The radiative transfer is one of the significant theories that describe the processes of scattering, emission, and absorption of electromagnetic radiant intensity through scattering medium. It is the basis of the stud...The radiative transfer is one of the significant theories that describe the processes of scattering, emission, and absorption of electromagnetic radiant intensity through scattering medium. It is the basis of the study on the quan-titative remote sensing. In this paper, the radiative characteristics of soil, vegetation, and atmosphere were described respectively. The numerical solution of radiative transfer was accomplished by Successive Orders of Scattering (SOS). A radiative transfer model for simulating microwave brightness temperature over land surfaces was constructed, de-signed, and implemented. Analyzing the database generated from soil-vegetation-atmosphere radiative transfer model under Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) configuration showed that the atmospheric effects on microwave brightness temperature should not be neglected, particularly for higher frequency, and can be parameterized. At the same time, the relationship between the emissivities of the different channels was developed. The study results will promote the development of algorithm to retrieve geophysical parameters from mi-crowave remotely sensed data.展开更多
Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential p...Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90° in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90° broadband differential phase shifter are presented.展开更多
Objective:The aim of our study was to investigate the lymph node metastasis of mesorectum and ischiorectal foss in ultra-low rectal cancer and its influence on the surgical procedure selection.Methods:Large slices and...Objective:The aim of our study was to investigate the lymph node metastasis of mesorectum and ischiorectal foss in ultra-low rectal cancer and its influence on the surgical procedure selection.Methods:Large slices and tissue microarray technology were used to detect metastasis lymph nodes from 23 dissected specimens of ultra-low rectal cancer.Results:415 lymph nodes were detected in the 23 specimens.169 and 59 lymph nodes were metastasis and micrometastasis, respectively.Twelve specimens were diagnosed with lymph node metastasis, while other 4 specimens were with lymph node micro-metastasis.There were 29.0% (49/169) and 17.2% (29/169) metastatic lymph nodes located in the outer and anterior region of mesorectum.There were 2 cases with ischiorectal fossa lymph node metastasis and 1 case with micrometastasis.The 3 metastatic cases were only 13% (13/23) of all the 23 cases.Conclusion:There is regional lymph node metastasis existing in ultra-low rectal cancer.The metastatic incidences in distal mesorectum and ischiorectal fossa are relatively low.Considering Miles operation as the standard surgical procedure for ultra-low rectal cancer should be evaluated renewedly.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 40425012)"Hundred Talent" Program of Chinese Academy of Sciences
文摘The radiative transfer is one of the significant theories that describe the processes of scattering, emission, and absorption of electromagnetic radiant intensity through scattering medium. It is the basis of the study on the quan-titative remote sensing. In this paper, the radiative characteristics of soil, vegetation, and atmosphere were described respectively. The numerical solution of radiative transfer was accomplished by Successive Orders of Scattering (SOS). A radiative transfer model for simulating microwave brightness temperature over land surfaces was constructed, de-signed, and implemented. Analyzing the database generated from soil-vegetation-atmosphere radiative transfer model under Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) configuration showed that the atmospheric effects on microwave brightness temperature should not be neglected, particularly for higher frequency, and can be parameterized. At the same time, the relationship between the emissivities of the different channels was developed. The study results will promote the development of algorithm to retrieve geophysical parameters from mi-crowave remotely sensed data.
基金Project supported by the National Basic Research Program (973) of China (No. 2004CB719802)the National Natural Science Founda-tion of China (No. 60378037)the Science and Technology Department of Zhejiang Province, China (No. 2005C31004)
文摘Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90° in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90° broadband differential phase shifter are presented.
文摘Objective:The aim of our study was to investigate the lymph node metastasis of mesorectum and ischiorectal foss in ultra-low rectal cancer and its influence on the surgical procedure selection.Methods:Large slices and tissue microarray technology were used to detect metastasis lymph nodes from 23 dissected specimens of ultra-low rectal cancer.Results:415 lymph nodes were detected in the 23 specimens.169 and 59 lymph nodes were metastasis and micrometastasis, respectively.Twelve specimens were diagnosed with lymph node metastasis, while other 4 specimens were with lymph node micro-metastasis.There were 29.0% (49/169) and 17.2% (29/169) metastatic lymph nodes located in the outer and anterior region of mesorectum.There were 2 cases with ischiorectal fossa lymph node metastasis and 1 case with micrometastasis.The 3 metastatic cases were only 13% (13/23) of all the 23 cases.Conclusion:There is regional lymph node metastasis existing in ultra-low rectal cancer.The metastatic incidences in distal mesorectum and ischiorectal fossa are relatively low.Considering Miles operation as the standard surgical procedure for ultra-low rectal cancer should be evaluated renewedly.