Comparison of biomechanical function at ideal and varied surgical placement for two lumbar artificial disc implant designs: mobile-core versus fixed-core.

PubMed

Moumene, Missoum; Geisler, Fred H

2007-08-01

Finite element model. To estimate the effect of lumbar mobile-core and fixed-core artificial disc design and placement on the loading of the facet joints, and stresses on the polyethylene core. Although both mobile-core and fixed-core lumbar artificial disc designs have been used clinically, the effect of their design and the effect of placement within the disc space on the structural element loading, and in particular the facets and the implant itself, have not been investigated. A 3D nonlinear finite element model of an intact ligamentous L4-L5 motion segment was developed and validated in all 6 df based on previous experiments conducted on human cadavers. Facet loading of a mobile-core TDR and a fixed-core TDR were estimated with 4 different prosthesis placements for 3 different ranges of motion. Placing the mobile-core TDR anywhere within the disc space reduced facet loading by more than 50%, while the fixed-core TDR increased facet loading by more than 10% when compared with the intact disc in axial rotation. For central (ideal) placement, the mobile- and fixed-core implants were subjected to compressive stresses on the order of 3 MPa and 24 MPa, respectively. The mobile-core stresses were not affected by implant placement, while the fixed-core stresses increased by up to 40%. A mobile-core artificial disc design is less sensitive to placement, and unloads the facet joints, compared with a fixed-core design. The decreased core stress may result in a reduced potential for wear in a mobile-core prosthesis compared with a fixed-core prosthesis, which may increase the functional longevity of the device.

Enhancing the Quality of E-Learning through Mobile Technology: A Socio-Cultural and Technology Perspective towards Quality E-Learning Applications

ERIC Educational Resources Information Center

Male, Galamoyo; Pattinson, Colin

2011-01-01

Purpose: This paper aims to present part of the work of an ongoing research project that is looking at socio- cultural and technological developments from a mobile technology convergence view; in order to show how culturally aware convergence developments in mobile technology can be adopted and employed for the betterment of society.…

[Implant with a mobile or a fixed bearing in unicompartmental knee joint replacemen].

PubMed

Matziolis, G; Tohtz, S; Gengenbach, B; Perka, C

2007-12-01

Although the goal of anatomical and functional joint reconstruction in unicompartmental knee replacement is well defined, no uniform implant design has become established. In particular, the differential indications for implantation of an implant with a mobile or a fixed bearing are still not clear. The long-term results of mobile and with fixed bearings are comparable, but there are significant differences in resulting knee joint kinematics, tribological properties and implant-associated complications. In unicompartmental knee replacement mobile bearings restore the physiological joint kinematics better than fixed implants, although the differences to total knee arthroplasty seem minor. The decoupling of mobile bearings from the tibia implant allows a high level of congruence with the femoral implant, resulting in larger contact areas than with fixed bearings. This fact in combination with the more physiological joint kinematics leads to less wear and a lower incidence of osteolyses with mobile bearings. Disadvantages of mobile bearings are the higher complication and early revision rates resulting from bearing dislocation and impingement syndromes caused by suboptimal implantation technique or instability. Especially in cases with ligamentous pathology fixed bearings involve a lower complication rate. It seems their use can also be beneficial in patients with a low level of activity, as problems related to wear are of minor importance for this subgroup. The data currently available allow differentiations between various indications for implants with mobile or fixed bearings, so that the implants can be matched to the patient and the joint pathology in unicompartmental knee joint replacement.

Higher forgotten joint score for fixed-bearing than for mobile-bearing total knee arthroplasty.

PubMed

Thienpont, E; Zorman, D

2016-08-01

To compare the postoperative subjective outcome for fixed- and mobile-bearing total knee arthroplasty (TKA) by using the forgotten joint score (FJS-12), a new patient-reported outcome score of 12 questions evaluating the potential of a patient to forget about his operated joint. The hypothesis of this study was that a mobile-bearing TKA would have a higher level of forgotten joint than a fixed-bearing model of the same design. A retrospective cohort study was conducted in 100 patients who underwent TKA at least 1 year [mean (SD) 18 (5) months] before with either a fixed-bearing (N = 50) or a mobile-bearing (N = 50) TKA from the same implant family. Clinical outcome was evaluated with the knee society score and patient-reported outcome with the forgotten joint score. No difference was observed for demographics in between both study groups. The mean (SD) postoperative FJS-12 for the fixed-bearing TKA was 71 (28) compared to a mean (SD) of 56.5 (30) for the mobile-bearing TKA. The clinical relevance of the present retrospective study is that it shows for the first time a significant difference between fixed- and mobile-bearing TKA by using a new patient-reported outcome score. The hypothesis that mobile-bearing TKA would have a higher degree of forgotten joint than a fixed-bearing TKA could not be confirmed. A level I prospective study should be set up to objectivise these findings. IV.

Superior long-term survival for fixed bearing compared with mobile bearing in ligament-balanced total knee arthroplasty.

PubMed

Heesterbeek, P J C; van Houten, A H; Klenk, J S; Eijer, H; Christen, B; Wymenga, A B; Schuster, A J

2018-05-01

Only few long-term data on ligament-balanced cruciate-retaining total knee arthroplasty (CR TKA) are currently available. Either a mobile- or fixed-bearing insert can be chosen, which showed good mid-term outcome and few complications and revisions. This multi-centre retrospective cross-sectional cohort study investigated the 12-year results of primary TKA using a balancing gap technique and compared survival and clinical outcome between fixed and mobile inserts. In this retrospective cross-sectional cohort study, 557 cases of three clinics (2 Swiss, 1 Dutch) operated between 1998 and 2003 with the first series of a TKA implanted with a balanced gap technique (433 (77.7%) fixed, 124 (22.3%) mobile (anterior-posterior gliding (7-9 mm) and rotational (15°) degrees of freedom) inserts) were included for survival analysis (Kaplan-Meier, by insert type). At the 12-year follow-up (FU) examination of 189 cases, range of motion, knee society score (KSS), numeric rating scale (NRS) for pain and satisfaction were determined and radiographs were evaluated by median tests, by insert type. Of 521 cases available for analysis, 28 (5.4%; 11 fixed, 17 mobile bearing) were revised. Mean cumulative survival after 12.4 years was 97.0% (95% CI 94.7-98.4) for fixed bearings and 85.4% (95% CI 77.5-90.7) after 12.2 years for mobile bearings, p < 0.0001. Patients' mean age at 11.0 years FU (n = 189) was 78.0 (range 54.5-97.3) years. Mean total KSS was 157.8 (24-200) points, and mean passive flexion was 114° (45-150); no clinical score differed significantly between fixed and mobile bearings. This study showed a superior survival for fixed bearing compared with mobile bearing in a CR TKA using a ligament-balanced technique after more than 12 years. Clinical outcomes are excellent to good after long-term follow-up, and similar for fixed and mobile bearing. Therapeutic studies-retrospective cohort study, Level III.

Outcome of Unicompartmental Knee Arthroplasty: A Systematic Review of Comparative Studies between Fixed and Mobile Bearings Focusing on Complications

PubMed Central

Ko, Young-Bong; Gujarathi, Manan Ramesh

2015-01-01

The purpose of this systematic review is to collate results of studies comparing fixed and mobile bearing unicompartmental knee arthroplasty (UKA), focusing on complications and timing for reoperations. Out of 723 results derived from PubMed, EMBASE and Cochrane database search engines on bearings in arthroplasty, 10 studies comparing clinical results of fixed bearings to mobile bearings in UKA were found eligible for analysis. The reoperation rate was calculated using a novel method such as reoperations per hundred component years, and the causes of specific reoperations were investigated. The overall reoperation rate per hundred component years was similar between the mobile bearings (1.392) and fixed bearings (1.377); however, mobile bearings were more susceptible to reoperations in cases with aseptic loosening (0.393>0.255), progression of arthritis (0.428>0.357) and implant dislocation (0.286>0). The overall incidence of complications is similar for fixed and mobile bearing designs in UKA. The discussion on complications presented above may assist surgeons in their choice of bearing design. PMID:26389066

Objective Speech Quality Assessment Based on Payload Discrimination of Lost Packets for Cellular Phones in NGN Environment

NASA Astrophysics Data System (ADS)

Uemura, Satoshi; Fukumoto, Norihiro; Yamada, Hideaki; Nakamura, Hajime

A feature of services provided in a Next Generation Network (NGN) is that the end-to-end quality is guaranteed. This is quite a challenging issue, given the considerable fluctuation in network conditions within a Fixed Mobile Convergence (FMC) network. Therefore, a novel approach, whereby a network node and a mobile terminal such as a cellular phone cooperate with each other to control service quality is essential. In order to achieve such cooperation, the mobile terminal needs to become more intelligent so it can estimate the service quality, including the user's perceptual quality, and notify the measurement result to the network node. Subsequently, the network node implements some kind of service control function, such as a resource and admission control function, based on the notification from the mobile terminal. In this paper, the role of the mobile terminal in such collaborative system is focused on. As a part of a QoS/QoE measurement system, we describe an objective speech quality assessment with payload discrimination of lost packets to measure the user's perceptual quality of VoIP. The proposed assessment is so simple that it can be implemented on a cellular phone. We therefore did this as part of the QoS/QoE measurement system. By using the implemented system, we can measure the user's perceptual quality of VoIP as well as the network QoS metrics, in terms of criteria such as packet loss rate, jitter and burstiness in real time.

A robot control architecture supported on contraction theory

NASA Astrophysics Data System (ADS)

Silva, Jorge; Sequeira, João; Santos, Cristina

2017-01-01

This paper proposes fundamentals for stability and success of a global system composed by a mobile robot, a real environment and a navigation architecture with time constraints. Contraction theory is a typical framework that provides tools and properties to prove the stability and convergence of the global system to a unique fixed point that identifies the mission success. A stability indicator based on the combination contraction property is developed to identify the mission success as a stability measure. The architecture is fully designed through C1 nonlinear dynamical systems and feedthrough maps, which makes it amenable for contraction analysis. Experiments in a realistic and uncontrolled environment are realised to verify if inherent perturbations of the sensory information and of the environment affect the stability and success of the global system.

Comparison of Alignment Correction Angles Between Fixed-Bearing and Mobile-Bearing UKA.

PubMed

Inoue, Atsuo; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Yamazoe, Shoichi; Kubo, Toshikazu

2016-01-01

Good outcomes have been reported with both fixed-bearing and mobile-bearing unicompartmental knee arthroplasty (UKA). However, overcorrected alignment could induce the progression of arthritis on the non-arthroplasty side. Changes of limb alignment after UKA with both types of bearings (fixed bearing: 24 knees, mobile bearing: 28 knees) were investigated. The mean difference between the preoperative standing femoral-tibial angle (FTA) and postoperative standing FTA was significantly larger in mobile bearing UKA group. In fixed-bearing UKA, there must be some laxity in MCL tension so that a 2-mm tension gauge can be inserted. In mobile-bearing UKA, appropriate MCL tension is needed to prevent bearing dislocation. This difference in MCL tension may have caused the difference in the correction angle between the groups. Copyright © 2016 Elsevier Inc. All rights reserved.

The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion

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

Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin

Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less

The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion

DOE PAGES

Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin

2016-11-15

Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less

Simultaneous mobile- and fixed-bearing total knee replacement in the same patients. A prospective comparison of mid-term outcomes using a similar design of prosthesis.

PubMed

Kim, Y-H; Kim, D-Y; Kim, J-S

2007-07-01

We conducted a randomised prospective study to evaluate the clinical and radiological results of a mobile- and fixed-bearing total knee replacement of similar design in 174 patients who had bilateral simultaneous knee replacement. The mean follow-up was for 5.6 years (5.2 to 6.1). The total knee score, pain score, functional score and range of movement were not statistically different (p > 0.05) between the two groups. Osteolysis was not seen in any knee in either group. Two knees (1%) in the mobile-bearing group required revision because of infection; none in the fixed-bearing group needed revision. Excellent results can be achieved with both mobile- and fixed-bearing prostheses of similar design at mid-term follow-up. We could demonstrate no significant clinical advantage for a mobile bearing.

47 CFR 24.5 - Terms and definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... in the National Geodetic Survey (NGS) data base. (Source: National Geodetic Survey, U.S. Department... antenna site. Base Station. A land station in the land mobile service. Broadband PCS. PCS services.... Fixed Station. A station in the fixed service. Land Mobile Service. A mobile service between base...

47 CFR 24.5 - Terms and definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... in the National Geodetic Survey (NGS) data base. (Source: National Geodetic Survey, U.S. Department... antenna site. Base Station. A land station in the land mobile service. Broadband PCS. PCS services.... Fixed Station. A station in the fixed service. Land Mobile Service. A mobile service between base...

47 CFR 24.5 - Terms and definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... in the National Geodetic Survey (NGS) data base. (Source: National Geodetic Survey, U.S. Department... antenna site. Base Station. A land station in the land mobile service. Broadband PCS. PCS services.... Fixed Station. A station in the fixed service. Land Mobile Service. A mobile service between base...

47 CFR 24.5 - Terms and definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... in the National Geodetic Survey (NGS) data base. (Source: National Geodetic Survey, U.S. Department... antenna site. Base Station. A land station in the land mobile service. Broadband PCS. PCS services.... Fixed Station. A station in the fixed service. Land Mobile Service. A mobile service between base...

Diverging patterns with endogenous labor migration.

PubMed

Reichlin, P; Rustichini, A

1998-05-05

"The standard neoclassical model cannot explain persistent migration flows and lack of cross-country convergence when capital and labor are mobile. Here we present a model where both phenomena may take place.... Our model is based on the Arrow-Romer approach to endogenous growth theory. We single out the importance of a (however weak) scale effect from the size of the workforce.... The main conclusion of this simple model is that lack of convergence, or even divergence, among countries is possible, even with perfect capital mobility and labor mobility." excerpt

No difference between fixed- and mobile-bearing total knee arthroplasty in activities of daily living and pain: a randomized clinical trial.

PubMed

Amaro, Joicemar Tarouco; Arliani, Gustavo Gonçalves; Astur, Diego Costa; Debieux, Pedro; Kaleka, Camila Cohen; Cohen, Moises

2017-06-01

Until now, there are no definitive conclusions regarding functional differences related to middle- and long-term everyday activities and patient pain following implantation of mobile- and fixed-platform tibial prostheses. The aim of this study was to determine whether there are middle-term differences in knee function and pain in patients undergoing fixed- and mobile-bearing total knee arthroplasty (TKA). Eligible patients were randomized into two groups: the first group received TKA implantation with a fixed tibial platform (group A); the second group received TKA with a mobile tibial platform (group B). Patients were followed up (2 years), and their symptoms and limitations in daily living activities were evaluated using the Knee Outcome Survey-Activities of Daily Living Scale (ADLS), in addition to pain evaluation assessed using the pain visual analogue scale (VAS). There were no significant differences in function and symptoms in the ADLS and VAS between the study groups. The type of platform used in TKA (fixed vs. mobile) does not change the symptoms, function or pain of patients 2 years post-surgery. Although mobile TKAs may have better short-term results, at medium- and long-term follow-up they do not present important clinical differences compared with fixed-platform TKAs. This information is important so that surgeons can choose the most suitable implant for each patient. Randomized clinical trial, Level I.

Role of immediate recurrent laryngeal nerve reconstruction in surgery for thyroid cancers with fixed vocal cords.

PubMed

Iwaki, Shinobu; Maeda, Tatsuyoshi; Saito, Miki; Otsuki, Naoki; Takahashi, Miki; Wakui, Emi; Shinomiya, Hirotaka; Morimoto, Koichi; Inoue, Hiroyuki; Masuoka, Hiroo; Miyauchi, Akira; Nibu, Ken-Ichi

2017-03-01

Quality of voice after immediate recurrent laryngeal nerve (RLN) reconstruction in thyroid cancers has not been thoroughly studied. Thirteen patients with fixed vocal cords (fixed vocal cord group) and 8 patients with intact or impaired mobile vocal cords (mobile vocal cord group) who had immediate RLN reconstruction simultaneously with total thyroidectomy, and patients who had arytenoid adduction and thyroplasty for vocal cord paralysis caused by previous surgery (arytenoid adduction thyroplasty group) were enrolled in this study. Preoperative phonation efficiency index was significantly lower (p = .008) in the fixed vocal cord group than in the mobile vocal cord group. One year after surgery, all voice parameters of the patients in the fixed vocal cord group had improved, compared with their preoperative data. The fixed vocal cord group had attained satisfactory voice qualities equivalent to those of the mobile vocal cord group in terms of various voice parameters. The present results support the idea that immediate RLN reconstruction at the time of surgery for thyroid cancers may spare the need for subsequent arytenoid adduction thyroplasty even in the patients with preoperatively fixed vocal cords. © 2016 Wiley Periodicals, Inc. Head Neck 39: 427-431, 2017. © 2016 Wiley Periodicals, Inc.

Information transmission on hybrid networks

NASA Astrophysics Data System (ADS)

Chen, Rongbin; Cui, Wei; Pu, Cunlai; Li, Jie; Ji, Bo; Gakis, Konstantinos; Pardalos, Panos M.

2018-01-01

Many real-world communication networks often have hybrid nature with both fixed nodes and moving modes, such as the mobile phone networks mainly composed of fixed base stations and mobile phones. In this paper, we discuss the information transmission process on the hybrid networks with both fixed and mobile nodes. The fixed nodes (base stations) are connected as a spatial lattice on the plane forming the information-carrying backbone, while the mobile nodes (users), which are the sources and destinations of information packets, connect to their current nearest fixed nodes respectively to deliver and receive information packets. We observe the phase transition of traffic load in the hybrid network when the packet generation rate goes from below and then above a critical value, which measures the network capacity of packets delivery. We obtain the optimal speed of moving nodes leading to the maximum network capacity. We further improve the network capacity by rewiring the fixed nodes and by considering the current load of fixed nodes during packets transmission. Our purpose is to optimize the network capacity of hybrid networks from the perspective of network science, and provide some insights for the construction of future communication infrastructures.

Comparison of in vivo polyethylene wear particles between mobile- and fixed-bearing TKA in the same patients.

PubMed

Minoda, Yukihide; Hata, Kanako; Ikebuchi, Mitsuhiko; Mizokawa, Shigekazu; Ohta, Yoichi; Nakamura, Hiroaki

2017-09-01

Polyethylene wear particle generation is one of the most important factors that affects the mid- to long-term results of total knee arthroplasties (TKA). Mobile-bearing total knee prostheses were developed to reduce polyethylene wear generation. However, whether mobile-bearing prostheses actually generate fewer polyethylene wear particles than fixed-bearing prostheses remains controversial. The aim of this study was to compare, within individual patients, the in vivo polyethylene wear particles created by a newly introduced mobile-bearing prosthesis in one knee and a conventional fixed-bearing prosthesis in other knee. Eighteen patients receiving bilateral TKAs to treat osteoarthritis were included. The synovial fluid was obtained from 36 knees at an average of 3.5 years after the operation. The in vivo polyethylene wear particles were isolated from the synovial fluid using a previously validated method and examined using a scanning electron microscope and an image analyser. The size and shape of the polyethylene wear particles from the mobile-bearing prostheses were similar to those from the conventional fixed-bearing prostheses. Although the number of wear particles from the mobile-bearing prosthesis (1.63 × 10 7  counts/knee) appeared smaller than that from the fixed-bearing prosthesis (2.16 × 10 7  counts/knee), the difference was not statistically significant. The current in vivo study shows that no statistically significant differences were found between the polyethylene wear particles generated by a newly introduced mobile-bearing PS prosthesis and a conventional fixed-bearing PS prosthesis during the early clinical stage after implantation. Therapeutic study, Level III.

A dual method for optimal control problems with initial and final boundary constraints.

NASA Technical Reports Server (NTRS)

Pironneau, O.; Polak, E.

1973-01-01

This paper presents two new algorithms belonging to the family of dual methods of centers. The first can be used for solving fixed time optimal control problems with inequality constraints on the initial and terminal states. The second one can be used for solving fixed time optimal control problems with inequality constraints on the initial and terminal states and with affine instantaneous inequality constraints on the control. Convergence is established for both algorithms. Qualitative reasoning indicates that the rate of convergence is linear.

Comparison of fixed-bearing and mobile-bearing total knee arthroplasty after high tibial osteotomy.

PubMed

Hernigou, Philippe; Huys, Maxime; Pariat, Jacques; Roubineau, François; Flouzat Lachaniette, Charles Henri; Dubory, Arnaud

2018-02-01

There is no information comparing the results of fixed-bearing total knee replacement and mobile-bearing total knee replacement in the same patients previously treated by high tibial osteotomy. The purpose was therefore to compare fixed-bearing and mobile-bearing total knee replacements in patients treated with previous high tibial osteotomy. We compared the results of 57 patients with osteoarthritis who had received a fixed-bearing prosthesis after high tibial osteotomy with the results of 41 matched patients who had received a rotating platform after high tibial osteotomy. The match was made for length of follow-up period. The mean follow-up was 17 years (range, 15-20 years). The patients were assessed clinically and radiographically. The pre-operative knee scores had no statistically significant differences between the two groups. So was the case with the intra-operative releases, blood loss, thromboembolic complications and infection rates in either group. There was significant improvement in both groups of knees, and no significant difference was observed between the groups (i.e., fixed-bearing and mobile-bearing knees) for the mean Knee Society knee clinical score (95 and 92 points, respectively), or the Knee Society knee functional score (82 and 83 points, respectively) at the latest follow-up. However, the mean post-operative knee motion was higher for the fixed-bearing group (117° versus 110°). In the fixed-bearing group, one knee was revised because of periprosthetic fracture. In the rotating platform mobile-bearing group, one knee was revised because of aseptic loosening of the tibial component. The Kaplan-Meier survivorship for revision at ten years of follow-up was 95.2% for the fixed bearing prosthesis and 91.1% for the rotating platform mobile-bearing prosthesis. Although we did manage to detect significant differences mainly in clinical and radiographic results between the two groups, we found no superiority or inferiority of the mobile-bearing total knee prosthesis over the fixed-bearing total knee prosthesis for patients previously operated by high tibial osteotomy.

Rigid and non-rigid micro-plates: Philippines and Myanmar-Andaman case studies

NASA Astrophysics Data System (ADS)

Rangin, Claude

2016-01-01

Generally, tectonic plates are considered as rigid. Oblique plate convergence favors the development of micro-plates along the converging boundaries. The north-south-trending Philippines archipelago (here named Philippine Mobile Belt, PMB), a few hundreds kilometers wide, is one of such complex tectonic zones. We show here that it is composed of rigid rotating crustal blocks (here called platelets). In Myanmar, the northernmost tip of the Sumatra-Andaman subduction system is another complex zone made of various crustal blocks in-between convergent plates. Yet, contrary to PMB, it sustains internal deformation with platelet buckling, altogether indicative of a non-rigid behavior. Therefore, the two case studies, Philippine Mobile Belt and Myanmar-Andaman micro-plate (MAS), illustrate the complexity of micro-plate tectonics and kinematics at convergent plate boundaries.

Different femorotibial contact points between fixed- and mobile-bearing TKAs do not show clinical impact.

PubMed

van Stralen, R A; Heesterbeek, P J C; Wymenga, A B

2015-11-01

In anteroposterior (AP)-gliding mobile-bearing total knee arthroplasty (TKA), the femoral component can theoretically slide forward resulting in a more anterior contact point, causing pain due to impingement. A lower lever arm of the extensor apparatus can also attribute to higher patella pressures and pain. The goal of this study was to determine the contact point in a cohort of mobile- and fixed-bearing TKAs, to determine whether the contact point lies more anteriorly in mobile-bearing TKA and to confirm whether this results in anterior knee pain. We used 38 fixed-bearing TKA and 40 mobile-bearing TKA from a randomized trial with straight lateral knee X-rays and measured the contact point. The functional outcome was measured by Knee Society Score at 12 months postoperatively. Pain scores were analysed using a VAS score (0-100 mm) in all patients at rest and when moving. Difficulty at rising up out of a chair was also assessed using a VAS score. The contact point in mobile-bearing TKA was situated at 59.5 % of the AP distance of the tibia and in the fixed-bearing TKA group at 66.1 % (P< 0.05). Patients with mobile- and fixed-bearing TKAs had similar knee scores, pain scores and difficulty in chair rise. No significant correlation was found between contact point and knee pain. The hypothesis of a more anterior contact point in the mobile-bearing cohort was confirmed but no correlation with functional and pain scores in this cohort could be found. The tibiofemoral contact point could not be correlated with a different clinical outcome and higher incidence of anterior knee pain. This study further adds to the knowledge on possible differences between mobile- and fixed-bearing prostheses. Next to that, bad outcomes could not be explained by CP. Case series, Level IV.

The Incidence and Short Term Functional Effect of Partial PCL Release in Fixed and Mobile Bearing PCL Retaining TKA.

PubMed

Schwarzkopf, Ran; Woolwine, Spencer; Josephs, Lee; Scott, Richard D

2015-12-01

Posterior cruciate ligament (PCL) release may be required to balance the flexion gap in PCL retaining TKA. This study examines the incidence and functional consequences of PCL release in both fixed and mobile bearing TKA. A consecutive series of 1388 TKAs with 1014 fixed bearing, and 374 mobile bearing implants were reviewed for prevalence of partial PCL release, restoration of potential flexion and objective knee stability at minimum one-year follow-up. Patients receiving mobile bearing inserts were more likely to need partial PCL release (42% versus 17.5%). The occurrence of partial PCL release did not have a significant impact on knee range of motion and subjective knee stability. The need for a partial PCL release appears to be greater in mobile than in fixed bearing. Knees that required a release in both groups demonstrated no difference in restoration of flexion compared with unreleased knees and no adverse effects on flexion stability. Copyright © 2015 Elsevier Inc. All rights reserved.

Permitted and forbidden sets in symmetric threshold-linear networks.

PubMed

Hahnloser, Richard H R; Seung, H Sebastian; Slotine, Jean-Jacques

2003-03-01

The richness and complexity of recurrent cortical circuits is an inexhaustible source of inspiration for thinking about high-level biological computation. In past theoretical studies, constraints on the synaptic connection patterns of threshold-linear networks were found that guaranteed bounded network dynamics, convergence to attractive fixed points, and multistability, all fundamental aspects of cortical information processing. However, these conditions were only sufficient, and it remained unclear which were the minimal (necessary) conditions for convergence and multistability. We show that symmetric threshold-linear networks converge to a set of attractive fixed points if and only if the network matrix is copositive. Furthermore, the set of attractive fixed points is nonconnected (the network is multiattractive) if and only if the network matrix is not positive semidefinite. There are permitted sets of neurons that can be coactive at a stable steady state and forbidden sets that cannot. Permitted sets are clustered in the sense that subsets of permitted sets are permitted and supersets of forbidden sets are forbidden. By viewing permitted sets as memories stored in the synaptic connections, we provide a formulation of long-term memory that is more general than the traditional perspective of fixed-point attractor networks. There is a close correspondence between threshold-linear networks and networks defined by the generalized Lotka-Volterra equations.

Learning in the Machine: Random Backpropagation and the Deep Learning Channel.

PubMed

Baldi, Pierre; Sadowski, Peter; Lu, Zhiqin

2018-07-01

Random backpropagation (RBP) is a variant of the backpropagation algorithm for training neural networks, where the transpose of the forward matrices are replaced by fixed random matrices in the calculation of the weight updates. It is remarkable both because of its effectiveness, in spite of using random matrices to communicate error information, and because it completely removes the taxing requirement of maintaining symmetric weights in a physical neural system. To better understand random backpropagation, we first connect it to the notions of local learning and learning channels. Through this connection, we derive several alternatives to RBP, including skipped RBP (SRPB), adaptive RBP (ARBP), sparse RBP, and their combinations (e.g. ASRBP) and analyze their computational complexity. We then study their behavior through simulations using the MNIST and CIFAR-10 bechnmark datasets. These simulations show that most of these variants work robustly, almost as well as backpropagation, and that multiplication by the derivatives of the activation functions is important. As a follow-up, we study also the low-end of the number of bits required to communicate error information over the learning channel. We then provide partial intuitive explanations for some of the remarkable properties of RBP and its variations. Finally, we prove several mathematical results, including the convergence to fixed points of linear chains of arbitrary length, the convergence to fixed points of linear autoencoders with decorrelated data, the long-term existence of solutions for linear systems with a single hidden layer and convergence in special cases, and the convergence to fixed points of non-linear chains, when the derivative of the activation functions is included.

Lateral unicompartmental knee replacement: fixed or mobile bearing?

PubMed

Forster, M C; Bauze, A J; Keene, G C R

2007-09-01

Between May 2001 and May 2003, 233 consecutive Preservation unicompartmental knee replacements (UKR) were performed. Of these, 30 were lateral UKRs (13%) performed in 12 men and 16 women (2 bilateral cases) with a mean age of 67 years (range 36-93 years). A metal-backed mobile bearing tibial component was used in 13 knees and an all-polyethylene fixed bearing tibial component in 17 knees. The patients were reviewed prospectively at 1 and 2 years. The 2 year results show no difference in range of motion or function between the mobile and fixed bearing versions of the Preservation knee when used on the lateral side. There were three early revisions, all in the mobile bearing group.

Land mobile satellite system requirements

NASA Astrophysics Data System (ADS)

Kiesling, J. D.

1983-05-01

A Land Mobile Satellite System (LMSS) provides voice, data and related communications services to moving vehicles and persons. Communications between the mobiles and satellite are in the 806-890 MHz band. The satellite translates these signals to a ""fixed services band'' such as 14/12 GHz band (Ku-band), and communicates in this band with fixed terminals called gateways. The gateways are located at convenient places such as telephone switches (which provide entry into the national telephone system), dispatcher headquarters, computer centers, etc. Communications are therefore principally mobile to fixed. A third communications link, also at Ku-band, is needed between the satellite and a single fixed ground station. This link provides satellite command, telemetry and ranging and also provides a network control function. The latter, through a common signalling system, receives requests and assigns channel slots, and otherwise controls, monitors and polices the network and collects billing information.

Land mobile satellite system requirements

NASA Technical Reports Server (NTRS)

Kiesling, J. D.

1983-01-01

A Land Mobile Satellite System (LMSS) provides voice, data and related communications services to moving vehicles and persons. Communications between the mobiles and satellite are in the 806-890 MHz band. The satellite translates these signals to a ""fixed services band'' such as 14/12 GHz band (Ku-band), and communicates in this band with fixed terminals called gateways. The gateways are located at convenient places such as telephone switches (which provide entry into the national telephone system), dispatcher headquarters, computer centers, etc. Communications are therefore principally mobile to fixed. A third communications link, also at Ku-band, is needed between the satellite and a single fixed ground station. This link provides satellite command, telemetry and ranging and also provides a network control function. The latter, through a common signalling system, receives requests and assigns channel slots, and otherwise controls, monitors and polices the network and collects billing information.

Robust fixed-time synchronization of delayed Cohen-Grossberg neural networks.

PubMed

Wan, Ying; Cao, Jinde; Wen, Guanghui; Yu, Wenwu

2016-01-01

The fixed-time master-slave synchronization of Cohen-Grossberg neural networks with parameter uncertainties and time-varying delays is investigated. Compared with finite-time synchronization where the convergence time relies on the initial synchronization errors, the settling time of fixed-time synchronization can be adjusted to desired values regardless of initial conditions. Novel synchronization control strategy for the slave neural network is proposed. By utilizing the Filippov discontinuous theory and Lyapunov stability theory, some sufficient schemes are provided for selecting the control parameters to ensure synchronization with required convergence time and in the presence of parameter uncertainties. Corresponding criteria for tuning control inputs are also derived for the finite-time synchronization. Finally, two numerical examples are given to illustrate the validity of the theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

Migration and clinical outcome of mobile-bearing versus fixed-bearing single-radius total knee arthroplasty.

PubMed

Van Hamersveld, Koen T; Marang-Van De Mheen, Perla J; Van Der Heide, Huub J L; Van Der Linden-Van Der Zwaag, Henrica M J; Valstar, Edward R; Nelissen, Rob G H H

2018-04-01

Background and purpose - Mobile-bearing total knee prostheses (TKPs) were developed in the 1970s in an attempt to increase function and improve implant longevity. However, modern fixed-bearing designs like the single-radius TKP may provide similar advantages. We compared tibial component migration measured with radiostereometric analysis (RSA) and clinical outcome of otherwise similarly designed cemented fixed-bearing and mobile-bearing single-radius TKPs. Patients and methods - RSA measurements and clinical scores were assessed in 46 randomized patients at baseline, 6 months, 1 year, and annually thereafter up to 6 years postoperatively. A linear mixed-effects model was used to analyze the repeated measurements. Results - Both groups showed comparable migration (p = 0.3), with a mean migration at 6-year follow-up of 0.90 mm (95% CI 0.49-1.41) for the fixed-bearing group compared with 1.22 mm (95% CI 0.75-1.80) for the mobile-bearing group. Clinical outcomes were similar between groups. 1 fixed-bearing knee was revised for aseptic loosening after 6 years and 2 knees (1 in each group) were revised for late infection. 2 knees (1 in each group) were suspected for loosening due to excessive migration. Another mobile-bearing knee was revised after an insert dislocation due to failure of the locking mechanism 6 weeks postoperatively, after which study inclusion was preliminary terminated. Interpretation - Fixed-bearing and mobile-bearing single-radius TKPs showed similar migration. The latter may, however, expose patients to more complex surgical techniques and risks such as insert dislocations inherent to this rotating-platform design.

Fixed and mobile-bearing total ankle prostheses: Effect on tibial bone strain.

PubMed

Terrier, Alexandre; Fernandes, Caroline Sieger; Guillemin, Maïka; Crevoisier, Xavier

2017-10-01

Total ankle replacement is associated to a high revision rate. To improve implant survival, the potential advantage of prostheses with fixed bearing compared to mobile bearing is unclear. The objective of this study was to test the hypothesis that fixed and mobile bearing prostheses are associated with different biomechanical quantities typically associated to implant failure. With a validated finite element model, we compared three cases: a prosthesis with a fixed bearing, a prosthesis with a mobile bearing in a centered position, and a prosthesis with mobile bearing in an eccentric position. Both prostheses were obtained from the same manufacturer. They were tested on seven tibias with maximum axial compression force during walking. We tested the hypothesis that there was a difference of bone strain, bone-implant interfacial stress, and bone support between the three cases. We also evaluated, for the three cases, the correlations between bone support, bone strain and bone-implant interfacial stress. There were no statistically significant differences between the three cases. Overall, bone support was mainly trabecular, and less effective in the posterior side. Bone strain and bone-implant interfacial stress were strongly correlated to bone support. Even if slight differences are observed between fixed and mobile bearing, it is not enough to put forward the superiority of one of these implants regarding their reaction to axial compression. When associated to the published clinical results, our study provides no argument to warn surgeons against the use of two-components fixed bearing implants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mobile vs. fixed bearing unicondylar knee arthroplasty: A randomized study on short term clinical outcomes and knee kinematics.

PubMed

Li, Ming G; Yao, Felix; Joss, Brendan; Ioppolo, James; Nivbrant, Bo; Wood, David

2006-10-01

The literature contains limited yet controversial information regarding whether a fixed or a mobile bearing implant should be used in unicompartmental knee arthroplasty (UKA). This randomized study was to further document the performance and comparison of the two designs. Fifty-six knees in 48 patients (mean age of 72 years) undergoing medial UKA were randomized into a fixed bearing (Miller/Galante) or a mobile bearing (Oxford) UKA. The 2 year clinical outcomes (clinical scores), radiographic findings, and weight bearing knee kinematics (assessed using RSA) were compared between the two groups. The mobile bearing knees displayed a larger and an incrementally increased tibial internal rotation (4.3 degrees, 7.6 degrees, 9.5 degrees vs. 3.0 degrees, 3.0 degrees, 4.2 degrees respectively at 30 degrees, 60 degrees, 90 degrees of knee flexion) compared to the fixed ones. The medial femoral condyle in the mobile bearing knees remained 2 mm from the initial position vs. a 4.2 mm anterior translation in the fixed bearing knees during knee flexion. The contact point in the mobile bearing implant moved 2 mm posteriorly vs. a 6 mm anterior movement in the other group. The mobile bearing knees had a lower incidence of radiolucency at the bone implant interface (8% vs. 37%, p < 0.05). The incidence of lateral compartment OA and progression of OA at patello-femoral joint were equal. No differences were found regarding Knee Society Scores, WOMAC, and SF-36 scores (p > 0.05). This study indicates that mobile bearing knees had a better kinematics, a lower incidence of radiolucency but not yet a better knee function at 2 years.

Mobile Versus Fixed Facility: Latinas' Attitudes and Preferences for Obtaining a Mammogram.

PubMed

Scheel, John R; Tillack, Allison A; Mercer, Lauren; Coronado, Gloria D; Beresford, Shirley A A; Molina, Yamile; Thompson, Beti

2018-01-01

Mobile mammographic services have been proposed as a way to reduce Latinas' disproportionate late-stage presentation compared with white women by increasing their access to mammography. The aims of this study were to assess why Latinas may not use mobile mammographic services and to explore their preferences after using these services. Using a mixed-methods approach, a secondary analysis was conducted of baseline survey data (n = 538) from a randomized controlled trial to improve screening mammography rates among Latinas in Washington. Descriptive statistics and bivariate regression were used to characterize mammography location preferences and to test for associations with sociodemographic indices, health care access, and perceived breast cancer risk and beliefs. On the basis of these findings, a qualitative study (n = 18) was used to explore changes in perceptions after using mobile mammographic services. More Latinas preferred obtaining a mammogram at a fixed facility (52.3% [n = 276]) compared with having no preference (46.3% [n = 249]) and preferring mobile mammographic services (1.7% [n = 9]). Concerns about privacy and comfort (15.6% [n = 84]) and about general quality (10.6% [n = 57]) were common reasons for preferring a fixed facility. Those with no history of mammography preferred a fixed facility (P < .05). In the qualitative study, Latinas expressed similar initial concerns but became positive toward the mobile mammographic services after obtaining a mammogram. Although most Latinas preferred obtaining a mammogram at a fixed facility, positive experiences with mobile mammography services changed their attitudes toward them. These findings highlight the need to include community education when using mobile mammographic service to increase screening mammography rates in underserved communities. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

International comparative evaluation of knee replacement with fixed or mobile-bearing posterior-stabilized prostheses.

PubMed

Graves, Stephen; Sedrakyan, Art; Baste, Valborg; Gioe, Terence J; Namba, Robert; Martínez Cruz, Olga; Stea, Susanna; Paxton, Elizabeth; Banerjee, Samprit; Isaacs, Abby J; Robertsson, Otto

2014-12-17

Posterior-stabilized total knee prostheses were introduced to address instability secondary to loss of posterior cruciate ligament function, and they have either fixed or mobile bearings. Mobile bearings were developed to improve the function and longevity of total knee prostheses. In this study, the International Consortium of Orthopaedic Registries used a distributed health data network to study a large cohort of posterior-stabilized prostheses to determine if the outcome of a posterior-stabilized total knee prosthesis differs depending on whether it has a fixed or mobile-bearing design. Aggregated registry data were collected with a distributed health data network that was developed by the International Consortium of Orthopaedic Registries to reduce barriers to participation (e.g., security, proprietary, legal, and privacy issues) that have the potential to occur with the alternate centralized data warehouse approach. A distributed health data network is a decentralized model that allows secure storage and analysis of data from different registries. Each registry provided data on mobile and fixed-bearing posterior-stabilized prostheses implanted between 2001 and 2010. Only prostheses associated with primary total knee arthroplasties performed for the treatment of osteoarthritis were included. Prostheses with all types of fixation were included except for those with the rarely used reverse hybrid (cementless tibial and cemented femoral components) fixation. The use of patellar resurfacing was reported. The outcome of interest was time to first revision (for any reason). Multivariate meta-analysis was performed with linear mixed models with survival probability as the unit of analysis. This study includes 137,616 posterior-stabilized knee prostheses; 62% were in female patients, and 17.6% had a mobile bearing. The results of the fixed-effects model indicate that in the first year the mobile-bearing posterior-stabilized prostheses had a significantly higher hazard ratio (1.86) than did the fixed-bearing posterior-stabilized prostheses (95% confidence interval, 1.28 to 2.7; p = 0.001). For all other time intervals, the mobile-bearing posterior-stabilized prostheses had higher hazard ratios; however, these differences were not significant. Mobile-bearing posterior-stabilized prostheses had an increased rate of revision compared with fixed-bearing posterior-stabilized prostheses. This difference was evident in the first year. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Effect of Mobile Phone Usage on Nickel Ions Release and pH of Saliva in Patients Undergoing Fixed Orthodontic Treatment.

PubMed

Nanjannawar, Lalita Girish; Girme, Tejashree Suresh; Agrawal, Jiwanasha Manish; Agrawal, Manish Suresh; Fulari, Sangamesh Gurunath; Shetti, Shraddha Subhash; Kagi, Vishwal Ajith

2017-09-01

Hand held mobile phones are presently the most popular means of communication worldwide and have transformed our lives in many aspects. The widespread use of such devices have resulted in growing concerns regarding harmful effects of radiations emitted by them. This study was designed to evaluate the effects of mobile phone usage on nickel ion release as well as pH of saliva in patients with fixed orthodontic appliances. To assess the level of nickel ions in saliva and pH of saliva in mobile phone users undergoing fixed orthodontic treatment using inductively coupled plasma atomic emission spectrometry. A total of 42 healthy patients with fixed orthodontic appliance in mouth for a duration of six to nine months were selected for the study. They were divided into experimental group (n=21) consisting of mobile phone users and control group (n=21) of non mobile phone users. Saliva samples were collected from both the groups and nickel ion levels were measured using inductively coupled plasma-mass spectroscopy. The pH values were also assessed for both groups using pH meter. Unpaired t-test was used for the data analysis. Statistical analysis revealed that though the pH levels were reduced and the nickel ion levels were higher in the experimental group compared to the control group, the results were non significant. Mobile phone usage may affect the pH of saliva and result in increased release of nickel ions in saliva of patients with fixed orthodontic appliances in the oral cavity.

A sub-target approach to the kinodynamic motion control of a wheeled mobile robot

NASA Astrophysics Data System (ADS)

Motonaka, Kimiko; Watanabe, Keigo; Maeyama, Shoichi

2018-02-01

A mobile robot with two independently driven wheels is popular, but it is difficult to stabilize it by a continuous controller with a constant gain, due to its nonholonomic property. It is guaranteed that a nonholonomic controlled object can always be converged to an arbitrary point using a switching control method or a quasi-continuous control method based on an invariant manifold in a chained form. From this, the authors already proposed a kinodynamic controller to converge the states of such a two-wheeled mobile robot to the arbitrary target position while avoiding obstacles, by combining the control based on the invariant manifold and the harmonic potential field (HPF). On the other hand, it was confirmed in the previous research that there is a case that the robot cannot avoid the obstacle because there is no enough space to converge the current state to the target state. In this paper, we propose a method that divides the final target position into some sub-target positions and moves the robot step by step, and it is confirmed by the simulation that the robot can converge to the target position while avoiding obstacles using the proposed method.

Manipulation of viscous fingering in a radially tapered cell geometry

NASA Astrophysics Data System (ADS)

Bongrand, Grégoire; Tsai, Peichun Amy

2018-06-01

When a more mobile fluid displaces another immiscible one in a porous medium, viscous fingering propagates with a partial sweep, which hinders oil recovery and soil remedy. We experimentally investigate the feasibility of tuning such fingering propagation in a nonuniform narrow passage with a radial injection, which is widely used in various applications. We show that a radially converging cell can suppress the common viscous fingering observed in a uniform passage, and a full sweep of the displaced fluid is then achieved. The injection flow rate Q can be further exploited to manipulate the viscous fingering instability. For a fixed gap gradient α , our experimental results show a full sweep at a small Q but partial displacement with fingering at a sufficient Q . Finally, by varying α , we identify and characterize the variation of the critical threshold between stable and unstable displacements. Our experimental results reveal good agreement with theoretical predictions by a linear stability analysis.

Five-year results of a randomised controlled trial comparing mobile and fixed bearings in total knee replacement.

PubMed

Breeman, S; Campbell, M K; Dakin, H; Fiddian, N; Fitzpatrick, R; Grant, A; Gray, A; Johnston, L; MacLennan, G S; Morris, R W; Murray, D W

2013-04-01

There is conflicting evidence about the merits of mobile bearings in total knee replacement, partly because most randomised controlled trials (RCTs) have not been adequately powered. We report the results of a multicentre RCT of mobile versus fixed bearings. This was part of the knee arthroplasty trial (KAT), where 539 patients were randomly allocated to mobile or fixed bearings and analysed on an intention-to-treat basis. The primary outcome measure was the Oxford Knee Score (OKS) plus secondary measures including Short Form-12, EuroQol EQ-5D, costs, cost-effectiveness and need for further surgery. There was no significant difference between the groups pre-operatively: mean OKS was 17.18 (sd 7.60) in the mobile-bearing group and 16.49 (sd 7.40) in the fixed-bearing group. At five years mean OKS was 33.19 (sd 16.68) and 33.65 (sd 9.68), respectively. There was no significant difference between trial groups in OKS at five years (-1.12 (95% confidence interval -2.77 to 0.52) or any of the other outcome measures. Furthermore, there was no significant difference in the proportion of patients with knee-related re-operations or in total costs. In this appropriately powered RCT, over the first five years after total knee replacement functional outcomes, re-operation rates and healthcare costs appear to be the same irrespective of whether a mobile or fixed bearing is used.

Mobile-bearing TKA improved the anteroposterior joint stability in mid-flexion range comparing to fixed-bearing TKA.

PubMed

Minoda, Yukihide; Ikebuchi, Mitsuhiko; Mizokawa, Shigekazu; Ohta, Yoichi; Nakamura, Hiroaki

2016-11-01

Proper anteroposterior (AP) joint displacement is an important indicator of good clinical outcome following total knee arthroplasty (TKA). We hypothesized that a newly introduced mobile-bearing posterior stabilized (PS) prosthesis reduces the AP joint displacement. The aim of this study is to compare the AP joint displacement between a newly introduced mobile-bearing PS TKA in one knee and a conventional fixed-bearing PS TKA in other knee. 82 knees in 41 patients who had bilateral TKAs were investigated. All the patients received a conventional fixed-bearing PS prosthesis in one knee and a highly congruent mobile-bearing PS prosthesis in the other knee. AP joint displacement was measured using the KT-2000 arthrometer, at 30° and 75° in flexion, at average of 3.3 years after the operation. AP joint displacements at 30° in flexion were 6 ± 3 mm in the knees with the mobile-bearing PS prosthesis and 9 ± 4 mm in the knee with fixed-bearing PS prosthesis (p < 0.001). AP joint displacements at 75° in flexion were 4 ± 2 mm in the knees with the mobile-bearing PS prosthesis and 6 ± 3 mm in the knee with fixed-bearing PS prosthesis (p < 0.001). This study suggested that the design of the prosthesis can improve the AP joint stability in mid-flexion range.

Migration and clinical outcome of mobile-bearing versus fixed-bearing single-radius total knee arthroplasty

PubMed Central

Van Hamersveld, Koen T; Marang-Van De Mheen, Perla J; Van Der Heide, Huub J L; Van Der Linden-Van Der Zwaag, Henrica M J; Valstar, Edward R; Nelissen, Rob G H H

2018-01-01

Background and purpose Mobile-bearing total knee prostheses (TKPs) were developed in the 1970s in an attempt to increase function and improve implant longevity. However, modern fixed-bearing designs like the single-radius TKP may provide similar advantages. We compared tibial component migration measured with radiostereometric analysis (RSA) and clinical outcome of otherwise similarly designed cemented fixed-bearing and mobile-bearing single-radius TKPs. Patients and methods RSA measurements and clinical scores were assessed in 46 randomized patients at baseline, 6 months, 1 year, and annually thereafter up to 6 years postoperatively. A linear mixed-effects model was used to analyze the repeated measurements. Results Both groups showed comparable migration (p = 0.3), with a mean migration at 6-year follow-up of 0.90 mm (95% CI 0.49–1.41) for the fixed-bearing group compared with 1.22 mm (95% CI 0.75–1.80) for the mobile-bearing group. Clinical outcomes were similar between groups. 1 fixed-bearing knee was revised for aseptic loosening after 6 years and 2 knees (1 in each group) were revised for late infection. 2 knees (1 in each group) were suspected for loosening due to excessive migration. Another mobile-bearing knee was revised after an insert dislocation due to failure of the locking mechanism 6 weeks postoperatively, after which study inclusion was preliminary terminated. Interpretation Fixed-bearing and mobile-bearing single-radius TKPs showed similar migration. The latter may, however, expose patients to more complex surgical techniques and risks such as insert dislocations inherent to this rotating-platform design. PMID:29448880

Early clinical results of a high-flexion, posterior-stabilized, mobile-bearing total knee arthroplasty: a US investigational device exemption trial.

PubMed

Scuderi, Giles R; Hedden, David R; Maltry, John A; Traina, Steven M; Sheinkop, Mitchell B; Hartzband, Mark A

2012-03-01

Between May 2001 and June 2004, 388 total knee arthroplasty cases were enrolled in a prospective, randomized, multicenter investigational device exemption trial. Patients received either the investigational high-flexion mobile-bearing knee or a fixed-bearing control. At 2 to 4 years of follow-up, results in 293 patients with degenerative joint disease were compared using Knee Society Assessment and Function scores, radiographic results, complications analysis, and survival estimates. The mobile-bearing and fixed-bearing groups demonstrated similar, significant improvement over preoperative assessments in Knee Scores, maximum flexion, and range of motion. One mobile-bearing arthroplasty required revision. Radiographic results were unremarkable, and implant-related complications were rare in both groups. At this early follow-up, the investigational high-flexion mobile-bearing knee and its fixed-bearing counterpart demonstrated comparable, effective performance. Copyright © 2012 Elsevier Inc. All rights reserved.

Necessary conditions for weighted mean convergence of Lagrange interpolation for exponential weights

NASA Astrophysics Data System (ADS)

Damelin, S. B.; Jung, H. S.; Kwon, K. H.

2001-07-01

Given a continuous real-valued function f which vanishes outside a fixed finite interval, we establish necessary conditions for weighted mean convergence of Lagrange interpolation for a general class of even weights w which are of exponential decay on the real line or at the endpoints of (-1,1).

Simultaneous quaternion estimation (QUEST) and bias determination

NASA Technical Reports Server (NTRS)

Markley, F. Landis

1989-01-01

Tests of a new method for the simultaneous estimation of spacecraft attitude and sensor biases, based on a quaternion estimation algorithm minimizing Wahba's loss function are presented. The new method is compared with a conventional batch least-squares differential correction algorithm. The estimates are based on data from strapdown gyros and star trackers, simulated with varying levels of Gaussian noise for both inertially-fixed and Earth-pointing reference attitudes. Both algorithms solve for the spacecraft attitude and the gyro drift rate biases. They converge to the same estimates at the same rate for inertially-fixed attitude, but the new algorithm converges more slowly than the differential correction for Earth-pointing attitude. The slower convergence of the new method for non-zero attitude rates is believed to be due to the use of an inadequate approximation for a partial derivative matrix. The new method requires about twice the computational effort of the differential correction. Improving the approximation for the partial derivative matrix in the new method is expected to improve its convergence at the cost of increased computational effort.

In vitro biomechanical comparison after fixed- and mobile-core artificial cervical disc replacement versus fusion

PubMed Central

Lou, Jigang; Li, Yuanchao; Wang, Beiyu; Meng, Yang; Wu, Tingkui; Liu, Hao

2017-01-01

Abstract In vitro biomechanical analysis after cervical disc replacement (CDR) with a novel artificial disc prosthesis (mobile core) was conducted and compared with the intact model, simulated fusion, and CDR with a fixed-core prosthesis. The purpose of this experimental study was to analyze the biomechanical changes after CDR with a novel prosthesis and the differences between fixed- and mobile-core prostheses. Six human cadaveric C2–C7 specimens were biomechanically tested sequentially in 4 different spinal models: intact specimens, simulated fusion, CDR with a fixed-core prosthesis (Discover, DePuy), and CDR with a mobile-core prosthesis (Pretic-I, Trauson). Moments up to 2 Nm with a 75 N follower load were applied in flexion–extension, left and right lateral bending, and left and right axial rotation. The total range of motion (ROM), segmental ROM, and adjacent intradiscal pressure (IDP) were calculated and analyzed in 4 different spinal models, as well as the differences between 2 disc prostheses. Compared with the intact specimens, the total ROM, segmental ROM, and IDP at the adjacent segments showed no significant difference after arthroplasty. Moreover, CDR with a mobile-core prosthesis presented a little higher values of target segment (C5/6) and total ROM than CDR with a fixed-core prosthesis (P > .05). Besides, the difference in IDP at C4/5 after CDR with 2 prostheses was without statistical significance in all the directions of motion. However, the IDP at C6/7 after CDR with a mobile-core prosthesis was lower than CDR with a fixed-core prosthesis in flexion, extension, and lateral bending, with significant difference (P < .05), but not under axial rotation. CDR with a novel prosthesis was effective to maintain the ROM at the target segment and did not affect the ROM and IDP at the adjacent segments. Moreover, CDR with a mobile-core prosthesis presented a little higher values of target segment and total ROM, but lower IDP at the inferior adjacent segment than CDR with a fixed-core prosthesis. PMID:29019902

Particle size and morphology of UHMWPE wear debris in failed total knee arthroplasties--a comparison between mobile bearing and fixed bearing knees.

PubMed

Huang, Chun-Hsiung; Ho, Fang-Yuan; Ma, Hon-Ming; Yang, Chan-Tsung; Liau, Jiann-Jong; Kao, Hung-Chan; Young, Tai-Horng; Cheng, Cheng-Kung

2002-09-01

Osteolysis induced by ultrahigh molecular weight polyethylene wear debris has been recognized as the major cause of long-term failure in total joint arthroplasties. In a previous study, the prevalence of intraoperatively identified osteolysis during primary revision surgery was much higher in mobile bearing knee replacements (47%) than in fixed bearing knee replacements (13%). We postulated that mobile bearing knee implants tend to produce smaller sized particles. In our current study, we compared the particle size and morphology of polyethylene wear debris between failed mobile bearing and fixed bearing knees. Tissue specimens from interfacial and lytic regions were extracted during revision surgery of 10 mobile bearing knees (all of the low contact stress (LCS) design) and 17 fixed bearing knees (10 of the porous-coated anatomic (PCA) and 7 of the Miller/Galante design). Polyethylene particles were isolated from the tissue specimens and examined using both scanning electron microscopy and light-scattering analyses. The LCS mobile bearing knees produced smaller particulate debris (mean equivalent spherical diameter: 0.58 microm in LCS, 1.17 microm in PCA and 5.23 microm in M/G) and more granular debris (mean value: 93% in LCS, 77% in PCA and 15% in M/G).

"A Strategy of Distinction" Unfolds: Unsettling the Undergraduate Outbound Mobility Experience

ERIC Educational Resources Information Center

Sidhu, Ravinder; Dall'Alba, Gloria

2017-01-01

Although short-term mobility programmes are increasingly promoted to university students as sources of competitive advantage, there is little research on academic learnings arising from these initiatives. A "field analysis" of outbound mobility is undertaken to identify convergences and disjunctures between institutional discourses,…

Long-term clinical outcomes and survivorship of press-fit condylar sigma fixed-bearing and mobile-bearing total knee prostheses in the same patients.

PubMed

Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik; Kulkarni, Sourabh S; Kim, Yoon-Hong

2014-10-01

We are aware of no study that has compared press-fit condylar Sigma fixed-bearing and mobile-bearing total knee prostheses in the same patients after more than ten years of follow-up. The purpose of the current study was to compare these two implants with respect to the functional and radiographic results, prevalence of osteolysis, and overall revision rates at a mean of 12.1 years of follow-up. The study consisted of a consecutive series of 444 patients (mean age [and standard deviation], 66.5 ± 7.4 years) who underwent simultaneous bilateral total knee arthroplasty, with one side treated immediately after the other. All of the patients received a press-fit condylar Sigma mobile-bearing prosthesis on one side and a press-fit condylar Sigma fixed-bearing prosthesis on the contralateral side. The minimum duration of follow-up was ten years (mean, 12.1 years; range, ten to thirteen years). At the time of each follow-up visit, the patients were assessed clinically and radiographically. Postoperative total knee scores (95 and 94 points), Western Ontario and McMaster Universities Osteoarthritis Index (19 and 18 points), University of California, Los Angeles activity score (both prostheses, 5 points), range of motion (129° ± 6.3° and 127° ± 6.8°), and radiographic findings did not differ significantly between the press-fit condylar Sigma mobile and fixed-bearing designs at the final follow-up. The prevalence of aseptic loosening (1.4% and 1.8%) did not differ significantly between the mobile and fixed-bearing implant designs. No knee in either group had osteolysis. The estimated survival rate with revision as the end point was 98.2% (95% confidence interval, 91% to 99%) and 97.5% (95% confidence interval, 91% to 99%) at 12.1 years for the mobile and fixed-bearing implant groups, respectively. The results of the present long-term clinical study suggest that excellent clinical and radiographic results were achieved with both the press-fit condylar Sigma mobile and fixed-bearing cruciate-retaining total knee designs. We found no significant clinical advantage for a mobile-bearing over a fixed-bearing total knee prosthesis. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Effect of Mobile Phone Usage on Nickel Ions Release and pH of Saliva in Patients Undergoing Fixed Orthodontic Treatment

PubMed Central

Girme, Tejashree Suresh; Agrawal, Jiwanasha Manish; Agrawal, Manish Suresh; Fulari, Sangamesh Gurunath; Shetti, Shraddha Subhash; Kagi, Vishwal Ajith

2017-01-01

Introduction Hand held mobile phones are presently the most popular means of communication worldwide and have transformed our lives in many aspects. The widespread use of such devices have resulted in growing concerns regarding harmful effects of radiations emitted by them. This study was designed to evaluate the effects of mobile phone usage on nickel ion release as well as pH of saliva in patients with fixed orthodontic appliances. Aim To assess the level of nickel ions in saliva and pH of saliva in mobile phone users undergoing fixed orthodontic treatment using inductively coupled plasma atomic emission spectrometry. Materials and Methods A total of 42 healthy patients with fixed orthodontic appliance in mouth for a duration of six to nine months were selected for the study. They were divided into experimental group (n=21) consisting of mobile phone users and control group (n=21) of non mobile phone users. Saliva samples were collected from both the groups and nickel ion levels were measured using inductively coupled plasma-mass spectroscopy. The pH values were also assessed for both groups using pH meter. Unpaired t-test was used for the data analysis. Results Statistical analysis revealed that though the pH levels were reduced and the nickel ion levels were higher in the experimental group compared to the control group, the results were non significant. Conclusion Mobile phone usage may affect the pH of saliva and result in increased release of nickel ions in saliva of patients with fixed orthodontic appliances in the oral cavity. PMID:29207841

Analogue modeling of rotational orogenic wedges: implications for the Neogene structural evolution of the Southern Central Andes (33°-35°S)

NASA Astrophysics Data System (ADS)

Herrera, S. S.; Farías, M.; Pinto, L.; Yagupsky, D. L.; Guzman, C.; Charrier, R.

2017-12-01

Structural evolution of the southernmost Central Andes is a major subject of debate. Overall vergence within the range and how intra-continental subduction prompts Andean orogeny are controversial topics. Between 33°-35° S, strike of the western slope main structures shifts southwards, from N-S to NNE-SSW, defining the Maipo Orocline. Likely, width of the Principal Cordillera increases southwards. Despite, a progressive southward decrease in orogenic volume has been determined for the segment. To understand such latitudinal variations, and to provide explanations for overall vergence, we carry out analogue models of contractional wedges to explore upper-crustal thrust system development with a progressive variation of the convergence vector. The model setup consisted of a fixed plate on which a mobile plate generated a velocity discontinuity. The upper-crust was simulated using low-cohesive quartz sand. The mobile plate was fixed at its northern end to a pivot, thus progressively incrementing shortening and the obliquity of convergence southwards. PIV photogrammetry recorded wedge evolution. A classical doubly-vergent wedge was formed, consisting of a steep 35° dipping, static thrust on the retro-side, an uplifted core, and an incipient forward-breaking, 25° critically tapered imbricated thrust fan on the pro-side, wider (in plan-view) where the imposed shortening reached the maximum. The resulting wedge is reminiscent of: the steep western Andean slope, in which the bordering thrust has maintained its present position during the Neogene; and the east-vergent fold-and-thrust belt of the eastern slope. The asymmetrical doubly vergence of the model suggests west-directed subduction of the South American continent beneath the orogen. The southward width increase is geometrically comparable to the natural analogue, yet we observe a flat contrast with orogenic shortening and volume estimates for the region. This can be attributed to the fact that uplift and erosion interplay, and the role of pre-Andean structures are not addressed in this approach. Rotation within the model wedge is consistent with paleomagnetic data for the 33°-35°S segment. Nevertheless, our model fails to explain curvature of the Maipo Orocline, suggesting that other lithospheric processes might control bending of the range.

OpenMC In Situ Source Convergence Detection

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

Aldrich, Garrett Allen; Dutta, Soumya; Woodring, Jonathan Lee

2016-05-07

We designed and implemented an in situ version of particle source convergence for the OpenMC particle transport simulator. OpenMC is a Monte Carlo based-particle simulator for neutron criticality calculations. For the transport simulation to be accurate, source particles must converge on a spatial distribution. Typically, convergence is obtained by iterating the simulation by a user-settable, fixed number of steps, and it is assumed that convergence is achieved. We instead implement a method to detect convergence, using the stochastic oscillator for identifying convergence of source particles based on their accumulated Shannon Entropy. Using our in situ convergence detection, we are ablemore » to detect and begin tallying results for the full simulation once the proper source distribution has been confirmed. Our method ensures that the simulation is not started too early, by a user setting too optimistic parameters, or too late, by setting too conservative a parameter.« less

The Nokia Story of Using Action Learning

ERIC Educational Resources Information Center

Ropponen, Timo

2008-01-01

Nokia is the world leader in mobility, driving the transformation and growth of the converging Internet and communications industries. A truly global business, Nokia makes a wide range of mobile devices and provides people with experiences in music, navigation, video, television, imaging, games and business mobility through these devices. Nokia…

75 FR 35989 - Facilitating the Provision of Fixed and Mobile Broadband Access, Educational and Other Advanced...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-24

...] Facilitating the Provision of Fixed and Mobile Broadband Access, Educational and Other Advanced Services in the...), clarifying the requirements necessary for Broadband Radio Service (BRS) and Educational Broadband Service (EBS) licensees to demonstrate substantial service and ensure that BRS licensees of new initial...

Early outcome of TKA with a medial pivot fixed-bearing prosthesis is worse than with a PFC mobile-bearing prosthesis.

PubMed

Kim, Young-Hoo; Yoon, Sung-Hwan; Kim, Jun-Shik

2009-02-01

Although the design features of the Medial Pivot fixed-bearing prosthesis reportedly improve kinematics compared with TKAs using fixed-bearings, clinical improvements have not been reported. We asked whether the clinical and radiographic outcomes, ranges of motion of the knee, patient satisfaction, and complication rates would be better in knees with a Medial Pivot fixed-bearing prosthesis than in those with a PFC Sigma mobile-bearing prosthesis. We compared the results of 92 patients who had a Medial Pivot fixed-bearing prosthesis implanted in one knee and a PFC Sigma mobile-bearing prosthesis implanted in the other. There were 85 women and seven men with a mean age of 69.5 years (range, 55-81 years). The minimum followup was 2 years (mean, 2.6 years; range, 2-3 years). The patients were assessed clinically and radiographically using the rating systems of the Hospital for Special Surgery and the Knee Society at 3 months, 1 year, and annually thereafter. Contrary to expectations, we found worse early clinical outcomes, smaller ranges of knee motion, less patient satisfaction, and a higher complication rate for the Medial Pivot fixed-bearing prosthesis than for the PFC Sigma mobile-bearing prosthesis. Level I, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Global sensitivity analysis for urban water quality modelling: Terminology, convergence and comparison of different methods

NASA Astrophysics Data System (ADS)

Vanrolleghem, Peter A.; Mannina, Giorgio; Cosenza, Alida; Neumann, Marc B.

2015-03-01

Sensitivity analysis represents an important step in improving the understanding and use of environmental models. Indeed, by means of global sensitivity analysis (GSA), modellers may identify both important (factor prioritisation) and non-influential (factor fixing) model factors. No general rule has yet been defined for verifying the convergence of the GSA methods. In order to fill this gap this paper presents a convergence analysis of three widely used GSA methods (SRC, Extended FAST and Morris screening) for an urban drainage stormwater quality-quantity model. After the convergence was achieved the results of each method were compared. In particular, a discussion on peculiarities, applicability, and reliability of the three methods is presented. Moreover, a graphical Venn diagram based classification scheme and a precise terminology for better identifying important, interacting and non-influential factors for each method is proposed. In terms of convergence, it was shown that sensitivity indices related to factors of the quantity model achieve convergence faster. Results for the Morris screening method deviated considerably from the other methods. Factors related to the quality model require a much higher number of simulations than the number suggested in literature for achieving convergence with this method. In fact, the results have shown that the term "screening" is improperly used as the method may exclude important factors from further analysis. Moreover, for the presented application the convergence analysis shows more stable sensitivity coefficients for the Extended-FAST method compared to SRC and Morris screening. Substantial agreement in terms of factor fixing was found between the Morris screening and Extended FAST methods. In general, the water quality related factors exhibited more important interactions than factors related to water quantity. Furthermore, in contrast to water quantity model outputs, water quality model outputs were found to be characterised by high non-linearity.

Performance of time-varying predictors in multilevel models under an assumption of fixed or random effects.

PubMed

Baird, Rachel; Maxwell, Scott E

2016-06-01

Time-varying predictors in multilevel models are a useful tool for longitudinal research, whether they are the research variable of interest or they are controlling for variance to allow greater power for other variables. However, standard recommendations to fix the effect of time-varying predictors may make an assumption that is unlikely to hold in reality and may influence results. A simulation study illustrates that treating the time-varying predictor as fixed may allow analyses to converge, but the analyses have poor coverage of the true fixed effect when the time-varying predictor has a random effect in reality. A second simulation study shows that treating the time-varying predictor as random may have poor convergence, except when allowing negative variance estimates. Although negative variance estimates are uninterpretable, results of the simulation show that estimates of the fixed effect of the time-varying predictor are as accurate for these cases as for cases with positive variance estimates, and that treating the time-varying predictor as random and allowing negative variance estimates performs well whether the time-varying predictor is fixed or random in reality. Because of the difficulty of interpreting negative variance estimates, 2 procedures are suggested for selection between fixed-effect and random-effect models: comparing between fixed-effect and constrained random-effect models with a likelihood ratio test or fitting a fixed-effect model when an unconstrained random-effect model produces negative variance estimates. The performance of these 2 procedures is compared. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Evolution families of conformal mappings with fixed points and the Löwner-Kufarev equation

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

Goryainov, V V

2015-01-31

The paper is concerned with evolution families of conformal mappings of the unit disc to itself that fix an interior point and a boundary point. Conditions are obtained for the evolution families to be differentiable, and an existence and uniqueness theorem for an evolution equation is proved. A convergence theorem is established which describes the topology of locally uniform convergence of evolution families in terms of infinitesimal generating functions. The main result in this paper is the embedding theorem which shows that any conformal mapping of the unit disc to itself with two fixed points can be embedded into a differentiable evolution familymore » of such mappings. This result extends the range of the parametric method in the theory of univalent functions. In this way the problem of the mutual change of the derivative at an interior point and the angular derivative at a fixed point on the boundary is solved for a class of mappings of the unit disc to itself. In particular, the rotation theorem is established for this class of mappings. Bibliography: 27 titles.« less

Phonon-limited carrier mobility and resistivity from carbon nanotubes to graphene

NASA Astrophysics Data System (ADS)

Li, Jing; Miranda, Henrique Pereira Coutada; Niquet, Yann-Michel; Genovese, Luigi; Duchemin, Ivan; Wirtz, Ludger; Delerue, Christophe

2015-08-01

Under which conditions do the electrical transport properties of one-dimensional (1D) carbon nanotubes (CNTs) and 2D graphene become equivalent? We have performed atomistic calculations of the phonon-limited electrical mobility in graphene and in a wide range of CNTs of different types to address this issue. The theoretical study is based on a tight-binding method and a force-constant model from which all possible electron-phonon couplings are computed. The electrical resistivity of graphene is found in very good agreement with experiments performed at high carrier density. A common methodology is applied to study the transition from one to two dimensions by considering CNTs with diameter up to 16 nm. It is found that the mobility in CNTs of increasing diameter converges to the same value, i.e., the mobility in graphene. This convergence is much faster at high temperature and high carrier density. For small-diameter CNTs, the mobility depends strongly on chirality, diameter, and the existence of a band gap.

47 CFR 5.61 - Procedure for obtaining a special temporary authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Office of Engineering and Technology Web site https://gullfoss2.fcc.gov/prod/oet/cf/els/index.cfm effective January 1, 2004 and shall contain the following information: (1) Name, address, phone number (also... proposed operation. (5) Class(es) of station (fixed, mobile, fixed and mobile) and call sign of station (if...

Self-deployable mobile sensor networks for on-demand surveillance

NASA Astrophysics Data System (ADS)

Miao, Lidan; Qi, Hairong; Wang, Feiyi

2005-05-01

This paper studies two interconnected problems in mobile sensor network deployment, the optimal placement of heterogeneous mobile sensor platforms for cost-efficient and reliable coverage purposes, and the self-organizable deployment. We first develop an optimal placement algorithm based on a "mosaicked technology" such that different types of mobile sensors form a mosaicked pattern uniquely determined by the popularity of different types of sensor nodes. The initial state is assumed to be random. In order to converge to the optimal state, we investigate the swarm intelligence (SI)-based sensor movement strategy, through which the randomly deployed sensors can self-organize themselves to reach the optimal placement state. The proposed algorithm is compared with the random movement and the centralized method using performance metrics such as network coverage, convergence time, and energy consumption. Simulation results are presented to demonstrate the effectiveness of the mosaic placement and the SI-based movement.

Low cost satellite land mobile service for nationwide applications

NASA Technical Reports Server (NTRS)

Weiss, J. A.

1978-01-01

A satellite land mobile system using mobile radios in the UHF band, and Ku-band Communications Routing Terminals (earth stations) for a nationwide connection from any mobile location to any fixed or mobile location, and from any fixed location to any mobile location is proposed. The proposed nationwide satellite land mobile service provides: telephone network quality (1 out of 100 blockage) service, complete privacy for all the users, operation similar to the telephone network, alternatives for data services up to 32 Kbps data rates, and a cost effective and practical mobile radio compatible with system sizes ranging from 10,000 to 1,000,000 users. Seven satellite alternatives (ranging from 30 ft diameter dual beam antenna to 210 ft diameter 77 beam antenna) along with mobile radios having a sensitivity figure of merit (G/T) of -15 dB/deg K are considered. Optimized mobile radio user costs are presented as a function of the number of users with the satellite and mobile radio alternatives as system parameters.

Mental rotation of body parts and sensory temporal discrimination in fixed dystonia.

PubMed

Katschnig, Petra; Edwards, Mark J; Schwingenschuh, Petra; Aguirregomozcorta, Maria; Kägi, Georg; Rothwell, John C; Bhatia, Kailash P

2010-06-15

Fixed dystonia is an uncommon but severely disabling condition typically affecting young women following a minor peripheral injury. There is no evidence of any structural lesions of the central nervous system nor any clear peripheral nerve or root damage. Electrophysiological techniques such as short intracortical inhibition, cortical silent period and a plasticity inducing protocol have revealed similarities but also differences compared to classical mobile dystonia. To further explore the pathophysiology of fixed dystonia we compared mental rotation of body parts and sensory temporal discrimination in 11 patients with fixed dystonia, 11 patients with classical mobile dystonia and 10 healthy controls. In the mental rotation task subjects were presented with realistic photos of left or right hands, feet and the head of a young women with a black patch covering the left or the right eye in six different orientations. Subjects had to verbally report the laterality of the presented stimuli. To assess sensory temporal discrimination subjects were asked to discriminate whether pairs of visual, tactile (electrical), or visuo-tactile stimuli were simultaneous or sequential (temporal discrimination threshold) and in the latter case which stimulus preceded the other (temporal order judgement). In accordance with previous studies patients with mobile dystonia were abnormal in mental rotation and temporal discrimination, whereas patients with fixed dystonia were only impaired in mental rotation. Possible explanations for this deficit may include the influence of the abnormal body posture itself, a shared predisposing pathophysiology for mobile and fixed dystonia, or a body image disturbance. These findings add information to the developing pathophysiological picture of fixed dystonia. (c) 2010 Movement Disorder Society.

No difference in terms of radiostereometric analysis between fixed- and mobile-bearing total knee arthroplasty: a randomized, single-blind, controlled trial.

PubMed

Schotanus, M G M; Pilot, P; Kaptein, B L; Draijer, W F; Tilman, P B J; Vos, R; Kort, N P

2017-09-01

A concern that arises with any new prosthesis is whether it will achieve satisfactory long-term implant stability. The gold standard of assessing the quality of fixation in a new or relatively new implant is to undertake a randomized controlled trial using radiostereometric analysis. It was hypothesized that both mobile-bearing total knee arthroplasty and fixed-bearing total knee arthroplasty have comparable migration patterns at 2-year follow-up. This study investigated two types of cemented total knee arthroplasty, the mobile- or fixed-bearing variant from the same family with use of radiostereometric analysis. This prospective, patient-blinded, randomized, controlled trial was designed to investigate early migration of the tibia component after two years of follow-up with use of radiostereometric analysis. A total of 50 patients were randomized to receive a mobile- or fixed-bearing TKA from the same family. Patients were evaluated during 2-year follow-up, including radiostereometric analysis, physical and clinical examination and patient reported outcome measures (PROMs). At two-year follow-up, the mean (±SD) maximum total point motion (MTPM) in the fixed-bearing group was 0.82 (±1.16) versus 0.92 mm (±0.64) in the mobile-bearing group (p = n.s) with the largest migration seen during the first 6 weeks (0.45 ± 0.32 vs. 0.54 ± 0.30). The clinical outcome and PROMs significantly improved within each group, not between both groups. Measuring early micromotion is useful for predicting clinical loosening that can lead to revision. The results of this study demonstrate that early migration of the mobile-bearing is similar to that of the fixed-bearing component at two years and was mainly seen in the first weeks after implantation. Randomized, single-blind, controlled trial, Level I.

Dynamic transition between fixed- and mobile-bed: mathematical and numerical aspects

NASA Astrophysics Data System (ADS)

Zugliani, Daniel; Pasqualini, Matteo; Rosatti, Giorgio

2017-04-01

Free-surface flows with high sediment transport (as debris flow or hyper-concentrated flow) are composed by a mixture of fluid and solid phase, usually water and sediment. When these flows propagate over loose beds, particles constituting the mixture of water and sediments strongly interact with the ones forming the bed, leading to erosion or deposition. However, there are lots of other situations when the mixture flows over rigid bedrocks or over artificially paved transects, so there is no mass exchange between bed and mixture. The two situations are usually referred to as, respectively, mobile- and fixed-bed conditions. From a mathematical point of view, the systems of Partial Differential Equations (PDEs) that describe these flows derive from mass and momentum balance of both phases, but, the two resulting PDEs systems are different. The main difference concerns the concentration: in the mobile-bed condition, the concentration is linked to the local flow conditions by means of a suitable rheological relation, while in the fixed-bed case, the concentration is an unknown of the problem. It is quite common that a free surface flow with high sediment transport, in its path, encounters both conditions. In the recent work of Rosatti & Zugliani 2015, the mathematical and numerical description of the transition between fixed- and mobile-bed was successfully resolved, for the case of low sediment transport phenomena, by the introduction of a suitable erodibility variable and satisfactory results were obtained. The main disadvantage of the approach is related to the erodibility variable, that changes in space, based on bed characteristics, but remains constant in time. However, the nature of the bed can change dynamically as result of deposition over fixed bed or high erosion over mobile bed. With this work, we extend the applicability of the mentioned approach to the more complex PDEs describing the hyper-concentrated flow. Moreover, we introduce a strategy that allows a dynamic time variation of the erodibility variable. The issue of the dynamic transition between fixed- and mobile-bed condition is tackled, from a numerical point of view, using a particular predictor corrector technique that compare the transported concentration related with the fixed bed and the equilibrium concentration, deriving from a closure relation, associated to the mobile bed condition. Through a comparison between exact solution, built using the generalized Rankine - Hugoniot condition, and the numeric results, we highlight capabilities and limits of this enhanced technique. Bibliography: G. Rosatti and D. Zugliani, 2015. "Modelling the transition between fixed and mobile bed conditions in two-phase free-surface flows: The Composite Riemann Problem and its numerical solution". Journal of Computational Physics, 285:226-250

The Roles of Visualization and Symbolism in the Potential and Actual Infinity of the Limit Process

ERIC Educational Resources Information Center

Kidron, Ivy; Tall, David

2015-01-01

A teaching experiment-using Mathematica to investigate the convergence of sequence of functions visually as a sequence of objects (graphs) converging onto a fixed object (the graph of the limit function)-is here used to analyze how the approach can support the dynamic blending of visual and symbolic representations that has the potential to lead…

Electrophoretic cell separation by means of microspheres

NASA Technical Reports Server (NTRS)

Smolka, A. J. K.; Nerren, B. H.; Margel, S.; Rembaum, A.

1979-01-01

The electrophoretic mobility of fixed human erythrocytes immunologically labeled with poly(vinylpyridine) or poly(glutaraldehyde) microspheres was reduced by approximately 40%. This observation was utilized in preparative scale electrophoretic separations of fixed human and turkey erythrocytes, the mobilities of which under normal physiological conditions do not differ sufficiently to allow their separation by continuous flow electrophoresis. We suggest that resolution in the electrophoretic separation of cell subpopulations, currently limited by finite and often overlapping mobility distributions, may be significantly enhanced by immunospecific labeling of target populations using microspheres.

Application of Fiber-Optical Techniques in the Access Transmission and Backbone Transport of Mobile Networks

NASA Astrophysics Data System (ADS)

Hilt, Attila; Pozsonyi, László

2012-09-01

Fixed access networks widely employ fiber-optical techniques due to the extremely wide bandwidth offered to subscribers. In the last decade, there has also been an enormous increase of user data visible in mobile systems. The importance of fiber-optical techniques within the fixed transmission/transport networks of mobile systems is therefore inevitably increasing. This article summarizes a few reasons and gives examples why and how fiber-optic techniques are employed efficiently in second-generation networks.

Strong Convergence for a Finite Family of Generalized Asymptotically Nonexpansive Mappings

NASA Astrophysics Data System (ADS)

Ma, Zhi-Hong; Chen, Ru-Dond

The purpose of this paper is to show the convergence theorems for generalized asymptotically nonexpansive mappings and asymptotically nonexpansive mappings in Banach spaces by using a new iteration which is a natural generalization of the implicit iteration. In the meantime, we give the necessary and sufficient conditions of the strong convergence to approximate a common fixed point and modify some flaw in the results of Thakur [11]. As one will see, the results presented in this paper are an extension of the corresponding results [8,11].

Perspectives of Mobile Versus Fixed Mammography in Santa Clara County, California: A Focus Group Study.

PubMed

Chen, Yi-Ren; Chang-Halpenny, Christine; Kumarasamy, Narmadan A; Venegas, Angela; Braddock Iii, Clarence H

2016-02-12

Our aim was to examine underserved women's perceptions on mobile versus fixed mammography in Santa Clara, California through a focus group study.  Research has shown that medically underserved women have higher breast cancer mortality rates correlated with under-screening and a disproportional rate of late-stage diagnosis. The Community Health Partnership in Santa Clara County, California runs the Community Mammography Access Project (CMAP) that targets nearly 20,000 medically underserved women over the age of 40 in the county through the collaborative effort of an existing safety net of healthcare providers. However, little data exists on the advantages or disadvantages of mobile mammography units from the patient perspective.   We assessed underserved women's perspectives on mammography services in Santa Clara County through two focus groups from women screened at mobile or fixed site programs. Patients were recruited from both CMAP clinics and a county hospital, and focus group data were analyzed using content analysis.  We found that women from both the mobile and fixed sites shared similar motivating factors for getting a mammogram. Both groups recognized that screening was uncomfortable but necessary for good health and had positive feedback about their personal physicians. However, mobile participants, in particular, appreciated the atmosphere of mobile screening, reported shorter wait times, and remarked on the good communication from the clinic staff and empathetic treatment they received. However, mobile participants also expressed concern about the quality of films at mobile sites due to delayed initial reading of the films.   Mobile mammography offers a unique opportunity for women of underserved populations to access high satisfaction screenings, and it encourages a model similar to CMAP in other underserved areas. However, emphasis should be placed on providing a warm and welcoming environment for patients and ensuring the quality of mammography images.

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

An Efficient MCMC Algorithm to Sample Binary Matrices with Fixed Marginals

ERIC Educational Resources Information Center

Verhelst, Norman D.

2008-01-01

Uniform sampling of binary matrices with fixed margins is known as a difficult problem. Two classes of algorithms to sample from a distribution not too different from the uniform are studied in the literature: importance sampling and Markov chain Monte Carlo (MCMC). Existing MCMC algorithms converge slowly, require a long burn-in period and yield…

Mobile-bearing knees reduce rotational asymmetric wear.

PubMed

Ho, Fang-Yuan; Ma, Hon-Ming; Liau, Jiann-Jong; Yeh, Chuan-Ren; Huang, Chun-Hsiung

2007-09-01

Polyethylene wear of bearing components is the most common long-term complication in total knee arthroplasty. One would anticipate differing kinematics would generate different wear patterns (including wear type, degree, and symmetry) on the articulating surface of mobile-bearing and fixed-bearing inserts. Because mobile-bearing designs facilitate movement of the insert relative to the tray when the knee rotates, we hypothesized mobile-bearing designs would reduce the incidence of rotational asymmetric wear. We examined 51 worn tibial inserts, including 15 from mobile-bearing rotating-platform posterior-cruciate-sacrificing dished prostheses and 36 from fixed-bearing posterior-cruciate-retaining flat prostheses, which were retrieved at revision surgery with an average implantation time of 115 months. We divided wear types into low-grade wear (burnishing, abrasion, and cold flow) and high-grade wear (scratching, pitting, metal embedding, and delamination) to assess wear degree of polyethylene. To assess symmetry of wear, the insert surface was divided into medial and lateral sides and each side was further divided into three equal zones along the anteroposterior direction. Low-grade wear was more common in mobile-bearing knees, whereas high-grade wear was more common in fixed-bearing knees. We identified no internal/external rotational asymmetric wear or anteroposterior asymmetric wear in mobile-bearing knees.

High-throughput and low-latency 60GHz small-cell network architectures over radio-over-fiber technologies

NASA Astrophysics Data System (ADS)

Pleros, N.; Kalfas, G.; Mitsolidou, C.; Vagionas, C.; Tsiokos, D.; Miliou, A.

2017-01-01

Future broadband access networks in the 5G framework will need to be bilateral, exploiting both optical and wireless technologies. This paper deals with new approaches and synergies on radio-over-fiber (RoF) technologies and how those can be leveraged to seamlessly converge wireless technology for agility and mobility with passive optical networks (PON)-based backhauling. The proposed convergence paradigm is based upon a holistic network architecture mixing mm-wave wireless access with photonic integration, dynamic capacity allocation and network coding schemes to enable high bandwidth and low-latency fixed and 60GHz wireless personal area communications for gigabit rate per user, proposing and deploying on top a Medium-Transparent MAC (MT-MAC) protocol as a low-latency bandwidth allocation mechanism. We have evaluated alternative network topologies between the central office (CO) and the access point module (APM) for data rates up to 2.5 Gb/s and SC frequencies up to 60 GHz. Optical network coding is demonstrated for SCM-based signaling to enhance bandwidth utilization and facilitate optical-wireless convergence in 5G applications, reporting medium-transparent network coding directly at the physical layer between end-users communicating over a RoF infrastructure. Towards equipping the physical layer with the appropriate agility to support MT-MAC protocols, a monolithic InP-based Remote Antenna Unit optoelectronic PIC interface is shown that ensures control over the optical resource allocation assisting at the same time broadband wireless service. Finally, the MT-MAC protocol is analysed and simulation and analytical theoretical results are presented that are found to be in good agreement confirming latency values lower than 1msec for small- to mid-load conditions.

Channel simulation to facilitate mobile-satellite communications research

NASA Technical Reports Server (NTRS)

Davarian, Faramaz

1987-01-01

The mobile-satellite-service channel simulator, which is a facility for an end-to-end hardware simulation of mobile satellite communications links is discussed. Propagation effects, Doppler, interference, band limiting, satellite nonlinearity, and thermal noise have been incorporated into the simulator. The propagation environment in which the simulator needs to operate and the architecture of the simulator are described. The simulator is composed of: a mobile/fixed transmitter, interference transmitters, a propagation path simulator, a spacecraft, and a fixed/mobile receiver. Data from application experiments conducted with the channel simulator are presented; the noise converison technique to evaluate interference effects, the error floor phenomenon of digital multipath fading links, and the fade margin associated with a noncoherent receiver are examined. Diagrams of the simulator are provided.

Operation of remote mobile sensors for security of drinking water distribution systems.

PubMed

Perelman, By Lina; Ostfeld, Avi

2013-09-01

The deployment of fixed online water quality sensors in water distribution systems has been recognized as one of the key components of contamination warning systems for securing public health. This study proposes to explore how the inclusion of mobile sensors for inline monitoring of various water quality parameters (e.g., residual chlorine, pH) can enhance water distribution system security. Mobile sensors equipped with sampling, sensing, data acquisition, wireless transmission and power generation systems are being designed, fabricated, and tested, and prototypes are expected to be released in the very near future. This study initiates the development of a theoretical framework for modeling mobile sensor movement in water distribution systems and integrating the sensory data collected from stationary and non-stationary sensor nodes to increase system security. The methodology is applied and demonstrated on two benchmark networks. Performance of different sensor network designs are compared for fixed and combined fixed and mobile sensor networks. Results indicate that complementing online sensor networks with inline monitoring can increase detection likelihood and decrease mean time to detection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Equivalent source modeling of the core magnetic field using magsat data

NASA Technical Reports Server (NTRS)

Mayhew, M. A.; Estes, R. H.

1983-01-01

Experiments are carried out on fitting the main field using different numbers of equivalent sources arranged in equal area at fixed radii at and inside the core-mantle boundary. In fixing the radius for a given series of runs, the convergence problems that result from the extreme nonlinearity of the problem when dipole positions are allowed to vary are avoided. Results are presented from a comparison between this approach and the standard spherical harmonic approach for modeling the main field in terms of accuracy and computational efficiency. The modeling of the main field with an equivalent dipole representation is found to be comparable to the standard spherical harmonic approach in accuracy. The 32 deg dipole density (42 dipoles) corresponds approximately to an eleventh degree/order spherical harmonic expansion (143 parameters), whereas the 21 dipole density (92 dipoles) corresponds to approximately a seventeenth degree and order expansion (323 parameters). It is pointed out that fixing the dipole positions results in rapid convergence of the dipole solutions for single-epoch models.

Comparison of ultra-congruent mobile- and fixed-bearing navigation-assisted total knee arthroplasty with minimum 5-year follow-up.

PubMed

Kim, Seong Hwan; Lim, Jung-Won; Ko, Young-Bong; Song, Min-Gu; Lee, Han-Jun

2016-11-01

The purpose of this study was to compare the midterm outcomes between fixed and mobile ultra-congruent (UC) bearings in total knee arthroplasty (TKA). This is a retrospective matched-pairs case-control study of patients who underwent primary navigation-assisted TKA with a minimum 5-year follow-up. A total of 182 cases involved the fixed UC bearing system as Group 1 and 101 cases involved mobile UC bearing system group as Group 2. After 1:1 matching, 73 knees in each group were enrolled. Clinical and radiographic outcomes were evaluated. The overall survival was 143 of 146 cases (97.9 %) at final follow-up, and 72 of 73 cases (96.3 %) in Group 1 and 71 of 73 cases (95.8 %) in Group 2 at final follow-up based on an endpoint of revision surgery. The reasons of revision TKA were periprosthetic fracture in Group 1, infection and bearing dislocation in Group 2. There was no statistical difference in Hospital for Special Surgery (HSS) scores, Knee Society Scores (KSS), WOMAC index score evaluations between groups. This study demonstrated that the fixed-bearing UC prosthesis could provide satisfactory performance compared with that of the mobile-bearing UC prosthesis with minimum 5-year follow-up. The fixed-bearing UC prosthesis could be considered in navigation-assisted TKA with theoretical advantages of UC design. IV.

NUMERICAL CONVERGENCE IN SMOOTHED PARTICLE HYDRODYNAMICS

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

Zhu, Qirong; Li, Yuexing; Hernquist, Lars

2015-02-10

We study the convergence properties of smoothed particle hydrodynamics (SPH) using numerical tests and simple analytic considerations. Our analysis shows that formal numerical convergence is possible in SPH only in the joint limit N → ∞, h → 0, and N{sub nb} → ∞, where N is the total number of particles, h is the smoothing length, and N{sub nb} is the number of neighbor particles within the smoothing volume used to compute smoothed estimates. Previous work has generally assumed that the conditions N → ∞ and h → 0 are sufficient to achieve convergence, while holding N{sub nb} fixed.more » We demonstrate that if N{sub nb} is held fixed as the resolution is increased, there will be a residual source of error that does not vanish as N → ∞ and h → 0. Formal numerical convergence in SPH is possible only if N{sub nb} is increased systematically as the resolution is improved. Using analytic arguments, we derive an optimal compromise scaling for N{sub nb} by requiring that this source of error balance that present in the smoothing procedure. For typical choices of the smoothing kernel, we find N{sub nb} ∝N {sup 0.5}. This means that if SPH is to be used as a numerically convergent method, the required computational cost does not scale with particle number as O(N), but rather as O(N {sup 1} {sup +} {sup δ}), where δ ≈ 0.5, with a weak dependence on the form of the smoothing kernel.« less

Analogue modelling of inclined, brittle-ductile transpression: Testing analytical models through natural shear zones (external Betics)

NASA Astrophysics Data System (ADS)

Barcos, L.; Díaz-Azpiroz, M.; Balanyá, J. C.; Expósito, I.; Jiménez-Bonilla, A.; Faccenna, C.

2016-07-01

The combination of analytical and analogue models gives new opportunities to better understand the kinematic parameters controlling the evolution of transpression zones. In this work, we carried out a set of analogue models using the kinematic parameters of transpressional deformation obtained by applying a general triclinic transpression analytical model to a tabular-shaped shear zone in the external Betic Chain (Torcal de Antequera massif). According to the results of the analytical model, we used two oblique convergence angles to reproduce the main structural and kinematic features of structural domains observed within the Torcal de Antequera massif (α = 15° for the outer domains and α = 30° for the inner domain). Two parallel inclined backstops (one fixed and the other mobile) reproduce the geometry of the shear zone walls of the natural case. Additionally, we applied digital particle image velocimetry (PIV) method to calculate the velocity field of the incremental deformation. Our results suggest that the spatial distribution of the main structures observed in the Torcal de Antequera massif reflects different modes of strain partitioning and strain localization between two domain types, which are related to the variation in the oblique convergence angle and the presence of steep planar velocity - and rheological - discontinuities (the shear zone walls in the natural case). In the 15° model, strain partitioning is simple and strain localization is high: a single narrow shear zone is developed close and parallel to the fixed backstop, bounded by strike-slip faults and internally deformed by R and P shears. In the 30° model, strain partitioning is strong, generating regularly spaced oblique-to-the backstops thrusts and strike-slip faults. At final stages of the 30° experiment, deformation affects the entire model box. Our results show that the application of analytical modelling to natural transpressive zones related to upper crustal deformation facilitates to constrain the geometrical parameters of analogue models.

Electrophoretic cell separation by means of immunomicrospheres

NASA Technical Reports Server (NTRS)

Rembaum, A.; Smolka, A. J. K.

1980-01-01

The electrophoretic mobility of fixed human red blood cells immunologically labeled with polymeric (4-vinyl)pyridine or polyglutaraldehyde microspheres was altered to a considerable extent. This observation was utilized in the preparative scale electrophoretic separation of human and turkey fixed red blood cells, whose mobilities under normal physiological conditions do not differ sufficiently to allow their separation by continuous flow electrophoresis. It is suggested that resolution in the electrophoretic separation of cell subpopulations, currently limited by finite and often overlapping mobility distributions, may be significantly enhanced by immuno-specific labeling of target populations using microspheres.

Real-Time Feedback Control of Flow-Induced Cavity Tones. Part 2; Adaptive Control

NASA Technical Reports Server (NTRS)

Kegerise, M. A.; Cabell, R. H.; Cattafesta, L. N., III

2006-01-01

An adaptive generalized predictive control (GPC) algorithm was formulated and applied to the cavity flow-tone problem. The algorithm employs gradient descent to update the GPC coefficients at each time step. Past input-output data and an estimate of the open-loop pulse response sequence are all that is needed to implement the algorithm for application at fixed Mach numbers. Transient measurements made during controller adaptation revealed that the controller coefficients converged to a steady state in the mean, and this implies that adaptation can be turned off at some point with no degradation in control performance. When converged, the control algorithm demonstrated multiple Rossiter mode suppression at fixed Mach numbers ranging from 0.275 to 0.38. However, as in the case of fixed-gain GPC, the adaptive GPC performance was limited by spillover in sidebands around the suppressed Rossiter modes. The algorithm was also able to maintain suppression of multiple cavity tones as the freestream Mach number was varied over a modest range (0.275 to 0.29). Beyond this range, stable operation of the control algorithm was not possible due to the fixed plant model in the algorithm.

Sagittal tibiotalar translation and clinical outcomes in mobile and fixed-bearing total ankle replacement.

PubMed

Usuelli, Federico G; Manzi, Luigi; Brusaferri, Giovanni; Neher, Robert E; Guelfi, Matteo; Maccario, Camilla

2017-06-01

Sagittal implant malalignment after total ankle replacement (TAR) has been considered to be a possible cause for premature implant failure. In a prior study, the change over time of the tibiotalar ratio (T-T ratio), which is the ratio between the posterior longitudinal talar length and the full longitudinal talar length, was assessed in 66 TARs where an unconstrained, mobile-bearing implant was implanted. The analysis documented an increase in the T-T ratio between 2 and 6 months post-surgery (on average from 34.6% to 37.2%). We hypothesized that this change might have been related to the presence of a mobile-bearing insert. In order to test our hypothesis, we designed a study to compare the translation of the talus in TARs performed with an unconstrained, mobile-bearing implant (designated the "Mobile ankle") and those performed with a semi-constrained, fixed-bearing implant (designated the "Fixed ankle"). The study included 71 consecutive patients (71 ankles) who underwent TAR with the Mobile ankle and 24 consecutive patients (24 ankles) who received the Fixed ankle from May 2011 to December 2014. Patients were assessed clinically and radiologically preoperatively (T 0 ), at 6 months (T 2 ) and 12 months (T 3 ) post-surgery. There was also a radiological assessment at 2 months post-surgery (T 1 ). The comparison of the T-T ratio between the two implant groups and over time indicated an interaction between time and group, therefore the changes of the T-T ratio over time were affected by the implant type factor (P<0.001). The changes of the postoperative T-T ratio over time were not significant in the Fixed ankle group (35.7±6.7% at T 1 , T 2 , and T 3 ; P=1.0 for each pairwise comparison). In the Mobile ankle group, the T-T ratio at 2 months (34.4±5.5%) was significantly different to the T-T ratio at 6 months (37.0±5.8%; P<0.001; i.e. there was a significant posterior translation of the talus). The AOFAS score increased from preop to 12 months post-surgery in both the Mobile ankle (72.7±12.8 at 12 months; P<0.001) and the Fixed ankle (85.0±9.7 at 12 months; P<0.001). The significant posterior translation of the talus from 2 to 6 months documented only in the Mobile ankle group may have been associated with the presence of the mobile bearing interface. Copyright © 2016 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Problematic Smartphone Use: Investigating Contemporary Experiences Using a Convergent Design

PubMed Central

Harkin, Lydia

2018-01-01

Internet-enabled smartphones are increasingly ubiquitous in the Western world. Research suggests a number of problems can result from mobile phone overuse, including dependence, dangerous and prohibited use. For over a decade, this has been measured by the Problematic Mobile Phone Use Questionnaire (PMPU-Q). Given the rapid developments in mobile technologies, changes of use patterns and possible problematic and addictive use, the aim of the present study was to investigate and validate an updated contemporary version of the PMPU-Q (PMPU-Q-R). A mixed methods convergent design was employed, including a psychometric survey (N = 512) alongside qualitative focus groups (N = 21), to elicit experiences and perceptions of problematic smartphone use. The results suggest the PMPU-Q-R factor structure can be updated to include smartphone dependence, dangerous driving, and antisocial smartphone use factors. Theories of problematic mobile phone use require consideration of the ubiquity and indispensability of smartphones in the present day and age, particularly regarding use whilst driving and in social interactions. PMID:29337883

Problematic Smartphone Use: Investigating Contemporary Experiences Using a Convergent Design.

PubMed

Kuss, Daria J; Harkin, Lydia; Kanjo, Eiman; Billieux, Joel

2018-01-16

Internet-enabled smartphones are increasingly ubiquitous in the Western world. Research suggests a number of problems can result from mobile phone overuse, including dependence, dangerous and prohibited use. For over a decade, this has been measured by the Problematic Mobile Phone Use Questionnaire (PMPU-Q). Given the rapid developments in mobile technologies, changes of use patterns and possible problematic and addictive use, the aim of the present study was to investigate and validate an updated contemporary version of the PMPU-Q (PMPU-Q-R). A mixed methods convergent design was employed, including a psychometric survey ( N = 512) alongside qualitative focus groups ( N = 21), to elicit experiences and perceptions of problematic smartphone use. The results suggest the PMPU-Q-R factor structure can be updated to include smartphone dependence, dangerous driving, and antisocial smartphone use factors. Theories of problematic mobile phone use require consideration of the ubiquity and indispensability of smartphones in the present day and age, particularly regarding use whilst driving and in social interactions.

Consensus in evolving networks of mobile agents

NASA Astrophysics Data System (ADS)

Baronchelli, Andrea; Díaz-Guilera, Albert

2012-02-01

Populations of mobile and communicating agents describe a vast array of technological and natural systems, ranging from sensor networks to animal groups. Here, we investigate how a group-level agreement may emerge in the continuously evolving networks defined by the local interactions of the moving individuals. We adopt a general scheme of motion in two dimensions and we let the individuals interact through the minimal naming game, a prototypical scheme to investigate social consensus. We distinguish different regimes of convergence determined by the emission range of the agents and by their mobility, and we identify the corresponding scaling behaviors of the consensus time. In the same way, we rationalize also the behavior of the maximum memory used during the convergence process, which determines the minimum cognitive/storage capacity needed by the individuals. Overall, we believe that the simple and general model presented in this talk can represent a helpful reference for a better understanding of the behavior of populations of mobile agents.

Consensus in networks of mobile communicating agents

NASA Astrophysics Data System (ADS)

Baronchelli, Andrea; Díaz-Guilera, Albert

2012-01-01

Populations of mobile and communicating agents describe a vast array of technological and natural systems, ranging from sensor networks to animal groups. Here, we investigate how a group-level agreement may emerge in the continuously evolving network defined by the local interactions of the moving individuals. We adopt a general scheme of motion in two dimensions and we let the individuals interact through the minimal naming game, a prototypical scheme to investigate social consensus. We distinguish different regimes of convergence determined by the emission range of the agents and by their mobility, and we identify the corresponding scaling behaviors of the consensus time. In the same way, we rationalize also the behavior of the maximum memory used during the convergence process, which determines the minimum cognitive/storage capacity needed by the individuals. Overall, we believe that the simple and general model presented in this paper can represent a helpful reference for a better understanding of the behavior of populations of mobile agents.

Perturbation analysis of the limit cycle of the free van der Pol equation

NASA Technical Reports Server (NTRS)

Dadfar, M. B.; Geer, J.; Anderson, C. M.

1983-01-01

A power series expansion in the damping parameter, epsilon, of the limit cycle of the free van der Pol equation is constructed and analyzed. Coefficients in the expansion are computed in exact rational arithmetic using the symbolic manipulation system MACSYMA and using a FORTRAN program. The series is analyzed using Pade approximants. The convergence of the series for the maximum amplitude of the limit cycle is limited by two pair of complex conjugate singularities in the complex epsilon-plane. A new expansion parameter is introduced which maps these singularities to infinity and leads to a new expansion for the amplitude which converges for all real values of epsilon. Amplitudes computed from this transformed series agree very well with reported numerical and asymptotic results. For the limit cycle itself, convergence of the series expansion is limited by three pair of complex conjugate branch point singularities. Two pair remain fixed throughout the cycle, and correspond to the singularities found in the maximum amplitude series, while the third pair moves in the epsilon-plane as a function of t from one of the fixed pairs to the other. The limit cycle series is transformed using a new expansion parameter, which leads to a new series that converges for larger values of epsilon.

Femoro-tibial kinematics after TKA in fixed- and mobile-bearing knees in the sagittal plane.

PubMed

Daniilidis, Kiriakos; Höll, Steffen; Gosheger, Georg; Dieckmann, Ralf; Martinelli, Nicolo; Ostermeier, Sven; Tibesku, Carsten O

2013-10-01

Lack of the anterior cruciate ligament in total knee arthroplasty results in paradoxical movement of the femur as opposed to the tibia under deep flexion. Total knee arthroplasty with mobile-bearing inlays has been developed to provide increased physiological movement of the knee joint and to reduce polyethylene abrasion. The aim of this study was to perform an in vitro analysis of the kinematic movement in the sagittal plane in order to show differences between fixed- and mobile-bearing TKA in comparison with the natural knee joint. Seven knee joints of human cadaver material were used in a laboratory experiment. Fixed- and mobile-bearing inlays were tested in sequences under isokinetic extension in so-called kinemator for knee joints, which can simulate muscular traction power by the use of hydraulic cylinders, which crossover the knee joint. As a target parameter, the a.p. translation of the tibio-femoral relative movement was measured in the sagittal plane under ultrasound (Zebris) control. The results show a reduced tibial a.p. translation in relation to the femur in the bearing group compared to the natural joint. In the Z-axis, between 110° and 50° of flexion, linear movement decreases towards caudal movement under extension. Admittedly, the study did not show differences in the movement pattern between "mobile-bearing" and "fixed-bearing" prostheses. Results of this study cannot prove functional advantages of mobile-bearing prostheses for the knee joint kinematic after TKA. Both types of prostheses show typical kinematics of an anterior instability, hence they were incapable of performing physiological movement.

Modified Interior Distance Functions (Theory and Methods)

NASA Technical Reports Server (NTRS)

Polyak, Roman A.

1995-01-01

In this paper we introduced and developed the theory of Modified Interior Distance Functions (MIDF's). The MIDF is a Classical Lagrangian (CL) for a constrained optimization problem which is equivalent to the initial one and can be obtained from the latter by monotone transformation both the objective function and constraints. In contrast to the Interior Distance Functions (IDF's), which played a fundamental role in Interior Point Methods (IPM's), the MIDF's are defined on an extended feasible set and along with center, have two extra tools, which control the computational process: the barrier parameter and the vector of Lagrange multipliers. The extra tools allow to attach to the MEDF's very important properties of Augmented Lagrangeans. One can consider the MIDFs as Interior Augmented Lagrangeans. It makes MIDF's similar in spirit to Modified Barrier Functions (MBF's), although there is a fundamental difference between them both in theory and methods. Based on MIDF's theory, Modified Center Methods (MCM's) have been developed and analyzed. The MCM's find an unconstrained minimizer in primal space and update the Lagrange multipliers, while both the center and the barrier parameter can be fixed or updated at each step. The MCM's convergence was investigated, and their rate of convergence was estimated. The extension of the feasible set and the special role of the Lagrange multipliers allow to develop MCM's, which produce, in case of nondegenerate constrained optimization, a primal and dual sequences that converge to the primal-dual solutions with linear rate, even when both the center and the barrier parameter are fixed. Moreover, every Lagrange multipliers update shrinks the distance to the primal dual solution by a factor 0 less than gamma less than 1 which can be made as small as one wants by choosing a fixed interior point as a 'center' and a fixed but large enough barrier parameter. The numericai realization of MCM leads to the Newton MCM (NMCM). The approximation for the primal minimizer one finds by Newton Method followed by the Lagrange multipliers update. Due to the MCM convergence, when both the center and the barrier parameter are fixed, the condition of the MDF Hessism and the neighborhood of the primal ninimizer where Newton method is 'well' defined remains stable. It contributes to both the complexity and the numerical stability of the NMCM.

Systems and methods for producing hydrocarbons from tar sands formations

DOEpatents

Li, Ruijian [Katy, TX; Karanikas, John Michael [Houston, TX

2009-07-21

A system for treating a tar sands formation is disclosed. A plurality of heaters are located in the formation. The heaters include at least partially horizontal heating sections at least partially in a hydrocarbon layer of the formation. The heating sections are at least partially arranged in a pattern in the hydrocarbon layer. The heaters are configured to provide heat to the hydrocarbon layer. The provided heat creates a plurality of drainage paths for mobilized fluids. At least two of the drainage paths converge. A production well is located to collect and produce mobilized fluids from at least one of the converged drainage paths in the hydrocarbon layer.

Study and Application of Remote Data Moving Transmission under the Network Convergence

NASA Astrophysics Data System (ADS)

Zhiguo, Meng; Du, Zhou

The data transmission is an important problem in remote applications. Advance of network convergence has help to select and use data transmission model. The embedded system and data management platform is a key of the design. With communication module, interface technology and the transceiver which has independent intellectual property rights connected broadband network and mobile network seamlessly. Using the distribution system of mobile base station to realize the wireless transmission, using public networks to implement the data transmission, making the distant information system break through area restrictions and realizing transmission of the moving data, it has been fully recognized in long-distance medical care applications.

Psychometric properties of the mobility inventory for agoraphobia: convergent, discriminant, and criterion-related validity.

PubMed

Chambless, Dianne L; Sharpless, Brian A; Rodriguez, Dianeth; McCarthy, Kevin S; Milrod, Barbara L; Khalsa, Shabad-Ratan; Barber, Jacques P

2011-12-01

Aims of this study were (a) to summarize the psychometric literature on the Mobility Inventory for Agoraphobia (MIA), (b) to examine the convergent and discriminant validity of the MIA's Avoidance Alone and Avoidance Accompanied rating scales relative to clinical severity ratings of anxiety disorders from the Anxiety Disorders Interview Schedule (ADIS), and (c) to establish a cutoff score indicative of interviewers' diagnosis of agoraphobia for the Avoidance Alone scale. A meta-analytic synthesis of 10 published studies yielded positive evidence for internal consistency and convergent and discriminant validity of the scales. Participants in the present study were 129 people with a diagnosis of panic disorder. Internal consistency was excellent for this sample, α=.95 for AAC and .96 for AAL. When the MIA scales were correlated with interviewer ratings, evidence for convergent and discriminant validity for AAL was strong (convergent r with agoraphobia severity ratings=.63 vs. discriminant rs of .10-.29 for other anxiety disorders) and more modest but still positive for AAC (.54 vs. .01-.37). Receiver operating curve analysis indicated that the optimal operating point for AAL as an indicator of ADIS agoraphobia diagnosis was 1.61, which yielded sensitivity of .87 and specificity of .73. Copyright © 2011. Published by Elsevier Ltd.

Psychometric Properties of the Mobility Inventory for Agoraphobia: Convergent, Discriminant, and Criterion-Related Validity

PubMed Central

Chambless, Dianne L.; Sharpless, Brian A.; Rodriguez, Dianeth; McCarthy, Kevin S.; Milrod, Barbara L.; Khalsa, Shabad-Ratan; Barber, Jacques P.

2012-01-01

Aims of this study were (a) to summarize the psychometric literature on the Mobility Inventory for Agoraphobia (MIA), (b) to examine the convergent and discriminant validity of the MIA’s Avoidance Alone and Avoidance Accompanied rating scales relative to clinical severity ratings of anxiety disorders from the Anxiety Disorders Interview Schedule (ADIS), and (c) to establish a cutoff score indicative of interviewers’ diagnosis of agoraphobia for the Avoidance Alone scale. A meta-analytic synthesis of 10 published studies yielded positive evidence for internal consistency and convergent and discriminant validity of the scales. Participants in the present study were 129 people with a diagnosis of panic disorder. Internal consistency was excellent for this sample, α = .95 for AAC and .96 for AAL. When the MIA scales were correlated with interviewer ratings, evidence for convergent and discriminant validity for AAL was strong (convergent r with agoraphobia severity ratings = .63 vs. discriminant rs of .10-.29 for other anxiety disorders) and more modest but still positive for AAC (.54 vs. .01-.37). Receiver operating curve analysis indicated that the optimal operating point for AAL as an indicator of ADIS agoraphobia diagnosis was 1.61, which yielded sensitivity of .87 and specificity of .73. PMID:22035997

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-02-01

Call for Papers: Convergence Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to:

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-03-01

Call for Papers: Convergence Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to:

Comparison of High-Flexion Fixed-Bearing and High-Flexion Mobile-Bearing Total Knee Arthroplasties-A Prospective Randomized Study.

PubMed

Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik

2018-01-01

There is none, to our knowledge, about comparison of high-flexion fixed-bearing and high-flexion mobile-bearing total knee arthroplasties (TKAs) in the same patients. The purpose of this study was to determine whether clinical results; radiographic and computed tomographic scan results; and the survival rate of a high-flexion mobile-bearing TKA is better than that of a high-flexion fixed-bearing TKA. The present study consisted of 92 patients (184 knees) who underwent same-day bilateral TKA. Of those, 17 were men and 75 were women. The mean age at the time of index arthroplasty was 61.5 ± 8.3 years (range 52-65 years). The mean body mass index was 26.2 ± 3.3 kg/m 2 (range 23-34 kg/m 2 ). The mean follow-up was 11.2 years (range 10-12 years). The Knee Society knee scores (93 vs 92 points; P = .531) and function scores (80 vs 80 points; P = 1.000), WOMAC scores (14 vs 15 points; P = .972), and UCLA activity scores (6 vs 6 points; P = 1.000) were not different between the 2 groups at 12 years follow-up. There were no differences in any radiographic and CT scan parameters between the 2 groups. Kaplan-Meier survivorship of the TKA component was 98% (95% confidence interval, 93-100) in the high-flexion fixed-bearing TKA group and 99% (95% confidence interval, 94-100) in the high-flexion mobile-bearing TKA group 12 years after the operation. We found no benefit to mobile-bearing TKA in terms of pain, function, radiographic and CT scan results, and survivorship. Longer-term follow-up is necessary to prove the benefit of the high-flexion mobile-bearing TKA over the high-flexion fixed-bearing TKA. Copyright © 2017 Elsevier Inc. All rights reserved.

Constraints on Subduction Zone Coupling along the Philippine and Manila Trenches based on GPS and Seismological Data

NASA Astrophysics Data System (ADS)

Hamburger, M. W.; Johnson, K. M.; Nowicki, M. A. E.; Bacolcol, T. C.; Solidum, R., Jr.; Galgana, G.; Hsu, Y. J.; Yu, S. B.; Rau, R. J.; McCaffrey, R.

2014-12-01

We present results of two techniques to estimate the degree of coupling along the two major subduction zone boundaries that bound the Philippine Mobile Belt, the Philippine Trench and the Manila Trench. Convergence along these plate margins accommodates about 100 mm/yr of oblique plate motion between the Philippine Sea and Sundaland plates. The coupling estimates are based on a recently acquired set of geodetic data from a dense nationwide network of continuous and campaign GPS sites in the Philippines. First, we use a kinematic, elastic block model (tdefnode; McCaffrey, 2009) that combines existing fault geometries, GPS velocities and focal mechanism solutions to solve for block rotations, fault coupling, and intra-block deformation. Secondly, we use a plate-block kinematic model described in Johnson (2013) to simultaneously estimate long-term fault slip rates, block motions and interseismic coupling on block-bounding faults. The best-fit model represents the Philippine Mobile Belt by 14 independently moving rigid tectonic blocks, separated by active faults and subduction zones. The model predicts rapid convergence along the Manila Trench, decreasing progressively southwards, from > 100 mm/yr in the north to less than 20 mm/yr in the south at the Mindoro Island collision zone. Persistent areas of high coupling, interpreted to be asperities, are observed along the Manila Trench slab interface, in central Luzon (16-18°N) and near its southern and northern terminations. Along the Philippine Trench, we observe ~50 mm/yr of oblique convergence, with high coupling observed at its central and southern segments. We identify the range of allowable coupling distributions and corresponding moment accumulation rates on the two subduction zones by conducting a suite of inversions in which the total moment accumulation rate on a selected fault is fixed. In these constrained moment inversions we test the range of possible solutions that meet criteria for minimum, best-fit, and maximum coupling that still fit the data, based on reduced chi-squared calculations. In spite of the variable coupling, the total potential moment accumulation rate along each of the two subduction zones is estimated to range from 3.98 x 1019 to 2.24 x 1020 N-m yr-1, equivalent to a magnitude Mw 8.4 to 8.9 earthquake per 100 years.

Kinematic comparison between mobile-bearing and fixed-bearing inserts in NexGen legacy posterior stabilized flex total knee arthroplasty.

PubMed

Shi, Kenrin; Hayashida, Kenji; Umeda, Naoya; Yamamoto, Kengo; Kawai, Hideo

2008-02-01

Femoral component rollback and tibial rotation were evaluated using lateral radiographs taken during passive knee flexion under fluoroscopy in NexGen Legacy Posterior Stabilized Flex (Zimmer, Warsaw, Ind) total knee arthroplasties (TKAs; 30 with mobile insert and 26 with fixed insert). Measured maximal flexion angle demonstrated no significant differences. Femoral component rollback was observed predominantly in TKAs with fixed insert in more than 45 degrees flexion and correlated with maximal flexion angle in each group. Tibial internal rotation was more significant in TKAs with mobile insert in maximal flexion. However, tibial internal rotation from 90 degrees to maximal flexion, which demonstrated correlation with maximal flexion angle in each group, did not show significant difference. The kinematic differences between 2 inserts seemed to have little relevance to the maximal flexion angle.

Leader–follower fixed-time consensus of multi-agent systems with high-order integrator dynamics

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

Tian, Bailing; Zuo, Zongyu; Wang, Hong

The leader-follower fixed-time consensus of high-order multi-agent systems with external disturbances is investigated in this paper. A novel sliding manifold is designed to ensure that the tracking errors converge to zero in a fixed-time during the sliding motion. Then, a distributed control law is designed based on Lyapunov technique to drive the system states to the sliding manifold in finite-time independent of initial conditions. Finally, the efficiency of the proposed method is illustrated by numerical simulations.

The Impact of the Rate and Variety of Uses of Fixed and Mobile Broadband on the Progress of CPE: A Chartered Accountant's Perspective

ERIC Educational Resources Information Center

Rawashdeh, Awni; Al-namlah, Lamia

2015-01-01

To examine the impact of the usage of fixed and mobile broadband on the progress of continuing professional education (CPE) from the perspective of chartered accountants in Saudi Arabia, an e-mail survey was conducted. A random sampling of chartered accountants in Saudi Arabia was investigated. This research was aimed to identify any correlation…

75 FR 40833 - Sunshine Act Meeting; Open Commission Meeting; Thursday, July 15, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-14

... OFFICE OF TITLE: Fixed and ENGINEERING AND Mobile services TECHNOLOGY, in the Mobile WIRELESS TELE... investment in the 2 GHz, Big LEO, and L-bands of the Mobile Satellite Service. 3 WIRELINE TITLE: Electronic...

Hydrodynamic interaction of two particles in confined linear shear flow at finite Reynolds number

NASA Astrophysics Data System (ADS)

Yan, Yiguang; Morris, Jeffrey F.; Koplik, Joel

2007-11-01

We discuss the hydrodynamic interactions of two solid bodies placed in linear shear flow between parallel plane walls in a periodic geometry at finite Reynolds number. The computations are based on the lattice Boltzmann method for particulate flow, validated here by comparison to previous results for a single particle. Most of our results pertain to cylinders in two dimensions but some examples are given for spheres in three dimensions. Either one mobile and one fixed particle or else two mobile particles are studied. The motion of a mobile particle is qualitatively similar in both cases at early times, exhibiting either trajectory reversal or bypass, depending upon the initial vector separation of the pair. At longer times, if a mobile particle does not approach a periodic image of the second, its trajectory tends to a stable limit point on the symmetry axis. The effect of interactions with periodic images is to produce nonconstant asymptotic long-time trajectories. For one free particle interacting with a fixed second particle within the unit cell, the free particle may either move to a fixed point or take up a limit cycle. Pairs of mobile particles starting from symmetric initial conditions are shown to asymptotically reach either fixed points, or mirror image limit cycles within the unit cell, or to bypass one another (and periodic images) indefinitely on a streamwise periodic trajectory. The limit cycle possibility requires finite Reynolds number and arises as a consequence of streamwise periodicity when the system length is sufficiently short.

Universities and Libraries Move to the Mobile Web

ERIC Educational Resources Information Center

Aldrich, Alan W.

2010-01-01

The convergence of web-enabled smartphones, the applications designed for smartphone interfaces, and cloud computing is rapidly changing how people interact with each other and with their environments. The commercial sector has taken the lead in creating mobile websites that leverage the capacities of smartphones, and the academic community has…

Fourier-domain Mobility Spectrum Analysis (FMSA) for Characterizing Semiconductors with Multi-Electron/Hole Species

NASA Astrophysics Data System (ADS)

Cui, Boya; Kielb, Edward; Luo, Jiajun; Tang, Yang; Grayson, Matthew

Superlattices and narrow gap semiconductors often host multiple conducting species, such as electrons and holes, requiring a mobility spectral analysis (MSA) method to separate contributions to the conductivity. Here, a least-squares MSA method is introduced: the QR-algorithm Fourier-domain MSA (FMSA). Like other MSA methods, the FMSA sorts the conductivity contributions of different carrier species from magnetotransport measurements, arriving at a best fit to the experimentally measured longitudinal and Hall conductivities σxx and σxy, respectively. This method distinguishes itself from other methods by using the so-called QR-algorithm of linear algebra to achieve rapid convergence of the mobility spectrum as the solution to an eigenvalue problem, and by alternately solving this problem in both the mobility domain and its Fourier reciprocal-space. The result accurately fits a mobility range spanning nearly four orders of magnitude (μ = 300 to 1,000,000 cm2/V .s). This method resolves the mobility spectra as well as, or better than, competing MSA methods while also achieving high computational efficiency, requiring less than 30 second on average to converge to a solution on a standard desktop computer. Acknowledgement: Funded by AFOSR FA9550-15-1-0377 and AFOSR FA9550-15-1-0247.

Multi-sectorial convergence in greenhouse gas emissions.

PubMed

Oliveira, Guilherme de; Bourscheidt, Deise Maria

2017-07-01

This paper uses the World Input-Output Database (WIOD) to test the hypothesis of per capita convergence in greenhouse gas (GHG) emissions for a multi-sectorial panel of countries. The empirical strategy applies conventional estimators of random and fixed effects and Arellano and Bond's (1991) GMM to the main pollutants related to the greenhouse effect. For reasonable empirical specifications, the model revealed robust evidence of per capita convergence in CH 4 emissions in the agriculture, food, and services sectors. The evidence of convergence in CO 2 emissions was moderate in the following sectors: agriculture, food, non-durable goods manufacturing, and services. In all cases, the time for convergence was less than 15 years. Regarding emissions by energy use, the largest source of global warming, there was only moderate evidence in the extractive industry sector-all other pollutants presented little or no evidence. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Microcomputer-Based Network Optimization Package.

DTIC Science & Technology

1981-09-01

from either cases a or c as Truncated-Newton directions. It can be shown [Ref. 27] that the TNCG algorithm is globally convergent and capable of...nonzero values of LGB indicate bounds at which arcs are fixed or reversed. Fixed arcs have negative T ( ) while free arcs have positive T ( ) values...Solution of Generalized Network Problems," Working Paper, Department of Finance and Business Economics , School of Business , University of Southern

Fixed points of contractive mappings in b-metric-like spaces.

PubMed

Hussain, Nawab; Roshan, Jamal Rezaei; Parvaneh, Vahid; Kadelburg, Zoran

2014-01-01

We discuss topological structure of b-metric-like spaces and demonstrate a fundamental lemma for the convergence of sequences. As an application we prove certain fixed point results in the setup of such spaces for different types of contractive mappings. Finally, some periodic point results in b-metric-like spaces are obtained. Two examples are presented in order to verify the effectiveness and applicability of our main results.

Efficient self-consistent viscous-inviscid solutions for unsteady transonic flow

NASA Technical Reports Server (NTRS)

Howlett, J. T.

1985-01-01

An improved method is presented for coupling a boundary layer code with an unsteady inviscid transonic computer code in a quasi-steady fashion. At each fixed time step, the boundary layer and inviscid equations are successively solved until the process converges. An explicit coupling of the equations is described which greatly accelerates the convergence process. Computer times for converged viscous-inviscid solutions are about 1.8 times the comparable inviscid values. Comparison of the results obtained with experimental data on three airfoils are presented. These comparisons demonstrate that the explicitly coupled viscous-inviscid solutions can provide efficient predictions of pressure distributions and lift for unsteady two-dimensional transonic flows.

Efficient self-consistent viscous-inviscid solutions for unsteady transonic flow

NASA Technical Reports Server (NTRS)

Howlett, J. T.

1985-01-01

An improved method is presented for coupling a boundary layer code with an unsteady inviscid transonic computer code in a quasi-steady fashion. At each fixed time step, the boundary layer and inviscid equations are successively solved until the process converges. An explicit coupling of the equations is described which greatly accelerates the convergence process. Computer times for converged viscous-inviscid solutions are about 1.8 times the comparable inviscid values. Comparison of the results obtained with experimental data on three airfoils are presented. These comparisons demonstrate that the explicitly coupled viscous-inviscid solutions can provide efficient predictions of pressure distributions and lift for unsteady two-dimensional transonic flow.

Convergence Time towards Periodic Orbits in Discrete Dynamical Systems

PubMed Central

San Martín, Jesús; Porter, Mason A.

2014-01-01

We investigate the convergence towards periodic orbits in discrete dynamical systems. We examine the probability that a randomly chosen point converges to a particular neighborhood of a periodic orbit in a fixed number of iterations, and we use linearized equations to examine the evolution near that neighborhood. The underlying idea is that points of stable periodic orbit are associated with intervals. We state and prove a theorem that details what regions of phase space are mapped into these intervals (once they are known) and how many iterations are required to get there. We also construct algorithms that allow our theoretical results to be implemented successfully in practice. PMID:24736594

Fixing convergence of Gaussian belief propagation

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

Johnson, Jason K; Bickson, Danny; Dolev, Danny

Gaussian belief propagation (GaBP) is an iterative message-passing algorithm for inference in Gaussian graphical models. It is known that when GaBP converges it converges to the correct MAP estimate of the Gaussian random vector and simple sufficient conditions for its convergence have been established. In this paper we develop a double-loop algorithm for forcing convergence of GaBP. Our method computes the correct MAP estimate even in cases where standard GaBP would not have converged. We further extend this construction to compute least-squares solutions of over-constrained linear systems. We believe that our construction has numerous applications, since the GaBP algorithm ismore » linked to solution of linear systems of equations, which is a fundamental problem in computer science and engineering. As a case study, we discuss the linear detection problem. We show that using our new construction, we are able to force convergence of Montanari's linear detection algorithm, in cases where it would originally fail. As a consequence, we are able to increase significantly the number of users that can transmit concurrently.« less

Soil N retention and nitrate leaching in three types of dunes in the Mu Us desert of China.

PubMed

Jin, Zhao; Zhu, Yajuan; Li, Xiangru; Dong, Yunshe; An, Zhisheng

2015-09-15

A large reservoir of soil nitrate in desert subsoil zones has been demonstrated in previous studies; however, information on the subsoil nitrate reservoir and its distribution characteristics in the deserts of China is still limited. This study investigated the distribution patterns of soil total nitrogen (N), nitrate, ammonium, and stable isotopic ratios of (15)N (δ(15)N) in shallow (1 m) and subsoil (5 m) profiles in three types of dunes in the Mu Us desert of China. We found that soil N retention of the fixed and semi-fixed dunes followed a progressive nutrient depletion pattern in shallow soil profiles, whereas the subsoil nitrate of the fixed, semi-fixed and mobile dunes maintained a conservative accumulation pattern. The results indicate that the subsoil of the Mu Us desert may act as a reservoir of available nitrate. Furthermore, a soil δ(15)N analysis indicate that the nitrate content of the fixed dune is likely derived from soil nitrification, whereas the nitrate content in the mobile dune is derived from atmospheric nitrate deposition. Within the context of looming climate change and intensifying human activities, the subsoil nitrate content in the deserts of northern China could become mobilized and increase environmental risks to groundwater.

Evolving a Puncture Black Hole with Fixed Mesh Refinement

NASA Technical Reports Server (NTRS)

Imbiriba, Breno; Baker, John; Choi, Dae-II; Centrella, Joan; Fiske. David R.; Brown, J. David; vanMeter, James R.; Olson, Kevin

2004-01-01

We present a detailed study of the effects of mesh refinement boundaries on the convergence and stability of simulations of black hole spacetimes. We find no technical problems. In our applications of this technique to the evolution of puncture initial data, we demonstrate that it is possible to simulaneously maintain second order convergence near the puncture and extend the outer boundary beyond 100M, thereby approaching the asymptotically flat region in which boundary condition problems are less difficult.

A Comparison of Mobile and Fixed Device Access on User Engagement Associated With Women, Infants, and Children (WIC) Online Nutrition Education

PubMed Central

2016-01-01

Background Online health education has expanded its reach due to cost-effective implementation and demonstrated effectiveness. However, a limitation exists with the evaluation of online health education implementations and how the impact of the system is attenuated by the extent to which a user engages with it. Moreover, the current online health education research does not consider how this engagement has been affected by the transition from fixed to mobile user access over the last decade. Objective This paper focuses on comparing the impact mobile versus fixed devices have on user engagement key performance indicators (KPI) associated with the wichealth website (.org), an Internet-based parent-child feeding intervention offered to clients associated with the US Department of Agriculture’s Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Methods Data were collected from 612,201 nutrition education lessons completed by 305,735 unique WIC participants in 21 states over a 1-year period. Data consisted of system-collected measures, profile items, and items from an exit survey administered at the conclusion of each lesson. User engagement was defined based on 3 KPIs associated with usage of the wichealth website: number of link views, link view time, and progression in stage of readiness to change. Independent samples t tests were used to compare KPIs between fixed only and mobile only device users and paired samples t tests were used to compare KPIs within users who completed at least one lesson each on both a fixed and mobile device. A logistic regression was performed to estimate the odds of KPI performance thresholds in the independent samples study group given access device type while controlling for confounding of user characteristics associated with these KPIs. Results Analysis of 8 user characteristics (lessons completed, race, ethnicity, language, state of residence, pregnancy status, beginning stage of change, and preferred nutrition education method) were significantly (P<.001) related to various KPI differences between mobile and fixed device access. Non-mobile users were significantly (P<.001) more likely to engage based on all 3 KPIs, even after logistic regression control for the potential confounding related to the strongly associated user characteristics identified. Conclusions The findings of this study support the idea that online health education developers need to seriously consider access device when creating programs. Online health education developers need to take extra effort to truly understand access patterns of populations being served, and whether or not access device will influence user engagement performance indicators. PMID:27847351

A comparative analysis between fixed bearing total knee arthroplasty (PFC Sigma) and rotating platform total knee arthroplasty (PFC-RP) with minimum 3-year follow-up.

PubMed

Jawed, Akram; Kumar, Vijay; Malhotra, R; Yadav, C S; Bhan, S

2012-06-01

Since the introduction of mobile bearing total knee designs nearly 30 years back, many studies have been done to evaluate its long-term result. Comparison with fixed bearing designs has been done in the past, but the studies were confounded by variables such as disease, surgeon, bone quality, pain tolerance, etc. We attempt to eliminate these variables in this study. A total of 50 patients who had bilateral arthritis of the knee with similar deformity and pre-operative range of motion on both sides agreed to have one knee replaced with mobile bearing total knee design (PFC-RP) and the other with a fixed bearing design (PFC Sigma) were prospectively evaluated. Comparative analysis of both the designs was done at a mean follow-up of 40 months, minimizing patient, surgeon and observer related bias. Clinical and radiographic outcome, survival and complication rates were compared. At a mean follow-up of 40 months (range 36-47 months), no benefit of mobile bearing (PFC-RP) over fixed bearing design (PFC Sigma) could be demonstrated with respect to Knee Society scores, pain scores, range of flexion, subject preference or patello-femoral complication rates. Radiographs showed no difference in prosthetic alignment. No patient required a revision surgery till last follow-up. Our study demonstrated no advantage of the mobile-bearing arthroplasty over fixed bearing arthroplasty with regard to clinical results at short-term follow-up. However, longer follow-up is necessary to confirm whether these results are sustained.

The cultural effects of job mobility and the belief in a fixed world: evidence from performance forecast.

PubMed

Chen, Jing; Chiu, Chi-yue; Chan, S Fiona

2009-11-01

Results from 5 studies illustrate how perception of and experiences with low job mobility can shape culture-characteristic pattern of judgments and behaviors. Although both Americans and some Asian groups (e.g., Chinese, Asian Americans) consider having successful practitioners' personality traits (role personalities) to be important to job performance, the Asian groups place heavier emphasis on possessing role personalities when making performance forecast than do Americans (Studies 1-3). Moreover, even among Americans, a brief subjective experience with low job mobility can increase the perceived importance of possessing role personalities in performance forecast (Study 4), and a brief direct experience with low job mobility can increase job applicants' tendency to claim possession of role personality traits in job applications (Study 5). Furthermore, the belief in a fixed world mediates the relationship between perception of low job mobility and perceived importance of possessing role personalities in performance forecast (Study 2).

Using Mobile Monitoring to Assess Spatial Variability in Urban Air Pollution Levels: Opportunities and Challenges (Invited)

NASA Astrophysics Data System (ADS)

Larson, T.

2010-12-01

Measuring air pollution concentrations from a moving platform is not a new idea. Historically, however, most information on the spatial variability of air pollutants have been derived from fixed site networks operating simultaneously over space. While this approach has obvious advantages from a regulatory perspective, with the increasing need to understand ever finer scales of spatial variability in urban pollution levels, the use of mobile monitoring to supplement fixed site networks has received increasing attention. Here we present examples of the use of this approach: 1) to assess existing fixed-site fine particle networks in Seattle, WA, including the establishment of new fixed-site monitoring locations; 2) to assess the effectiveness of a regulatory intervention, a wood stove burning ban, on the reduction of fine particle levels in the greater Puget Sound region; and 3) to assess spatial variability of both wood smoke and mobile source impacts in both Vancouver, B.C. and Tacoma, WA. Deducing spatial information from the inherently spatio-temporal measurements taken from a mobile platform is an area that deserves further attention. We discuss the use of “fuzzy” points to address the fine-scale spatio-temporal variability in the concentration of mobile source pollutants, specifically to deduce the broader distribution and sources of fine particle soot in the summer in Vancouver, B.C. We also discuss the use of principal component analysis to assess the spatial variability in multivariate, source-related features deduced from simultaneous measurements of light scattering, light absorption and particle-bound PAHs in Tacoma, WA. With increasing miniaturization and decreasing power requirements of air monitoring instruments, the number of simultaneous measurements that can easily be made from a mobile platform is rapidly increasing. Hopefully the methods used to design mobile monitoring experiments for differing purposes, and the methods used to interpret those measurements will keep pace.

Treating childhood pneumonia in hard-to-reach areas: a model-based comparison of mobile clinics and community-based care.

PubMed

Pitt, Catherine; Roberts, Bayard; Checchi, Francesco

2012-01-10

Where hard-to-access populations (such as those living in insecure areas) lack access to basic health services, relief agencies, donors, and ministries of health face a dilemma in selecting the most effective intervention strategy. This paper uses a decision mathematical model to estimate the relative effectiveness of two alternative strategies, mobile clinics and fixed community-based health services, for antibiotic treatment of childhood pneumonia, the world's leading cause of child mortality. A "Markov cycle tree" cohort model was developed in Excel with Visual Basic to compare the number of deaths from pneumonia in children aged 1 to 59 months expected under three scenarios: 1) No curative services available, 2) Curative services provided by a highly-skilled but intermittent mobile clinic, and 3) Curative services provided by a low-skilled community health post. Parameter values were informed by literature and expert interviews. Probabilistic sensitivity analyses were conducted for several plausible scenarios. We estimated median pneumonia-specific under-5 mortality rates of 0.51 (95% credible interval: 0.49 to 0.541) deaths per 10,000 child-days without treatment, 0.45 (95% CI: 0.43 to 0.48) with weekly mobile clinics, and 0.31 (95% CI: 0.29 to 0.32) with CHWs in fixed health posts. Sensitivity analyses found the fixed strategy superior, except when mobile clinics visited communities daily, where rates of care-seeking were substantially higher at mobile clinics than fixed posts, or where several variables simultaneously differed substantially from our baseline assumptions. Current evidence does not support the hypothesis that mobile clinics are more effective than CHWs. A CHW strategy therefore warrants consideration in high-mortality, hard-to-access areas. Uncertainty remains, and parameter values may vary across contexts, but the model allows preliminary findings to be updated as new or context-specific evidence becomes available. Decision analytic modelling can guide needed field-based research efforts in hard-to-access areas and offer evidence-based insights for decision-makers.

Mobilization of beryllium in the sedimentary column at convergent margins

USGS Publications Warehouse

You, C.-F.; Morris, J.D.; Gieskes, J.M.; Rosenbauer, R.; Zheng, S.H.; Xu, X.; Ku, T.-L.; Bischoff, J.L.

1994-01-01

Studies of Be distributions in subduction zone sediments will help to understand questions regarding the enrichments of cosmogenic Be-10 in arc volcanic rocks. Analyses of Be-10 and Be-9 in sediments of Ocean Drilling Program Site 808, Nankai Trough and Be-9 in porewaters of Site 808 and Sites 671 and 672, Barbados ridge complex, show significant decreases in solid phase Be-10 and large increases of porewater Be-9 at the location of the de??collement zone and below or at potential flow conduits. These data imply the potential mobilization of Be during pore fluid expulsion upon sediment burial. Experiments involving reaction between a de??collement sediment and a synthetic NaCl-CaCl2 solution at elevated pressure and temperatures were conducted in an attempt to mimic early subduction zone processes. The results demonstrate that Be is mobilized under elevated pressure and temperature with a strong pH dependence. The Be mobilization provides an explanation of Be-10 enrichment in arc volcanic rocks and supports the argument of the importance of the fluid processes in subduction zones at convergent margins. ?? 1994.

Bandwidth management for mobile mode of mobile monitoring system for Indonesian Volcano

NASA Astrophysics Data System (ADS)

Evita, Maria; Djamal, Mitra; Zimanowski, Bernd; Schilling, Klaus

2017-01-01

Volcano monitoring requires the system which has high-fidelity operation and real-time acquisition. MONICA (Mobile Monitoring System for Indonesian Volcano), a system based on Wireless Sensor Network, mobile robot and satellite technology has been proposed to fulfill this requirement for volcano monitoring system in Indonesia. This system consists of fixed-mode for normal condition and mobile mode for emergency situation. The first and second modes have been simulated in slow motion earthquake cases of Merapi Volcano, Indonesia. In this research, we have investigated the application of our bandwidth management for high-fidelity operation and real time acquisition in mobile mode of a strong motion earthquake from this volcano. The simulation result showed that our system still could manage the bandwidth even when there were 2 died fixed node after had stroked by the lightning. This result (64% to 83% throughput in average) was still better than the bandwidth utilized by the existing equipment (0% throughput because of the broken seismometer).

The United States mobile satellite service

NASA Astrophysics Data System (ADS)

Kiesling, J. D.

1986-09-01

The proposed U.S. mobile satellite service provides services to America's nonurban land mass where terrestrial mobile systems find little application. Based on state of the art satellite technology, and use of omnidirectional, steered, and fixed antennas, a broad range of services at affordable prices will be available, including land mobile, service to intra coastal waterways, and aviation.

Delay-Aware Energy-Efficient Routing towards a Path-Fixed Mobile Sink in Industrial Wireless Sensor Networks.

PubMed

Wu, Shaobo; Chou, Wusheng; Niu, Jianwei; Guizani, Mohsen

2018-03-18

Wireless sensor networks (WSNs) involve more mobile elements with their widespread development in industries. Exploiting mobility present in WSNs for data collection can effectively improve the network performance. However, when the sink (i.e., data collector) path is fixed and the movement is uncontrollable, existing schemes fail to guarantee delay requirements while achieving high energy efficiency. This paper proposes a delay-aware energy-efficient routing algorithm for WSNs with a path-fixed mobile sink, named DERM, which can strike a desirable balance between the delivery latency and energy conservation. We characterize the object of DERM as realizing the energy-optimal anycast to time-varying destination regions, and introduce a location-based forwarding technique tailored for this problem. To reduce the control overhead, a lightweight sink location calibration method is devised, which cooperates with the rough estimation based on the mobility pattern to determine the sink location. We also design a fault-tolerant mechanism called track routing to tackle location errors for ensuring reliable and on-time data delivery. We comprehensively evaluate DERM by comparing it with two canonical routing schemes and a baseline solution presented in this work. Extensive evaluation results demonstrate that DERM can provide considerable energy savings while meeting the delay constraint and maintaining a high delivery ratio.

Delay-Aware Energy-Efficient Routing towards a Path-Fixed Mobile Sink in Industrial Wireless Sensor Networks

PubMed Central

Wu, Shaobo; Chou, Wusheng; Niu, Jianwei; Guizani, Mohsen

2018-01-01

Wireless sensor networks (WSNs) involve more mobile elements with their widespread development in industries. Exploiting mobility present in WSNs for data collection can effectively improve the network performance. However, when the sink (i.e., data collector) path is fixed and the movement is uncontrollable, existing schemes fail to guarantee delay requirements while achieving high energy efficiency. This paper proposes a delay-aware energy-efficient routing algorithm for WSNs with a path-fixed mobile sink, named DERM, which can strike a desirable balance between the delivery latency and energy conservation. We characterize the object of DERM as realizing the energy-optimal anycast to time-varying destination regions, and introduce a location-based forwarding technique tailored for this problem. To reduce the control overhead, a lightweight sink location calibration method is devised, which cooperates with the rough estimation based on the mobility pattern to determine the sink location. We also design a fault-tolerant mechanism called track routing to tackle location errors for ensuring reliable and on-time data delivery. We comprehensively evaluate DERM by comparing it with two canonical routing schemes and a baseline solution presented in this work. Extensive evaluation results demonstrate that DERM can provide considerable energy savings while meeting the delay constraint and maintaining a high delivery ratio. PMID:29562628

Strong coupling strategy for fluid-structure interaction problems in supersonic regime via fixed point iteration

NASA Astrophysics Data System (ADS)

Storti, Mario A.; Nigro, Norberto M.; Paz, Rodrigo R.; Dalcín, Lisandro D.

2009-03-01

In this paper some results on the convergence of the Gauss-Seidel iteration when solving fluid/structure interaction problems with strong coupling via fixed point iteration are presented. The flow-induced vibration of a flat plate aligned with the flow direction at supersonic Mach number is studied. The precision of different predictor schemes and the influence of the partitioned strong coupling on stability is discussed.

Fixed Points of Contractive Mappings in b-Metric-Like Spaces

PubMed Central

Hussain, Nawab; Roshan, Jamal Rezaei

2014-01-01

We discuss topological structure of b-metric-like spaces and demonstrate a fundamental lemma for the convergence of sequences. As an application we prove certain fixed point results in the setup of such spaces for different types of contractive mappings. Finally, some periodic point results in b-metric-like spaces are obtained. Two examples are presented in order to verify the effectiveness and applicability of our main results. PMID:25143980

47 CFR 95.29 - Channels available.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SERVICES General Mobile Radio Service (GMRS) § 95.29 Channels available. (a) For a base station, fixed station, mobile station, or repeater station (a GMRS station that simultaneously retransmits the... non-individual, a mobile station or a small base station operating in the simplex mode may transmit on...

47 CFR 90.469 - Unattended operation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MOBILE RADIO SERVICES Transmitter Control § 90.469 Unattended operation. (a) Subject to the provisions of §§ 90.243, 90.245, and 90.247, mobile relay, fixed relay, and mobile repeater stations are authorized... where they are activated by either electrical or mechanical devices, provided the licensee adopts...

Assessing the costs of mobile voluntary counseling and testing at the work place versus facility based voluntary counseling and testing in Namibia.

PubMed

de Beer, Ingrid; Chani, Kudakwashe; Feeley, Frank G; Rinke de Wit, Tobias F; Sweeney-Bindels, Els; Mulongeni, Pancho

2015-01-01

Bophelo! is a mobile voluntary counseling and testing (VCT) and wellness screening program operated by PharmAccess at workplaces in Namibia, funded from both public and private resources. Publicly funded fixed site New Start centers provide similar services in Namibia. At this time of this study, no comparative information on the cost effectiveness of mobile versus fixed site service provision was available in Namibia to inform future programming for scale-up of VCT. The objectives of the study were to assess the costs of mobile VCT and wellness service delivery in Namibia and to compare the costs and effectiveness with fixed site VCT testing in Namibia. The full direct costs of all resources used by the mobile and fixed site testing programs and data on people tested and outcomes were obtained from PharmAccess and New Start centers in Namibia. Data were also collected on the source of funding, both public donor funding and private funding through contributions from employers. The data were analyzed using Microsoft Excel to determine the average cost per person tested for HIV. In 2009, the average cost per person tested for HIV at the Bophelo! mobile clinic was an estimated US$60.59 (US$310,451 for the 5124 people tested). Private employer contributions to the testing costs reduced the public cost per person tested to US$37.76. The incremental cost per person associated with testing for conditions other than HIV infection was US$11.35, an increase of 18.7%, consisting of the costs of additional tests (US$8.62) and staff time (US$2.73). The cost of testing one person for HIV in 2009 at the New Start centers was estimated at US$58.21 (US$4,082,936 for the 70 143 people tested). Mobile clinics can provide cost-effective wellness testing services at the workplace and have the potential to mobilize local private funding sources. Providing wellness testing in addition to VCT can help address the growing issue of non-communicable diseases.

Variable input observer for structural health monitoring of high-rate systems

NASA Astrophysics Data System (ADS)

Hong, Jonathan; Laflamme, Simon; Cao, Liang; Dodson, Jacob

2017-02-01

The development of high-rate structural health monitoring methods is intended to provide damage detection on timescales of 10 µs -10ms where speed of detection is critical to maintain structural integrity. Here, a novel Variable Input Observer (VIO) coupled with an adaptive observer is proposed as a potential solution for complex high-rate problems. The VIO is designed to adapt its input space based on real-time identification of the system's essential dynamics. By selecting appropriate time-delayed coordinates defined by both a time delay and an embedding dimension, the proper input space is chosen which allows more accurate estimations of the current state and a reduction of the convergence rate. The optimal time-delay is estimated based on mutual information, and the embedding dimension is based on false nearest neighbors. A simulation of the VIO is conducted on a two degree-of-freedom system with simulated damage. Results are compared with an adaptive Luenberger observer, a fixed time-delay observer, and a Kalman Filter. Under its preliminary design, the VIO converges significantly faster than the Luenberger and fixed observer. It performed similarly to the Kalman Filter in terms of convergence, but with greater accuracy.

Eigensolutions of nonviscously damped systems based on the fixed-point iteration

NASA Astrophysics Data System (ADS)

Lázaro, Mario

2018-03-01

In this paper, nonviscous, nonproportional, symmetric vibrating structures are considered. Nonviscously damped systems present dissipative forces depending on the time history of the response via kernel hereditary functions. Solutions of the free motion equation leads to a nonlinear eigenvalue problem involving mass, stiffness and damping matrices, this latter as dependent on frequency. Viscous damping can be considered as a particular case, involving damping forces as function of the instantaneous velocity of the degrees of freedom. In this work, a new numerical procedure to compute eigensolutions is proposed. The method is based on the construction of certain recursive functions which, under a iterative scheme, allow to reach eigenvalues and eigenvectors simultaneously and avoiding computation of eigensensitivities. Eigenvalues can be read then as fixed-points of those functions. A deep analysis of the convergence is carried out, focusing specially on relating the convergence conditions and error-decay rate to the damping model features, such as the nonproportionality and the viscoelasticity. The method is validated using two 6 degrees of freedom numerical examples involving both nonviscous and viscous damping and a continuous system with a local nonviscous damper. The convergence and the sequences behavior are in agreement with the results foreseen by the theory.

Aerothermodynamics and Propulsion Integration for Hypersonic Vehicles (L’Integration de la Propusion et de l’aerodynnamique pour les vehicules hypersoniques).

DTIC Science & Technology

1996-10-01

aerothermoelasticity, temperature gradients and internal heat gies, belong fully resuable SSTO and TSTO sytems, protection. The demand of extreme light...supersonic conditions, convergent and convergent-divergent nozzles matching the cold cage internal diameter will be fixed on the end plate. A set of five...in hypersonic flow. AIAA Paper93- des Fluides, Avril 1996. 5111, 5th International Aerospace Planes and 16. Morrisette, E.L., Creel, T.R., Chen, F.J

Enabling Electric Propulsion for Flight

NASA Technical Reports Server (NTRS)

Ginn, Starr Renee

2015-01-01

Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

Material flows of mobile phones and accessories in Nigeria: Environmental implications and sound end-of-life management options

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

Osibanjo, Oladele; Nnorom, Innocent Chidi

Presently, Nigeria is one of the fastest growing Telecom markets in the world. The country's teledensity increased from a mere 0.4 in 1999 to 10 in 2005 following the liberalization of the Telecom sector in 2001. More than 25 million new digital mobile lines have been connected by June 2006. Large quantities of mobile phones and accessories including secondhand and remanufactured products are being imported to meet the pent-up demand. This improvement in mobile telecom services resulted in the preference of mobile telecom services to fixed lines. Consequently, the contribution of fixed lines decreased from about 95% in year 2000more » to less than 10% in March 2005. This phenomenal progress in information technology has resulted in the generation of large quantities of electronic waste (e-waste) in the country. Abandoned fixed line telephone sets estimated at 120,000 units are either disposed or stockpiled. Increasing quantities of waste mobile phones estimated at 8 million units by 2007, and accessories will be generated. With no material recovery facility for e-waste and/or appropriate solid waste management infrastructure in place, these waste materials end up in open dumps and unlined landfills. These practices create the potential for the release of toxic metals and halocarbons from batteries, printed wiring boards, liquid crystal display and plastic housing units. This paper presents an overview of the developments in the Nigerian Telecom sector, the material in-flow of mobile phones, and the implications of the management practices for wastes from the Telecom sector in the country.« less

CCC calculated differential cross sections of electron-H2 scattering

NASA Astrophysics Data System (ADS)

Fursa, Dmitry; Zammit, Mark; Savage, Jeremy; Bray, Igor

2016-09-01

Recently we applied the molecular convergent close-coupling (CCC) method to electron scattering from molecular hydrogen H2. Convergence of the major differential cross sections has been explicitly demonstrated in the fixed-nuclei approximation. A large close-coupling expansion that coupled highly excited states and ionization channels proved to be important to obtain convergent results. Here we present benchmark elastic and electronic excitation differential cross sections for b3Σu+ , a3Σg+ , c3Πu , B1Σu+ , EF1Σg+ , C1Πu , and e3Σu+ states and compare with available experiment and previous calculations. Work supported by Los Alamos National Laboratory and Curtin University.

Learning with Mobiles in Developing Countries: Technology, Language, and Literacy

ERIC Educational Resources Information Center

Traxler, John M.

2017-01-01

In the countries of the global South, the challenges of fixed infrastructure and environment, the apparent universality of mobile hardware, software and network technologies and the rhetoric of the global knowledge economy have slowed or impoverished the development of appropriate theoretical discourses to underpin learning with mobiles. This…

Technological Readiness of UiTM Students in Using Mobile Phones in the English Language Classroom

ERIC Educational Resources Information Center

Murugan, Agelyia; Sai, George Teoh Boon; Lin, Agnes Liau Wei

2017-01-01

Mobile Assisted Language Learning (MALL) by using devices such as mobile phones is an ideal learning platform for learners to acquire language and share knowledge beyond the confines of a fixed location. By utilizing the mobile applications available via smartphone, learners can engage in collaborative networks and find information in a variety of…

The total occlusal convergence of the abutment of a partial fixed dental prosthesis: A definition and a clinical technique for its assessment

PubMed Central

Mamoun, John S.

2013-01-01

The abutment(s) of a partial fixed dental prosthesis (PFDP) should have a minimal total occlusal convergence (TOC), also called a taper, in order to ensure adequate retention of a PFDP that will be made for the abutment(s), given the height of the abutment(s). This article reviews the concept of PFDP abutment TOC and presents an alternative definition of what TOC is, defining it as the extent to which the shape of an abutment differs from an ideal cylinder shape of an abutment. This article also reviews experimental results concerning what is the ideal TOC in degrees and explores clinical techniques of estimating the TOC of a crown abutment. The author suggests that Dentists use high magnification loupes (×6-8 magnification or greater) or a surgical operating microscope when preparing crown abutments, to facilitate creating a minimum abutment TOC. PMID:24932130

Experimental evaluation of expendable supersonic nozzle concepts

NASA Technical Reports Server (NTRS)

Baker, V.; Kwon, O.; Vittal, B.; Berrier, B.; Re, R.

1990-01-01

Exhaust nozzles for expendable supersonic turbojet engine missile propulsion systems are required to be simple, short and compact, in addition to having good broad-range thrust-minus-drag performance. A series of convergent-divergent nozzle scale model configurations were designed and wind tunnel tested for a wide range of free stream Mach numbers and nozzle pressure ratios. The models included fixed geometry and simple variable exit area concepts. The experimental and analytical results show that the fixed geometry configurations tested have inferior off-design thrust-minus-drag performance in the transonic Mach range. A simple variable exit area configuration called the Axi-Quad nozzle, combining features of both axisymmetric and two-dimensional convergent-divergent nozzles, performed well over a broad range of operating conditions. Analytical predictions of the flow pattern as well as overall performance of the nozzles, using a fully viscous, compressible CFD code, compared very well with the test data.

The theory of maximally and minimally even sets, the one- dimensional antiferromagnetic Ising model, and the continued fraction compromise of musical scales

NASA Astrophysics Data System (ADS)

Douthett, Elwood (Jack) Moser, Jr.

1999-10-01

Cyclic configurations of white and black sites, together with convex (concave) functions used to weight path length, are investigated. The weights of the white set and black set are the sums of the weights of the paths connecting the white sites and black sites, respectively, and the weight between sets is the sum of the weights of the paths that connect sites opposite in color. It is shown that when the weights of all configurations of a fixed number of white and a fixed number of black sites are compared, minimum (maximum) weight of a white set, minimum (maximum) weight of the a black set, and maximum (minimum) weight between sets occur simultaneously. Such configurations are called maximally even configurations. Similarly, the configurations whose weights are the opposite extremes occur simultaneously and are called minimally even configurations. Algorithms that generate these configurations are constructed and applied to the one- dimensional antiferromagnetic spin-1/2 Ising model. Next the goodness of continued fractions as applied to musical intervals (frequency ratios and their base 2 logarithms) is explored. It is shown that, for the intermediate convergents between two consecutive principal convergents of an irrational number, the first half of the intermediate convergents are poorer approximations than the preceding principal convergent while the second half are better approximations; the goodness of a middle intermediate convergent can only be determined by calculation. These convergents are used to determine what equal-tempered systems have intervals that most closely approximate the musical fifth (pn/ qn = log2(3/2)). The goodness of exponentiated convergents ( 2pn/qn~3/2 ) is also investigated. It is shown that, with the exception of a middle convergent, the goodness of the exponential form agrees with that of its logarithmic Counterpart As in the case of the logarithmic form, the goodness of a middle intermediate convergent in the exponential form can only be determined by calculation. A Desirability Function is constructed that simultaneously measures how well multiple intervals fit in a given equal-tempered system. These measurements are made for octave (base 2) and tritave systems (base 3). Combinatorial properties important to music modulation are considered. These considerations lead These considerations lead to the construction of maximally even scales as partitions of an equal-tempered system.

Loopback Radio Frequency Translator For The Acts Mobile Terminal

NASA Technical Reports Server (NTRS)

Davis, John F.

1993-01-01

This paper summarizes the system design and performance measurements of the Loopback Translator, a satellite simulator to be used in testing the fixed and mobile terminal hardware prior to the ACTS launch.

Wheeled mobility device transportation safety in fixed route and demand-responsive public transit vehicles within the United States.

PubMed

Frost, Karen L; van Roosmalen, Linda; Bertocci, Gina; Cross, Douglas J

2012-01-01

An overview of the current status of wheelchair transportation safety in fixed route and demand-responsive, non-rail, public transportation vehicles within the US is presented. A description of each mode of transportation is provided, followed by a discussion of the primary issues affecting safety, accessibility, and usability. Technologies such as lifts, ramps, securement systems, and occupant restraint systems, along with regulations and voluntary industry standards have been implemented with the intent of improving safety and accessibility for individuals who travel while seated in their wheeled mobility device (e.g., wheelchair or scooter). However, across both fixed route and demand-responsive transit systems a myriad of factors such as nonuse and misuse of safety systems, oversized wheeled mobility devices, vehicle space constraints, and inadequate vehicle operator training may place wheeled mobility device (WhMD) users at risk of injury even under non-impact driving conditions. Since WhMD-related incidents also often occur during the boarding and alighting process, the frequency of these events, along with factors associated with these events are described for each transit mode. Recommendations for improving WhMD transportation are discussed given the current state of

Lagrangian Modeling of Evaporating Sprays at Diesel Engine Conditions: Effects of Multi-Hole Injector Nozzles With JP-8 Surrogates

DTIC Science & Technology

2014-05-01

solver to treat the spray process. An Adaptive Mesh Refinement (AMR) and fixed embedding technique is employed to capture the gas - liquid interface with...Adaptive Mesh Refinement (AMR) and fixed embedding technique is employed to capture the gas - liquid interface with high fidelity while keeping the cell...in single and multi-hole nozzle configurations. The models were added to the present CONVERGE liquid fuel database and validated extensively

Risk management policies and practices regarding radio frequency electromagnetic fields: results from a WHO survey.

PubMed

Dhungel, Amit; Zmirou-Navier, Denis; van Deventer, Emilie

2015-04-01

This study aims to describe current risk management practices and policies across the world in relation to personal exposures from devices emitting radiofrequency fields, environmental exposures from fixed installations and exposures in the work environment. Data from 86 countries representing all WHO regions were collected through a survey. The majority of countries (76.8 %) had set exposure limits for mobile devices, almost all (90.7 %) had set public exposure limits for fixed installations and 76.5 % had specified exposure limits for personnel in occupational settings. A number of other policies had been implemented at the national level, ranging from information provisions on how to reduce personal exposures and restrictions of usage for certain populations, such as children or pregnant women to prevention of access around base stations. This study suggests that countries with higher mobile subscriptions tend to have set radiofrequency exposure limits for mobile devices and to have provisions on exposure measurements about fixed installations. © The Author 2014. Published by Oxford University Press.

[Study on schistosomiasis control measures in mobile boat fishermen. III. Construction and application of regional joint mechanism for schistosomiasis examination and treatment in boatmen].

PubMed

Yang, Gao; Le-Ping, Sun; Yin-Ping, Zuo; Yu-Hui, Xu; Zheng-Qiu, Zhang; Yu-Cai, Ma; Jin-Bin, Gao; Xi-Guang, Zhu; Bo, Zheng; Guo-Jing, Yang; Qing-Biao, Hong; Kun, Yang; You-Sheng, Liang

2011-10-01

To construct the regional joint mechanism for schistosomiasis examination and treatment and the examination protocol among mobile boatmen, so as to provide effective measures for control of mobile infectious sources of schistosomiasis in the Yangtze River basin. According to the characteristics of the cargo frequent mobility of ships with fixed anchor points, the health, maritime and transport sections were jointly cooperated to set up sites for schistosomiasis examination and treatment in ship locks, wharfs and harbors. The infection of schistosomiasis was detected by means of rapid immunological screening and stool examination, and the regional joint mechanism was constructed. The sero-positives were traced for further parasitological examinations and treatment by using the regional joint network for schistosomiasis examination and treatment. The schistosome infections in boatmen were analyzed and compared between different examination and treatment sites and among different navigation coverage. A total of 16 sites for examination and treatment of schistosomiasis, including 5 fixed sites and 11 mobile sites, were set up in 12 townships of 6 districts (counties) of Yangzhou City. During a period between June and August, the examination of schistosomiasis was conducted in 40 sites, and of the 1 225 boatmen from 967 boats detected, 19 cases were sero-positive, with a positive rate of 1.55%. Among the 14 sero-positives examined, no stool positive patients were found. Among the 1 225 boatmen detected, 820 were from fixed sites and 405 from mobile sites, and 4 and 15 cases were found, respectively, with positive rates of 0.49% and 3.70%, respectively, and the sero-positive rate was higher in mobile sites and that in fixed sites. A total of 898 boatmen from the Yangtze River basin and 305 from the local inland rivers were examined, and 3 and 16 sero-positive cases were detected, respectively, with positive rates of 0.33% and 5.25%, respectively, and the sero-positive rate was significantly higher in the boatmen from the local inland rivers than that from the Yangtze River basin. Regional joint mechanism is an effective strategy for examination and treatment of schistosomiasis among mobile boatmen, which provides a new approach to control mobile infectious sources of schistosomiasis in the Yangtze River basin.

Tightly Coupled Integration of GPS Ambiguity Fixed Precise Point Positioning and MEMS-INS through a Troposphere-Constrained Adaptive Kalman Filter

PubMed Central

Han, Houzeng; Xu, Tianhe; Wang, Jian

2016-01-01

Precise Point Positioning (PPP) makes use of the undifferenced pseudorange and carrier phase measurements with ionospheric-free (IF) combinations to achieve centimeter-level positioning accuracy. Conventionally, the IF ambiguities are estimated as float values. To improve the PPP positioning accuracy and shorten the convergence time, the integer phase clock model with between-satellites single-difference (BSSD) operation is used to recover the integer property. However, the continuity and availability of stand-alone PPP is largely restricted by the observation environment. The positioning performance will be significantly degraded when GPS operates under challenging environments, if less than five satellites are present. A commonly used approach is integrating a low cost inertial sensor to improve the positioning performance and robustness. In this study, a tightly coupled (TC) algorithm is implemented by integrating PPP with inertial navigation system (INS) using an Extended Kalman filter (EKF). The navigation states, inertial sensor errors and GPS error states are estimated together. The troposphere constrained approach, which utilizes external tropospheric delay as virtual observation, is applied to further improve the ambiguity-fixed height positioning accuracy, and an improved adaptive filtering strategy is implemented to improve the covariance modelling considering the realistic noise effect. A field vehicular test with a geodetic GPS receiver and a low cost inertial sensor was conducted to validate the improvement on positioning performance with the proposed approach. The results show that the positioning accuracy has been improved with inertial aiding. Centimeter-level positioning accuracy is achievable during the test, and the PPP/INS TC integration achieves a fast re-convergence after signal outages. For troposphere constrained solutions, a significant improvement for the height component has been obtained. The overall positioning accuracies of the height component are improved by 30.36%, 16.95% and 24.07% for three different convergence times, i.e., 60, 50 and 30 min, respectively. It shows that the ambiguity-fixed horizontal positioning accuracy has been significantly improved. When compared with the conventional PPP solution, it can be seen that position accuracies are improved by 19.51%, 61.11% and 23.53% for the north, east and height components, respectively, after one hour convergence through the troposphere constraint fixed PPP/INS with adaptive covariance model. PMID:27399721

Convergence of methods for coupling of microscopic and mesoscopic reaction-diffusion simulations

NASA Astrophysics Data System (ADS)

Flegg, Mark B.; Hellander, Stefan; Erban, Radek

2015-05-01

In this paper, three multiscale methods for coupling of mesoscopic (compartment-based) and microscopic (molecular-based) stochastic reaction-diffusion simulations are investigated. Two of the three methods that will be discussed in detail have been previously reported in the literature; the two-regime method (TRM) and the compartment-placement method (CPM). The third method that is introduced and analysed in this paper is called the ghost cell method (GCM), since it works by constructing a "ghost cell" in which molecules can disappear and jump into the compartment-based simulation. Presented is a comparison of sources of error. The convergent properties of this error are studied as the time step Δt (for updating the molecular-based part of the model) approaches zero. It is found that the error behaviour depends on another fundamental computational parameter h, the compartment size in the mesoscopic part of the model. Two important limiting cases, which appear in applications, are considered: Δt → 0 and h is fixed; Δt → 0 and h → 0 such that √{ Δt } / h is fixed. The error for previously developed approaches (the TRM and CPM) converges to zero only in the limiting case (ii), but not in case (i). It is shown that the error of the GCM converges in the limiting case (i). Thus the GCM is superior to previous coupling techniques if the mesoscopic description is much coarser than the microscopic part of the model.

Migration Opportunities

NASA Astrophysics Data System (ADS)

Grasselli, Agnese; Vangelista, Alessandro; Bolli, Stefano

Main Players in ICT arena, especially those with multiple assets such as fixed and mobile networks are evolving towards innovative services that leverage on a particular asset's specificity (e.g. mobility, bandwidth, location …) but assure a seamless user experience .

Electromagnetic Fields and Public Health: Mobile Phones

MedlinePlus

... Ebola virus disease » Home / News / Fact sheets / Detail Electromagnetic fields and public health: mobile phones 8 October ... fixed antennas called base stations. Radiofrequency waves are electromagnetic fields, and unlike ionizing radiation such as X- ...

A Comparison of Mobile and Fixed Device Access on User Engagement Associated With Women, Infants, and Children (WIC) Online Nutrition Education.

PubMed

Brusk, John J; Bensley, Robert J

2016-11-15

Online health education has expanded its reach due to cost-effective implementation and demonstrated effectiveness. However, a limitation exists with the evaluation of online health education implementations and how the impact of the system is attenuated by the extent to which a user engages with it. Moreover, the current online health education research does not consider how this engagement has been affected by the transition from fixed to mobile user access over the last decade. This paper focuses on comparing the impact mobile versus fixed devices have on user engagement key performance indicators (KPI) associated with the wichealth website (.org), an Internet-based parent-child feeding intervention offered to clients associated with the US Department of Agriculture's Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Data were collected from 612,201 nutrition education lessons completed by 305,735 unique WIC participants in 21 states over a 1-year period. Data consisted of system-collected measures, profile items, and items from an exit survey administered at the conclusion of each lesson. User engagement was defined based on 3 KPIs associated with usage of the wichealth website: number of link views, link view time, and progression in stage of readiness to change. Independent samples t tests were used to compare KPIs between fixed only and mobile only device users and paired samples t tests were used to compare KPIs within users who completed at least one lesson each on both a fixed and mobile device. A logistic regression was performed to estimate the odds of KPI performance thresholds in the independent samples study group given access device type while controlling for confounding of user characteristics associated with these KPIs. Analysis of 8 user characteristics (lessons completed, race, ethnicity, language, state of residence, pregnancy status, beginning stage of change, and preferred nutrition education method) were significantly (P<.001) related to various KPI differences between mobile and fixed device access. Non-mobile users were significantly (P<.001) more likely to engage based on all 3 KPIs, even after logistic regression control for the potential confounding related to the strongly associated user characteristics identified. The findings of this study support the idea that online health education developers need to seriously consider access device when creating programs. Online health education developers need to take extra effort to truly understand access patterns of populations being served, and whether or not access device will influence user engagement performance indicators. ©John J Brusk, Robert J Bensley. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 15.11.2016.

Student Transience in North Carolina: The Effect of School Mobility on Student Outcomes Using Longitudinal Data. Working Paper 22

ERIC Educational Resources Information Center

Xu, Zeyu; Hannaway, Jane; D'Souza, Stephanie

2009-01-01

This paper describes the school mobility rates for elementary and middle school students in North Carolina and attempts to estimate the effect of school mobility on the performance of different groups of students using student fixed effects models. School mobility is defined as changing schools at times that are non-promotional (e.g., moving…

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-08-01

Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to: Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks Integration strategies for multiservice transport platforms Access methods that bridge traditional and emerging services Network signaling and control methodologies All-optical packet routing and switching techniques

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-06-01

Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to: Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks Integration strategies for multiservice transport platforms Access methods that bridge traditional and emerging services Network signaling and control methodologies All-optical packet routing and switching techniques

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-05-01

Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to: Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks Integration strategies for multiservice transport platforms Access methods that bridge traditional and emerging services Network signaling and control methodologies All-optical packet routing and switching techniques

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-04-01

Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to: Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks Integration strategies for multiservice transport platforms Access methods that bridge traditional and emerging services Network signaling and control methodologies All-optical packet routing and switching techniques

[Atraumatic dislocation in mobile-bearing total knee arthroplasty: two case reports].

PubMed

Schuh, A; Hönle, W

2007-10-01

Atraumatic dislocation following total knee arthroplasty (TKA) is a rare condition. Severe complications after dislocation are lesion of the vascular-nerve bundle, compartment syndrome or amputation. The benefit of TKA with mobile-bearing are an improvement of the range of motion and better articulation. In comparison to fixed-bearing TKA there is the risk of dislocation or breakage of the polyethylene insert. We present two cases with dislocation following TKA with mobile-bearing. In both cases preoperatively there was a significant weakening of the function of the quadriceps muscle. During revision of the TKA severe damage with multiple scratches of the polyethylene onlay could be detected. The damage of the PE onlay could especially be found at the tibial aspect. Follow-up showed an uneventful course after conversion to fixed-bearing polyethylen component. In cases of dislocation following TKA with mobile-bearing operative revision is recommended to exchange the damaged PE onlay and prevent increased wear. TKA with mobile-bearing should be reserved only for cases with a good quadriceps muscle function.

Online Kiosks: The Alternative to Mobile Technologies for Mobile Users.

ERIC Educational Resources Information Center

Slack, Frances; Rowley, Jennifer

2002-01-01

Describes the development and use of online kiosks in contexts where users are away from fixed technologies. Uses a case study of a United Kingdom airport terminal to illustrate different types of kiosk applications; makes comparisons with mobile phone technologies; and considers their role in self-managed, self-service delivery of information and…

Mobile Router Testing with Diverse RF Communications Links

NASA Technical Reports Server (NTRS)

Brooks, David; Hoder, Doug; Wilkins, Ryan

2004-01-01

This is a short report on demonstrations using Mobile IP and several diverse physical communications links to connect a mobile network to a fixed IPv4 internet. The first section is a description of the equipment used, followed by descriptions of the tests, the theoretical results, and finally conclusions and the actual data.

Making mLearning Work: Utilizing Mobile Technology for Active Exploration, Collaboration, Assessment, and Reflection in Higher Education

ERIC Educational Resources Information Center

Fisher, Mercedes; Baird, Derek E.

2007-01-01

The convergence of mobile technologies into student-centered learning environments requires academic institutions to design new and more effective learning, teaching, and user experience strategies. In this article we share results from an mLearning design experiment and analysis from a student survey conducted at the National College of Ireland.…

Mobile Math: Math Educators and Students Engage in Mobile Learning

ERIC Educational Resources Information Center

Franklin, Teresa; Peng, Li-Wei

2008-01-01

The public and educational communities are aware of the continuing crisis in math education in our middle schools and the convergence of technologies for teaching and learning. This paper presents a case study in which iPod Touch[R] was used to help middle school students learn about algebraic equations and, in particular, the concept of slope,…

47 CFR 22.1031 - Temporary fixed stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

....1031 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon... days before the end of the six month period. (b) International communications. Communications between...

5G: The Convergence of Wireless Communications.

PubMed

Chávez-Santiago, Raúl; Szydełko, Michał; Kliks, Adrian; Foukalas, Fotis; Haddad, Yoram; Nolan, Keith E; Kelly, Mark Y; Masonta, Moshe T; Balasingham, Ilangko

As the rollout of 4G mobile communication networks takes place, representatives of industry and academia have started to look into the technological developments toward the next generation (5G). Several research projects involving key international mobile network operators, infrastructure manufacturers, and academic institutions, have been launched recently to set the technological foundations of 5G. However, the architecture of future 5G systems, their performance, and mobile services to be provided have not been clearly defined. In this paper, we put forth the vision for 5G as the convergence of evolved versions of current cellular networks with other complementary radio access technologies. Therefore, 5G may not be a single radio access interface but rather a "network of networks". Evidently, the seamless integration of a variety of air interfaces, protocols, and frequency bands, requires paradigm shifts in the way networks cooperate and complement each other to deliver data rates of several Gigabits per second with end-to-end latency of a few milliseconds. We provide an overview of the key radio technologies that will play a key role in the realization of this vision for the next generation of mobile communication networks. We also introduce some of the research challenges that need to be addressed.

Electrophoretic mobilities of erythrocytes in various buffers

NASA Technical Reports Server (NTRS)

Plank, L. D.; Kunze, M. E.; Todd, P. W.

1985-01-01

The calibration of space flight equipment depends on a source of standard test particles, this test particle of choice is the fixed erythrocyte. Erythrocytes from different species have different electrophoretic mobilities. Electrophoretic mobility depends upon zeta potential, which, in turn depends upon ionic strength. Zeta potential decreases with increasing ionic strength, so cells have high electrophoretic mobility in space electrophoresis buffers than in typical physiological buffers. The electrophoretic mobilities of fixed human, rat, and rabbit erythrocytes in 0.145 M salt and buffers of varying ionic strength, temperature, and composition, to assess the effects of some of the unique combinations used in space buffers were characterized. Several effects were assessed: glycerol or DMSO (dimethylsulfoxide) were considered for use as cryoprotectants. The effect of these substances on erythrocyte electrophoretic mobility was examined. The choice of buffer depended upon cell mobility. Primary experiments with kidney cells established the choice of buffer and cryoprotectant. A nonstandard temperature of EPM in the suitable buffer was determined. A loss of ionic strength control occurs in the course of preparing columns for flight, the effects of small increases in ionic strength over the expected low values need to be evaluated.

Mobile Disdrometer Observations of Nocturnal Mesoscale Convective Systems During PECAN

NASA Astrophysics Data System (ADS)

Bodine, D. J.; Rasmussen, K. L.

2015-12-01

Understanding microphysical processes in nocturnal mesoscale convective systems (MCSs) is an important objective of the Plains Elevated Convection At Night (PECAN) experiment, which occurred from 1 June - 15 July 2015 in the central Great Plains region of the United States. Observations of MCSs were collected using a large array of mobile and fixed instrumentation, including ground-based radars, soundings, PECAN Integrated Sounding Arrays (PISAs), and aircraft. In addition to these observations, three mobile Parsivel disdrometers were deployed to obtain drop-size distribution (DSD) measurements to further explore microphysical processes in convective and stratiform regions of nocturnal MCSs. Disdrometers were deployed within close range of a multiple frequency network of mobile and fixed dual-polarization radars (5 - 30 km range), and near mobile sounding units and PISAs. Using mobile disdrometer and multiple-wavelength, dual-polarization radar data, microphysical properties of convective and stratiform regions of MCSs are investigated. The analysis will also examine coordinated Range-Height Indicator (RHI) scans over the disdrometers to elucidate vertical DSD structure. Analysis of dense observations obtained during PECAN in combination with mobile disdrometer DSD measurements contributes to a greater understanding of the structural characteristics and evolution of nocturnal MCSs.

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

Austin, Anthony P.; Trefethen, Lloyd N.

The trigonometric interpolants to a periodic function f in equispaced points converge if f is Dini-continuous, and the associated quadrature formula, the trapezoidal rule, converges if f is continuous. What if the points are perturbed? With equispaced grid spacing h, let each point be perturbed by an arbitrary amount <= alpha h, where alpha is an element of[0, 1/2) is a fixed constant. The Kadec 1/4 theorem of sampling theory suggests there may be trouble for alpha >= 1/4. We show that convergence of both the interpolants and the quadrature estimates is guaranteed for all alpha < 1/2 if fmore » is twice continuously differentiable, with the convergence rate depending on the smoothness of f. More precisely, it is enough for f to have 4 alpha derivatives in a certain sense, and we conjecture that 2 alpha derivatives are enough. Connections with the Fejer-Kalmar theorem are discussed.« less

Mobile Communication Via Satellite

NASA Technical Reports Server (NTRS)

Yan, Tsun-Yee; Naderi, Firouz M.

1988-01-01

System mixes real-time and delayed-transmission channels. Combination of L-band and SHF links connect fixed and mobile equipment on ground to satellite relay. Software and hardware architecture conforms structure of open-system-interconnection model suggested by International Standards Organization.

The digital divide: Trends in global mobile and broadband Internet access from 2000–2010

PubMed Central

Ronquillo, Charlene; Currie, Leanne

2012-01-01

The digital divide is described as the gap between those who do and do not have access to digital information and communications technologies (ICT). ICTs are viewed as an indicator of infrastructure and potential for development, and are a growing platform for health information and services delivery. This study compares the penetration of mobile and broadband Internet technologies by global region from 2000 to 2010. Results illustrate the rapid growth of mobile cellular telephone subscriptions in all global regions with trends suggesting a continued increase. Little to modest gains were made in fixed broadband Internet subscriptions globally. There is a growing popularity of mobile subscriptions with use of data communications, exceeding the numbers of fixed Internet subscriptions. This comparison reveals current strengths that can be built on and highlights the importance of awareness of global trends and using such knowledge to inform design and delivery of ICT-based health services. PMID:24199118

Cooperative path following control of multiple nonholonomic mobile robots.

PubMed

Cao, Ke-Cai; Jiang, Bin; Yue, Dong

2017-11-01

Cooperative path following control problem of multiple nonholonomic mobile robots has been considered in this paper. Based on the framework of decomposition, the cooperative path following problem has been transformed into path following problem and cooperative control problem; Then cascaded theory of non-autonomous system has been employed in the design of controllers without resorting to feedback linearization. One time-varying coordinate transformation based on dilation has been introduced to solve the uncontrollable problem of nonholonomic robots when the whole group's reference converges to stationary point. Cooperative path following controllers for nonholonomic robots have been proposed under persistent reference or reference target that converges to stationary point respectively. Simulation results using Matlab have illustrated the effectiveness of the obtained theoretical results. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

47 CFR 90.7 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... A regularly interacting group of base, mobile and associated control and fixed relay stations... qualify as unrestricted. Control point. Any place from which a transmitter's functions may be controlled. Control station. An Operational Fixed Station, the transmissions of which are used to control...

47 CFR 90.7 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... A regularly interacting group of base, mobile and associated control and fixed relay stations... qualify as unrestricted. Control point. Any place from which a transmitter's functions may be controlled. Control station. An Operational Fixed Station, the transmissions of which are used to control...

Making an implant-level impression using solid plastic, press-fit, closed-tray impression copings: a clinical report.

PubMed

Selecman, Audrey M; Wicks, Russell A

2009-03-01

An implant-level impression is often desired for designing and fabricating an implant-supported fixed restoration, especially when 2 or more implants have been placed. However, convergent implants placed too close in proximity pose several problems, starting with the impression. In situations of extreme convergence or close proximity, modification of conventional metal copings may be impossible. This clinical report describes the use and associated advantages and disadvantages of solid plastic, press-fit, closed-tray impression copings as a mechanism suitable to create an implant-level cast.

Enabling Electric Propulsion for Flight

NASA Technical Reports Server (NTRS)

Ginn, Starr

2014-01-01

Description of current ARMD projects; Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project (new ARMD reorg), sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

Convergence of quantum electrodynamics in a curved modification of Minkowski space.

PubMed Central

Segal, I E; Zhou, Z

1994-01-01

The interaction and total hamiltonians for quantum electrodynamics, in the interaction representation, are entirely regular self-adjoint operators in Hilbert space, in the universal covering manifold M of the conformal compactification of Minkowski space Mo. (M is conformally equivalent to the Einstein universe E, in which Mo may be canonically imbedded.) In a fixed Lorentz frame this may be expressed as convergence in a spherical space with suitable periodic boundary conditions in time. The traditional relativistic theory is the formal limit of the present variant as the space curvature vanishes. PMID:11607455

Fixed-Time Outer Synchronization of Complex Networks with Noise Coupling

NASA Astrophysics Data System (ADS)

Shi, Hong-Jun; Miao, Lian-Ying; Sun, Yong-Zheng; Liu, Mao-Xing

2018-03-01

In this paper, the fixed-time outer synchronization of complex networks with noise coupling is investigated. Based on the theory of fixed-time stability and matrix inequalities, sufficient conditions for fixed-time outer synchronization are established and the estimation of the upper bound of the setting time is obtained. The result shows that the setting time can be adjusted to a desired value regardless of the initial states. Numerical simulations are performed to verify the effectiveness of the theoretical results. The effects of control parameters and the density of controlled nodes on the converging time are studied. Supported by the National Natural Science Foundation of China under Grant Nos. 11711530203 and 11771443, and the Fundamental Research Funds for the Central Universities under Grant No. 2015XKMS076

Are There Differences in Gait Mechanics in Patients With A Fixed Versus Mobile Bearing Total Ankle Arthroplasty? A Randomized Trial.

PubMed

Queen, Robin M; Franck, Christopher T; Schmitt, Daniel; Adams, Samuel B

2017-10-01

Total ankle arthroplasty (TAA) is an alternative to arthrodesis, but no randomized trial has examined whether a fixed bearing or mobile bearing implant provides improved gait mechanics. We wished to determine if fixed- or mobile-bearing TAA results in a larger improvement in pain scores and gait mechanics from before surgery to 1 year after surgery, and to quantify differences in outcomes using statistical analysis and report the standardized effect sizes for such comparisons. Patients with end-stage ankle arthritis who were scheduled for TAA between November 2011 and June 2013 (n = 40; 16 men, 24 women; average age, 63 years; age range, 35-81 years) were prospectively recruited for this study from a single foot and ankle orthopaedic clinic. During this period, 185 patients underwent TAA, with 144 being eligible to participate in this study. Patients were eligible to participate if they were able to meet all study inclusion criteria, which were: no previous diagnosis of rheumatoid arthritis, a contralateral TAA, bilateral ankle arthritis, previous revision TAA, an ankle fusion revision, or able to walk without the use of an assistive device, weight less than 250 pounds (114 kg), a sagittal or coronal plane deformity less than 15°, no presence of avascular necrosis of the distal tibia, no current neuropathy, age older than 35 years, no history of a talar neck fracture, or an avascular talus. Of the 144 eligible patients, 40 consented to participate in our randomized trial. These 40 patients were randomly assigned to either the fixed (n = 20) or mobile bearing implant group (n = 20). Walking speed, bilateral peak dorsiflexion angle, peak plantar flexion angle, sagittal plane ankle ROM, peak ankle inversion angle, peak plantar flexion moment, peak plantar flexion power during stance, peak weight acceptance, and propulsive vertical ground reaction force were analyzed during seven self-selected speed level walking trials for 33 participants using an eight-camera motion analysis system and four force plates. Seven patients were not included in the analysis owing to cancelled surgery (one from each group) and five were lost to followup (four with fixed bearing and one with mobile bearing implants). A series of effect-size calculations and two-sample t-tests comparing postoperative and preoperative increases in outcome variables between implant types were used to determine the differences in the magnitude of improvement between the two patient cohorts from before surgery to 1 year after surgery. The sample size in this study enabled us to detect a standardized shift of 1.01 SDs between group means with 80% power and a type I error rate of 5% for all outcome variables in the study. This randomized trial did not reveal any differences in outcomes between the two implant types under study at the sample size collected. In addition to these results, effect size analysis suggests that changes in outcome differ between implant types by less than 1 SD. Detection of the largest change score or observed effect (propulsive vertical ground reaction force [Fixed: 0.1 ± 0.1; 0.0-1.0; Mobile: 0.0 ± 0.1; 0.0-0.0; p = 0.0.051]) in this study would require a future trial to enroll 66 patients. However, the smallest change score or observed effect (walking speed [Fixed: 0.2 ± 0.3; 0.1-0.4; Mobile: 0.2 ± 0.3; 0.0-0.3; p = 0.742]) requires a sample size of 2336 to detect a significant difference with 80% power at the observed effect sizes. To our knowledge, this is the first randomized study to report the observed effect size comparing improvements in outcome measures between fixed and mobile bearing implant types. This study was statistically powered to detect large effects and descriptively analyze observed effect sizes. Based on our results there were no statistically or clinically meaningful differences between the fixed and mobile bearing implants when examining gait mechanics and pain 1 year after TAA. Level II, therapeutic study.

Unmanned Air Vehicle -Version 1.0

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

Fred Oppel, SNL 06134

2013-04-17

This package contains modules that model the mobility of systems such as helicopters and fixed wing flying in the air. This package currently models first order physics - basically a velocity integrator. UAV mobility uses an internal clock to maintain stable, high-fidelity simulations over large time steps This package depends on interface that reside in the Mobility package.

Commercial Technology at the Tactical Edge

DTIC Science & Technology

2013-06-01

Typical environmental examples are survivability in the face of hostile action, lack of fixed infrastructure , high mobility and ruggedness...Disconnected, Intermittent, and Limited (DIL) Communications Delay Tolerance Mobile Ad Hoc Networks (MANETs) Loss of infrastructure Security Cyber...for Apple’s IOS.25 In particular, various vendors have built application infrastructures around the various mobile phone operating systems (OSs) such

47 CFR 90.733 - Permissible operations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ability to construct and operate its nationwide land mobile system, as required in §§ 90.713 (b), (c) and... paging or fixed systems on a primary basis instead of or in addition to its land mobile operations, it... benchmark for the construction of its land mobile system base stations as prescribed in § 90.725(a); and (2...

Mobile Phones in Africa: How Much Do We Really Know?

ERIC Educational Resources Information Center

James, Jeffrey; Versteeg, Mila

2007-01-01

Mobile phones are a crucial mode of communication and welfare enhancement in poor countries, especially those lacking an infrastructure of fixed lines. In recent years much has been written about how mobile telephony in Africa is rapidly reducing the digital divide with developed countries. Yet, when one examines the evidence it is not at all…

75 FR 49871 - Fixed and Mobile Services in the Mobile Satellite Service

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-16

... on ways to promote innovation and investment throughout the MSS bands while also ensuring market-wide..., utilization, innovation and investment in the spectrum for terrestrial services throughout the 2 GHz, Big LEO... use. [[Page 49874

Experiments for Ka-band mobile applications: The ACTS mobile terminal

NASA Technical Reports Server (NTRS)

Estabrook, Polly; Dessouky, Khaled; Jedrey, Thomas

1990-01-01

To explore the potential of Ka-band to support mobile satellite services, the Jet Propulsion Laboratory (JPL) has initiated the design and development of a Ka-band land-mobile terminal to be used with the Advanced Communications Technology Satellite (ACTS). The planned experimental setup with ACTS is described. Brief functional descriptions of the mobile and fixed terminals are provided. The inputs required from the propagation community to support the design activities and the planned experiments are also discussed.

The role of boundary layer momentum advection in the mean location of the ITCZ

NASA Astrophysics Data System (ADS)

Dixit, Vishal; Srinivasan, J.

2017-08-01

The inter-tropical convergence zones (ITCZ) form closer to the equator during equinoxes while they form well away from the equator during the boreal summer. A simple three-way balance between the pressure gradients, Coriolis force and effective Rayleigh friction has been classically used to diagnose the location of maximum boundary layer convergence in the near equatorial ITCZ. If such a balance can capture the dynamics of off-equatorial convergence was not known. We used idealized aqua planet simulations with fixed, zonally symmetric sea surface temperature boundary conditions to simulate the near equatorial and off-equatorial ITCZ. As opposed to the convergence of inter-hemispheric flows in the near equatorial convergence, the off-equatorial convergence forms due to the deceleration of cross-equatorial meridional flow. The detailed momentum budget of the off-equatorial convergence zone reveals that the simple balance is not sufficient to capture the relevant dynamics. The deceleration of the meridional flow is strongly modulated by the inertial effects due to the meridional advection of zonal momentum in addition to the terms in the simple balance. The simple balance predicts a spurious near equatorial convergence and a consistent off-equatorial convergence of the meridional flow. The spurious convergence disappears when inertial effects are included in the balance. As cross equatorial meridional flow decelerates to form convergence, the inertial effects cancel the pressure gradient effects near the equator while they add away from the equator. The contribution to the off-equatorial convergence induced by the pressure gradients is significantly larger than the contribution due to the inertial effects and hence pressure gradients appear to be the primary factor in anchoring the strength and location of the off-equatorial convergence.

Making Higher Education More European through Student Mobility? Revisiting EU Initiatives in the Context of the Bologna Process

ERIC Educational Resources Information Center

Papatsiba, Vassiliki

2006-01-01

This paper focuses on the analysis of student mobility in the EU as a means to stimulate convergence of diverse higher education systems. The argument is based on official texts and other texts of political communication of the European Commission. The following discussion is placed within the current context of the Bologna process and its aim to…

47 CFR 90.7 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... interacting group of base, mobile and associated control and fixed relay stations intended to provide land... one that does not qualify as unrestricted. Control point. Any place from which a transmitter's functions may be controlled. Control station. An Operational Fixed Station, the transmissions of which are...

47 CFR 90.7 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... interacting group of base, mobile and associated control and fixed relay stations intended to provide land... one that does not qualify as unrestricted. Control point. Any place from which a transmitter's functions may be controlled. Control station. An Operational Fixed Station, the transmissions of which are...

47 CFR 90.7 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... interacting group of base, mobile and associated control and fixed relay stations intended to provide land... one that does not qualify as unrestricted. Control point. Any place from which a transmitter's functions may be controlled. Control station. An Operational Fixed Station, the transmissions of which are...

Concentration of Access to Information and Communication Technologies in the Municipalities of the Brazilian Legal Amazon.

PubMed

de Brito, Silvana Rossy; da Silva, Aleksandra do Socorro; Cruz, Adejard Gaia; Monteiro, Maurílio de Abreu; Vijaykumar, Nandamudi Lankalapalli; da Silva, Marcelino Silva; Costa, João Crisóstomo Weyl Albuquerque; Francês, Carlos Renato Lisboa

2016-01-01

This study fills demand for data on access and use of information and communication technologies (ICT) in the Brazilian legal Amazon, a region of localities with identical economic, political, and social problems. We use the 2010 Brazilian Demographic Census to compile data on urban and rural households (i) with computers and Internet access, (ii) with mobile phones, and (iii) with fixed phones. To compare the concentration of access to ICT in the municipalities of the Brazilian Amazon with other regions of Brazil, we use a concentration index to quantify the concentration of households in the following classes: with computers and Internet access, with mobile phones, with fixed phones, and no access. These data are analyzed along with municipal indicators on income, education, electricity, and population size. The results show that for urban households, the average concentration in the municipalities of the Amazon for computers and Internet access and for fixed phones is lower than in other regions of the country; meanwhile, that for no access and mobile phones is higher than in any other region. For rural households, the average concentration in the municipalities of the Amazon for computers and Internet access, mobile phones, and fixed phones is lower than in any other region of the country; meanwhile, that for no access is higher than in any other region. In addition, the study shows that education and income are determinants of inequality in accessing ICT in Brazilian municipalities and that the existence of electricity in rural households is directly associated with the ownership of ICT resources.

Concentration of Access to Information and Communication Technologies in the Municipalities of the Brazilian Legal Amazon

PubMed Central

de Brito, Silvana Rossy; da Silva, Aleksandra do Socorro; Cruz, Adejard Gaia; Monteiro, Maurílio de Abreu; Vijaykumar, Nandamudi Lankalapalli; da Silva, Marcelino Silva; Costa, João Crisóstomo Weyl Albuquerque; Francês, Carlos Renato Lisboa

2016-01-01

This study fills demand for data on access and use of information and communication technologies (ICT) in the Brazilian legal Amazon, a region of localities with identical economic, political, and social problems. We use the 2010 Brazilian Demographic Census to compile data on urban and rural households (i) with computers and Internet access, (ii) with mobile phones, and (iii) with fixed phones. To compare the concentration of access to ICT in the municipalities of the Brazilian Amazon with other regions of Brazil, we use a concentration index to quantify the concentration of households in the following classes: with computers and Internet access, with mobile phones, with fixed phones, and no access. These data are analyzed along with municipal indicators on income, education, electricity, and population size. The results show that for urban households, the average concentration in the municipalities of the Amazon for computers and Internet access and for fixed phones is lower than in other regions of the country; meanwhile, that for no access and mobile phones is higher than in any other region. For rural households, the average concentration in the municipalities of the Amazon for computers and Internet access, mobile phones, and fixed phones is lower than in any other region of the country; meanwhile, that for no access is higher than in any other region. In addition, the study shows that education and income are determinants of inequality in accessing ICT in Brazilian municipalities and that the existence of electricity in rural households is directly associated with the ownership of ICT resources. PMID:27035577

Enhanced performance of the Westinghouse Series 1000 Mobile Satellite Telephone System

NASA Technical Reports Server (NTRS)

Martinson, Richard E.

1995-01-01

The Westinghouse Series 1000 Mobile Satellite Telephone System is designed for land mobile, maritime, and fixed site land applications. The product currently operates on the Optus Mobilesat system in Australia and will operate on American Mobile Satellite Corporation's (AMSC) Skycell service in the U.S. and TMI Communications' (TMIC) MSAT service in Canada. The architecture allows the same transceiver electronics to be used for diverse mobile applications. Advanced antenna designs have made land mobile satellite communications a reality. This paper details the unique high performance product and its configuration for the vehicle mounted land mobile application.

47 CFR 90.213 - Frequency stability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... range (MHz) Fixed and base stations Mobile stations Over 2 watts output power 2 watts or less output...-930 1.5 935-940 0.1 1.5 1.5 1427-1435 9 300 300 300 Above 2450 10 1 Fixed and base stations with over... stability of 5 ppm. 5 In the 150-174 MHz band, fixed and base stations with a 12.5 kHz channel bandwidth...

Performance analysis of PPP ambiguity resolution with UPD products estimated from different scales of reference station networks

NASA Astrophysics Data System (ADS)

Wang, Siyao; Li, Bofeng; Li, Xingxing; Zang, Nan

2018-01-01

Integer ambiguity fixing with uncalibrated phase delay (UPD) products can significantly shorten the initialization time and improve the accuracy of precise point positioning (PPP). Since the tracking arcs of satellites and the behavior of atmospheric biases can be very different for the reference networks with different scales, the qualities of corresponding UPD products may be also various. The purpose of this paper is to comparatively investigate the influence of different scales of reference station networks on UPD estimation and user ambiguity resolution. Three reference station networks with global, wide-area and local scales are used to compute the UPD products and analyze their impact on the PPP-AR. The time-to-first-fix, the unfix rate and the incorrect fix rate of PPP-AR are analyzed. Moreover, in order to further shorten the convergence time for obtaining precise positioning, a modified partial ambiguity resolution (PAR) and corresponding validation strategy are presented. In this PAR method, the ambiguity subset is determined by removing the ambiguity one by one in the order of ascending elevations. Besides, for static positioning mode, a coordinate validation strategy is employed to enhance the reliability of the fixed coordinate. The experiment results show that UPD products computed by smaller station network are more accurate and lead to a better coordinate solution; the PAR method used in this paper can shorten the convergence time and the coordinate validation strategy can improve the availability of high precision positioning.

AeroMACS system characterization and demonstrations

NASA Astrophysics Data System (ADS)

Kerczewski, R. J.; Apaza, R. D.; Dimond, R. P.

This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

AeroMACS System Characterization and Demonstrations

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

2013-01-01

This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past 3 years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

AeroMACS System Characterization and Demonstrations

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

2013-01-01

The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

47 CFR 90.419 - Points of communication.

Code of Federal Regulations, 2010 CFR

2010-10-01

... communicate between associated mobile stations and associated base stations of the licensee. Accordingly, operations between base stations at fixed locations are permitted only in the following situations: (a) Base... frequencies below 450 MHz, may communicate on a secondary basis with other base stations, operational fixed...

47 CFR 22.413 - Developmental authorization of 72-76 MHz fixed transmitters.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Developmental authorization of 72-76 MHz fixed transmitters. 22.413 Section 22.413 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Developmental Authorizations § 22.413 Developmental authorization...

47 CFR 22.413 - Developmental authorization of 72-76 MHz fixed transmitters.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 2 2012-10-01 2012-10-01 false Developmental authorization of 72-76 MHz fixed transmitters. 22.413 Section 22.413 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Developmental Authorizations § 22.413 Developmental authorization...

47 CFR 22.413 - Developmental authorization of 72-76 MHz fixed transmitters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Developmental authorization of 72-76 MHz fixed transmitters. 22.413 Section 22.413 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Developmental Authorizations § 22.413 Developmental authorization...

Description and performance of a digital mobile satellite terminal

NASA Technical Reports Server (NTRS)

Lay, N.; Jedrey, T.; Parkyn, J.; Divsalar, D.

1990-01-01

A major goal of the Mobile Satellite Experiment (MSAT-X) program at the Jet Propulsion Lab (JPL) is the development of an advanced digital terminal for use in land mobile satellite communication. The terminal has been developed to minimize the risk of applying advanced technologies to future commercial mobile satellite systems (MSS). Testing with existing L band satellites was performed in fixed, land mobile and aeronautical mobile environments. JPL's development and tests of its mobile terminal have demonstrated the viability of narrowband digital voice communications in a land mobile environment through geostationary satellites. This paper provides a consolidated description of the terminal architecture and the performance of its individual elements.

The zinc-loss effect and mobility enhancement of DUV-patterned sol-gel IGZO thin-film transistors

NASA Astrophysics Data System (ADS)

Wang, Kuan-Hsun; Zan, Hsiao-Wen; Soppera, Olivier

2018-03-01

We investigate the composition of the DUV-patterned sol-gel indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) and observe a significant zinc loss effect during developing when the DUV exposure is insufficient. The zinc loss, however, is beneficial for increasing the mobility. Reducing zinc to indium composition ratio from 0.5 to 0.02 can effectively increase mobility from 0.27 to 7.30 cm2 V-1 s-1 when the gallium to indium ratio is fixed as 0.25 and the post annealing process is fixed as 300 °C for 2 h. On the other hand, an IGO TFT fails to deliver a uniform film and a reproducible TFT performance, revealing the critical role of zinc in forming homogeneous IGZO TFTs.

[Rotational mobility of the schoolchildren's vertebral column as a criterion for evaluating its functional status].

PubMed

Akopian, E S; Ter-Marganian, N G

2009-01-01

As known, all movements in the vertebral column are effected in the perpendicular planes and its training is required in all directions. Rotational movements make it possible to activate fixed spinal (thoracic, sacral) mobility, to improve their trophism and innervation and aid to interact all the spinal segments as an integral train. That is the reason why studying the rotational mobility of the vertebral column in children of school age is critically important. The algorithm developed and tested in practice was used to evaluate rotational mobility of the vertebral column (its movement about its axis) in the cervical and lumbar portions. The results of examining the rotational mobility of the cervical portion, which are fixed in all age groups, suggest that it is this spinal portion that is the most vulnerable, sensitive link that is rapidly responsive to its inadequate movements. All the above lends support to the necessity of making the special training of the cervical spine. The results of a pedagogical experiment have allowed the authors to be the first in physical educational practice to develop regional standard scales used to evaluate spinal rotational mobility in schoolchildren.

Golden Proportions for the Generalized Tribonacci Numbers

ERIC Educational Resources Information Center

Shah, Devbhadra V.; Mehta, Darshana A.

2009-01-01

It is known that the ratios of consecutive terms of Fibonacci and Tribonacci sequences converge to the fixed ratio. In this article, we consider the generalized form of Tribonacci numbers and derive the "golden proportion" for the whole family of this generalized sequence. (Contains 2 tables.)

An hp symplectic pseudospectral method for nonlinear optimal control

NASA Astrophysics Data System (ADS)

Peng, Haijun; Wang, Xinwei; Li, Mingwu; Chen, Biaosong

2017-01-01

An adaptive symplectic pseudospectral method based on the dual variational principle is proposed and is successfully applied to solving nonlinear optimal control problems in this paper. The proposed method satisfies the first order necessary conditions of continuous optimal control problems, also the symplectic property of the original continuous Hamiltonian system is preserved. The original optimal control problem is transferred into a set of nonlinear equations which can be solved easily by Newton-Raphson iterations, and the Jacobian matrix is found to be sparse and symmetric. The proposed method, on one hand, exhibits exponent convergence rates when the number of collocation points are increasing with the fixed number of sub-intervals; on the other hand, exhibits linear convergence rates when the number of sub-intervals is increasing with the fixed number of collocation points. Furthermore, combining with the hp method based on the residual error of dynamic constraints, the proposed method can achieve given precisions in a few iterations. Five examples highlight the high precision and high computational efficiency of the proposed method.

THE EVOLUTIONARY HISTORY OF PARTHENOGENETIC CNEMIDOPHORUS LEMNISCATUS (SAURIA, TEIIDAE). I. EVIDENCE FOR A HYBRID ORIGIN.

PubMed

Sites, Jack W; Peccinini-Seale, Denise M; Moritz, Craig; Wright, John W; Brown, Wesley M

1990-07-01

Chromosomes and allozymes were studied from chromosomally distinct unisexual (races B and C) and bisexual (races D and E) populations of the teiid lizard Cnemidophorus lemniscatus, and from selected outgroup taxa (C. murinus, C. nigricolor, Ameiva ameiva, and A. auberi). Karyotyping confirmed the racial identity of individuals and showed that the chromosomal composition of populations at specific localities has remained the same for 20 years. All individuals of both unisexual populations were heterozygous for a pericentric inversion that distinguishes D and E bisexuals. Also, the unisexuals were all heterozygous for 8 of 11 protein loci for which D and E were fixed or nearly fixed for different alleles. Most of these alleles represent derived states relative to the other Cnemidophorus and Ameiva analyzed, and the fixed heterozygote condition at these nine markers provides unequivocal support for the hypothesis that the unisexual C. lemniscatus arose by hybridization between ancestors genetically similar to extant D and E populations. At the remaining three loci for which D and E show fixed differences, the unisexuals were homozygous rather than heterozygous. This suggests that either (1) allozymes have been lost by mutations to null, silent, or convergent mobility states, (2) ancestral genotypes were similar to but not identical with the extant D and E races, and/or (3) limited recombination may occur between unisexual genomes. Allozyme-based genetic distances between D and E were large, suggesting that bisexual races D and E are genetically isolated; each race should be accorded full species status. This conclusion is supported by the absence of any clear biochemical evidence for their monophyly with respect to the other Cnemidophorus examined. Cladistic analyses of 17 phylogenetically informative loci revealed two equally parsimonious shortest trees, one supporting monophyly and the other paraphyly of the C. lemniscatus complex. Further testing of the monophyly of C. lemniscatus requires additional data. With the present study, the evidence that all parthenogenetic Cnemidophorus are of hybrid origin is complete. © 1990 The Society for the Study of Evolution.

Residential segregation and cultural dissemination: An Axelrod-Schelling model

NASA Astrophysics Data System (ADS)

Gracia-Lázaro, C.; Lafuerza, L. F.; Floría, L. M.; Moreno, Y.

2009-10-01

In the Axelrod’s model of cultural dissemination, we consider the mobility of cultural agents through the introduction of a density of empty sites and the possibility that agents in a dissimilar neighborhood can move to them if their mean cultural similarity with the neighborhood is below some threshold. While for low values of the density of empty sites, the mobility enhances the convergence to a global culture, for high enough values of it, the dynamics can lead to the coexistence of disconnected domains of different cultures. In this regime, the increase in initial cultural diversity paradoxically increases the convergence to a dominant culture. Further increase in diversity leads to the fragmentation of the dominant culture into domains, forever changing in shape and number, as an effect of the never ending eroding activity of cultural minorities.

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-09-01

Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to: Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks Integration strategies for multiservice transport platforms Access methods that bridge traditional and emerging services Network signaling and control methodologies All-optical packet routing and switching techniques To submit to this special issue, follow the normal procedure for submission to JON, indicating "Convergence feature" in the "Comments" field of the online submission form. For all other questions relating to this feature issue, please send an e-mail to jon@osa.org, subject line "Convergence." Additional information can be found on the JON website: http://www.osa-jon.org/submission/ Submission Deadline: 1 October 2005

Mobile eHealth interventions for obesity: a timely opportunity to leverage convergence trends.

PubMed

Tufano, James T; Karras, Bryant T

2005-12-20

Obesity is often cited as the most prevalent chronic health condition and highest priority public health problem in the United States. There is a limited but growing body of evidence suggesting that mobile eHealth behavioral interventions, if properly designed, may be effective in promoting and sustaining successful weight loss and weight maintenance behavior changes. This paper reviews the current literature on the successes and failures of public health, provider-administered, and self-managed behavioral health interventions for weight loss. The prevailing theories of health behavior change are discussed from the perspective of how this knowledge can serve as an evidence base to inform the design of mobile eHealth weight loss interventions. Tailored informational interventions, which, in recent years, have proven to be the most effective form of conventional health behavior intervention for weight loss, are discussed. Lessons learned from the success of conventional tailored informational interventions and the early successes of desktop computer-assisted self-help weight management interventions are presented, as are design principles suggested by Social Cognitive Theory and the Social Marketing Model. Relevant computing and communications technology convergence trends are also discussed. The recent trends in rapid advancement, convergence, and public adoption of Web-enabled cellular telephone and wireless personal digital assistant (PDA) devices provide timely opportunities to deliver the mass customization capabilities, reach, and interactivity required for the development, administration, and adoption of effective population-level eHealth tailored informational interventions for obesity.

Convergent Starvation Signals and Hormone Crosstalk in Regulating Nutrient Mobilization upon Germination in Cereals[C][W

PubMed Central

Hong, Ya-Fang; Ho, Tuan-Hua David; Wu, Chin-Feng; Ho, Shin-Lon; Yeh, Rong-Hwei; Lu, Chung-An; Chen, Peng-Wen; Yu, Lin-Chih; Chao, Annlin; Yu, Su-May

2012-01-01

Germination is a unique developmental transition from metabolically quiescent seed to actively growing seedling that requires an ensemble of hydrolases for coordinated nutrient mobilization to support heterotrophic growth until autotrophic photosynthesis is established. This study reveals two crucial transcription factors, MYBS1 and MYBGA, present in rice (Oryza sativa) and barley (Hordeum vulgare), that function to integrate diverse nutrient starvation and gibberellin (GA) signaling pathways during germination of cereal grains. Sugar represses but sugar starvation induces MYBS1 synthesis and its nuclear translocation. GA antagonizes sugar repression by enhancing conuclear transport of the GA-inducible MYBGA with MYBS1 and the formation of a stable bipartite MYB-DNA complex to activate the α-amylase gene. We further discovered that not only sugar but also nitrogen and phosphate starvation signals converge and interconnect with GA to promote the conuclear import of MYBS1 and MYBGA, resulting in the expression of a large set of GA-inducible but functionally distinct hydrolases, transporters, and regulators associated with mobilization of the full complement of nutrients to support active seedling growth in cereals. PMID:22773748

Fugitive methane assessment with mobile and fence line sensors

EPA Science Inventory

There is no published abstract for this short panel talk. The panel presentation titled “Fugitive methane assessment with mobile and fence line sensors” provides a basic introduction to the topic of next generation sensor technologies for identifying and fixing emiss...

47 CFR 1.227 - Consolidations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... application. (ii) Domestic public fixed and public mobile. See Rule § 21.31 of this chapter for the... as to amendments of applications. (iii) Public coast stations (Maritime mobile service). See... issues, or (2) Any applications which present conflicting claims, except where a random selection process...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MOBILE RADIO SERVICES Applications and Authorizations § 90.119 Application requirements. (a) Part 1... Services, including applications for new base, fixed, or mobile station authorizations governed by this... 47 Telecommunication 5 2010-10-01 2010-10-01 false Application requirements. 90.119 Section 90.119...

Hands-Only CPR

MedlinePlus

... specific, especially if you’re calling from a mobile phone as that is not associated with a fixed address. Answering the dispatcher’s questions will not delay the arrival of ... save lives with Hands-Only CPR. Check out the Mobile Tour page to see if we're coming ...

Shaping mobile belts by small-scale convection.

PubMed

Faccenna, Claudio; Becker, Thorsten W

2010-06-03

Mobile belts are long-lived deformation zones composed of an ensemble of crustal fragments, distributed over hundreds of kilometres inside continental convergent margins. The Mediterranean represents a remarkable example of this tectonic setting: the region hosts a diffuse boundary between the Nubia and Eurasia plates comprised of a mosaic of microplates that move and deform independently from the overall plate convergence. Surface expressions of Mediterranean tectonics include deep, subsiding backarc basins, intraplate plateaux and uplifting orogenic belts. Although the kinematics of the area are now fairly well defined, the dynamical origins of many of these active features are controversial and usually attributed to crustal and lithospheric interactions. However, the effects of mantle convection, well established for continental interiors, should be particularly relevant in a mobile belt, and modelling may constrain important parameters such as slab coherence and lithospheric strength. Here we compute global mantle flow on the basis of recent, high-resolution seismic tomography to investigate the role of buoyancy-driven and plate-motion-induced mantle circulation for the Mediterranean. We show that mantle flow provides an explanation for much of the observed dynamic topography and microplate motion in the region. More generally, vigorous small-scale convection in the uppermost mantle may also underpin other complex mobile belts such as the North American Cordillera or the Himalayan-Tibetan collision zone.

Use of a cost accounting system to evaluate costs of a VA special program.

PubMed

Menke, T J; Wray, N P

1999-04-01

The Department of Veterans Affairs (VA) established six mobile clinics to provide care for rural veterans. Each was operated by a parent VA Medical Center (VAMC). To describe the use of a cost-accounting system which does not provide costs at the service or patient level to determine the costs of the mobile clinics. Costs per visit were compared among the mobile clinics with the parent VAMCs and with simulated fixed-location clinics. Cost data came from VA's Centralized Accounting for Local Management (CALM) data. Utilization data came from VA's outpatient file. Information was obtained from the VAMCs' fiscal services to reallocate costs among the CALM subaccounts to generate cost data that was comparable among the mobile clinics. Costs per visit for the mobile clinics were twice as high as those of the parent VAMCs. Costs per visit would be lower at fixed-location clinics unless the volume were substantially less than that provided by the mobile clinics. Differences between cost allocations for accounting purposes and research are likely to necessitate adjusting cost accounting data for research purposes. Fortunately, information from the accountants or primary data can lead to a cost database which is appropriate for research evaluations. In the mobile clinics study, the analysis of cost accounting data led to the conclusion that mobile clinics were not a cost-effective way in which to provide care to rural veterans.

Rapid ambiguity resolution over medium-to-long baselines based on GPS/BDS multi-frequency observables

NASA Astrophysics Data System (ADS)

Gong, Xiaopeng; Lou, Yidong; Liu, Wanke; Zheng, Fu; Gu, Shengfeng; Wang, Hua

2017-02-01

Medium-long baseline RTK positioning generally needs a long initial time to find an accurate position due to non-negligible atmospheric delay residual. In order to shorten the initial or re-convergence time, a rapid phase ambiguity resolution method is employed based on GPS/BDS multi-frequency observables in this paper. This method is realized by two steps. First, double-differenced un-combined observables (i.e., L1/L2 and B1/B2/B3 observables) are used to obtain a float solution with atmospheric delay estimated as random walk parameter by using Kalman filter. This model enables an easy and consistent implementation for different systems and different frequency observables and can readily be extended to use more satellite navigation systems (e.g., Galileo, QZSS). Additional prior constraints for atmospheric information can be quickly added as well, because atmospheric delay is parameterized. Second, in order to fix ambiguity rapidly and reliably, ambiguities are divided into three types (extra-wide-lane (EWL), wide-lane (WL) and narrow-lane (NL)) according to their wavelengths and are to be fixed sequentially by using the LAMBDA method. Several baselines ranging from 61 km to 232 km collected by Trimble and Panda receivers are used to validate the method. The results illustrate that it only takes approximately 1, 2 and 6 epochs (30 s intervals) to fix EWL, WL and NL ambiguities, respectively. More epochs' observables are needed to fix WL and NL ambiguity around local time 14:00 than other time mainly due to more active ionosphere activity. As for the re-convergence time, the simulated results show that 90% of epochs can be fixed within 2 epochs by using prior atmospheric delay information obtained from previously 5 min. Finally, as for positioning accuracy, meter, decimeter and centimeter level positioning results are obtained according to different ambiguity resolution performances, i.e., EWL, WL and NL fixed solutions.

Distributed synchronization of networked drive-response systems: A nonlinear fixed-time protocol.

PubMed

Zhao, Wen; Liu, Gang; Ma, Xi; He, Bing; Dong, Yunfeng

2017-11-01

The distributed synchronization of networked drive-response systems is investigated in this paper. A novel nonlinear protocol is proposed to ensure that the tracking errors converge to zeros in a fixed-time. By comparison with previous synchronization methods, the present method considers more practical conditions and the synchronization time is not dependent of arbitrary initial conditions but can be offline pre-assign according to the task assignment. Finally, the feasibility and validity of the presented protocol have been illustrated by a numerical simulation. Copyright © 2017. Published by Elsevier Ltd.

Solving the multiple-set split equality common fixed-point problem of firmly quasi-nonexpansive operators.

PubMed

Zhao, Jing; Zong, Haili

2018-01-01

In this paper, we propose parallel and cyclic iterative algorithms for solving the multiple-set split equality common fixed-point problem of firmly quasi-nonexpansive operators. We also combine the process of cyclic and parallel iterative methods and propose two mixed iterative algorithms. Our several algorithms do not need any prior information about the operator norms. Under mild assumptions, we prove weak convergence of the proposed iterative sequences in Hilbert spaces. As applications, we obtain several iterative algorithms to solve the multiple-set split equality problem.

ETS-VI multibeam satellite communications systems

NASA Astrophysics Data System (ADS)

Kawai, Makoto; Tanaka, Masayoshi; Ohtomo, Isao

1989-10-01

The fixed and mobile satellite communications systems of the Japanese Engineering Test Satellite-VI (ETS-VI) are described. The system requirements are outlined along with the system configuration. The ETS-VI multibeam system employs three frequency bands. When used for Ka-band fixed communications, it covers the Japanese main islands with thirteen 0.3-degree-wide spot beam. Four of the beams are active for ETS-VI. When used for S-band mobile communications, five beams cover the area within 200 nautical miles from the Japanese coast. The C-band beam for fixed communications covers the central area of the Japanese main islands with a single beam. The onboard antenna system is described along with the transponders and their associated onboard systems. A discussion of the system technology follows, covering the TDMA transmisssion system, the relay function, rainfall compensation, and the antenna and propagation performance.

Interworking evolution of mobile satellite and terrestrial networks

NASA Technical Reports Server (NTRS)

Matyas, R.; Kelleher, P.; Moller, P.; Jones, T.

1993-01-01

There is considerable interest among mobile satellite service providers in interworking with terrestrial networks to provide a universal global network. With such interworking, subscribers may be provided a common set of services such as those planned for the Public Switched Telephone Network (PSTN), the Integrated Services Digital Network (ISDN), and future Intelligent Networks (IN's). This paper first reviews issues in satellite interworking. Next the status and interworking plans of terrestrial mobile communications service providers are examined with early examples of mobile satellite interworking including a discussion of the anticipated evolution towards full interworking between mobile satellite and both fixed and mobile terrestrial networks.

Multidimensional stochastic approximation using locally contractive functions

NASA Technical Reports Server (NTRS)

Lawton, W. M.

1975-01-01

A Robbins-Monro type multidimensional stochastic approximation algorithm which converges in mean square and with probability one to the fixed point of a locally contractive regression function is developed. The algorithm is applied to obtain maximum likelihood estimates of the parameters for a mixture of multivariate normal distributions.

Portable work zone barrier-"mobile barriers" mobile barrier trailer : final report, December 2009.

DOT National Transportation Integrated Search

2009-12-01

This work has focused on the fabrication and implementation of the MBT-1 Beam which is a : truck mounted, moveable, expandable beam that provides positive work zone protection : comparable to a fixed concrete barrier. It is specifically intended to e...

47 CFR 101.805 - Assignment of frequencies to mobile stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Assignment of frequencies to mobile stations. 101.805 Section 101.805 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.805 Assignment...

47 CFR 101.805 - Assignment of frequencies to mobile stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Assignment of frequencies to mobile stations. 101.805 Section 101.805 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.805 Assignment...

47 CFR 101.805 - Assignment of frequencies to mobile stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Assignment of frequencies to mobile stations. 101.805 Section 101.805 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.805 Assignment...

47 CFR 101.805 - Assignment of frequencies to mobile stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Assignment of frequencies to mobile stations. 101.805 Section 101.805 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.805 Assignment...

47 CFR 101.805 - Assignment of frequencies to mobile stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Assignment of frequencies to mobile stations. 101.805 Section 101.805 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.805 Assignment...

Arbitrary Steady-State Solutions with the K-epsilon Model

NASA Technical Reports Server (NTRS)

Rumsey, Christopher L.; Pettersson Reif, B. A.; Gatski, Thomas B.

2006-01-01

Widely-used forms of the K-epsilon turbulence model are shown to yield arbitrary steady-state converged solutions that are highly dependent on numerical considerations such as initial conditions and solution procedure. These solutions contain pseudo-laminar regions of varying size. By applying a nullcline analysis to the equation set, it is possible to clearly demonstrate the reasons for the anomalous behavior. In summary, the degenerate solution acts as a stable fixed point under certain conditions, causing the numerical method to converge there. The analysis also suggests a methodology for preventing the anomalous behavior in steady-state computations.

Augmenting the one-shot framework by additional constraints

DOE PAGES

Bosse, Torsten

2016-05-12

The (multistep) one-shot method for design optimization problems has been successfully implemented for various applications. To this end, a slowly convergent primal fixed-point iteration of the state equation is augmented by an adjoint iteration and a corresponding preconditioned design update. In this paper we present a modification of the method that allows for additional equality constraints besides the usual state equation. Finally, a retardation analysis and the local convergence of the method in terms of necessary and sufficient conditions are given, which depend on key characteristics of the underlying problem and the quality of the utilized preconditioner.

Augmenting the one-shot framework by additional constraints

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

Bosse, Torsten

The (multistep) one-shot method for design optimization problems has been successfully implemented for various applications. To this end, a slowly convergent primal fixed-point iteration of the state equation is augmented by an adjoint iteration and a corresponding preconditioned design update. In this paper we present a modification of the method that allows for additional equality constraints besides the usual state equation. Finally, a retardation analysis and the local convergence of the method in terms of necessary and sufficient conditions are given, which depend on key characteristics of the underlying problem and the quality of the utilized preconditioner.

Numerical pricing of options using high-order compact finite difference schemes

NASA Astrophysics Data System (ADS)

Tangman, D. Y.; Gopaul, A.; Bhuruth, M.

2008-09-01

We consider high-order compact (HOC) schemes for quasilinear parabolic partial differential equations to discretise the Black-Scholes PDE for the numerical pricing of European and American options. We show that for the heat equation with smooth initial conditions, the HOC schemes attain clear fourth-order convergence but fail if non-smooth payoff conditions are used. To restore the fourth-order convergence, we use a grid stretching that concentrates grid nodes at the strike price for European options. For an American option, an efficient procedure is also described to compute the option price, Greeks and the optimal exercise curve. Comparisons with a fourth-order non-compact scheme are also done. However, fourth-order convergence is not experienced with this strategy. To improve the convergence rate for American options, we discuss the use of a front-fixing transformation with the HOC scheme. We also show that the HOC scheme with grid stretching along the asset price dimension gives accurate numerical solutions for European options under stochastic volatility.

Results with nine years mean follow up on one hundred and three KAPS® uni knee arthroplasties: eighty six medial and seventeen lateral.

PubMed

Saragaglia, Dominique; Bevand, Adrien; Refaie, Ramsay; Rubens-Duval, Brice; Pailhé, Régis

2018-05-01

The purpose of this study was to present the results of the KAPS® uni knee arthroplasty system, both mobile and fixed bearing with reference to function, alignment and complications in 103 implants with a mean follow-up of nine years. This was a retrospective study of 103 unicompartimental knee arthroplasties in 89 patients operated on between March 2005 and March 2010. The population was composed of 50 males and 39 females, with a mean age of 70.5 ± 7.5 years (41 - 90). Eighty-seven patients had a genu varum deformity (84.5%), one of whom had an osteoid osteoma of the lateral tibial plateau and 16 patients had a genu valgum (15.5%). Eighty-six medial prostheses were implanted (82 mobile bearings and 4 fixed bearings) and 17 lateral prostheses (all fixed bearings) including the osteoid osteoma. At a mean follow-up of 107.5 months (73-138), 72 knees (58 patients) were reviewed (70%). The mean IKS score was of 173 ± 31 points (58 - 200). The mean Oxford knee score was 21 ± 8 points (12 - 50). The cumulated survival rate at a follow up of 132 months was 98.2%. The KAPS® unicompartmental knee arthroplasty gives efficacious and safe outcomes in the majority of cases at a mean follow-up of nine years. The availability of both fixed and mobile bearings with the same instrumentation, allowing to choose the right implant intra-operatively, is a great advantage in order to avoid the occurrence of some complications, specific to mobile bearing prostheses (dislocation and over-correction).

Factors affecting the impingement angle of fixed- and mobile-bearing total knee replacements: a laboratory study.

PubMed

Walker, Peter S; Yildirim, Gokce; Sussman-Fort, Jon; Roth, Jonathan; White, Brian; Klein, Gregg R

2007-08-01

Maximum flexion-or impingement angle-is defined as the angle of flexion when the posterior femoral cortex impacts the posterior edge of the tibial insert. We examined the effects of femoral component placement on the femur, the slope angle of the tibial component, the location of the femoral-tibial contact point, and the amount of internal or external rotation. Posterior and proximal femoral placement, a more posterior femoral-tibial contact point, and a more tibial slope all increased maximum flexion, whereas rotation reduced it. A mobile-bearing knee gave results similar to those of the fixed-bearing knee, but there was no loss of flexion in internal or external rotation if the mobile bearing moved with the femur. In the absence of negative factors, a flexion angle of 150 degrees can be reached before impingement.

Hole mobility in various transition-metal-oxides doped organic semiconductor films

NASA Astrophysics Data System (ADS)

Yoo, Seung-Jun; Lee, Jeong-Hwan; Kim, Jae-Min; Kim, Jang-Joo

2017-01-01

Hole mobility in various p-doped organic semiconductors possessing different energetic disorder parameters in low-to-moderate doping range is reported. The hole mobility is reduced by orders of magnitude and converged to 10-7-10-6 cm2/Vs at a doping concentration of 5 mol. % for all the materials, even though the pristine organic films possess orders of magnitude of different mobilities from 10-5 to 10-3 cm2/Vs. These results indicate that the ionized dopants behave as traps for generated carriers to reduce the mobility. Further increase in the doping concentration either increases or decreases the mobility depending on the energetic disorder parameters of the organic films. These phenomena are interpreted based on the Coulomb trap depth of the ionized dopants and energetic disorder of the host layers.

47 CFR 101.813 - Remote control operation of mobile television pickup stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Remote control operation of mobile television pickup stations. 101.813 Section 101.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101...

47 CFR 101.813 - Remote control operation of mobile television pickup stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Remote control operation of mobile television pickup stations. 101.813 Section 101.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101...

47 CFR 101.813 - Remote control operation of mobile television pickup stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Remote control operation of mobile television pickup stations. 101.813 Section 101.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101...

47 CFR 101.813 - Remote control operation of mobile television pickup stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Remote control operation of mobile television pickup stations. 101.813 Section 101.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101...

47 CFR 101.813 - Remote control operation of mobile television pickup stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Remote control operation of mobile television pickup stations. 101.813 Section 101.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101...

Supporting Mobile Collaborative Activities through Scaffolded Flexible Grouping

ERIC Educational Resources Information Center

Boticki, Ivica; Looi, Chee-Kit; Wong, Lung-Hsiang

2011-01-01

Within the field of Mobile Computer-Supported Collaborative Learning (mCSCL), we are interested in exploring the space of collaborative activities that enable students to practice communication, negotiation and decision-making skills. Collaboration is via learning activities that circumvent the constraints of fixed seating or locations of…

Theoretical Foundations of Active Learning

DTIC Science & Technology

2009-05-01

on the rate of convergence of the loss of an estimator, as a function of the number of labeled examples observed [e.g., Benedek and Itai , 1988...1537, 2005. 2.8 G. Benedek and A. Itai . Learnability by fixed distributions. In Proc. of the First Workshop on Computational Learning Theory, pages 80

Study on the fixed point in crustal deformation before strong earthquake

NASA Astrophysics Data System (ADS)

Niu, A.; Li, Y.; Yan, W. Mr

2017-12-01

Usually, scholars believe that the fault pre-sliding or expansion phenomenon will be observed near epicenter area before strong earthquake, but more and more observations show that the crust deformation nearby epicenter area is smallest(Zhou, 1997; Niu,2009,2012;Bilham, 2005; Amoruso et al., 2010). The theory of Fixed point t is a branch of mathematics that arises from the theory of topological transformation and has important applications in obvious model analysis. An important precursory was observed by two tilt-meter sets, installed at Wenchuan Observatory in the epicenter area, that the tilt changes were the smallest compared with the other 8 stations around them in one year before the Wenchuan earthquake. To subscribe the phenomenon, we proposed the minimum annual variation range that used as a topological transformation. The window length is 1 year, and the sliding length is 1 day. The convergence of points with minimum annual change in the 3 years before the Wenchuan earthquake is studied. And the results show that the points with minimum deformation amplitude basically converge to the epicenter region before the earthquake. The possible mechanism of fixed point of crustal deformation was explored. Concerning the fixed point of crust deformation, the liquidity of lithospheric medium and the isostasy theory are accepted by many scholars (Bott &Dean, 1973; Merer et al.1988; Molnar et al., 1975,1978; Tapponnier et al., 1976; Wang et al., 2001). To explain the fixed point of crust deformation before earthquakes, we study the plate bending model (Bai, et al., 2003). According to plate bending model and real deformation data, we have found that the earthquake rupture occurred around the extreme point of plate bending, where the velocities of displacement, tilt, strain, gravity and so on are close to zero, and the fixed points are located around the epicenter.The phenomenon of fixed point of crust deformation is different from former understandings about the earthquake rupture precursor. 1) The observations for crust deformation in natural conditions are different with dry and static experiments, and the former had the meaning of stress wave.2)The earthquake rupture has a special triggering mechanism that is different from the experiment with limited scale rock fracture.

On adaptive learning rate that guarantees convergence in feedforward networks.

PubMed

Behera, Laxmidhar; Kumar, Swagat; Patnaik, Awhan

2006-09-01

This paper investigates new learning algorithms (LF I and LF II) based on Lyapunov function for the training of feedforward neural networks. It is observed that such algorithms have interesting parallel with the popular backpropagation (BP) algorithm where the fixed learning rate is replaced by an adaptive learning rate computed using convergence theorem based on Lyapunov stability theory. LF II, a modified version of LF I, has been introduced with an aim to avoid local minima. This modification also helps in improving the convergence speed in some cases. Conditions for achieving global minimum for these kind of algorithms have been studied in detail. The performances of the proposed algorithms are compared with BP algorithm and extended Kalman filtering (EKF) on three bench-mark function approximation problems: XOR, 3-bit parity, and 8-3 encoder. The comparisons are made in terms of number of learning iterations and computational time required for convergence. It is found that the proposed algorithms (LF I and II) are much faster in convergence than other two algorithms to attain same accuracy. Finally, the comparison is made on a complex two-dimensional (2-D) Gabor function and effect of adaptive learning rate for faster convergence is verified. In a nutshell, the investigations made in this paper help us better understand the learning procedure of feedforward neural networks in terms of adaptive learning rate, convergence speed, and local minima.

New gliding mammaliaforms from the Jurassic

NASA Astrophysics Data System (ADS)

Meng, Qing-Jin; Grossnickle, David M.; Liu, Di; Zhang, Yu-Guang; Neander, April I.; Ji, Qiang; Luo, Zhe-Xi

2017-08-01

Stem mammaliaforms are Mesozoic forerunners to mammals, and they offer critical evidence for the anatomical evolution and ecological diversification during the earliest mammalian history. Two new eleutherodonts from the Late Jurassic period have skin membranes and skeletal features that are adapted for gliding. Characteristics of their digits provide evidence of roosting behaviour, as in dermopterans and bats, and their feet have a calcaneal calcar to support the uropagatium as in bats. The new volant taxa are phylogenetically nested with arboreal eleutherodonts. Together, they show an evolutionary experimentation similar to the iterative evolutions of gliders within arboreal groups of marsupial and placental mammals. However, gliding eleutherodonts possess rigid interclavicle-clavicle structures, convergent to the avian furculum, and they retain shoulder girdle plesiomorphies of mammaliaforms and monotremes. Forelimb mobility required by gliding occurs at the acromion-clavicle and glenohumeral joints, is different from and convergent to the shoulder mobility at the pivotal clavicle-sternal joint in marsupial and placental gliders.

Fixed Point Learning Based Intelligent Traffic Control System

NASA Astrophysics Data System (ADS)

Zongyao, Wang; Cong, Sui; Cheng, Shao

2017-10-01

Fixed point learning has become an important tool to analyse large scale distributed system such as urban traffic network. This paper presents a fixed point learning based intelligence traffic network control system. The system applies convergence property of fixed point theorem to optimize the traffic flow density. The intelligence traffic control system achieves maximum road resources usage by averaging traffic flow density among the traffic network. The intelligence traffic network control system is built based on decentralized structure and intelligence cooperation. No central control is needed to manage the system. The proposed system is simple, effective and feasible for practical use. The performance of the system is tested via theoretical proof and simulations. The results demonstrate that the system can effectively solve the traffic congestion problem and increase the vehicles average speed. It also proves that the system is flexible, reliable and feasible for practical use.

A method of undifferenced ambiguity resolution for GPS+GLONASS precise point positioning

PubMed Central

Yi, Wenting; Song, Weiwei; Lou, Yidong; Shi, Chuang; Yao, Yibin

2016-01-01

Integer ambiguity resolution is critical for achieving positions of high precision and for shortening the convergence time of precise point positioning (PPP). However, GLONASS adopts the signal processing technology of frequency division multiple access and results in inter-frequency code biases (IFCBs), which are currently difficult to correct. This bias makes the methods proposed for GPS ambiguity fixing unsuitable for GLONASS. To realize undifferenced GLONASS ambiguity fixing, we propose an undifferenced ambiguity resolution method for GPS+GLONASS PPP, which considers the IFCBs estimation. The experimental result demonstrates that the success rate of GLONASS ambiguity fixing can reach 75% through the proposed method. Compared with the ambiguity float solutions, the positioning accuracies of ambiguity-fixed solutions of GLONASS-only PPP are increased by 12.2%, 20.9%, and 10.3%, and that of the GPS+GLONASS PPP by 13.0%, 35.2%, and 14.1% in the North, East and Up directions, respectively. PMID:27222361

A method of undifferenced ambiguity resolution for GPS+GLONASS precise point positioning.

PubMed

Yi, Wenting; Song, Weiwei; Lou, Yidong; Shi, Chuang; Yao, Yibin

2016-05-25

Integer ambiguity resolution is critical for achieving positions of high precision and for shortening the convergence time of precise point positioning (PPP). However, GLONASS adopts the signal processing technology of frequency division multiple access and results in inter-frequency code biases (IFCBs), which are currently difficult to correct. This bias makes the methods proposed for GPS ambiguity fixing unsuitable for GLONASS. To realize undifferenced GLONASS ambiguity fixing, we propose an undifferenced ambiguity resolution method for GPS+GLONASS PPP, which considers the IFCBs estimation. The experimental result demonstrates that the success rate of GLONASS ambiguity fixing can reach 75% through the proposed method. Compared with the ambiguity float solutions, the positioning accuracies of ambiguity-fixed solutions of GLONASS-only PPP are increased by 12.2%, 20.9%, and 10.3%, and that of the GPS+GLONASS PPP by 13.0%, 35.2%, and 14.1% in the North, East and Up directions, respectively.

Exploring the read-write genome: mobile DNA and mammalian adaptation.

PubMed

Shapiro, James A

2017-02-01

The read-write genome idea predicts that mobile DNA elements will act in evolution to generate adaptive changes in organismal DNA. This prediction was examined in the context of mammalian adaptations involving regulatory non-coding RNAs, viviparous reproduction, early embryonic and stem cell development, the nervous system, and innate immunity. The evidence shows that mobile elements have played specific and sometimes major roles in mammalian adaptive evolution by generating regulatory sites in the DNA and providing interaction motifs in non-coding RNA. Endogenous retroviruses and retrotransposons have been the predominant mobile elements in mammalian adaptive evolution, with the notable exception of bats, where DNA transposons are the major agents of RW genome inscriptions. A few examples of independent but convergent exaptation of mobile DNA elements for similar regulatory rewiring functions are noted.

Crustal dynamics project data analysis, 1991: VLBI geodetic results, 1979 - 1990

NASA Technical Reports Server (NTRS)

Ma, C.; Ryan, J. W.; Caprette, D. S.

1992-01-01

The Goddard VLBI group reports the results of analyzing 1412 Mark II data sets acquired from fixed and mobile observing sites through the end of 1990 and available to the Crustal Dynamics Project. Three large solutions were used to obtain Earth rotation parameters, nutation offsets, global source positions, site velocities, and baseline evolution. Site positions are tabulated on a yearly basis from 1979 through 1992. Site velocities are presented in both geocentric Cartesian coordinates and topocentric coordinates. Baseline evolution is plotted for 175 baselines. Rates are computed for earth rotation and nutation parameters. Included are 104 sources, 88 fixed stations and mobile sites, and 688 baselines.

Warranty-Guarantee Application Guidelines for Air Force Ground Electronic Equipment.

DTIC Science & Technology

1980-02-01

perform the on-equipment maintenance. The procedure is comparable to existing Mobile Depot Mainte- nance. The extended outage of failed equipment may be...currently computed. However, because the equipment is fixed geographically, in contrast to the mobility of avionics equipment, operating-time logs could...base environment, many other items of ground equip- ment are deployed at a remote location or, particularly in TAC, may be mobile equipment not

Using a Smart City IoT to Incentivise and Target Shifts in Mobility Behaviour—Is It a Piece of Pie?

PubMed Central

Poslad, Stefan; Ma, Athen; Wang, Zhenchen; Mei, Haibo

2015-01-01

Whilst there is an increasing capability to instrument smart cities using fixed and mobile sensors to produce the big data to better understand and manage transportation use, there still exists a wide gap between the sustainability goals of smart cities, e.g., to promote less private car use at peak times, with respect to their ability to more dynamically support individualised shifts in multi-modal transportation use to help achieve such goals. We describe the development of the tripzoom system developed as part of the SUNSET—SUstainable social Network SErvices for Transport—project to research and develop a mobile and fixed traffic sensor system to help facilitate individual mobility shifts. Its main novelty was its ability to use mobile sensors to classify common multiple urban transportation modes, to generate information-rich individual and group mobility profiles and to couple this with the use of a targeted incentivised marketplace to gamify travel. This helps to promote mobility shifts towards achieving sustainability goals. This system was trialled in three European country cities operated as Living Labs over six months. Our main findings were that we were able to accomplish a level of behavioural shifts in travel behaviour. Hence, we have provided a proof-of-concept system that uses positive incentives to change individual travel behaviour. PMID:26053752

Using a Smart City IoT to Incentivise and Target Shifts in Mobility Behaviour--Is It a Piece of Pie?

PubMed

Poslad, Stefan; Ma, Athen; Wang, Zhenchen; Mei, Haibo

2015-06-04

Whilst there is an increasing capability to instrument smart cities using fixed and mobile sensors to produce the big data to better understand and manage transportation use, there still exists a wide gap between the sustainability goals of smart cities, e.g., to promote less private car use at peak times, with respect to their ability to more dynamically support individualised shifts in multi-modal transportation use to help achieve such goals. We describe the development of the tripzoom system developed as part of the SUNSET-SUstainable social Network SErvices for Transport-project to research and develop a mobile and fixed traffic sensor system to help facilitate individual mobility shifts. Its main novelty was its ability to use mobile sensors to classify common multiple urban transportation modes, to generate information-rich individual and group mobility profiles and to couple this with the use of a targeted incentivised marketplace to gamify travel. This helps to promote mobility shifts towards achieving sustainability goals. This system was trialled in three European country cities operated as Living Labs over six months. Our main findings were that we were able to accomplish a level of behavioural shifts in travel behaviour. Hence, we have provided a proof-of-concept system that uses positive incentives to change individual travel behaviour.

Multi-vehicle mobility allowance shuttle transit (MAST) system : an analytical model to select the fleet size and a scheduling heuristic.

DOT National Transportation Integrated Search

2012-06-01

The mobility allowance shuttle transit (MAST) system is a hybrid transit system in which vehicles are : allowed to deviate from a fixed route to serve flexible demand. A mixed integer programming (MIP) : formulation for the static scheduling problem ...

Constructing a Multimedia Mobile Classroom Using a Novel Feedback System

ERIC Educational Resources Information Center

Huang, Wen-Chen; Chen, Ching-Wen; Weng, Richard

2015-01-01

In the conventional classroom, many obstacles hinder interaction between an instructor and students, such as limited class hours, fixed seating, and inadequate time for meetings after class. This work develops a novel multimedia mobile classroom feedback system (MMCFS) that instantly displays students' responses, such as class-related questions or…

46 CFR 110.10-1 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

...-31; 111.105-39; 111.105-40; 113.05-7; and (2) Rules for Building and Classing Mobile Offshore... Installations of Ships and Mobile and Fixed Offshore Units—Part 1: Procedures for Calculating Short-Circuit... Park, NC 27709: (1) RP 12.6, Wiring Practices for Hazardous (Classified) Locations Instrumentation Part...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire-extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire-extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operation of internal transmitter control systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control...

47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Operation of internal transmitter control systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control...

47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Operation of internal transmitter control systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control...

47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Operation of internal transmitter control systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control...

47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Operation of internal transmitter control systems through licensed fixed control points. 90.473 Section 90.473 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control...

Increased risk of aseptic loosening for 43,525 rotating-platform vs. fixed-bearing total knee replacements

PubMed Central

Gothesen, Oystein; Lygre, Stein Hakon L; Lorimer, Michelle; Graves, Stephen; Furnes, Ove

2017-01-01

Background and purpose — Given similar functional outcomes with mobile and fixed bearings, a difference in survivorship may favor either. This study investigated the risk of aseptic loosening for the most used subtypes of mobile-bearing rotating-platform knees, in Norway and Australia. Patients and methods — Primary TKRs reported to the Norwegian and Australian joint registries, between 2003 and 2014, were analyzed with aseptic loosening as primary end-point and all revisions as secondary end-point. We hypothesized that no difference would be found in the rate of revision between rotating-platform and the most used fixed-bearing TKRs, or between keeled and non-keeled tibia. Kaplan–Meier estimates and curves, and Cox regression relative risk estimates adjusted for age, sex, and diagnosis were used for comparison. Results — The rotating-platform TKRs had an increased risk of revision for aseptic loosening compared with the most used fixed-bearing knees, in Norway (RR =6, 95% CI 4–8) and Australia (RR =2.1, 95% CI 1.8–2.5). The risk of aseptic loosening as a reason for revision was highest in Norway compared with Australia (RR =1.7, 95% CI 1.4–2.0). The keeled tibial component had the same risk of aseptic loosening as the non-keeled tibia (Australia). Fixation method and subtypes of the tibial components had no impact on the risk of aseptic loosening in these mobile-bearing knees. Interpretation — The rotating-platform TKRs in this study appeared to have a higher risk of revision for aseptic loosening than the most used fixed-bearing TKRs. PMID:28929828

A Mobility-Aware QoS Signaling Protocol for Ambient Networks

NASA Astrophysics Data System (ADS)

Jeong, Seong-Ho; Lee, Sung-Hyuck; Bang, Jongho

Mobility-aware quality of service (QoS) signaling is crucial to provide seamless multimedia services in the ambient environment where mobile nodes may move frequently between different wireless access networks. The mobility of an IP-based node in ambient networks affects routing paths, and as a result, can have a significant impact on the operation and state management of QoS signaling protocols. In this paper, we first analyze the impact of mobility on QoS signaling protocols and how the protocols operate in mobility scenarios. We then propose an efficient mobility-aware QoS signaling protocol which can operate adaptively in ambient networks. The key features of the protocol include the fast discovery of a crossover node where the old and new paths converge or diverge due to handover and the localized state management for seamless services. Our analytical and simulation/experimental results show that the proposed/implemented protocol works better than existing protocols in the IP-based mobile environment.

Photonic sensor applications in transportation security

NASA Astrophysics Data System (ADS)

Krohn, David A.

2007-09-01

There is a broad range of security sensing applications in transportation that can be facilitated by using fiber optic sensors and photonic sensor integrated wireless systems. Many of these vital assets are under constant threat of being attacked. It is important to realize that the threats are not just from terrorism but an aging and often neglected infrastructure. To specifically address transportation security, photonic sensors fall into two categories: fixed point monitoring and mobile tracking. In fixed point monitoring, the sensors monitor bridge and tunnel structural health and environment problems such as toxic gases in a tunnel. Mobile tracking sensors are being designed to track cargo such as shipboard cargo containers and trucks. Mobile tracking sensor systems have multifunctional sensor requirements including intrusion (tampering), biochemical, radiation and explosives detection. This paper will review the state of the art of photonic sensor technologies and their ability to meet the challenges of transportation security.

Kinetic Model Development for the Combustion of Particulate Matter from Conventional and Soy Methyl Ester Diesel Fuels

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

Strzelec, Andrea

2009-12-01

The primary objective of this research has been to investigate how the oxidation characteristics of diesel particulate matter (PM) are affected by blending soy-based biodiesel fuel with conventional ultra low sulfur diesel (ULSD) fuel. PM produced in a light duty engine from different biodiesel-conventional fuel blends was subjected to a range of physical and chemical measurements in order to better understand the mechanisms by which fuel-related changes to oxidation reactivity are brought about. These observations were then incorporated into a kinetic model to predict PM oxidation. Nanostructure of the fixed carbon was investigated by HR-TEM and showed that particulates frommore » biodiesel had a more open structure than particulates generated from conventional diesel fuel, which was confirmed by BET surface area measurements. Surface area evolution with extent of oxidation reaction was measured for PM from ULSD and biodiesel. Biodiesel particulate has a significantly larger surface area for the first 40% of conversion, at which point the samples become quite similar. Oxidation characteristics of nascent PM and the fixed carbon portion were measured by temperature programmed oxidation (TPO) and it was noted that increased biodiesel blending lowered the light-off temperature as well as the temperature where the peak rate of oxidation occurred. A shift in the oxidation profiles of all fuels was seen when the mobile carbon fraction was removed, leaving only the fixed carbon, however the trend in temperature advantage of the biofuel blending remained. The mobile carbon fraction was measured by temperature programmed desorption found to generally increase with increasing biodiesel blend level. The relative change in the light-off temperatures for the nascent and fixed carbon samples was found to be related to the fraction of mobile carbon. Effective Arrhenius parameters for fixed carbon oxidation were directly measured with isothermal, differential oxidation experiments. Normalizing the reaction rate to the total carbon surface area available for reaction allowed for the definition of a single reaction rate with constant activation energy (112.5 {+-} 5.8 kJ/mol) for the oxidation of PM, independent of its fuel source. A kinetic model incorporating the surface area dependence of fixed carbon oxidation rate and the impact of the mobile carbon fraction was constructed and validated against experimental data.« less

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2004-12-01

Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and data, video and data, private-line and virtual private-line, fixed and mobile, and local and long-haul services. These trends have many consequences for consumers, vendors, and carriers. Faced with large volumes of low-margin data traffic mixed with traditional voice services, the need for capital conservation and operational efficiency drives carriers away from today's separate overlay networks for each service and towards "converged" platforms. For example, cable operators require transport of multiple services over both hybrid fiber coax (HFC) and DWDM transport technologies. Local carriers seek an economical architecture to deliver integrated services on optically enabled broadband-access networks. Services over wireless-access networks must coexist with those from wired networks. In each case, convergence of networks and services inspires an important set of questions and challenges, driven by the need for low cost, operational efficiency, service performance requirements, and optical transport technology options. This Feature Issue explores the various interpretations and implications of network convergence pertinent to optical networking. How does convergence affect the evolution of optical transport-layer and control approaches? Are the implied directions consistent with research vision for optical networks? Substantial challenges remain. Papers are solicited across the broad spectrum of interests. These include, but are not limited to:

• Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks
• Integration strategies for multiservice transport platforms
• Access methods that bridge traditional and emerging services
• Network signaling and control methodologies
• All-optical packet routing and switching techniques

Manuscript Submission

Fixing the Mobility Air Forces New Way

DTIC Science & Technology

2013-03-01

Stenner explains, “Our units and people make outstanding contributions to the national defense. Every day, we leverage a portion of the strategic...calculate the ARC’s contribution to the military’s global reach.78 The cost effectiveness that General Stenner refers to is only one of at least three...Department of the Air Force, Mobilization Planning, 18. 60 Ibid. 61 U.S. Department of the Air Force, Mobilization Planning, 9. 62 Charles E. Stenner

Research Needs to Reduce Maritime Collisions, Rammings, and Groundings.

DTIC Science & Technology

1981-05-01

increasingly important as sources of oil and minerals. Thus, the maritime industry must now accommodate unfamiliar fixed and mobile facilities, different...vulnerable to the influence of the press. The news media’s ability to mobilize public opinion for or against any industry, including the maritime industry...allocation for maritime and aeronautical mobile radio service) RTCM Supplement to paper 37-77/SC-69-70, Special Committee 60 Report on Marine Radio

Strong Convergence of Iteration Processes for Infinite Family of General Extended Mappings

NASA Astrophysics Data System (ADS)

Hussein Maibed, Zena

2018-05-01

The aim of this paper, we introduce a concept of general extended mapping which is independent of nonexpansive mapping and give an iteration process of families of quasi nonexpansive and of general extended mappings. Also, the existence of common fixed point are studied for these process in the Hilbert spaces.

Coded aperture ptychography: uniqueness and reconstruction

NASA Astrophysics Data System (ADS)

Chen, Pengwen; Fannjiang, Albert

2018-02-01

Uniqueness of solution is proved for any ptychographic scheme with a random mask under a minimum overlap condition and local geometric convergence analysis is given for the alternating projection (AP) and Douglas-Rachford (DR) algorithms. DR is shown to possess a unique fixed point in the object domain and for AP a simple criterion for distinguishing the true solution among possibly many fixed points is given. A minimalist scheme, where the adjacent masks overlap 50% of the area and each pixel of the object is illuminated by exactly four illuminations, is conveniently parametrized by the number q of shifted masks in each direction. The lower bound 1  -  C/q 2 is proved for the geometric convergence rate of the minimalist scheme, predicting a poor performance with large q which is confirmed by numerical experiments. The twin-image ambiguity is shown to arise for certain Fresnel masks and degrade the performance of reconstruction. Extensive numerical experiments are performed to explore the general features of a well-performing mask, the optimal value of q and the robustness with respect to measurement noise.

Progress in utilization of a mobile laboratory for making storm electricity measurements

NASA Technical Reports Server (NTRS)

Rust, W. David

1988-01-01

A mobile atmospheric science laboratory has been used to intercept and track storms on the Great Plains region of the U.S., with the intention of combining the data obtained with those from Doppler and conventional radars, NASA U-2 aircraft overflights, balloon soundings, and fixed-base storm electricity measurements. The mobile lab has proven to be valuable in the gathering of ground truth verifications for the two commercially operated lightning ground-strike locating systems. Data acquisition has recently been expanded by means of mobile ballooning before and during storms.

Context-Aware Mobile Collaborative Systems: Conceptual Modeling and Case Study

PubMed Central

Benítez-Guerrero, Edgard; Mezura-Godoy, Carmen; Montané-Jiménez, Luis G.

2012-01-01

A Mobile Collaborative System (MCOS) enable the cooperation of the members of a team to achieve a common goal by using a combination of mobile and fixed technologies. MCOS can be enhanced if the context of the group of users is considered in the execution of activities. This paper proposes a novel model for Context-Aware Mobile COllaborative Systems (CAMCOS) and a functional architecture based on that model. In order to validate both the model and the architecture, a prototype system in the tourism domain was implemented and evaluated. PMID:23202007

Crustal dynamics project data analysis, 1987. Volume 2: Mobile VLBI geodetic results, 1982-1986

NASA Technical Reports Server (NTRS)

Ma, C.; Ryan, J. W.

1987-01-01

The Goddard VLBI group reports the results of analyzing 101 Mark III data sets acquired from mobile observing sites through the end of 1986 and available to the Crustal Dynamics Project. The fixed VLBI observations at Hat Creek, Ft. Davis, Mojave, and OVRO are included as they participate heavily in the mobile schedules. One large solution GLB171 was used to obtain baseline length and transverse evolutions. Radio source positions were estimated globally, while nutation offsets were estimated from each data set. The results include 28 mobile sites.

Transient Combustion in Granular Propellant Beds. Part I. Theoretical Modeling and Numerical Solution of Transient Combustion Processes in Mobile Granular Propellant Beds

DTIC Science & Technology

1977-08-01

TR~ANSIENT COMBUSTION PROCESSES IN MOBILE GRANULAR PROPELLANT BEDS Prqprid by The Pennsylvania Stats UnIversiV 197 Dopartme of Nmchanica! EngwineerIng...the ignition and flame spreadinb prc-eases by assuming that the granular propillents are fixed in space; and 3) modeling cf mobile granular beds so...through an aggrtgate of mobile "’actin&, partic~vi. The diffevewsoa Wi derivation of conservation equa~tions betvewu our approacit md this -f a Aivorain

CCITT (International Telegraph Consultative Committee) Study Groups XI and XVIII Draft Recommendations for ISDN (Integrated Services Digital Networks), November 8-December 2, 1983.

DTIC Science & Technology

1983-12-01

national gateway closest to an MCI interconnection point would be chosen.) Another significant principle is that mobile users area to be addresses the...duplication with E.16n. It was agreed that, from an addressing viewpoint, mobile subscribers are .. like fixed subscribers; i.e., mobile subscribers have TEs...reference points S and T, NTl, and may have NT2. Therefore, an ISDN number has the same ability to unambiguously identify points in mobile subscriber

Prevalence of bovine milk pathogens in Azorean pastures: mobile versus fixed milking machines.

PubMed

Azevedo, C; Pacheco, D; Soares, L; Moitoso, M; Maldonado, J; Guix, R; Simões, J

2016-01-01

The aims of the present study were (1) to evaluate the influence of using mobile (n=47) or fixed (n=45) milking machines in Azorean herds on the apparent prevalence of several milk pathogens in bulk tank milk (BTM) and (2) to determine whether separated subclinical mastitic cows can serve, in real time, as predictors of milk pathogen prevalence for the remaining animals at the herd level. The use of a mobile or fixed milking machine influenced (P≤0.05) the prevalence of Staphylococcus aureus (72.3 per cent; n=34 v 51.1 per cent; n=23, respectively) and Klebsiella species (46.8 per cent; n=22 v 26.7 per cent; n=12, respectively). S aureus (95 per cent CI OR 1.1 to 6.0) and Klebsiella species (95 per cent CI OR 1.0 to 5.8) were 2.5 times more likely to increase in the BTM of herds using mobile milking machines. The prevalence of coagulase-negative staphylococci (100 per cent; n=92), Escherichia coli (75.0 per cent), Corynebacterium bovis (57.6 per cent), Enterococcus species (55.4 per cent), Streptococcus dysgalactiae (51.1 per cent), Streptococcus uberis (41.3 per cent), Actinomyces pyogenes or Peptostreptococcus indolicus (41.3 per cent) and Streptococcus agalactiae (32.6 per cent) in BTM remained similar among the herds. κ coefficients were always <0.70, indicating intra-herd disagreement of the prevalence of milk pathogens between BTM and separated milking cows. Milking hygiene should be improved in pastures, focusing specifically on herds that use a mobile milking machine. The segregated cows at milking time are not good predictors of milk pathogens in BTM.

Introduction of a new mobile-bearing total knee prosthesis: minimum three year follow-up of an RCT comparing it with a fixed-bearing device.

PubMed

Beard, D J; Pandit, H; Price, A J; Butler-Manuel, P A; Dodd, C A F; Murray, D W; Goodfellow, J W

2007-12-01

As part of the step-wise validation of a new prosthesis (TMK), we previously published the 1 year results of a randomised controlled trial in patients undergoing bilateral knee replacement [Price A., Rees J., Beard D., Juszczak E. et al. A mobile-bearing total knee prosthesis compared with a fixed-bearing prosthesis. JBJS B 2003;85-B-1:62-7.]. Forty patients had the new mobile-bearing prosthesis implanted in one knee and an established fixed-bearing device in the other (AGC). We now report the 3 year status of these patients and, in addition, review a separate multi-centre cohort of 172 patients who had undergone unilateral arthroplasty with the TMK. No significant differences were found in outcome (American Knee Society Score and Oxford Knee Score) between the two prostheses. The greater incidence of "clicking" in the mobile-bearing knee, reported in the previous review, persisted (TMK=48%, AGC=30%). The presence of this mechanical noise was found to have no relationship with outcome in either of the prostheses. The unilateral cohort study showed an acceptable complication rate for the new prosthesis, although some patients reported subjective instability. The method of controlled introduction of the TMK, of which this constitutes a further step, has allowed us to assess the significance of a reported problem (clicking) and to provide scientific data from which other surgeons can decide about use of the implant.

47 CFR 90.733 - Permissible operations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... benchmark for the construction of its land mobile system base stations as prescribed in § 90.725(a); and (2... first meet the requirement to construct its land mobile base station and place it in operation, or... chapter. (f) A Phase I non-nationwide licensee operating a paging base station, or a fixed station...

From Sci-Fi to Reality--Mobile Robots Get the Job Done

ERIC Educational Resources Information Center

Roman, Harry T.

2006-01-01

Robots are simply computers that can interact with their environment. Some are fixed in place in industrial assembly plants for cars, appliances, micro electronic circuitry, and pharmaceuticals. Another important category of robots is the mobiles, machines that can be driven to the workplace, often designed for hazardous duty operation or…

Crustal dynamics project observing plan for highly mobile systems 1981 - 1986

NASA Technical Reports Server (NTRS)

Frey, H.

1980-01-01

Measurement of crustal motion in the western United States and other tectonically active regions makes use of fixed, movable and highly mobile satellite laser ranging and very long baseline interferometry systems. Measurement of the rotational dynamics of the Earth as well as regional deformation and plate motion are discussed.

46 CFR 110.10-1 - Incorporation by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

...; 111.105-40; 113.05-7; and (2) Rules for Building and Classing Mobile Offshore Drilling Units, Part 4...-1; (31) IEC 61363-1 Electrical Installations of Ships and Mobile and Fixed Offshore Units—Part 1.... Box 12277, Research Triangle Park, NC 27709: (1) RP 12.6, Wiring Practices for Hazardous (Classified...

High Power Microwave Tube Reliability Study

DTIC Science & Technology

1976-08-01

Factors . . . . . ................ 67 1. Environmental Factors . . . . . . . . . a. Ground Fixed ...... .......... 67 b. Ground Mobile ...including cube structure and operating parameters as factors in the models but also environment and aplication . Initially, the tubes to be included in...instLllations. Mobile ground based and seagoing systems have minimum restrictions, spacecraft systems the maximum and airborne system Y 6 .*.. restrictionts

Anomaly Detection Techniques for Ad Hoc Networks

ERIC Educational Resources Information Center

Cai, Chaoli

2009-01-01

Anomaly detection is an important and indispensable aspect of any computer security mechanism. Ad hoc and mobile networks consist of a number of peer mobile nodes that are capable of communicating with each other absent a fixed infrastructure. Arbitrary node movements and lack of centralized control make them vulnerable to a wide variety of…

Design of a novel wheeled tensegrity robot: a comparison of tensegrity concepts and a prototype for travelling air ducts.

PubMed

Carreño, Francisco; Post, Mark A

2018-01-01

Efforts in the research of tensegrity structures applied to mobile robots have recently been focused on a purely tensegrity solution to all design requirements. Locomotion systems based on tensegrity structures are currently slow and complex to control. Although wheeled locomotion provides better efficiency over distances there is no literature available on the value of wheeled methods with respect to tensegrity designs, nor on how to transition from a tensegrity structure to a fixed structure in mobile robotics. This paper is the first part of a larger study that aims to combine the flexibility, light weight, and strength of a tensegrity structure with the efficiency and simple control of a wheeled locomotion system. It focuses on comparing different types of tensegrity structure for applicability to a mobile robot, and experimentally finding an appropriate transitional region from a tensegrity structure to a conventional fixed structure on mobile robots. It applies this transitional structure to what is, to the authors' knowledge, the design of the world's first wheeled tensegrity robot that has been designed with the goal of traversing air ducts.

VHF Ranging and Position Fixing Experiment Using ATS Satellites: Final Report on Phases 1 and 2, 25 November 1968 - 1 May 1971

NASA Technical Reports Server (NTRS)

1971-01-01

The testing program with the ATS-1 and ATS-3 spacecraft showed that geostationary satellites can provide superior communications and position surveillance for mobile craft. Inexpensive modifications to conventional mobile communications equipment aboard the craft can provide reliable, high quality voice and digital communications with distant ground stations and other vehicles, and automatic surveillance of the positions of all the craft by a ground facility. The tests also demonstrated the location and automatic readout of remote data collection platforms. Frequency modulation signals with the narrow audio and radio frequency bandwidths of terrestrial mobile radio communications were relayed through the VHF transponders of the geostationary satellites. The voice and digital communications were far superior in reliability and quality to long-distance mobile communications by other means. It was shown that one satellite can provide nearly uniform high quality performance over approximately one-third of the earth's surface. Position fixes by range measurement from the two satellites were accurate to approximately one nautical mile, except near the equator and the poles.

Estimation of coefficient of rolling friction by the evolvent pendulum method

NASA Astrophysics Data System (ADS)

Alaci, S.; Ciornei, F. C.; Ciogole, A.; Ciornei, M. C.

2017-05-01

The paper presents a method for finding the coefficient of rolling friction using an evolvent pendulum. The pendulum consists in a fixed cylindrical body and a mobile body presenting a plane surface in contact with a cylindrical surface. The mobile body is placed over the fixed one in an equilibrium state; after applying a small impulse, the mobile body oscillates. The motion of the body is video recorded and afterwards the movie is analyzed by frames and the decrease with time of angular amplitude of the pendulum is found. The equation of motion is established for oscillations of the mobile body. The equation of motion, differential nonlinear, is integrated by Runge-Kutta method. Imposing the same damping both to model’s solution and to theoretical model, the value of coefficient of rolling friction is obtained. The last part of the paper presents results for actual pairs of materials. The main advantage of the method is the fact that the dimensions of contact regions are small, of order a few millimeters, and thus is substantially reduced the possibility of variation of mechanical characteristic for the two surfaces.

47 CFR 90.475 - Operation of internal transmitter control systems in specially equipped systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... systems involving fixed systems whose base stations are controlled by such systems may automatically access these base stations through the microwave or operational fixed systems from positions in the PSTN, so long as the base stations and mobile units meet the requirements of § 90.483 and if a separate...

Differential-Drive Mobile Robot Control Design based-on Linear Feedback Control Law

NASA Astrophysics Data System (ADS)

Nurmaini, Siti; Dewi, Kemala; Tutuko, Bambang

2017-04-01

This paper deals with the problem of how to control differential driven mobile robot with simple control law. When mobile robot moves from one position to another to achieve a position destination, it always produce some errors. Therefore, a mobile robot requires a certain control law to drive the robot’s movement to the position destination with a smallest possible error. In this paper, in order to reduce position error, a linear feedback control is proposed with pole placement approach to regulate the polynoms desired. The presented work leads to an improved understanding of differential-drive mobile robot (DDMR)-based kinematics equation, which will assist to design of suitable controllers for DDMR movement. The result show by using the linier feedback control method with pole placement approach the position error is reduced and fast convergence is achieved.

A convergent model for distributed processing of Big Sensor Data in urban engineering networks

NASA Astrophysics Data System (ADS)

Parygin, D. S.; Finogeev, A. G.; Kamaev, V. A.; Finogeev, A. A.; Gnedkova, E. P.; Tyukov, A. P.

2017-01-01

The problems of development and research of a convergent model of the grid, cloud, fog and mobile computing for analytical Big Sensor Data processing are reviewed. The model is meant to create monitoring systems of spatially distributed objects of urban engineering networks and processes. The proposed approach is the convergence model of the distributed data processing organization. The fog computing model is used for the processing and aggregation of sensor data at the network nodes and/or industrial controllers. The program agents are loaded to perform computing tasks for the primary processing and data aggregation. The grid and the cloud computing models are used for integral indicators mining and accumulating. A computing cluster has a three-tier architecture, which includes the main server at the first level, a cluster of SCADA system servers at the second level, a lot of GPU video cards with the support for the Compute Unified Device Architecture at the third level. The mobile computing model is applied to visualize the results of intellectual analysis with the elements of augmented reality and geo-information technologies. The integrated indicators are transferred to the data center for accumulation in a multidimensional storage for the purpose of data mining and knowledge gaining.

Exponential stability preservation in semi-discretisations of BAM networks with nonlinear impulses

NASA Astrophysics Data System (ADS)

Mohamad, Sannay; Gopalsamy, K.

2009-01-01

This paper demonstrates the reliability of a discrete-time analogue in preserving the exponential convergence of a bidirectional associative memory (BAM) network that is subject to nonlinear impulses. The analogue derived from a semi-discretisation technique with the value of the time-step fixed is treated as a discrete-time dynamical system while its exponential convergence towards an equilibrium state is studied. Thereby, a family of sufficiency conditions governing the network parameters and the impulse magnitude and frequency is obtained for the convergence. As special cases, one can obtain from our results, those corresponding to the non-impulsive discrete-time BAM networks and also those corresponding to continuous-time (impulsive and non-impulsive) systems. A relation between the Lyapunov exponent of the non-impulsive system and that of the impulsive system involving the size of the impulses and the inter-impulse intervals is obtained.

Configuration complexity assessment of convergent supply chain systems

NASA Astrophysics Data System (ADS)

Modrak, Vladimir; Marton, David

2014-07-01

System designers usually generate alternative configurations of supply chains (SCs) by varying especially fixed assets to satisfy a desired production scope and rate. Such alternatives often vary in associated costs and other facets including degrees of complexity. Hence, a measure of configuration complexity can be a tool for comparison and decision-making. This paper presents three approaches to assessment of configuration complexity and their applications to designing convergent SC systems. Presented approaches are conceptually distinct ways of measuring structural complexity parameters based on different preconditions and circumstances of assembly systems which are typical representatives of convergent SCs. There are applied two similar approaches based on different preconditions that are related to demand shares. Third approach does not consider any special condition relating to character of final product demand. Subsequently, we propose a framework for modeling of assembly SC models, which are dividing to classes.

Fourier phase retrieval with a single mask by Douglas-Rachford algorithms.

PubMed

Chen, Pengwen; Fannjiang, Albert

2018-05-01

The Fourier-domain Douglas-Rachford (FDR) algorithm is analyzed for phase retrieval with a single random mask. Since the uniqueness of phase retrieval solution requires more than a single oversampled coded diffraction pattern, the extra information is imposed in either of the following forms: 1) the sector condition on the object; 2) another oversampled diffraction pattern, coded or uncoded. For both settings, the uniqueness of projected fixed point is proved and for setting 2) the local, geometric convergence is derived with a rate given by a spectral gap condition. Numerical experiments demonstrate global, power-law convergence of FDR from arbitrary initialization for both settings as well as for 3 or more coded diffraction patterns without oversampling. In practice, the geometric convergence can be recovered from the power-law regime by a simple projection trick, resulting in highly accurate reconstruction from generic initialization.

Electron- and positron-molecule scattering: development of the molecular convergent close-coupling method

NASA Astrophysics Data System (ADS)

Zammit, Mark C.; Fursa, Dmitry V.; Savage, Jeremy S.; Bray, Igor

2017-06-01

Starting from first principles, this tutorial describes the development of the adiabatic-nuclei convergent close-coupling (CCC) method and its application to electron and (single-centre) positron scattering from diatomic molecules. We give full details of the single-centre expansion CCC method, namely the formulation of the molecular target structure; solving the momentum-space coupled-channel Lippmann-Schwinger equation; deriving adiabatic-nuclei cross sections and calculating V-matrix elements. Selected results are presented for electron and positron scattering from molecular hydrogen H2 and electron scattering from the vibrationally excited molecular hydrogen ion {{{H}}}2+ and its isotopologues (D2 +, {{{T}}}2+, HD+, HT+ and TD+). Convergence in both the close-coupling (target state) and projectile partial-wave expansions of fixed-nuclei electron- and positron-molecule scattering calculations is demonstrated over a broad energy-range and discussed in detail. In general, the CCC results are in good agreement with experiments.

Convergent Polishing: A Simple, Rapid, Full Aperture Polishing Process of High Quality Optical Flats & Spheres

PubMed Central

Suratwala, Tayyab; Steele, Rusty; Feit, Michael; Dylla-Spears, Rebecca; Desjardin, Richard; Mason, Dan; Wong, Lana; Geraghty, Paul; Miller, Phil; Shen, Nan

2014-01-01

Convergent Polishing is a novel polishing system and method for finishing flat and spherical glass optics in which a workpiece, independent of its initial shape (i.e., surface figure), will converge to final surface figure with excellent surface quality under a fixed, unchanging set of polishing parameters in a single polishing iteration. In contrast, conventional full aperture polishing methods require multiple, often long, iterative cycles involving polishing, metrology and process changes to achieve the desired surface figure. The Convergent Polishing process is based on the concept of workpiece-lap height mismatch resulting in pressure differential that decreases with removal and results in the workpiece converging to the shape of the lap. The successful implementation of the Convergent Polishing process is a result of the combination of a number of technologies to remove all sources of non-uniform spatial material removal (except for workpiece-lap mismatch) for surface figure convergence and to reduce the number of rogue particles in the system for low scratch densities and low roughness. The Convergent Polishing process has been demonstrated for the fabrication of both flats and spheres of various shapes, sizes, and aspect ratios on various glass materials. The practical impact is that high quality optical components can be fabricated more rapidly, more repeatedly, with less metrology, and with less labor, resulting in lower unit costs. In this study, the Convergent Polishing protocol is specifically described for fabricating 26.5 cm square fused silica flats from a fine ground surface to a polished ~λ/2 surface figure after polishing 4 hr per surface on a 81 cm diameter polisher. PMID:25489745

Numerical Optimization of converging diverging miniature cavitating nozzles

NASA Astrophysics Data System (ADS)

Chavan, Kanchan; Bhingole, B.; Raut, J.; Pandit, A. B.

2015-12-01

The work focuses on the numerical optimization of converging diverging cavitating nozzles through nozzle dimensions and wall shape. The objective is to develop design rules for the geometry of cavitating nozzles for desired end-use. Two main aspects of nozzle design which affects the cavitation have been studied i.e. end dimensions of the geometry (i.e. angle and/or curvature of the inlet, outlet and the throat and the lengths of the converging and diverging sections) and wall curvatures(concave or convex). Angle of convergence at the inlet was found to control the cavity growth whereas angle of divergence of the exit controls the collapse of cavity. CFD simulations were carried out for the straight line converging and diverging sections by varying converging and diverging angles to study its effect on the collapse pressure generated by the cavity. Optimized geometry configurations were obtained on the basis of maximum Cavitational Efficacy Ratio (CER)i.e. cavity collapse pressure generated for a given permanent pressure drop across the system. With increasing capabilities in machining and fabrication, it is possible to exploit the effect of wall curvature to create nozzles with further increase in the CER. Effect of wall curvature has been studied for the straight, concave and convex shapes. Curvature has been varied and effect of concave and convex wall curvatures vis-à-vis straight walls studied for fixed converging and diverging angles.It is concluded that concave converging-diverging nozzles with converging angle of 20° and diverging angle of 5° with the radius of curvature 0.03 m and 0.1530 m respectively gives maximum CER. Preliminary experiments using optimized geometry are indicating similar trends and are currently being carried out. Refinements of the CFD technique using two phase flow simulations are planned.

Exploring experiential value in online mobile gaming adoption.

PubMed

Okazaki, Shintaro

2008-10-01

Despite the growing importance of the online mobile gaming industry, little research has been undertaken to explain why consumers engage in this ubiquitous entertainment. This study attempts to develop an instrument to measure experiential value in online mobile gaming adoption. The proposed scale consists of seven first-order factors of experiential value: intrinsic enjoyment, escapism, efficiency, economic value, visual appeal, perceived novelty, and perceived risklessness. The survey obtained 164 usable responses from Japanese college students. The empirical data fit our first-order model well, indicating a high level of reliability as well as convergent and discriminant validity. The single second-order model also shows an acceptable model fit.

NASA Space Geodesy Program: GSFC data analysis, 1993. VLBI geodetic results 1979 - 1992

NASA Technical Reports Server (NTRS)

Ma, Chopo; Ryan, James W.; Caprette, Douglas S.

1994-01-01

The Goddard VLBI group reports the results of analyzing Mark 3 data sets acquired from 110 fixed and mobile observing sites through the end of 1992 and available to the Space Geodesy Program. Two large solutions were used to obtain site positions, site velocities, baseline evolution for 474 baselines, earth rotation parameters, nutation offsets, and radio source positions. Site velocities are presented in both geocentric Cartesian and topocentric coordinates. Baseline evolution is plotted for the 89 baselines that were observed in 1992 and positions at 1988.0 are presented for all fixed stations and mobile sites. Positions are also presented for quasar radio sources used in the solutions.

A Mobile Sensor Network to Map CO2 in Urban Environments

NASA Astrophysics Data System (ADS)

Lee, J.; Christen, A.; Nesic, Z.; Ketler, R.

2014-12-01

Globally, an estimated 80% of all fuel-based CO2 emissions into the atmosphere are attributable to cities, but there is still a lack of tools to map, visualize and monitor emissions to the scales at which emissions reduction strategies can be implemented - the local and urban scale. Mobile CO2 sensors, such as those attached to taxis and other existing mobile platforms, may be a promising way to observe and map CO2 mixing ratios across heterogenous urban environments with a limited number of sensors. Emerging modular open source technologies, and inexpensive compact sensor components not only enable rapid prototyping and replication, but also are allowing for the miniaturization and mobilization of traditionally fixed sensor networks. We aim to optimize the methods and technologies for monitoring CO2 in cities using a network of CO2 sensors deployable on vehicles and bikes. Our sensor technology is contained in a compact weather-proof case (35.8cm x 27.8cm x 11.8cm), powered independently by battery or by car, and includes the Li-Cor Li-820 infrared gas analyzer (Licor Inc, lincoln, NB, USA), Arduino Mega microcontroller (Arduino CC, Italy) and Adafruit GPS (Adafruit Technologies, NY, USA), and digital air temperature thermometer which measure CO2 mixing ratios (ppm), geolocation and speed, pressure and temperature, respectively at 1-second intervals. With the deployment of our sensor technology, we will determine if such a semi-autonomous mobile approach to monitoring CO2 in cities can determine excess urban CO2 mixing ratios (i.e. the 'urban CO2 dome') when compared to values measured at a fixed, remote background site. We present results from a pilot study in Vancouver, BC, where the a network of our new sensors was deployed both in fixed network and in a mobile campaign and examine the spatial biases of the two methods.

Mobilesat (tm): A world first

NASA Technical Reports Server (NTRS)

Cooper, Paul; Crawley, Linda

1993-01-01

Mobilesat will be the world's first truly mobile satellite telephony service to be offered in the land mobile market. Essentially a car phone which will be offered as a fixed service at a later date, mobilesat will bring circuit switched voice communications to remote and rural areas of Australia. This paper outlines where mobilesat fits as part of Optus, Australia's new telecommunications carrier, and briefly discuss the mobilesat system, its market, and the future of mobile communications in Australia.

The Component Timed-Up-and-Go test: the utility and psychometric properties of using a mobile application to determine prosthetic mobility in people with lower limb amputations.

PubMed

Clemens, Sheila M; Gailey, Robert S; Bennett, Christopher L; Pasquina, Paul F; Kirk-Sanchez, Neva J; Gaunaurd, Ignacio A

2018-03-01

Using a custom mobile application to evaluate the reliability and validity of the Component Timed-Up-and-Go test to assess prosthetic mobility in people with lower limb amputation. Cross-sectional design. National conference for people with limb loss. A total of 118 people with non-vascular cause of lower limb amputation participated. Subjects had a mean age of 48 (±13.7) years and were an average of 10 years post amputation. Of them, 54% ( n = 64) of subjects were male. None. The Component Timed-Up-and-Go was administered using a mobile iPad application, generating a total time to complete the test and five component times capturing each subtask (sit to stand transitions, linear gait, turning) of the standard timed-up-and-go test. The outcome underwent test-retest reliability using intraclass correlation coefficients (ICCs) and convergent validity analyses through correlation with self-report measures of balance and mobility. The Component Timed-Up-and-Go exhibited excellent test-retest reliability with ICCs ranging from .98 to .86 for total and component times. Evidence of discriminative validity resulted from significant differences in mean total times between people with transtibial (10.1 (SD: ±2.3)) and transfemoral (12.76 (SD: ±5.1) amputation, as well as significant differences in all five component times ( P < .05). Convergent validity of the Component Timed-Up-and-Go was demonstrated through moderate correlations with the PLUS-M ( r s  = -.56). The Component Timed-Up-and-Go is a reliable and valid clinical tool for detailed assessment of prosthetic mobility in people with non-vascular lower limb amputation. The iPad application provided a means to easily record data, contributing to clinical utility.

Identification of Mobile Phones Using the Built-In Magnetometers Stimulated by Motion Patterns.

PubMed

Baldini, Gianmarco; Dimc, Franc; Kamnik, Roman; Steri, Gary; Giuliani, Raimondo; Gentile, Claudio

2017-04-06

We investigate the identification of mobile phones through their built-in magnetometers. These electronic components have started to be widely deployed in mass market phones in recent years, and they can be exploited to uniquely identify mobile phones due their physical differences, which appear in the digital output generated by them. This is similar to approaches reported in the literature for other components of the mobile phone, including the digital camera, the microphones or their RF transmission components. In this paper, the identification is performed through an inexpensive device made up of a platform that rotates the mobile phone under test and a fixed magnet positioned on the edge of the rotating platform. When the mobile phone passes in front of the fixed magnet, the built-in magnetometer is stimulated, and its digital output is recorded and analyzed. For each mobile phone, the experiment is repeated over six different days to ensure consistency in the results. A total of 10 phones of different brands and models or of the same model were used in our experiment. The digital output from the magnetometers is synchronized and correlated, and statistical features are extracted to generate a fingerprint of the built-in magnetometer and, consequently, of the mobile phone. A SVM machine learning algorithm is used to classify the mobile phones on the basis of the extracted statistical features. Our results show that inter-model classification (i.e., different models and brands classification) is possible with great accuracy, but intra-model (i.e., phones with different serial numbers and same model) classification is more challenging, the resulting accuracy being just slightly above random choice.

Identification of Mobile Phones Using the Built-In Magnetometers Stimulated by Motion Patterns

PubMed Central

Baldini, Gianmarco; Dimc, Franc; Kamnik, Roman; Steri, Gary; Giuliani, Raimondo; Gentile, Claudio

2017-01-01

We investigate the identification of mobile phones through their built-in magnetometers. These electronic components have started to be widely deployed in mass market phones in recent years, and they can be exploited to uniquely identify mobile phones due their physical differences, which appear in the digital output generated by them. This is similar to approaches reported in the literature for other components of the mobile phone, including the digital camera, the microphones or their RF transmission components. In this paper, the identification is performed through an inexpensive device made up of a platform that rotates the mobile phone under test and a fixed magnet positioned on the edge of the rotating platform. When the mobile phone passes in front of the fixed magnet, the built-in magnetometer is stimulated, and its digital output is recorded and analyzed. For each mobile phone, the experiment is repeated over six different days to ensure consistency in the results. A total of 10 phones of different brands and models or of the same model were used in our experiment. The digital output from the magnetometers is synchronized and correlated, and statistical features are extracted to generate a fingerprint of the built-in magnetometer and, consequently, of the mobile phone. A SVM machine learning algorithm is used to classify the mobile phones on the basis of the extracted statistical features. Our results show that inter-model classification (i.e., different models and brands classification) is possible with great accuracy, but intra-model (i.e., phones with different serial numbers and same model) classification is more challenging, the resulting accuracy being just slightly above random choice. PMID:28383482

Mobile: Letting Go of the Device and Building for Innovation

ERIC Educational Resources Information Center

Davis, Jim; Rocchio, Rosemary A.

2011-01-01

Mobile use of the Internet is on target to surpass fixed use by 2014. Three-fourths of all college/university students have purchased or intend to purchase an Internet-enabled handheld device within the next year. The smartphone market is changing almost monthly. Attempting to manage even just one or a few "devices" is becoming a lost…

Photomat: A Mobile Tool for Aiding in Student Construction of Research Questions and Data Analysis

ERIC Educational Resources Information Center

Shelley, Tia Renee; Dasgupta, Chandan; Silva, Alexandra; Lyons, Leilah; Moher, Tom

2015-01-01

This paper presents a new mobile software tool, PhotoMAT (Photo Management and Analysis Tool), and students' experiences with this tool within a scaffolded curricular unit--Neighborhood Safari. PhotoMAT was designed to support learners' investigations of backyard animal behavior and works with image sets obtained using fixed-position field cameras…

47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

Code of Federal Regulations, 2014 CFR

2014-10-01

... of part 1 of this chapter, in particular § 1.1307(b). (b) For purposes of this section, a mobile device is defined as a transmitting device designed to be used in other than fixed locations and to generally be used in such a way that a separation distance of at least 20 centimeters is normally maintained...

47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

Code of Federal Regulations, 2013 CFR

2013-10-01

... of part 1 of this chapter, in particular § 1.1307(b). (b) For purposes of this section, a mobile device is defined as a transmitting device designed to be used in other than fixed locations and to generally be used in such a way that a separation distance of at least 20 centimeters is normally maintained...

47 CFR 90.763 - EA, Regional and nationwide system operations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... authorized pursuant to § 90.761 may construct and operate any number of land mobile or paging base stations... authorized pursuant to § 90.717(a) may construct and operate any number of land mobile or paging base stations, or fixed stations, anywhere in the Nation, and transmit on any of its authorized channels...

47 CFR 90.763 - EA, Regional and nationwide system operations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... authorized pursuant to § 90.761 may construct and operate any number of land mobile or paging base stations... authorized pursuant to § 90.717(a) may construct and operate any number of land mobile or paging base stations, or fixed stations, anywhere in the Nation, and transmit on any of its authorized channels...

47 CFR 90.763 - EA, Regional and nationwide system operations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... authorized pursuant to § 90.761 may construct and operate any number of land mobile or paging base stations... authorized pursuant to § 90.717(a) may construct and operate any number of land mobile or paging base stations, or fixed stations, anywhere in the Nation, and transmit on any of its authorized channels...

Basins of distinct asymptotic states in the cyclically competing mobile five species game

NASA Astrophysics Data System (ADS)

Kim, Beomseok; Park, Junpyo

2017-10-01

We study the dynamics of cyclic competing mobile five species on spatially extended systems originated from asymmetric initial populations and investigate the basins for the three possible asymptotic states, coexistence of all species, existences of only two independent species, and the extinction. Through extensive numerical simulations, we find a prosperous dependence on initial conditions for species biodiversity. In particular, for fixed given equal densities of two relevant species, we find that only five basins for the existence of two independent species exist and they are spirally entangled for high mobility. A basin of coexistence is outbreaking when the mobility parameter is decreased through a critical value and surrounded by the other five basins. For fixed given equal densities of two independent species, however, we find that basin structures are not spirally entangled. Further, final states of two independent species are totally different. For all possible considerations, the extinction state is not witnessed which is verified by the survival probability. To provide the validity of basin structures from lattice simulations, we analyze the system in mean-field manners. Consequently, results on macroscopic levels are matched to direct lattice simulations for high mobility regimes. These findings provide a good insight into the fundamental issue of the biodiversity among many species than previous cases.

Effect of mobile phone use on metal ion release from fixed orthodontic appliances.

PubMed

Saghiri, Mohammad Ali; Orangi, Jafar; Asatourian, Armen; Mehriar, Peiman; Sheibani, Nader

2015-06-01

The aim of this study was to evaluate the effect of exposure to radiofrequency electromagnetic fields emitted by mobile phones on the level of nickel in saliva. Fifty healthy patients with fixed orthodontic appliances were asked not to use their cell phones for a week, and their saliva samples were taken at the end of the week (control group). The patients recorded their time of mobile phone usage during the next week and returned for a second saliva collection (experimental group). Samples at both times were taken between 8:00 and 10:00 pm, and the nickel levels were measured. Two-tailed paired-samples t test, linear regression, independent t test, and 1-way analysis of variance were used for data analysis. The 2-tailed paired-samples t test showed significant differences between the levels of nickel in the control and experimental groups (t [49] = 9.967; P <0.001). The linear regression test showed a significant relationship between mobile phone usage time and the nickel release (F [1, 48] = 60.263; P <0.001; R(2) = 0.577). Mobile phone usage has a time-dependent influence on the concentration of nickel in the saliva of patients with orthodontic appliances. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Exploring mobility & workplace choice in a flexible office through post-occupancy evaluation.

PubMed

Göçer, Özgür; Göçer, Kenan; Ergöz Karahan, Ebru; İlhan Oygür, Işıl

2018-02-01

Developments in information and communication systems, organisational structure and the nature of work have contributed to the restructuring of work environments. In these new types of work environments, employees do not have assigned workplaces. This arrangement helps organisations to minimise rent costs and increase employee interaction and knowledge exchange through mobility. This post-occupancy evaluation (POE) study focuses on a flexible office in a Gold Leadership in Energy and Environmental Design-certified building in Istanbul. An integrated qualitative and quantitative POE technique with occupancy tracking via barcode scanning and instant surveying has been introduced. Using this unique approach, we examined the directives/drivers in workplace choice and mobility from different perspectives. The aggregated data was used to discern work-related consequences such as flexibility, workplace choice, work and indoor environment satisfaction, place attachment and identity. The results show that employees who have a conventional working culture develop a new working style: 'fixed-flexible working'. Practitioner Summary: This paper introduces a new POE approach for flexible offices based on occupancy tracking through barcode scanning to explore workplace choice and mobility. More than half (52.1%) of the participants have tended to choose the same desk every day. However, the satisfaction level of the 'mobile' employees was higher than that of the 'fixed flexible' employees.

Bachelor's Degree Productivity X-Inefficiency: The Role of State Higher Education Policy

ERIC Educational Resources Information Center

Titus, Marvin A.

2010-01-01

Using stochastic frontier analysis and dynamic fixed-effects panel modeling, this study examines how changes in the x-inefficiency of bachelor's degree production are influenced by changes in state higher education policy. The findings from this research show that increases in need-based state financial aid help to mitigate the convergence among…

Convergence

NASA Astrophysics Data System (ADS)

Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.

2005-01-01

Call for Papers: Convergence

Guest Editors: Thomas E. Darcie, University of Victoria Robert Doverspike, AT&T Martin Zirngibl, Lucent Technologies

Coordinating Associate Editor: Steven K. Korotky, Lucent Technologies

• Architecture, design and performance of optical wide-area-network (WAN), metro, and access networks
• Integration strategies for multiservice transport platforms
• Access methods that bridge traditional and emerging services
• Network signaling and control methodologies
• All-optical packet routing and switching techniques

Manuscript Submission

Dynamically analyzing cell interactions in biological environments using multiagent social learning framework.

PubMed

Zhang, Chengwei; Li, Xiaohong; Li, Shuxin; Feng, Zhiyong

2017-09-20

Biological environment is uncertain and its dynamic is similar to the multiagent environment, thus the research results of the multiagent system area can provide valuable insights to the understanding of biology and are of great significance for the study of biology. Learning in a multiagent environment is highly dynamic since the environment is not stationary anymore and each agent's behavior changes adaptively in response to other coexisting learners, and vice versa. The dynamics becomes more unpredictable when we move from fixed-agent interaction environments to multiagent social learning framework. Analytical understanding of the underlying dynamics is important and challenging. In this work, we present a social learning framework with homogeneous learners (e.g., Policy Hill Climbing (PHC) learners), and model the behavior of players in the social learning framework as a hybrid dynamical system. By analyzing the dynamical system, we obtain some conditions about convergence or non-convergence. We experimentally verify the predictive power of our model using a number of representative games. Experimental results confirm the theoretical analysis. Under multiagent social learning framework, we modeled the behavior of agent in biologic environment, and theoretically analyzed the dynamics of the model. We present some sufficient conditions about convergence or non-convergence and prove them theoretically. It can be used to predict the convergence of the system.

Epidemic spreading induced by diversity of agents' mobility.

PubMed

Zhou, Jie; Chung, Ning Ning; Chew, Lock Yue; Lai, Choy Heng

2012-08-01

In this paper, we study the impact of the preference of an individual for public transport on the spread of infectious disease, through a quantity known as the public mobility. Our theoretical and numerical results based on a constructed model reveal that if the average public mobility of the agents is fixed, an increase in the diversity of the agents' public mobility reduces the epidemic threshold, beyond which an enhancement in the rate of infection is observed. Our findings provide an approach to improve the resistance of a society against infectious disease, while preserving the utilization rate of the public transportation system.

``Just Another Distribution Channel?''

NASA Astrophysics Data System (ADS)

Lemstra, Wolter; de Leeuw, Gerd-Jan; van de Kar, Els; Brand, Paul

The telecommunications-centric business model of mobile operators is under attack due to technological convergence in the communication and content industries. This has resulted in a plethora of academic contributions on the design of new business models and service platform architectures. However, a discussion of the challenges that operators are facing in adopting these models is lacking. We assess these challenges by considering the mobile network as part of the value system of the content industry. We will argue that from the perspective of a content provider the mobile network is ‘just another’ distribution channel. Strategic options available for the mobile communication operators are to deliver an excellent distribution channel for content delivery or to move upwards in the value chain by becoming a content aggregator. To become a mobile content aggregator operators will have to develop or acquire complementary resources and capabilities. Whether this strategic option is sustainable remains open.

Efficient Mobility Summit: Transportation and the Future of Dynamic Mobility Systems

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

2015-12-01

On October 27, 2015, The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) brought together local and national thought leaders to discuss the convergence of connectivity, vehicle automation, and transportation infrastructure investments at the Future Energy Efficient Mobility Workshop. The half-day workshop was held in conjunction with the Colorado Department of Transportation's (CDOT) Transportation Matters Summit and featured four panel sessions that showcased perspectives on efficient mobility from federal and state agencies, automakers and their suppliers, transportation data providers, and freight companies. This summary provides highlights from the meeting's exchanges of ideas and existing applications. Transportation's (CDOT) Transportation Mattersmore » Summit and featured four panel sessions that showcased perspectives on efficient mobility from federal and state agencies, automakers and their suppliers, transportation data providers, and freight companies. This summary provides highlights from the meeting's exchanges of ideas and existing applications.« less

Free-time and fixed end-point optimal control theory in dissipative media: application to entanglement generation and maintenance.

PubMed

Mishima, K; Yamashita, K

2009-07-07

We develop monotonically convergent free-time and fixed end-point optimal control theory (OCT) in the density-matrix representation to deal with quantum systems showing dissipation. Our theory is more general and flexible for tailoring optimal laser pulses in order to control quantum dynamics with dissipation than the conventional fixed-time and fixed end-point OCT in that the optimal temporal duration of laser pulses can also be optimized exactly. To show the usefulness of our theory, it is applied to the generation and maintenance of the vibrational entanglement of carbon monoxide adsorbed on the copper (100) surface, CO/Cu(100). We demonstrate the numerical results and clarify how to combat vibrational decoherence as much as possible by the tailored shapes of the optimal laser pulses. It is expected that our theory will be general enough to be applied to a variety of dissipative quantum dynamics systems because the decoherence is one of the quantum phenomena sensitive to the temporal duration of the quantum dynamics.

A Novel Riemannian Metric Based on Riemannian Structure and Scaling Information for Fixed Low-Rank Matrix Completion.

PubMed

Mao, Shasha; Xiong, Lin; Jiao, Licheng; Feng, Tian; Yeung, Sai-Kit

2017-05-01

Riemannian optimization has been widely used to deal with the fixed low-rank matrix completion problem, and Riemannian metric is a crucial factor of obtaining the search direction in Riemannian optimization. This paper proposes a new Riemannian metric via simultaneously considering the Riemannian geometry structure and the scaling information, which is smoothly varying and invariant along the equivalence class. The proposed metric can make a tradeoff between the Riemannian geometry structure and the scaling information effectively. Essentially, it can be viewed as a generalization of some existing metrics. Based on the proposed Riemanian metric, we also design a Riemannian nonlinear conjugate gradient algorithm, which can efficiently solve the fixed low-rank matrix completion problem. By experimenting on the fixed low-rank matrix completion, collaborative filtering, and image and video recovery, it illustrates that the proposed method is superior to the state-of-the-art methods on the convergence efficiency and the numerical performance.

Assessment of the Effectiveness and Effects of Land Disposal Methodologies of Waste Water Management.

DTIC Science & Technology

1972-01-14

conditions that inhibit nitrification should be avoided. Potassium: Potassium is a very mobile and dynamic element in both soil and plant systems. It...deposits from aerial sources. I i conclusion, lead is fixed in soils and not readily mobilized . Soils should retain several hundred mg/i against leaching...is one of these. These are relatively large molecules and are strongly retained by river muds, etc. They can be expected to be of very limited mobility

Some estimation formulae for continuous time-invariant linear systems

NASA Technical Reports Server (NTRS)

Bierman, G. J.; Sidhu, G. S.

1975-01-01

In this brief paper we examine a Riccati equation decomposition due to Reid and Lainiotis and apply the result to the continuous time-invariant linear filtering problem. Exploitation of the time-invariant structure leads to integration-free covariance recursions which are of use in covariance analyses and in filter implementations. A super-linearly convergent iterative solution to the algebraic Riccati equation (ARE) is developed. The resulting algorithm, arranged in a square-root form, is thought to be numerically stable and competitive with other ARE solution methods. Certain covariance relations that are relevant to the fixed-point and fixed-lag smoothing problems are also discussed.

Deep Soil Recharge in Arid and Semi-Arid Regions: New Evidences in MU-US Sandy Land of China

NASA Astrophysics Data System (ADS)

Cheng, Y.; Yang, W.; Zhan, H.

2017-12-01

Precipitation induced recharge is an important source of groundwater budget but it is very difficult to quantify in arid and semiarid regions. In this study, a newly invented lysimeter was used to monitor deep soil recharge (DSR) under 200 cm depth in MU-US sandy land in western China under three kinds of landforms (mobile dune, semi-fixed dune, and fixed dune). We found that the annual DSRs in such three different kinds of landforms varied significantly. Specifically, the annual DSRs were 224.1 mm (50.5% of the annual precipitation), 71.1 mm (50.5% of the annual precipitation), and 1.3 mm (0.3% of the annual precipitation) in mobile dune, semi-fixed dune, and fixed dune, respectively. We also found that vegetation coverage and precipitation pattern significantly affected DSR. A 24-hr precipitation event with the precipitation amount greater than 8 mm was able to infiltrate soil deeper than 200 cm and contributed to ground water recharge directly. Vegetation was a dominant factor influencing infiltration in the fixed sand dune. Our research revealed that precipitation induced DSR in arid and semi-arid regions was a complex process that required long-term monitoring and innovative system analysis of interrelated factors such as precipitation strength and pattern, meteorological parameters, and dynamic soil moisture. Key words: Precipitation pattern, sand dune groundwater, deep soil recharge, infiltration.

NASA Space Geodesy Program: GSFC data analysis, 1992. Crustal Dynamics Project VLBI geodetic results, 1979 - 1991

NASA Technical Reports Server (NTRS)

Ryan, J. W.; Ma, C.; Caprette, D. S.

1993-01-01

The Goddard VLBI group reports the results of analyzing 1648 Mark 3 data sets acquired from fixed and mobile observing sites through the end of 1991, and available to the Crustal Dynamics Project. Two large solutions were used to obtain Earth rotation parameters, nutation offsets, radio source positions, site positions, site velocities, and baseline evolution. Site positions are tabulated on a yearly basis for 1979 to 1995, inclusive. Site velocities are presented in both geocentric Cartesian and topocentric coordinates. Baseline evolution is plotted for 200 baselines, and individual length determinations are presented for an additional 356 baselines. This report includes 155 quasar radio sources, 96 fixed stations and mobile sites, and 556 baselines.

An integrated voice and data multiple-access scheme for a land-mobile satellite system

NASA Technical Reports Server (NTRS)

Li, V. O. K.; Yan, T.-Y.

1984-01-01

An analytical study is performed of the satellite requirements for a land mobile satellite system (LMSS). The spacecraft (MSAT-X) would be in GEO and would be compatible with multiple access by mobile radios and antennas and fixed stations. The FCC has received a petition from NASA to reserve the 821-825 and 866-870 MHz frequencies for the LMSS, while communications with fixed earth stations would be in the Ku band. MSAT-X transponders would alter the frequencies of signal and do no processing in the original configuration considered. Channel use would be governed by an integrated demand-assigned, multiple access protocol, which would divide channels into reservation and information channels, governed by a network management center. Further analyses will cover tradeoffs between data and voice users, probability of blocking, and the performance impacts of on-board switching and variable bandwidth assignment. Initial calculations indicate that a large traffic volume can be handled with acceptable delays and voice blocking probabilities.

An integrated voice and data multiple-access scheme for a land-mobile satellite system

NASA Astrophysics Data System (ADS)

Li, V. O. K.; Yan, T.-Y.

1984-11-01

An analytical study is performed of the satellite requirements for a land mobile satellite system (LMSS). The spacecraft (MSAT-X) would be in GEO and would be compatible with multiple access by mobile radios and antennas and fixed stations. The FCC has received a petition from NASA to reserve the 821-825 and 866-870 MHz frequencies for the LMSS, while communications with fixed earth stations would be in the Ku band. MSAT-X transponders would alter the frequencies of signal and do no processing in the original configuration considered. Channel use would be governed by an integrated demand-assigned, multiple access protocol, which would divide channels into reservation and information channels, governed by a network management center. Further analyses will cover tradeoffs between data and voice users, probability of blocking, and the performance impacts of on-board switching and variable bandwidth assignment. Initial calculations indicate that a large traffic volume can be handled with acceptable delays and voice blocking probabilities.

Considerations for Improving the Capacity and Performance of AeroMACS

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Kamali, Behnam; Apaza, Rafael D.; Wilson, Jeffrey D.; Dimond, Robert P.

2014-01-01

The Aeronautical Mobile Airport Communications System (AeroMACS) has progressed from concept through prototype development, testing, and standards development and is now poised for the first operational deployments at nine US airports by the Federal Aviation Administration. These initial deployments will support fixed applications. Mobile applications providing connectivity to and from aircraft and ground-based vehicles on the airport surface will occur at some point in the future. Given that many fixed applications are possible for AeroMACS, it is necessary to now consider whether the existing capacity of AeroMACS will be reached even before the mobile applications are ready to be added, since AeroMACS is constrained by both available bandwidth and transmit power limitations. This paper describes some concepts that may be applied to improve the future capacity of AeroMACS, with a particular emphasis on gains that can be derived from the addition of IEEE 802.16j multihop relays to the AeroMACS standard, where a significant analysis effort has been undertaken.

Challenges with Deploying and Integrating Environmental Control and Life Support Functions in a Lunar Architecture with High Degrees of Mobility

NASA Technical Reports Server (NTRS)

Bagdigian, Robert M.

2009-01-01

Visions of lunar outposts often depict a collection of fixed elements such as pressurized habitats, in and around which human inhabitants spend the large majority of their surface stay time. In such an outpost, an efficient deployment of environmental control and life support equipment can be achieved by centralizing certain functions within one or a minimum number of habitable elements and relying on the exchange of gases and liquids between elements via atmosphere ventilation and plumbed interfaces. However, a rigidly fixed outpost can constrain the degree to which the total lunar landscape can be explored. The capability to enable widespread access across the landscape makes a lunar architecture with a high degree of surface mobility attractive. Such mobility presents unique challenges to the efficient deployment of environmental control and life support functions in multiple elements that may for long periods of time be operated independently. This paper describes some of those anticipated challenges.

Mobility management techniques for the next-generation wireless networks

NASA Astrophysics Data System (ADS)

Sun, Junzhao; Howie, Douglas P.; Sauvola, Jaakko J.

2001-10-01

The tremendous demands from social market are pushing the booming development of mobile communications faster than ever before, leading to plenty of new advanced techniques emerging. With the converging of mobile and wireless communications with Internet services, the boundary between mobile personal telecommunications and wireless computer networks is disappearing. Wireless networks of the next generation need the support of all the advances on new architectures, standards, and protocols. Mobility management is an important issue in the area of mobile communications, which can be best solved at the network layer. One of the key features of the next generation wireless networks is all-IP infrastructure. This paper discusses the mobility management schemes for the next generation mobile networks through extending IP's functions with mobility support. A global hierarchical framework model for the mobility management of wireless networks is presented, in which the mobility management is divided into two complementary tasks: macro mobility and micro mobility. As the macro mobility solution, a basic principle of Mobile IP is introduced, together with the optimal schemes and the advances in IPv6. The disadvantages of the Mobile IP on solving the micro mobility problem are analyzed, on the basis of which three main proposals are discussed as the micro mobility solutions for mobile communications, including Hierarchical Mobile IP (HMIP), Cellular IP, and Handoff-Aware Wireless Access Internet Infrastructure (HAWAII). A unified model is also described in which the different micro mobility solutions can coexist simultaneously in mobile networks.

Professional and spatial mobility of osteopathic physicians.

PubMed

Hassinger, E W; Gill, L S; Hobbs, D J; Hageman, R L

1979-12-01

The study examines changes in location of osteopathic and medical doctors in a 20-county area of rural Missouri over a 14-year period. Losses of osteopathic physicians were greater than medical doctors. However, there was a convergence over the 14-year period in background characteristics of the two types of physicians. The finding of greater spatial mobility of DOs is placed in the context of professional mobility of osteopathy. It is also argued that as practice opportunities for DOs increase, background factors associated with early socialization become more influential in choice of practice sites. The relationship of practice opportunities to choice of practice sites can be extended to foreign medical school graduates and "new health practitioners."

SWARMS: Scalable sWarms of Autonomous Robots and Mobile Sensors

DTIC Science & Technology

2013-03-18

Pasqualetti, Antonio Franchi , Francesco Bullo. On optimal cooperative patrolling, 2010 49th IEEE Conference on Decision and Control (CDC). 2010/12/15 00...exhibits “ global stability” Provided a complete convergence proof for the adaptive version of the range only station keeping problem. Graph Theoretic

Mobile Devices and Apps as Scaffolds to Science Learning in the Primary Classroom

ERIC Educational Resources Information Center

Falloon, Garry

2017-01-01

Considerable work over many years has explored the contribution technology can make to science learning, at all levels of education. In the school sector, historically this has focused on the use of fixed, desktop-based or semi-mobile laptop systems for purposes such as experiment data collection or analysis, or as a means of engaging or…

STS-30 Atlantis, OV-104, at KSC LC Pad 39B atop mobile launcher platform

NASA Technical Reports Server (NTRS)

1989-01-01

STS-30 Atlantis, Orbiter Vehicle (OV) 104, arrives at Kennedy Space Center (KSC) Launch Complex (LC) Pad 39B atop mobile launcher platform. The fixed service structure (FSS) towers above OV-104, its external tank (ET), and its solid rocket boosters (SRBs). The rotating service structure (RSS) is retracted. The launch tower catwalks are also retracted.

76 FR 31252 - Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and 1626.5-1660...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-31

... also claims that MSS networks provide the only means to create a next generation air traffic management..., articulated their plans to offer high-speed data services, especially in connection with terrestrial networks... claimed that MSS networks provide the only means to create a next generation air traffic management (ATM...

Activation Mobilizes the Cholesterol in the Late Endosomes-Lysosomes of Niemann Pick Type C Cells

PubMed Central

Lange, Yvonne; Ye, Jin; Steck, Theodore L.

2012-01-01

A variety of intercalating amphipaths increase the chemical activity of plasma membrane cholesterol. To test whether intracellular cholesterol can be similarly activated, we examined NPC1 and NPC2 fibroblasts, since they accumulate large amounts of cholesterol in their late endosomes and lysosomes (LE/L). We gauged the mobility of intracellular sterol from its appearance at the surface of the intact cells, as determined by its susceptibility to cholesterol oxidase and its isotope exchange with extracellular 2-(hydroxypropyl)-β-cyclodextrin-cholesterol. The entire cytoplasmic cholesterol pool in these cells was mobile, exchanging with the plasma membrane with an apparent half-time of ∼3–4 hours, ∼4–5 times slower than that for wild type human fibroblasts (half-time ∼0.75 hours). The mobility of the intracellular cholesterol was increased by the membrane-intercalating amphipaths chlorpromazine and 1-octanol. Chlorpromazine also promoted the net transfer of LE/L cholesterol to serum and cyclodextrin. Surprisingly, the mobility of LE/L cholesterol was greatly stimulated by treating intact NPC cells with glutaraldehyde or formaldehyde. Similar effects were seen with wild type fibroblasts in which the LE/L cholesterol pool had been expanded using U18666A. We also showed that the cholesterol in the intracellular membranes of fixed wild-type fibroblasts was mobile; it was rapidly oxidized by cholesterol oxidase and was rapidly replenished by exogenous sterol. We conclude that a) the cholesterol in NPC cells can exit the LE/L (and the extensive membranous inclusions therein) over a few hours; b) this mobility is stimulated by the activation of the cholesterol with intercalating amphipaths; c) intracellular cholesterol is even more mobile in fixed cells; and d) amphipaths that activate cholesterol might be useful in treating NPC disease. PMID:22276143

Quantification of polyethylene degradation in mobile bearing knees: a retrieval analysis of the Anterior-Posterior-Glide (APG) and Rotating Platform (RP) Low Contact Stress (LCS) knee.

PubMed

Kop, Alan M; Swarts, Eric

2007-06-01

Routine qualitative observations of more than 850 polyethylene fixed and mobile bearings at our institution have noted minimal wear of mobile bearings. The APG mobile bearing is the most recent design variant of the LCS knee, allows multi-directional movement at the tibiofemoral articulation, and is posterior cruciate sparing. Even though it is difficult to perform, quantitative wear measurement is important in determining the likely longevity of new arthroplasty devices, and is especially relevant because of increasing numbers of new mobile bearing designs. We analyzed 10 retrieved APG and 7 retrieved RP tibial bearings (De Puy) with a mean implantation period of 33 (9-70) months. We used coordinate-measuring techniques to quantitatively determine linear penetration, and optical and scanning electron microscopy to assess wear mechanisms qualitatively. The mean total volume loss (superior and inferior articulations) of the APG and RP designs was 85 mm((3))/year and 77 mm((3))/year, respectively. Burnishing was the predominant wear mechanism, and to a lesser extent scratching, abrasion and pitting. Multidirectional scratching and abrasion were noted on the APG inserts inferiorly, whereas there was circumferential scratching on the RP inserts. Our short-term results for the APG and RP mobile bearing designs are similar and compare more than favorably with reported values for fixed-bearing designs. However, increased backside wear due to multidirectional movement may predispose the APG design to greater wear in the long term.

Variational algorithms for nonlinear smoothing applications

NASA Technical Reports Server (NTRS)

Bach, R. E., Jr.

1977-01-01

A variational approach is presented for solving a nonlinear, fixed-interval smoothing problem with application to offline processing of noisy data for trajectory reconstruction and parameter estimation. The nonlinear problem is solved as a sequence of linear two-point boundary value problems. Second-order convergence properties are demonstrated. Algorithms for both continuous and discrete versions of the problem are given, and example solutions are provided.

Computing eigenfunctions and eigenvalues of boundary-value problems with the orthogonal spectral renormalization method

NASA Astrophysics Data System (ADS)

Cartarius, Holger; Musslimani, Ziad H.; Schwarz, Lukas; Wunner, Günter

2018-03-01

The spectral renormalization method was introduced in 2005 as an effective way to compute ground states of nonlinear Schrödinger and Gross-Pitaevskii type equations. In this paper, we introduce an orthogonal spectral renormalization (OSR) method to compute ground and excited states (and their respective eigenvalues) of linear and nonlinear eigenvalue problems. The implementation of the algorithm follows four simple steps: (i) reformulate the underlying eigenvalue problem as a fixed-point equation, (ii) introduce a renormalization factor that controls the convergence properties of the iteration, (iii) perform a Gram-Schmidt orthogonalization process in order to prevent the iteration from converging to an unwanted mode, and (iv) compute the solution sought using a fixed-point iteration. The advantages of the OSR scheme over other known methods (such as Newton's and self-consistency) are (i) it allows the flexibility to choose large varieties of initial guesses without diverging, (ii) it is easy to implement especially at higher dimensions, and (iii) it can easily handle problems with complex and random potentials. The OSR method is implemented on benchmark Hermitian linear and nonlinear eigenvalue problems as well as linear and nonlinear non-Hermitian PT -symmetric models.

Short‐term time step convergence in a climate model

PubMed Central

Rasch, Philip J.; Taylor, Mark A.; Jablonowski, Christiane

2015-01-01

Abstract This paper evaluates the numerical convergence of very short (1 h) simulations carried out with a spectral‐element (SE) configuration of the Community Atmosphere Model version 5 (CAM5). While the horizontal grid spacing is fixed at approximately 110 km, the process‐coupling time step is varied between 1800 and 1 s to reveal the convergence rate with respect to the temporal resolution. Special attention is paid to the behavior of the parameterized subgrid‐scale physics. First, a dynamical core test with reduced dynamics time steps is presented. The results demonstrate that the experimental setup is able to correctly assess the convergence rate of the discrete solutions to the adiabatic equations of atmospheric motion. Second, results from full‐physics CAM5 simulations with reduced physics and dynamics time steps are discussed. It is shown that the convergence rate is 0.4—considerably slower than the expected rate of 1.0. Sensitivity experiments indicate that, among the various subgrid‐scale physical parameterizations, the stratiform cloud schemes are associated with the largest time‐stepping errors, and are the primary cause of slow time step convergence. While the details of our findings are model specific, the general test procedure is applicable to any atmospheric general circulation model. The need for more accurate numerical treatments of physical parameterizations, especially the representation of stratiform clouds, is likely common in many models. The suggested test technique can help quantify the time‐stepping errors and identify the related model sensitivities. PMID:27660669

Modeling the effects of pH and ionic strength on swelling of anionic polyelectrolyte gels

NASA Astrophysics Data System (ADS)

Drozdov, A. D.; deClaville Christiansen, J.

2015-07-01

A constitutive model is developed for the elastic response of an anionic polyelectrolyte gel under swelling in water with an arbitrary pH and an arbitrary molar fraction of dissolved monovalent salt. A gel is treated as a three-phase medium consisting of a solid phase (polymer network), solvent (water), and solute (mobile ions). Transport of solvent and solute is thought of as their diffusion through the polymer network accelerated by an electric field formed by mobile and fixed ions and accompanied by chemical reactions (dissociation of functional groups attached to polymer chains and formation of ion pairs between bound charges and mobile counter-ions). Constitutive equations are derived by means of the free energy imbalance inequality for an arbitrary three-dimensional deformation with finite strains. These relations are applied to analyze equilibrium swelling diagrams on poly(acrylic acid) gel, poly(methacrylic acid) gel, and three composite hydrogels under water uptake in a bath (i) with a fixed molar fraction of salt and varied pH, and (ii) with a fixed pH and varied molar fraction of salt. To validate the ability of the model to predict observations quantitatively, material constants are found by matching swelling curves under one type of experimental conditions and results of simulation are compared with experimental data in the other type of tests.

75 FR 80040 - Manufacturing Council

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-21

..., developing and marketing programs in support of manufacturing industries, job creation in the manufacturing... relevant contact information such as mailing address, fax, e-mail, fixed and mobile phone numbers and...

A new Concept for High Resolution Benthic Mapping and Data Aquisition: MANSIO-VIATOR

NASA Astrophysics Data System (ADS)

Flögel, S.

2015-12-01

Environmental conditions within sensitive seafloor ecosystems such as cold-seep provinces or cold-water coral reef communities vary temporally and spatially over a wide range of scales. Some of these are regularly monitored via short periods of intense shipborne activity or low resolution, fixed location studies by benthic lander systems. Long term measurements of larger areas and volumes are ususally coupled to costly infrastructure investments such as cabled observatories. In space exploration, a combination of fixed and mobile systems working together are commonly used, e.g. lander systems coupled to rovers, to tackle observational needs that are very similar to deep-sea data aquisition. The analogies between space and deep-sea research motivated the German Helmholtz Association to setup the joint research program ROBEX (Robotic Exploration under extreme conditions). The program objectives are to identify, develop and verify technological synergies between the robotic exploration of e.g. the moon and the deep-sea. Within ROBEX, the mobility of robots is a vital element for research missions due to valuable scientifice return potential from different sites as opposed to static landers. Within this context, we developed a new mobile crawler system (VIATOR, latin for traveller) and a fixed lander component for energy and data transfer (MANSIO, latin for housing/shelter). This innovative MANSIO-VIATOR system has been developed during the past 2.5 years. The caterpillar driven component is developed to conduct high resolution opitcal mapping and repeated monitoring of physical and biogeochemical parameters along transects. The system operates fully autonomously including navigational components such as camera and laser scanners, as well as marker based near-field navigation used in space technology. This new concept of data aquisition by a submarine crawler in combination with a fixed lander further opens up marine exploration possibilities.

Cost Evaluation of Reproductive and Primary Health Care Mobile Service Delivery for Women in Two Rural Districts in South Africa

PubMed Central

Schnippel, Kathryn; Lince-Deroche, Naomi; van den Handel, Theo; Molefi, Seithati; Bruce, Suann; Firnhaber, Cynthia

2015-01-01

Background Cervical cancer screening is a critical health service that is often unavailable to women in under-resourced settings. In order to expand access to this and other reproductive and primary health care services, a South African non-governmental organization established a van-based mobile clinic in two rural districts in South Africa. To inform policy and budgeting, we conducted a cost evaluation of this service delivery model. Methods The evaluation was retrospective (October 2012–September 2013 for one district and April–September 2013 for the second district) and conducted from a provider cost perspective. Services evaluated included cervical cancer screening, HIV counselling and testing, syndromic management of sexually transmitted infections (STIs), breast exams, provision of condoms, contraceptives, and general health education. Fixed costs, including vehicle purchase and conversion, equipment, operating costs and mobile clinic staffing, were collected from program records and public sector pricing information. The number of women accessing different services was multiplied by ingredients-based variable costs, reflecting the consumables required. All costs are reported in 2013 USD. Results Fixed costs accounted for most of the total annual costs of the mobile clinics (85% and 94% for the two districts); the largest contributor to annual fixed costs was staff salaries. Average costs per patient were driven by the total number of patients seen, at $46.09 and $76.03 for the two districts. Variable costs for Pap smears were higher than for other services provided, and some services, such as breast exams and STI and tuberculosis symptoms screening, had no marginal cost. Conclusions Staffing costs are the largest component of providing mobile health services to rural communities. Yet, in remote areas where patient volumes do not exceed nursing staff capacity, incorporating multiple services within a cervical cancer screening program is an approach to potentially expand access to health care without added costs. PMID:25751528

Cost evaluation of reproductive and primary health care mobile service delivery for women in two rural districts in South Africa.

PubMed

Schnippel, Kathryn; Lince-Deroche, Naomi; van den Handel, Theo; Molefi, Seithati; Bruce, Suann; Firnhaber, Cynthia

2015-01-01

Cervical cancer screening is a critical health service that is often unavailable to women in under-resourced settings. In order to expand access to this and other reproductive and primary health care services, a South African non-governmental organization established a van-based mobile clinic in two rural districts in South Africa. To inform policy and budgeting, we conducted a cost evaluation of this service delivery model. The evaluation was retrospective (October 2012-September 2013 for one district and April-September 2013 for the second district) and conducted from a provider cost perspective. Services evaluated included cervical cancer screening, HIV counselling and testing, syndromic management of sexually transmitted infections (STIs), breast exams, provision of condoms, contraceptives, and general health education. Fixed costs, including vehicle purchase and conversion, equipment, operating costs and mobile clinic staffing, were collected from program records and public sector pricing information. The number of women accessing different services was multiplied by ingredients-based variable costs, reflecting the consumables required. All costs are reported in 2013 USD. Fixed costs accounted for most of the total annual costs of the mobile clinics (85% and 94% for the two districts); the largest contributor to annual fixed costs was staff salaries. Average costs per patient were driven by the total number of patients seen, at $46.09 and $76.03 for the two districts. Variable costs for Pap smears were higher than for other services provided, and some services, such as breast exams and STI and tuberculosis symptoms screening, had no marginal cost. Staffing costs are the largest component of providing mobile health services to rural communities. Yet, in remote areas where patient volumes do not exceed nursing staff capacity, incorporating multiple services within a cervical cancer screening program is an approach to potentially expand access to health care without added costs.

Electron– and positron–molecule scattering: development of the molecular convergent close-coupling method

DOE PAGES

Zammit, Mark C.; Fursa, Dmitry V.; Savage, Jeremy S.; ...

2017-05-22

Starting from first principles, this tutorial describes the development of the adiabatic-nuclei convergent close-coupling (CCC) method and its application to electron and (single-centre) positron scattering from diatomic molecules. In this paper, we give full details of the single-centre expansion CCC method, namely the formulation of the molecular target structure; solving the momentum-space coupled-channel Lippmann-Schwinger equation; deriving adiabatic-nuclei cross sections and calculatingmore » $V$-matrix elements. Selected results are presented for electron and positron scattering from molecular hydrogen H$$_2$$ and electron scattering from the vibrationally excited molecular hydrogen ion H$$_2^+$$ and its isotopologues (D$$_2^+$$, T$$_2^+$$, HD$^+$, HT$^+$ and TD$^+$). Finally, convergence in both the close-coupling (target state) and projectile partial-wave expansions of fixed-nuclei electron- and positron-molecule scattering calculations is demonstrated over a broad energy-range and discussed in detail. In general the CCC results are in good agreement with experiments.« less

Adiabatic-nuclei calculations of positron scattering from molecular hydrogen

DOE PAGES

Zammit, Mark Christian; Fursa, Dmitry V.; Savage, Jeremy S.; ...

2017-02-06

The single-center adiabatic-nuclei convergent close-coupling method is used to investigate positron collisions with molecular hydrogen (H 2) in the ground and first vibrationally excited states. Cross sections are presented over the energy range from 1 to 1000 eV for elastic scattering, vibrational excitation, total ionization, and the grand total cross section. The present adiabatic-nuclei positron- H 2 scattering length is calculated as A = $-$ 2.70 a 0 for the ground state and A = $-$ 3.16 a 0 for the first vibrationally excited state. The present elastic differential cross sections are also used to “correct” the low-energy grand totalmore » cross-section measurements of the Trento group [A. Zecca et al., Phys. Rev. A 80, 032702 (2009)] for the forward-angle-scattering effect. In general, the comparison with experiment is good. In conclusion, by performing convergence studies, we estimate that our R m = 1.448 a 0 fixed-nuclei results are converged to within ± 5 % for the major scattering integrated cross sections.« less

Strategic Mobility and the Decline of the United States Merchant Marine

DTIC Science & Technology

1989-05-01

percent of the dry cargo and 99 percent. of the petroleum, ii oils , and lubricants (POL) used in the war. (5/8) Mobil ity planners expect this heavy...sh a prudertt, bla] fwr’t. be twcen DOD orgati,: sealift anid US merchant marine sealift. . b-o , Ilxi) organ i: :t1h i ., i t -- essentil 14 cc fix;d

Do mobile clinics provide high-quality antenatal care? A comparison of care delivery, knowledge outcomes and perception of quality of care between fixed and mobile clinics in central Haiti.

PubMed

Phillips, Erica; Stoltzfus, Rebecca J; Michaud, Lesly; Pierre, Gracia Lionel Fils; Vermeylen, Francoise; Pelletier, David

2017-10-16

Antenatal care (ANC) is an important health service for women in developing countries, with numerous proven benefits. Global coverage of ANC has steadily increased over the past 30 years, in part due to increased community-based outreach. However, commensurate improvements in health outcomes such as reductions in the prevalence of maternal anemia and infants born small-for-gestational age have not been achieved, even with increased coverage, indicating that quality of care may be inadequate. Mobile clinics are one community-based strategy used to further improve coverage of ANC, but their quality of care delivery has rarely been evaluated. To determine the quality of care of ANC in central Haiti, we compared adherence to national guidelines between fixed and mobile clinics by performing direct observations of antenatal care consultations and exit interviews with recipients of care using a multi-stage random sampling procedure. Outcome variables were eight components of care, and women's knowledge and perception of care quality. There were significant differences in the predicted proportion or probability of recommended services for four of eight care components, including intake, laboratory examinations, infection control, and supplies, iron folic acid supplements and Tetanus Toxoid vaccine provided to women. These care components were more likely performed in fixed clinics, except for distribution of supplies, iron-folic acid supplements, and Tetanus Toxoid vaccine, more likely provided in mobile clinics. There were no differences between clinic type for the proportion of total physical exam procedures performed, health and communication messages delivered, provider communication or documentation. Women's knowledge about educational topics was poor, but women perceived extremely high quality of care in both clinic models. Although adherence to guidelines differed by clinic type for half of the care components, both clinics had a low percentage of overall services delivered. Efforts to improve provider performance and quality are therefore needed in both models. Mobile clinics must deliver high-quality ANC to improve health and nutrition outcomes.

Message handling system concepts and services in a land mobile satellite system

NASA Technical Reports Server (NTRS)

Barberis, S.; Settimo, F.; Giralda, A.; Mistretta, I.; Loisy, C.; Parmentier, J. L.

1990-01-01

A network architecture containing the capabilities offered by the Message Handling System (MHS) to the PRODAT Land Mobile Satellite System (LMSS) is described taking into account the constraints of a preexisting satellite system which is going to become operational. The mapping between MHS services and PRODAT requirements is also reported and shows that the supplied performance can be significantly enhanced to both fixed and mobile users. The impact of the insertion of additional features on the system structure, especially on the centralized control unit, are also addressed.

75 FR 12507 - Manufacturing Council

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-16

... in the selection of Council members include candidates' proven experience in developing and marketing... contact information such as mailing address, fax, e-mail, fixed and mobile phone numbers and support staff...

Separability of electrostatic and hydrodynamic forces in particle electrophoresis

NASA Astrophysics Data System (ADS)

Todd, Brian A.; Cohen, Joel A.

2011-09-01

By use of optical tweezers we explicitly measure the electrostatic and hydrodynamic forces that determine the electrophoretic mobility of a charged colloidal particle. We test the ansatz of O'Brien and White [J. Chem. Soc. Faraday IIJCFTBS0300-923810.1039/f29787401607 74, 1607 (1978)] that the electrostatically and hydrodynamically coupled electrophoresis problem is separable into two simpler problems: (1) a particle held fixed in an applied electric field with no flow field and (2) a particle held fixed in a flow field with no applied electric field. For a system in the Helmholtz-Smoluchowski and Debye-Hückel regimes, we find that the electrostatic and hydrodynamic forces measured independently accurately predict the electrophoretic mobility within our measurement precision of 7%; the O'Brien and White ansatz holds under the conditions of our experiment.

Time-Frequency Analysis of Rocket Nozzle Wall Pressures During Start-up Transients

NASA Technical Reports Server (NTRS)

Baars, Woutijn J.; Tinney, Charles E.; Ruf, Joseph H.

2011-01-01

Surveys of the fluctuating wall pressure were conducted on a sub-scale, thrust- optimized parabolic nozzle in order to develop a physical intuition for its Fourier-azimuthal mode behavior during fixed and transient start-up conditions. These unsteady signatures are driven by shock wave turbulent boundary layer interactions which depend on the nozzle pressure ratio and nozzle geometry. The focus however, is on the degree of similarity between the spectral footprints of these modes obtained from transient start-ups as opposed to a sequence of fixed nozzle pressure ratio conditions. For the latter, statistically converged spectra are computed using conventional Fourier analyses techniques, whereas the former are investigated by way of time-frequency analysis. The findings suggest that at low nozzle pressure ratios -- where the flow resides in a Free Shock Separation state -- strong spectral similarities occur between fixed and transient conditions. Conversely, at higher nozzle pressure ratios -- where the flow resides in Restricted Shock Separation -- stark differences are observed between the fixed and transient conditions and depends greatly on the ramping rate of the transient period. And so, it appears that an understanding of the dynamics during transient start-up conditions cannot be furnished by a way of fixed flow analysis.

Network rewiring dynamics with convergence towards a star network

PubMed Central

Dick, G.; Parry, M.

2016-01-01

Network rewiring as a method for producing a range of structures was first introduced in 1998 by Watts & Strogatz (Nature 393, 440–442. (doi:10.1038/30918)). This approach allowed a transition from regular through small-world to a random network. The subsequent interest in scale-free networks motivated a number of methods for developing rewiring approaches that converged to scale-free networks. This paper presents a rewiring algorithm (RtoS) for undirected, non-degenerate, fixed size networks that transitions from regular, through small-world and scale-free to star-like networks. Applications of the approach to models for the spread of infectious disease and fixation time for a simple genetics model are used to demonstrate the efficacy and application of the approach. PMID:27843396

Network rewiring dynamics with convergence towards a star network.

PubMed

Whigham, P A; Dick, G; Parry, M

2016-10-01

Network rewiring as a method for producing a range of structures was first introduced in 1998 by Watts & Strogatz ( Nature 393 , 440-442. (doi:10.1038/30918)). This approach allowed a transition from regular through small-world to a random network. The subsequent interest in scale-free networks motivated a number of methods for developing rewiring approaches that converged to scale-free networks. This paper presents a rewiring algorithm (RtoS) for undirected, non-degenerate, fixed size networks that transitions from regular, through small-world and scale-free to star-like networks. Applications of the approach to models for the spread of infectious disease and fixation time for a simple genetics model are used to demonstrate the efficacy and application of the approach.

An updated Lagrangian particle hydrodynamics (ULPH) for Newtonian fluids

NASA Astrophysics Data System (ADS)

Tu, Qingsong; Li, Shaofan

2017-11-01

In this work, we have developed an updated Lagrangian particle hydrodynamics (ULPH) for Newtonian fluid. Unlike the smoothed particle hydrodynamics, the non-local particle hydrodynamics formulation proposed here is consistent and convergence. Unlike the state-based peridynamics, the discrete particle dynamics proposed here has no internal material bond between particles, and it is not formulated with respect to initial or a fixed referential configuration. In specific, we have shown that (1) the non-local update Lagrangian particle hydrodynamics formulation converges to the conventional local fluid mechanics formulation; (2) the non-local updated Lagrangian particle hydrodynamics can capture arbitrary flow discontinuities without any changes in the formulation, and (3) the proposed non-local particle hydrodynamics is computationally efficient and robust.

Severe fixed cervical kyphosis treated with circumferential osteotomy and pedicle screw fixation using an anterior-posterior-anterior surgical sequence.

PubMed

Yoshihara, Hiroyuki; Abumi, Kuniyoshi; Ito, Manabu; Kotani, Yoshihisa; Sudo, Hideki; Takahata, Masahiko

2013-11-01

Surgical treatment for severe circumferentially fixed cervical kyphosis has been challenging. Both anterior and posterior releases are necessary to provide the cervical mobility necessary for fusion in a corrected position. In two case reports, we describe the circumferential osteotomy of anterior-posterior-anterior surgical sequence, and the efficacy of this technique when cervical pedicle screw fixation for severe fixed cervical kyphosis is used. Etiology of fixed cervical kyphosis was unknown in one patient and neurofibromatosis in one patient. Both patients had severe fixed cervical kyphosis as determined by cervical radiographs and underwent circumferential osteotomy and fixation via an anterior-posterior-anterior surgical sequence and correction of kyphosis by pedicle screw fixation. Severe fixed cervical kyphosis was treated successfully by the use of circumferential osteotomy and pedicle screw fixation. The surgical sequence described in this report is a reasonable approach for severe circumferentially fixed cervical kyphosis and short segment fixation can be achieved using pedicle screws. Copyright © 2013 Elsevier Inc. All rights reserved.

Experimental considerations in metal mobilization from soil by chelating ligands: The influence of soil-solution ratio and pre-equilibration - A case study on Fe acquisition by phytosiderophores.

PubMed

Schenkeveld, W D C; Kimber, R L; Walter, M; Oburger, E; Puschenreiter, M; Kraemer, S M

2017-02-01

The efficiency of chelating ligands in mobilizing metals from soils and sediments is generally examined under conditions remote from those under which they are exuded or applied in the field. This may lead to incorrect estimations of the mobilizing efficiency. The aim of this study was to establish the influence of the soil solution ratio (SSR) and pre-equilibration with electrolyte solution on metal mobilization and metal displacement. For this purpose a series of interaction experiments with a calcareous clay soil and a biogenic chelating agent, the phytosiderophore 2'-deoxymugineic acid (DMA) were carried out. For a fixed ligand concentration, the SSR had a strong influence on metal mobilization and displacement. Metal complexation was faster at higher SSR. Reactive pools of metals that were predominantly mobilized at SSR 6 (in this case Cu), became depleted at SSR 0.1, whereas metals that were marginally mobilized at SSR 6, were dominantly mobilized at SSR 0.1 (in this case Fe), because of large soil reactive pools. For a fixed "amount of ligand"-to-"amount of soil"-ratio, metal complexation scaled linearly with the SSR. The efficiency of ligands in mobilizing metals under field conditions can be predicted with batch experiments, as long as the ligand-to-soil-ratio is matched. In most previously reported studies this criterion was not met. Equivalent metal-complex concentrations under field conditions can be back-calculated using adsorption isotherms for the respective metal-complexes. Drying and dry storage created labile pools of Fe, Cu and Zn, which were rapidly mobilized upon addition of DMA solution to dry soil. Pre-equilibration decreased these labile pools, leading to smaller concentrations of these metals during initial mobilization, but did not reduce the lag time between ligand addition and onset of microbial degradation of the metal-complexes. Hence SSR and pre-equilibration should be carefully considered when testing the metal mobilizing efficiency of chelating ligands. Copyright © 2016. Published by Elsevier B.V.

Mobile bearing vs fixed bearing prostheses for posterior cruciate retaining total knee arthroplasty for postoperative functional status in patients with osteoarthritis and rheumatoid arthritis.

PubMed

Hofstede, Stefanie N; Nouta, Klaas Auke; Jacobs, Wilco; van Hooff, Miranda L; Wymenga, Ate B; Pijls, Bart G; Nelissen, Rob G H H; Marang-van de Mheen, Perla J

2015-02-04

It is unclear whether there are differences in benefits and harms between mobile and fixed prostheses for total knee arthroplasty (TKA). The previous Cochrane review published in 2004 included two articles. Many more trials have been performed since then; therefore an update is needed. To assess the benefits and harms of mobile bearing compared with fixed bearing cruciate retaining total knee arthroplasty for functional and clinical outcomes in patients with osteoarthritis (OA) or rheumatoid arthritis (RA). We searched The Cochrane Library, PubMed, EMBASE, CINAHL and Web of Science up to 27 February 2014, and the trial registers ClinicalTrials.gov, Multiregister, Current Controlled Trials and the World Health Organization (WHO) International Clinical Trials Registry Platform for data from unpublished trials, up to 11 February 2014. We also screened the reference lists of selected articles. We selected randomised controlled trials comparing mobile bearing with fixed bearing prostheses in cruciate retaining TKA among patients with osteoarthritis or rheumatoid arthritis, using functional or clinical outcome measures and follow-up of at least six months. We used standard methodological procedures as expected by The Cochrane Collaboration. We found 19 studies with 1641 participants (1616 with OA (98.5%) and 25 with RA (1.5%)) and 2247 knees. Seventeen new studies were included in this update.Quality of the evidence ranged from moderate (knee pain) to low (other outcomes). Most studies had unclear risk of bias for allocation concealment, blinding of participants and personnel, blinding of outcome assessment and selective reporting, and high risk of bias for incomplete outcome data and other bias. Knee painWe calculated the standardised mean difference (SMD) for pain, using the Knee Society Score (KSS) and visual analogue scale (VAS) in 11 studies (58%) and 1531 knees (68%). No statistically significant differences between groups were reported (SMD 0.09, 95% confidence interval (CI) -0.03 to 0.22, P value 0.15). This represents an absolute risk difference of 2.4% points higher (95% CI 0.8% lower to 5.9% higher) on the KSS pain scale and a relative percent change of 0.22% (95% CI 0.07% lower to 0.53% higher). The results were homogeneous. Clinical and functional scores The KSS clinical score did not differ statistically significantly between groups (14 studies (74%) and 1845 knees (82%)) with a mean difference (MD) of -1.06 points (95% CI -2.87 to 0.74, P value 0.25) and heterogeneous results. KSS function was reported in 14 studies (74%) with 1845 knees (82%) as an MD of -0.10 point (95% CI -1.93 to 1.73, P value 0.91) and homogeneous results. In two studies (11%), the KSS total score was favourable for mobile bearing (159 vs 132 for fixed bearing), with MD of -26.52 points (95% CI -45.03 to -8.01, P value 0.005), but with a wide 95% confidence interval indicating uncertainty about the estimate.Other reported scoring systems did not show statistically significant differences: Hospital for Special Surgery (HSS) score (seven studies (37%) in 1021 knees (45%)) with an MD of -1.36 (95% CI -4.18 to 1.46, P value 0.35); Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (two studies (11%), 167 knees (7%)) with an MD of -4.46 (95% CI -16.26 to 7.34, P value 0.46); and Oxford total (five studies (26%), 647 knees (29%) with an MD of -0.25 (95% CI -1.41 to 0.91, P value 0.67). Health-related quality of lifeThree studies (16%) with 498 knees (22%) reported on health-related quality of life, and no statistically significant differences were noted between the mobile bearing and fixed bearing groups. The Short Form (SF)-12 Physical Component Summary had an MD of -1.96 (95% CI -4.55 to 0.63, P value 0.14) and heterogeneous results. Revision surgeryTwenty seven revisions (1.3%) were performed in 17 studies (89%) with 2065 knees (92%). In all, 13 knees were revised in the fixed bearing group and 14 knees in the mobile bearing group. No statistically significant differences were found (risk difference 0.00, 95% CI -0.01 to 0.01, P value 0.58), and homogeneous results were reported. MortalityIn seven out of 19 studies, 13 participants (37%) died. Two of these participants had undergone bilateral surgery, and for seven participants, it was unclear which prosthesis they had received; therefore they were excluded from the analyses. Thus our analysis included four out of 191 participants (2.1%) who had died: one in the fixed bearing group and three in the mobile bearing group. No statistically significant differences were found. The risk difference was -0.02 (95% CI -0.06 to 0.03, P value 0.49) and results were homogeneous. Reoperation ratesThirty reoperations were performed in 17 studies (89%) with 2065 knees (92%): 18 knees in the fixed bearing group (of the 1031 knees) and 12 knees in the mobile group (of the 1034 knees). No statistically significant differences were found. The risk difference was -0.01 (95% CI -0.01 to 0.01, P value 0.99) with homogeneous results. Other serious adverse eventsSixteen studies (84%) reported nine other serious adverse events in 1735 knees (77%): four in the fixed bearing group (of the 862 knees) and five in the mobile bearing group (of the 873 knees). No statistically significant differences were found (risk difference 0.00, 95% CI -0.01 to 0.01, P value 0.88), and results were homogeneous. Moderate- to low-quality evidence suggests that mobile bearing prostheses may have similar effects on knee pain, clinical and functional scores, health-related quality of life, revision surgery, mortality, reoperation rate and other serious adverse events compared with fixed bearing prostheses in posterior cruciate retaining TKA. Therefore we cannot draw firm conclusions. Most (98.5%) participants had OA, so the findings primarily reflect results reported in participants with OA. Future studies should report in greater detail outcomes such as those presented in this systematic review, with sufficient follow-up time to allow gathering of high-quality evidence and to inform clinical practice. Large registry-based studies may have added value, but they are subject to treatment-by-indication bias. Therefore, this systematic review of RCTs can be viewed as the best available evidence.

Local Improvement Results for Anderson Acceleration with Inaccurate Function Evaluations

DOE PAGES

Toth, Alex; Ellis, J. Austin; Evans, Tom; ...

2017-10-26

Here, we analyze the convergence of Anderson acceleration when the fixed point map is corrupted with errors. We also consider uniformly bounded errors and stochastic errors with infinite tails. We prove local improvement results which describe the performance of the iteration up to the point where the accuracy of the function evaluation causes the iteration to stagnate. We illustrate the results with examples from neutronics.

Local Improvement Results for Anderson Acceleration with Inaccurate Function Evaluations

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

Toth, Alex; Ellis, J. Austin; Evans, Tom

Here, we analyze the convergence of Anderson acceleration when the fixed point map is corrupted with errors. We also consider uniformly bounded errors and stochastic errors with infinite tails. We prove local improvement results which describe the performance of the iteration up to the point where the accuracy of the function evaluation causes the iteration to stagnate. We illustrate the results with examples from neutronics.

Correlates of mobile screen media use among children aged 0-8: protocol for a systematic review.

PubMed

Paudel, Susan; Leavy, Justine; Jancey, Jonine

2016-06-03

Childhood is a crucial period for shaping healthy behaviours; however, it currently appears to be dominated by screen time. A large proportion of young children do not adhere to the screen time recommendations, with the use of mobile screen devices becoming more common than fixed screens. Existing systematic reviews on correlates of screen time have focused largely on the traditional fixed screen devices such as television. Reviews specially focused on mobile screen media are almost non-existent. This paper describes the protocol for conducting a systematic review of papers published between 2009 and 2015 to identify the correlates of mobile screen media use among children aged 0-8 years. A systematic literature search of electronic databases will be carried out using different combinations of keywords for papers published in English between January 2009 and December 2015. Additionally, a manual search of reference lists and citations will also be conducted. Papers that have examined correlates of screen time among children aged 0-8 will be included in the review. Studies must include at least one type of mobile screen media (mobile phones, electronic tablets or handheld computers) to be eligible for inclusion. This study will identify correlates of mobile screen-viewing among children in five categories: (i) child biological and demographic correlates, (ii) behavioural correlates, (iii) family biological and demographic correlates, (iv) family structure-related correlates and (v) socio-cultural and environmental correlates. PRISMA statement will be used for ensuring transparency and scientific reporting of the results. This study will identify the correlates associated with increased mobile screen media use among young children through the systematic review of published peer-reviewed papers. This will contribute to addressing the knowledge gap in this area. The results will provide an evidence base to better understand correlates of mobile screen media use and potentially inform the development of recommendations to reduce screen time among those aged 0-8 years. PROSPERO CRD42015028028 .

47 CFR 22.1007 - Channels for offshore radiotelephone systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... emergency auto alarm and voice transmission pertaining to emergency conditions only. Central Subscriber 488... fixed, surface and/or airborne mobile) as indicated, for emergency auto alarm and voice transmission...

47 CFR 22.1007 - Channels for offshore radiotelephone systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... emergency auto alarm and voice transmission pertaining to emergency conditions only. Central Subscriber 488... fixed, surface and/or airborne mobile) as indicated, for emergency auto alarm and voice transmission...

47 CFR 22.1007 - Channels for offshore radiotelephone systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... emergency auto alarm and voice transmission pertaining to emergency conditions only. Central Subscriber 488... fixed, surface and/or airborne mobile) as indicated, for emergency auto alarm and voice transmission...

7 CFR 1735.10 - General.

Code of Federal Regulations, 2011 CFR

2011-01-01

... cost-of-money loans, or RTB loans for any wireline local exchange service or similar fixed-station... plan is not technically or economically feasible. (c) A borrower receiving a loan to provide mobile...

7 CFR 1735.10 - General.

Code of Federal Regulations, 2010 CFR

2010-01-01

... cost-of-money loans, or RTB loans for any wireline local exchange service or similar fixed-station... plan is not technically or economically feasible. (c) A borrower receiving a loan to provide mobile...

The mobile hospital technology industry: focus on the computerized tomography scanner.

PubMed

Hartley, D; Moscovice, I

1996-01-01

This study of firms offering mobile hospital technology to rural hospitals in eight northwestern states found that several permanently parked computerized tomography (CT) units were found where mobile routes had atrophied due to the purchase of fixed units by former mobile CT hospital clients. Based on a criterion of 140 scans per month per unit as a threshold of profitable production, units owned by larger firms (those that operate five or more units) were more likely to be profitable than units owned by smaller firms (71% versus 20%, P = 0.03). A substantial number of rural hospitals lose money on mobile CT due to low Medicare reimbursement. In some areas, mobile hospital technology is a highly competitive industry. Evidence was found that several firms compete in some geographic areas and that some firms have lost hospital clients to competing vendors.

Mobile data buoy system. [water quality measurements in watersheds and Mobile Bay, Alabama

NASA Technical Reports Server (NTRS)

Morton, R. A.

1975-01-01

The Mobile Data Buoy System was conceived to serve the users requirement for obtaining water quality parameters from two separate watershed systems. In view of the cost constraints of the ERTS program it was obvious that the network of 10 sampling stations required could not be of the fixed installation type; therefore, it was decided to go to a system of battery powered buoys of a size that could be used in one watershed system for a period of time and then moved to another by use of a relatively small 6.7 m (22 foot) boat. The basic idea of the water quality measurement program was to establish the water quality pattern of change from the headwaters of the watersheds to and through the Mobile Bay. This would allow the investigator to develop a good picture of the state's major water resources and the pressures from pollution that are being imposed. At this point in deployment of this mobile system of buoys, it is too early to put a quantitative value on the system, however it appears less expensive than known fixed installations as to first cost. It has a basic advantage in that it can be moved, at very little expense, to alternate sites where it is desired to obtain water quality data. It is to be noted this buoy system which covers a 80 Km (50 mile) stretch of the Black Warrior River and then skips down 483 Km (300 miles) to Mobile Bay for the next measurements would not be feasible unless there is a satellite to collect and relay the data.

Adaptive Control Parameters for Dispersal of Multi-Agent Mobile Ad Hoc Network (MANET) Swarms

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

Kurt Derr; Milos Manic

A mobile ad hoc network is a collection of independent nodes that communicate wirelessly with one another. This paper investigates nodes that are swarm robots with communications and sensing capabilities. Each robot in the swarm may operate in a distributed and decentralized manner to achieve some goal. This paper presents a novel approach to dynamically adapting control parameters to achieve mesh configuration stability. The presented approach to robot interaction is based on spring force laws (attraction and repulsion laws) to create near-optimal mesh like configurations. In prior work, we presented the extended virtual spring mesh (EVSM) algorithm for the dispersionmore » of robot swarms. This paper extends the EVSM framework by providing the first known study on the effects of adaptive versus static control parameters on robot swarm stability. The EVSM algorithm provides the following novelties: 1) improved performance with adaptive control parameters and 2) accelerated convergence with high formation effectiveness. Simulation results show that 120 robots reach convergence using adaptive control parameters more than twice as fast as with static control parameters in a multiple obstacle environment.« less

Asymptotic safety of quantum gravity beyond Ricci scalars

NASA Astrophysics Data System (ADS)

Falls, Kevin; King, Callum R.; Litim, Daniel F.; Nikolakopoulos, Kostas; Rahmede, Christoph

2018-04-01

We investigate the asymptotic safety conjecture for quantum gravity including curvature invariants beyond Ricci scalars. Our strategy is put to work for families of gravitational actions which depend on functions of the Ricci scalar, the Ricci tensor, and products thereof. Combining functional renormalization with high order polynomial approximations and full numerical integration we derive the renormalization group flow for all couplings and analyse their fixed points, scaling exponents, and the fixed point effective action as a function of the background Ricci curvature. The theory is characterized by three relevant couplings. Higher-dimensional couplings show near-Gaussian scaling with increasing canonical mass dimension. We find that Ricci tensor invariants stabilize the UV fixed point and lead to a rapid convergence of polynomial approximations. We apply our results to models for cosmology and establish that the gravitational fixed point admits inflationary solutions. We also compare findings with those from f (R ) -type theories in the same approximation and pin-point the key new effects due to Ricci tensor interactions. Implications for the asymptotic safety conjecture of gravity are indicated.

Measuring the global information society - explaining digital inequality by economic level and education standard

NASA Astrophysics Data System (ADS)

Ünver, H.

2017-02-01

A main focus of this research paper is to investigate on the explanation of the ‘digital inequality’ or ‘digital divide’ by economic level and education standard of about 150 countries worldwide. Inequality regarding GDP per capita, literacy and the so-called UN Education Index seem to be important factors affecting ICT usage, in particular Internet penetration, mobile phone usage and also mobile Internet services. Empirical methods and (multivariate) regression analysis with linear and non-linear functions are useful methods to measure some crucial factors of a country or culture towards becoming information and knowledge based society. Overall, the study concludes that the convergence regarding ICT usage proceeds worldwide faster than the convergence in terms of economic wealth and education in general. The results based on a large data analysis show that the digital divide is declining over more than a decade between 2000 and 2013, since more people worldwide use mobile phones and the Internet. But a high digital inequality explained to a significant extent by the functional relation between technology penetration rates, education level and average income still exists. Furthermore it supports the actions of countries at UN/G20/OECD level for providing ICT access to all people for a more balanced world in context of sustainable development by postulating that policymakers need to promote comprehensive education worldwide by means of using ICT.

Performance evaluation of power control algorithms in wireless cellular networks

NASA Astrophysics Data System (ADS)

Temaneh-Nyah, C.; Iita, V.

2014-10-01

Power control in a mobile communication network intents to control the transmission power levels in such a way that the required quality of service (QoS) for the users is guaranteed with lowest possible transmission powers. Most of the studies of power control algorithms in the literature are based on some kind of simplified assumptions which leads to compromise in the validity of the results when applied in a real environment. In this paper, a CDMA network was simulated. The real environment was accounted for by defining the analysis area and the network base stations and mobile stations are defined by their geographical coordinates, the mobility of the mobile stations is accounted for. The simulation also allowed for a number of network parameters including the network traffic, and the wireless channel models to be modified. Finally, we present the simulation results of a convergence speed based comparative analysis of three uplink power control algorithms.

Compendium of Applications Technology Satellite user experiments

NASA Technical Reports Server (NTRS)

Engler, N. A.; Strange, J. D.; Hein, G. F.

1976-01-01

The achievements of the user experiments performed with ATS satellites from 1967 to 1973 are summarized. Included are fixed and mobile point to point communications experiments involving voice, teletype and facsimile transmissions. Particular emphasis is given to the Alaska and Hawaii satellite communications experiments. The use of the ATS satellites for ranging and position fixing of ships and aircraft is also covered. The structure and operating characteristics of the various ATS satellite are briefly described.

Helicopters: The Platform of Choice for Defense and Development

DTIC Science & Technology

2013-04-25

FID effort by facilitating the IDAD tasks of balanced development, security, neutralization, and mobilization. In order to prevent instability...security, neutralization, and mobilization. In order to prevent instability inside a Host Nation (HN), it is important to build cohesive IDAD and...derived from the H -53 (arguably the oldest, biggest, and most cost-prohibitive platform of this type) compared to STOL-capable 4-9 passenger fixed wing

76 FR 49364 - Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and 1626.5-1660...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-10

... published pursuant to 47 CFR 1.429(e). See 1.4(b)(1) of the Commission's rules, 47 CFR 1.4(b)(1). DATES... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 1, 2, and 25 [ET Docket No. 10-142; Report 2932..., DC or may be purchased from the Commission's copy contractor, Best Copy and Printing, Inc. (BCPI) (1...

Director, Operational Test and Evaluation FY 2004 Annual Report

DTIC Science & Technology

2004-01-01

HIGH) Space Based Radar (SBR) Sensor Fuzed Weapon (SFW) P3I (CBU-97/B) Small Diameter Bomb (SDB) Secure Mobile Anti-Jam Reliable Tactical Terminal...detection, identification, and sampling capability for both fixed-site and mobile operations. The system must automatically detect and identify up to ten...staffing within the Services. SYSTEM DESCRIPTION AND MISSION The Services envision JCAD as a hand-held device that automatically detects, identifies, and

Review and Recommendations for the Interagency Ship Structure Committee’s Fiscal 1984 Research Program,

DTIC Science & Technology

1983-01-01

Daily. Proposal Evaluation Procedure Organizations interested in doing the work adverstised submit proposals and cost estimates. The USCG contracting...types of offshore structures. These structures have largely been fixed platforms for petroleum drilling and production, and mobile offshore drilling...structures and of those mobile drilling units that are bottom supported, such as jack-ups and submersibles. Structures which are held in place by anchors

Cyber threat model for tactical radio networks

NASA Astrophysics Data System (ADS)

Kurdziel, Michael T.

2014-05-01

The shift to a full information-centric paradigm in the battlefield has allowed ConOps to be developed that are only possible using modern network communications systems. Securing these Tactical Networks without impacting their capabilities has been a challenge. Tactical networks with fixed infrastructure have similar vulnerabilities to their commercial counterparts (although they need to be secure against adversaries with greater capabilities, resources and motivation). However, networks with mobile infrastructure components and Mobile Ad hoc Networks (MANets) have additional unique vulnerabilities that must be considered. It is useful to examine Tactical Network based ConOps and use them to construct a threat model and baseline cyber security requirements for Tactical Networks with fixed infrastructure, mobile infrastructure and/or ad hoc modes of operation. This paper will present an introduction to threat model assessment. A definition and detailed discussion of a Tactical Network threat model is also presented. Finally, the model is used to derive baseline requirements that can be used to design or evaluate a cyber security solution that can be scaled and adapted to the needs of specific deployments.

A brain-machine interface to navigate a mobile robot in a planar workspace: enabling humans to fly simulated aircraft with EEG.

PubMed

Akce, Abdullah; Johnson, Miles; Dantsker, Or; Bretl, Timothy

2013-03-01

This paper presents an interface for navigating a mobile robot that moves at a fixed speed in a planar workspace, with noisy binary inputs that are obtained asynchronously at low bit-rates from a human user through an electroencephalograph (EEG). The approach is to construct an ordered symbolic language for smooth planar curves and to use these curves as desired paths for a mobile robot. The underlying problem is then to design a communication protocol by which the user can, with vanishing error probability, specify a string in this language using a sequence of inputs. Such a protocol, provided by tools from information theory, relies on a human user's ability to compare smooth curves, just like they can compare strings of text. We demonstrate our interface by performing experiments in which twenty subjects fly a simulated aircraft at a fixed speed and altitude with input only from EEG. Experimental results show that the majority of subjects are able to specify desired paths despite a wide range of errors made in decoding EEG signals.

Interference Analysis for an Aeronautical Mobile Airport Communications System

NASA Technical Reports Server (NTRS)

Wilson, Jeffrey D.; Kercewski, Robert J.

2010-01-01

The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091- 5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this paper.12

Interference Analysis for an Aeronautical Mobile Airport Communications System

NASA Technical Reports Server (NTRS)

Wilson, Jeffrey D.; Kerczewski, Robert J.

2011-01-01

The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091-5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this presentation.

Health status convergence at the local level: empirical evidence from Austria

PubMed Central

2011-01-01

Introduction Health is an important dimension of welfare comparisons across individuals, regions and states. Particularly from a long-term perspective, within-country convergence of the health status has rarely been investigated by applying methods well established in other scientific fields. In the following paper we study the relation between initial levels of the health status and its improvement at the local community level in Austria in the time period 1969-2004. Methods We use age standardized mortality rates from 2381 Austrian communities as an indicator for the health status and analyze the convergence/divergence of overall mortality for (i) the whole population, (ii) females, (iii) males and (iv) the gender mortality gap. Convergence/Divergence is studied by applying different concepts of cross-regional inequality (weighted standard deviation, coefficient of variation, Theil-Coefficient of inequality). Various econometric techniques (weighted OLS, Quantile Regression, Kendall's Rank Concordance) are used to test for absolute and conditional beta-convergence in mortality. Results Regarding sigma-convergence, we find rather mixed results. While the weighted standard deviation indicates an increase in equality for all four variables, the picture appears less clear when correcting for the decreasing mean in the distribution. However, we find highly significant coefficients for absolute and conditional beta-convergence between the periods. While these results are confirmed by several robustness tests, we also find evidence for the existence of convergence clubs. Conclusions The highly significant beta-convergence across communities might be caused by (i) the efforts to harmonize and centralize the health policy at the federal level in Austria since the 1970s, (ii) the diminishing returns of the input factors in the health production function, which might lead to convergence, as the general conditions (e.g. income, education etc.) improve over time, and (iii) the mobility of people across regions, as people tend to move to regions/communities which exhibit more favorable living conditions. JEL classification: I10, I12, I18 PMID:21864364

Exponential parameter and tracking error convergence guarantees for adaptive controllers without persistency of excitation

NASA Astrophysics Data System (ADS)

Chowdhary, Girish; Mühlegg, Maximilian; Johnson, Eric

2014-08-01

In model reference adaptive control (MRAC) the modelling uncertainty is often assumed to be parameterised with time-invariant unknown ideal parameters. The convergence of parameters of the adaptive element to these ideal parameters is beneficial, as it guarantees exponential stability, and makes an online learned model of the system available. Most MRAC methods, however, require persistent excitation of the states to guarantee that the adaptive parameters converge to the ideal values. Enforcing PE may be resource intensive and often infeasible in practice. This paper presents theoretical analysis and illustrative examples of an adaptive control method that leverages the increasing ability to record and process data online by using specifically selected and online recorded data concurrently with instantaneous data for adaptation. It is shown that when the system uncertainty can be modelled as a combination of known nonlinear bases, simultaneous exponential tracking and parameter error convergence can be guaranteed if the system states are exciting over finite intervals such that rich data can be recorded online; PE is not required. Furthermore, the rate of convergence is directly proportional to the minimum singular value of the matrix containing online recorded data. Consequently, an online algorithm to record and forget data is presented and its effects on the resulting switched closed-loop dynamics are analysed. It is also shown that when radial basis function neural networks (NNs) are used as adaptive elements, the method guarantees exponential convergence of the NN parameters to a compact neighbourhood of their ideal values without requiring PE. Flight test results on a fixed-wing unmanned aerial vehicle demonstrate the effectiveness of the method.

[Validation of two brief scales for Internet addiction and mobile phone problem use].

PubMed

Beranuy Fargues, Marta; Chamarro Lusar, Andrés; Graner Jordania, Carla; Carbonell Sánchez, Xavier

2009-08-01

This study describes the construction and validation process of two questionnaires designed to assess the addictive use of Internet and mobile phones. The scales were applied to a sample of 1,879 students. Results support a two-factor model, presenting an acceptable internal consistency and indices of convergent and discriminant validity. The Questionnaire of Experiences Related to Internet was found to assess intra- and interpersonal conflicts related to Internet use. The Questionnaire of Experiences Related to the Mobile Phone was found to assess conflicts related to mobile phone abuse and to maladaptive emotional and communicational patterns. Our results indicate that the mobile phone does not produce the same degree of addictive behavior as Internet; it could rather be interpreted as problematic use. Men displayed more addictive use of Internet, whilst women seemed to use the mobile phone as a means for emotional communication. It seems that the use of both technologies is more problematic during adolescence and normalizes with age toward a more professional and less playful use, and with fewer negative consequences.

Emerging interdisciplinary fields in the coming intelligence/convergence era

NASA Astrophysics Data System (ADS)

Noor, Ahmed K.

2012-09-01

Dramatic advances are in the horizon resulting from rapid pace of development of several technologies, including, computing, communication, mobile, robotic, and interactive technologies. These advances, along with the trend towards convergence of traditional engineering disciplines with physical, life and other science disciplines will result in the development of new interdisciplinary fields, as well as in new paradigms for engineering practice in the coming intelligence/convergence era (post-information age). The interdisciplinary fields include Cyber Engineering, Living Systems Engineering, Biomechatronics/Robotics Engineering, Knowledge Engineering, Emergent/Complexity Engineering, and Multiscale Systems engineering. The paper identifies some of the characteristics of the intelligence/convergence era, gives broad definition of convergence, describes some of the emerging interdisciplinary fields, and lists some of the academic and other organizations working in these disciplines. The need is described for establishing a Hierarchical Cyber-Physical Ecosystem for facilitating interdisciplinary collaborations, and accelerating development of skilled workforce in the new fields. The major components of the ecosystem are listed. The new interdisciplinary fields will yield critical advances in engineering practice, and help in addressing future challenges in broad array of sectors, from manufacturing to energy, transportation, climate, and healthcare. They will also enable building large future complex adaptive systems-of-systems, such as intelligent multimodal transportation systems, optimized multi-energy systems, intelligent disaster prevention systems, and smart cities.

Mobile phones in Africa: how much do we really know?

PubMed

James, Jeffrey; Versteeg, Mila

2007-10-01

Mobile phones are a crucial mode of communication and welfare enhancement in poor countries, especially those lacking an infrastructure of fixed lines. In recent years much has been written about how mobile telephony in Africa is rapidly reducing the digital divide with developed countries. Yet, when one examines the evidence it is not at all clear what is really happening. In one country, Tanzania, for example, some observers point to the fact that 97% of the population lives under the mobile footprint, while others show that ownership is very limited. These extreme values prompted us to review the situation in Africa as a whole, in an effort to discover what is really going on.

Development of the network architecture of the Canadian MSAT system

NASA Technical Reports Server (NTRS)

Davies, N. George; Shoamanesh, Alireza; Leung, Victor C. M.

1988-01-01

A description is given of the present concept for the Canadian Mobile Satellite (MSAT) System and the development of the network architecture which will accommodate the planned family of three categories of service: a mobile radio service (MRS), a mobile telephone service (MTS), and a mobile data service (MDS). The MSAT satellite will have cross-strapped L-band and Ku-band transponders to provide communications services between L-band mobile terminals and fixed base stations supporting dispatcher-type MRS, gateway stations supporting MTS interconnections to the public telephone network, data hub stations supporting the MDS, and the network control center. The currently perceived centralized architecture with demand assignment multiple access for the circuit switched MRS, MTS and permanently assigned channels for the packet switched MDS is discussed.

Information Sharing Modalities for Mobile Ad-Hoc Networks

NASA Astrophysics Data System (ADS)

de Spindler, Alexandre; Grossniklaus, Michael; Lins, Christoph; Norrie, Moira C.

Current mobile phone technologies have fostered the emergence of a new generation of mobile applications. Such applications allow users to interact and share information opportunistically when their mobile devices are in physical proximity or close to fixed installations. It has been shown how mobile applications such as collaborative filtering and location-based services can take advantage of ad-hoc connectivity to use physical proximity as a filter mechanism inherent to the application logic. We discuss the different modes of information sharing that arise in such settings based on the models of persistence and synchronisation. We present a platform that supports the development of applications that can exploit these modes of ad-hoc information sharing and, by means of an example, show how such an application can be realised based on the supported event model.

Development of the network architecture of the Canadian MSAT system

NASA Astrophysics Data System (ADS)

Davies, N. George; Shoamanesh, Alireza; Leung, Victor C. M.

1988-05-01

A description is given of the present concept for the Canadian Mobile Satellite (MSAT) System and the development of the network architecture which will accommodate the planned family of three categories of service: a mobile radio service (MRS), a mobile telephone service (MTS), and a mobile data service (MDS). The MSAT satellite will have cross-strapped L-band and Ku-band transponders to provide communications services between L-band mobile terminals and fixed base stations supporting dispatcher-type MRS, gateway stations supporting MTS interconnections to the public telephone network, data hub stations supporting the MDS, and the network control center. The currently perceived centralized architecture with demand assignment multiple access for the circuit switched MRS, MTS and permanently assigned channels for the packet switched MDS is discussed.

Mobile-bearing knee systems: ultra-high molecular weight polyethylene wear and design issues.

PubMed

Greenwald, A Seth; Heim, Christine S

2005-01-01

In June 2004, the U.S. Food and Drug Administration Orthopaedic Advisory Panel recommended the reclassification of mobile-bearing knee systems for general use. This reflects the increasing use of mobile-bearing knee systems internationally, which is currently limited in the United States by regulatory requirement. Mobile-bearing knee systems are distinguished from conventional, fixed-plateau systems in that they allow dual-surface articulation between an ultra-high molecular weight polyethylene insert and metallic femoral and tibial tray components. Their in vivo success is dependent on patient selection, design, and material choice, as well as surgical precision during implantation. Laboratory and clinical experience extending over 25 years with individual systems suggests that mobile-bearing knee systems represent a viable treatment option for patients with knee arthrosis.

Global Interconnectivity Between Mobile Satellite and Terrestrial Users: Call Signalling Issues and Challenges

NASA Technical Reports Server (NTRS)

Estabrook, Polly; Moon, Todd; Spade, Rob

1996-01-01

This paper will discuss some of the challenges in connecting mobile satellite users and mobile terrestrial users in a cost efficient manner and with a grade of service comparable to that of satellite to fixed user calls. Issues arising from the translation between the mobility management protocols resident at the satellite Earth station and those resident at cellular switches - either GSM (Group Special Mobile) or IS-41 (used by U.S. digital cellular systems) type - will be discussed. The impact of GSM call routing procedures on the call setup of a satellite to roaming GSM user will be described. Challenges facing provision of seamless call handoff between satellite and cellular systems will be given. A summary of the issues explored in the paper are listed and future work outlined.

Meta-analysis and systematic review of clinical outcomes comparing mobile bearing and fixed bearing total knee arthroplasty.

PubMed

Smith, Holly; Jan, Meryam; Mahomed, Nizar N; Davey, J Rod; Gandhi, Rajiv

2011-12-01

Mobile bearing (MB) knee replacements were designed with the goal of increased conformity and decreased bearing wear. We conducted a meta-analysis and systematic review of randomized controlled trials comparing outcomes of MB and fixed bearing (FB) total knee arthroplasty (TKA). We identified 14 studies reporting our primary outcome of Knee Society Scores (KSS). We also pooled data for post-operative range of motion (ROM) and Hospital for Special Surgery scores (HSS). The standard difference in mean outcome scores for KSS and HSS demonstrated no difference between groups (P = .902, and P = .426 respectively). Similarly, the pooled data for ROM showed no difference between groups (P = .265). The results of this study found no significant differences between clinical outcomes of MB and FB TKA. Copyright © 2011 Elsevier Inc. All rights reserved.

No difference in joint awareness after mobile- and fixed-bearing total knee arthroplasty: 3-year follow-up of a randomized controlled trial.

PubMed

Schotanus, M G M; Pilot, P; Vos, R; Kort, N P

2017-12-01

To compare the patients ability to forget the artificial knee joint in everyday life who were randomized to be operated for mobile- or fixed-bearing total knee arthroplasty (TKA). This single-center randomized controlled trial evaluated the 3-year follow-up of the cemented mobile- and fixed-bearing TKA from the same brand in a series of 41 patients. Clinical examination was during the pre-, 6-week, 6-month, 1-, 2- and 3-year follow-up containing multiple patient-reported outcome measures (PROMs) including the 12-item Forgotten Joint Score (FJS-12) at 3 years. Effect size was calculated for each PROM at 3-year follow-up to quantify the size of the difference between both bearings. At 3-year follow-up, general linear mixed model analysis showed that there were no significant or clinically relevant differences between the two groups for all outcome measures. Calculated effect sizes were small (<0.3) for all the PROMs except for the FJS-12; these were moderate (0.5). The results of this study demonstrate that joint awareness was slightly lower in patients operated with the MB TKA with comparable improved clinical outcome and PROMs at 3-year follow-up. Measuring joint awareness with the FJS-12 is useful and provides more stringent information at 3-year follow-up compared to other PROMs and should be the PROM of choice at each follow-up after TKA. Level I, randomized controlled trial.

Method for enhancing the resolving power of ion mobility separations over a limited mobility range

DOEpatents

Shvartsburg, Alexandre A; Tang, Keqi; Smith, Richard D

2014-09-23

A method for raising the resolving power, specificity, and peak capacity of conventional ion mobility spectrometry is disclosed. Ions are separated in a dynamic electric field comprising an oscillatory field wave and opposing static field, or at least two counter propagating waves with different parameters (amplitude, profile, frequency, or speed). As the functional dependencies of mean drift velocity on the ion mobility in a wave and static field or in unequal waves differ, only single species is equilibrated while others drift in either direction and are mobility-separated. An ion mobility spectrum over a limited range is then acquired by measuring ion drift times through a fixed distance inside the gas-filled enclosure. The resolving power in the vicinity of equilibrium mobility substantially exceeds that for known traveling-wave or drift-tube IMS separations, with spectra over wider ranges obtainable by stitching multiple segments. The approach also enables low-cutoff, high-cutoff, and bandpass ion mobility filters.

Distributed Denial of Service Attack Source Detection Using Efficient Traceback Technique (ETT) in Cloud-Assisted Healthcare Environment.

PubMed

Latif, Rabia; Abbas, Haider; Latif, Seemab; Masood, Ashraf

2016-07-01

Security and privacy are the first and foremost concerns that should be given special attention when dealing with Wireless Body Area Networks (WBANs). As WBAN sensors operate in an unattended environment and carry critical patient health information, Distributed Denial of Service (DDoS) attack is one of the major attacks in WBAN environment that not only exhausts the available resources but also influence the reliability of information being transmitted. This research work is an extension of our previous work in which a machine learning based attack detection algorithm is proposed to detect DDoS attack in WBAN environment. However, in order to avoid complexity, no consideration was given to the traceback mechanism. During traceback, the challenge lies in reconstructing the attack path leading to identify the attack source. Among existing traceback techniques, Probabilistic Packet Marking (PPM) approach is the most commonly used technique in conventional IP- based networks. However, since marking probability assignment has significant effect on both the convergence time and performance of a scheme, it is not directly applicable in WBAN environment due to high convergence time and overhead on intermediate nodes. Therefore, in this paper we have proposed a new scheme called Efficient Traceback Technique (ETT) based on Dynamic Probability Packet Marking (DPPM) approach and uses MAC header in place of IP header. Instead of using fixed marking probability, the proposed scheme uses variable marking probability based on the number of hops travelled by a packet to reach the target node. Finally, path reconstruction algorithms are proposed to traceback an attacker. Evaluation and simulation results indicate that the proposed solution outperforms fixed PPM in terms of convergence time and computational overhead on nodes.

How crawler track-mounted conveyors improve bulk handling's economics

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

Hawkins, G.P.

1984-11-01

Crawler track-mounted conveyors can be used in most applications formerly requiring stacking, reclaiming or movement from excavators to bench conveyors. The crawler track-mounted conveyor has been automated for push button operation and allows mobilization of in-pit operations for the movement of overburden, minerals and coal. In-pit mobilization of crushers, the use of mobilized steep angle conveyor for the removal of coal from the pit, and the movement of overburden from excavation to spoil can all be done more economically when a combination of a crawler track mounted conveyor is used in conjunction with a shiftable or fixed conveyor.

Compression of facsimile graphics for transmission over digital mobile satellite circuits

NASA Astrophysics Data System (ADS)

Dimolitsas, Spiros; Corcoran, Frank L.

A technique for reducing the transmission requirements of facsimile images while maintaining high intelligibility in mobile communications environments is described. The algorithms developed are capable of achieving a compression of approximately 32 to 1. The technique focuses on the implementation of a low-cost interface unit suitable for facsimile communication between low-power mobile stations and fixed stations for both point-to-point and point-to-multipoint transmissions. This interface may be colocated with the transmitting facsimile terminals. The technique was implemented and tested by intercepting facsimile documents in a store-and-forward mode.

Models of Intracavity Frequency Doubled Lasers

DTIC Science & Technology

1990-01-01

Intermittency; Intermittency Theory; Entropies and Dimension with Intermittency; Resonances, Frobenius - Perron Operators and Power Spectra; and Scaling and...to finding a measure is to approximate the Frobenius - Perron operator, whose domain is the set of measures on M (see, e.g., Li, 1976). An invariant...measure of the system is a fixed point of the Frobenius - Perron operator, and an iterative method using this operator can be shown to converge to an

Higher-order finite-difference formulation of periodic Orbital-free Density Functional Theory

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

Ghosh, Swarnava; Suryanarayana, Phanish, E-mail: phanish.suryanarayana@ce.gatech.edu

2016-02-15

We present a real-space formulation and higher-order finite-difference implementation of periodic Orbital-free Density Functional Theory (OF-DFT). Specifically, utilizing a local reformulation of the electrostatic and kernel terms, we develop a generalized framework for performing OF-DFT simulations with different variants of the electronic kinetic energy. In particular, we propose a self-consistent field (SCF) type fixed-point method for calculations involving linear-response kinetic energy functionals. In this framework, evaluation of both the electronic ground-state and forces on the nuclei are amenable to computations that scale linearly with the number of atoms. We develop a parallel implementation of this formulation using the finite-difference discretization.more » We demonstrate that higher-order finite-differences can achieve relatively large convergence rates with respect to mesh-size in both the energies and forces. Additionally, we establish that the fixed-point iteration converges rapidly, and that it can be further accelerated using extrapolation techniques like Anderson's mixing. We validate the accuracy of the results by comparing the energies and forces with plane-wave methods for selected examples, including the vacancy formation energy in Aluminum. Overall, the suitability of the proposed formulation for scalable high performance computing makes it an attractive choice for large-scale OF-DFT calculations consisting of thousands of atoms.« less

An explicit solution to the exoatmospheric powered flight guidance and trajectory optimization problem for rocket propelled vehicles

NASA Technical Reports Server (NTRS)

Jaggers, R. F.

1977-01-01

A derivation of an explicit solution to the two point boundary-value problem of exoatmospheric guidance and trajectory optimization is presented. Fixed initial conditions and continuous burn, multistage thrusting are assumed. Any number of end conditions from one to six (throttling is required in the case of six) can be satisfied in an explicit and practically optimal manner. The explicit equations converge for off nominal conditions such as engine failure, abort, target switch, etc. The self starting, predictor/corrector solution involves no Newton-Rhapson iterations, numerical integration, or first guess values, and converges rapidly if physically possible. A form of this algorithm has been chosen for onboard guidance, as well as real time and preflight ground targeting and trajectory shaping for the NASA Space Shuttle Program.

Sharing criteria and performance standards for the 11.7-12.2 GHz band in region 2

NASA Technical Reports Server (NTRS)

1976-01-01

Possible criteria for sharing between the broadcasting-satellite and the fixed-satellite services are considered for each of several parameters in three categories: system, space station, and earth station. Criteria for sharing between the two satellite services and the three terrestrial services to which the 12-GHz band is allocated are discussed separately, first for the case of the fixed and mobile services and then for the broadcasting service.

Wireless Authentication Protocol Implementation: Descriptions of a Zero-Knowledge Proof (ZKP) Protocol Implementation for Testing on Ground and Airborne Mobile Networks

DTIC Science & Technology

2015-01-01

on AFRL’s small unmanned aerial vehicle (UAV) test bed . 15. SUBJECT TERMS Zero-Knowledge Proof Protocol Testing 16. SECURITY CLASSIFICATION OF...VERIFIER*** edition Version Information: Version 1.1.3 Version Details: Successful ZK authentication between two networked machines. Fixed a bug ...that causes intermittent bignum errors. Fixed a network hang bug and now allows continually authentication at the Verifier. Also now removing

Mobile communication devices causing interference in invasive and noninvasive ventilators.

PubMed

Dang, Bao P; Nel, Pierre R; Gjevre, John A

2007-06-01

The aim of this study was to assess if common mobile communication systems would cause significant interference on mechanical ventilation devices and at what distances would such interference occur. We tested all the invasive and noninvasive ventilatory devices used within our region. This consisted of 2 adult mechanical ventilators, 1 portable ventilator, 2 pediatric ventilators, and 2 noninvasive positive pressure ventilatory devices. We operated the mobile devices from the 2 cellular communication systems (digital) and 1 2-way radio system used in our province at varying distances from the ventilators and looked at any interference they created. We tested the 2-way radio system, which had a fixed operation power output of 3.0 watts, the Global Systems for Mobile Communication cellular system, which had a maximum power output of 2.0 watts and the Time Division Multiple Access cellular system, which had a maximum power output of 0.2 watts on our ventilators. The ventilators were ventilating a plastic lung at fixed settings. The mobile communication devices were tested at varying distances starting at zero meter from the ventilator and in all operation modes. The 2-way radio caused the most interference on some of the ventilators, but the maximum distance of interference was 1.0 m. The Global Systems for Mobile Communication system caused significant interference only at 0 m and minor interference at 0.5 m on only 1 ventilator. The Time Division Multiple Access system caused no interference at all. Significant interference consisted of a dramatic rise and fluctuation of the respiratory rate, pressure, and positive end-expiratory pressure of the ventilators with no normalization when the mobile device was removed. From our experiment on our ventilators with the communication systems used in our province, we conclude that mobile communication devices such as cellular phones and 2-way radios are safe and cause no interference unless operated at very close distances of less than 1 meter.

A Mobile Sensing Approach for Regional Surveillance of ...

EPA Pesticide Factsheets

This paper discusses plan-path and automated concepts for inspection to localize individual leaks and to quantify their source rates over regions with active oil and gas well pads and pipelines. This is a peer reviewed journal article submission that advances GMAP OTM 33 mobile measurement and fixed place fence line NGAM topics. This paper is focused on methods development and does not contain new or unpublished source emissions results regarding oil and gas.

Color engineering in the age of digital convergence

NASA Astrophysics Data System (ADS)

MacDonald, Lindsay W.

1998-09-01

Digital color imaging has developed over the past twenty years from specialized scientific applications into the mainstream of computing. In addition to the phenomenal growth of computer processing power and storage capacity, great advances have been made in the capabilities and cost-effectiveness of color imaging peripherals. The majority of imaging applications, including the graphic arts, video and film have made the transition from analogue to digital production methods. Digital convergence of computing, communications and television now heralds new possibilities for multimedia publishing and mobile lifestyles. Color engineering, the application of color science to the design of imaging products, is an emerging discipline that poses exciting challenges to the international color imaging community for training, research and standards.

Wireless inertial measurement unit with GPS (WIMU-GPS)--wearable monitoring platform for ecological assessment of lifespace and mobility in aging and disease.

PubMed

Boissy, Patrick; Brière, Simon; Hamel, Mathieu; Jog, Mandar; Speechley, Mark; Karelis, Antony; Frank, James; Vincent, Claude; Edwards, Rodrick; Duval, Christian

2011-01-01

This paper proposes an innovative ambulatory mobility and activity monitoring approach based on a wearable datalogging platform that combines inertial sensing with GPS tracking to assess the lifespace and mobility profile of individuals in their home and community environments. The components, I/O architecture, sensors and functions of the WIMU-GPS are presented. Outcome variables that can be measured with it are described and illustrated. Data on the power usage, operating autonomy of the WIMU-GPS and the GPS tracking performances and time to first fix of the unit are presented. The study of lifespace and mobility with the WIMU-GPS can potentially provide unique insights into intrapersonal and environmental factors contributing to mobility restriction. On-going studies are underway to establish the validity and reliability of the WIMU-GPS in characterizing the lifespace and mobility profile of older adults.

Constraint shapes convergence in tetrodotoxin-resistant sodium channels of snakes.

PubMed

Feldman, Chris R; Brodie, Edmund D; Brodie, Edmund D; Pfrender, Michael E

2012-03-20

Natural selection often produces convergent changes in unrelated lineages, but the degree to which such adaptations occur via predictable genetic paths is unknown. If only a limited subset of possible mutations is fixed in independent lineages, then it is clear that constraint in the production or function of molecular variants is an important determinant of adaptation. We demonstrate remarkably constrained convergence during the evolution of resistance to the lethal poison, tetrodotoxin, in six snake species representing three distinct lineages from around the globe. Resistance-conferring amino acid substitutions in a voltage-gated sodium channel, Na(v)1.4, are clustered in only two regions of the protein, and a majority of the replacements are confined to the same three positions. The observed changes represent only a small fraction of the experimentally validated mutations known to increase Na(v)1.4 resistance to tetrodotoxin. These results suggest that constraints resulting from functional tradeoffs between ion channel function and toxin resistance led to predictable patterns of evolutionary convergence at the molecular level. Our data are consistent with theoretical predictions and recent microcosm work that suggest a predictable path is followed during an adaptive walk along a mutational landscape, and that natural selection may be frequently constrained to produce similar genetic outcomes even when operating on independent lineages.

Better service, safer service : transit management for fixed-route systems

DOT National Transportation Integrated Search

1999-01-01

This brochure gives a brief overview of the different technologies available through advanced public transportation systems to aid public transit systems. It includes automatic vehicle location, mobile data terminals, and on-board surveillance.

Fractal: An Educational Model for the Convergence of Formal and Non-Formal Education

ERIC Educational Resources Information Center

Enríquez, Larisa

2017-01-01

For the last two decades, different authors have mentioned the need to have new pedagogies that respond better to current times, which are surrounded by a complex set of issues such as mobility, interculturality, curricular flexibility, accreditation and academic coverage. Fractal is an educational model proposal for online learning that is formed…

Adaptation of Human Resource Management and Industrial Relations Graduate Courses in Spain to the European Higher Education Area

ERIC Educational Resources Information Center

Barba-Sanchez, Virginia

2009-01-01

Europe's higher education system is currently undergoing a process of change and convergence in order to guarantee equal conditions for labour mobility within its borders. Spain, like any other European country, must adapt its legislation, homogenize its studies, and raise awareness among its educational institutions (beginning with their teaching…

Papier-mach(in)e: Thinking with "Sticky" Paper in the Cloud

ERIC Educational Resources Information Center

Enriquez-Gibson, Judith

2015-01-01

There is nothing less about paper and its use when it comes to academic study as we experience increasingly converging media spaces and functionalities of online applications within the screens of our laptops, mobile phones and tablet devices. The paper persists, and the paperless office, classroom and pedagogy become nothing but pure rhetoric.…

An appraisal of convergence failures in the application of logistic regression model in published manuscripts.

PubMed

Yusuf, O B; Bamgboye, E A; Afolabi, R F; Shodimu, M A

2014-09-01

Logistic regression model is widely used in health research for description and predictive purposes. Unfortunately, most researchers are sometimes not aware that the underlying principles of the techniques have failed when the algorithm for maximum likelihood does not converge. Young researchers particularly postgraduate students may not know why separation problem whether quasi or complete occurs, how to identify it and how to fix it. This study was designed to critically evaluate convergence issues in articles that employed logistic regression analysis published in an African Journal of Medicine and medical sciences between 2004 and 2013. Problems of quasi or complete separation were described and were illustrated with the National Demographic and Health Survey dataset. A critical evaluation of articles that employed logistic regression was conducted. A total of 581 articles was reviewed, of which 40 (6.9%) used binary logistic regression. Twenty-four (60.0%) stated the use of logistic regression model in the methodology while none of the articles assessed model fit. Only 3 (12.5%) properly described the procedures. Of the 40 that used the logistic regression model, the problem of convergence occurred in 6 (15.0%) of the articles. Logistic regression tends to be poorly reported in studies published between 2004 and 2013. Our findings showed that the procedure may not be well understood by researchers since very few described the process in their reports and may be totally unaware of the problem of convergence or how to deal with it.

A Newton-Krylov method with an approximate analytical Jacobian for implicit solution of Navier-Stokes equations on staggered overset-curvilinear grids with immersed boundaries.

PubMed

Asgharzadeh, Hafez; Borazjani, Iman

2017-02-15

The explicit and semi-implicit schemes in flow simulations involving complex geometries and moving boundaries suffer from time-step size restriction and low convergence rates. Implicit schemes can be used to overcome these restrictions, but implementing them to solve the Navier-Stokes equations is not straightforward due to their non-linearity. Among the implicit schemes for nonlinear equations, Newton-based techniques are preferred over fixed-point techniques because of their high convergence rate but each Newton iteration is more expensive than a fixed-point iteration. Krylov subspace methods are one of the most advanced iterative methods that can be combined with Newton methods, i.e., Newton-Krylov Methods (NKMs) to solve non-linear systems of equations. The success of NKMs vastly depends on the scheme for forming the Jacobian, e.g., automatic differentiation is very expensive, and matrix-free methods without a preconditioner slow down as the mesh is refined. A novel, computationally inexpensive analytical Jacobian for NKM is developed to solve unsteady incompressible Navier-Stokes momentum equations on staggered overset-curvilinear grids with immersed boundaries. Moreover, the analytical Jacobian is used to form preconditioner for matrix-free method in order to improve its performance. The NKM with the analytical Jacobian was validated and verified against Taylor-Green vortex, inline oscillations of a cylinder in a fluid initially at rest, and pulsatile flow in a 90 degree bend. The capability of the method in handling complex geometries with multiple overset grids and immersed boundaries is shown by simulating an intracranial aneurysm. It was shown that the NKM with an analytical Jacobian is 1.17 to 14.77 times faster than the fixed-point Runge-Kutta method, and 1.74 to 152.3 times (excluding an intensively stretched grid) faster than automatic differentiation depending on the grid (size) and the flow problem. In addition, it was shown that using only the diagonal of the Jacobian further improves the performance by 42 - 74% compared to the full Jacobian. The NKM with an analytical Jacobian showed better performance than the fixed point Runge-Kutta because it converged with higher time steps and in approximately 30% less iterations even when the grid was stretched and the Reynold number was increased. In fact, stretching the grid decreased the performance of all methods, but the fixed-point Runge-Kutta performance decreased 4.57 and 2.26 times more than NKM with a diagonal Jacobian when the stretching factor was increased, respectively. The NKM with a diagonal analytical Jacobian and matrix-free method with an analytical preconditioner are the fastest methods and the superiority of one to another depends on the flow problem. Furthermore, the implemented methods are fully parallelized with parallel efficiency of 80-90% on the problems tested. The NKM with the analytical Jacobian can guide building preconditioners for other techniques to improve their performance in the future.

A Newton–Krylov method with an approximate analytical Jacobian for implicit solution of Navier–Stokes equations on staggered overset-curvilinear grids with immersed boundaries

PubMed Central

Asgharzadeh, Hafez; Borazjani, Iman

2016-01-01

The explicit and semi-implicit schemes in flow simulations involving complex geometries and moving boundaries suffer from time-step size restriction and low convergence rates. Implicit schemes can be used to overcome these restrictions, but implementing them to solve the Navier-Stokes equations is not straightforward due to their non-linearity. Among the implicit schemes for nonlinear equations, Newton-based techniques are preferred over fixed-point techniques because of their high convergence rate but each Newton iteration is more expensive than a fixed-point iteration. Krylov subspace methods are one of the most advanced iterative methods that can be combined with Newton methods, i.e., Newton-Krylov Methods (NKMs) to solve non-linear systems of equations. The success of NKMs vastly depends on the scheme for forming the Jacobian, e.g., automatic differentiation is very expensive, and matrix-free methods without a preconditioner slow down as the mesh is refined. A novel, computationally inexpensive analytical Jacobian for NKM is developed to solve unsteady incompressible Navier-Stokes momentum equations on staggered overset-curvilinear grids with immersed boundaries. Moreover, the analytical Jacobian is used to form preconditioner for matrix-free method in order to improve its performance. The NKM with the analytical Jacobian was validated and verified against Taylor-Green vortex, inline oscillations of a cylinder in a fluid initially at rest, and pulsatile flow in a 90 degree bend. The capability of the method in handling complex geometries with multiple overset grids and immersed boundaries is shown by simulating an intracranial aneurysm. It was shown that the NKM with an analytical Jacobian is 1.17 to 14.77 times faster than the fixed-point Runge-Kutta method, and 1.74 to 152.3 times (excluding an intensively stretched grid) faster than automatic differentiation depending on the grid (size) and the flow problem. In addition, it was shown that using only the diagonal of the Jacobian further improves the performance by 42 – 74% compared to the full Jacobian. The NKM with an analytical Jacobian showed better performance than the fixed point Runge-Kutta because it converged with higher time steps and in approximately 30% less iterations even when the grid was stretched and the Reynold number was increased. In fact, stretching the grid decreased the performance of all methods, but the fixed-point Runge-Kutta performance decreased 4.57 and 2.26 times more than NKM with a diagonal Jacobian when the stretching factor was increased, respectively. The NKM with a diagonal analytical Jacobian and matrix-free method with an analytical preconditioner are the fastest methods and the superiority of one to another depends on the flow problem. Furthermore, the implemented methods are fully parallelized with parallel efficiency of 80–90% on the problems tested. The NKM with the analytical Jacobian can guide building preconditioners for other techniques to improve their performance in the future. PMID:28042172

A Newton-Krylov method with an approximate analytical Jacobian for implicit solution of Navier-Stokes equations on staggered overset-curvilinear grids with immersed boundaries

NASA Astrophysics Data System (ADS)

Asgharzadeh, Hafez; Borazjani, Iman

2017-02-01

The explicit and semi-implicit schemes in flow simulations involving complex geometries and moving boundaries suffer from time-step size restriction and low convergence rates. Implicit schemes can be used to overcome these restrictions, but implementing them to solve the Navier-Stokes equations is not straightforward due to their non-linearity. Among the implicit schemes for non-linear equations, Newton-based techniques are preferred over fixed-point techniques because of their high convergence rate but each Newton iteration is more expensive than a fixed-point iteration. Krylov subspace methods are one of the most advanced iterative methods that can be combined with Newton methods, i.e., Newton-Krylov Methods (NKMs) to solve non-linear systems of equations. The success of NKMs vastly depends on the scheme for forming the Jacobian, e.g., automatic differentiation is very expensive, and matrix-free methods without a preconditioner slow down as the mesh is refined. A novel, computationally inexpensive analytical Jacobian for NKM is developed to solve unsteady incompressible Navier-Stokes momentum equations on staggered overset-curvilinear grids with immersed boundaries. Moreover, the analytical Jacobian is used to form a preconditioner for matrix-free method in order to improve its performance. The NKM with the analytical Jacobian was validated and verified against Taylor-Green vortex, inline oscillations of a cylinder in a fluid initially at rest, and pulsatile flow in a 90 degree bend. The capability of the method in handling complex geometries with multiple overset grids and immersed boundaries is shown by simulating an intracranial aneurysm. It was shown that the NKM with an analytical Jacobian is 1.17 to 14.77 times faster than the fixed-point Runge-Kutta method, and 1.74 to 152.3 times (excluding an intensively stretched grid) faster than automatic differentiation depending on the grid (size) and the flow problem. In addition, it was shown that using only the diagonal of the Jacobian further improves the performance by 42-74% compared to the full Jacobian. The NKM with an analytical Jacobian showed better performance than the fixed point Runge-Kutta because it converged with higher time steps and in approximately 30% less iterations even when the grid was stretched and the Reynold number was increased. In fact, stretching the grid decreased the performance of all methods, but the fixed-point Runge-Kutta performance decreased 4.57 and 2.26 times more than NKM with a diagonal and full Jacobian, respectivley, when the stretching factor was increased. The NKM with a diagonal analytical Jacobian and matrix-free method with an analytical preconditioner are the fastest methods and the superiority of one to another depends on the flow problem. Furthermore, the implemented methods are fully parallelized with parallel efficiency of 80-90% on the problems tested. The NKM with the analytical Jacobian can guide building preconditioners for other techniques to improve their performance in the future.

Use of mobile and passive badge air monitoring data for NOX and ozone air pollution spatial exposure prediction models.

PubMed

Xu, Wei; Riley, Erin A; Austin, Elena; Sasakura, Miyoko; Schaal, Lanae; Gould, Timothy R; Hartin, Kris; Simpson, Christopher D; Sampson, Paul D; Yost, Michael G; Larson, Timothy V; Xiu, Guangli; Vedal, Sverre

2017-03-01

Air pollution exposure prediction models can make use of many types of air monitoring data. Fixed location passive samples typically measure concentrations averaged over several days to weeks. Mobile monitoring data can generate near continuous concentration measurements. It is not known whether mobile monitoring data are suitable for generating well-performing exposure prediction models or how they compare with other types of monitoring data in generating exposure models. Measurements from fixed site passive samplers and mobile monitoring platform were made over a 2-week period in Baltimore in the summer and winter months in 2012. Performance of exposure prediction models for long-term nitrogen oxides (NO X ) and ozone (O 3 ) concentrations were compared using a state-of-the-art approach for model development based on land use regression (LUR) and geostatistical smoothing. Model performance was evaluated using leave-one-out cross-validation (LOOCV). Models performed well using the mobile peak traffic monitoring data for both NO X and O 3 , with LOOCV R 2 s of 0.70 and 0.71, respectively, in the summer, and 0.90 and 0.58, respectively, in the winter. Models using 2-week passive samples for NO X had LOOCV R 2 s of 0.60 and 0.65 in the summer and winter months, respectively. The passive badge sampling data were not adequate for developing models for O 3 . Mobile air monitoring data can be used to successfully build well-performing LUR exposure prediction models for NO X and O 3 and are a better source of data for these models than 2-week passive badge data.

Dynamics of the near response under natural viewing conditions with an open-view sensor

PubMed Central

Chirre, Emmanuel; Prieto, Pedro; Artal, Pablo

2015-01-01

We have studied the temporal dynamics of the near response (accommodation, convergence and pupil constriction) in healthy subjects when accommodation was performed under natural binocular and monocular viewing conditions. A binocular open-view multi-sensor based on an invisible infrared Hartmann-Shack sensor was used for non-invasive measurements of both eyes simultaneously in real time at 25Hz. Response times for each process under different conditions were measured. The accommodative responses for binocular vision were faster than for monocular conditions. When one eye was blocked, accommodation and convergence were triggered simultaneously and synchronized, despite the fact that no retinal disparity was available. We found that upon the onset of the near target, the unblocked eye rapidly changes its line of sight to fix it on the stimulus while the blocked eye moves in the same direction, producing the equivalent to a saccade, but then converges to the (blocked) target in synchrony with accommodation. This open-view instrument could be further used for additional experiments with other tasks and conditions. PMID:26504666

A High-Order Low-Order Algorithm with Exponentially Convergent Monte Carlo for Thermal Radiative Transfer

DOE PAGES

Bolding, Simon R.; Cleveland, Mathew Allen; Morel, Jim E.

2016-10-21

In this paper, we have implemented a new high-order low-order (HOLO) algorithm for solving thermal radiative transfer problems. The low-order (LO) system is based on the spatial and angular moments of the transport equation and a linear-discontinuous finite-element spatial representation, producing equations similar to the standard S 2 equations. The LO solver is fully implicit in time and efficiently resolves the nonlinear temperature dependence at each time step. The high-order (HO) solver utilizes exponentially convergent Monte Carlo (ECMC) to give a globally accurate solution for the angular intensity to a fixed-source pure-absorber transport problem. This global solution is used tomore » compute consistency terms, which require the HO and LO solutions to converge toward the same solution. The use of ECMC allows for the efficient reduction of statistical noise in the Monte Carlo solution, reducing inaccuracies introduced through the LO consistency terms. Finally, we compare results with an implicit Monte Carlo code for one-dimensional gray test problems and demonstrate the efficiency of ECMC over standard Monte Carlo in this HOLO algorithm.« less

Accelerated perturbation-resilient block-iterative projection methods with application to image reconstruction

PubMed Central

Nikazad, T; Davidi, R; Herman, G. T.

2013-01-01

We study the convergence of a class of accelerated perturbation-resilient block-iterative projection methods for solving systems of linear equations. We prove convergence to a fixed point of an operator even in the presence of summable perturbations of the iterates, irrespective of the consistency of the linear system. For a consistent system, the limit point is a solution of the system. In the inconsistent case, the symmetric version of our method converges to a weighted least squares solution. Perturbation resilience is utilized to approximate the minimum of a convex functional subject to the equations. A main contribution, as compared to previously published approaches to achieving similar aims, is a more than an order of magnitude speed-up, as demonstrated by applying the methods to problems of image reconstruction from projections. In addition, the accelerated algorithms are illustrated to be better, in a strict sense provided by the method of statistical hypothesis testing, than their unaccelerated versions for the task of detecting small tumors in the brain from X-ray CT projection data. PMID:23440911

Accelerated perturbation-resilient block-iterative projection methods with application to image reconstruction.

PubMed

Nikazad, T; Davidi, R; Herman, G T

2012-03-01

We study the convergence of a class of accelerated perturbation-resilient block-iterative projection methods for solving systems of linear equations. We prove convergence to a fixed point of an operator even in the presence of summable perturbations of the iterates, irrespective of the consistency of the linear system. For a consistent system, the limit point is a solution of the system. In the inconsistent case, the symmetric version of our method converges to a weighted least squares solution. Perturbation resilience is utilized to approximate the minimum of a convex functional subject to the equations. A main contribution, as compared to previously published approaches to achieving similar aims, is a more than an order of magnitude speed-up, as demonstrated by applying the methods to problems of image reconstruction from projections. In addition, the accelerated algorithms are illustrated to be better, in a strict sense provided by the method of statistical hypothesis testing, than their unaccelerated versions for the task of detecting small tumors in the brain from X-ray CT projection data.

Prediction of Individual Social-Demographic Role Based on Travel Behavior Variability Using Long-Term GPS Data

DOE PAGES

Zhu, Lei; Gonder, Jeffrey; Lin, Lei

2017-08-16

With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variabilitymore » describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. In conclusion, the sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.« less

Prediction of Individual Social-Demographic Role Based on Travel Behavior Variability Using Long-Term GPS Data

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

Zhu, Lei; Gonder, Jeffrey; Lin, Lei

With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variabilitymore » describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. In conclusion, the sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.« less

Modeling and optimization of Quality of Service routing in Mobile Ad hoc Networks

NASA Astrophysics Data System (ADS)

Rafsanjani, Marjan Kuchaki; Fatemidokht, Hamideh; Balas, Valentina Emilia

2016-01-01

Mobile ad hoc networks (MANETs) are a group of mobile nodes that are connected without using a fixed infrastructure. In these networks, nodes communicate with each other by forming a single-hop or multi-hop network. To design effective mobile ad hoc networks, it is important to evaluate the performance of multi-hop paths. In this paper, we present a mathematical model for a routing protocol under energy consumption and packet delivery ratio of multi-hop paths. In this model, we use geometric random graphs rather than random graphs. Our proposed model finds effective paths that minimize the energy consumption and maximizes the packet delivery ratio of the network. Validation of the mathematical model is performed through simulation.

A model for the distribution of watermarked digital content on mobile networks

NASA Astrophysics Data System (ADS)

Frattolillo, Franco; D'Onofrio, Salvatore

2006-10-01

Although digital watermarking can be considered one of the key technologies to implement the copyright protection of digital contents distributed on the Internet, most of the content distribution models based on watermarking protocols proposed in literature have been purposely designed for fixed networks and cannot be easily adapted to mobile networks. On the contrary, the use of mobile devices currently enables new types of services and business models, and this makes the development of new content distribution models for mobile environments strategic in the current scenario of the Internet. This paper presents and discusses a distribution model of watermarked digital contents for such environments able to achieve a trade-off between the needs of efficiency and security.

MSAT system and service description

NASA Astrophysics Data System (ADS)

Sward, D. J.; Lok, M. F.

1986-09-01

A satellite based mobile communications system known as MSAT, was developed in Canada. It will be used primarily in rural and remote regions where the wide-area coverage and extended range features are of greatest benefit. Applications can be found in trucking, mineral exploration, forestry, law enforcement, coastal and in-land shipping, light aircraft communications, national paging, environmental sensing, remote monitoring and control of utilities, and emergency relief. The services which are likely to be offered initially on MSAT include mobile radio, mobile telephone, mobile data, wide-area paging, supervisory control, and data collection. Maritime and aeronautical services can also be provided as well as conventional telephone service to locations which for technical and economic reasons cannot be served by the fixed terrestrial and satellite infrastructures.

Towards the development of tamper-resistant, ground-based mobile sensor nodes

NASA Astrophysics Data System (ADS)

Mascarenas, David; Stull, Christopher; Farrar, Charles

2011-11-01

Mobile sensor nodes hold great potential for collecting field data using fewer resources than human operators would require and potentially requiring fewer sensors than a fixed-position sensor array. It would be very beneficial to allow these mobile sensor nodes to operate unattended with a minimum of human intervention. In order to allow mobile sensor nodes to operate unattended in a field environment, it is imperative that they be capable of identifying and responding to external agents that may attempt to tamper with, damage or steal the mobile sensor nodes, while still performing their data collection mission. Potentially hostile external agents could include animals, other mobile sensor nodes, or humans. This work will focus on developing control policies to help enable a mobile sensor node to identify and avoid capture by a hostile un-mounted human. The work is developed in a simulation environment, and demonstrated using a non-holonomic, ground-based mobile sensor node. This work will be a preliminary step toward ensuring the cyber-physical security of ground-based mobile sensor nodes that operate unattended in potentially unfriendly environments.

Social Properties of Mobile Video

NASA Astrophysics Data System (ADS)

Mitchell, April Slayden; O'Hara, Kenton; Vorbau, Alex

Mobile video is now an everyday possibility with a wide array of commercially available devices, services, and content. These new technologies have created dramatic shifts in the way video-based media can be produced, consumed, and delivered by people beyond the familiar behaviors associated with fixed TV and video technologies. Such technology revolutions change the way users behave and change their expectations in regards to their mobile video experiences. Building upon earlier studies of mobile video, this paper reports on a study using diary techniques and ethnographic interviews to better understand how people are using commercially available mobile video technologies in their everyday lives. Drawing on reported episodes of mobile video behavior, the study identifies the social motivations and values underpinning these behaviors that help characterize mobile video consumption beyond the simplistic notion of viewing video only to kill time. This paper also discusses the significance of user-generated content and the usage of video in social communities through the description of two mobile video technology services that allow users to create and share content. Implications for adoption and design of mobile video technologies and services are discussed as well.

An approach to efficient mobility management in intelligent networks

NASA Technical Reports Server (NTRS)

Murthy, K. M. S.

1995-01-01

Providing personal communication systems supporting full mobility require intelligent networks for tracking mobile users and facilitating outgoing and incoming calls over different physical and network environments. In realizing the intelligent network functionalities, databases play a major role. Currently proposed network architectures envision using the SS7-based signaling network for linking these DB's and also for interconnecting DB's with switches. If the network has to support ubiquitous, seamless mobile services, then it has to support additionally mobile application parts, viz., mobile origination calls, mobile destination calls, mobile location updates and inter-switch handovers. These functions will generate significant amount of data and require them to be transferred between databases (HLR, VLR) and switches (MSC's) very efficiently. In the future, the users (fixed or mobile) may use and communicate with sophisticated CPE's (e.g. multimedia, multipoint and multisession calls) which may require complex signaling functions. This will generate volumness service handling data and require efficient transfer of these message between databases and switches. Consequently, the network providers would be able to add new services and capabilities to their networks incrementally, quickly and cost-effectively.

An economic analysis of mobile pyrolysis for northern New Mexico forests.

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

Brady, Patrick D.; Brown, Alexander L.; Mowry, Curtis Dale

2011-12-01

In the interest of providing an economically sensible use for the copious small-diameter wood in Northern New Mexico, an economic study is performed focused on mobile pyrolysis. Mobile pyrolysis was selected for the study because transportation costs limit the viability of a dedicated pyrolysis plant, and the relative simplicity of pyrolysis compared to other technology solutions lends itself to mobile reactor design. A bench-scale pyrolysis system was used to study the wood pyrolysis process and to obtain performance data that was otherwise unavailable under conditions theorized to be optimal given the regional problem. Pyrolysis can convert wood to three mainmore » products: fixed gases, liquid pyrolysis oil and char. The fixed gases are useful as low-quality fuel, and may have sufficient chemical energy to power a mobile system, eliminating the need for an external power source. The majority of the energy content of the pyrolysis gas is associated with carbon monoxide, followed by light hydrocarbons. The liquids are well characterized in the historical literature, and have slightly lower heating values comparable to the feedstock. They consist of water and a mix of hundreds of hydrocarbons, and are acidic. They are also unstable, increasing in viscosity with time stored. Up to 60% of the biomass in bench-scale testing was converted to liquids. Lower ({approx}550 C) furnace temperatures are preferred because of the decreased propensity for deposits and the high liquid yields. A mobile pyrolysis system would be designed with low maintenance requirements, should be able to access wilderness areas, and should not require more than one or two people to operate the system. The techno-economic analysis assesses fixed and variable costs. It suggests that the economy of scale is an important factor, as higher throughput directly leads to improved system economic viability. Labor and capital equipment are the driving factors in the viability of the system. The break-even selling price for the baseline assumption is about $11/GJ, however it may be possible to reduce this value by 20-30% depending on other factors evaluated in the non-baseline scenarios. Assuming a value for the char co-product improves the analysis. Significantly lower break-even costs are possible in an international setting, as labor is the dominant production cost.« less

Premature Ventricular Contraction Coupling Interval Variability Destabilizes Cardiac Neuronal and Electrophysiological Control: Insights From Simultaneous Cardioneural Mapping.

PubMed

Hamon, David; Rajendran, Pradeep S; Chui, Ray W; Ajijola, Olujimi A; Irie, Tadanobu; Talebi, Ramin; Salavatian, Siamak; Vaseghi, Marmar; Bradfield, Jason S; Armour, J Andrew; Ardell, Jeffrey L; Shivkumar, Kalyanam

2017-04-01

Variability in premature ventricular contraction (PVC) coupling interval (CI) increases the risk of cardiomyopathy and sudden death. The autonomic nervous system regulates cardiac electrical and mechanical indices, and its dysregulation plays an important role in cardiac disease pathogenesis. The impact of PVCs on the intrinsic cardiac nervous system, a neural network on the heart, remains unknown. The objective was to determine the effect of PVCs and CI on intrinsic cardiac nervous system function in generating cardiac neuronal and electric instability using a novel cardioneural mapping approach. In a porcine model (n=8), neuronal activity was recorded from a ventricular ganglion using a microelectrode array, and cardiac electrophysiological mapping was performed. Neurons were functionally classified based on their response to afferent and efferent cardiovascular stimuli, with neurons that responded to both defined as convergent (local reflex processors). Dynamic changes in neuronal activity were then evaluated in response to right ventricular outflow tract PVCs with fixed short, fixed long, and variable CI. PVC delivery elicited a greater neuronal response than all other stimuli ( P <0.001). Compared with fixed short and long CI, PVCs with variable CI had a greater impact on neuronal response ( P <0.05 versus short CI), particularly on convergent neurons ( P <0.05), as well as neurons receiving sympathetic ( P <0.05) and parasympathetic input ( P <0.05). The greatest cardiac electric instability was also observed after variable (short) CI PVCs. Variable CI PVCs affect critical populations of intrinsic cardiac nervous system neurons and alter cardiac repolarization. These changes may be critical for arrhythmogenesis and remodeling, leading to cardiomyopathy. © 2017 American Heart Association, Inc.

Premature Ventricular Contraction Coupling Interval Variability Destabilizes Cardiac Neuronal and Electrophysiological Control: Insights from Simultaneous Cardio-Neural Mapping

PubMed Central

Hamon, David; Rajendran, Pradeep S.; Chui, Ray W.; Ajijola, Olujimi A.; Irie, Tadanobu; Talebi, Ramin; Salavatian, Siamak; Vaseghi, Marmar; Bradfield, Jason S.; Armour, J. Andrew; Ardell, Jeffrey L.; Shivkumar, Kalyanam

2017-01-01

Background Variability in premature ventricular contraction (PVC) coupling interval (CI) increases the risk of cardiomyopathy and sudden death. The autonomic nervous system regulates cardiac electrical and mechanical indices, and its dysregulation plays an important role in cardiac disease pathogenesis. The impact of PVCs on the intrinsic cardiac nervous system (ICNS), a neural network on the heart, remains unknown. The objective was to determine the effect of PVCs and CI on ICNS function in generating cardiac neuronal and electrical instability using a novel cardio-neural mapping approach. Methods and Results In a porcine model (n=8) neuronal activity was recorded from a ventricular ganglion using a microelectrode array, and cardiac electrophysiological mapping was performed. Neurons were functionally classified based on their response to afferent and efferent cardiovascular stimuli, with neurons that responded to both defined as convergent (local reflex processors). Dynamic changes in neuronal activity were then evaluated in response to right ventricular outflow tract PVCs with fixed short, fixed long, and variable CI. PVC delivery elicited a greater neuronal response than all other stimuli (P<0.001). Compared to fixed short and long CI, PVCs with variable CI had a greater impact on neuronal response (P<0.05 versus short CI), particularly on convergent neurons (P<0.05), as well as neurons receiving sympathetic (P<0.05) and parasympathetic input (P<0.05). The greatest cardiac electrical instability was also observed following variable (short) CI PVCs. Conclusions Variable CI PVCs affect critical populations of ICNS neurons and alter cardiac repolarization. These changes may be critical for arrhythmogenesis and remodeling leading to cardiomyopathy. PMID:28408652

Corruption of accuracy and efficiency of Markov chain Monte Carlo simulation by inaccurate numerical implementation of conceptual hydrologic models

NASA Astrophysics Data System (ADS)

Schoups, G.; Vrugt, J. A.; Fenicia, F.; van de Giesen, N. C.

2010-10-01

Conceptual rainfall-runoff models have traditionally been applied without paying much attention to numerical errors induced by temporal integration of water balance dynamics. Reliance on first-order, explicit, fixed-step integration methods leads to computationally cheap simulation models that are easy to implement. Computational speed is especially desirable for estimating parameter and predictive uncertainty using Markov chain Monte Carlo (MCMC) methods. Confirming earlier work of Kavetski et al. (2003), we show here that the computational speed of first-order, explicit, fixed-step integration methods comes at a cost: for a case study with a spatially lumped conceptual rainfall-runoff model, it introduces artificial bimodality in the marginal posterior parameter distributions, which is not present in numerically accurate implementations of the same model. The resulting effects on MCMC simulation include (1) inconsistent estimates of posterior parameter and predictive distributions, (2) poor performance and slow convergence of the MCMC algorithm, and (3) unreliable convergence diagnosis using the Gelman-Rubin statistic. We studied several alternative numerical implementations to remedy these problems, including various adaptive-step finite difference schemes and an operator splitting method. Our results show that adaptive-step, second-order methods, based on either explicit finite differencing or operator splitting with analytical integration, provide the best alternative for accurate and efficient MCMC simulation. Fixed-step or adaptive-step implicit methods may also be used for increased accuracy, but they cannot match the efficiency of adaptive-step explicit finite differencing or operator splitting. Of the latter two, explicit finite differencing is more generally applicable and is preferred if the individual hydrologic flux laws cannot be integrated analytically, as the splitting method then loses its advantage.

Fixed interface charges between AlGaN barrier and gate stack composed of in situ grown SiN and Al{sub 2}O{sub 3} in AlGaN/GaN high electron mobility transistors with normally off capability

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

Capriotti, M., E-mail: mattia.capriotti@tuwien.ac.at; Alexewicz, A.; Fleury, C.

2014-03-17

Using a generalized extraction method, the fixed charge density N{sub int} at the interface between in situ deposited SiN and 5 nm thick AlGaN barrier is evaluated by measurements of threshold voltage V{sub th} of an AlGaN/GaN metal insulator semiconductor high electron mobility transistor as a function of SiN thickness. The thickness of the originally deposited 50 nm thick SiN layer is reduced by dry etching. The extracted N{sub int} is in the order of the AlGaN polarization charge density. The total removal of the in situ SiN cap leads to a complete depletion of the channel region resulting in V{sub th} = +1 V.more » Fabrication of a gate stack with Al{sub 2}O{sub 3} as a second cap layer, deposited on top of the in situ SiN, is not introducing additional fixed charges at the SiN/Al{sub 2}O{sub 3} interface.« less

Posterior stability in fixed-bearing versus mobile-bearing total knee replacement: a radiological comparison of two implants.

PubMed

Siebold, R; Louisia, S; Canty, J; Bartlett, R J

2007-02-01

Posterior tibial translation in total knee replacement (TKR) could be one major factor for PE wear, delamination and loosening of the tibial component due to increased shear forces and component-to-bone interface stress. The aim of this study was to assess the posterior stability of two different designs of posterior cruciate ligament (PCL) substituting TKR. In this non-randomised consecutive study 43 patients underwent TKR for primary osteoarthritis. Twenty-six patients in group FB received a deep-dished fixed-bearing Duracon TKR (Howmedica, Rutherford, NJ, USA) and 17 patients in group MB a deep-dished rotating mobile-bearing Duracon TKR. In both groups the PCL was resected. All patients had pre- and postoperative kneeling stress radiographs and were clinically evaluated with the Knee Society Score. Posterior tibial translation was measured by tracing a line along the posterior tibial cortex in relationship to the posterior edge of Blumensaat's line. The average follow-up was 13 months for group FB and 11 months for group MB. Both groups demonstrated a statistical significant increase of the mean posterior tibial translation on kneeling stress X-ray of 4.1 mm (group FB) (P < 0.001) and of 6.6 mm (group MB) (P < 0.001) compared to pre-operative. Group MB showed a significant higher posterior draw (P < 0.008). Clinical assessment using the Knee Society Score showed comparable short-term results. The deep-dished fixed-bearing TKR as well as the deep-dished rotating mobile-bearing TKR demonstrated significant posterior tibial translation on kneeling stress X-ray. It remains to be determined what amount of joint play is optimal for clinical function and to minimise shear forces and PE wear. Moreover the amount of posterior tibial translation was significantly higher with the mobile-bearing insert, which could be directly related to the asymmetric rotational mobility of the tibial insert. A long-term follow-up is necessary to investigate whether our findings correlate with the survival-rate of these specific implants.

Three-dimensional esthetic analysis in treatment planning for implant-supported fixed prosthesis in the edentulous maxilla: review of the esthetics literature.

PubMed

Bidra, Avinash S

2011-08-01

Fixed implant-supported prosthesis for the edentulous maxilla has gained tremendous popularity over the years. Multiple prosthetic designs have been introduced in order to accommodate a gamut of clinical situations. Irrespective of the design, it is paramount that the esthetics imparted by the prosthesis be uncompromised. Though esthetics is subjective, a common ground exists where all its fundamental principles converge. This article reviews pertinent dental and facial esthetics literature for application of various esthetic concepts involved in diagnosis and treatment planning for an implant-supported fixed prosthesis in the edentulous maxilla. Three-dimensional esthetic analysis involves assessment of various esthetic parameters in superior-inferior, medial-lateral, and anterior-posterior dimensions. The impact of various esthetic parameters such as facial forms, facial profiles, maxillary teeth positions, maxillary teeth proportions, smile lines, lip support, gingival display, facial midline, dental midline, horizontal cant, and smile width are discussed in detail. © 2011 Wiley Periodicals, Inc.

Renormalization-group theory for finite-size scaling in extreme statistics

NASA Astrophysics Data System (ADS)

Györgyi, G.; Moloney, N. R.; Ozogány, K.; Rácz, Z.; Droz, M.

2010-04-01

We present a renormalization-group (RG) approach to explain universal features of extreme statistics applied here to independent identically distributed variables. The outlines of the theory have been described in a previous paper, the main result being that finite-size shape corrections to the limit distribution can be obtained from a linearization of the RG transformation near a fixed point, leading to the computation of stable perturbations as eigenfunctions. Here we show details of the RG theory which exhibit remarkable similarities to the RG known in statistical physics. Besides the fixed points explaining universality, and the least stable eigendirections accounting for convergence rates and shape corrections, the similarities include marginally stable perturbations which turn out to be generic for the Fisher-Tippett-Gumbel class. Distribution functions containing unstable perturbations are also considered. We find that, after a transitory divergence, they return to the universal fixed line at the same or at a different point depending on the type of perturbation.

47 CFR 95.29 - Channels available.

Code of Federal Regulations, 2011 CFR

2011-10-01

....6750, 462.7000 and 462.7250. (b) For a mobile station, control station, or fixed station operated in... population as defined in the U.S. Census of Population, 1960, Vol. 1, Table 23, page 50 that were authorized...

47 CFR 95.29 - Channels available.

Code of Federal Regulations, 2014 CFR

2014-10-01

....6750, 462.7000 and 462.7250. (b) For a mobile station, control station, or fixed station operated in... population as defined in the U.S. Census of Population, 1960, Vol. 1, Table 23, page 50 that were authorized...

47 CFR 95.29 - Channels available.

Code of Federal Regulations, 2013 CFR

2013-10-01

....6750, 462.7000 and 462.7250. (b) For a mobile station, control station, or fixed station operated in... population as defined in the U.S. Census of Population, 1960, Vol. 1, Table 23, page 50 that were authorized...

The influence of interactions between accommodation and convergence on the lag of accommodation.

PubMed

Schor, C

1999-03-01

Several models of myopia predict that growth of axial length is stimulated by blur. Accommodative lag has been suggested as an important source of blur in the development of myopia and this study has modeled how cross-link interactions between accommodation and convergence might interact with uncorrected distance heterophoria and refractive error to influence accommodative lag. Accommodative lag was simulated with two models of interactions between accommodation and convergence (one with and one without adaptable tonic elements). Simulations of both models indicate that both uncorrected hyperopia and esophoria increase the lag of accommodative and uncorrected myopia and exophoria decrease the lag or introduce a lead of accommodation in response to the near (40 cm) stimulus. These effects were increased when gain of either cross-link, accommodative convergence (AC/A) or convergence accommodation (CA/C), was increased within a moderate range of values while the other was fixed at a normal value (clamped condition). These effects were exaggerated when both the AC/A and CA/C ratios were increased (covaried condition) and affects of cross-link gain were negated when an increase of one cross-link (e.g. AC/A) was accompanied by a reduction of the other cross-link (e.g. CA/C) (reciprocal condition). The inclusion of tonic adaptation in the model reduced steady state errors of accommodation for all conditions except when the AC/A ratio was very high (2 MA/D). Combinations of cross-link interactions between accommodation and convergence that resemble either clamped or reciprocal patterns occur naturally in clinical populations. Simulations suggest that these two patterns of abnormal cross-link interactions could affect the progression of myopia differently. Adaptable tonic accommodation and tonic vergence could potentially reduce the progression of myopia by reducing the lag of accommodation.

An analysis of the convergence of Newton iterations for solving elliptic Kepler's equation

NASA Astrophysics Data System (ADS)

Elipe, A.; Montijano, J. I.; Rández, L.; Calvo, M.

2017-12-01

In this note a study of the convergence properties of some starters E_0 = E_0(e,M) in the eccentricity-mean anomaly variables for solving the elliptic Kepler's equation (KE) by Newton's method is presented. By using a Wang Xinghua's theorem (Xinghua in Math Comput 68(225):169-186, 1999) on best possible error bounds in the solution of nonlinear equations by Newton's method, we obtain for each starter E_0(e,M) a set of values (e,M) \\in [0, 1) × [0, π ] that lead to the q-convergence in the sense that Newton's sequence (E_n)_{n ≥ 0} generated from E_0 = E_0(e,M) is well defined, converges to the exact solution E^* = E^*(e,M) of KE and further \\vert E_n - E^* \\vert ≤ q^{2^n -1} \\vert E_0 - E^* \\vert holds for all n ≥ 0. This study completes in some sense the results derived by Avendaño et al. (Celest Mech Dyn Astron 119:27-44, 2014) by using Smale's α -test with q=1/2. Also since in KE the convergence rate of Newton's method tends to zero as e → 0, we show that the error estimates given in the Wang Xinghua's theorem for KE can also be used to determine sets of q-convergence with q = e^k \\widetilde{q} for all e \\in [0,1) and a fixed \\widetilde{q} ≤ 1. Some remarks on the use of this theorem to derive a priori estimates of the error \\vert E_n - E^* \\vert after n Kepler's iterations are given. Finally, a posteriori bounds of this error that can be used to a dynamical estimation of the error are also obtained.

Design of a mobile hydrological data measurement system

NASA Astrophysics Data System (ADS)

Liu, Yunping; Wang, Tianmiao; Dai, Fenfen

2017-06-01

The current hydrological data acquisition is mainly used in the instrument measurement. Instrument measurement equipment is mainly fixed in a certain water area and the device is easy to be lost. In view of a series of problems, the dynamic measurement system is established by the method of unmanned surface vessel and embedded technology, which can realize any positions measurement of a lake. This method has many advantages, such as mobile convenience, saving money and so on.

Modeling and Simulation Behavior Validation Methodology and Extension Model Validation for the Individual Soldier

DTIC Science & Technology

2015-03-01

domains. Major model functions include: • Ground combat: Light and heavy forces. • Air mobile forces. • Future forces. • Fixed-wing and rotary-wing...Constraints: • Study must be completed no later than 31 December 2014. • Entity behavior limited to select COMBATXXI Mobility , Unmanned Aerial System...and SQL backend , as well as any open application programming interface API. • Allows data transparency and data driven navigation through the model

Demonstration and Validation of a Waste-to-Energy Conversion System for Fixed DoD Installations

DTIC Science & Technology

2013-08-01

Corporation (IST Energy) was incorporated as a majority-owned subsidiary of IST to develop, market, manufacture and sell mobile , compact, and fully...provided the necessary infrastructure to support the Demonstration. The GEM WEC system was placed on a concrete pad provided by Edwards AFB near the...the Army Research Office [12, 13]. This program was part of a more inclusive program to develop a mobile waste-to-energy system to convert bulk

Renormalization group and Ward identities for infrared QED4

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

Mastropietro, Vieri

2007-10-15

A regularized version of Euclidean QED4 in the Feynman gauge is considered, with a fixed ultraviolet cutoff, photon mass of the size of the cutoff, and any value, including zero, of the electron mass. We will prove that the Schwinger functions are expressed by convergent series for small values of the charge and verify the Ward identities, up to corrections which are small for momentum scales far from the ultraviolet cutoff.

Stability of Nonlinear Swarms on Flat and Curved Surfaces

DTIC Science & Technology

numerical experiments have shown that the system either converges to a rotating circular limit cycle with a fixed center of mass, or the agents clump ...Swarming is a near-universal phenomenon in nature. Many mathematical models of swarms exist , both to model natural processes and to control robotic...agents. We study a swarm of agents with spring-like at-traction and nonlinear self-propulsion. Swarms of this type have been studied numerically, but

Existence and global attractivity of unique positive periodic solution for a model of hematopoiesis

NASA Astrophysics Data System (ADS)

Liu, Guirong; Yan, Jurang; Zhang, Fengqin

2007-10-01

In this paper, we consider the generalized model of hematopoiesis By using a fixed point theorem, some criteria are established for the existence of the unique positive [omega]-periodic solution of the above equation. In particular, we not only give the conclusion of convergence of xk to , where {xk} is a successive sequence, but also show that is a global attractor of all other positive solutions.

Fiber-FSO/wireless convergent systems based on dual-polarization and one optical sideband transmission schemes

NASA Astrophysics Data System (ADS)

Huang, Xu-Hong; Lu, Hai-Han; Li, Chung-Yi; Wang, Yun-Chieh; Chang, Jen-Chieh; Jheng, Yu-Bo; Tsai, Wen-Shing

2018-06-01

A bidirectional fiber-free-space optical (FSO)/wireless convergent system that uses dual-polarization and one optical sideband transmission schemes for hybrid vestigial sideband (VSB)–four-level pulse amplitude modulation (PAM4)/millimeter-wave signal transmission is proposed and demonstrated. Using a dual-polarization scheme, one optical sideband that is modulated by a 56 Gb s‑1 VSB–PAM4 signal (x-polarization) and another optical sideband that is modulated by a 10 Gbps data stream (y-polarization) are separated and polarized orthogonally. One optical sideband modulated by a 10 Gbps data stream (y-polarization) is delivered to efficaciously suppress the dispersion-induced limitation due to a span of 40 km single-mode fiber (SMF) and the distortion due to the beating among multiple sidebands. The proposed bidirectional fiber-FSO/wireless convergent system is a prominent one for providing broadband integrated services, such as the Internet, telecommunication, and 5G mobile networks.

Mobile phone-based interventions for smoking cessation.

PubMed

Whittaker, Robyn; McRobbie, Hayden; Bullen, Chris; Rodgers, Anthony; Gu, Yulong

2016-04-10

Access to mobile phones continues to increase exponentially globally, outstripping access to fixed telephone lines, fixed computers and the Internet. Mobile phones are an appropriate and effective option for the delivery of smoking cessation support in some contexts. This review updates the evidence on the effectiveness of mobile phone-based smoking cessation interventions. To determine whether mobile phone-based smoking cessation interventions increase smoking cessation in people who smoke and want to quit. For the most recent update, we searched the Cochrane Tobacco Addiction Group Specialised Register in April 2015. We also searched the UK Clinical Research Network Portfolio for current projects in the UK, and the ClinicalTrials.gov register for ongoing or recently completed studies. We searched through the reference lists of identified studies and attempted to contact the authors of ongoing studies. We applied no restrictions on language or publication date. We included randomised or quasi-randomised trials. Participants were smokers of any age who wanted to quit. Studies were those examining any type of mobile phone-based intervention for smoking cessation. This included any intervention aimed at mobile phone users, based around delivery via mobile phone, and using any functions or applications that can be used or sent via a mobile phone. Review authors extracted information on risk of bias and methodological details using a standardised form. We considered participants who dropped out of the trials or were lost to follow-up to be smoking. We calculated risk ratios (RR) and 95% confidence intervals (CI) for each included study. Meta-analysis of the included studies used the Mantel-Haenszel fixed-effect method. Where meta-analysis was not possible, we presented a narrative summary and descriptive statistics. This updated search identified 12 studies with six-month smoking cessation outcomes, including seven studies completed since the previous review. The interventions were predominantly text messaging-based, although several paired text messaging with in-person visits or initial assessments. Two studies gave pre-paid mobile phones to low-income human immunodeficiency virus (HIV)-positive populations - one solely for phone counselling, the other also included text messaging. One study used text messages to link to video messages. Control programmes varied widely. Studies were pooled according to outcomes - some providing measures of continuous abstinence or repeated measures of point prevalence; others only providing 7-day point prevalence abstinence. All 12 studies pooled using their most rigorous 26-week measures of abstinence provided an RR of 1.67 (95% CI 1.46 to 1.90; I(2) = 59%). Six studies verified quitting biochemically at six months (RR 1.83; 95% CI 1.54 to 2.19). The current evidence supports a beneficial impact of mobile phone-based smoking cessation interventions on six-month cessation outcomes. While all studies were good quality, the fact that those studies with biochemical verification of quitting status demonstrated an even higher chance of quitting further supports the positive findings. However, it should be noted that most included studies were of text message interventions in high-income countries with good tobacco control policies. Therefore, caution should be taken in generalising these results outside of this type of intervention and context.

Does core mobility of lumbar total disc arthroplasty influence sagittal and frontal intervertebral displacement? Radiologic comparison with fixed-core prosthesis

PubMed Central

Delécrin, Joël; Allain, Jérôme; Beaurain, Jacques; Steib, Jean-Paul; Chataigner, Hervé; Aubourg, Lucie; Huppert, Jean; Ameil, Marc; Nguyen, Jean-Michel

2009-01-01

Background An artificial disc prosthesis is thought to restore segmental motion in the lumbar spine. However, it is reported that disc prosthesis can increase the intervertebral translation (VT). The concept of the mobile-core prosthesis is to mimic the kinematic effects of the migration of the natural nucleus and therefore core mobility should minimize the VT. This study explored the hypothesis that core translation should influence VT and that a mobile core prosthesis may facilitate physiological motion. Methods Vertebral translation (measured with a new method presented here), core translation, range of motion (ROM), and distribution of flexion-extension were measured on flexion-extension, neutral standing, and lateral bending films in 89 patients (63 mobile-core [M]; 33 fixed-core [F]). Results At L4-5 levels the VT with M was lower than with F and similar to the VT of untreated levels. At L5-S1 levels the VT with M was lower than with F but was significantly different compared to untreated levels. At M levels a strong correlation was found between VT and core translation; the VT decreases as the core translation increases. At F levels the VT increases as the ROM increases. No significant difference was found between the ROM of untreated levels and levels implanted with either M or F. Regarding the mobility distribution with M and F we observed a deficit in extension at L5-S1 levels and a similar distribution at L4-5 levels compared to untreated levels. Conclusion The intervertebral mobility was different between M and F. The M at L4-5 levels succeeded to replicate mobility similar to L4-5 untreated levels. The M at L5-S1 succeeded in ROM, but failed regarding VT and mobility distribution. Nevertheless M minimized VT at L5-S1 levels. The F increased VT at both L4-5 and L5-S1. Clinical Relevance This study validates the concept that the core translation of an artificial lumbar disc prosthesis minimizes the VT. PMID:25802632

Why Do Medial Unicompartmental Knee Arthroplasties Fail Today?

PubMed

van der List, Jelle P; Zuiderbaan, Hendrik A; Pearle, Andrew D

2016-05-01

Failure rates are higher in medial unicompartmental knee arthroplasty (UKA) than total knee arthroplasty. To improve these failure rates, it is important to understand why medial UKA fail. Because individual studies lack power to show failure modes, a systematic review was performed to assess medial UKA failure modes. Furthermore, we compared cohort studies with registry-based studies, early with midterm and late failures and fixed-bearing with mobile-bearing implants. Databases of PubMed, EMBASE, and Cochrane and annual registries were searched for medial UKA failures. Studies were included when they reported >25 failures or when they reported early (<5 years), midterm (5-10 years), or late failures (>10 years). Thirty-seven cohort studies (4 level II studies and 33 level III studies) and 2 registry-based studies were included. A total of 3967 overall failures, 388 time-dependent failures, and 1305 implant design failures were identified. Aseptic loosening (36%) and osteoarthritis (OA) progression (20%) were the most common failure modes. Aseptic loosening (26%) was most common early failure mode, whereas OA progression was more commonly seen in midterm and late failures (38% and 40%, respectively). Polyethylene wear (12%) and instability (12%) were more common in fixed-bearing implants, whereas pain (14%) and bearing dislocation (11%) were more common in mobile-bearing implants. This level III systematic review identified aseptic loosening and OA progression as the major failure modes. Aseptic loosening was the main failure mode in early years and mobile-bearing implants, whereas OA progression caused most failures in late years and fixed-bearing implants. Copyright © 2016 Elsevier Inc. All rights reserved.

Single-molecule studies of oligomer extraction and uptake of dyes in poly(dimethylsiloxane) films.

PubMed

Lange, Jeffrey J; Collinson, Maryanne M; Culbertson, Christopher T; Higgins, Daniel A

2009-12-15

Single-molecule microscopic methods were used to probe the uptake, mobility, and entrapment of dye molecules in cured poly(dimethylsiloxane) (PDMS) films as a function of oligomer extraction. The results are relevant to the use of PDMS in microfluidic separations, pervaporation, solid-phase microextraction, and nanofiltration. PDMS films were prepared by spin-casting dilute solutions of Sylgard 184 onto glass coverslips, yielding approximately 1.4 microm thick films after curing. Residual oligomers were subsequently extracted from the films by "spin extraction". In this procedure, 200 microL aliquots of isopropyl alcohol were repeatedly dropped onto the film surface and spun off at 2000 rpm. Samples extracted 5, 10, 20, and 40 times were investigated. Dye molecules were loaded into these films by spin-casting nanomolar dye solutions onto the films. Both neutral perylene diimide (N,N'-bis(butoxypropyl)perylene-3,4,9,10-tetracarboxylic diimide) and cationic rhodamine 6G (R6G) dyes were employed. The films were imaged by confocal fluorescence microscopy. The images obtained depict nonzero populations of fixed and mobile molecules in all films. Cross-correlation methods were used to quantitatively determine the population of fixed molecules in a given region, while a Bayesian burst analysis was used to obtain the total population of molecules. The results show that the total amount of dye loaded increases with increased oligomer extraction, while the relative populations of fixed and mobile molecules decrease and increase, respectively. Bulk R6G data also show greater dye loading with increased oligomer extraction.

The Role of Face and Body Cues in Children's Judgments of Front, Back, and Side.

ERIC Educational Resources Information Center

Harris, Lauren; Strommen, Ellen

Forty boys and forty girls from kindergarten through fourth grade placed dolls with mobile heads in front of, behind and beside themselves, and in front of, behind and beside another doll to demonstrate development of spatial concepts. The heads and bodies of both dolls were either in convergent or divergent alignment or some combination.…

Affordance Access Matters: Preschool Children's Learning Progressions While Interacting with Touch-Screen Mathematics Apps

ERIC Educational Resources Information Center

Bullock, Emma P.; Shumway, Jessica F.; Watts, Christina M.; Moyer-Packenham, Patricia S.

2017-01-01

The purpose of this study was to contribute to the research on mathematics app use by very young children, and specifically mathematics apps for touch-screen mobile devices that contain virtual manipulatives. The study used a convergent parallel mixed methods design, in which quantitative and qualitative data were collected in parallel, analyzed…

Where Low and High Inference Data Converge: Validation of CLASS Assessment of Mathematics Instruction Using Mobile Eye Tracking with Expert and Novice Teachers

ERIC Educational Resources Information Center

Cortina, Kai S.; Miller, Kevin F.; McKenzie, Ryan; Epstein, Alanna

2015-01-01

Classroom observation research and research on teacher expertise are similar in their reliance on observational data with high-inference procedure to assess the quality of instruction. Expertise research usually uses low-inference measures like eye tracking to identify qualitative difference between expert and novice behaviors and cognition. In…

Continuous Monitoring of Mobility, Burial and Re exposure of Underwater Munitions in Energetic Near Shore Environments

DTIC Science & Technology

2017-01-01

parameters on Wasque Shoals ..................................................... 22 Figure 19. Rotary sonar imagery showing migrating mega- ripples and the...shown by the green and yellow lines reveals the convergence and divergence of the migrating mega- ripples ...26 Figure 24. Succesive rotary sonar images showing transient burial and reexposure of a surrogate UXO by migrating mega- ripples

[Mobility of physicians in Europe: health policies and health care provision].

PubMed

Jourdain, Alain; Pham, Tam

2017-03-06

Objective: To define the place of geographical mobility of physicians in medical demography policies in EU countries. Methods: Review of international migration assumptions in national projection models of numbers of physicians by broad categories of social protection systems in the EU. Results: Some countries fail to achieve medium-term projections of the number of physicians and those that do adopt the assumption of net migration, assume that they converge to zero. Migration is not considered to be a solution to the expected shortage of physicians, but rather a problem to be solved. Discussion: Three approaches to labour mobility are discussed: liberal, normative and ethical. The last approach appears to be the most popular by combining preservation of national interests with the World Health Organisation Global Code of Practice on the International Recruitment of Health Personnel.

SMART operational field test evaluation : customer survey report : final report

DOT National Transportation Integrated Search

1997-06-01

The Suburban Mobility Authority for Regional Transportation (SMART), which provides both paratransit and fixed-route service in the Detroit metropolitan area, has engaged in a program to update its paratransit operations--which it calls Community Tra...

Broadband wireless, integrated services, and their application to intelligent transportation systems

DOT National Transportation Integrated Search

2000-06-01

This paper introduces some of the newer broadband wireless communications alternatives and describes how they could be used to provide high-speed connections between fixed, transportable, and mobile facilities. We also describe the new integrated ser...

ROVER : prototype roving verification van : transportation project summary

DOT National Transportation Integrated Search

1997-06-01

The purpose of this project is to verify the safety and legality of commercial vehicles at both fixed and mobile roadside sites. improving the efficiency, safety. and effectiveness of commercial vehicle operations through the use of timely, accurate ...

Second order upwind Lagrangian particle method for Euler equations

DOE PAGES

Samulyak, Roman; Chen, Hsin -Chiang; Yu, Kwangmin

2016-06-01

A new second order upwind Lagrangian particle method for solving Euler equations for compressible inviscid fluid or gas flows is proposed. Similar to smoothed particle hydrodynamics (SPH), the method represents fluid cells with Lagrangian particles and is suitable for the simulation of complex free surface / multiphase flows. The main contributions of our method, which is different from SPH in all other aspects, are (a) significant improvement of approximation of differential operators based on a polynomial fit via weighted least squares approximation and the convergence of prescribed order, (b) an upwind second-order particle-based algorithm with limiter, providing accuracy and longmore » term stability, and (c) accurate resolution of states at free interfaces. In conclusion, numerical verification tests demonstrating the convergence order for fixed domain and free surface problems are presented.« less

Adaptive Discrete Hypergraph Matching.

PubMed

Yan, Junchi; Li, Changsheng; Li, Yin; Cao, Guitao

2018-02-01

This paper addresses the problem of hypergraph matching using higher-order affinity information. We propose a solver that iteratively updates the solution in the discrete domain by linear assignment approximation. The proposed method is guaranteed to converge to a stationary discrete solution and avoids the annealing procedure and ad-hoc post binarization step that are required in several previous methods. Specifically, we start with a simple iterative discrete gradient assignment solver. This solver can be trapped in an -circle sequence under moderate conditions, where is the order of the graph matching problem. We then devise an adaptive relaxation mechanism to jump out this degenerating case and show that the resulting new path will converge to a fixed solution in the discrete domain. The proposed method is tested on both synthetic and real-world benchmarks. The experimental results corroborate the efficacy of our method.

Second order upwind Lagrangian particle method for Euler equations

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

Samulyak, Roman; Chen, Hsin -Chiang; Yu, Kwangmin

A new second order upwind Lagrangian particle method for solving Euler equations for compressible inviscid fluid or gas flows is proposed. Similar to smoothed particle hydrodynamics (SPH), the method represents fluid cells with Lagrangian particles and is suitable for the simulation of complex free surface / multiphase flows. The main contributions of our method, which is different from SPH in all other aspects, are (a) significant improvement of approximation of differential operators based on a polynomial fit via weighted least squares approximation and the convergence of prescribed order, (b) an upwind second-order particle-based algorithm with limiter, providing accuracy and longmore » term stability, and (c) accurate resolution of states at free interfaces. In conclusion, numerical verification tests demonstrating the convergence order for fixed domain and free surface problems are presented.« less

Advanced statistical energy analysis

NASA Astrophysics Data System (ADS)

Heron, K. H.

1994-09-01

A high-frequency theory (advanced statistical energy analysis (ASEA)) is developed which takes account of the mechanism of tunnelling and uses a ray theory approach to track the power flowing around a plate or a beam network and then uses statistical energy analysis (SEA) to take care of any residual power. ASEA divides the energy of each sub-system into energy that is freely available for transfer to other sub-systems and energy that is fixed within the sub-systems that are physically separate and can be interpreted as a series of mathematical models, the first of which is identical to standard SEA and subsequent higher order models are convergent on an accurate prediction. Using a structural assembly of six rods as an example, ASEA is shown to converge onto the exact results while SEA is shown to overpredict by up to 60 dB.

Estimates of Environmental Exposure to Radiofrequency Electromagnetic Fields and Risk of Lymphoma Subtypes.

PubMed

Satta, G; Mascia, N; Serra, T; Salis, A; Saba, L; Sanna, S; Zucca, M G; Angelucci, E; Gabbas, A; Culurgioni, F; Pili, P; Mura, E; Cappai, M; Ennas, M G; Cocco, P

2018-05-01

We investigated the association between environmental exposure to radiofrequency electromagnetic fields (RF-EMF) and risk of lymphoma subtypes in a case-control study comprised of 322 patients and 444 individuals serving as controls in Sardinia, Italy in 1998-2004. Questionnaire information included the self-reported distance of the three longest held residential addresses from fixed radio-television transmitters and mobile phone base stations. We georeferenced the residential addresses of all study subjects and obtained the spatial coordinates of mobile phone base stations. For each address within a 500-meter radius from a mobile phone base station, we estimated the RF-EMF intensity using predictions from spatial models, and we performed RF-EMF measurements at the door in the subset of the longest held addresses within a 250-meter radius. We calculated risk of lymphoma and its major subtypes associated with the RF-EMF exposure metrics with unconditional logistic regression, adjusting by age, gender and years of education. In the analysis of self-reported data, risk associated with residence in proximity (within 50 meters) to fixed radio-television transmitters was likewise elevated for lymphoma overall [odds ratio = 2.7, 95% confidence interval = 1.5-4.6], and for the major lymphoma subtypes. With reference to mobile phone base stations, we did not observe an association with either the self-reported, or the geocoded distance from mobile phone base stations. RF-EMF measurements did not vary by case-control status. By comparing the self-reports to the geocoded data, we discovered that the cases tended to underestimate the distance from mobile phone base stations differentially from the controls ( P = 0.073). The interpretation of our findings is compromised by the limited study size, particularly in the analysis of the individual lymphoma subtypes, and the unavailability of the spatial coordinates of radio-television transmitters. Nonetheless, our results do not support the hypothesis of a link between environmental exposure to RF-EMF from mobile phone base stations and risk of lymphoma subtypes.

A Methylene Group on C-2 of 24,24-Difluoro-19-nor-1α,25-Dihydroxyvitamin D3 Markedly Increases Bone Calcium Mobilization in vivo

PubMed Central

Flores, Agnieszka; Massarelli, Ilaria; Thoden, James B.; Plum, Lori A.; DeLuca, Hector F.

2015-01-01

Four side chain fluorinated analogues of 1α,25-dihydroxy-19-norvitamin D have been prepared in convergent syntheses using the Wittig-Horner reaction as a key step. Structures and absolute configurations of analogues 3 and 5 were confirmed by X-ray crystallography. All analogues showed high potency in HL-60 cell differentiation and vitamin D-24-hydroxylase (24-OHase) transcription as compared to 1α,25-dihydroxyvitamin D3 (1). Most important is that all of the 20S-configured derivatives (4 and 6) had high bone mobilizing activity in vivo. However, in the 20R series, a 2-methylene group was required for high bone mobilizing activity. A change in positioning of the 20R molecule in the vitamin D receptor when the 2-methylene group is present may provide new insight into the molecular basis of bone calcium mobilization induced by vitamin D. PMID:26630444

Fixed forced detection for fast SPECT Monte-Carlo simulation

NASA Astrophysics Data System (ADS)

Cajgfinger, T.; Rit, S.; Létang, J. M.; Halty, A.; Sarrut, D.

2018-03-01

Monte-Carlo simulations of SPECT images are notoriously slow to converge due to the large ratio between the number of photons emitted and detected in the collimator. This work proposes a method to accelerate the simulations based on fixed forced detection (FFD) combined with an analytical response of the detector. FFD is based on a Monte-Carlo simulation but forces the detection of a photon in each detector pixel weighted by the probability of emission (or scattering) and transmission to this pixel. The method was evaluated with numerical phantoms and on patient images. We obtained differences with analog Monte Carlo lower than the statistical uncertainty. The overall computing time gain can reach up to five orders of magnitude. Source code and examples are available in the Gate V8.0 release.

Fixed forced detection for fast SPECT Monte-Carlo simulation.

PubMed

Cajgfinger, T; Rit, S; Létang, J M; Halty, A; Sarrut, D

2018-03-02

Monte-Carlo simulations of SPECT images are notoriously slow to converge due to the large ratio between the number of photons emitted and detected in the collimator. This work proposes a method to accelerate the simulations based on fixed forced detection (FFD) combined with an analytical response of the detector. FFD is based on a Monte-Carlo simulation but forces the detection of a photon in each detector pixel weighted by the probability of emission (or scattering) and transmission to this pixel. The method was evaluated with numerical phantoms and on patient images. We obtained differences with analog Monte Carlo lower than the statistical uncertainty. The overall computing time gain can reach up to five orders of magnitude. Source code and examples are available in the Gate V8.0 release.