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Jianqing Wang

Bio: Jianqing Wang is an academic researcher from Nagoya Institute of Technology. The author has contributed to research in topics: Ultra-wideband & Bit error rate. The author has an hindex of 29, co-authored 238 publications receiving 3096 citations. Previous affiliations of Jianqing Wang include Tohoku University & Korea Maritime and Ocean University.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the specific absorption rate (SAR) in the human head was determined using the finite-difference time-domain (FDTD) method, while a bioheat equation was numerically solved also using the FDTD method.
Abstract: Temperature rises in the human head for portable telephones were computed with an anatomically based head model at 900 MHz and 1.5 GHz. The specific absorption rate (SAR) in the human head was determined using the finite-difference time-domain (FDTD) method, while a bioheat equation was numerically solved also using the FDTD method. The portable telephone was modeled by a quarter-wavelength monopole antenna on a dielectric covered metal box. The source geometries considered were the telephone barely touching the ear and the telephone pressing the ear, both having a vertical alignment at the side of the head. The antenna output power was set to be consistent with the portable telephones of today: 0.6 W at 900 MHz and 0.27 W at 1.5 GHz. Computed results show that a phone time of 6-7 min yields a temperature rise of approximately 90% of the steady-state value. Application of the ANSZ/IEEE safety guidelines restricting the 1-g-averaged spatial peak SAR to 1.6 W/kg results in the maximum temperature rise in the brain of 0.06/spl deg/C, and application of the ICNIRP/Japan safety guidelines restricting the 10-g-averaged spatial peak SAR to 2 W/kg results in the maximum temperature rise in the brain of 0.11/spl deg/C, both at 900 MHz and 1.5 GHz.

265 citations

Journal ArticleDOI
TL;DR: In this article, specific absorption rates (SAR) determined computationally in the specific anthropomorphic mannequin (SAM) and anatomically correct models of the human head when exposed to a mobile phone model are compared as part of a study organized by IEEE Standards Coordinating Committee 34, Sub-Committee 2, and Working Group 2.
Abstract: The specific absorption rates (SAR) determined computationally in the specific anthropomorphic mannequin (SAM) and anatomically correct models of the human head when exposed to a mobile phone model are compared as part of a study organized by IEEE Standards Coordinating Committee 34, Sub-Committee 2, and Working Group 2, and carried out by an international task force comprising 14 government, academic, and industrial research institutions. The detailed study protocol defined the computational head and mobile phone models. The participants used different finite-difference time-domain software and independently positioned the mobile phone and head models in accordance with the protocol. The results show that when the pinna SAR is calculated separately from the head SAR, SAM produced a higher SAR in the head than the anatomically correct head models. Also the larger (adult) head produced a statistically significant higher peak SAR for both the 1- and 10-g averages than did the smaller (child) head for all conditions of frequency and position.

207 citations

Journal ArticleDOI
TL;DR: Using the frequency-dependent finite-difference time domain method and a realistic human body model, an on-body propagation model is derived and the model parameters for some representative transmission links on the human body are determined.
Abstract: On-body area ultrawideband (UWB) communication is of high importance for promising new biomedical applications. However, there are currently few measurements or models describing on-body area propagation channels which put an emphasis on various body postures. Using the frequency-dependent finite-difference time domain (FDTD) method and a realistic human body model, we simulate various body postures for modeling on-body channels. Based on the FDTD numerical results, we derive an on-body propagation model and determine the model parameters for some representative transmission links on the human body. A good match is obtained between the data derived from FDTD and the statistically implemented models in terms of key communication metrics. In addition, for the chest-to-right-waist transmission link, an experiment is performed in order to verify the results from the FDTD method, and it is found that the model parameters agree well between the two approaches.

137 citations

Journal ArticleDOI
TL;DR: This article outlines some of the research that has been done to obtain accurate propagation models supporting the standardization of implant communication in BANs and current research to enhance the channel models of IEEE Std 802.15.6.
Abstract: A body area network is a radio communication protocol for short-range, low-power, and highly reliable wireless communication for use on the surface, inside, or in the peripheral proximity of the human body Combined with various biomedical sensors, BANs enable realtime collection and monitoring of physiological signals Therefore, it is regarded as an important technology for the treatment and prevention of chronic diseases, and health monitoring of the elderly The IEEE 802 LAN/MAN Standards Committee approved Task Group TG156 in December 2007 As a result of more than four years of effort, in February 2012, TG156 published the first international standard for BANs, IEEE Std 802156 Throughout the development of this standard, ample collaboration between the standardization group and the research community was required In particular, understanding the radio propagation mechanisms for BANs demanded the most research effort Technical challenges were magnified for the case of implant communication because of the impossibility of conducting in-body measurements with human subjects Therefore, research in this field had to make use of intricate computer simulations This article outlines some of the research that has been done to obtain accurate propagation models supporting the standardization of implant communication in BANs Current research to enhance the channel models of IEEE Std 802156 through the use of ultra wideband signals for implantable devices along with physical measurements in animals is also presented

127 citations

Journal ArticleDOI
TL;DR: Two kinds of children's models from a Japanese adult head model are developed, based on Japanese children's statistical data on external shapes of heads, which suggest that the contradictory conclusions drawn by the above two groups may be due to the different conditions in their numerical peak SAR calculations.
Abstract: The controversy on the dosimetry in children's heads for mobile telephones is still inconsistent Gandhi's group [1996, 2002] reported a considerable increase of the spatial peak specific absorption rate (SAR) in children's heads, while Kuster's group [1998] claimed that there was not a significant difference in the SAR between children and adults In this paper, based on Japanese children's statistical data on external shapes of heads, we developed two kinds of children's models from a Japanese adult head model Using the children's head models, we calculated the local peak SAR under the same conditions as those previously employed by Gandhi's and Kuster's groups Compared to the local peak SAR in the adult head model, we found a considerable increase in the children's heads when we fixed the output power of the monopole-type antenna, but no significant differences when we fixed the effective current of the dipole-type antenna This finding suggests that the contradictory conclusions drawn by the above two groups may be due to the different conditions in their numerical peak SAR calculations

117 citations


Cited by
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Journal ArticleDOI
06 Jun 1986-JAMA
TL;DR: The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or her own research.
Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

7,563 citations

Journal ArticleDOI
TL;DR: The goal is development of a cloud and cloud shadow detection algorithm suitable for routine usage with Landsat images and as high as 96.4%.

1,620 citations

01 Jan 2007
TL;DR: In this paper, the authors provide updates to IEEE 802.16's MIB for the MAC, PHY and asso-ciated management procedures in order to accommodate recent extensions to the standard.
Abstract: This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

1,481 citations

Journal ArticleDOI
TL;DR: All tissues and organs were reconstructed as three-dimensional unstructured triangulated surface objects, yielding high precision images of individual features of the body, which greatly enhances the meshing flexibility and the accuracy in comparison with the traditional voxel-based representation of anatomical models.
Abstract: The objective of this study was to develop anatomically correct whole body human models of an adult male (34 years old), an adult female (26 years old) and two children (an 11-year-old girl and a six-year-old boy) for the optimized evaluation of electromagnetic exposure. These four models are referred to as the Virtual Family. They are based on high resolution magnetic resonance (MR) images of healthy volunteers. More than 80 different tissue types were distinguished during the segmentation. To improve the accuracy and the effectiveness of the segmentation, a novel semi-automated tool was used to analyze and segment the data. All tissues and organs were reconstructed as three-dimensional (3D) unstructured triangulated surface objects, yielding high precision images of individual features of the body. This greatly enhances the meshing flexibility and the accuracy with respect to thin tissue layers and small organs in comparison with the traditional voxel-based representation of anatomical models. Conformal computational techniques were also applied. The techniques and tools developed in this study can be used to more effectively develop future models and further improve the accuracy of the models for various applications. For research purposes, the four models are provided for free to the scientific community.

1,347 citations