The Experts below are selected from a list of 629073 Experts worldwide ranked by ideXlab platform
José Azaña - One of the best experts on this subject based on the ideXlab platform.
-
Photonic temporal integration of broadband intensity waveforms over long Operation Time windows
Optics Letters, 2011Co-Authors: Mohammad H. Asghari, Yongwoo Park, José AzañaAbstract:We propose and experimentally demonstrate a novel design for temporal integration of microwave and optical intensity waveforms with combined high processing speed and a long Operation Time window. It is based on concatenating in series a discrete-Time (low-speed) photonic integrator and a high-speed analog Time-limited intensity integrator. This scheme is demonstrated here using a cascaded fiber-based interferometers’ system (as a passive eight-point discrete-Time integrator) and an analog Time-limited intensity integrator. The latter is based on temporal intensity modulation of the input waveform with a rectangular-like incoherent energy spectrum followed by linear dispersion. Using this setup, we experimentally achieve accurate Time integration of intensity signals with ∼36 GHz bandwidths over an Operation Time window of ∼4 ns, corresponding to a processing Time-bandwidth product of >144.
-
new design for photonic temporal integration with combined high processing speed and long Operation Time window
Optics Express, 2011Co-Authors: Mohammad H. Asghari, Yongwoo Park, José AzañaAbstract:We propose and experimentally prove a novel design for implementing photonic temporal integrators simultaneously offering a high processing bandwidth and a long Operation Time window, namely a large Time-bandwidth product. The proposed scheme is based on concatenating in series a Time-limited ultrafast photonic temporal integrator, e.g. implemented using a fiber Bragg grating (FBG), with a discrete-Time (bandwidth limited) optical integrator, e.g. implemented using an optical resonant cavity. This design combines the advantages of these two previously demonstrated photonic integrator solutions, providing a processing speed as high as that of the Time-limited ultrafast integrator and an Operation Time window fixed by the discrete-Time integrator. Proof-of-concept experiments are reported using a uniform fiber Bragg grating (as the original Time-limited integrator) connected in series with a bulk-optics coherent interferometers’ system (as a passive 4-points discrete-Time photonic temporal integrator). Using this setup, we demonstrate accurate temporal integration of complex-field optical signals with Time-features as fast as ~6 ps, only limited by the processing bandwidth of the FBG integrator, over Time durations as long as ~200 ps, which represents a 4-fold improvement over the Operation Time window (~50 ps) of the original FBG integrator.
-
New concept for ultra-broadband photonic integrator with fundamentally unlimited Operation Time window
Conference on Lasers and Electro-Optics International Quantum Electronics Conference, 2009Co-Authors: Mohammad H. Asghari, Yongwoo Park, Yitang Dai, Jianping Yao, José AzañaAbstract:We propose and demonstrate a concept for temporal integration of optical waveforms with no fundamental limitation on the device's Operation Time window and frequency bandwidth using a pulse multiplier concatenated with a fiber Bragg grating. (200.4740) Optical processing; (320.7080) Ultrafast devices; (060.3735) Fiber Bragg gratings;
Ferdinand Köckerling - One of the best experts on this subject based on the ideXlab platform.
-
Experience and dissection device are more relevant than patient-related factors for Operation Time in laparoscopic sigmoid resection—a retrospective 8-year observational study
International Journal of Colorectal Disease, 2017Co-Authors: Dirk Weyhe, Verena Nicole Uslar, Navid Tabriz, Ina Burkowski, Ralf Heinzel, Andreas Müller, Annette Belling, Ferdinand KöckerlingAbstract:Purpose Surgical outcome is influenced by multiple patient-specific factors and operative expertise of the surgeon. Clinical relevance of medical technical innovations often remains unclear even though laparoscopic surgical procedures are characterized by continual advancement of various devices. Lately, in dissection and sealing technology, fast-cutting ultrasonic scissors are combined with simultaneous bipolar coagulation (bimodal dissection device (BDD)). We investigated how this new technology, operative expertise, and patient-specific factors (body mass index, age) influence Operation Time in laparoscopic-assisted sigmoid resection. Methods Between 2008 and 2016, 161 laparoscopic sigmoid resections (52% conventional dissection device (CDD); 48% BDD) performed in a single center were retrospectively evaluated. Biometric patient data, complication rates, and surgery duration, reflecting the learning curve, were analyzed. Operations were performed by experienced surgeons ( n = 3) and trainees ( n = 4). Results Minor postoperative complications (e.g., impaired wound healing, non-revisional secondary bleeding) occurred in 11 cases (6.8%). Major complications (e.g., bleeding requiring revision, anastomotic leakage) were observed in 3.7%. No heat-related coagulation damage was observed. BDD reduced Operation Time for both experienced (CDD 150 min, BDD 125 min; p
Mohammad H. Asghari - One of the best experts on this subject based on the ideXlab platform.
-
Photonic temporal integration of broadband intensity waveforms over long Operation Time windows
Optics Letters, 2011Co-Authors: Mohammad H. Asghari, Yongwoo Park, José AzañaAbstract:We propose and experimentally demonstrate a novel design for temporal integration of microwave and optical intensity waveforms with combined high processing speed and a long Operation Time window. It is based on concatenating in series a discrete-Time (low-speed) photonic integrator and a high-speed analog Time-limited intensity integrator. This scheme is demonstrated here using a cascaded fiber-based interferometers’ system (as a passive eight-point discrete-Time integrator) and an analog Time-limited intensity integrator. The latter is based on temporal intensity modulation of the input waveform with a rectangular-like incoherent energy spectrum followed by linear dispersion. Using this setup, we experimentally achieve accurate Time integration of intensity signals with ∼36 GHz bandwidths over an Operation Time window of ∼4 ns, corresponding to a processing Time-bandwidth product of >144.
-
new design for photonic temporal integration with combined high processing speed and long Operation Time window
Optics Express, 2011Co-Authors: Mohammad H. Asghari, Yongwoo Park, José AzañaAbstract:We propose and experimentally prove a novel design for implementing photonic temporal integrators simultaneously offering a high processing bandwidth and a long Operation Time window, namely a large Time-bandwidth product. The proposed scheme is based on concatenating in series a Time-limited ultrafast photonic temporal integrator, e.g. implemented using a fiber Bragg grating (FBG), with a discrete-Time (bandwidth limited) optical integrator, e.g. implemented using an optical resonant cavity. This design combines the advantages of these two previously demonstrated photonic integrator solutions, providing a processing speed as high as that of the Time-limited ultrafast integrator and an Operation Time window fixed by the discrete-Time integrator. Proof-of-concept experiments are reported using a uniform fiber Bragg grating (as the original Time-limited integrator) connected in series with a bulk-optics coherent interferometers’ system (as a passive 4-points discrete-Time photonic temporal integrator). Using this setup, we demonstrate accurate temporal integration of complex-field optical signals with Time-features as fast as ~6 ps, only limited by the processing bandwidth of the FBG integrator, over Time durations as long as ~200 ps, which represents a 4-fold improvement over the Operation Time window (~50 ps) of the original FBG integrator.
-
New concept for ultra-broadband photonic integrator with fundamentally unlimited Operation Time window
Conference on Lasers and Electro-Optics International Quantum Electronics Conference, 2009Co-Authors: Mohammad H. Asghari, Yongwoo Park, Yitang Dai, Jianping Yao, José AzañaAbstract:We propose and demonstrate a concept for temporal integration of optical waveforms with no fundamental limitation on the device's Operation Time window and frequency bandwidth using a pulse multiplier concatenated with a fiber Bragg grating. (200.4740) Optical processing; (320.7080) Ultrafast devices; (060.3735) Fiber Bragg gratings;
Brian M Blake - One of the best experts on this subject based on the ideXlab platform.
-
an Operation Time simulation framework for uav swarm configuration and mission planning
International Conference on Conceptual Structures, 2013Co-Authors: Brian M Blake, Gregory R MadeyAbstract:In recent years, Unmanned Aerial Vehicles (UAV), have been increasingly utilized by both military and civilian organizations because they are less expensive, provide greater flexibilities and remove the need for on-board pilot support. Largely due to their utility and increased capabilities, in the near future, swarms of UAVs will replace single UAV use. Efficient control of swarms opens a set of new challenges, such as automatic UAV coordination, efficient swarm monitoring and dynamic mission planning. In this paper, we investigate the problem of dynamic mission planning for a UAV swarm. A centralized-distributed hybrid control framework is proposed for mission assignment and scheduling. The Dynamic Data Driven Application System (DDDAS) principles are applied to the framework so that it can adapt to the changing nature of the environment and the missions. A prototype simulation program is implemented as a proof-ofconcept of the framework. Experimentation with the framework suggests the effectiveness of swarm control for several mission planning mechanisms.
Daizo Saito - One of the best experts on this subject based on the ideXlab platform.
-
endoscopic submucosal dissection for early gastric cancer technical feasibility Operation Time and complications from a large consecutive series
Digestive Endoscopy, 2005Co-Authors: Takuji Gotoda, Hisanao Hamanaka, Takako Eguchi, Yutaka Saito, Takahisa Matsuda, Pradeep Bhandari, Fabian Emura, Daizo SaitoAbstract:Background: Endoscopic mucosal resection (EMR) is a recognized treatment for early gastric cancer (EGC). One-piece resection is considered to be a gold standard of EMR, as it provides accurate histological assessment and reduces the risk of local recurrence. Endoscopic submucosal dissection (ESD) is a new technique developed to obtain one-piece resection even for large and ulcerative lesions. The present study aims to identify the technical feasibility, Operation Time and complications from a large consecutive series. Methods: We reviewed all patients with EGC who underwent ESD using the IT knife at National Cancer Center Hospital in the period between January 2000 and December 2003. Results: During the study period of 4 years we identified a total of 1033 EGC lesions in 945 consecutive patients who underwent ESD using the IT knife. We found a one-piece resection rate (OPRR) of 98% (1008/1033). Our OPRR with tumor-free margins was 93% (957/1033). On subgroup analysis it was found to be 86% (271/314) among large lesions (≥ 21 mm) and 89% (216/243) among ulcerative lesions. The overall non-evaluable resection rate was 1.8% (19/1033). The median Operation Time was 60 min (range; 10–540 min). Evidence of immediate bleeding was found in 7%. Delayed bleeding after ESD was seen in 6% and perforation in 4% of the cases. All cases with complications except one were successfully treated by endoscopic treatment. Conclusion: The present study shows the technical feasibility of ESD, which provides one-piece resections even in large and ulcerative EGC.
