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Yury A. Andreev - One of the best experts on this subject based on the ideXlab platform.

  • optimizing high power ultra wideband combined antennas for Maximum Radiation within finite aperture area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined antenna array is developed to maximize the effective potential gain ( $G_{ep}$ ) within finite aperture area for the high-power ultra-wideband (UWB) Radiation. The idea is to make the antenna element as small as possible, so that more elements can be arranged within the prescribed aperture area to maximize $G_{ep}$ of the UWB system. On the other hand, the antenna element should match the pulse excitation. This means that in the frequency domain, the working band of the antenna element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB antenna to match the pulsed excitation, based on which the minimum size of the antenna element can be determined. With this method, a four-element combined antenna array is designed. Also, an impedance transformer and power divider are designed to feed the antenna array. Also, a big combined antenna is developed with the same aperture dimensions (30 cm $\times30$ cm) as the antenna array. Then, the performances of the antenna array and the big antenna are measured and compared. Compared with the big antenna, $G_{ep}$ of the antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve $G_{ep}$ of the UWB system within the prescribed aperture area. Finally, the antenna array is furthermore optimized by adjusting the distances between the elements, and $G_{ep}$ is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

  • Optimizing High-Power Ultra-Wideband Combined Antennas for Maximum Radiation Within Finite Aperture Area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined antenna array is developed to maximize the effective potential gain (Gep) within finite aperture area for the high-power ultra-wideband (UWB) Radiation. The idea is to make the antenna element as small as possible, so that more elements can be arranged within the prescribed aperture area to maximize Gep of the UWB system. On the other hand, the antenna element should match the pulse excitation. This means that in the frequency domain, the working band of the antenna element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB antenna to match the pulsed excitation, based on which the minimum size of the antenna element can be determined. With this method, a four-element combined antenna array is designed. Also, an impedance transformer and power divider are designed to feed the antenna array. Also, a big combined antenna is developed with the same aperture dimensions (30 cm × 30 cm) as the antenna array. Then, the performances of the antenna array and the big antenna are measured and compared. Compared with the big antenna, Gep of the antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve Gep of the UWB system within the prescribed aperture area. Finally, the antenna array is furthermore optimized by adjusting the distances between the elements, and Gep is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

Shao-fei Wang - One of the best experts on this subject based on the ideXlab platform.

  • optimizing high power ultra wideband combined antennas for Maximum Radiation within finite aperture area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined antenna array is developed to maximize the effective potential gain ( $G_{ep}$ ) within finite aperture area for the high-power ultra-wideband (UWB) Radiation. The idea is to make the antenna element as small as possible, so that more elements can be arranged within the prescribed aperture area to maximize $G_{ep}$ of the UWB system. On the other hand, the antenna element should match the pulse excitation. This means that in the frequency domain, the working band of the antenna element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB antenna to match the pulsed excitation, based on which the minimum size of the antenna element can be determined. With this method, a four-element combined antenna array is designed. Also, an impedance transformer and power divider are designed to feed the antenna array. Also, a big combined antenna is developed with the same aperture dimensions (30 cm $\times30$ cm) as the antenna array. Then, the performances of the antenna array and the big antenna are measured and compared. Compared with the big antenna, $G_{ep}$ of the antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve $G_{ep}$ of the UWB system within the prescribed aperture area. Finally, the antenna array is furthermore optimized by adjusting the distances between the elements, and $G_{ep}$ is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

  • Optimizing High-Power Ultra-Wideband Combined Antennas for Maximum Radiation Within Finite Aperture Area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined antenna array is developed to maximize the effective potential gain (Gep) within finite aperture area for the high-power ultra-wideband (UWB) Radiation. The idea is to make the antenna element as small as possible, so that more elements can be arranged within the prescribed aperture area to maximize Gep of the UWB system. On the other hand, the antenna element should match the pulse excitation. This means that in the frequency domain, the working band of the antenna element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB antenna to match the pulsed excitation, based on which the minimum size of the antenna element can be determined. With this method, a four-element combined antenna array is designed. Also, an impedance transformer and power divider are designed to feed the antenna array. Also, a big combined antenna is developed with the same aperture dimensions (30 cm × 30 cm) as the antenna array. Then, the performances of the antenna array and the big antenna are measured and compared. Compared with the big antenna, Gep of the antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve Gep of the UWB system within the prescribed aperture area. Finally, the antenna array is furthermore optimized by adjusting the distances between the elements, and Gep is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

Masayuki Zuguchi - One of the best experts on this subject based on the ideXlab platform.

  • total entrance skin dose an effective indicator of Maximum Radiation dose to the skin during percutaneous coronary intervention
    American Journal of Roentgenology, 2007
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. A number of cases of Radiation-associated patient skin injury during percutaneous coronary intervention (PCI) have been reported. To protect against this complication, Maximum skin dose to the patient should be monitored in real time. Unfortunately, in most cardiac intervention procedures, real-time monitoring of Maximum skin dose is not possible. Angiographic X-ray units, however, display the patient's total entrance skin dose in real time. We therefore investigated the relation between Maximum skin dose and total entrance skin dose to determine whether total entrance skin dose can be used to estimate Maximum skin dose during PCI.MATERIALS AND METHODS. The dose–area product was measured, and Maximum skin dose and total entrance skin dose were calculated with a skin-dose-mapping software program. The target vessels of 194 PCI procedures were divided into four groups according to the American Heart Association (AHA) segment system.RESULTS. The Maximum skin dose constituted 48%, 52%, 50%, and 52%...

  • indicators of the Maximum Radiation dose to the skin during percutaneous coronary intervention in different target vessels
    Catheterization and Cardiovascular Interventions, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    Objectives: To evaluate whether the Maximum Radiation dose to the patient's skin (MSD) can be estimated during percutaneous coronary intervention (PCI) procedures, we investigated the relationship between the MSD and fluoroscopic time, dose-area product (DAP), and body weight, separately analyzing the relationships for different target vessels. Background: Many cases of skin injury caused by excessive Radiation exposure during cardiac intervention procedures have been reported. However, real-time Maximum-dose monitoring of the skin is unavailable for many cardiac intervention procedures. Methods: We studied 197 consecutive PCI procedures that involved a single target vessel and were conducted. The DAP was measured, and the MSD was calculated by a skin-dose mapping software program (Caregraph). The target vessels of the PCI procedures were divided into four groups based on the AHA classification system: AHA 5–10, left anterior descending artery domain (LAD), AHA 11–15, left circumflex artery domain (LCx), AHA 1–3 = R 1–3, and AHA 4 = R 4. Results: The correlation coefficient (r) between the MSD and fluoroscopic time was higher for the right coronary artery (RCA) vessels (R 1–3, 0.852; R 4, 0.715) than for the left coronary artery (LCA) vessels (LAD, 0.527; LCx, 0.646), and the r value between the MSD and DAP was higher for the RCA vessels (R 1–3, 0.871; R 4, 0.898) than for the LCA vessels (LAD, 0.628; LCx, 0.694). Similarly, the correlation coefficient between the MSD and weight × fluoroscopic time (WFP) was higher for the RCA vessels (R 1–3, 0.874; R 4, 0.807) than for the LCA vessels (LAD, 0.551; LCx, 0.735). Conclusions: The DAP and WFP can be used to estimate the MSD during PCI in the RCA but not in the LCA, especially the LAD. © 2006 Wiley-Liss, Inc.

  • relationship between fluoroscopic time dose area product body weight and Maximum Radiation skin dose in cardiac interventional procedures
    American Journal of Roentgenology, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Kunio Shirato, Hiroki Otani, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. Real-time Maximum dose monitoring of the skin is unavailable on many of the X-ray machines that are used for cardiac intervention procedures. Therefore, some reports have recommended that physicians record the fluoroscopic time for patients undergoing fluoroscopically guided intervention procedures. However, the relationship between the fluoroscopic time and the Maximum Radiation skin dose is not clear. This article describes the correlation between the Maximum Radiation skin dose and fluoroscopic time for patients undergoing cardiac intervention procedures. In addition, we examined whether the correlations between Maximum Radiation skin dose and body weight, fluoroscopic time, and dose–area product (DAP) were useful for estimating the Maximum skin dose during cardiac intervention procedures.MATERIALS AND METHODS. Two hundred consecutive cardiac intervention procedures were studied: 172 percutaneous coronary interventions and 28 cardiac radiofrequency catheter ablation (RFCA) procedures. The pa...

Koichi Chida - One of the best experts on this subject based on the ideXlab platform.

  • total entrance skin dose an effective indicator of Maximum Radiation dose to the skin during percutaneous coronary intervention
    American Journal of Roentgenology, 2007
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. A number of cases of Radiation-associated patient skin injury during percutaneous coronary intervention (PCI) have been reported. To protect against this complication, Maximum skin dose to the patient should be monitored in real time. Unfortunately, in most cardiac intervention procedures, real-time monitoring of Maximum skin dose is not possible. Angiographic X-ray units, however, display the patient's total entrance skin dose in real time. We therefore investigated the relation between Maximum skin dose and total entrance skin dose to determine whether total entrance skin dose can be used to estimate Maximum skin dose during PCI.MATERIALS AND METHODS. The dose–area product was measured, and Maximum skin dose and total entrance skin dose were calculated with a skin-dose-mapping software program. The target vessels of 194 PCI procedures were divided into four groups according to the American Heart Association (AHA) segment system.RESULTS. The Maximum skin dose constituted 48%, 52%, 50%, and 52%...

  • indicators of the Maximum Radiation dose to the skin during percutaneous coronary intervention in different target vessels
    Catheterization and Cardiovascular Interventions, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    Objectives: To evaluate whether the Maximum Radiation dose to the patient's skin (MSD) can be estimated during percutaneous coronary intervention (PCI) procedures, we investigated the relationship between the MSD and fluoroscopic time, dose-area product (DAP), and body weight, separately analyzing the relationships for different target vessels. Background: Many cases of skin injury caused by excessive Radiation exposure during cardiac intervention procedures have been reported. However, real-time Maximum-dose monitoring of the skin is unavailable for many cardiac intervention procedures. Methods: We studied 197 consecutive PCI procedures that involved a single target vessel and were conducted. The DAP was measured, and the MSD was calculated by a skin-dose mapping software program (Caregraph). The target vessels of the PCI procedures were divided into four groups based on the AHA classification system: AHA 5–10, left anterior descending artery domain (LAD), AHA 11–15, left circumflex artery domain (LCx), AHA 1–3 = R 1–3, and AHA 4 = R 4. Results: The correlation coefficient (r) between the MSD and fluoroscopic time was higher for the right coronary artery (RCA) vessels (R 1–3, 0.852; R 4, 0.715) than for the left coronary artery (LCA) vessels (LAD, 0.527; LCx, 0.646), and the r value between the MSD and DAP was higher for the RCA vessels (R 1–3, 0.871; R 4, 0.898) than for the LCA vessels (LAD, 0.628; LCx, 0.694). Similarly, the correlation coefficient between the MSD and weight × fluoroscopic time (WFP) was higher for the RCA vessels (R 1–3, 0.874; R 4, 0.807) than for the LCA vessels (LAD, 0.551; LCx, 0.735). Conclusions: The DAP and WFP can be used to estimate the MSD during PCI in the RCA but not in the LCA, especially the LAD. © 2006 Wiley-Liss, Inc.

  • relationship between fluoroscopic time dose area product body weight and Maximum Radiation skin dose in cardiac interventional procedures
    American Journal of Roentgenology, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Kunio Shirato, Hiroki Otani, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. Real-time Maximum dose monitoring of the skin is unavailable on many of the X-ray machines that are used for cardiac intervention procedures. Therefore, some reports have recommended that physicians record the fluoroscopic time for patients undergoing fluoroscopically guided intervention procedures. However, the relationship between the fluoroscopic time and the Maximum Radiation skin dose is not clear. This article describes the correlation between the Maximum Radiation skin dose and fluoroscopic time for patients undergoing cardiac intervention procedures. In addition, we examined whether the correlations between Maximum Radiation skin dose and body weight, fluoroscopic time, and dose–area product (DAP) were useful for estimating the Maximum skin dose during cardiac intervention procedures.MATERIALS AND METHODS. Two hundred consecutive cardiac intervention procedures were studied: 172 percutaneous coronary interventions and 28 cardiac radiofrequency catheter ablation (RFCA) procedures. The pa...

Masahiro Kohzuki - One of the best experts on this subject based on the ideXlab platform.

  • total entrance skin dose an effective indicator of Maximum Radiation dose to the skin during percutaneous coronary intervention
    American Journal of Roentgenology, 2007
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. A number of cases of Radiation-associated patient skin injury during percutaneous coronary intervention (PCI) have been reported. To protect against this complication, Maximum skin dose to the patient should be monitored in real time. Unfortunately, in most cardiac intervention procedures, real-time monitoring of Maximum skin dose is not possible. Angiographic X-ray units, however, display the patient's total entrance skin dose in real time. We therefore investigated the relation between Maximum skin dose and total entrance skin dose to determine whether total entrance skin dose can be used to estimate Maximum skin dose during PCI.MATERIALS AND METHODS. The dose–area product was measured, and Maximum skin dose and total entrance skin dose were calculated with a skin-dose-mapping software program. The target vessels of 194 PCI procedures were divided into four groups according to the American Heart Association (AHA) segment system.RESULTS. The Maximum skin dose constituted 48%, 52%, 50%, and 52%...

  • indicators of the Maximum Radiation dose to the skin during percutaneous coronary intervention in different target vessels
    Catheterization and Cardiovascular Interventions, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Yutaka Kagaya, Yoshihiro Takai, Masayuki Zuguchi
    Abstract:

    Objectives: To evaluate whether the Maximum Radiation dose to the patient's skin (MSD) can be estimated during percutaneous coronary intervention (PCI) procedures, we investigated the relationship between the MSD and fluoroscopic time, dose-area product (DAP), and body weight, separately analyzing the relationships for different target vessels. Background: Many cases of skin injury caused by excessive Radiation exposure during cardiac intervention procedures have been reported. However, real-time Maximum-dose monitoring of the skin is unavailable for many cardiac intervention procedures. Methods: We studied 197 consecutive PCI procedures that involved a single target vessel and were conducted. The DAP was measured, and the MSD was calculated by a skin-dose mapping software program (Caregraph). The target vessels of the PCI procedures were divided into four groups based on the AHA classification system: AHA 5–10, left anterior descending artery domain (LAD), AHA 11–15, left circumflex artery domain (LCx), AHA 1–3 = R 1–3, and AHA 4 = R 4. Results: The correlation coefficient (r) between the MSD and fluoroscopic time was higher for the right coronary artery (RCA) vessels (R 1–3, 0.852; R 4, 0.715) than for the left coronary artery (LCA) vessels (LAD, 0.527; LCx, 0.646), and the r value between the MSD and DAP was higher for the RCA vessels (R 1–3, 0.871; R 4, 0.898) than for the LCA vessels (LAD, 0.628; LCx, 0.694). Similarly, the correlation coefficient between the MSD and weight × fluoroscopic time (WFP) was higher for the RCA vessels (R 1–3, 0.874; R 4, 0.807) than for the LCA vessels (LAD, 0.551; LCx, 0.735). Conclusions: The DAP and WFP can be used to estimate the MSD during PCI in the RCA but not in the LCA, especially the LAD. © 2006 Wiley-Liss, Inc.

  • relationship between fluoroscopic time dose area product body weight and Maximum Radiation skin dose in cardiac interventional procedures
    American Journal of Roentgenology, 2006
    Co-Authors: Koichi Chida, Haruo Saito, Masahiro Kohzuki, Shoki Takahashi, Shogo Yamada, Kunio Shirato, Hiroki Otani, Masayuki Zuguchi
    Abstract:

    OBJECTIVE. Real-time Maximum dose monitoring of the skin is unavailable on many of the X-ray machines that are used for cardiac intervention procedures. Therefore, some reports have recommended that physicians record the fluoroscopic time for patients undergoing fluoroscopically guided intervention procedures. However, the relationship between the fluoroscopic time and the Maximum Radiation skin dose is not clear. This article describes the correlation between the Maximum Radiation skin dose and fluoroscopic time for patients undergoing cardiac intervention procedures. In addition, we examined whether the correlations between Maximum Radiation skin dose and body weight, fluoroscopic time, and dose–area product (DAP) were useful for estimating the Maximum skin dose during cardiac intervention procedures.MATERIALS AND METHODS. Two hundred consecutive cardiac intervention procedures were studied: 172 percutaneous coronary interventions and 28 cardiac radiofrequency catheter ablation (RFCA) procedures. The pa...