The Experts below are selected from a list of 285147 Experts worldwide ranked by ideXlab platform

Chunting Chris Mi - One of the best experts on this subject based on the ideXlab platform.

  • loosely coupled transformer coil design to minimize emf Radiation in concerned areas
    IEEE Transactions on Vehicular Technology, 2016
    Co-Authors: Wei Zhang, Jeff C White, Rajesh Kumar Malhan, Chunting Chris Mi
    Abstract:

    Wireless power transfer (WPT) technology as a convenient and reliable charging method, its electromagnetic field (EMF) Radiation, and its compliance with human electromagnetic exposure limits have recently been studied. Different from the current research, which validates the EMF Radiation level of a predesigned WPT system, this paper presents the loosely coupled transformer design method to minimize the EMF in the concerned area. The energy storage in the primary and secondary coils is studied for all popular compensation topologies in recently reported research. The coil of the loosely coupled transformer is designed with the S-S compensation topology as an example. The EMF Radiation level is optimized to below the International Commission on Non-Ionizing Radiation Protection guideline in the concerned area. A 3.3-kW WPT system for electric vehicle wireless charging with an LCC-LCC compensation topology is designed with detailed process and experiment results, verifying that the EMF Radiation is controlled as designed. The numerical analysis of human exposure is performed with the finite-element method, and the results show compliance as expected.

  • loosely coupled transformer structure and interoperability study for ev wireless charging systems
    IEEE Transactions on Power Electronics, 2015
    Co-Authors: Wei Zhang, Jeff C White, Arpith Mathew Abraham, Chunting Chris Mi
    Abstract:

    As the wireless power transfer (WPT) technology has been proved to be a convenient and reliable charging method to plug-in hybrid electric vehicles and electric vehicles, the loosely coupled transformer structure and size are the primary and fundamental concern to design an efficient WPT system. In this paper, a double D (DD) coil and a unipolar coil are selected to conduct the study. We focus on the coil structure design to achieve the maximum coupling coefficient as well as efficiency with two situations: 1) with no misalignment, and 2) with a 75-mm door-to-door and 100-mm front-to-back misalignment at which the maximum operating capability can still be achieved. A coil size optimization process is proposed for both the DD coil and the unipolar coil configurations. The relationship between the size of the secondary (receiving) coil, which determines the weight of the pad on the vehicle, and achievable maximum efficiency is studied for both coil topologies. The interoperability between the two coil topologies is studied. The proposed transformer structures with aluminum shielding meet human exposure regulations of the International Commission on Non-Ionizing Radiation Protection guidelines as a foundation. Finally, experiments validated the analyses.

Wei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • loosely coupled transformer coil design to minimize emf Radiation in concerned areas
    IEEE Transactions on Vehicular Technology, 2016
    Co-Authors: Wei Zhang, Jeff C White, Rajesh Kumar Malhan, Chunting Chris Mi
    Abstract:

    Wireless power transfer (WPT) technology as a convenient and reliable charging method, its electromagnetic field (EMF) Radiation, and its compliance with human electromagnetic exposure limits have recently been studied. Different from the current research, which validates the EMF Radiation level of a predesigned WPT system, this paper presents the loosely coupled transformer design method to minimize the EMF in the concerned area. The energy storage in the primary and secondary coils is studied for all popular compensation topologies in recently reported research. The coil of the loosely coupled transformer is designed with the S-S compensation topology as an example. The EMF Radiation level is optimized to below the International Commission on Non-Ionizing Radiation Protection guideline in the concerned area. A 3.3-kW WPT system for electric vehicle wireless charging with an LCC-LCC compensation topology is designed with detailed process and experiment results, verifying that the EMF Radiation is controlled as designed. The numerical analysis of human exposure is performed with the finite-element method, and the results show compliance as expected.

  • loosely coupled transformer structure and interoperability study for ev wireless charging systems
    IEEE Transactions on Power Electronics, 2015
    Co-Authors: Wei Zhang, Jeff C White, Arpith Mathew Abraham, Chunting Chris Mi
    Abstract:

    As the wireless power transfer (WPT) technology has been proved to be a convenient and reliable charging method to plug-in hybrid electric vehicles and electric vehicles, the loosely coupled transformer structure and size are the primary and fundamental concern to design an efficient WPT system. In this paper, a double D (DD) coil and a unipolar coil are selected to conduct the study. We focus on the coil structure design to achieve the maximum coupling coefficient as well as efficiency with two situations: 1) with no misalignment, and 2) with a 75-mm door-to-door and 100-mm front-to-back misalignment at which the maximum operating capability can still be achieved. A coil size optimization process is proposed for both the DD coil and the unipolar coil configurations. The relationship between the size of the secondary (receiving) coil, which determines the weight of the pad on the vehicle, and achievable maximum efficiency is studied for both coil topologies. The interoperability between the two coil topologies is studied. The proposed transformer structures with aluminum shielding meet human exposure regulations of the International Commission on Non-Ionizing Radiation Protection guidelines as a foundation. Finally, experiments validated the analyses.

S M J Mortazavi - One of the best experts on this subject based on the ideXlab platform.

  • direct and indirect effects of exposure to 900 mhz gsm radiofrequency electromagnetic fields on cho cell line evidence of bystander effect by non ionizing Radiation
    Environmental Research, 2019
    Co-Authors: Najmeh Jooyan, Bahram Goliaei, Bahareh Bigdeli, Reza Farajidana, Ali Zamani, Milad Entezami, S M J Mortazavi
    Abstract:

    Abstract Introduction The rapid rise in global concerns about the adverse health effects of exposure to radiofrequency Radiation (RFR) generated by common devices such as mobile phones has prompted scientists to further investigate the biological effects of these environmental exposures. Non-targeted effects (NTEs) are responses which do not need a direct exposure to be expressed and are particularly significant at low energy Radiations. Although NTEs of ionizing Radiation are well documented, there are scarcely any studies on non-targeted responses such as bystander effect (BE) after exposure to Non-Ionizing Radiation. The main goal of this research is to study possible RFR-induced BE. Material and methods Chinese hamster ovary cells were exposed to 900 MHz GSM RFR at an average specific absorption rate (SAR) of 2 W/kg for 4, 12 and 24 hours (h). To generate a uniformly distributed electromagnetic field and avoid extraneous RF exposures a cavity was desined and used. Cell membrane permeability, cell redox activity, metabolic and mitotic cell death and DNA damages were analyzed. Then the most effective exposure durations and statistically significant altered parameters were chosen to assess the induction of BE through medium transfer procedure. Furthermore, intra and extra cellular reactive oxygen species (ROS) levels were measured to assess the molecular mechanism of BE induced by Non-Ionizing Radiation. Results No statistically significant alteration was found in cell membrane permeability, cell redox activity, metabolic cell activity and micronuclei (MN) frequency in the cells directly exposed to RFR for 4, 12, or 24 h. However, RFR exposure for 24 h caused a statistically significant decrease in clonogenic ability as well as a statistically significant increase in olive moment in both directly exposed and bystander cells which received media from RFR-exposed cells (conditioned culture medium; CCM). Exposure to RFR also statistically significant elevated both intra and extra cellular levels of ROS. Conclusion Our observation clearly indicated the induction of BE in cells treated with CCM. To our knowledge, this is the first report that a Non-Ionizing Radiation (900 MHz GSM RFR) can induce bystander effect. As reported for ionizing Radiation, our results proposed that ROS can be a potential molecule in indirect effect of RFR. On the other hand, we found the importance of ROS in direct effect of RFR but in different ways.

Jeff C White - One of the best experts on this subject based on the ideXlab platform.

  • loosely coupled transformer coil design to minimize emf Radiation in concerned areas
    IEEE Transactions on Vehicular Technology, 2016
    Co-Authors: Wei Zhang, Jeff C White, Rajesh Kumar Malhan, Chunting Chris Mi
    Abstract:

    Wireless power transfer (WPT) technology as a convenient and reliable charging method, its electromagnetic field (EMF) Radiation, and its compliance with human electromagnetic exposure limits have recently been studied. Different from the current research, which validates the EMF Radiation level of a predesigned WPT system, this paper presents the loosely coupled transformer design method to minimize the EMF in the concerned area. The energy storage in the primary and secondary coils is studied for all popular compensation topologies in recently reported research. The coil of the loosely coupled transformer is designed with the S-S compensation topology as an example. The EMF Radiation level is optimized to below the International Commission on Non-Ionizing Radiation Protection guideline in the concerned area. A 3.3-kW WPT system for electric vehicle wireless charging with an LCC-LCC compensation topology is designed with detailed process and experiment results, verifying that the EMF Radiation is controlled as designed. The numerical analysis of human exposure is performed with the finite-element method, and the results show compliance as expected.

  • loosely coupled transformer structure and interoperability study for ev wireless charging systems
    IEEE Transactions on Power Electronics, 2015
    Co-Authors: Wei Zhang, Jeff C White, Arpith Mathew Abraham, Chunting Chris Mi
    Abstract:

    As the wireless power transfer (WPT) technology has been proved to be a convenient and reliable charging method to plug-in hybrid electric vehicles and electric vehicles, the loosely coupled transformer structure and size are the primary and fundamental concern to design an efficient WPT system. In this paper, a double D (DD) coil and a unipolar coil are selected to conduct the study. We focus on the coil structure design to achieve the maximum coupling coefficient as well as efficiency with two situations: 1) with no misalignment, and 2) with a 75-mm door-to-door and 100-mm front-to-back misalignment at which the maximum operating capability can still be achieved. A coil size optimization process is proposed for both the DD coil and the unipolar coil configurations. The relationship between the size of the secondary (receiving) coil, which determines the weight of the pad on the vehicle, and achievable maximum efficiency is studied for both coil topologies. The interoperability between the two coil topologies is studied. The proposed transformer structures with aluminum shielding meet human exposure regulations of the International Commission on Non-Ionizing Radiation Protection guidelines as a foundation. Finally, experiments validated the analyses.

Agnieszka Wolska - One of the best experts on this subject based on the ideXlab platform.

  • occupational exposure to solar ultraviolet Radiation of polish outdoor workers risk estimation method and criterion
    International Journal of Occupational Safety and Ergonomics, 2013
    Co-Authors: Agnieszka Wolska
    Abstract:

    This paper presents occupational skin exposure to solar ultraviolet Radiation (UVR) of 122 Polish outdoor workers in spring and summer. In 65% of the cases, it was significant and exceeded 10 standard erythema doses (SED) during a work shift. The results provided grounds for (a) modifying hazard assessment based on the skin exposure factor proposed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and (b) developing a criterion of risk estimation. The modified method uses the UV index (UVI) instead of the geographical latitude and season factor. The skin exposure factor (Wes) of one is the criterion of risk estimation. Risk is low if the estimated value of Wes does not exceed one. If it does, suitable preventive measures are necessary and a corrected skin exposure factor (Wes*) is calculated to minimize its value to at least one. Risk estimated with that method was high in 67% of the cases.

  • occupational exposure to solar ultraviolet Radiation of polish outdoor workers risk estimation method and criterion
    International Journal of Occupational Safety and Ergonomics, 2013
    Co-Authors: Agnieszka Wolska
    Abstract:

    This paper presents occupational skin exposure to solar ultraviolet Radiation (UVR) of 122 Polish outdoor workers in spring and summer. In 65% of the cases, it was significant and exceeded 10 standard erythema doses (SED) during a work shift. The results provided grounds for (a) modifying hazard assessment based on the skin exposure factor proposed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and (b) developing a criterion of risk estimation. The modified method uses the UV index (UVI) instead of the geographical latitude and season factor. The skin exposure factor (Wes) of one is the criterion of risk estimation. Risk is low if the estimated value of Wes does not exceed one. If it does, suitable preventive measures are necessary and a corrected skin exposure factor (Wes*) is calculated to minimize its value to at least one. Risk estimated with that method was high in 67% of the cases.