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oe1(光电查) - 科学论文

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?? 中文(中国)
  • [IEEE 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - Krakow, Poland (2018.10.16-2018.10.18)] 2018 IEEE International Conference on Imaging Systems and Techniques (IST) - A novel method to explore intrarenal arterial tree using micro-CT

    摘要: The minimally invasive approach for renal surgeries, among others, requires preoperative determination of intrarenal arteries. Their proper identification based on standard preoperative CT images is still not a fully solved problem. Therefore, we decided to resolve this issue by providing a tree topology model using post-mortem kidneys. The number of vessels that compose intrarenal tree is so large, that it cannot by analyzed manually without the aid of image processing techniques. So that, the vessels has to be first depicted using an imaging technique that enables to provide superior resolution in comparison to standard CT scan. In this paper, we present a research on various injection materials enabling to fill the vascular beds in order to scan them using micro-CT and further reconstruct as a 3D model. The evaluated materials were chosen so that they are widely available and affordable. We compare them in terms of their ability to absorb ionizing radiation and penetrate vascular beds (density, viscosity), homogeneity, solidification rate, resistance to solvents and durability. We also present the technique of injecting kidney arteries with the use of the selected material - two-part epoxy adhesive with 10% iodine. In contrast to standard corrosive endocast preparation, in our case there is no need to remove soft parenchymal tissue which takes about two weeks using corrosive materials such as strong acids and bases. The proposed filling material enables to enhance vascular tree to such extend that micro-CT scans of the whole kidneys can be performed. This enables instantaneous substance injection and imaging without permanently destroying the soft tissue material. This approach can be used in various scenarios in which a filling material with the ability to increase radiation absorption is required and there is a need to maintain the integrity of the structure. To the best of our knowledge, this is the first such attempt. The obtained vascular trees by the means of micro-CT confirm the validity of the presented approach.

    关键词: cast,micro-CT,3D vascular tree,minimally invasive surgery,contrast agents,ability to absorb ionizing radiation,kidney surgery,injection materials,kidney

    更新于2025-09-23 15:23:52

  • Avalia??o do conhecimento de médicos n?o radiologistas sobre aspectos relacionados à radia??o ionizante em exames de imagem

    摘要: Objective: To assess the non-radiologist physicians’ knowledge on the use of ionizing radiation in imaging. Materials and Methods: Cross-sectional study utilizing an anonymous questionnaire responded by physicians in clinical and surgical specialties, divided into two parts as follows: one including questions about the physicians’ characteristics, frequency of imaging studies requests and participation in professional updating events, and another part including multiple choice questions approaching general knowledge about radiation, optimization principles and radioprotection. Results: From a total of 309 questionnaires, 120 (38.8%) were responded, 50% by physicians in surgical specialties and 50% in clinical specialties; respectively 45% and 2.5% of physicians responded that magnetic resonance imaging and ultrasonography use ionizing radiation. Overall, the average grade was higher for surgical specialists with no significant difference, except for the question about exposure in pregnant women (p = 0.047). Physicians who are professionally updated, particularly those attending clinical meetings (p = 0.050) and participating in teaching activities (p = 0.047), showed statistically superior knowledge about ionizing radiation as compared with others. Conclusion: The non-radiologist physicians’ knowledge is heterogeneous and in some points needs to be improved. Multidisciplinary clinical meetings and teaching activities are important ways to disseminate information on the subject.

    关键词: Questionnaire.,Knowledge,Ionizing radiation,Imaging diagnosis,Physicians,Radiation protection

    更新于2025-09-23 15:22:29

  • Study of the effect of irradiation with Fe<sup>7+</sup> ions on the structural properties of thin TiO<sub>2</sub> foils

    摘要: Thin foils based on the TiO2 phase of brookite, 620 nm thick, were obtained by magnetron sputtering. The samples were irradiated at the DC-60 heavy ion accelerator of the Astana branch of the Institute of Nuclear Physics with Fe7+ ions with an energy of 85 MeV with a fluence of 1×1011 to 1×1014 ions/cm2. The dependences of the change in the concentration of defects in the structure of thin films on the radiation dose are established. It has been established that an increase in the irradiation fluence of up to 1014 ions/cm2, characteristic of the formation of defect overlap regions, leads to a sharp decrease in the degree of crystallinity and an increase in the lattice parameters. That is caused by the formation of a large number of disorder regions and displaced atoms in the structure, which migrate along the crystal lattice to additional distortions and voltages, with the subsequent formation of hillocks.

    关键词: ionizing radiation,thin foils,crystal structure defects,magnetron sputtering

    更新于2025-09-23 15:22:29

  • Heavily Irradiated 65-nm Readout Chip With Asynchronous Channels for Future Pixel Detectors

    摘要: This paper discusses the main results relevant to the characterization of an analog front-end processor designed in view of experiments with unprecedented particle rates and radiation levels at the high-luminosity Large Hadron Collider (HL-LHC). The front-end channel presented in this paper is part of the CHIPIX65-FE0 prototype, a readout application-speci?ed integrated circuit designed in a 65-nm CMOS technology in the frame of the CERN RD53 collaboration. The prototype integrates a 64 × 64 pixel matrix, divided into two 32 × 64 submatrices, featuring squared pixels with 50-μm pitch, embodying two analog front-end architectures based on synchronous and asynchronous hit discriminators. This paper is focused on the characterization of the array with asynchronous channels, before and after exposure to ionizing doses up to 630 Mrad(SiO2) of X-rays. The analog chain takes a per-channel area close to 1000 μm2, with a power dissipation of around 5 μW. The mean value of the equivalent noise charge, not signi?cantly affected by radiation, is close to 100 electrons with no sensor connected to the front end. The threshold dispersion before irradiation is 55 electrons, for a tuned threshold of 600 electrons, with a moderate increase after irradiation. In-pixel analog-to-digital conversion, based on the time-over-threshold technique, is not appreciably in?uenced by the radiation as well. The assessed performance guarantees sub-1000 electrons stable threshold operations, which is a mandatory feature for highly ef?cient readout chips at the HL-LHC.

    关键词: pixel readout,Analog front ends,electronic noise,CMOS processes,ionizing radiation effects

    更新于2025-09-23 15:21:01

  • [IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Generating and Steering of Quasi-nondiffraction Beam by Substrate Integrated Waveguide Slot Array Antenna

    摘要: This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (ψs) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimental I-V characteristics from irradiated devices. The modeling approach is suitable for simulating TID and aging effects in advanced MOS devices and ICs, and is compatible with modern MOSFET compact modeling techniques. A circuit-level demonstration is given for TID and aging effects in SRAM cells.

    关键词: MOSFET,SOI,semiconductor devices,compact modeling,ionizing radiation,Aging effects

    更新于2025-09-23 15:19:57

  • Ultra-High-Speed 2:1 Digital Selector and Plasmonic Modulator IM/DD Transmitter Operating at 222 GBaud for Intra-Datacenter Applications

    摘要: This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (ψs) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimental I-V characteristics from irradiated devices. The modeling approach is suitable for simulating TID and aging effects in advanced MOS devices and ICs, and is compatible with modern MOSFET compact modeling techniques. A circuit-level demonstration is given for TID and aging effects in SRAM cells.

    关键词: compact modeling,SOI,ionizing radiation,semiconductor devices,MOSFET,Aging effects

    更新于2025-09-23 15:19:57

  • [IEEE 2020 10th Annual Computing and Communication Workshop and Conference (CCWC) - Las Vegas, NV, USA (2020.1.6-2020.1.8)] 2020 10th Annual Computing and Communication Workshop and Conference (CCWC) - DFB Laser Chip Defect Detection Based on Successive Subspace Learning

    摘要: This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (ψs) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimental I-V characteristics from irradiated devices. The modeling approach is suitable for simulating TID and aging effects in advanced MOS devices and ICs, and is compatible with modern MOSFET compact modeling techniques. A circuit-level demonstration is given for TID and aging effects in SRAM cells.

    关键词: MOSFET,SOI,semiconductor devices,compact modeling,ionizing radiation,Aging effects

    更新于2025-09-23 15:19:57

  • Photodetectors based on solution-processable semiconductors: Recent advances and perspectives

    摘要: The detection of light, one of the most important technologies, has widespread applications in industry and our daily life, e.g., environmental monitoring, communications, surveillance, image sensors, and advanced diagnosis. Along with the remarkable progress in the field of organics, those based on quantum dots, and recently emerged perovskite optoelectronics, photodetectors based on these solution-processable semiconductors have shown unprecedented success. In this review, we present the basic operation mechanism and the characterization of the performance metrics based on these novel materials systems. Then, we focus on the current research status and recent advances with the following five aspects: (i) spectral tunability, (ii) cavity enhanced photodetectors, (iii) photomultiplication type photodetectors, (iv) sensitized phototransistors, and (v) ionizing radiation detection. At the end, we discuss the key challenges facing these novel photodetectors toward manufacture and viable applications. We also point out the opportunities, which are promising to explore and may require more research activities.

    关键词: sensitized phototransistors,photodetectors,cavity enhanced photodetectors,solution-processable semiconductors,photomultiplication type photodetectors,spectral tunability,ionizing radiation detection

    更新于2025-09-23 15:19:57

  • Light-Emitting Diodes (LEDS)

    摘要: Since the original ICNIRP Statement was published in 2000, there have been significant improvements in the efficiency and radiance (i.e., optical radiation emission) of LEDs. The most important improvement is the development of ‘white’ LEDs that can be used as general lighting sources, which are more efficient than traditional lighting sources. LEDs emitting in the ultraviolet wavelength region have also become available and have made their way into consumer products. All these changes have led to a rise in concern for the safety of the optical radiation emissions from LEDs. Several in vitro and animal studies have been conducted, which indicate that blue and white LEDs can potentially cause retinal cell damage under high irradiance and lengthy exposure conditions. However, these studies cannot be directly extrapolated to normal exposure conditions for humans, and equivalent effects can also be caused by the optical radiation from other light sources under extreme exposure conditions. Acute damage to the human retina from typical exposure to blue or white LEDs has not been demonstrated. Concern for potential long-term effects, e.g. age-related macular degeneration (AMD), remains based on epidemiological studies indicating a link between high levels of exposure to sunlight and AMD. When evaluating the optical radiation safety of LEDs, it has now been established that published safety standards for lamps, not lasers, should be applied. Thus far, the only clear, acute adverse health effects from LEDs are those due to temporal light modulation (including flicker). Glare can also create visual disturbances when LED light fixtures are not properly designed. Further research is needed on potential health effects from short- and long-term exposure to new and emerging lighting technologies.

    关键词: safety standards,radiation, non-ionizing,International Commission on Non Ionizing Radiation Protection,health effects

    更新于2025-09-19 17:13:59

  • [IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Towards a Suburban Quantum Network Link

    摘要: This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (ψs) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimental I-V characteristics from irradiated devices. The modeling approach is suitable for simulating TID and aging effects in advanced MOS devices and ICs, and is compatible with modern MOSFET compact modeling techniques. A circuit-level demonstration is given for TID and aging effects in SRAM cells.

    关键词: compact modeling,SOI,ionizing radiation,semiconductor devices,MOSFET,Aging effects

    更新于2025-09-19 17:13:59