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Steffen Helquist - One of the best experts on this subject based on the ideXlab platform.

  • randomized comparison of Deliverability and in hospital complications in implantation of bxsonic r express r and flexmaster r coronary stents
    Eurointervention, 2005
    Co-Authors: Leif Thuesen, P R Hansen, Knud Erik Pedersen, Jan Ravkilde, Henning Kelbæk, Per Thayssen, Klaus Rasmussen, Jens Flensted Lassen, Anders Galloe, Steffen Helquist
    Abstract:

    Aims: To compare Deliverability and in-hospital complications in implantation of BxSonic ® , Express ® , and Flexmaster ® coronary stents in a randomized multicenter trial in five Danish interventional centres. Methods and results: Patients with planned stenting of at least one stenotic lesion in a native coronary artery were included in the study. There were 494 (664) patients (treated lesions) in the BxSonic ® , 499 (657) in the Express ® and 500 (658) in the Flexmaster ® groups. The groups were well matched with regard to age, sex, diabetes, smoking, hypercholesterolemia, hypertension, indication for PCI and coronary artery lesion complexity. The study stents were implanted with or without predilatation according to ordinary clinical practice.Rates of successful stent implantation and in-hospital stent thrombosis, re-intervention, non-fatal myocardial infarction or death. The BxSonic ® , Express ® and Flexmaster ® stents were successfully implanted in 92,2%, 89,3% and 91,6% of all lesions (ns). There were no in-hospital deaths and the rates of in-hospital complications were similar in the three stent groups. Conclusion: We found similar Deliverability and in-hospital complication rates of the BxSonic ® , Express ® and Flexmaster ® stents.

  • randomized comparison of Deliverability and in hospital complications in implantation of bxsonic r express r and flexmaster r coronary stents
    Eurointervention, 2005
    Co-Authors: Leif Thuesen, P R Hansen, Knud Erik Pedersen, Jan Ravkilde, Henning Kelbæk, Per Thayssen, Klaus Rasmussen, Jens Flensted Lassen, Anders Galloe, Steffen Helquist
    Abstract:

    AIMS: To compare Deliverability and in-hospital complications in implantation of BxSonic(R), Express(R), and Flexmaster(R) coronary stents in a randomized multicenter trial in five Danish interventional centres. METHODS AND RESULTS: Patients with planned stenting of at least one stenotic lesion in a native coronary artery were included in the study. There were 494 (664) patients (treated lesions) in the BxSonic(R), 499 (657) in the Express(R) and 500 (658) in the Flexmaster(R) groups. The groups were well matched with regard to age, sex, diabetes, smoking, hypercholesterolemia, hypertension, indication for PCI and coronary artery lesion complexity. The study stents were implanted with or without predilatation according to ordinary -clinical practice.Rates of successful stent implantation and in-hospital stent thrombosis, re-intervention, non-fatal myocardial infarction or death. The BxSonic(R), Express(R) and Flexmaster(R) stents were successfully implanted in 92,2%, 89,3% and 91,6% of all lesions (ns). There were no in-hospital deaths and the rates of in-hospital complications were similar in the three stent groups. CONCLUSION: We found similar Deliverability and in-hospital complication rates of the BxSonic(R), Express(R) and Flexmaster(R) stents.

Yangyang He - One of the best experts on this subject based on the ideXlab platform.

  • characterizing data Deliverability of greedy routing in wireless sensor networks
    IEEE Transactions on Mobile Computing, 2018
    Co-Authors: Haiying Shen, Jason Hallstrom, Jiannan Zhai, Husnu Saner Narman, Lei Yu, Yangyang He
    Abstract:

    As a popular routing protocol in wireless sensor networks (WSNs), greedy routing has received great attention. The previous works characterize its data Deliverability in WSNs by the probability of all nodes successfully sending their data to the base station. Their analysis, however, neither provides the information of the quantitative relation between successful data delivery ratio and transmission power of sensor nodes nor considers the impact of the network congestion or link collision on the data Deliverability. To address these problems, in this paper, we characterize the data Deliverability of greedy routing by the ratio of successful data transmissions from sensors to the base station. We introduce $\eta$ -guaranteed delivery which means that the ratio of successful data deliveries is not less than $\eta$ , and study the relationship between the transmission power of sensors and the probability of achieving $\eta$ -guaranteed delivery. Furthermore, with considering the effect of network congestion, link collision, and holes (e.g., those caused by physical obstacles such as a lake), we provide a more precise and full characterization for the Deliverability of greedy routing. Extensive simulation and real-world experimental results show the correctness and tightness of the upper bound of the smallest transmission power for achieving $\eta$ -guaranteed delivery.

  • Characterizing Data Deliverability of Greedy Routing in Wireless Sensor Networks
    IEEE Transactions on Mobile Computing, 2018
    Co-Authors: Haiying Shen, Jason Hallstrom, Jiannan Zhai, Husnu Saner Narman, Lei Yu, Yangyang He
    Abstract:

    As a popular routing protocol in wireless sensor networks (WSNs), greedy routing has received great attention. The previous works characterize its data Deliverability in WSNs by the probability of all nodes successfully sending their data to the base station. Their analysis, however, neither provides the information of the quantitative relation between successful data delivery ratio and transmission power of sensor nodes nor considers the impact of the network congestion or link collision on the data Deliverability. To address these problems, in this paper, we characterize the data Deliverability of greedy routing by the ratio of successful data transmissions from sensors to the base station. We introduce n-guaranteed delivery which means that the ratio of successful data deliveries is not less than n, and study the relationship between the transmission power of sensors and the probability of achieving n-guaranteed delivery. Furthermore, with considering the effect of network congestion, link collision, and holes (e.g., those caused by physical obstacles such as a lake), we provide a more precise and full characterization for the Deliverability of greedy routing. Extensive simulation and real-world experimental results show the correctness and tightness of the upper bound of the smallest transmission power for achieving n-guaranteed delivery.

  • Characterizing data Deliverability of greedy routing in wireless sensor networks
    2015 12th Annual IEEE International Conference on Sensing Communication and Networking (SECON), 2015
    Co-Authors: Lei Yu, Yangyang He, Haiying Shen, Jason Hallstrom
    Abstract:

    As a popular routing protocol in wireless sensor networks (WSNs), greedy routing has received great attention. The previous works characterize its data Deliverability in WSNs by the probability of all nodes successfully sending their data to the base station. Their analysis, however, neither provides the information of the quantitative relation between successful data delivery ratio and transmission power of sensor nodes nor considers the impact of the network congestion or link collision on the data Deliverability. To address these problems, in this paper, we characterize the data Deliverability of greedy routing by the ratio of successful data transmissions from sensors to the base station. We introduce η-guaranteed delivery which means that the ratio of successful data deliveries is not less than η, and study the relationship between the transmission power of sensors and the probability of achieving η-guaranteed delivery. Furthermore, with considering the effect of network congestion and link collision, we provide a more precise and full characterization for the Deliverability of greedy routing. Extensive simulation and real-world experimental results show the correctness and tightness of the upper bound of the smallest transmission power for achieving η-guaranteed delivery.

Jinling Yi - One of the best experts on this subject based on the ideXlab platform.

  • su f p 64 the impact of plan complexity parameters on the plan quality and Deliverability of volumetric modulated arc therapy with canonical correlation analysis
    Medical Physics, 2016
    Co-Authors: Jinling Yi
    Abstract:

    Purpose: To evaluate the impact of complexity indices on the plan quality and Deliverability of volumetric modulated arc therapy (VMAT), and to determine the most significant parameters in the generation of an ideal VMAT plan. Methods: A multi-dimensional exploratory statistical method, canonical correlation analysis (CCA) was adopted to study the correlations between VMAT parameters of complexity, quality and Deliverability, as well as their contribution weights with 32 two-arc VMAT nasopharyngeal cancer (NPC) patients and 31 one-arc VMAT prostate cancer patients. Results: The MU per arc (MU/Arc) and MU per control point (MU/CP) of NPC were 337.8±25.2 and 3.7±0.3, respectively, which were significantly lower than those of prostate cancer patients (MU/Arc : 506.9±95.4, MU/CP : 5.6±1.1). The plan complexity indices indicated that two-arc VMAT plans were more complex than one-arc VMAT plans. Plan quality comparison confirmed that one-arc VMAT plans had a high quality than two-arc VMAT plans. CCA results implied that plan complexity parameters were highly correlated with plan quality with the first two canonical correlations of 0.96, 0.88 (both p<0.001) and significantly correlated with Deliverability with the first canonical correlation of 0.79 (p<0.001), plan quality and Deliverability was also correlated with the first canonical correlation of 0.71 (p=0.02). Complexity parameters of MU/CP, segment area (SA) per CP, percent of MU/CP less 3 and planning target volume (PTV) were weighted heavily in correlation with plan quality and deliveability . Similar results obtained from individual NPC and prostate CCA analysis. Conclusion: Relationship between complexity, quality, and Deliverability parameters were investigated with CCA. MU, SA related parameters and PTV volume were found to have strong effect on the plan quality and Deliverability. The presented correlation among different quantified parameters could be used to improve the plan quality and the efficiency of the radiotherapy process when creating a complex VMAT plan.

Yujun Li - One of the best experts on this subject based on the ideXlab platform.

  • Deliverability analysis of greedy routing in the spherical cap 3d sensor networks
    Science in China Series F: Information Sciences, 2013
    Co-Authors: Yaling Yang, Yujun Li
    Abstract:

    For 3D sensor networks to monitor the ocean, forest and aerosphere, etc., sensors can forward their data to the base station by greedy routing. It is critical to quantitatively greedy routing’s Deliverability for evaluating network’s functionality and performance. The probability that all sensors can successfully send their data to the base station by greedy routing is usually modeled as the probability of guaranteed delivery. For a typical spherical cap 3D sensor network deployment scenario where nodes follow a homogeneous Poisson point process, the relationship between the sensor transmission radius and the probability of guaranteed delivery is studied, and a tight analytical upper bound on the sensor transmission radius to ensure the designed Deliverability probability is derived in this paper. The correctness and tightness of the derived upper bound are verified by extensive simulations.

  • Many-to-one Deliverability of greedy routing in 2-D wireless sensor networks
    2011 Proceedings IEEE INFOCOM, 2011
    Co-Authors: Yaling Yang, Yujun Li
    Abstract:

    In this paper, we study Deliverability of greedy routing in wireless sensor networks, where nodes are distributed over a disk area according to a homogeneous Poisson point process. In our work, we model the level of Deliverability of a sensor network as the probability that all sensor nodes can successfully send their data to a base station, which is named probability of guaranteed delivery. We study the relationship between the critical transmission power of sensor nodes and the probability of guaranteed delivery, such that when all sensor nodes transmit with a higher power than the critical transmission power, the sensor network can reach the desired probability of guaranteed delivery. We identify two very tight analytical upper bounds on the critical transmission power for the idealistic u-disk model and the realistic log-normal shadowing model respectively. The correctness and tightness of these two upper bounds are verified by extensive simulations.

  • notice of retraction Deliverability of greedy routing in underwater sensor networks
    International Conference on Computer Engineering and Technology, 2010
    Co-Authors: Yujun Li, Yaling Yang
    Abstract:

    Underwater sensor networks comprise of a variable number of sensors that can be deployed in the ocean to sense certain phenomena. With the advance in acoustic communication and sensor techniques, many applications of underwater sensor networks are envisioned. Quantitative analysis of packet Deliverability from sensor nodes to the base station is critical for evaluating functionality and performance of an underwater sensor network. The level of Deliverability of an underwater sensor network is modeled as the probability that all sensor nodes can successfully send their data to the base station by greedy routing, named probability of guaranteed delivery in this paper. We study the relationship between the critical transmission radius of sensor nodes and the probability of guaranteed delivery. We identify a very tight analytical upper bound on the critical transmission radius for a typical underwater sensor network deployment scenario. The correctness and tightness of the upper bound are verified by extensive simulations.

Yonghong Chen - One of the best experts on this subject based on the ideXlab platform.

  • A nodal regulation reserve pricing model for deregulated power systems
    2017 North American Power Symposium (NAPS), 2017
    Co-Authors: Fengyu Wang, Kory W. Hedman, Yonghong Chen, Rui Bo, Tao Ding
    Abstract:

    To improve reserve Deliverability, independent system operators (ISOs) acquire reserve on a zonal basis to ensure the reserves are at least zonally distributed. Notwithstanding the ability for zonal approaches to improve the reserve location, such approaches are imprecise and do not guarantee reserve Deliverability on a nodal basis. In order to satisfy operational requirements, unreliable market solutions require additional operator manual adjustments; such uneconomic adjustments are typically expensive and they can distort market price signals. This paper proposes an approach to acquire regulation reserve on a nodal basis. Analysis on the RTS-96 shows that modeling post nodal regulation reserve deployment constraints improve reserve Deliverability, market efficiency, and price signals.

  • Incorporating Post Zonal Reserve Deployment Transmission Constraints Into Energy and Ancillary Service Co-Optimization
    IEEE Transactions on Power Systems, 2014
    Co-Authors: Yonghong Chen, Paul Gribik, Joe Gardner
    Abstract:

    This paper presents a new approach implemented in MISO day-ahead and real-time energy and ancillary service market clearing processes to address the reserve Deliverability issue. In this approach, MISO enhanced the co-optimization process to incorporate post zonal reserve deployment transmission constraints. Reserves are procured within the co-optimization to meet both market-wide reserve requirements and ensure their Deliverability on a zonal basis. As a result, zonal market clearing prices (MCPs) for reserves can properly reflect the effects of zonal reserve deployment on transmission constraints under consideration.

  • Market Implications of Short-term Reserve Deliverability Enhancement
    IEEE Transactions on Power Systems, 1
    Co-Authors: Fengyu Wang, Yonghong Chen
    Abstract:

    Midcontinent Independent System Operator (MISO) plans to introduce 30-minute short-term reserve (STR) to address 30 minutes system flexibility needs. Transmission bottlenecks in the power system may inhibit the Deliverability of STR. Insufficient deliverable reserve may require additional operator manual adjustments, which may be uneconomic and distort the market price signal. To improve reserve Deliverability, event-based zonal STR clearing model and nodal STR clearing model are proposed to distribute reserve across the grid. This paper compares reserve Deliverability and market clearing prices between the zonal STR model and the nodal STR model. A new design on penalty function is proposed in this paper to reflect the true value of security constraints for reserve deployment with the consideration of multiple events. Analysis of MISO test cases shows that the zonal approach is imprecise and may not guarantee the actual post-event flows within the physical limits. Nodal STR model can improve the reserve Deliverability, market efficiency, and price signal.