can guarantee both the control performance and the robustness of the steering system.

  20. Numerical research of hydrodynamic performance of hybrid CRP podded propulsor in steering conditions

    Directory of Open Access Journals (Sweden)

    XU Jiaqi

    2017-03-01

    Full Text Available In order to study the influence of steering conditions to hybrid CRP podded propulsor,the calculation of the NACA0012 open-water rudder's lift coefficient was carried out by applying the RANS method combined with the SST k-ω turbulence model, and the near wall mesh arrangement and near wall treatment method applied in numerical calculation were selected through comparisons between the experimental results and the calculation results. The hydrodynamic performance of a podded propulsor was predicted on the basis of the above, and the calculation results showed a good agreement with the experimental results. The object of the research was a hybrid CRP podded propulsor, and its hydrodynamic performance in steering conditions was predicted by applying the numerical method above. Conclusions were drawn on the relationship between hydrodynamic performance parameters and steering angle, i.e. larger magnitudes of the after propeller thrust, pod horizontal force and steering moment will be acquired at larger steering angles, and the fore propeller thrust is basically as invariant as the pod steering. The internal reasons were also analyzed. Research shows that the propeller has good maneuverability,and will have wide application prospect.

  1. Need for airbag and seatbelt to reduce orbital injuries from steering wheel knob.

    Science.gov (United States)

    Hwang, Kun; Kim, Joo Ho

    2014-11-01

    The aims of this study are to report a blowout fracture of the orbital floor and medial wall caused by being struck by a steering wheel knob of an automobile and to discuss the use of airbags and seatbelts as a preventive measure for orbital injuries. A 58-year-old man was struck in the left eye by a steering wheel. His car hit a telephone pole, and he had a frontal collision injury. In this frontal impact, his left eye was hit by a Brodie knob attached to the steering wheel. At the time of injury, the speed of the car was about 65 km/h. He was not wearing a seatbelt, and the airbag had not deployed. Swelling and ecchymosis were observed at the left periorbital area, and he had diplopia on a left-side gaze. A CT revealed fractures in the medial and inferior wall of the left orbit. Entrapped soft tissues were reduced, and the medial wall and floor were reconstructed with a resorbable sheet. His diplopia disappeared 12 days after surgery. To prevent the injury from the steering wheel knob, an airbag should be installed in any vehicle, which has a steering wheel knob. Legislation mandating the use of airbags as well as seatbelts in vehicles with attached steering wheel knobs should be made.

  2. Adaptive Sliding Mode Control Method Based on Nonlinear Integral Sliding Surface for Agricultural Vehicle Steering Control

    Directory of Open Access Journals (Sweden)

    Taochang Li

    2014-01-01

    Full Text Available Automatic steering control is the key factor and essential condition in the realization of the automatic navigation control of agricultural vehicles. In order to get satisfactory steering control performance, an adaptive sliding mode control method based on a nonlinear integral sliding surface is proposed in this paper for agricultural vehicle steering control. First, the vehicle steering system is modeled as a second-order mathematic model; the system uncertainties and unmodeled dynamics as well as the external disturbances are regarded as the equivalent disturbances satisfying a certain boundary. Second, a transient process of the desired system response is constructed in each navigation control period. Based on the transient process, a nonlinear integral sliding surface is designed. Then the corresponding sliding mode control law is proposed to guarantee the fast response characteristics with no overshoot in the closed-loop steering control system. Meanwhile, the switching gain of sliding mode control is adaptively adjusted to alleviate the control input chattering by using the fuzzy control method. Finally, the effectiveness and the superiority of the proposed method are verified by a series of simulation and actual steering control experiments.

  3. On Optimizing Steering Performance of Multi-axle Vehicle Based on Driving Force Control

    Directory of Open Access Journals (Sweden)

    Wu Zhicheng

    2017-01-01

    Full Text Available The steering performance of multi-axle vehicle with independent driving system is affected by the distribution of the wheel driving force. A nonlinear vehicle dynamics model including magic formula tire model for describing 11 DoF four-axle vehicle with dual-front-axle-steering (DFAS system was presented. The influence of different driving force distribution scheme on the steering performance of the vehicle was analyzed. A control strategy for improving the steady response and transient response of the vehicle steering is proposed. The results show: For the steady response, setting different drive force for internal and external wheels according to the actual steering characteristics of the vehicle can effectively improve its steering characteristics; For the transient response, adopting the zero sideslip angle control strategy and using the PID control algorithm to control the driving force of the outside wheel of tear-two-axle, under angle step input, the vehicle sideslip angle can quickly stabilize to 0 and yaw rate also significantly decreases.

  4. Revisiting the steering principal of tropical cyclone motion in a numerical experiment

    Science.gov (United States)

    Wu, Liguang; Chen, Xiaoyu

    2016-12-01

    The steering principle of tropical cyclone motion has been applied to tropical cyclone forecasting and research for nearly 100 years. Two fundamental questions remain unanswered. One is why the steering flow plays a dominant role in tropical cyclone motion, and the other is when tropical cyclone motion deviates considerably from the steering. A high-resolution numerical experiment was conducted with the tropical cyclone in a typical large-scale monsoon trough over the western North Pacific. The simulated tropical cyclone experiences two eyewall replacement processes. Based on the potential vorticity tendency (PVT) diagnostics, this study demonstrates that the conventional steering, which is calculated over a certain radius from the tropical cyclone center in the horizontal and a deep pressure layer in the vertical, plays a dominant role in tropical cyclone motion since the contributions from other processes are largely cancelled out due to the coherent structure of tropical cyclone circulation. Resulting from the asymmetric dynamics of the tropical cyclone inner core, the trochoidal motion around the mean tropical cyclone track cannot be accounted for by the conventional steering. The instantaneous tropical cyclone motion can considerably deviate from the conventional steering that approximately accounts for the combined effect of the contribution of the advection of the symmetric potential vorticity component by the asymmetric flow and the contribution from the advection of the wave-number-one potential vorticity component by the symmetric flow.

  5. Development of the auto-steering software and equipment technology (ASSET)

    Science.gov (United States)

    McKay, Mark D.; Anderson, Matthew O.; Wadsworth, Derek C.

    2003-09-01

    The Idaho National Engineering and Environmental Laboratory (INEEL), through collaboration with INSAT Co., has developed a low cost robotic auto-steering system for parallel contour swathing. The capability to perform parallel contour swathing while minimizing "skip" and "overlap" is a necessity for cost-effective crop management within precision agriculture. Current methods for performing parallel contour swathing consist of using a Differential Global Position System (DGPS) coupled with a light bar system to prompt an operator where to steer. The complexity of operating heavy equipment, ensuring proper chemical mixture and application, and steering to a light bar indicator can be overwhelming to an operator. To simplify these tasks, an inexpensive robotic steering system has been developed and tested on several farming implements. This development leveraged research conducted by the INEEL and Utah State University. The INEEL-INSAT Auto-Steering Software and Equipment Technology provides the following: 1) the ability to drive in a straight line within +/- 2 feet while traveling at least 15 mph, 2) interfaces to a Real Time Kinematic (RTK) DGPS and sub-meter DGPS, 3) safety features such as Emergency-stop, steering wheel deactivation, computer watchdog deactivation, etc., and 4) a low-cost, field-ready system that is easily adapted to other systems.

  6. Carcass characteristics and sensorial evaluation of meat from Nellore steers and crossbred Angus vs. Nellore bulls

    Directory of Open Access Journals (Sweden)

    Vinicius Cunha Barcellos

    2017-09-01

    Full Text Available This study evaluated animal performance, carcass characteristics and meat quality of 36-month old Nellore steers finished in pastures (n = 10 and 20-month old Angus vs. Nellore bulls finished in feedlot (n = 10. Final body weight, carcass weight, characteristics, conformation and fat thickness, were higher (p 0.05 throughout the ageing period for the Angus vs. Nellore bulls, but higher in meat from the Nellore steers (p 0.05 on meat a* value (redness. Likewise, ageing time had no effect on a* in both genetic groups, and genetic group had no effect (p > 0.05 on meat b* value (yellowness. On the other hand, b* was increased after day 7 of ageing for the bulls from the two genetic groups. Thawing and cooking losses were lower for Nellore steers after day 7 of aging (p 0.05 on lipid oxidation; however, lipid oxidation increased after day7. Meat from Nellore steers contained a higher percentage of saturated fatty acids (SFA, a lower percentage of unsaturated (UFA and monounsaturated fatty acids (MUFA and a similar percentage of polyunsaturated fatty acids (PUFA than the meat from Angus vs. Nellore bulls. Intramuscular fat from Nellore steers had a more favourable n-6:n-3 fatty acid ratio than that from Angus vs. Nellore bulls (4.37 vs. 11.45, respectively. Tenderness, flavour and overall acceptability were higher (p < 0.001 for meats of the Nellore steers, regardless of ageing time (1, 4, 7 and 14 days.

  7. Tongue-driven sonar beam steering by a lingual-echolocating fruit bat.

    Science.gov (United States)

    Lee, Wu-Jung; Falk, Benjamin; Chiu, Chen; Krishnan, Anand; Arbour, Jessica H; Moss, Cynthia F

    2017-12-01

    Animals enhance sensory acquisition from a specific direction by movements of head, ears, or eyes. As active sensing animals, echolocating bats also aim their directional sonar beam to selectively "illuminate" a confined volume of space, facilitating efficient information processing by reducing echo interference and clutter. Such sonar beam control is generally achieved by head movements or shape changes of the sound-emitting mouth or nose. However, lingual-echolocating Egyptian fruit bats, Rousettus aegyptiacus, which produce sound by clicking their tongue, can dramatically change beam direction at very short temporal intervals without visible morphological changes. The mechanism supporting this capability has remained a mystery. Here, we measured signals from free-flying Egyptian fruit bats and discovered a systematic angular sweep of beam focus across increasing frequency. This unusual signal structure has not been observed in other animals and cannot be explained by the conventional and widely-used "piston model" that describes the emission pattern of other bat species. Through modeling, we show that the observed beam features can be captured by an array of tongue-driven sound sources located along the side of the mouth, and that the sonar beam direction can be steered parsimoniously by inducing changes to the pattern of phase differences through moving tongue location. The effects are broadly similar to those found in a phased array-an engineering design widely found in human-made sonar systems that enables beam direction changes without changes in the physical transducer assembly. Our study reveals an intriguing parallel between biology and human engineering in solving problems in fundamentally similar ways.

  8. Tongue-driven sonar beam steering by a lingual-echolocating fruit bat.

    Directory of Open Access Journals (Sweden)

    Wu-Jung Lee

    2017-12-01

    Full Text Available Animals enhance sensory acquisition from a specific direction by movements of head, ears, or eyes. As active sensing animals, echolocating bats also aim their directional sonar beam to selectively "illuminate" a confined volume of space, facilitating efficient information processing by reducing echo interference and clutter. Such sonar beam control is generally achieved by head movements or shape changes of the sound-emitting mouth or nose. However, lingual-echolocating Egyptian fruit bats, Rousettus aegyptiacus, which produce sound by clicking their tongue, can dramatically change beam direction at very short temporal intervals without visible morphological changes. The mechanism supporting this capability has remained a mystery. Here, we measured signals from free-flying Egyptian fruit bats and discovered a systematic angular sweep of beam focus across increasing frequency. This unusual signal structure has not been observed in other animals and cannot be explained by the conventional and widely-used "piston model" that describes the emission pattern of other bat species. Through modeling, we show that the observed beam features can be captured by an array of tongue-driven sound sources located along the side of the mouth, and that the sonar beam direction can be steered parsimoniously by inducing changes to the pattern of phase differences through moving tongue location. The effects are broadly similar to those found in a phased array-an engineering design widely found in human-made sonar systems that enables beam direction changes without changes in the physical transducer assembly. Our study reveals an intriguing parallel between biology and human engineering in solving problems in fundamentally similar ways.

  9. Expert and novice facilitated modelling

    DEFF Research Database (Denmark)

    Tavella, Elena; Papadopoulos, Thanos

    2015-01-01

    the behaviour of one expert and two novice facilitators during a Viable System Model workshop. The findings suggest common facilitation patterns in the behaviour of experts and novices. This contrasts literature claiming that experts and novices behave and use their available knowledge differently......This paper provides an empirical study based on action research in which expert and novice facilitators in facilitated modelling workshops are compared. There is limited empirical research analysing the differences between expert and novice facilitators. Aiming to address this gap we study...... and facilitation strategies in contexts in which external, expert facilitation is not always possible are also discussed, and limitations of this study are provided....

  10. Essence: Facilitating Software Innovation

    DEFF Research Database (Denmark)

    Aaen, Ivan

    2008-01-01

      This paper suggests ways to facilitate creativity and innovation in software development. The paper applies four perspectives – Product, Project, Process, and People –to identify an outlook for software innovation. The paper then describes a new facility–Software Innovation Research Lab (SIRL......) – and a new method concept for software innovation – Essence – based on views, modes, and team roles. Finally, the paper reports from an early experiment using SIRL and Essence and identifies further research....

  11. High dietary sulfur decreases the retention of copper, manganese, and zinc in steers.

    Science.gov (United States)

    Pogge, D J; Drewnoski, M E; Hansen, S L

    2014-05-01

    To examine the effects of dietary S on diet digestibility and apparent mineral absorption and retention, 16 steers [8 ruminally fistulated (368 ± 12 kg BW) and 8 unmodified (388 ± 10 kg BW)] were paired within modification status and BW, and within each of the 2 consecutive 28-d periods, 4 pairs of steers were randomly assigned to either a low-S (0.24%) or high-S (0.68%) pelleted diet. Bromegrass hay was fed at 5 or 7% of the diet, during periods 1 and 2, respectively. Sodium sulfate was used to increase the S content of the high-S diet. The low-S steers were fed the amount of feed their high-S counterpart consumed the previous day, while the high-S steers received 110% of the previous day's intake. Steers were adapted to individual metabolism stalls for 4 d (d -3 to 0 of period), acclimated to diet for 7 d (d 1 to 7 of period), and after high-S steers were consuming ad libitum intake for 7 d (d 14 of period), total urine and feces were collected for 5 d. Feed intake and orts were recorded daily. Dry matter and OM digestibility were determined. Jugular blood was collected before and after each collection period on d 14 and 20, and liver biopsies were collected on d 0 and 27. Macromineral (Ca, K, Mg, and Na) and micromineral (Cu, Mn, and Zn) concentrations were determined for pellets and hay, orts, feces, urine, and plasma and liver samples from each steer via inductively coupled plasma spectrometry. Dry matter intake, DM and OM digestibility, and urine volume were not affected (P ≥ 0.11) by dietary treatment, but fecal output was greater (P = 0.02) in the low-S steers than the high-S steers. A high-S diet decreased plasma Cu (P = 0.04) and liver Zn (P = 0.03) compared to low-S steers. No differences (P ≥ 0.20) were noted among urinary excretion of Cu, Mn, and Zn. Sodium absorption was greater (P consumption of a high-S diet for 28 d had limited effects on Ca, K, Mg, and Na absorption and retention, but decreased Cu, Mn, and Zn retention, which may limit

  12. Performance of Beef Steers Fed Brewers Grain Ensiled With Hay or Forage

    International Nuclear Information System (INIS)

    Irungu, K.R.G.; Keingatti, R.K.; Abate, A.N.

    1999-01-01

    yearling Boran beef steers were fed on brewers grain ensiled with Rhodes grass hay or sorghum silage to assess steer nutrient intake, growth and fed conversion efficiency. Forage sorghum variety 'E6518' harvested at grain milk growth stage produced young sorghum silage while that harvested beyond had dough stage made old sorghum silage. At ensiling, brewers grain was mixed with hay, young or old sorghum at ratio of 60:40, 50:50 and 50:50 to produce silage A, B and C. Thirty Boran Steers were used in the experiment where 10 steers were fed on each of the three types of silage. The initial steer group weight averaged 187.6, 188.6 and 186.2 kg for those on diet A, B and C. The steers ate silage A,B and C for 68 days, the initial 12 days being the adaptation period. The pH of A, B and C were 4.7, 4.6 and 4.7. The mean composition of A, B and C were dry matter, 27.5, 23.2 and 23.4%, organic matter, 91.4, 90.0 and 90.3%, crude protein, 12.1 11.2 and 9.8%, crude fibre,26.5, 24.2 and 25.3%. Steer dry matter intake was 3.1, 4.3 and 4.5 kg on A, B and C. Diet A caused loss in steer weight while B and C produced steady growth. Steers on A lost 243 g daily while those on B and C gained 357 and 371 g daily. Feed efficiency expressed in gain per 100 kg dry matter was negative on A but 8.28 and 8.30 kg on B and C. The steer growth rates are similar to cattle grazed on improved ley or fodder and fed a limited amount of concentrates. The three types of silage required protein supplementation to increase growth

  13. Car Gestures - Advisory warning using additional steering wheel angles.

    Science.gov (United States)

    Maag, Christian; Schneider, Norbert; Lübbeke, Thomas; Weisswange, Thomas H; Goerick, Christian

    2015-10-01

    Advisory warning systems (AWS) notify the driver about upcoming hazards. This is in contrast to the majority of currently deployed advanced driver assistance systems (ADAS) that manage emergency situations. The target of this study is to investigate the effectiveness, acceptance, and controllability of a specific kind of AWS that uses the haptic information channel for warning the driver. This could be beneficial, as alternatives for using the visual modality can help to reduce the risk of visual overload. The driving simulator study (N=24) compared an AWS based on additional steering wheel angle control (Car Gestures) with a visual warning presented in a simulated head-up display (HUD). Both types of warning were activated 3.5s before the hazard object was reached. An additional condition of unassisted driving completed the experimental design. The subjects encountered potential hazards in a variety of urban situations (e.g. a pedestrian standing on the curbs). For the investigated situations, subjective ratings show that a majority of drivers prefer visual warnings over haptic information via gestures. An analysis of driving behavior indicates that both warning approaches guide the vehicle away from the potential hazard. Whereas gestures lead to a faster lateral driving reaction (compared to HUD warnings), the visual warnings result in a greater safety benefit (measured by the minimum distance to the hazard object). A controllability study with gestures in the wrong direction (i.e. leading toward the hazard object) shows that drivers are able to cope with wrong haptic warnings and safety is not reduced compared to unassisted driving as well as compared to (correct) haptic gestures and visual warnings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Wide steering angle microscanner based on curved surface

    Science.gov (United States)

    Sabry, Yasser; Khalil, Diaa; Saadany, Bassam; Bourouina, Tarik

    2013-03-01

    Intensive industrial and academic research is oriented towards the design and fabrication of optical beam steering systems based on MEMS technology. In most of these systems, the scanning is achieved by rotating a flat micromirror around a central axis in which the main challenge is achieving a wide mirror rotation angle. In this work, a novel method of optical beam scanning based on reflection from a curved surface is presented. The scanning occurs when the optical axis of the curved surface is displaced with respect to the optical axis of the incident beam. To overcome the possible deformation of the spot with the scanning angle, the curved surface is designed with a specific aspherical profile. Moreover, the scanning exhibits a more linearized scanning angle-displacement relation than the conventional spherical profile. The presented scanner is fabricated using DRIE technology on an SOI wafer. The curved surface (reflector) is metalized and attached to a comb-drive actuator fabricated in the same lithography step. A single-mode fiber, behaving as a Gaussian beam source, is positioned on the substrate facing the mirror. The reflected optical beam angle and spotsize in the far field is recorded versus the relative shift between the fiber and the curved mirror. The spot size is plotted versus the scanning angle and a scanning spot size uniformity of about +/-10% is obtained for optical deflection angles up to 100 degrees. As the optical beam is propagating parallel to the wafer substrate, a completely integrated laser scanner can be achieved with filters and actuators self-aligned on the same chip that allows low cost and mass production of this important product.

  15. Effect of ractopamine hydrochloride and zilpaterol hydrochloride on cardiac electrophysiologic and hematologic variables in finishing steers.

    Science.gov (United States)

    Frese, Daniel A; Reinhardt, Christopher D; Bartle, Steven J; Rethorst, David N; Bawa, Bhupinder; Thomason, Justin D; Loneragan, Guy H; Thomson, Daniel U

    2016-09-15

    OBJECTIVE To investigate the effects of dietary supplementation with the β-adrenoceptor agonists ractopamine hydrochloride and zilpaterol hydrochloride on ECG and clinicopathologic variables of finishing beef steers. DESIGN Randomized controlled trial. ANIMALS 30 Angus steers. PROCEDURES Steers were grouped by body weight and randomly assigned to receive 1 of 3 diets for 23 days: a diet containing no additive (control diet) or a diet containing ractopamine hydrochloride (300 mg/steer/d) or zilpaterol hydrochloride (8.3 mg/kg [3.8 mg/lb] of feed on a dry-matter basis), beginning on day 0. Steers were instrumented with an ambulatory ECG monitor on days -2, 6, 13, and 23, and continuous recordings were obtained for 72, 24, 24, and 96 hours, respectively. At the time of instrumentation, blood samples were obtained for CBC and serum biochemical and blood lactate analysis. Electrocardiographic recordings were evaluated for mean heart rate and arrhythmia rates. RESULTS Steers fed zilpaterol or ractopamine had greater mean heart rates than those fed the control diet. Mean heart rates were within reference limits for all steers, with the exception of those in the ractopamine group on day 14, in which mean heart rate was high. No differences in arrhythmia rates were identified among the groups, nor were any differences identified when arrhythmias were classified as single, paired, or multiple (> 2) beats. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that dietary supplementation of cattle with ractopamine or zilpaterol at FDA-approved doses had no effect on arrhythmia rates but caused an increase in heart rate that remained within reference limits.

  16. A method of detecting a structure in a field, a method of steering an agricultural vehicle and an agricultural vehicle

    DEFF Research Database (Denmark)

    2011-01-01

    An agricultural vehicle (2) comprises a steering system providing steering signals, said steering system comprising an imaging device (11) for imaging surroundings of the vehicle and an image processing device (13), said steering system operating to provide by means of the imaging device (11......) an image of the field (21), analyse the image to obtain texture information, assign to a plurality of areas of the image probability-values reflecting the likelihood that the respective area relates to a specific structure (12), assume at least one geometric property of said specific structure (12...

  17. Ultra-Wideband, Dual-Polarized, Beam-Steering P-Band Array Antenna

    Science.gov (United States)

    duToit, Cornelis

    2014-01-01

    A dual-polarized, wide-bandwidth (200 MHz for one polarization, 100 MHz for the orthogonal polarization) antenna array at P-band was designed to be driven by NASA's EcoSAR digital beam former. EcoSAR requires two wide P-band antenna arrays mounted on the wings of an aircraft, each capable of steering its main beam up to 35deg off-boresight, allowing the twin radar beams to be steered at angles to the flight path. The science requirements are mainly for dual-polarization capability and a wide bandwidth of operation of up to 200 MHz if possible, but at least 100 MHz with high polarization port isolation and low cross-polarization. The novel design geometry can be scaled with minor modifications up to about four times higher or down to about half the current design frequencies for any application requiring a dual-polarized, wide-bandwidth steerable antenna array. EcoSAR is an airborne interferometric P-band synthetic aperture radar (SAR) research application for studying two- and three-dimensional fine-scale measurements of terrestrial ecosystem structure and biomass, which will ultimately aid in the broader study of the carbon cycle and climate change. The two 2×8 element Pband antenna arrays required by the system will be separated by a baseline of about 25 m, allowing for interferometry measurements. The wide 100-to- 200-MHz bandwidth dual-polarized beams employed will allow the determination of the amount of biomass and even tree height on the ground. To reduce the size of the patches along the boresight dimension in order to fit them into the available space, two techniques were employed. One technique is to add slots along the edges of each patch where the main electric currents are expected to flow, and the other technique is to bend the central part of the patch away from the ground plane. The latter also facilitates higher mechanical rigidity. The high port isolation of more than 40 dB was achieved by employing a highly symmetrical feed mechanism for each

  18. Evaluation of metal matrix composite to replace spheroidal graphite iron for a critical component, steering knuckle

    International Nuclear Information System (INIS)

    Vijayarangan, S.; Rajamanickam, N.; Sivananth, V.

    2013-01-01

    Highlights: ► A FE model is developed to study the suitability of MMC for steering knuckle. ► Structural analysis of steering knuckle is carried out for 12 load cases. ► The cross section of the critical region is optimized using genetic algorithm. ► The life of the MMC (Al-10 wt.% TiC) knuckle is compared before and after optimization. ► MMC material could replace SG iron for automotive steering knuckle. -- Abstract: Steering knuckle is considered as one of the critical component in automotive suspension system. It is subjected to time varying loads during its service life, leading to fatigue failure. Therefore, its design is an important aspect in the product development cycle. Currently, spheroidal graphite (SG) iron is widely used to manufacture steering knuckle in the commercial automobile sector. It has been observed from the knuckle manufacturers that advanced materials and weight reduction are the real need for the current automobile industry. Due to their high strength to weight ratio, Metal Matrix Composites (MMCs) have the potential to meet the demanded design requirements of the automotive industry, compared to conventional materials. In this work, an aluminum alloy reinforced with titanium carbide particulate is suggested as an alternate material in place of existing SG iron. Structural analysis of steering knuckle made of alternate material Al-10 wt.% TiC was performed using commercial code ANSYS. The results of steering knuckle made of MMC (Al-10 wt.% TiC) were compared with that of aluminum alloy and SG iron steering knuckles for its performance based on real time load cases. It is found from this analysis, the knuckle strut region has maximum stress and deflection during its life time. The critical strut region cross section area of knuckle was analyzed and geometrically optimized for minimum bending stress and deflection using genetic algorithm available in MatLab. Since, the knuckle experiences time varying loads, fatigue analysis also

  19. Design of a remote steering antenna for ECRH heating in the stellarator Wendelstein 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Plaum, B., E-mail: plaum@igvp.uni-stuttgart.de [Institut für Grenzflächenverfahrenstechnik und Plasmatechnologie (IGVP), Univ. Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Lechte, C.; Kasparek, W.; Gaiser, S.; Zeitler, A. [Institut für Grenzflächenverfahrenstechnik und Plasmatechnologie (IGVP), Univ. Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Erckmann, V. [Max-Planck-Institut für Plasmaphysik, EURATOM-IPP, D-17491 Greifswald (Germany); Weißgerber, M. [Max-Planck-Institut für Plasmaphysik, EURATOM-IPP, D-85748 Garching (Germany); Bechtold, A. [NTG Neue Technologie GmbH & Co KG, D-63571 Gelnhausen (Germany); Busch, M.; Szcepaniak, B. [Galvano-T electroplating-electroforming GmbH, D-51570 Windeck-Rosbach (Germany)

    2015-10-15

    Highlights: • We report about the design activities for the remote steering antennas for the stellarator W7-X. • The integration into the W7-X system and the manufacturing procedure are described. • Simulations and loss measurements for the waveguide walls were done and are in good agreement. • A method for extending the steering range is presented. • A mechanical deformation analysis showed that the deformation is not critical for the beam quality. - Abstract: For the ECRH heating system of the stellarator Wendelstein 7-X, two remote steering antennas are developed and manufactured. The principle of remote steering antennas is based on the imaging characteristics of corrugated rectangular waveguides, which is well understood and can accurately be simulated. Several details, however, require deeper investigation. The antenna needs a miter-bend and a 24 mm gap. The positions of these elements need to be chosen carefully to reduce losses and stray radiation. The antennas are manufactured from copper by electroforming. This allows to integrate all components, including the corrugated inner walls and the cooling channels, in one vacuum-tight piece. This paper reviews the design process of the remote steering antennas for W7-X as well as technological issues and experimental results from test pieces.

  20. Static load simulation of steering knuckle for a formula student race car

    Science.gov (United States)

    Saputro, Bagus Aulia; Ubaidillah, Triono, Dicky Agus; Pratama, Dzaky Roja; Cahyono, Sukmaji Indro; Imaduddin, Fitrian

    2018-02-01

    This research aims to determine the stress distribution which occurs on the steering knuckle and to define its safety factor number. Steering knuckle is the most critical part of a car's steering system. Steering knuckle supports the tie rod, brake caliper, and the wheels to provide stability. Steering knuckle withstands the load which given on the front wheels and functions as the wheel's axis. Balljoint and king support the rotation of the suspension arm. When the car is in idle position, knuckle hold the weight of the car, it gets braking force when it's braking and cornering. Knuckle is designed to have the strength that could withstand load and to have a good safety factor value. Knuckle is designed using Fusion software then simulated using Fusion simulation software with a static load, moment braking force, and cornering force as the loads in this simulation. The simulation works in ideal condition. The result of this simulation is satisfying. This simulation produces a maximum displacement of 0.01281mm, the maximum shear stress is 3.707 MPa on the stub hole, and the safety factor is 5.24. The material used for this product is mild steel AISI 1018.

  1. [Application of ICP-AES in automotive hydraulic power steering system fault diagnosis].

    Science.gov (United States)

    Chen, Li-Dan

    2013-01-01

    The authors studied the innovative applications of the inductively coupled plasma-atomic emission spectrometry in automotive hydraulic power steering system fault diagnosis. After having determined Fe, Cu and Al content in the four groups of Buick Regal 2.4 main metal power-steering fluid whose travel course was respectively 2-9 thousand kilometers, 11-18 thousand kilometers, 22-29 thousandkilometers, and 31-40 thousand kilometers, and the database of primary metal content in the Buick Regal 2.4 different mileage power-steering fluid was established. The research discovered that the main metal content increased with increasing mileage and its normal level is between the two trend lines. Determination of the power-steering fluid main metal content and comparison with its database value can not only judge the wear condition of the automotive hydraulic power steering system and maintain timely to avoid the traffic accident, but also help the automobile detection and maintenance personnel to diagnose failure reasons without disintegration. This reduced vehicle maintenance costs, and improved service quality.

  2. Semi-Automated Needle Steering in Biological Tissue Using an Ultrasound-Based Deflection Predictor.

    Science.gov (United States)

    Khadem, Mohsen; Rossa, Carlos; Usmani, Nawaid; Sloboda, Ron S; Tavakoli, Mahdi

    2017-04-01

    The performance of needle-based interventions depends on the accuracy of needle tip positioning. Here, a novel needle steering strategy is proposed that enhances accuracy of needle steering. In our approach the surgeon is in charge of needle insertion to ensure the safety of operation, while the needle tip bevel location is robotically controlled to minimize the targeting error. The system has two main components: (1) a real-time predictor for estimating future needle deflection as it is steered inside soft tissue, and (2) an online motion planner that calculates control decisions and steers the needle toward the target by iterative optimization of the needle deflection predictions. The predictor uses the ultrasound-based curvature information to estimate the needle deflection. Given the specification of anatomical obstacles and a target from preoperative images, the motion planner uses the deflection predictions to estimate control actions, i.e., the depth(s) at which the needle should be rotated to reach the target. Ex-vivo needle insertions are performed with and without obstacle to validate our approach. The results demonstrate the needle steering strategy guides the needle to the targets with a maximum error of 1.22 mm.

  3. Event-related alpha perturbations related to the scaling of steering wheel corrections.

    Science.gov (United States)

    Brooks, Justin; Kerick, Scott

    2015-10-01

    Previously we derived a new measure relating the driver's steering wheel responses to the vehicle's heading error velocity. This measure, the relative steering wheel compensation (RSWC), changes at times coincident with an alerting stimulus, possibly representing shifts in control strategy as measured by a change in the gain between visual input and motor output. In the present study, we sought to further validate this novel measure by determining the relationship between the RSWC and electroencephalogram (EEG) activity in brain regions associated with sensorimotor transformation processes. These areas have been shown to exhibit event-related spectral perturbation (ERSP) in the alpha frequency band that occurs with the onset of corrective steering wheel maneuvers in response to vehicle perturbations. We hypothesized that these regions would show differential alpha activity depending on whether the RSWC was high or low, reflecting changes in gain between visual input and motor output. Interestingly, we find that low RSWC is associated with significantly less peak desynchronization than larger RSWC. In addition we demonstrate that these differences are not attributable to the amount the steering wheel is turned nor the heading error velocity independently. Collectively these results suggest that neural activity in these sensorimotor regions scales with alertness and may represent differential utilization of multisensory information to control the steering wheel. Published by Elsevier Inc.

  4. Networked Control System for the Guidance of a Four-Wheel Steering Agricultural Robotic Platform

    Directory of Open Access Journals (Sweden)

    Eduardo Paciência Godoy

    2012-01-01

    Full Text Available A current trend in the agricultural area is the development of mobile robots and autonomous vehicles for precision agriculture (PA. One of the major challenges in the design of these robots is the development of the electronic architecture for the control of the devices. In a joint project among research institutions and a private company in Brazil a multifunctional robotic platform for information acquisition in PA is being designed. This platform has as main characteristics four-wheel propulsion and independent steering, adjustable width, span of 1,80 m in height, diesel engine, hydraulic system, and a CAN-based networked control system (NCS. This paper presents a NCS solution for the platform guidance by the four-wheel hydraulic steering distributed control. The control strategy, centered on the robot manipulators control theory, is based on the difference between the desired and actual position and considering the angular speed of the wheels. The results demonstrate that the NCS was simple and efficient, providing suitable steering performance for the platform guidance. Even though the simplicity of the NCS solution developed, it also overcame some verified control challenges in the robot guidance system design such as the hydraulic system delay, nonlinearities in the steering actuators, and inertia in the steering system due the friction of different terrains.

  5. A Steering Model of Endothelial Sheet Migration Recapitulates Monolayer Integrity and Directed Collective Migration ▿ †

    Science.gov (United States)

    Vitorino, Philip; Hammer, Mark; Kim, Jongmin; Meyer, Tobias

    2011-01-01

    Cells in endothelial cell monolayers maintain a tight barrier between blood and tissue, but it is not well understood how endothelial cells move within monolayers, pass each other, migrate when stimulated with growth factor, and also retain monolayer integrity. Here, we develop a quantitative steering model based on functional classes of genes identified previously in a small interfering RNA (siRNA) screen to explain how cells locally coordinate their movement to maintain monolayer integrity and collectively migrate in response to growth factor. In the model, cells autonomously migrate within the monolayer and turn in response to mechanical cues resulting from adhesive, drag, repulsive, and directed steering interactions with neighboring cells. We show that lateral-drag steering explains the local coordination of cell movement and the maintenance of monolayer integrity by allowing closure of small lesions. We further demonstrate that directional steering of cells at monolayer boundaries, combined with adhesive steering of cells behind, can explain growth factor-triggered collective migration into open space. Together, this model provides a mechanistic explanation for the observed genetic modularity and a conceptual framework for how cells can dynamically maintain sheet integrity and undergo collective directed migration. PMID:20974808

  6. Einstein-Podolsky-Rosen-steering swapping between two Gaussian multipartite entangled states

    Science.gov (United States)

    Wang, Meihong; Qin, Zhongzhong; Wang, Yu; Su, Xiaolong

    2017-08-01

    Multipartite Einstein-Podolsky-Rosen (EPR) steering is a useful quantum resource for quantum communication in quantum networks. It has potential applications in secure quantum communication, such as one-sided device-independent quantum key distribution and quantum secret sharing. By distributing optical modes of a multipartite entangled state to space-separated quantum nodes, a local quantum network can be established. Based on the existing multipartite EPR steering in a local quantum network, secure quantum communication protocol can be accomplished. In this manuscript, we present swapping schemes for EPR steering between two space-separated Gaussian multipartite entangled states, which can be used to connect two space-separated quantum networks. Two swapping schemes, including the swapping between a tripartite Greenberger-Horne-Zeilinger (GHZ) entangled state and an EPR entangled state and that between two tripartite GHZ entangled states, are analyzed. Various types of EPR steering are presented after the swapping of two space-separated independent multipartite entanglement states without direct interaction, which can be used to implement quantum communication between two quantum networks. The presented schemes provide technical reference for more complicated quantum networks with EPR steering.

  7. A Vehicle Haptic Steering by Wire System Based on High Gain GPI Observers

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Angeles

    2014-01-01

    Full Text Available A vehicle steering by wire (SBW haptic system based on high gain generalized proportional integral (GPI observers is introduced. The observers are considered for the estimation of dynamic perturbations that are present at the tire and steering wheel. To ensure efficient tracking between the commanded steering wheel angle and the tire orientation angle, the estimated perturbations are on line canceled. As to provide a haptic interface with the driver, the estimated dynamic effects at the steering rack are fed back to the steering wheel, yielding a master-slave haptic system with bilateral communication. For implementation purposes few sensors and minimum knowledge of the dynamic model are required, which is a major advantage compared to other approaches. Only position tracking errors are fed back, while all other signals are estimated by the high gain GPI observers. The scheme is robust to uncertainty on the input gain and cancels dynamic perturbation effects such as friction and aligning forces on the tire. Experimental results are presented on a prototype platform.

  8. Facilitative root interactions in intercrops

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Jensen, E.S.

    2005-01-01

    Facilitation takes place when plants ameliorate the environment of their neighbours, and increase their growth and survival. Facilitation occurs in natural ecosystems as well as in agroecosystems. We discuss examples of facilitative root interactions in intercropped agroecosystems; including...... of root architecture, exudation of growth stimulating substances, and biofumigation. Facilitative root interactions are most likely to be of importance in nutrient poor soils and in low-input agroecosystems due to critical interspecific competition for plant growth factors. However, studies from more...

  9. Expanded R&D by Jet-engine-steering Revolution

    Science.gov (United States)

    Gal-Or, Benjamin

    2017-11-01

    Since 1987 [1,2,3,4,5] the global jet engine community is facing the historical fact that jet engine steering is gradually replacing canards and the common, often dangerous and obsolete, aerodynamic-only flight control - a fact that (i) has already affected the defense-industrial complex in the US, Russia, China, Japan, S-Korea and India, (ii) has integrated the traditional jet-engine components R&D with advanced aero-electro-physics, stealth technology, thrust vectoring aerodynamics and material science. Moreover, this military revolution is historically due to expand into the civil transport jets domain, [6,7,8,9]. The historical aim of the JES-Revolution remains the same: Replace the common, stall-spin sensitive canards [6] and Aerodynamic-Only-Obsolete-Flight Control ("AOOF Control"). Invented about 100 years ago for propeller-driven air vehicles, it has already been partially replaced for failure to function in WVR-combat post-stall domain, and for the following reasons: In comparison with complete Tail-Less, Canard-Less, Stealth-JES (Figure 5 and References [1,2,3,4,5,6]), the common AOOF Control increases drag, weight, fuel consumption, complexity, cost, and reduces flight safety, stealth, [Low Detectability] and provides zero post-stall, WVR air combat capability while its CANARDS KILL LD & REDUCE JES. Examples of stealth fighter aircraft that have already replaced canards and AOOF-Control where JES provides at least 64 to 0 KILL-RATIO advantage over AOOF-Controlled conventional fighter aircraft: The U.S. JES F-22 and, apparently, the Russian JES-Su-T-50 & 35S, China 2016-J-31, Indian HAL AMCA & FGFA, Japanese JES IHHI ATD-X, S-Korean JES KF-X. Cf. X-44 in Figure 5. Consequently, the jet engine is no longer defined as providing only brute force forward. Instead, it successfully competes with and wins over the wrong, dominating AOOF-Control, at least as a backup flight control whose sole factual domain is currently a well-established, primary flight

  10. SSRI Facilitated Crack Dancing

    Directory of Open Access Journals (Sweden)

    Ravi Doobay

    2017-01-01

    Full Text Available Choreoathetoid movement secondary to cocaine use is a well-documented phenomenon better known as “crack dancing.” It consists of uncontrolled writhing movements secondary to excess dopamine from cocaine use. We present a 32-year-old male who had been using cocaine for many years and was recently started on paroxetine, a selective serotonin reuptake inhibitor (SSRI for worsening depression four weeks before presentation. He had been doing cocaine every 2 weeks for the last three years and had never “crack danced” before this episode. The authors have conducted a thorough literature review and cited studies that suggest “crack dancing” is associated with excess dopamine. There has never been a documented case report of an SSRI being linked with “crack dancing.” The authors propose that the excess dopaminergic effect of the SSRI lowered the dopamine threshold for “crack dancing.” There is a communication with the Raphe Nucleus and the Substantia Nigra, which explains how the SSRI increases dopamine levels. This is the first documented case of an SSRI facilitating the “crack dance.”

  11. Facilitating post traumatic growth

    Directory of Open Access Journals (Sweden)

    Cox Helen

    2004-07-01

    Full Text Available Abstract Background Whilst negative responses to traumatic injury have been well documented in the literature, there is a small but growing body of work that identifies posttraumatic growth as a salient feature of this experience. We contribute to this discourse by reporting on the experiences of 13 individuals who were traumatically injured, had undergone extensive rehabilitation and were discharged from formal care. All participants were injured through involvement in a motor vehicle accident, with the exception of one, who was injured through falling off the roof of a house. Methods In this qualitative study, we used an audio-taped in-depth interview with each participant as the means of data collection. Interviews were transcribed verbatim and analysed thematically to determine the participants' unique perspectives on the experience of recovery from traumatic injury. In reporting the findings, all participants' were given a pseudonym to assure their anonymity. Results Most participants indicated that their involvement in a traumatic occurrence was a springboard for growth that enabled them to develop new perspectives on life and living. Conclusion There are a number of contributions that health providers may make to the recovery of individuals who have been traumatically injured to assist them to develop new views of vulnerability and strength, make changes in relationships, and facilitate philosophical, physical and spiritual growth.

  12. Throughput-Based Traffic Steering in LTE-Advanced HetNet Deployments

    DEFF Research Database (Denmark)

    Gimenez, Lucas Chavarria; Kovacs, Istvan Z.; Wigard, Jeroen

    2015-01-01

    The objective of this paper is to propose traffic steering solutions that aim at optimizing the end-user throughput. Two different implementations of an active mode throughput-based traffic steering algorithm for Heterogeneous Networks (HetNet) are introduced. One that always forces handover...... of the active users towards the cell offering the highest throughput, and a second scheme that aims at maximizing the systems sum throughput. Results show that the first option brings the best performance at the cost of more than three handovers per user per second for high-load cases. The second option offers...... slightly lower traffic steering gains at a considerably lower cost in terms of number of handovers. The gain in terms of increased average session throughput for the second option equals 32% at low-load, 18% at medium-load, and 7% at high-load conditions. The gain in the fifth percentile user session...

  13. Steering Angle Control of Car for Dubins Path-tracking Using Model Predictive Control

    Science.gov (United States)

    Kusuma Rahma Putri, Dian; Subchan; Asfihani, Tahiyatul

    2018-03-01

    Car as one of transportation is inseparable from technological developments. About ten years, there are a lot of research and development on lane keeping system(LKS) which is a system that automaticaly controls the steering to keep the vehicle especially car always on track. This system can be developed for unmanned cars. Unmanned system car requires navigation, guidance and control which is able to direct the vehicle to move toward the desired path. The guidance system is represented by using Dubins-Path that will be controlled by using Model Predictive Control. The control objective is to keep the car’s movement that represented by dinamic lateral motion model so car can move according to the path appropriately. The simulation control on the four types of trajectories that generate the value for steering angle and steering angle changes are at the specified interval.

  14. The effect of an active steering system on city bus drivers muscle activity.

    Science.gov (United States)

    Ahlström, Christer; Gink Lövgren, Maria; Nilsson, Mats; Willstrand, Tania; Anund, Anna

    2018-02-26

    City bus drivers spend hours driving under time pressure, in congested traffic and in a monotonous sitting position. This leads to unhealthy working conditions, especially in terms of physical and psychological stress. The aim of this study is to investigate if an active steering system can alleviate the musculoskeletal stress involved in manoeuvring a bus. Twenty bus drivers drove a city bus equipped with the Volvo dynamic steering (VDS) support system in real traffic. Steering effort was evaluated with fyography and with a questionnaire. Compared to baseline, VDS significantly reduced the required muscle activity by on average 15 - 25 % while turning, and with up to 68 % in the part of the manoeuvre requiring maximum effort. The bus drivers believed that VDS will help reduce neck and shoulder problems, and they expressed a desire to have VDS installed in their own bus.

  15. Variance and Passivity Constrained Fuzzy Control for Nonlinear Ship Steering Systems with State Multiplicative Noises

    Directory of Open Access Journals (Sweden)

    Wen-Jer Chang

    2013-01-01

    Full Text Available The variance and passivity constrained fuzzy control problem for the nonlinear ship steering systems with state multiplicative noises is investigated. The continuous-time Takagi-Sugeno fuzzy model is used to represent the nonlinear ship steering systems with state multiplicative noises. In order to simultaneously achieve variance, passivity, and stability performances, some sufficient conditions are derived based on the Lyapunov theory. Employing the matrix transformation technique, these sufficient conditions can be expressed in terms of linear matrix inequalities. By solving the corresponding linear matrix inequality conditions, a parallel distributed compensation based fuzzy controller can be obtained to guarantee the stability of the closed-loop nonlinear ship steering systems subject to variance and passivity performance constraints. Finally, a numerical simulation example is provided to illustrate the usefulness and applicability of the proposed multiple performance constrained fuzzy control method.

  16. Research on optimal driver steering model based on Multi-Point preview

    Science.gov (United States)

    Gu, Jun; Ma, Aijing

    2017-08-01

    In this paper, multi-point preview control algorithm is applied to driver steering control model. This paper builds multi-point preview road model in the form of state shift register. Based on the linear quadratic regulator (LQR) optimal control theory it optimizes driver steering control model with multi-point preview. Meanwhile, in the Matlab Simulink environment, based on vehicle system dynamics and optimal control theory, different preview points and weighted coefficients are simulated to study the influence of driver steering model. The simulation results show that the multi-point preview control mode has excellent driving performance. And in this paper, the main parameters affecting the preview control algorithm such as speed, preview weighted coefficients and the number of preview points and so on are discussed.

  17. Arbitrary vehicle steering characteristics with changing ratio rack and pinion transmission

    Directory of Open Access Journals (Sweden)

    András G Bendefy

    2015-12-01

    Full Text Available In order to achieve arbitrary steering characteristics at vehicles, a steering mechanism was developed, in which changing ratio rack and pinion connections have been applied. In contrary to a regular steering mechanism where only a single rack is used, two racks were applied in order to make arbitrary characteristics possible. The turning wheel’s required motion functions had to be defined first, thereafter could we determine the changing ratio rack and pinion geometry which produces this motion. First, a simplified two-dimensional mockup was created in order to study the difficulties and possibilities of a real construction. Later, a fully functional assembly was designed and manufactured to make further experiments possible.

  18. Fabrication of solar beam steering electrowetting devices—present status and future prospects

    Science.gov (United States)

    Khan, I.; Castelletto, S.; Rosengarten, G.

    2017-10-01

    Many different technologies are used to track the movement of the sun to both enable concentration of its energy and maximize the yearly energy capture. Their present main limitations are the cost, size, visual impact and wind loading, particularly for applications involving mounting to a building. A parabolic concentrator, for example, along with its steering equipment is heavy and bulky, and is not suitable for rooftop applications. Instead, thin and flat solar concentration devices are required for hassle-free rooftop applications. The use of electrowetting-controlled liquid lenses has emerged as a novel approach for solar tracking and concentration. By steering sunlight using thin electrowetting cell arrays, bulky mechanical equipment is not required. The basic concept of this technology is to change the shape of a liquid interface that is formed by two immiscible fluids of different refractive indices, by simply applying an electric field. An important challenge in electrowetting beam steering devices is the optimization of the design and fabrication process for each of their main constituent components, to maximize optical efficiency. In this paper, we report on the state-of-the-art fabrication methods for electrowetting devices for solar beam steering. We have reviewed the present status of different components types and related fabrication methods, and how they affect the efficiency and performance of such devices. The work identifies future prospects in using electrowetting beam steering devices for solar energy applications. This paper will help researchers and developers in the field to determine the components and fabrication process that affect the development of efficient beam steering electrowetting devices.

  19. Dietary zilpaterol hydrochloride. I. Feedlot performance and carcass traits of steers and heifers.

    Science.gov (United States)

    Montgomery, J L; Krehbiel, C R; Cranston, J J; Yates, D A; Hutcheson, J P; Nichols, W T; Streeter, M N; Bechtol, D T; Johnson, E; TerHune, T; Montgomery, T H

    2009-04-01

    Experiments were conducted at 3 US locations (CA, ID, and TX) to determine the effects of dietary zilpaterol hydrochloride (Zilmax, Intervet Inc., Millsboro, DE) and duration of zilpaterol feeding on performance and carcass merit of finishing steers and heifers. At each site, 160 steers and 160 heifers were stratified within sex by initial BW (study d -1) and assigned randomly within BW strata to 1 of 4 treatments in a randomized complete block design (4 blocks/treatment for each sex). The 4 treatments were arranged in a 2 (no zilpaterol vs. zilpaterol) x 2 (20 or 40 d duration of zilpaterol feeding) factorial arrangement of treatments. When included in the diet, zilpaterol was supplemented at 8.3 mg/kg of DM. Each pen consisted of 10 animals. Each animal was individually weighed unshrunk on d 1, 21 or 41, and 66 of the experiment. Following d 66, cattle were slaughtered and carcass data collected. Feeding zilpaterol increased (Por= 0.12) and KPH (P >or= 0.70) were not affected by feeding zilpaterol to steers or heifers. Feeding zilpaterol decreased (i.e., improved; P=0.02) calculated yield grade of steer and heifer carcasses. Marbling score (P=0.002) and quality grade (P=0.002) were decreased when zilpaterol hydrochloride was fed to steers, and the decrease in marbling score and quality grade tended to be greater when zilpaterol was fed for 40 compared with 20 d (zilpaterol x duration interaction, P=0.07). For heifers, marbling score tended (P=0.07) to be decreased and quality grade was decreased (P=0.05) when zilpaterol hydrochloride was fed. In general, it appears from these data that zilpaterol hydrochloride fed for 20 to 40 d at the end of the finishing period enhances growth performance and carcass muscle deposition for steers and heifers.

  20. Effects of supplementing zinc or chromium to finishing steers fed ractopamine hydrochloride on growth performance, carcass characteristics, and meat quality.

    Science.gov (United States)

    Edenburn, B M; Kneeskern, S G; Bohrer, B M; Rounds, W; Boler, D D; Dilger, A C; Felix, T L

    2016-02-01

    Objectives were to determine the effects of feeding ractopamine hydrochloride (RAC) with zinc (Zn) and chromium (Cr) on feedlot growth performance, carcass characteristics, and meat quality. Steers ( = 179; initial BW = 533 ± 94 kg) were blocked by BW and allotted to 30 pens, and pens were randomly assigned 1 of 5 treatments: (1) control (CONT), (2) RAC only (RO), (3) RAC + Zn (RZ), (4) RAC + Cr (RC), or (5) RAC + Zn + Cr (RZC). Trace minerals were fed from d 0 to 63 to target 1 g of Zn/steer·d (KemTRACE Zn; Kemin Industries, Inc., Des Moines, IA) and 3 mg Cr/steer·d (KemTRACE Chromium; Kemin Industries, Inc.) for Zn and Cr treatments, respectively. Dry-rolled corn, 0.605 kg/steer, was removed from the diet and 400 mg RAC, per 0.605 kg of ground corn carrier, was top dressed per steer immediately following feed delivery to pens fed RAC. There were no effects ( ≥ 0.45) of trace mineral supplementation on DMI, ADG, or G:F before RAC feeding. There were also no treatment effects ( ≥ 0.46) over all 63 d of the trial on DMI, ADG, or G:F. Despite the lack of differences in live performance, steers fed RO and RC averaged 0.10 kg/d greater ( = 0.10) carcass ADG than steers fed RZC and CONT, while steers fed RZ were intermediate and not different. Steers fed RO had the greatest ( = 0.09) carcass G:F, while steers fed CONT had the least carcass G:F, 0.0875 and 0.0774, respectively. Steers fed RO and RC averaged 5.5 kg heavier ( = 0.09) HCW than steers fed RZC and CONT, while steers fed RZ were intermediate and not different. There were no treatment effects ( ≥ 0.32) on LM area, 12th rib fat, marbling score, KPH, carcass yield, or USDA yield grade and distribution. However, carcasses from steers fed RC had the greatest ( = 0.10) percentage grading USDA Select. There were no treatment effects ( ≥ 0.20) on shear force, intramuscular fat, pH, a*, and b*. Steaks from steers fed RO and RC had 11.4% greater ( = 0.08) cook loss than steaks from steers fed CONT and RZC

  1. How to Steer and Lead Educational Processes in a Digital Medium Environment?

    OpenAIRE

    Tække, Jesper

    2015-01-01

    This paper is about challenges to steering and leadership of educational interaction in classrooms provided by the new medium environment that comes with digital media. In the new medium environment, the old way of steering what is going on in the classroom appears not to work any more since it was developed in the image of the industrial society and based on a closed classroom. Now with the digital media and wireless networks the classroom is opened and the old way of organizing teaching has...

  2. Steering population transfer of the Na2 molecule by an ultrashort pulse train

    Science.gov (United States)

    Niu, Dong-Hua; Wang, Shuo; Zhan, Wei-Shen; Tao, Hong-Cai; Wang, Si-Qi

    2018-05-01

    We theoretically investigate the complete population transfer among quantum states of the Na2 molecule using ultrashort pulse trains using the time-dependent wave packet method. The population accumulation of the target state can be steered by controlling the laser parameters, such as the variable pulse pairs, the different pulse widths, the time delays and the repetition period between two contiguous pulses; in particular, the pulse pairs and the pulse widths have a great effect on the population transfer. The calculations show that the ultrashort pulse train is a feasible solution, which can steer the population transfer from the initial state to the target state efficiently with lower peak intensities.

  3. 5G antenna array with wide-angle beam steering and dual linear polarizations

    KAUST Repository

    Klionovski, Kirill

    2017-10-25

    In this paper, we present the design of a switched-beam antenna array at millimeter-wave frequencies for future 5G applications. The proposed antenna array is based on wideband patch antenna elements and a Butler matrix feed network. The patch antenna has a broad radiation pattern for wide-angle beam steering and allows the simultaneous operation with two orthogonal linear polarizations. A combination of two separated Butler matrices provides independent beam steering for both polarizations in the wide operating band. The antenna array has a simple multilayer construction, and it is made on a low-cost Rogers laminate.

  4. System Design for On-line Distributed Computational Visualization and Steering

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qishi [ORNL; Zhu, Mengxia [ORNL; Rao, Nageswara S [ORNL

    2006-01-01

    We propose a distributed computing framework for network-optimized visualization and steering of real-time scientific simulations and computations executed on a remote host, such as workstation, cluster or supercomputer. Unlike the conventional "batch" simulations, this system enables: (i) monitoring of an ongoing remote computation using visualization tools, and (ii) on-line specification of simulation parameters to interactively steer remote computations. Using performance models for transport channels and visualization modules, we develop a dynamic programming method to optimize the realization of the visualization pipeline over a wide-area network to maximize the frame rate. We present experimental results to illustrate the effectiveness of this system.

  5. Helicopter downwash measured by continuous-wave Doppler lidars with agile beam steering

    OpenAIRE

    Sjöholm, Mikael; Angelou, Nikolas; Hansen, Per; Hansen, Kasper Hjorth; Mikkelsen, Torben; Haga, Steinar; Silgjerd, Jon Arne; Starsmore, Neil

    2012-01-01

    A ground-based remote sensing short-range WindScanner with agile beam steering based on a modified ZephIR continuous-wave wind lidar (LIght Detection And Ranging) and a double prism arrangement has recently been developed at the Department of Wind Energy at the DTU Risø campus. The WindScanner measures the line-of-sight component of the wind and by rapid steering of the line-of-sight and the focus position, all locations within a cone with a full top angle of 120 can be reached from about 8 m...

  6. Effects of grazing system on production and parasitism of dairy breed heifers and steers grazing wet marginal grasslands

    DEFF Research Database (Denmark)

    Kristensen, Troels; Thamsborg, S.M.; Andersen, Refsgaard

    2006-01-01

    Production and endoparasitism of first grazing season Holstein heifers and steers were investigated over two grazing seasons. Studies were conducted on low-lying peaty soil. In year 2000, 40 animals were included in a 2x2 factorial, replicated experiment with two sexes (steers v. heifers) and two...

  7. Genetic algorithm–based varying parameter linear quadratic regulator control for four-wheel independent steering vehicle

    Directory of Open Access Journals (Sweden)

    Linlin Gao

    2015-11-01

    Full Text Available From the perspective of vehicle dynamics, the four-wheel independent steering vehicle dynamics stability control method is studied, and a four-wheel independent steering varying parameter linear quadratic regulator control system is proposed with the help of expert control method. In the article, a four-wheel independent steering linear quadratic regulator controller for model following purpose is designed first. Then, by analyzing the four-wheel independent steering vehicle dynamic characteristics and the influence of linear quadratic regulator control parameters on control performance, a linear quadratic regulator control parameter adjustment strategy based on vehicle steering state is proposed to achieve the adaptive adjustment of linear quadratic regulator control parameters. In addition, to further improve the control performance, the proposed varying parameter linear quadratic regulator control system is optimized by genetic algorithm. Finally, simulation studies have been conducted by applying the proposed control system to the 8-degree-of-freedom four-wheel independent steering vehicle dynamics model. The simulation results indicate that the proposed control system has better performance and robustness and can effectively improve the stability and steering safety of the four-wheel independent steering vehicle.

  8. Effects of zilpaterol hydrochloride on methane production, total body oxygen consumption, and blood metabolites in finishing beef steers

    Science.gov (United States)

    An indirect calorimetry experiment was conducted to determine the effects of feeding zilpaterol hydrochloride (ZH) for 20 d on total body oxygen consumption, respiratory quotient, methane production, and blood metabolites in finishing beef steers. Sixteen Angus steers (initial BW = 555 ± 12.7 kg) w...

  9. The effect of sire breed on the melting point and fatty acid composition of subcutaneous fat in steers.

    Science.gov (United States)

    Perry, D; Nicholls, P J; Thompson, J M

    1998-01-01

    Fatty acid composition and the melting point of subcutaneous fat was determined in 18 Hereford, 25 Brahman x Hereford, 22 Simmental x Hereford, and 15 Friesian x Hereford steers that were grown out on pasture at two sites and slaughtered when the mean weight of the Herefords at each site was ca. 450 kg. Multivariate and univariate analyses tested the relations of fatty acid composition, degree of saturation, and melting point with sire breed, environment, age, and carcass characteristics. Hereford and Brahman steers were fatter than the Simmental and Friesian steers. Fat from Brahman-sired steers had a melting point 2.5 degrees C lower than fat from the Bos taurus-sired steers at the same age and had a higher proportion of unsaturated fatty acids, independent of variation in carcass weight and fatness. Melting point and degree of saturation decreased as age increased. Step-down discriminant analyses identified a set of three acids (14:0, 16:0, and 17:1) that differed among sire breeds, independent of differences in melting point: the acids 14:0 and 16:0 discriminated between Brahman and Bos taurus steers and 17:1 between Hereford and Simmental and Friesian steers. Increase in fatness was associated with an increase in 17:1, but, at the same fatness, no acids discriminated among the Bos taurus-sired steers. The use of Bos indicus cattle or their crossbreeds in situations in which hard-setting fat is likely may mitigate the problem.

  10. The influence of Unruh effect on quantum steering for accelerated two-level detectors with different measurements

    Science.gov (United States)

    Liu, Tonghua; Wang, Jieci; Jing, Jiliang; Fan, Heng

    2018-03-01

    We propose a tight measure of quantum steering and study the dynamics of steering in a relativistic setting via different quantifiers. We present the dynamics of steering between two correlated Unruh-Dewitt detectors when one of them locally interacts with external scalar field. We find that the quantum steering, either measured by the entropic steering inequality or the Cavalcanti-Jones-Wiseman-Reid inequality, is fragile under the influence of Unruh thermal noise. The quantum steering is found always asymmetric and the asymmetry is extremely sensitive to the initial state parameter. In addition, the steering-type quantum correlations experience "sudden death" for some accelerations, which are quite different from the behaviors of other quantum correlations in the same system. It is worth noting that the domination value of the tight quantum steering exists a transformation point with increasing acceleration. We also find that the robustness of quantum steerability under the Unruh thermal noise can be realized by choosing the smallest energy gap in the detectors.

  11. Novel Microstrip Patch Antennas with Frequency Agility, Polarization Reconfigurability, Dual Null Steering Capability and Phased Array Antenna with Beam Steering Performance

    Science.gov (United States)

    Babakhani, Behrouz

    Nowadays the wireless communication technology is playing an important role in our daily life. People use wireless devices not only as a conventional communication device but also as tracking and navigation tool, web browsing tool, data storage and transfer tool and so for many other reasons. Based on the user demand, wireless communication engineers try to accommodate as many as possible wireless systems and applications in a single device and therefore, creates a multifunctional device. Antenna, as an integral part of any wireless communication systems, should also be evolved and adjusted with development of wireless transceiver systems. Therefore multifunctional antennas have been introduced to support and enhance the functionality on modern wireless systems. The main focus and contribution of this thesis is design of novel multifunctional microstrip antennas with frequency agility, polarization reconfigurablity, dual null steering capability and phased array antenna with beam steering performance. In this thesis, first, a wide bandwidth(1.10 GHz to 1.60 GHz) right-handed circularly polarized (RHCP) directional antenna for global positioning system (GPS) satellite receive application has been introduced which covers all the GPS bands starting from L1 to L5. This design consists of two crossed bow-tie dipole antennas fed with sequentially phase rotated feed network backed with an artificial high impedance surface (HIS) structure to generate high gain directional radiation patterns. This design shows good CP gain and axial ratio (AR) and wide beamwidth performance. Although this design has good radiation quality, the size and the weight can be reduced as future study. In the second design, a frequency agile antenna was developed which also covers the L-band (L1 to L5) satellite communication frequencies. This frequency agile antenna was designed and realized by new implementation of varactor diodes in the geometry of a circular patch antenna. Beside wide frequency

  12. Near-Infrared and Optical Beam Steering and Frequency Splitting in Air-Holes-in-Silicon Inverse Photonic Crystals

    Science.gov (United States)

    2017-01-01

    We present the design of a dielectric inverse photonic crystal structure that couples line-defect waveguide propagating modes into highly directional beams of controllable directionality. The structure utilizes a triangular lattice made of air holes drilled in an infinitely thick Si slab, and it is designed for operation in the near-infrared and optical regime. The structure operation is based on the excitation and manipulation of dark dielectric surface states, in particular on the tailoring of the dark states’ coupling to outgoing radiation. This coupling is achieved with the use of properly designed external corrugations. The structure adapts and matches modes that travel through the photonic crystal and the free space. Moreover it facilitates the steering of the outgoing waves, is found to generate well-defined, spatially and spectrally isolated beams, and may serve as a frequency splitting component designed for operation in the near-infrared regime and in particular the telecom optical wavelength band. The design complies with the state-of-the-art Si nanofabrication technology and can be directly scaled for operation in the optical regime. PMID:29541653

  13. Effect of essential oils, tylosin, and monensin on finishing steer performance, carcass characteristics, liver abscesses, ruminal fermentation, and digestibility.

    Science.gov (United States)

    Meyer, N F; Erickson, G E; Klopfenstein, T J; Greenquist, M A; Luebbe, M K; Williams, P; Engstrom, M A

    2009-07-01

    A feedlot (Exp. 1) experiment was conducted to evaluate the effects of an essential oil mixture (EOM), experimental essential oil mixture (EXP), tylosin, and monensin (MON) on performance, carcass characteristics, and liver abscesses. A metabolism experiment (Exp. 2) was conducted to evaluate the effects of EOM, EXP, and MON on ruminal fermentation and digestibility in finishing steers. In Exp. 1, 468 yearling steers (398 +/- 34 kg initial BW) were used in 50 pens (10 pens/treatment) and received their respective dietary treatments for 115 d. Five dietary treatments were compared in Exp. 1: 1) control, no additives (CON); 2) EOM, 1.0 g/steer daily; 3) EXP, 1.0 g/steer daily; 4) EOM, 1.0 g/steer daily plus tylosin, 90 mg/steer daily (EOM+T); and 5) monensin, 300 mg/steer daily plus tylosin, 90 mg/steer daily (MON+T). Compared with CON, steers fed MON+T had decreased DMI (P 0.58). There was a trend (P = 0.09) for a treatment effect on 12th-rib fat thickness, which resulted in a significant increase in calculated yield grade for the EOM+T treatment. No other carcass characteristics were affected by treatment (P >/= 0.10). Prevalence of total liver abscesses was reduced for steers fed tylosin compared with no tylosin (P 0.30). Feed intake patterns were similar among feed additive treatments (P > 0.13). Total VFA (P = 0.10) and acetate (P = 0.06) concentrations tended to be affected by treatment with EOM numerically greater than CON. Average ruminal pH ranged from 5.59 to 5.72 and did not differ among treatments. Addition of a EOM or monensin to a diet containing tylosin improves G:F, but little difference was observed in metabolism or digestibility.

  14. Development of a Computational Steering Framework for High Performance Computing Environments on Blue Gene/P Systems

    KAUST Repository

    Danani, Bob K.

    2012-07-01

    Computational steering has revolutionized the traditional workflow in high performance computing (HPC) applications. The standard workflow that consists of preparation of an application’s input, running of a simulation, and visualization of simulation results in a post-processing step is now transformed into a real-time interactive workflow that significantly reduces development and testing time. Computational steering provides the capability to direct or re-direct the progress of a simulation application at run-time. It allows modification of application-defined control parameters at run-time using various user-steering applications. In this project, we propose a computational steering framework for HPC environments that provides an innovative solution and easy-to-use platform, which allows users to connect and interact with running application(s) in real-time. This framework uses RealityGrid as the underlying steering library and adds several enhancements to the library to enable steering support for Blue Gene systems. Included in the scope of this project is the development of a scalable and efficient steering relay server that supports many-to-many connectivity between multiple steered applications and multiple steering clients. Steered applications can range from intermediate simulation and physical modeling applications to complex computational fluid dynamics (CFD) applications or advanced visualization applications. The Blue Gene supercomputer presents special challenges for remote access because the compute nodes reside on private networks. This thesis presents an implemented solution and demonstrates it on representative applications. Thorough implementation details and application enablement steps are also presented in this thesis to encourage direct usage of this framework.

  15. Braking, steering, and wear performance of radial-belted and bias-ply aircraft tires

    Science.gov (United States)

    Yager, Thomas J.; Davis, Pamela A.; Stubbs, Sandy M.; Martinson, Veloria J.

    1992-01-01

    Preliminary steering, braking, and tread wear performance results from testing of radial-belted and bias-ply aircraft tires at NASA Langley are described. An overview of the joint NASA/FAA/industry START program is presented. Attention is given to the Langley Test Facility, equipment and future activities.

  16. Influence of Road Excitation and Steering Wheel Input on Vehicle System Dynamic Responses

    Directory of Open Access Journals (Sweden)

    Zhen-Feng Wang

    2017-06-01

    Full Text Available Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steering wheel input on vehicle roll behavior. Then, a 9 degree of freedom (9-DOF full-car roll nonlinear model including vertical and lateral dynamics was developed to study vehicle roll dynamics with or without of road excitation. Based on a 6-DOF half-car roll model and 9-DOF full-car nonlinear model, relationship between three-dimensional (3-D road excitation and various steering wheel inputs on vehicle roll performance was studied. Finally, an E-Class (SUV level car model in CARSIM® was used, as a benchmark, with and without road input conditions. Both half-car and full-car models were analyzed under steering wheel inputs of 5°, 10° and 15°. Simulation results showed that the half-car model considering road input was found to have a maximum accuracy of 65%. Whereas, the full-car model had a minimum accuracy of 85%, which was significantly higher compared to the half-car model under the same scenario.

  17. International Linear Collider Steering Committee issues charge to Technology Recommendation Panel

    CERN Multimedia

    2003-01-01

    "Following its November 19 meeting in Paris, the International Linear Collider Steering Committee, a subcommittee of the International Committee for Future Accelerators, has published the charge http://www.fnal.gov/directorate/icfa/ITRP_Charge.pdf to the International Technology Recommendation Panel appointed by ICFA" (2 paragraphs).

  18. Enhanced focus steering abilities of multi-element therapeutic arrays operating in nonlinear regimes

    Energy Technology Data Exchange (ETDEWEB)

    Yuldashev, P., E-mail: petr@acs366.phys.msu.ru; Ilyin, S. [Physics Faculty, Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation); Gavrilov, L. [Andreyev Acoustics Institute, 4 Schvernik Str., 117036 Moscow (Russian Federation); Sapozhnikov, O.; Khokhlova, V. [Physics Faculty, Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation); Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, 1013 NE 40" t" h, Street, Seattle, WA 98105 (United States); Kreider, W. [Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, 1013 NE 40" t" h, Street, Seattle, WA 98105 (United States)

    2015-10-28

    Steering abilities of a typical HIFU therapeutic array operated in linear and nonlinear regimes were compared using numerical simulation with the 3D Westervelt equation. The array included 256 elements of 1.2 MHz frequency and 6.6 mm diameter distributed in a quasi-random pattern over a spherical shell with a 130 mm aperture and a focal length of 120 mm. In the case of linear focusing, thermal effects are proportional to the intensity level and the criterion for safe array operation is that the intensity in the grating lobes should be less than 10% of the intensity in the main focus. In the case of nonlinear focusing, the heating effect is no longer proportional to intensity; therefore the heat deposition rate was chosen as the relevant metric, using the same 10% threshold for the secondary lobe in comparison with the focal maximum. When steering the focus, the same linearly predicted intensity level at the main focus was maintained by increasing the array power. Numerical simulations of the acoustic field were performed for nonlinear propagation both in water and in tissue. It was shown that for shock-forming conditions in the main focus, the steering range of safe electronic focusing is larger than that for linear propagation conditions. Nonlinear sonication regimes therefore can be used to enlarge tissue volumes that can be sonicated using electronic steering of the focus of HIFU arrays.

  19. Avoiding Internal Capsule Stimulation With a New Eight-Channel Steering Deep Brain Stimulation Lead

    NARCIS (Netherlands)

    van Dijk, Kees J.; Verhagen, Rens; Bour, Lo J.; Heida, Ciska; Veltink, Peter H.

    2017-01-01

    Objective: Novel deep brain stimulation (DBS) lead designs are currently entering the market, which are hypothesized to provide a way to steer the stimulation field away from neural populations responsible for side effects and towards populations responsible for beneficial effects. The objective of

  20. Avoiding Internal Capsule Stimulation With a New Eight-Channel Steering Deep Brain Stimulation Lead

    NARCIS (Netherlands)

    van Dijk, Kees J.; Verhagen, Rens; Bour, Lo J.; Heida, Ciska; Veltink, Peter H.

    2017-01-01

    Novel deep brain stimulation (DBS) lead designs are currently entering the market, which are hypothesized to provide a way to steer the stimulation field away from neural populations responsible for side effects and towards populations responsible for beneficial effects. The objective of this study

  1. Alteration of fasting heat production during fescue toxicosis in Holstein steers

    Science.gov (United States)

    This study was designed to examine alteration of fasting heat production (FHP) during fescue toxicosis. Six ruminally cannulated Holstein steers (BW=348 ±13 kg) were weight-matched into pairs and utilized in a two period crossover design experiment. Each period consisted of two temperature segments,...

  2. Diesel Technology: Steering and Suspension. Second Edition. Teacher Edition [and] Student Edition.

    Science.gov (United States)

    Miller, Roger; Scarberry, Terry; Tesch, Carl; Kellum, Mary

    These teacher and student editions on steering and suspension are part of the diesel mechanics series of instructional materials. The series aligns with the medium/heavy duty truck task list developed by the National Automotive Technicians Education Foundation and used by the National Institute for Automotive Service Excellence in the…

  3. Educational Leaders' Doctoral Research That Informed Strategies to Steer Their Organizations towards Cultural Alignment

    Science.gov (United States)

    Taysum, Alison

    2016-01-01

    This research generates new knowledge about how 24 educational leaders in the USA and England used their doctoral research to build narrative capital to inform strategies to steer their organizations towards cultural alignment. Cultural alignment prevents forms of segregation rooted in nation-states' wider historiography of education segregation…

  4. Alignment Adjustment Procedures. Automotive Mechanics. Steering & Suspension. Instructor's Guide [and] Student Guide.

    Science.gov (United States)

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automotive steering and suspension, consists of a student guide and an instructor guide dealing with automobile alignment and adjustment procedures. Covered in the module are identifying positive and negative cambers, positive and negative casters, and toe-ins;…

  5. Front-End Types. Automotive Mechanics. Steering & Suspension. Instructor's Guide [and] Student Guide.

    Science.gov (United States)

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automotive steering and suspension, consists of a student guide and an instructor guide dealing with automobile front-end types. Covered in the module are three common types of passenger car front suspension systems and their major components as well as two types…

  6. Pre-Alignment Checks. Automotive Mechanics. Steering & Suspension. Instructor's Guide [and] Student Guide.

    Science.gov (United States)

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automotive steering and suspension, consists of a student guide and an instructor guide dealing with prealignment checks. Covered in the module are the following steps in a prealignment check: checking the ride height of a vehicle, checking the ball joints and the…

  7. A Neural Model of Visually Guided Steering, Obstacle Avoidance, and Route Selection

    Science.gov (United States)

    Elder, David M.; Grossberg, Stephen; Mingolla, Ennio

    2009-01-01

    A neural model is developed to explain how humans can approach a goal object on foot while steering around obstacles to avoid collisions in a cluttered environment. The model uses optic flow from a 3-dimensional virtual reality environment to determine the position of objects on the basis of motion discontinuities and computes heading direction,…

  8. Steering the Union. The Impact of the EU Presidency on Legislative Activity in the Council

    NARCIS (Netherlands)

    Warntjen, Andreas

    2007-01-01

    Their term in office as the Council Presidency offers Member States a unique opportunity to steer the Union’s legislative activity according to their national priorities. This article offers evidence in the field of environmental policy for the period 1984 to 2001.

  9. Beef steers implanted with short, medium and long-acting anabolic ...

    African Journals Online (AJOL)

    On 14November 1984, 150 long yearling Brahman-cross steers were randomly allocated to one of the following five treatments: Type. Length. Hormone ... Cattle were slaughtered in two groups, all those in Experiment 1 in one batch, and those in Experiment 2 in another. During the slaughter process cold carcass masses ...

  10. live and carcass characteristics of bulls and steers castrated at three ...

    African Journals Online (AJOL)

    and following a finishing period on a moderate level of nutrrtion the animals were slaughtered at l2 to l3 months of age. There was a linear decrease in hight at wither's as the age at castration was delayed. The steers castrated at 3 months had the poorest performance throughout the trial. The buLls produced the heaviest ...

  11. Fatty acid composition of beef steers as affected by diet and fat depot

    African Journals Online (AJOL)

    Subcutaneous and perirenal fatty acid (FA) profiles were compared in steers fed a control diet (70 : 30 red clover silage (RC) : barley concentrate), a diet with sunflower seed (SS) substituted for barley, and diets with 15% or 30% wheat dried distillers' grain with solubles (DDGS-15 and DDGS-30) substituted for RC and SS.

  12. Weight gain and behavior of Raramuri Criollo versus Corriente steers developed on Chihuahuan Desert rangeland

    Science.gov (United States)

    Ranchers that raise Criollo cattle must overcome the challenge of lack of markets for weaned calves. Raramuri Criollo (RC) steers are commonly raised for beef and finished on rangelands, while Corriente (CR) are often raised for rodeo sports. No data exist on weight gains and grazing behavior of ran...

  13. Chromium supplementation enhances the metabolic response of steers to lipopolysaccharide (LPS) challenge

    Science.gov (United States)

    The effect of chromium (Cr; KemTRACE®brandChromiumProprionate 0.04%, Kemin Industries) supplementation on the metabolic response to LPS challenge was examined. Steers (n=20; 235±4 kg body weight (BW)) received a premix that added 0 (Con) or 0.2 mg/kg Cr to the total diet (DM (dry matter) basis) for ...

  14. Temporal steering and security of quantum key distribution with mutually unbiased bases against individual attacks

    Czech Academy of Sciences Publication Activity Database

    Bartkiewicz, K.; Černoch, Antonín; Lemr, K.; Miranowicz, A.; Nori, F.

    2016-01-01

    Roč. 93, č. 6 (2016), 1-7, č. článku 062345. ISSN 2469-9926 R&D Projects: GA ČR GAP205/12/0382 Institutional support: RVO:68378271 Keywords : quantum key distribution * Einstein-Podolsky-Rosen steering * temporal quantum correlations Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.925, year: 2016

  15. Multi-Level Steering and Institution Building: The European Union's Approach to Research Policy

    Science.gov (United States)

    Young, Mitchell

    2012-01-01

    Adopting the conception of the university as a primary driver of innovation and economic growth has brought increased pressure for the European Union (EU) to actively steer university-based research policy, despite its being outside of the EU's direct jurisdiction. While the open method of coordination (OMC) was developed for such situations, the…

  16. Ultrasound-guided three-dimensional needle steering in biological tissue with curved surfaces

    NARCIS (Netherlands)

    Abayazid, Momen; Moreira, Pedro; Shahriari, Navid; Patil, Sachin; Alterovitz, Ron; Misra, Sarthak

    In this paper, we present a system capable of automatically steering a bevel-tipped flexible needle under ultrasound guidance toward a physical target while avoiding a physical obstacle embedded in gelatin phantoms and biological tissue with curved surfaces. An ultrasound pre-operative scan is

  17. Angular CMA: A modified Constant Modulus Algorithm providing steering angle updates

    NARCIS (Netherlands)

    Blom, K.C.H.; van de Burgwal, M.D.; Rovers, K.C.; Kokkeler, Andre B.J.; Smit, Gerardus Johannes Maria

    2011-01-01

    Conventional blind beamforming algorithms have no direct notion of the physical Direction of Arrival angle of an impinging signal. These blind adaptive algorithms operate by adjusting the complex steering vector in the case of changing signal conditions and directions. This paper presents Angular

  18. Evaluation of Fatigue Life Reliability of Steering Knuckle Using Pearson Parametric Distribution Model

    Directory of Open Access Journals (Sweden)

    E. A. Azrulhisham

    2010-01-01

    Full Text Available Steering module is a part of automotive suspension system which provides a means for an accurate vehicle placement and stability control. Components such as steering knuckle are subjected to fatigue failures due to cyclic loads arising from various driving conditions. This paper intends to give a description of a method used in the fatigue life reliability evaluation of the knuckle used in a passenger car steering system. An accurate representation of Belgian pave service loads in terms of response-time history signal was obtained from accredited test track using road load data acquisition. The acquired service load data was replicated on durability test rig and the SN method was used to estimate the fatigue life. A Pearson system was developed to evaluate the predicted fatigue life reliability by considering the variations in material properties. Considering random loads experiences by the steering knuckle, it is found that shortest life appears to be in the vertical load direction with the lowest fatigue life reliability between 14000–16000 cycles. Taking into account the inconsistency of the material properties, the proposed method is capable of providing the probability of failure of mass-produced parts.

  19. 49 CFR 571.204 - Standard No. 204; Steering control rearward displacement.

    Science.gov (United States)

    2010-10-01

    ... September 1, 1991. When a passenger car or a truck, bus, or multipurpose passenger vehicle with a gross... manufactured on or after September 1, 1991. When a passenger car or a truck, bus or multipurpose passenger... the steering control into the passenger compartment to reduce the likelihood of chest, neck, or head...

  20. 77 FR 14528 - Preparation for International Conference on Harmonization Steering Committee and Expert Working...

    Science.gov (United States)

    2012-03-12

    ... HUMAN SERVICES Food and Drug Administration Preparation for International Conference on Harmonization Steering Committee and Expert Working Group Meetings in Fukuoka, Japan; Regional Public Meeting AGENCY: Food and Drug Administration, HHS. ACTION: Notice of public meeting. The Food and Drug Administration...

  1. STEER: Exploring the dynamic relationship between social information and networked media through experimentation

    NARCIS (Netherlands)

    Dijkstra, S.S; Niamut, O.A; Efthymiopoulos, N.; Denazis, S.; Race, N.; Mu, M.; Taal, J.

    2015-01-01

    With the growing popularity of social networks, online video services and smart phones, the traditional content consumers are becoming the editors and broadcasters of their own stories. Within the EU FP7 project STEER, project partners have developed a novel system of new algorithms and tool sets

  2. Application of problem based learning steered by constructivism in Ophthalmologic teaching

    Directory of Open Access Journals (Sweden)

    Xin-Ling Wang

    2014-05-01

    Full Text Available AIM: To investigate the application of problem based learning(PBLsteered by constructivism. METHODS: The 120 students were appointed as the routine teaching group and the PBL steered by constructivism group separately, who were coming from the department of clinical medicine and clinical pharmacy in grade 94, China Medical University. They were divided into PBL steered by constructivism group(60 studentsand the routine teaching group(60 students. The students' feedbacks and teaching effects were compared by the questionnaire after teaching. RESULTS: The feedback of the students in the PBL steered by constructivism group were significant better than that in the routine teaching group, including interest, referring data, self-study, thought process, obtaining and spreading knowledge, computer utilization, studying independently, concerted struggling, appreciating and magnanimous ability, discussion and communication(PCONCLUSION: Application of problem based learning steered by constructivism interests the students in Ophthalmologic teaching and is helpful in their self-study, which is benefit to elevate the teaching level and train the qualified scientists.

  3. Driver Steering Support Interfaces Near the Vehicle’s Handling Limits

    NARCIS (Netherlands)

    Katzourakis, D.

    2012-01-01

    The goal of this thesis is to propose steering support systems that can reduce the driver’s control effort, mental load and promote safety. The driver dictates the vehicle’s motion and the support should centralize him/her in the control loop; thus our design philosophy is to increase driver’s

  4. Experiments in Objective Aviation Weather Forecasting Using Upper-Level Steering.

    Science.gov (United States)

    1983-12-13

    Estoque 2 and Reed 3 developed graphical 1000- mb forecast techniques, applying baroclinic theory, and these techniques steered thermal patterns using upper...none. 42 References 1. Fjbrtoft. R. (1952) On a numerical method of integrating the barotropic vorti- city equation. Tellus 4:179-194. 2. Estoque . M.A

  5. Super-resolution post-processing for satellites with yaw-steering capability

    CSIR Research Space (South Africa)

    Van den Dool, R

    2012-10-01

    Full Text Available We describe a method for improving Earth observation satellite image resolution, for specific areas of interest where the sensor design resolution is insufficient. Our method may be used for satellites with yaw-steering capability, such as Nigeria...

  6. Wheeled Vehicle Steering Systems. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Army Ordnance Center and School, Aberdeen Proving Ground, MD.

    This course is one of several subcourses that make up the entire Army correspondence course on wheeled vehicle maintenance. The subcourse is designed to provide the student with information about the operation, malfunction diagnosis, maintenance, and repair of wheeled vehicle steering systems. It provides the basic theory, and also includes…

  7. Weight gain and behavior of Raramuri Criollo versus crossbred steers developed on Chihuahuan Desert rangeland

    Science.gov (United States)

    Ranchers that raise Raramuri Criollo (RC) cattle must overcome the challenge of lack of markets for weaned calves. Growing and finishing RC or RC-crossbred steers on rangeland pastures is increasingly common; however, no data exist on their weight gains or grazing behavior. We tracked the weight a...

  8. Effects of Tall Fescue Forage Mass on Steer Ingestive Behavior and Performance

    Science.gov (United States)

    Tall fescue [Lolium arundinaceum (Schreb.) Darbysh] is a well adapted perennial pasture species utilized across the north-south transition zone of the United States and in similar environments worldwide. This 3-yr trial evaluated the influence of three forage masses (FM) on steer and pasture respons...

  9. Arginine supplementation does not alter nitrogen metabolism of beef steers during a lipopolysaccharide challenge

    Science.gov (United States)

    Demand for arginine (Arg) is reported to increase during immune challenges. This study evaluated effects of lipopolysaccharide (LPS) and abomasal Arg infusion on nitrogen (N) metabolism and immune response of 20 ruminally cannulated steers (369 ± 46 kg BW) in a randomized block design. Each block co...

  10. Performance of beef steers on Smuts finger grass and Nile grass ...

    African Journals Online (AJOL)

    Literature where animal performance is quantified for. Smuts finger grass and Nile grass pastures in South Africa is limited. In some trials, animal performance on Smuts finger grass and/or Nile grass was reported (Rhind & Goodenough,. 1979, Dannhauser, 1982 Grunow, et al., 1984). The ADG achieved by .steers on Smuts ...

  11. The Influence of Feed Energy Density and a Formulated Additive on Rumen and Rectal Temperature in Hanwoo Steers

    Directory of Open Access Journals (Sweden)

    Sangbuem Cho

    2014-11-01

    Full Text Available The present study investigated the optimum blending condition of protected fat, choline and yeast culture for lowering of rumen temperature. The Box Benken experimental design, a fractional factorial arrangement, and response surface methodology were employed. The optimum blending condition was determined using the rumen simulated in vitro fermentation. An additive formulated on the optimum condition contained 50% of protected fat, 25% of yeast culture, 5% of choline, 7% of organic zinc, 6.5% of cinnamon, and 6.5% of stevioside. The feed additive was supplemented at a rate of 0.1% of diet (orchard grass:concentrate, 3:7 and compared with a control which had no additive. The treatment resulted in lower volatile fatty acid (VFA concentration and biogas than the control. To investigate the effect of the optimized additive and feed energy levels on rumen and rectal temperatures, four rumen cannulated Hanwoo (Korean native beef breed steers were in a 4×4 Latin square design. Energy levels were varied to low and high by altering the ratio of forage to concentrate in diet: low energy (6:4 and high energy (4:6. The additive was added at a rate of 0.1% of the diet. The following parameters were measured; feed intake, rumen and rectal temperatures, ruminal pH and VFA concentration. This study was conducted in an environmentally controlled house with temperature set at 30°C and relative humidity levels of 70%. Steers were housed individually in raised crates to facilitate collection of urine and feces. The adaptation period was for 14 days, 2 days for sampling and 7 days for resting the animals. The additive significantly reduced both rumen (p<0.01 and rectal temperatures (p<0.001 without depressed feed intake. There were interactions (p<0.01 between energy level and additive on ruminal temperature. Neither additive nor energy level had an effect on total VFA concentration. The additive however, significantly increased (p<0.01 propionate and subsequently

  12. Effect of shade on body temperature and performance of feedlot steers.

    Science.gov (United States)

    Gaughan, J B; Bonner, S; Loxton, I; Mader, T L; Lisle, A; Lawrence, R

    2010-12-01

    A 120-d feedlot study using 164 Angus steers (BW = 396.7 ± 7.0 kg) was undertaken in Queensland Australia (24°84' S, 149°78' N) to determine the effect of shade on body temperature (T(B)) and performance. Cattle were allocated to 20 pens: 16 with an area of 144 m(2) (8 steers/pen) and 4 with an area of 168 m(2) (9 steers/pen). Treatments (10 pens/treatment) were unshaded (NS) vs. shaded (SH). Shade (3.3 m(2)/steer) was provided by 80% solar block shade cloth. Before the study (d -31), 63 steers were implanted (between the internal abdominal muscle and the peritoneum at the right side flank) with a T(B) transmitter. Within each pen, 3 steers had a T(B) transmitter. Individual T(B) was obtained every 30 min. The cattle were fed a feedlot diet and had ad libitum access to water. Water usage and DMI were recorded daily on a pen basis. Average daily gain and G:F were calculated on a pen basis. Climatic variables were obtained from an on-site weather station every 30 min. Individual panting scores (PS) were obtained daily at 0600, 1200, and 1600 h. From these, mean PS (MPS) were calculated for each pen. At slaughter (d 121), individual HCW, loin muscle area (LMA), rump fat depth (P8), 12th-rib fat depth, and marbling score were obtained. Mean T(B) was not affected (P > 0.05) by treatment (SH = 39.58°C; NS = 39.60°C). However, during a 21-d heat wave when cattle were exposed to a mean ambient temperature (T(AM)) > 30°C for 8 h each d (T(AM) between 0800 and 1800 h = 29.7°C, and 23.4°C between 1830 and 0730 h), the T(B) of SH steers (40.41 ± 0.10°C) was less (P 0.05) were found for LMA, P8, or marbling score. Access to shade improved (P < 0.05) ADG and G:F, increased HCW, and decreased MPS; however, shade did not completely eliminate the impact of high heat load.

  13. Den gode facilitator af refleksionsarbejde

    DEFF Research Database (Denmark)

    Jørgensen, Pia

    2009-01-01

    præsenteres i det følgende afsnit, og forfatteren argumenterer for begrebet facilitator af refleksionsarbejde. Herefter udfoldes rollen som facilitator ifølge Ghay og Lillyman. De har fokus på positive praksisoplevelser og tillidsfulde relationer. Gillie Boltons teoretiske og praktiske referenceramme...

  14. Facilitating Dialogues about Racial Realities

    Science.gov (United States)

    Quaye, Stephen John

    2014-01-01

    Background/Context: Facilitating dialogues about racial issues in higher education classroom settings continues to be a vexing problem facing postsecondary educators. In order for students to discuss race with their peers, they need skilled facilitators who are knowledgeable about racial issues and able to support students in these difficult…

  15. Determination of Steering Wheel Angles during CAR Alignment by Image Analysis Methods

    Science.gov (United States)

    Mueller, M.; Voegtle, T.

    2016-06-01

    Optical systems for automatic visual inspections are of increasing importance in the field of automation in the industrial domain. A new application is the determination of steering wheel angles during wheel track setting of the final inspection of car manufacturing. The camera has to be positioned outside the car to avoid interruptions of the processes and therefore, oblique images of the steering wheel must be acquired. Three different approaches of computer vision are considered in this paper, i.e. a 2D shape-based matching (by means of a plane to plane rectification of the oblique images and detection of a shape model with a particular rotation), a 3D shape-based matching approach (by means of a series of different perspectives of the spatial shape of the steering wheel derived from a CAD design model) and a point-to-point matching (by means of the extraction of significant elements (e.g. multifunctional buttons) of a steering wheel and a pairwise connection of these points to straight lines). The HALCON system (HALCON, 2016) was used for all software developments and necessary adaptions. As reference a mechanical balance with an accuracy of 0.1° was used. The quality assessment was based on two different approaches, a laboratory test and a test during production process. In the laboratory a standard deviation of ±0.035° (2D shape-based matching), ±0.12° (3D approach) and ±0.029° (point-to-point matching) could be obtained. The field test of 291 measurements (27 cars with varying poses and angles of the steering wheel) results in a detection rate of 100% and ±0.48° (2D matching) and ±0.24° (point-to-point matching). Both methods also fulfil the request of real time processing (three measurements per second).

  16. DETERMINATION OF STEERING WHEEL ANGLES DURING CAR ALIGNMENT BY IMAGE ANALYSIS METHODS

    Directory of Open Access Journals (Sweden)

    M. Mueller

    2016-06-01

    Full Text Available Optical systems for automatic visual inspections are of increasing importance in the field of automation in the industrial domain. A new application is the determination of steering wheel angles during wheel track setting of the final inspection of car manufacturing. The camera has to be positioned outside the car to avoid interruptions of the processes and therefore, oblique images of the steering wheel must be acquired. Three different approaches of computer vision are considered in this paper, i.e. a 2D shape-based matching (by means of a plane to plane rectification of the oblique images and detection of a shape model with a particular rotation, a 3D shape-based matching approach (by means of a series of different perspectives of the spatial shape of the steering wheel derived from a CAD design model and a point-to-point matching (by means of the extraction of significant elements (e.g. multifunctional buttons of a steering wheel and a pairwise connection of these points to straight lines. The HALCON system (HALCON, 2016 was used for all software developments and necessary adaptions. As reference a mechanical balance with an accuracy of 0.1° was used. The quality assessment was based on two different approaches, a laboratory test and a test during production process. In the laboratory a standard deviation of ±0.035° (2D shape-based matching, ±0.12° (3D approach and ±0.029° (point-to-point matching could be obtained. The field test of 291 measurements (27 cars with varying poses and angles of the steering wheel results in a detection rate of 100% and ±0.48° (2D matching and ±0.24° (point-to-point matching. Both methods also fulfil the request of real time processing (three measurements per second.

  17. Carcass characteristics and meat quality of Hereford sired steers born to beef-cross-dairy and Angus breeding cows.

    Science.gov (United States)

    Coleman, Lucy W; Hickson, Rebecca E; Schreurs, Nicola M; Martin, Natalia P; Kenyon, Paul R; Lopez-Villalobos, Nicolas; Morris, Stephen T

    2016-11-01

    Steers from Angus, Angus×Holstein Friesian, Angus×Holstein Friesian-Jersey and Angus×Jersey cows and a Hereford sire were measured for their carcass and meat quality characteristics. Steers from the Angus×Holstein Friesian cows had a greater final body weight and carcass weight (P<0.05). Steers from Angus×Jersey cows had the lowest carcass weight and dressing-out percentage (P<0.05). There was a greater fat depth over the rump at 12 and 18months of age for the steers from Angus cows (P<0.05) but, not at 24months of age. The steers had similar meat quality characteristics across the breed groups. Steers from Angus×Holstein Friesian and Angus×Jersey cows had a higher ratio of n6 to n3 fatty acids. Using beef-cross-dairy cows to produce steers for meat production does not impact on meat quality. Using Jersey in the breed cross reduced the carcass tissues in the live weight and the potential meat yield. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil.

    Science.gov (United States)

    Choi, Seong Ho; Park, Sung Kwon; Choi, Chang Weon; Li, Xiang Zi; Kim, Kyoung Hoon; Kim, Won Young; Jeong, Joon; Johnson, Bradley J; Zan, Linsen; Smith, Stephen B

    2016-03-01

    We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα) and peroxisome proliferator-activated receptor gamma (PPARγ) increased between the initial and intermediate biopsies and declined thereafter (poil decreased (p = 0.01) PPARγ gene expression at the intermediate sample time. At the terminal sample time, PPARγ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (ppalm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta (CEBPβ) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (poil decreased SCD gene expression in s.c. adipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers. Contrary to our original hypothesis, palm oil did not promote adipogenic gene expression in s.c. and i.m. adipose tissue.

  19. Crusade Microcatheter-Facilitated Reverse Wire Technique for Revascularization of Bifurcation Lesions of Coronary Arteries.

    Science.gov (United States)

    Lee, Hsin-Fu; Chou, Shing-Hsien; Tung, Ying-Chang; Lin, Chia-Pin; Ko, Yu-Shien; Chang, Chi-Jen

    2018-01-01

    This study aims to analyze the lesion characteristics of bifurcations that required reverse wire technique and the efficacy and safety of this technique in approaching branches with a highly angulated take-off. We enrolled patients in whom reverse wire technique was used after failed conventional antegrade wiring with the support of a Crusade catheter. The study endpoints were the technical success defined as succeeding in sending the reversely bent wire to the targeted branches without complications and the procedural success defined as succeeding in revascularization of the bifurcation lesions without complications. Among 158 patients with bifurcation lesions undergoing percutaneous coronary intervention using a Crusade catheter to facilitate wiring, 23 (14.6%) requiring the reverse wire technique in an attempt to access branches of the bifurcation lesions with an acutely angulated take-off were enrolled for analysis. The obtainable angle of take-off was 162.9 ± 4.7 degrees. For the parent vessel, the ostium of the targeted branch, and nontargeted branch, the minimal luminal diameters were 0.3 ± 0.5 mm, 0.4 ± 0.2 mm, and 1.8 ± 0.5 mm, respectively; the diameter stenosis were 88.8 ± 18.5%, 83.0 ± 7.3%, and 32.0 ± 14.5%, respectively. Technical and procedural success was achieved in 22 cases (96% for both). We showed in the present study that the reverse wire technique is effective and safe for approaching highly angulated branches of bifurcation lesions and consequently for complete revascularization of difficult bifurcation lesions.

  20. Behavioral characteristics of Hanwoo ( steers at different growth stages and seasons

    Directory of Open Access Journals (Sweden)

    Na Yeon Kim

    2017-10-01

    Full Text Available Objective This research analyzed behavioral characteristics of Hanwoo (Bos taurus coreanae steers during each season and growth stage to enable measurement of the animals’ welfare level for precision livestock farming. Methods A hundred-eight beef steers were divided into three equal groups at a Hanwoo farm according to their growth stage: growing stage (GS, 8 months; early-fattening stage (EFS, 19 months; and late-fattening stage (LFS, 30 months. Twelve behavioral categories were continuously recorded for 13 day-time hours in each four seasons with three replications. Results Time spent standing was found to be significantly longer in summer at all growth stages (p<0.05. Hanwoos at the GS spent significantly longer standing time in spring and summer than those at the EFS and LFS (p<0.05. Lying time in summer was the shortest for all growth stages (p<0.05. Steers at the LFS spent significantly longer lying time than that at the GS (p<0.05 in summer. For GS and EFS, time spent eating in spring and autumn were longer than in summer and winter (p<0.05. Eating time was the longest for the GS in spring, autumn, and winter, excluding for the LFS in winter (p<0.05. Regarding ruminating, steers at the LFS spent significantly shorter time than those at other stages in all seasons (p<0.05. GS and EFS steers showed the longest walking time in summer compared with other seasons (p<0.05. At GS and LFS, drinking time in summer was the longest of all seasons (p<0.05. Sleeping time was significantly shorter in summer compared with the other seasons (p<0.05. Self-grooming time was the longest in winter for all growth stages (p<0.05. Conclusion Steers were found to have more variable behavioral patterns during summer and the GS and less active behaviors during the LFS, thus extra care seems necessary during the GS, LFS, and summer period.

  1. Learning to Facilitate (Online) Meetings

    DEFF Research Database (Denmark)

    Reimann, Peter; Bull, Susan; Vatrapu, Ravi

    2013-01-01

    We describe an approach to teaching collaboration skills directly by building on competences for meeting facilitation. (Online) meetings provide a rich arena to practice collaboration since they can serve multiple purposes: learning, problem solving, decision making, idea generation and advancement...

  2. Patient advocacy: barriers and facilitators

    OpenAIRE

    Nikravesh Mansoure; Ahmadi Fazlollah; Oskouie Fatemeh; Negarandeh Reza; Hallberg Ingalill

    2006-01-01

    Abstract Background During the two recent decades, advocacy has been a topic of much debate in the nursing profession. Although advocacy has embraced a crucial role for nurses, its extent is often limited in practice. While a variety of studies have been generated all over the world, barriers and facilitators in the patient advocacy have not been completely identified. This article presents the findings of a study exploring the barriers and facilitators influencing the role of advocacy among ...

  3. On novice facilitators doing research

    DEFF Research Database (Denmark)

    Tavella, Elena

    2018-01-01

    Opportunities for novices to facilitate Problem Structuring Methods (PSMs) workshops are limited, especially because of a lack of access to real-world interventions and confidence in their capabilities. Novices are usually young academics building their careers through publishing. Publishing...... is challenging if facilitation and opportunities for data collection are limited. To address this challenge, this paper suggests autoethnography as a framework for addressing difficulties that novices face in conducting research and publishing on PSMs. This suggestion grows out of a literature study...

  4. Comparative effects of zilpaterol hydrochloride and ractopamine hydrochloride on live performance and carcass characteristics of calf-fed Holstein steers.

    Science.gov (United States)

    Brown, T R; Sexten, A K; Lawrence, T E; Miller, M F; Thomas, C L; Yates, D A; Hutcheson, J P; Hodgen, J M; Brooks, J C

    2014-09-01

    Holstein steers (n = 2,275) were assigned to 1 of 3 treatments: 1) a control diet containing no β-agonists, 2) a diet that contained zilpaterol hydrochloride (ZH; 8.3 mg/kg [100% DM basis]) for 20 d with a 3-d withdrawal period before harvest, and 3) a diet that contained ractopamine hydrochloride (RH; 30.1 mg/kg [100% DM basis]) for 28 d before harvest. No differences (P ≥ 0.18) were detected between treatments for initial BW, BW at d 28, or DMI. Final BW, BW gain for the last 28 d, total BW gain, ADG for the last 28 d, and overall ADG were greater (P < 0.05) for steers fed ZH or RH than for steers fed the control diet. Additionally, G:F for the last 28 d and G:F for the entire trial was increased (P < 0.02) for steers fed ZH (0.147, 0.147) or RH (0.153, 0.151) compared to steers fed the control diet (0.134, 0.143), respectively. Steers fed ZH or RH had HCW that were 15.5 and 8.2 kg heavier (P ≤ 0.01) and LM areas that were 7.1 and 2.3 cm(2) larger (P < 0.01) than control cattle. Steers fed ZH also had dressed carcass yields that were 1.3% to 1.5% greater and USDA calculated yield grades that were decreased 0.16 to 0.23 units compared to RH and control steers. No differences (P ≥ 0.39) were found between treatments for marbling score, fat thickness, and percentage KPH. Steers fed ZH had an increased (P ≤ 0.04) percentage of yield grade 1 and 2 carcasses (15.1, 55.0) and a reduced (P ≤ 0.02) percentage of yield grade 3 carcasses (27.1) compared with those fed RH (10.5, 49.1, 36.1) or the control diet (9.0, 47.4, 36.4), respectively. Additionally, ZH-fed steers had a decreased (P ≤ 0.04) percentage of yield grade 4 and 5 carcasses (2.8) compared with steers fed the control diet (6.9). Steers fed ZH had an increased (P ≤ 0.01) percentage of USDA Select grading carcass (31.0%) and a decreased (P ≤ 0.01) percentage of USDA Choice grading carcasses (65.0%) compared with steers fed RH (25.8%, 70.2%) and no β-agonist (24.8%, 72.0%), respectively. Feeding

  5. MATHEMATICAL MODELING OF WORKING PROCESS IN HYDRAULIC DRIVE OF SPECIFICALLY HEAVY-DUTY TRUCK STEERING

    Directory of Open Access Journals (Sweden)

    E. M. Zabolotsky

    2006-01-01

    Full Text Available The paper provides an analysis that shows application of pump-controlled steering hydraulic drives. Dynamic model of steering hydraulic drive of open-cast BelAZ-75131 dump truck developed at BNTU and also mathematical models for circuit consisting of a metering pump and a turning cylinder and a flow amplifier and a turning cylinder with due account of compressibility and resistance of service drain line. It is noted that on the basis of the given methodology a multi-variant dynamic calculation has been carried out, drive dynamics has been analyzed at various design and component parameters of a metering pump and a flow amplifier, rational values of these parameters has been selected for design development. The paper also gives an algorithm scheme for the solution of the derived equation systems.

  6. Autonomous Coil Alignment System Using Fuzzy Steering Control for Electric Vehicles with Dynamic Wireless Charging

    Directory of Open Access Journals (Sweden)

    Karam Hwang

    2015-01-01

    Full Text Available An autonomous coil alignment system (ACAS using fuzzy steering control is proposed for vehicles with dynamic wireless charging. The misalignment between the power receiver coil and power transmitter coil is determined based on the voltage difference between two coils installed on the front-left/front-right of the power receiver coil and is corrected through autonomous steering using fuzzy control. The fuzzy control is chosen over other control methods for implementation in ACAS due to the nonlinear characteristic between voltage difference and lateral misalignment distance, as well as the imprecise and constantly varying voltage readings from sensors. The operational validity and feasibility of the ACAS are verified through simulation, where the vehicle equipped with ACAS is able to align with the power transmitter in the road majority of the time during operation, which also implies achieving better wireless power delivery.

  7. Modal analysis in relation to the casing of an electric power steering system

    Science.gov (United States)

    Baier, A.; Herbuś, K.; Ociepka, P.; Płaczek, M.

    2017-08-01

    The article presents the results of modal analysis (experimental and numerical using Finite Element Method - FEM) with reference to the power steering worm drive gear housing. The experimental analysis was performed by the Least Squares Complex Exponential (LSCE) method using a modal hammer equipped with a force sensor which allowed the measurement and recording of the excitation. Numerical analysis was based on the Finite Element Method in PLM Siemens NX 10. Based on results from the experimental modal analysis the FEM numerical model was tuned. The resulting consistency of results led to the conclusion the correctness of the model FEM. The adapted numerical model was used for further analysis with respect to modified power steering worm drive gear housing designs. The obtained results allowed to estimate how the change of the material and adjusting the geometrical form to the strength conditions will affect the frequency and form of the vibration of the modified worm drive gear housing.

  8. Analysis of a double steering forest trailer for long wood log transportation

    Directory of Open Access Journals (Sweden)

    Francesco Marinello

    2013-09-01

    Full Text Available A cost effective technical solution of a forest double steering trailer was studied and tested, allowing decrease of radius of curvature and increase of the maneuverability, independently from the length of the transported logs. The steering system improves the so called “stingertype truck” configuration using an articulated frame; through a rearward hinge, the front wheels direction mechanically controls and adapts the direction of rear twin wheels. The study was based on CAD simulations considering the dimensions of the trailer transporting logs with a length up to 12 m. For different log lengths the simulation analyzed the total maneuver area, in terms of minimum curve radius and curve widening. A field test on a prototype operated for transport of long logs along a representative forest road in the Alps was carried out. The results confirm the improvements foreseen by CAD simulations, with allowed curve radius down to 6 m, even with 12 m logs.

  9. Utilization of an ultrasound beam steering angle for measurements of tissue displacement vector and lateral displacement

    Directory of Open Access Journals (Sweden)

    Chikayoshi Sumi

    2010-09-01

    Full Text Available Chikayoshi SumiDepartment of Information and Communication Sciences, Faculty of Science and Technology, Sophia University, Tokyo, JapanAbstract: A number of ultrasonic displacement/velocity measurement methods have been extensively developed for measurements of blood flow, tissue motion, and strain. Lateral modulation (LM methods have also been reported using steered, crossed beams, and these methods permit measurements of displacement vectors. In this report, a new beam steering method for the transmission and reception of ultrasound is proposed, which can enable measurements of lateral displacements and of arbitrary displacement vectors with a very high degree of accuracy. Because this beam steering method uses only a steering angle, this method is referred to as ASTA. With ASTA, the number of available methods to obtain a displacement vector measurement is limited to previously developed block-matching methods, such as the multidimensional cross-spectrum phase gradient method, and the multidimensional autocorrelation method (MAM and the multidimensional Doppler method (MDM using a block-matching method (the methods using block matching are referred to as MAMb and MDMb, respectively. Being dependent on the measurement method, only a lateral displacement measurement can be made even if the methods are multidimensional, ie, previously developed MAM and MDM using a moving average and a mirror setting of the obtained steered beams, and one-dimensional (1D, such as an autocorrelation method. Considerations of beamforming schemes using LM and ASTA show that the simple ASTA beamforming method increases capabilities for real-time measurements and requires a small physical aperture when compared with LM. For lateral displacement measurements (eg, blood flow in a carotid artery, a lateral coordinate must correspond to the direction of the target’s lateral motion, and the steering angle used is as large as possible to increase the measurement accuracy

  10. Decoupling control of steering and driving system for in-wheel-motor-drive electric vehicle

    Science.gov (United States)

    Zhang, Han; Zhao, Wanzhong

    2018-02-01

    To improve the maneuverability and stability of in-wheel-motor-drive electric vehicle, a control strategy based on nonlinear decoupling control method is proposed in this paper, realizing the coordinated control of the steering and driving system. At first, the nonlinear models of the in-wheel-motor-drive electric vehicle and its sub-system are constructed. Then the inverse system decoupling theory is applied to decompose the nonlinear system into several independent subsystems, which makes it possible to realize the coordinated control of each subsystem. Next, the μ-Synthesis theory is applied to eliminate the influence of model uncertainty, improving the stability, robustness and tracking performance of in-wheel-motor-drive electric vehicle. Simulation and experiment results and numerical analyses, based on the electric vehicle actuated by in-wheel-motors, prove that the proposed control method is effective to accomplish the decoupling control of the steering and driving system in both simulation and real practice.

  11. Research on Precision Tracking on Fast Steering Mirror and Control Strategy

    Science.gov (United States)

    Di, Lin; Yi-ming, Wu; Fan, Zhu

    2018-01-01

    Fast steering mirror is a device used for controlling the beam direction precisely. Due to the short travel of the push-pull FSM, a compound fast steering mirror system driven by both limited-angle voice coil motor and push-pull FSM together is proposed. In the compound FSM system, limited-angle voice coil motor quickly swings at wide angle, while the push-pull FSM do high frequency movement in a small range, which provides the system with the high bandwidth and long travel. In the control strategy, the method of combining feed-forward control in Kalman filtering with auto-disturbance rejection control is used to improve trajectory tracking accuracy. The simulation result shows that tracking accuracy measured by the compound method can be improved by more than 5 times than that of the conventional PID.

  12. Improvement of the directional stability of passenger car trailer couplings with actively controlled steering

    Science.gov (United States)

    Desens, Jens

    The stabilization of pendulum oscillations of passenger car trailer couplings, using active steering, was examined. A linear model of the couplings was presented. Each axle was provided with a controller. The controllers were optimized, with regard to necessary sensors, in order to minimize costs. The rear and the front axles were provided with a control unit in order to compute the potential prevailing in the active steering of several axles. It was shown that the passenger car rear axle was the most suitable for coupling stabilization. The experiment was simulated, using a complex coupling model. The developed controller allowed the passenger car trailer to be driven at a speed higher than 150 km per hour.

  13. Identification of fast-steering mirror based on chicken swarm optimization algorithm

    Science.gov (United States)

    Ren, Wei; Deng, Chao; Zhang, Chao; Mao, Yao

    2017-06-01

    According to the transfer function identification method of fast steering mirror exists problems which estimate the initial value is complicated in the process of using, put forward using chicken swarm algorithm to simplify the identification operation, reducing the workload of identification. chicken swarm algorithm is a meta heuristic intelligent population algorithm, which shows global convergence is efficient in the identification experiment, and the convergence speed is fast. The convergence precision is also high. Especially there are many parameters are needed to identificate in the transfer function without considering the parameters estimation problem. Therefore, compared with the traditional identification methods, the proposed approach is more convenient, and greatly achieves the intelligent design of fast steering mirror control system in enginerring application, shorten time of controller designed.

  14. Autonomous trajectory generation for mobile robots with non-holonomic and steering angle constraints

    International Nuclear Information System (INIS)

    Pin, F.G.; Vasseur, H.A.

    1990-01-01

    This paper presents an approach to the trajectory planning of mobile platforms characterized by non-holonomic constraints and constraints on the steering angle and steering angle rate. The approach is based on geometric reasoning and provides deterministic trajectories for all pairs of initial and final configurations (position x, y, and orientation θ) of the robot. Furthermore, the method generates trajectories taking into account the forward and reverse mode of motion of the vehicle, or combination of these when complex maneuvering is involved or when the environment is obstructed with obstacles. The trajectory planning algorithm is described, and examples of trajectories generated for a variety of environmental conditions are presented. The generation of the trajectories only takes a few milliseconds of run time on a micro Vax, making the approach quite attractive for use as a real-time motion planner for teleoperated or sensor-based autonomous vehicles in complex environments. 10 refs., 11 figs

  15. The Relationship Between Extratropical Cyclone Steering and Blocking Along the North American East Coast

    Science.gov (United States)

    Booth, James F.; Dunn-Sigouin, Etienne; Pfahl, Stephan

    2017-12-01

    The path and speed of extratropical cyclones along the east coast of North America influence their societal impact. This work characterizes the climatological relationship between cyclone track path and speed, and blocking and the North Atlantic Oscillation (NAO). An analysis of Lagrangian cyclone track propagation speed and angle shows that the percentage of cyclones with blocks is larger for cyclones that propagate northward or southeastward, as is the size of the blocked region near the cyclone. Cyclone-centered composites show that propagation of cyclones relative to blocks is consistent with steering by the block: northward tracks more often have a block east/northeast of the cyclone; slow tracks tend to have blocks due north of the cyclone. Comparison with the NAO shows that to first-order blocking and the NAO steer cyclones in a similar manner. However, blocked cyclones are more likely to propagate northward, increasing the likelihood of cyclone related impacts.

  16. Autonomous collision avoidance system by combined control of steering and braking using geometrically optimised vehicular trajectory

    Science.gov (United States)

    Hayashi, Ryuzo; Isogai, Juzo; Raksincharoensak, Pongsathorn; Nagai, Masao

    2012-01-01

    This study proposes an autonomous obstacle avoidance system not only by braking but also by steering, as one of the active safety technologies to prevent traffic accidents. The proposed system prevents the vehicle from colliding with a moving obstacle like a pedestrian jumping out from the roadside. In the proposed system, to avoid the predicted colliding position based on constant-velocity obstacle motion assumption, the avoidance trajectory is derived as connected two identical arcs. The system then controls the vehicle autonomously by the combined control of the braking and steering systems. In this paper, the proposed system is examined by real car experiments and its effectiveness is shown from the results of the experiments.

  17. Frequency Invariant Beam Steering for Short-Pulse Systems with a Rotman Lens

    Directory of Open Access Journals (Sweden)

    Andreas Lambrecht

    2010-01-01

    Full Text Available A promising approach for beam steering of high-voltage transient signals for HPEM-systems (High Power Electro Magnetic is presented. The inherent capability of the Rotman lens to provide true time delays is used to develop a prototype beam steering device for an antielectronics HPEM system in the frequency range from 350 MHz to 5 GHz. Results of analytical calculations, simulations, and measurements from a hardware prototype are presented. The detailed mechanical setup of the Rotman lens is presented. Additionally the output pulses are investigated when inputting a Gaussian-like transient signal. Then time domain measures of quality (full width at half maximum, ringing, delay spread, maximum of transfer function are investigated for these output transients, and the simulation and measurement results are compared. A concluding analysis of the realizable time domain array pattern shows the radiated pulse form.

  18. ADDJUST - An automated system for steering Centaur launch vehicles in measured winds

    Science.gov (United States)

    Swanson, D. C.

    1977-01-01

    ADDJUST (Automatic Determination and Dissemination of Just-Updated Steering Terms) is an automated computer and communication system designed to provide Atlas/Centaur and Titan/Centaur launch vehicles with booster-phase steering data on launch day. Wind soundings are first obtained, from which a smoothed wind velocity vs altitude relationship is established. Design for conditions at the end of the boost phase with initial pitch and yaw maneuvers, followed by zero total angle of attack through the filtered wind establishes the required vehicle attitude as a function of altitude. Polynomial coefficients for pitch and yaw attitude vs altitude are determined and are transmitted for validation and loading into the Centaur airborne computer. The system has enabled 14 consecutive launches without a flight wind delay.

  19. Multipartite Einstein-Podolsky-Rosen steering and genuine tripartite entanglement with optical networks

    Science.gov (United States)

    Armstrong, Seiji; Wang, Meng; Teh, Run Yan; Gong, Qihuang; He, Qiongyi; Janousek, Jiri; Bachor, Hans-Albert; Reid, Margaret D.; Lam, Ping Koy

    2015-02-01

    Einstein, Podolsky and Rosen (EPR) pointed out in their famous paradox that two quantum-entangled particles can have perfectly correlated positions and momenta. Such correlations give evidence for the nonlocality of quantum mechanics and form the basis for quantum cryptography and teleportation. EPR steering is the nonlocality associated with the EPR paradox and has traditionally been investigated between only two parties. Using optical networks and efficient detection, we present experimental observations of multiparty EPR steering and of the genuine entanglement of three intense optical beams. We entangle the quadrature phase amplitudes of distinct fields, in analogy to the position-momentum entanglement of the original paradox. Our experiments complement tests of quantum mechanics that have entangled small systems or have demonstrated tripartite inseparability. Our methods establish principles for the development of multiparty quantum communication protocols with asymmetric observers, and can be extended to qubits, whether photonic, atomic, superconducting, or otherwise.

  20. Helicopter downwash measured by continuous-wave Doppler lidars with agile beam steering

    DEFF Research Database (Denmark)

    Sjöholm, Mikael; Angelou, Nikolas; Hansen, Per

    2012-01-01

    A ground-based remote sensing short-range WindScanner with agile beam steering based on a modified ZephIR continuous-wave wind lidar (LIght Detection And Ranging) and a double prism arrangement has recently been developed at the Department of Wind Energy at the DTU Risø campus. The WindScanner me......A ground-based remote sensing short-range WindScanner with agile beam steering based on a modified ZephIR continuous-wave wind lidar (LIght Detection And Ranging) and a double prism arrangement has recently been developed at the Department of Wind Energy at the DTU Risø campus. The Wind...

  1. How to Steer and Lead Educational Processes in a Digital Medium Environment?

    DEFF Research Database (Denmark)

    Tække, Jesper

    This paper is about challenges to steering and leadership of educational interaction in classrooms provided by the new medium environment that comes with digital media. In the new medium environment, the old way of steering what is going on in the classroom appears not to work any more since...... by systems theory the paper sketches an outline of a more adequate way of teaching in the new medium environment – a teaching that can manage the new situation and use the new possibilities provided by the digital media. The paper builds on empirical findings from the action research project Socio Media...... Education (SME), which has worked with possibilities and problems in regard to the digital medium revolution’s disruption of the Danish upper secondary school (Tække & Paulsen 2015a, b, 2014, 2013a, b, c, 2012)....

  2. Ionophore strategy affects growth performance and carcass characteristics in feedlot steers.

    Science.gov (United States)

    Thompson, A J; Smith, Z K F; Corbin, M J; Harper, L B; Johnson, B J

    2016-12-01

    One hundred ninety-two steers (BW = 354 ± 23.5 kg) were used in a randomized block design to evaluate the effects of ionophore and ractopamine hydrochloride (RH) supplementation strategies on performance and carcass characteristics. Twelve pens of 4 steers were assigned to each of the following treatments: unsupplemented control (CON), laidlomycin propionate (12.1 mg/kg DM) with or without RH (LPRH and LP, respectively), and monensin sodium (36.4 mg/kg DM) with RH (MSRH). Steers were fed for 151 d, of which respective treatments received RH (Actogain; Zoetis, Florham Park, NJ) at a rate of 300 mg/(animal · d) for the final 32 d. Laidlomycin was removed from the LPRH treatment during this period, as no combination feeding has been approved. Upon harvest, carcass data were collected by trained personnel, and subsequent analysis of the LM was conducted to estimate tenderness using Warner-Bratzler shear force (WBSF). Prior to RH supplementation, both LP and LPRH had greater ADG ( ≤ 0.02) and G:F ( Ractopamine increased LM area in MSRH-supplemented cattle ( = 0.03) and tended to increase LM area for steers receiving LPRH ( = 0.07). Longissimus steaks of MSRH-supplemented cattle had greater WBSF values than CON ( = 0.04) after 7 d of postmortem aging and greater WBSF values than LPRH steaks after 28 d ( = 0.03). All other carcass and WBSF measurements were similar among treatments. The results of this study indicate that LP supplementation without RH may yield a performance similar to and carcass responses associated with the administration of a β-agonist. These results also suggest that performance and carcass characteristics for cattle fed LP are similar to those of cattle fed monensin throughout the feeding period.

  3. Minutes of Technical Division Steering Committee Meeting, September 13, 1955 -- Savannah River Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.C.

    1955-09-16

    The Steering Committee approved 8 studies related to separation processes, analytical chemistry, waste handling, and recycle development. Safety and security issues were discussed. Appendices detail the financial status of the Technical Division and estimated man months for development studies approved for the Purex Process, tritium separations, thorium recycle, U-235 separations, and 100-, 200-, and 300-Area studies in analytical chemistry development. The status of 25 other Technical Division studies are listed along with their budget.

  4. A novel, flat, electronically-steered phased array transducer for tissue ablation: preliminary results

    International Nuclear Information System (INIS)

    Ellens, Nicholas P K; Lucht, Benjamin B C; Gunaseelan, Samuel T; Hudson, John M; Hynynen, Kullervo H

    2015-01-01

    Flat, λ/2-spaced phased arrays for therapeutic ultrasound were examined in silico and in vitro. All arrays were made by combining modules made of 64 square elements with 1.5 mm inter-element spacing along both major axes. The arrays were designed to accommodate integrated, co-aligned diagnostic transducers for targeting and monitoring. Six arrays of 1024 elements (16 modules) and four arrays of 6144 elements (96 modules) were modelled and compared according to metrics such as peak pressure amplitude, focal size, ability to be electronically-steered far off-axis and grating lobe amplitude. Two 1024 element prototypes were built and measured in vitro, producing over 100 W of acoustic power. In both cases, the simulation model of the pressure amplitude field was in good agreement with values measured by hydrophone. Using one of the arrays, it was shown that the peak pressure amplitude dropped by only 24% and 25% of the on-axis peak pressure amplitude when steered to the edge of the array (40 mm) at depths of 30 mm and 50 mm. For the 6144 element arrays studied in in silico only, similarly high steerability was found: even when steered 100 mm off-axis, the pressure amplitude decrease at the focus was less than 20%, while the maximum pressure grating lobe was only 20%. Thermal simulations indicate that the modules produce more than enough acoustic power to perform rapid ablations at physiologically relevant depths and steering angles. Arrays such as proposed and tested in this study have enormous potential: their high electronic steerability suggests that they will be able to perform ablations of large volumes without the need for any mechanical translation. (paper)

  5. Drug design based on x-ray diffraction and steered molecular dynamics

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich; Skálová, Tereza; Dohnálek, Jan; Dušková, Jarmila; Petroková, Hana; Vondráčková, Eva; Zimmermann, K.

    2005-01-01

    Roč. 12, č. 3 (2005), s. 208-210 ISSN 1211-5894. [VUFB Conference on Modern Methods in Synthesis and Analysis of Active Pharmaceutical Substances /5./. Praha, 23.11.2005-24.11.2005] R&D Projects: GA AV ČR KJB4050312 Institutional research plan: CEZ:AV0Z40500505 Keywords : drug design * X-ray diffraction * steered molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry

  6. Annual report for the steering committee of the association Euratom-Belgian State for fusion 1996

    Energy Technology Data Exchange (ETDEWEB)

    Moons, F.; Bogaerts, W.; Decreton, M.; Biver, E.; Coenen, S.; Benoit, Ph.; Coheur, L.; Deboodt, P.; Andreev, D.

    1996-09-01

    This report is prepared for the annual steering committee meting of the Association Euratom - Belgian State for Fusion. The period October 1995 to September 1996 is reported on.The fusion technology work performed at the Belgian Nuclear Research Centre SCK/CEN, the Department of Metallurgy and Materials Engineering of the Louvain University (Belgium) and S.A. Gradel, a Luxemburg company, is described.

  7. Vehicle having hydraulic and power steering systems using a single high pressure pump

    Science.gov (United States)

    Bartley, Bradley E.; Blass, James R.; Gibson, Dennis H.

    2001-06-22

    A vehicle comprises a plurality of wheels attached to a vehicle housing. Also attached to the vehicle housing is a power steering system, including a fluid flow circuit, which is operably coupled to a number of the wheels. An internal combustion engine attached to the vehicle housing is connected to a hydraulically actuated system that includes a high pressure pump. An outlet of the high pressure pump is in fluid communication with the fluid flow circuit.

  8. Where we look when we drive with or without active steering wheel control.

    Directory of Open Access Journals (Sweden)

    Franck Mars

    Full Text Available Current theories on the role of visuomotor coordination in driving agree that active sampling of the road by the driver informs the arm-motor system in charge of performing actions on the steering wheel. Still under debate, however, is the nature of visual cues and gaze strategies used by drivers. In particular, the tangent point hypothesis, which states that drivers look at a specific point on the inside edge line, has recently become the object of controversy. An alternative hypothesis proposes that drivers orient gaze toward the desired future path, which happens to be often situated in the vicinity of the tangent point. The present study contributed to this debate through the analyses of the distribution of gaze orientation with respect to the tangent point. The results revealed that drivers sampled the roadway in the close vicinity of the tangent point rather than the tangent point proper. This supports the idea that drivers look at the boundary of a safe trajectory envelop near the inside edge line. Furthermore, the study investigated for the first time the reciprocal influence of manual control on gaze control in the context of driving. This was achieved through the comparison of gaze behavior when drivers actively steered the vehicle or when steering was performed by an automatic controller. The results showed an increase in look-ahead fixations in the direction of the bend exit and a small but consistent reduction in the time spent looking in the area of the tangent point when steering was passive. This may be the consequence of a change in the balance between cognitive and sensorimotor anticipatory gaze strategies. It might also reflect bidirectional coordination control between the eye and arm-motor systems, which goes beyond the common assumption that the eyes lead the hands when driving.

  9. Endocannabinoids concentrations in plasma associated with feed efficiency and carcass composition of beef steers.

    Science.gov (United States)

    Artegoitia, V M; Foote, A P; Lewis, R M; King, D A; Shackelford, S D; Wheeler, T L; Freetly, H C

    2016-12-01

    Endocannabinoids, including anandamide (AEA) and 2-arachidonoylglycerol (2-AG), are a class of endogenous lipid mediators that activate cannabinoids receptors and may be involved in the control of feed intake and energy metabolism. The objective of this study was to quantify AEA and 2-AG in plasma and identify possible associations with production traits and carcass composition in finishing beef steers. Individual DMI and BW gain were measured on 140 Angus-sired steers for 105 d on a finishing ration. Blood samples were collected on d 84 of the experiment, which was 40 d before slaughter. Variables were analyzed using Pearson CORR procedure of SAS. Mean endocannabinoid concentrations in plasma were 4.48 ± 1.82 ng/mL and 0.44 ± 0.24 ng/mL for AEA and 2-AG, respectively. The AEA concentration was positively correlated with G:F ratio ( = 0.20; = 0.02), indicating that more efficient animals had greater AEA plasma concentrations. In addition, AEA concentration tended to be negatively correlated with the 12th rib fat thickness ( = -0.17; = 0.07); but no correlation was found with USDA-calculated yield grade ( = -0.14; = 0.11), or marbling score ( = 0.05; = 0.54). The concentration of 2-AG was positively correlated with AEA ( = 0.21; = 0.01); however, 2-AG concentration was not correlated with parameters of feed efficiency or carcass composition. To our knowledge, this study is the first to report plasma concentration of endocannabinoids in steers. These results provide evidence that plasma concentration of a key endocannabinoid, AEA, was favorably correlated with feed efficiency and fat thickness in finishing steers.

  10. Beam steering of the acoustic metasurface under a subwavelength periodic modulation

    Science.gov (United States)

    Cai, Li; Wen, Jihong; Yu, Dianlong; Lu, Zhimiao; Chen, Xing; Zhao, Xiang

    2017-11-01

    In this study, we introduce a subwavelength periodic thin plate array into an acoustic metasurface and investigate the modulation effect on acoustic surface waves. Both anomalous sound refraction and reflection are observed in the metasurface, and an analytic expression is derived to clarify the underlying mechanism. We theoretically prove that flexible beam steering can be realized by phase gradient acoustic metasurfaces with deep subwavelength periodic modulation. This study potentially adds another degree of freedom to controlling sound transmission by using an acoustic metasurface.

  11. Steering a Tractor by Means of an EMG-Based Human-Machine Interface

    Science.gov (United States)

    Gomez-Gil, Jaime; San-Jose-Gonzalez, Israel; Nicolas-Alonso, Luis Fernando; Alonso-Garcia, Sergio

    2011-01-01

    An electromiographic (EMG)-based human-machine interface (HMI) is a communication pathway between a human and a machine that operates by means of the acquisition and processing of EMG signals. This article explores the use of EMG-based HMIs in the steering of farm tractors. An EPOC, a low-cost human-computer interface (HCI) from the Emotiv Company, was employed. This device, by means of 14 saline sensors, measures and processes EMG and electroencephalographic (EEG) signals from the scalp of the driver. In our tests, the HMI took into account only the detection of four trained muscular events on the driver’s scalp: eyes looking to the right and jaw opened, eyes looking to the right and jaw closed, eyes looking to the left and jaw opened, and eyes looking to the left and jaw closed. The EMG-based HMI guidance was compared with manual guidance and with autonomous GPS guidance. A driver tested these three guidance systems along three different trajectories: a straight line, a step, and a circumference. The accuracy of the EMG-based HMI guidance was lower than the accuracy obtained by manual guidance, which was lower in turn than the accuracy obtained by the autonomous GPS guidance; the computed standard deviations of error to the desired trajectory in the straight line were 16 cm, 9 cm, and 4 cm, respectively. Since the standard deviation between the manual guidance and the EMG-based HMI guidance differed only 7 cm, and this difference is not relevant in agricultural steering, it can be concluded that it is possible to steer a tractor by an EMG-based HMI with almost the same accuracy as with manual steering. PMID:22164006

  12. Annual report for the steering committee of the association Euratom-Belgian State for fusion 1996

    International Nuclear Information System (INIS)

    Moons, F.; Bogaerts, W.; Decreton, M.; Biver, E.; Coenen, S.; Benoit, Ph.; Coheur, L.; Deboodt, P.; Andreev, D.

    1996-09-01

    This report is prepared for the annual steering committee meting of the Association Euratom - Belgian State for Fusion. The period October 1995 to September 1996 is reported on.The fusion technology work performed at the Belgian Nuclear Research Centre SCK/CEN, the Department of Metallurgy and Materials Engineering of the Louvain University (Belgium) and S.A. Gradel, a Luxemburg company, is described

  13. Rumen fermentation and performance of Hanwoo steers fed total mixed ration with Korean rice wine residue.

    Science.gov (United States)

    Jeong, Chang-Dae; Mamuad, Lovelia L; Ko, Jong Youl; Sung, Ha Guyn; Park, Keun Kyu; Lee, Yoo Kyung; Lee, Sang-Suk

    2016-01-01

    This study was conducted to evaluate the effects of adding Korean rice wine residue (RWR) in total mixed ration (TMR) on in vitro ruminal fermentation and growth performance of growing Hanwoo steers. For in vitro fermentation, the experimental treatments were Control (Con: 0 % RWR + TMR), Treatment 1 (T1: 10 % RWR + TMR), and Treatment 2 (T2: 15 % RWR + TMR). The rumen fluid was collected from three Hanwoo steers and mixed with buffer solution, after which buffered rumen fluid was transferred into serum bottles containing 2 g dry matter (DM) of TMR added with or without RWR. The samples were then incubated for 0 h, 12 h, 24 h, or 48 h at 39 °C and 100 rpm. For the in vivo experiment, 27 Hanwoo steers (6 months old) with an average weight of 196 ± 8.66 kg were subjected to a 24-week feeding trial. The animals were randomly selected and equally distributed into three groups. After which the body weight, feed intake and blood characteristics of each group were investigated. The pH of the treatments decreased significantly relative to the control during the 12 h of incubation. Total gas production and ammonia nitrogen (NH3-N) was not affected by RWR addition. The total volatile fatty acid (VFA) was lower after 24 h of incubation but at other incubation times, the concentration was not affected by treatments. Feed cost was 8 % and 15 % lower in T1 and T2 compared to control. Blood alcohol was not detected and a significant increase in total weight gain and average daily gain were observed in Hanwoo steers fed with RWR. Overall, the results of this study suggest that TMR amended with 15 % RWR can be used as an alternative feed resource for ruminants to reduce feed cost.

  14. EPR steering and its application to fundamental questions in bell nonlocality

    OpenAIRE

    Bowles, Joseph

    2016-01-01

    Quantum theory is known to lead to correlations between the outcomes of measurements performed on distant systems that are strictly stronger than those obtained by any classical theory. Such correlations, termed nonlocal, highlight the radical departure of quantum theory from classical formulations of physics. Here, we study fundamental questions about the nature of nonlocal correlations in quantum theory, using as a tool the recently developed field of EPR steering. In the second part of the...

  15. Control of A Five-axle, Three-steering Coupled-vehicle System

    Science.gov (United States)

    Yamaguchi, Hiroaki; Mori, Masato; Kawakami, Atsushi

    This paper presents a new type of coupled-vehicle system: a five-axle, three-steering coupled-vehicle system and its path following feedback control law. The coupled-vehicle system consists of two car-like mobile robots, two carriers and a steering system. One of the two car-like mobile robots is coupled by one of the two carriers via a revolute joint passively rotating and the other car-like mobile robot is also coupled by one remaining carrier via a passive revolute joint, and the two carriers are coupled via another passive revolute joint. The steering system is attached to one of the carriers and its steering axis is located at the same position of the rotating axis of the passive revolute joint coupling the two carriers. We first show that, by assuming virtual mechanical elements, it is possible to convert the kinematical equation of the coupled-vehicle system into three-chain, single-generator chained form in a coordinate system in which a path two times differentiable is an axis and a straight line perpendicular to the tangent of the path is another axis. Based on chained form, we secondly derive the path following feedback control law which enables the orientations of the two carriers relative to the tangent of the path to be controllable. By the feedback control law, it is possible to cause the two carriers to form a line-shaped composed carrier or a V-shaped composed carrier and to cause them to keep such shapes while performing a path following behavior, which means that the coupled-vehicle system is able to adapt the shape of the composed carrier to the shape of a transported object. The validity of the mechanical design of the coupled-vehicle system and its path following feedback control law has been verified experimentally.

  16. Steering a Tractor by Means of an EMG-Based Human-Machine Interface

    Directory of Open Access Journals (Sweden)

    Sergio Alonso-Garcia

    2011-07-01

    Full Text Available An electromiographic (EMG-based human-machine interface (HMI is a communication pathway between a human and a machine that operates by means of the acquisition and processing of EMG signals. This article explores the use of EMG-based HMIs in the steering of farm tractors. An EPOC, a low-cost human-computer interface (HCI from the Emotiv Company, was employed. This device, by means of 14 saline sensors, measures and processes EMG and electroencephalographic (EEG signals from the scalp of the driver. In our tests, the HMI took into account only the detection of four trained muscular events on the driver’s scalp: eyes looking to the right and jaw opened, eyes looking to the right and jaw closed, eyes looking to the left and jaw opened, and eyes looking to the left and jaw closed. The EMG-based HMI guidance was compared with manual guidance and with autonomous GPS guidance. A driver tested these three guidance systems along three different trajectories: a straight line, a step, and a circumference. The accuracy of the EMG-based HMI guidance was lower than the accuracy obtained by manual guidance, which was lower in turn than the accuracy obtained by the autonomous GPS guidance; the computed standard deviations of error to the desired trajectory in the straight line were 16 cm, 9 cm, and 4 cm, respectively. Since the standard deviation between the manual guidance and the EMG-based HMI guidance differed only 7 cm, and this difference is not relevant in agricultural steering, it can be concluded that it is possible to steer a tractor by an EMG-based HMI with almost the same accuracy as with manual steering.

  17. Beam steering and coordinate system rotation improves accuracy of ultrasonic measurements of tissue displacement vector and lateral displacement

    Directory of Open Access Journals (Sweden)

    Sumi C

    2011-11-01

    Full Text Available Chikayoshi Sumi1,2, Kento Ichimaru2, Yusuke Shinozuka21Department of Information and Communication Science, 2Department of Electrical and Electronics Engineering, Faculty of Science and Technology, Sophia University, Kioi-cho, Chiyoda-ku, Tokyo, JapanAbstract: With the proper use of beam steering and apodization, a higher resolution lateral echo image is obtained than with conventional imaging. This is achieved by superimposing crossed, steered beams, which is referred to as “lateral modulation” (LM. This type of beamforming achieves almost the same accuracy in lateral displacement measurements as in axial displacement measurements, ie, displacement vector measurements. The steering angle (ASTA can also be used instead of LM, which uses only beams with a steering angle. In this report, the accuracy of the displacement vectors and lateral displacement measurements for LM and ASTA were evaluated using simulations and agar phantom experiments. The parameters used were direction of a displacement vector, steering angles, and rotation angle for the coordinate system. Changes in the steering angle and rotation angle of the coordinate system permit control of frequencies in the respective directions of the coordinate axes. As shown, when performing a simple ASTA for displacement vector measurement, a spectra frequency division should be performed using a previously developed multidimensional autocorrelation or Doppler method instead of block-matching methods. In this version of ASTA, the combination of nonsteering and rotation of the coordinate system is also effective, because the lateral bandwidth does not decrease. In such a case, transmission of a laterally wide wave will also be effective, particularly for three-dimensional measurement/imaging using a two-dimensional array transducer. ASTA can also be used for accurate lateral displacement measurements. Although a proper beam steering and/or a proper coordinate rotation improves the

  18. Active Return-to-Center Control Based on Torque and Angle Sensors for Electric Power Steering Systems.

    Science.gov (United States)

    Du, Pan-Pan; Su, Hao; Tang, Gong-You

    2018-03-14

    This paper presents a complete control strategy of the active return-to-center (RTC) control for electric power steering (EPS) systems. We first establish the mathematical model of the EPS system and analyze the source and influence of the self-aligning torque (SAT). Second, based on the feedback signals of steering column torque and steering wheel angle, we give the trigger conditions of a state switch between the steering assist state and the RTC state. In order to avoid the sudden change of the output torque for the driving motor when the state switches frequently between the steering assist state and the RTC state, we design an undisturbed state switching logic algorithm. This state switching logic algorithm ensures that the output value of the RTC controller is set to an initial value and increases in given steps up to a maximum value after entering the RTC state, and the output value of the RTC controller will reduce in given steps down to zero when exiting the RTC state. This therefore ensures smooth switch control between the two states and improves the driver's steering feeling. Third, we design the RTC controller, which depends upon the feedback signals of the steering wheel angle and the angular velocity. In addition, the controller increases the auxiliary control function of the RTC torque based on vehicle speed. The experimental results show that the active RTC control method does not affect the basic assist characteristics, which effectively reduces the residual angle of the steering wheel at low vehicle speed and improves the RTC performance of the vehicle.

  19. Influence of slow-release urea on nitrogen balance and portal-drained visceral nutrient flux in beef steers

    DEFF Research Database (Denmark)

    Taylor-Edwards, C C; Elam, N A; Kitts, S E

    2009-01-01

    Two experiments were conducted to evaluate the effects of slow-release urea (SRU) versus feed-grade urea on portal-drained visceral (PDV) nutrient flux, nutrient digestibility, and total N balance in beef steers.......Two experiments were conducted to evaluate the effects of slow-release urea (SRU) versus feed-grade urea on portal-drained visceral (PDV) nutrient flux, nutrient digestibility, and total N balance in beef steers....

  20. Active Return-to-Center Control Based on Torque and Angle Sensors for Electric Power Steering Systems

    Directory of Open Access Journals (Sweden)

    Pan-Pan Du

    2018-03-01

    Full Text Available This paper presents a complete control strategy of the active return-to-center (RTC control for electric power steering (EPS systems. We first establish the mathematical model of the EPS system and analyze the source and influence of the self-aligning torque (SAT. Second, based on the feedback signals of steering column torque and steering wheel angle, we give the trigger conditions of a state switch between the steering assist state and the RTC state. In order to avoid the sudden change of the output torque for the driving motor when the state switches frequently between the steering assist state and the RTC state, we design an undisturbed state switching logic algorithm. This state switching logic algorithm ensures that the output value of the RTC controller is set to an initial value and increases in given steps up to a maximum value after entering the RTC state, and the output value of the RTC controller will reduce in given steps down to zero when exiting the RTC state. This therefore ensures smooth switch control between the two states and improves the driver’s steering feeling. Third, we design the RTC controller, which depends upon the feedback signals of the steering wheel angle and the angular velocity. In addition, the controller increases the auxiliary control function of the RTC torque based on vehicle speed. The experimental results show that the active RTC control method does not affect the basic assist characteristics, which effectively reduces the residual angle of the steering wheel at low vehicle speed and improves the RTC performance of the vehicle.

  1. Nutritional parameters of steers receiving different levels of sunflower crushed in partial replacement of soybean meal

    Directory of Open Access Journals (Sweden)

    HELLEN L. LIMA

    2013-10-01

    Full Text Available ABSTRACT To evaluate of the sunflower crushed in nutritional parameters in steers, supplemented at pasture, we used four steers in 4×4 Latin square design. The supplements were provided in 6 g/kg of body weight/animal/day, consisting of sunflower crushed, corn, soybean meal and mineral. All the supplements was isonitrogenous and soybean meal was replaced in 0, 20, 40, and 60% for sunflower crushed. The determination of ruminal pH and ammonia was at 0, 2, 4, 6 and 8 h. after feeding and for short-chain fatty acids it was collected at 0 and 6 h. post-feeding. The dry matter intake was not affected (P>0.05 by inclusion of sunflower crushed (mean=6.59 kg/day. There was no significant effect (P>0.05 for pH for the inclusion of sunflower crushed (mean=6.41. For contents of ruminal NH3-N was a significant effect (P <0.05 only for collection time, and ammonia peaks occurred between 2 and 4 h after feeding, with values of 22.56 and 21.40 mg/dL. The total concentration of short chain fatty acids and the C2:C3 ratio was reduced in 9.6 and 15.43%. The ruminal degradability of NDF was not affected by the supplements. The supplementation with sunflower crushed to beef steers grazing, in partial replacement of soybean meal did not alter nutrition parameters.

  2. Estimation of automobile-driver describing function from highway tests using the double steering wheel

    Science.gov (United States)

    Delp, P.; Crossman, E. R. F. W.; Szostak, H.

    1972-01-01

    The automobile-driver describing function for lateral position control was estimated for three subjects from frequency response analysis of straight road test results. The measurement procedure employed an instrumented full size sedan with known steering response characteristics, and equipped with a lateral lane position measuring device based on video detection of white stripe lane markings. Forcing functions were inserted through a servo driven double steering wheel coupling the driver to the steering system proper. Random appearing, Gaussian, and transient time functions were used. The quasi-linear models fitted to the random appearing input frequency response characterized the driver as compensating for lateral position error in a proportional, derivative, and integral manner. Similar parameters were fitted to the Gabor transformed frequency response of the driver to transient functions. A fourth term corresponding to response to lateral acceleration was determined by matching the time response histories of the model to the experimental results. The time histories show evidence of pulse-like nonlinear behavior during extended response to step transients which appear as high frequency remnant power.

  3. Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration

    International Nuclear Information System (INIS)

    Firkins, J.L.; Berger, L.L.; Merchen, N.R.; Fahey, G.C. Jr.; Mulvaney, R.L.

    1987-01-01

    Four multiple-cannulated steers (340 kg) were used in a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments. Steers were fed a diet of 50% ground hay and 50% concentrate at two intakes (1.4 and 2.1% of BW), with urea and 15 N-enriched ammonium sulfate infused continuously into the rumen at .4 or 1.2% of diet DM. Ratios of purines and diaminopimelic acid-N to N in fluid-associated and particulate-associated bacteria and in protozoa were similar among treatments but were lower for protozoa than for bacteria. Diaminopimelic acid-N:N was higher for fluid-associated vs. particulate-associated bacteria. Enrichment of 15 N was similar between bacteria among treatments and was 30% lower for protozoa. Turnover rates of 15 N in bacteria, NH 3 N, and non-HN 3 N pools were faster for steers infused with 1.2 than those infused with .4% urea, indicating less efficient usage of ammonia with higher urea. A method is described to estimate the proportion of duodenal nitrogen comprising bacterial and protozoal nitrogen

  4. Satellite guidance systems in agriculture: experimental comparison between EZ-Steer/RTK and AUTOPILOT/EGNOS

    Directory of Open Access Journals (Sweden)

    P. D’Antonio

    2013-09-01

    Full Text Available The research has been conducted using two different satellite-guidance devices and two different correction systems of the GPS signal: the EZ-Steer/RTK and Autopilot/EGNOS. The machines used in the tests were the tractor New Holland T7060, the rotary harrow Alpego DG-400 and the burier Forigo DG-45, in order to determine which of the two systems ensured the best quality of work. On the basis of the results obtained it is clear that the EZ-Steer/RTK system, guarantees a lower stability of the theoretical trajectory compared to the Autopilot/EGNOS system, above 1,77%. From the elaboration of data of the two guidance systems behavior to manage the only width of transposition, it is observed that the EZ-Steer/RTK system is able to guarantee a better hold of the line compared to the Autopilot/EGNOS system, which provides a mistake of 164 cm on the total width of transposition and 2 cm on the mean value. In the matter of the normalized transposition surfaces, the Autopilot/EGNOS system ensures a better work quality.

  5. The ATLAS High Level Trigger Configuration and Steering Software: Experience with 7 TeV Collisions

    CERN Document Server

    George, S; The ATLAS collaboration

    2010-01-01

    In 2010 ATLAS has seen the first proton-proton collisions at 7 TeV. Later this year a collision rate of nearly 10 MHz is expected. Events of potential interest for physics analysis are selected by a three-level trigger system, with a final recording rate of about 200 Hz. The first level (L1) is implemented in customised hardware, the two levels of the high level trigger (HLT) are software triggers. The selection is described by the Trigger Configuration in the form of menus, each of which contains more than 500 signatures. Each signature corresponds to a chain of algorithms which reconstruct and refine specific event features. The HLT Steering receives information from the Configuration system, dynamically creates chains and controls the execution of algorithms and flow of information during event processing. The Steering tests each signature on L1-accepted events, and those satisfying one or more test are recorded for later analysis. To save execution time, the Steering has a facility to cache results, avoid...

  6. The ATLAS High Level Trigger Configuration and Steering Software: Experience with 7 TeV Collisions

    CERN Document Server

    George, S; The ATLAS collaboration

    2010-01-01

    In 2010 ATLAS has seen the first proton-proton collisions at 7 TeV. Later this year a collision rate of nearly 10 MHz is expected. Events of potential interest for physics analysis are selected by a three-level trigger system, with a final recording rate of about 200 Hz. The first level (L1) is implemented in customized hardware, the two levels of the high level trigger (HLT) are software triggers. The selection is described by the Trigger Configuration in the form of menus, each of which contains more than 500 signatures. Each signature corresponds to a chain of algorithms which reconstruct and refine specific event features. The HLT Steering receives information from the Configuration system, dynamically creates chains and controls the execution of algorithms and flow of information during event processing. The Steering tests each signature on L1-accepted events, and those satisfying one or more test are recorded for later analysis. To save execution time, the Steering has a facility to cache results, avoid...

  7. A mathematical model for predicting lane changes using the steering wheel angle.

    Science.gov (United States)

    Schmidt, Kim; Beggiato, Matthias; Hoffmann, Karl Heinz; Krems, Josef F

    2014-06-01

    Positive safety effects of advanced driver assistance systems can only become effective if drivers accept and use these systems. Early detection of driver's intention would allow for selective system activation and therefore reduce false alarms. This driving simulator study aims at exploring early predictors of lane changes. In total, 3111 lane changes of 51 participants on a simulated highway track were analyzed. Results show that drivers stopped their engagement in a secondary task about 7s before crossing the lane, which indicates a first planning phase of the maneuver. Subsequently, drivers start moving toward the lane, marking a mean steering wheel angle of 2.5°. Steering wheel angle as a directly measurable vehicle parameter appears as a promising early predictor of a lane change. A mathematical model of the steering wheel angle is presented, which is supposed to contribute for predicting lane change maneuvers. The mathematical model will be part of a further predictor of lane changes. This predictor can be a new advanced driver assistance system able to recognize a driver's intention. With this knowledge, other systems can be activated or deactivated so drivers get no annoying and exhausting alarm signals. This is one way how we can increase the acceptance of assistance systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Optimal run-and-tumble-based transportation of a Janus particle with active steering.

    Science.gov (United States)

    Mano, Tomoyuki; Delfau, Jean-Baptiste; Iwasawa, Junichiro; Sano, Masaki

    2017-03-28

    Although making artificial micrometric swimmers has been made possible by using various propulsion mechanisms, guiding their motion in the presence of thermal fluctuations still remains a great challenge. Such a task is essential in biological systems, which present a number of intriguing solutions that are robust against noisy environmental conditions as well as variability in individual genetic makeup. Using synthetic Janus particles driven by an electric field, we present a feedback-based particle-guiding method quite analogous to the "run-and-tumbling" behavior of Escherichia coli but with a deterministic steering in the tumbling phase: the particle is set to the run state when its orientation vector aligns with the target, whereas the transition to the "steering" state is triggered when it exceeds a tolerance angle [Formula: see text] The active and deterministic reorientation of the particle is achieved by a characteristic rotational motion that can be switched on and off by modulating the ac frequency of the electric field, which is reported in this work. Relying on numerical simulations and analytical results, we show that this feedback algorithm can be optimized by tuning the tolerance angle [Formula: see text] The optimal resetting angle depends on signal to noise ratio in the steering state, and it is shown in the experiment. The proposed method is simple and robust for targeting, despite variability in self-propelling speeds and angular velocities of individual particles.

  9. Dispersion Free Steering for YASP and dispersion correction for TI8

    CERN Document Server

    Wenninger, J

    2009-01-01

    The LHC injection tests performed in August 2008 revealed a horizontal dispersion mismatch for both the TI2 and the TI8 transfer lines. While the error for TI2 is acceptable and most likely due to an error of the initial conditions at the entrance of the line, the TI8 dispersion error is rather severe. No unambiguous source of the dispersion mismatch could be identified, even tough large strength errors on some quadrupoles could explain part of the problem [1]. Steering and energy matching of both TI2 and TI8 are tricky due to the limited sampling of the trajectories by the beam position monitors. The possibility that the dispersion error may be due to the kicks from misaligned quadrupoles and from orbit correctors was pointed by E. Gianfelice and first tests yielded encouraging results [2]. The SPS and LHC steering program YASP was therefore upgraded to be able to perform combined orbit (or trajectory) and dispersion corrections, so called Dispersion Free Steering (DFS) that was already used at LEP [3]. This...

  10. Steering of sub-GeV electrons by ultrashort Si and Ge bent crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sytov, A.I. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; Belarusian State Univ., Minsk (Belarus). Inst. for Nuclear Problems; INFN Sezione di Ferrara (Italy); Bandiera, L.; Mazzolari, A.; Bagli, E.; Germogli, G.; Guidi, V.; Romagnoni, M. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; INFN Sezione di Ferrara (Italy); De Salvador, D.; Carturan, S.; Maggioni, G. [INFN, Laboratori Nazionali di Legnaro (Italy); Padova Univ. (Italy). Dipt. di Fisica; Berra, A.; Prest, M. [Univ. dell' Insubria, Como (Italy); INFN, Sezione di Milano Bicocca, Milan (Italy); Durighello, C. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; INFN, Laboratori Nazionali di Legnaro (Italy); Padova Univ. (Italy). Dipt. di Fisica; INFN Sezione di Ferrara (Italy); Klag, P.; Lauth, W. [Mainz Univ. (Germany). Inst. fuer Kernphysik; Tikhomirov, V.V. [Belarusian State Univ., Minsk (Belarus). Inst. for Nuclear Problems; Vallazza, E. [INFN, Sezione di Trieste (Italy)

    2017-12-15

    We report the observation of the steering of 855 MeV electrons by bent silicon and germanium crystals at the MAinzer MIkrotron. Crystals with 15 μm of length, bent along (111) planes, were exploited to investigate orientational coherent effects. By using a piezo-actuated mechanical holder, which allowed to remotely change the crystal curvature, it was possible to study the steering capability of planar channeling and volume reflection vs. the curvature radius and the atomic number, Z. For silicon, the channeling efficiency exceeds 35%, a record for negatively charged particles. This was possible due to the realization of a crystal with a thickness of the order of the dechanneling length. On the other hand, for germanium the efficiency is slightly below 10% due to the stronger contribution of multiple scattering for a higher-Z material. Nevertheless this is the first evidence of negative beam steering by planar channeling in a Ge crystal. Having determined for the first time the dechanneling length, one may design a Ge crystal based on such knowledge providing nearly the same channeling efficiency of silicon. The presented results are relevant for crystal-based beam manipulation as well as for the generation of e.m. radiation in bent and periodically bent crystals. (orig.)

  11. Automated vehicle guidance using discrete reference markers. [road surface steering techniques

    Science.gov (United States)

    Johnston, A. R.; Assefi, T.; Lai, J. Y.

    1979-01-01

    Techniques for providing steering control for an automated vehicle using discrete reference markers fixed to the road surface are investigated analytically. Either optical or magnetic approaches can be used for the sensor, which generates a measurement of the lateral offset of the vehicle path at each marker to form the basic data for steering control. Possible mechanizations of sensor and controller are outlined. Techniques for handling certain anomalous conditions, such as a missing marker, or loss of acquisition, and special maneuvers, such as u-turns and switching, are briefly discussed. A general analysis of the vehicle dynamics and the discrete control system is presented using the state variable formulation. Noise in both the sensor measurement and in the steering servo are accounted for. An optimal controller is simulated on a general purpose computer, and the resulting plots of vehicle path are presented. Parameters representing a small multipassenger tram were selected, and the simulation runs show response to an erroneous sensor measurement and acquisition following large initial path errors.

  12. Steering of Sub-GeV electrons by ultrashort Si and Ge bent crystals

    Science.gov (United States)

    Sytov, A. I.; Bandiera, L.; De Salvador, D.; Mazzolari, A.; Bagli, E.; Berra, A.; Carturan, S.; Durighello, C.; Germogli, G.; Guidi, V.; Klag, P.; Lauth, W.; Maggioni, G.; Prest, M.; Romagnoni, M.; Tikhomirov, V. V.; Vallazza, E.

    2017-12-01

    We report the observation of the steering of 855 MeV electrons by bent silicon and germanium crystals at the MAinzer MIkrotron. Crystals with 15 μ m of length, bent along (111) planes, were exploited to investigate orientational coherent effects. By using a piezo-actuated mechanical holder, which allowed to remotely change the crystal curvature, it was possible to study the steering capability of planar channeling and volume reflection vs. the curvature radius and the atomic number, Z. For silicon, the channeling efficiency exceeds 35%, a record for negatively charged particles. This was possible due to the realization of a crystal with a thickness of the order of the dechanneling length. On the other hand, for germanium the efficiency is slightly below 10% due to the stronger contribution of multiple scattering for a higher-Z material. Nevertheless this is the first evidence of negative beam steering by planar channeling in a Ge crystal. Having determined for the first time the dechanneling length, one may design a Ge crystal based on such knowledge providing nearly the same channeling efficiency of silicon. The presented results are relevant for crystal-based beam manipulation as well as for the generation of e.m. radiation in bent and periodically bent crystals.

  13. Human-robot collaborated path planning for bevel-tip needle steering in simulated human environment.

    Science.gov (United States)

    Jing Xiong; Zeyang Xia; Yangzhou Gan

    2016-08-01

    Clinical Application of linear percutaneous needle insertion is restricted due to issues such as limited path and deflection. Thus steering of flexible needle is critical demanded in the clinic. Previous studies tended to use autonomous methods to conduct path planning for needle steering. However, these methods had very limited adaptabilities, and they also decreased the human operator's domination of the operation, as clinically required. In this case, teleoperation has been an option, while in complicated environments sole teleoperation is not sufficient for a human operator to generate multi-curved insertion path. Therefore, in this paper, we propose a semiautonomous human-robot collaborated path planning method for teleoperated bevel-tip needle steering. The key module of this method is a human-robot collaboration mechanism which consists of the operator input, environment constraints, and path constraints. The proposed method were tested semi-physically in a simulated human environment and the results validated that the proposed method were able to efficiently assist the operator to generate multi-curved paths under human operator's domination.

  14. Control order and visuomotor strategy development for joystick-steered underground shuttle cars.

    Science.gov (United States)

    Cloete, Steven; Zupanc, Christine; Burgess-Limerick, Robin; Wallis, Guy

    2014-09-01

    In this simulator-based study, we aimed to quantify performance differences between joystick steering systems using first-order and second-order control, which are used in underground coal mining shuttle cars. In addition, we conducted an exploratory analysis of how users of the more difficult, second-order system changed their behavior over time. Evidence from the visuomotor control literature suggests that higher-order control devices are not intuitive, which could pose a significant risk to underground mine personnel, equipment, and infrastructure. Thirty-six naive participants were randomly assigned to first- and second-order conditions and completed three experimental trials comprising sequences of 90 degrees turns in a virtual underground mine environment, with velocity held constant at 9 km/h(-1). Performance measures were lateral deviation, steering angle variability, high-frequency steering content, joystick activity, and cumulative time in collision with the virtual mine wall. The second-order control group exhibited significantly poorer performance for all outcome measures. In addition, a series of correlation analyses revealed that changes in strategy were evident in the second-order group but not the first-order group. Results were consistent with previous literature indicating poorer performance with higher-order control devices and caution against the adoption of the second-order joystick system for underground shuttle cars. Low-cost, portable simulation platforms may provide an effective basis for operator training and recruitment.

  15. A Time Modulated Printed Dipole Antenna Array for Beam Steering Application

    Directory of Open Access Journals (Sweden)

    Ruchi Gahley

    2017-01-01

    Full Text Available This paper presents time modulated beam steered antenna array without phase shifters. The beam steering is analyzed considering a two-element time modulated antenna array (TMAA of printed dipoles with microstrip via-hole balun. The proposed array resonates at the Industrial, Scientific, and Medical (ISM radio bands, 2.45 GHz and 5.8 GHz, and offers wide bandwidth inherited due to modified structure of ground plane. Array elements are excited by complex exponential excitation signal through broadband power divider and radio frequency (RF switches to achieve amplitude and phase variation without phase shifters. Differential Evolution algorithm is used to modify the time sequences of the RF switches connected to the antennas to generate radiation pattern with optimum dynamic efficiency by suppressing sideband radiations. Also switch-on time instant of RF switch connected to the subsequent element is modulated to steer the beam towards different directions. The proposed prototype is fabricated followed by parametric optimization. The fabrication results agree significantly well with simulated results.

  16. Development of the ATLAS High-Level Trigger Steering and Inclusive Searches for Supersymmetry

    CERN Document Server

    Eifert, T

    2009-01-01

    The presented thesis is divided into two distinct parts. The subject of the first part is the ATLAS high-level trigger (HLT), in particular the development of the HLT Steering, and the trigger user-interface. The second part presents a study of inclusive supersymmetry searches, including a novel background estimation method for the relevant Standard Model (SM) processes. The trigger system of the ATLAS experiment at the Large Hadron Collider (LHC) performs the on-line physics selection in three stages: level-1 (LVL1), level-2 (LVL2), and the event filter (EF). LVL2 and EF together form the HLT. The HLT receives events containing detector data from high-energy proton (or heavy ion) collisions, which pass the LVL1 selection at a maximum rate of 75 kHz. It must reduce this rate to ~200 Hz, while retaining the most interesting physics. The HLT is a software trigger and runs on a large computing farm. At the heart of the HLT is the Steering software. The HLT Steering must reach a decision whether or not to accept ...

  17. Effects of Student-Facilitated Learning on Instructional Facilitators

    Science.gov (United States)

    Bonner, Sarah M.; Somers, Jennifer A.; Rivera, Gwendelyn J.; Keiler, Leslie S.

    2017-01-01

    We investigated perceptions about learning strategy use and instructional roles among a sample of high needs adolescents (n = 230) who acted as near-peer instructional facilitators. The sample was drawn from science and mathematics classes in nonselective public secondary schools in New York City. Students participated in an inschool intervention…

  18. Facilitation of learning: part 1.

    Science.gov (United States)

    Warburton, Tyler; Trish, Houghton; Barry, Debbie

    2016-04-06

    This article, the fourth in a series of 11, discusses the context for the facilitation of learning. It outlines the main principles and theories for understanding the process of learning, including examples which link these concepts to practice. The practical aspects of using these theories in a practice setting will be discussed in the fifth article of this series. Together, these two articles will provide mentors and practice teachers with knowledge of the learning process, which will enable them to meet the second domain of the Nursing and Midwifery Council's Standards to Support Learning and Assessment in Practice on facilitation of learning.

  19. Performance of finishing beef steers in response to anabolic implant and zilpaterol hydrochloride supplementation.

    Science.gov (United States)

    Parr, S L; Chung, K Y; Galyean, M L; Hutcheson, J P; DiLorenzo, N; Hales, K E; May, M L; Quinn, M J; Smith, D R; Johnson, B J

    2011-02-01

    Our objectives were to evaluate the dose/payout pattern of trenbolone acetate (TBA) and estradiol-17β (E(2)) implants and feeding of zilpaterol hydrochloride (ZH) on performance and carcass characteristics of finishing beef steers. A randomized complete block design was used with a 3 × 2 factorial arrangement of treatments. British × Continental steers (n = 168; initial BW = 362 kg) were blocked by BW and allotted randomly to 42 pens (7 pens/treatment; 6 pens/block; 4 steers/pen). The main effects of treatment were implant [no implant (NI); Revalor-S (REV-S; 120 mg of TBA + 24 mg of E(2)); and Revalor-XS (REV-X; 200 mg of TBA + 40 mg of E(2))] and ZH (0 or 8.3 mg/kg of DM for 20 d with a 3-d withdrawal before slaughter). Blocks were split into 2 groups, and block groups were fed for either 153 or 174 d. No implant × ZH interactions were noted for cumulative performance data. Overall, shrunk final BW (567, 606, and 624 kg for NI, REV-S, and REV-X, respectively), ADG (1.25, 1.51, and 1.60 kg), and G:F (0.14, 0.16, and 0.17) increased (P 0.10) between REV-S and REV-X (8.8 for NI vs. 9.4 kg/d for the 2 implants). From d 1 to 112 of the feeding period, implanting increased (P 0.10). From d 112 to end, ADG increased by 19% (P 0.10) between REV-X and REV-S. With ZH, REV-X increased (1.7%; P 0.10) by implant or ZH. Overall, treatment increased steer performance and HCW in an additive fashion, suggesting different mechanisms of action for ZH and steroidal implants. In addition, a greater dose of TBA + E(2) and extended payout improved steer performance and HCW.

  20. Social Facilitation of Aiding Responses.

    Science.gov (United States)

    Bartell, Patricia; And Others

    Research on individual's response to emergency situations in the presence of others has produced conflicting results. The bystander effect is the label applied to inaction or the unlikelihood of assistance with others present. The social facilitation effect occurs when the presence of others energizes response; strong habit responses are…

  1. Brug af mindfulness til facilitering

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2011-01-01

    Gennem de senere år er mindfulness gået fra udelukkende at være en eksistentiel praksis til også at være en behandlingsform og senest til også at blive brugt som et praktisk redskab i erhvervslivet. Denne artikel viser, at mindfulness også kan anvendes i forbindelse med facilitering. Facilitering...... er et værktøj, som bruges i arbejdslivet fx til møder og konferencer, hvor en gruppe mennesker er samlet for at lære eller udrette noget sammen. Det nye ved at kombinere mindfulness med facilitering er, at fokus hermed ændres fra individet, som er centrum for den eksistentielle fordybelse eller det...... terapeutiske forløb, til gruppen, som er udgangspunktet i facilitering. Artiklen viser, hvordan mindfulness konkret kan bruges på gruppeniveau og diskuterer samtidig hvilke problemer, der kan være forbundet hermed. Baseret på vores egne erfaringer, diskuterer vi, hvordan mindfulness kan påvirke en gruppes...

  2. Facilitation of Mourning During Childhood.

    Science.gov (United States)

    Kliman, Gilbert; And Others

    This paper discusses case studies of children psychologically disturbed by the death of parents or siblings. Illustrations of mourning facilitation were mainly gathered from 16 orphaned children, ages 3-14. Some techniques used in helping children mourn include: discussing physical details of the illness, discussing previous deaths of animals and…

  3. Performance and welfare of steers housed on concrete slatted floors at fixed and dynamic (allometric based) space allowances.

    Science.gov (United States)

    Keane, Michael P; McGee, Mark; O'Riordan, Edward G; Kelly, Alan K; Earley, Bernadette

    2018-04-03

    The objectives of the study were to determine whether allometric equations are suitable for estimating the space requirements of finishing beef cattle housed on concrete slatted floors (CSF) and to examine the effect of fixed and dynamic space allowances on the performance and welfare of these cattle. Continental crossbred steers [n = 120: mean initial live weight, 590 (SD 29.8) kg] were blocked by breed, weight, and age and assigned to 1 of 5 space allowance treatments (3 fixed and 2 dynamic) on CSF: 1) 2.0 m2 per animal, 2) 2.5 m2 per animal, 3) 3.0 m2 per animal, 4) Equation 1 (E1); y = 0.033w0.667, where y = m2 per animal and w = body weight, and 5) Equation 2 (E2); y = 0.048w0.667. The length of the feed face was 3.0 m for all treatments. Steers were offered grass silage and concentrates ad libitum. DMI was recorded weekly on a pen basis. Steers were weighed and dirt scored every 14 d. Blood samples were collected every 28 d, and analyzed for complete cell counts. Behavior was recorded using closed-circuit infrared cameras. Steers' hooves were inspected for lesions at the beginning of the study and post-slaughter. Slaughter weight and ADG were lowest, and feed conversion ratio (FCR) was poorest, for steers accommodated at 2.0 m2, and slaughter weight and ADG were greatest, and FCR was the best, for steers accommodated at E2 (P 0.05) to those accommodated at 2.0 m2 and both 3.0 m2 and E1, whereas steers accommodated at 3.0 m2 and E1 were intermediate (P > 0.05) to 2.5 m2 and E2. Carcass weight of steers housed at 2.0 m2 was lower (P < 0.05) than all other treatments. Steers housed at 2.5 m2 had lower carcass weights (P < 0.05) than those with accommodated at E1 and E2, whereas the carcass weight of steers accommodated at 3.0 m2 was intermediate. Carcass fat scores and hide weights were lower (P < 0.05) in steers accommodated at 2.0 m2 than those housed at E2 with other treatments being intermediate. The number of steers lying at any one time and the number of

  4. Investigating Einstein-Podolsky-Rosen steering of continuous-variable bipartite states by non-Gaussian pseudospin measurements

    Science.gov (United States)

    Xiang, Yu; Xu, Buqing; Mišta, Ladislav; Tufarelli, Tommaso; He, Qiongyi; Adesso, Gerardo

    2017-10-01

    Einstein-Podolsky-Rosen (EPR) steering is an asymmetric form of correlations which is intermediate between quantum entanglement and Bell nonlocality, and can be exploited as a resource for quantum communication with one untrusted party. In particular, steering of continuous-variable Gaussian states has been extensively studied theoretically and experimentally, as a fundamental manifestation of the EPR paradox. While most of these studies focused on quadrature measurements for steering detection, two recent works revealed that there exist Gaussian states which are only steerable by suitable non-Gaussian measurements. In this paper we perform a systematic investigation of EPR steering of bipartite Gaussian states by pseudospin measurements, complementing and extending previous findings. We first derive the density-matrix elements of two-mode squeezed thermal Gaussian states in the Fock basis, which may be of independent interest. We then use such a representation to investigate steering of these states as detected by a simple nonlinear criterion, based on second moments of the correlation matrix constructed from pseudospin operators. This analysis reveals previously unexplored regimes where non-Gaussian measurements are shown to be more effective than Gaussian ones to witness steering of Gaussian states in the presence of local noise. We further consider an alternative set of pseudospin observables, whose expectation value can be expressed more compactly in terms of Wigner functions for all two-mode Gaussian states. However, according to the adopted criterion, these observables are found to be always less sensitive than conventional Gaussian observables for steering detection. Finally, we investigate continuous-variable Werner states, which are non-Gaussian mixtures of Gaussian states, and find that pseudospin measurements are always more effective than Gaussian ones to reveal their steerability. Our results provide useful insights on the role of non

  5. Facilitating Facilitators to Facilitate, in Problem or Enquiry Based Learning Sessions

    Science.gov (United States)

    Coelho, Catherine

    2014-01-01

    Problem based learning (PBL) has been used in dental education over the past 20 years and uses a patient case scenario to stimulate learning in a small group setting, where a trained facilitator does not teach but guides the group to bring about deep contextualized learning, to be empathetic to each other and to encourage fair and equitable…

  6. In vivo facilitated diffusion model.

    Directory of Open Access Journals (Sweden)

    Maximilian Bauer

    Full Text Available Under dilute in vitro conditions transcription factors rapidly locate their target sequence on DNA by using the facilitated diffusion mechanism. However, whether this strategy of alternating between three-dimensional bulk diffusion and one-dimensional sliding along the DNA contour is still beneficial in the crowded interior of cells is highly disputed. Here we use a simple model for the bacterial genome inside the cell and present a semi-analytical model for the in vivo target search of transcription factors within the facilitated diffusion framework. Without having to resort to extensive simulations we determine the mean search time of a lac repressor in a living E. coli cell by including parameters deduced from experimental measurements. The results agree very well with experimental findings, and thus the facilitated diffusion picture emerges as a quantitative approach to gene regulation in living bacteria cells. Furthermore we see that the search time is not very sensitive to the parameters characterizing the DNA configuration and that the cell seems to operate very close to optimal conditions for target localization. Local searches as implied by the colocalization mechanism are only found to mildly accelerate the mean search time within our model.

  7. Effects of ractopamine and sex on serum metabolites and skeletal muscle gene expression in finishing steers and heifers.

    Science.gov (United States)

    Walker, D K; Titgemeyer, E C; Baxa, T J; Chung, K Y; Johnson, D E; Laudert, S B; Johnson, B J

    2010-04-01

    We evaluated growth-related responses to ractopamine in steers and heifers. Sixteen Angus steers (512 kg) and 16 Angus heifers (473 kg) housed in individual pens were used in a complete block design. At 90 to 97 d before the experiment, steers were implanted with 120 mg of trenbolone acetate and 24 mg of estradiol-17beta (Component TE-S) and heifers were implanted with 140 mg of trenbolone acetate and 14 mg of estradiol-17beta (Component TE-H). Treatments were arranged as a 2 x 2 factorial and included sex (steer vs. heifer) and ractopamine-HCl (0 or 200 mg/d). Cattle were fed a diet based on steam-flaked corn once daily. Blood and LM and biceps femoris (BF) biopsy samples were collected on d 0 (before ractopamine feeding) and after 14 and 28 d of ractopamine feeding. Serum insulin concentrations were not affected by ractopamine or sex. Serum IGF-I concentrations were greater in steers than heifers (P Ractopamine decreased serum IGF-I concentrations in heifers on d 14, but increased serum IGF-I concentrations in steers on d 28 (sex x ractopamine x day interaction; P = 0.03). Ractopamine did not affect (P >or= 0.19) mRNA expression of IGF-I, IGFBP-3, or calpastatin in BF or LM. However, ractopamine led to increases in LM expression of IGFBP-5 in heifers, but to decreases in expression in steers (ractopamine x sex interaction; P = 0.04). Ractopamine decreased myosin heavy chain IIA mRNA expression in BF (P = 0.04) but not in LM (P = 0.99). Ractopamine decreased beta(2)-receptor mRNA expression in LM of steers on d 14, but not on d 28; in contrast, expression of beta(2)-receptor mRNA in LM of heifers was not affected by ractopamine (sex x ractopamine x day interaction; P = 0.03). Although there were a few criteria for which ractopamine led to differences in response between steers and heifers, there were no striking disparities to suggest that the effectiveness of ractopamine would markedly differ between sexes.

  8. Impact of a leptin single nucleotide polymorphism and ractopamine hydrochloride on growth and carcass characteristics in finishing steers.

    Science.gov (United States)

    Kononoff, P J; Defoor, P J; Engler, M J; Swingle, R S; James, S T; Marquess, F L S

    2014-06-01

    A total of 2,958 steers (mean initial BW = 549.6 ± 3.88 kg) were used to test for the interactive effects, of leptin R25C genotypes (CC, CT, or TT) and feeding of ractopamine hydrochloride (RH) on growth performance and carcass traits. Before application of the drug, steers were blocked by arrival at the feed yard, genotyped for the leptin SNP, allotted to genotype-specific pens, and assigned randomly within genotype and block to 0 or 28 d of dietary RH. All pens within a block were slaughtered on the same day. Final BW of steers fed RH was 9.1 kg heavier (P < 0.001), and RH-fed steers had greater (P < 0.001) ADG and greater (P = 0.001) HCW than steers not fed RH. Feeding RH did not (P = 0.723) affect DMI but it did increase (P = 0.001) with increased frequency of the T allele (8.62, 8.70, and 8.82 kg/d for CC, CT, and TT, respectively). Consistent with the effect of leptin on DMI, increased frequency of the T allele also positively affected 12th rib fat (P = 0.001) and empty body fat (P = 0.001). Regardless of RH-feeding duration, TT steers produced a greater (P = 0.001) percentage of USDA yield grade (YG) 4 or higher carcasses (6.46 vs. 2.98%) and a lesser (P = 0.023) percentage of YG 1 carcasses (16.0 vs. 21.9%) than CC steers. In addition, RH-fed steers produced a lesser (P = 0.034) percentage of USDA YG 4 or higher carcasses (3.70 vs. 5.31%) and a lesser percentage (P = 0.019) of USDA Choice or higher carcasses (57.5 vs. 62.5%) than steers fed the control diet. Results indicated that leptin R25C genotype impacted most traits associated with fatness, whereas feeding RH for 28 d affected HCW and ADG positively but impacted marbling and USDA quality grades negatively.

  9. The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil

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    Seong Ho Choi

    2016-03-01

    Full Text Available We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD gene expression in subcutaneous (s.c. and intramuscular (i.m. adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control, with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα and peroxisome proliferator-activated receptor gamma (PPARγ increased between the initial and intermediate biopsies and declined thereafter (p<0.03. SCD gene expression did not change between the initial and intermediate biopsies but declined by over 75% by the final period (p = 0.04, and G-coupled protein receptor 43 (GPR43 gene expression was unaffected by diet or time on trial. Soybean oil decreased (p = 0.01 PPARγ gene expression at the intermediate sample time. At the terminal sample time, PPARγ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (p<0.05. AMPKα gene expression was less in s.c. adipose tissue of palm oil-fed steers than in control steers (p = 0.04 and CCAAT enhancer binding protein-beta (CEBPβ gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (p<0.03. Soybean oil decreased SCD gene expression in s.c. adipose tissue (p = 0.05; SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers

  10. Effect of alcohol dehydrogenase 1C (ADH1C genotype on vitamin A restriction and marbling in Korean native steers

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    Dong Qiao Peng

    2017-08-01

    Full Text Available Objective This work was to find the correlation of alcohol dehydrogenase 1C (ADH1C genotype with vitamin A reduction and carcass traits during the vitamin A restriction period. Methods In study 1, 60 Korean native steers were fed a diet (890 IU/kg with 8,000 IU and 0 IU of supplemental premix vitamin A/kg of dry matter (DM for control and treatment group, respectively. The levels of serum vitamin A were analyzed through high preparative performance liquid chromatography, and the ADH1C genotype was analyzed based on polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP; 78.1% TT type, 21.9% TC type; however, CC type was not found. Then, the interaction between ADH1C and carcass traits on the vitamin A restriction was investigated in study 2. A total of 136 Korean native steers were fed a diet that included 930 IU/kg vitamin A of DM. Results Serum vitamin A in treatment was reduced to 112.4 IU/dL in steers with TT type of ADH1C, while for steers with TC type the concentration of serum vitamin A was dropped to 79.5 IU/dL (p<0.1 in study 1. This showed that TC type had the potential to lower serum vitamin A concentration during vitamin A restriction compared to TT type. In study 2 we found that eye muscle area, marbling and carcass weight in Korean native steers with TC type were higher than in steers with TT type (p<0.05. Conclusion The interaction between vitamin A restriction and TC type of ADH1C gene could have the potential of increasing the marbling in Korean native steers. These results indicated that steers with TC type of the ADH1C gene were more sensitive to the change of serum vitamin A than TT types. Furthermore, this finding has the potential to enable a higher marbling score under the condition of vitamin A restriction in Korean native steers.

  11. Relationships among Ergot Alkaloids, Cytochrome P450 Activity, and Beef Steer Growth

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    Rosenkrans, Charles; Ezell, Nicholas

    2015-03-01

    Determining a grazing animal’s susceptibility to ergot alkaloids has been a research topic for decades. Our objective was to determine if the Promega™ P450-Glo assay could be used to indirectly detect ergot alkaloids or their metabolites in urine of steers. The first experiment validated the effects of ergot alkaloids [0, 20, and 40 μM of ergotamine (ET), dihydroergotamine (DHET), and ergonovine (EN)] on human CYP3A4 using the P450-Glo assay (Promega™ V9800). With this assay, luminescence is directly proportional to CYP450 activity. Relative inhibition of in vitro cytochrome P450 activity was affected (P age; 203 ± 1.7 kg) after grazing tall fescue pastures for 105 d. Non-diluted urine was added to the Promega™ P450-Glo assay, and observed inhibition (3.7 % ± 2.7 of control). Urine content of total ergot alkaloids (331.1 ng/mg of creatinine ± 325.7) was determined using enzyme linked immunosorbent assay. Urine inhibition of CYP450 activity and total alkaloids were correlated (r = -0.31; P affected (P < 0.03) inhibition of CYP450 activity by urine; heterozygous steers had the least amount of CYP450 inhibition suggesting that genotyping cattle may be a method of identifying animals that are susceptible to ergot alkaloids. Although, additional research is needed, we demonstrate that the Promega™ P450-Glo assay is sensitive to ergot alkaloids and urine from steers grazing tall fescue. With some refinement the P450-Glo assay has potential as a tool for screening cattle for their exposure to fescue toxins.

  12. The effects of different flooring types on the behavior, health, and welfare of finishing beef steers.

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    Elmore, M R P; Elischer, M F; Claeys, M C; Pajor, E A

    2015-03-01

    Raising beef cattle on concrete floors can negatively impact their welfare by increasing joint swelling and body lesions, as well as abnormalities in resting behavior and postural changes. We hypothesized that the addition of rubber mats to concrete pens would improve beef cattle welfare by improving performance, health, hygiene, and resting behavior. Forty-eight crossbred Angus steers were housed in pens of 4 and randomly assigned to a single flooring treatment: (1) fully slatted concrete (CON), (2) fully slatted rubber mat (SLAT), or (3) solid rubber mat (SOLID; 60% of pen floor) from 36 to 48 wk of age. Weight, ADG, lesions, gait score, joint swelling, and animal and pen cleanliness were collected every 2 wk. Behavioral time budgets and frequency of postural changes (an indicator of floor traction and comfort) were collected at 0, 6, and 12 wk. No differences in weight gain or ADG were observed. Steers on SOLID flooring (0.80 ± 0.08) showed increased lesions compared to SLAT (0.38 ± 0.08) and CON (0.37 ± 0.08; both, = 0.05); however, there was no difference between SLAT and CON. SLAT steers (1.69 ± 0.04) showed a reduced gait score compared to SOLID (1.95 ± 0.04) and CON (1.98 ± 0.04; both, posture more frequently than those on SOLID and CON flooring (both, postural changes. Combined, these data suggest that the addition of slatted rubber mats to concrete pens may improve beef cattle welfare.

  13. Effect of Travel Speed on the Visual Control of Steering Toward a Goal.

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    Chen, Rongrong; Niehorster, Diederick C; Li, Li

    2017-08-17

    Previous studies have proposed that people can use visual cues such as the instantaneous direction (i.e., heading) or future path trajectory of travel specified by optic flow or target visual direction in egocentric space to steer or walk toward a goal. In the current study, we examined what visual cues people use to guide their goal-oriented locomotion and whether their reliance on such visual cues changes as travel speed increases. We presented participants with optic flow displays that simulated their self-motion toward a target at various travel speeds under two viewing conditions in which we made target egocentric direction available or unavailable for steering. We found that for both viewing conditions, participants did not steer along a curved path toward the target such that the actual and the required path curvature to reach the target would converge when approaching the target. At higher travel speeds, participants showed a faster and larger reduction in target-heading angle and more accurate and precise steady-state control of aligning their heading specified by optic flow with the target. These findings support the claim that people use heading and target egocentric direction but not path for goal-oriented locomotion control, and their reliance on heading increases at higher travel speeds. The increased reliance on heading for goal-oriented locomotion control could be due to an increased reliability in perceiving heading from optic flow as the magnitude of flow increases with travel speed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  14. Performance and carcass characteristics of dairy steers fed diets containing crude glycerin

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    Raylon Pereira Maciel

    Full Text Available ABSTRACT The objective of the study was to assess the effects of including 0, 79.8, 159.8, and 240.0 g kg-1 crude glycerin in the total diet dry matter on the 84 days feedlot performance, nutrient digestibility, blood parameters, and carcass characteristics of crossbred dairy steers. Experimental diets were composed of 98.5 g kg-1 of sorghum silage and 901.5 g kg-1 of concentrate. Twenty-four crossbred dairy steers (337.3±39.8 kg body weight and 15 months of age were distributed in a completely randomized design with four treatments and six replicates. The intake and digestibility of the dry matter and nutrients were not altered by including crude glycerin in the diet. Crude glycerol levels did not affect the final weight (430.2 kg, daily weight gain (1.38 kg day-1, total weight gain (97.2 kg, hot carcass weight (218.9 kg, cold carcass weight (215.2 kg, hot carcass yield (0.50 kg 100 kg-1 BW, longissimus dorsi area (62.86 cm², subcutaneous fat thickness (4.05 mm, and carcass physical composition. Concentrations of serum glucose, triglycerides, total cholesterol, high-density lipoprotein cholesterol, and creatinine were not altered by including crude glycerin in the diet. Crude glycerin can be added to high concentrate diet up to 240 g kg-1 without changing the animal performance, apparent digestibility of nutrients, the main carcass characteristics, and blood parameters of finishing crossbred dairy steers.

  15. Interactive visual steering--rapid visual prototyping of a common rail injection system.

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    Matković, Kresimir; Gracanin, Denis; Jelović, Mario; Hauser, Helwig

    2008-01-01

    Interactive steering with visualization has been a common goal of the visualization research community for twenty years, but it is rarely ever realized in practice. In this paper we describe a successful realization of a tightly coupled steering loop, integrating new simulation technology and interactive visual analysis in a prototyping environment for automotive industry system design. Due to increasing pressure on car manufacturers to meet new emission regulations, to improve efficiency, and to reduce noise, both simulation and visualization are pushed to their limits. Automotive system components, such as the powertrain system or the injection system have an increasing number of parameters, and new design approaches are required. It is no longer possible to optimize such a system solely based on experience or forward optimization. By coupling interactive visualization with the simulation back-end (computational steering), it is now possible to quickly prototype a new system, starting from a non-optimized initial prototype and the corresponding simulation model. The prototyping continues through the refinement of the simulation model, of the simulation parameters and through trial-and-error attempts to an optimized solution. The ability to early see the first results from a multidimensional simulation space--thousands of simulations are run for a multidimensional variety of input parameters--and to quickly go back into the simulation and request more runs in particular parameter regions of interest significantly improves the prototyping process and provides a deeper understanding of the system behavior. The excellent results which we achieved for the common rail injection system strongly suggest that our approach has a great potential of being generalized to other, similar scenarios.

  16. Intake and performance of steers fed with soybean dreg in confinement

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    Álisson Marian Callegaro

    2015-07-01

    Full Text Available This study was designed to evaluate the feasibility of using soybean dreg in finishing of confined steers, with age and initial body weight of 20 months and 328.3 kg, respectively. Each treatment consisted of six experimental animals, which were fed with forage: concentrate ratio, 40:60 (dry matter basis, being bulky corn silage and concentrate based of bark, chaff and soybean dreg, corn, sodium chloride and calcium limestone. The steers were distributed in the treatments: 00, 30, 60, 90 and 120 g of soybean dreg per kg of dry matter in the diet, which contained 29.0, 47.3, 66.7, 86.8 and 106.8 g of ether extract, respectively. The dry matter intake was similar (P> 0.05 among the studied treatments with an average of 9.71 kg day-1. Similarly, no differences were observed (P> 0.05 in crude protein intake with anaverage of 1.36 kg day-1. However, there were differences in the consumption of ether extract and neutral and acid detergent fibre, which decreased linearly with the increase in the inclusion of dreg in the diet (CEE=0,305+0,0061SD; CFDN=5.71–0,011SD; CFDA=3.89–0.008SD kg day-1, respectively. The performance of steers was similar (P>0.05 between treatments, being the average daily gain of 1.542 kg, the fed conversion of 6.35 kg DM kg-1 weight gain and slaughter weight of 457.95 kg. The use of soybean dreg until the limit of 120 g kg-1 in the diet of confined cattle is feasible.

  17. On-demand acoustic droplet splitting and steering in a disposable microfluidic chip.

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    Park, Jinsoo; Jung, Jin Ho; Park, Kwangseok; Destgeer, Ghulam; Ahmed, Husnain; Ahmad, Raheel; Sung, Hyung Jin

    2018-01-30

    On-chip droplet splitting is one of the fundamental droplet-based microfluidic unit operations to control droplet volume after production and increase operational capability, flexibility, and throughput. Various droplet splitting methods have been proposed, and among them the acoustic droplet splitting method is promising because of its label-free operation without any physical or thermal damage to droplets. Previous acoustic droplet splitting methods faced several limitations: first, they employed a cross-type acoustofluidic device that precluded multichannel droplet splitting; second, they required irreversible bonding between a piezoelectric substrate and a microfluidic chip, such that the fluidic chip was not replaceable. Here, we present a parallel-type acoustofluidic device with a disposable microfluidic chip to address the limitations of previous acoustic droplet splitting devices. In the proposed device, an acoustic field is applied in the direction opposite to the flow direction to achieve multichannel droplet splitting and steering. A disposable polydimethylsiloxane microfluidic chip is employed in the developed device, thereby removing the need for permanent bonding and improving the flexibility of the droplet microfluidic device. We experimentally demonstrated on-demand acoustic droplet bi-splitting and steering with precise control over the droplet splitting ratio, and we investigated the underlying physical mechanisms of droplet splitting and steering based on Laplace pressure and ray acoustics analyses, respectively. We also demonstrated droplet tri-splitting to prove the feasibility of multichannel droplet splitting. The proposed on-demand acoustic droplet splitting device enables on-chip droplet volume control in various droplet-based microfluidic applications.

  18. Effects of channel constriction on upstream steering of flow around Locke Island, Columbia River, Washington

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    Loy, G. E.; Furbish, D. J.; Covey, A.

    2010-12-01

    Landsliding of the White Bluffs along the Columbia River in Washington State has constricted the width of the river on one side of Locke Island, a two-kilometer long island positioned in the middle of the channel. Associated changes in flow are thought to be causing relatively rapid erosion of Locke Island on the constricted side. This island is of cultural significance to Native American tribes of south-central Washington, so there are social as well as scientific reasons to understand how the alteration of stream channel processes resulting from the landsliding might be influencing observed erosion rates. Simple hydrodynamic calculations suggest that the constriction on one side of the island creates an upstream backwater effect. As a consequence a cross-stream pressure gradient upstream of the island results in steering of flow around the island into the unobstructed thread. This diversion of water decreases the discharge through the constriction. Therefore, flow velocities within the constriction are not necessarily expected to be higher than those in the unobstructed thread, contrary to initial reports suggesting that higher velocities within the constriction are the main cause of erosion. We set up streamtable experiments with lapse rate imaging to illustrate the backwater effects of the channel constriction and the associated cross-stream steering of flow around a model island. Our experiments are scaled by channel roughness and slope rather than geometrically, as the main focus is to understand the mechanical behavior of flow in this type of island-landslide system. In addition, we studied the stream velocities and flow steering as well as the magnitude of the backwater effect in both the constricted and unobstructed channels using tracer particles in the time-lapse images. These experimental data are compared with calculated upstream backwater distances determined from the known water-surface slope, flow depth, total discharge, and bed roughness

  19. Effect of source and level of protein supplementation on rice straw utilization by Brahman steers.

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    McCann, J C; Sawyer, J E; Wickersham, T A

    2017-01-01

    Seven ruminally cannulated Brahman steers were used in a 7 × 4 incomplete block design to determine the effects of cottonseed meal (CSM; 43.9% CP, 82.9% RDP) or dried distillers' grains (DDG; 27.5% CP, 43.6% RDP) supplementation on rice straw utilization (47 g/kg CP and 681 g/kg NDF). Treatments consisted of a negative control receiving no supplement (control) and 3 levels (60, 120, and 180 mg N/kg BW) of either CSM or DDG. Periods were 14 d with 8 d for adaptation and 6 d for data collection. Steers had ad libitum access to rice straw and were fed supplements daily. Increased supplementation resulted in a linear increase ( ≤ 0.06) in forage OM intake from 13.5 g/kg BW by controls to 15.5 and 16.1 g/kg BW for 180 mg N/kg BW of DDG and CSM, respectively. No differences between sources were observed ( = 0.84). Total digestible OM intake was increased by supplementation (linear, supplement (g DM/d) to achieve isonitrogenous treatment levels. Total tract OM digestion tended to increase with DDG supplementation (linear, = 0.08) but not CSM supplementation ( = 0.19). Both supplements did not affect NDF digestion ( > 0.40) or calculated forage NDF digestibility ( > 0.40). Ruminal ammonia concentrations peaked 4 h after supplementation/feeding with the greatest concentration (4.0 m) observed for 180 mg N/kg BW of CSM and the lowest concentration at 4 h observed in the control (0.8 m). Provision of CSM resulted in a linear increase ( supplementation. Total VFA production linearly increased for both CSM and DDG supplementation ( = 0.09 and = 0.01, respectively). Protein supplements containing high and low levels of RDP were effective at improving intake and utilization of rice straw by Brahman steers.

  20. Hyperacute directional hearing and phonotactic steering in the cricket (Gryllus bimaculatus deGeer.

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    Stefan Schöneich

    2010-12-01

    Full Text Available Auditory mate or prey localisation is central to the lifestyle of many animals and requires precise directional hearing. However, when the incident angle of sound approaches 0° azimuth, interaural time and intensity differences gradually vanish. This poses a demanding challenge to animals especially when interaural distances are small. To cope with these limitations imposed by the laws of acoustics, crickets employ a frequency tuned peripheral hearing system. Although this enhances auditory directionality the actual precision of directional hearing and phonotactic steering has never been studied in the behaviourally important frontal range.Here we analysed the directionality of phonotaxis in female crickets (Gryllus bimaculatus walking on an open-loop trackball system by measuring their steering accuracy towards male calling song presented at frontal angles of incidence. Within the range of ±30°, females reliably discriminated the side of acoustic stimulation, even when the sound source deviated by only 1° from the animal's length axis. Moreover, for angles of sound incidence between 1° and 6° the females precisely walked towards the sound source. Measuring the tympanic membrane oscillations of the front leg ears with a laser vibrometer revealed between 0° and 30° a linear increasing function of interaural amplitude differences with a slope of 0.4 dB/°. Auditory nerve recordings closely reflected these bilateral differences in afferent response latency and intensity that provide the physiological basis for precise auditory steering.Our experiments demonstrate that an insect hearing system based on a frequency-tuned pressure difference receiver achieves directional hyperacuity which easily rivals best directional hearing in mammals and birds. Moreover, this directional accuracy of the cricket's hearing system is reflected in the animal's phonotactic motor response.