Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments in these fields have created demands for development of better performance and higher sur...Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments in these fields have created demands for development of better performance and higher surface accuracy. However, low accuracy and low effi- ciency are the common disadvantages for traditional panel alignment and adjustment. In order to improve the surface accuracy of large reflector antenna, a new method is pre- sented to determinate panel adjustment values from far field pattern. Based on the method of Physical Optics （PO）, the effect of panel facet displacement on radiation field value is derived. Then the linear system is constructed between panel adjustment vector and far field pattern. Using the method of Singular Value Decomposition （SVD）, the adjustment value for all panel adjustors are obtained by solving the linear equations. An experiment is conducted on a 3.7 m reflector antenna with 12 segmented panels. The results of simulation and test are similar, which shows that the presented method is feasible. Moreover, thediscussion about validation shows that the method can be used for many cases of reflector shape. The proposed research provides the instruction to adjust surface panels efficiently and accurately.展开更多
Based on the works of Greve and Rahmat-Samii, theelectromagnetic （EM） performance of the reflector antenna withnon-uniform surface errors along radius is further addressed. Amathematical model is developed to descri...Based on the works of Greve and Rahmat-Samii, theelectromagnetic （EM） performance of the reflector antenna withnon-uniform surface errors along radius is further addressed. Amathematical model is developed to describe the weighting functionfor the non-uniform surface errors along radius. Then, somediscussions on the peak gain loss （PGL） and the first sidelobelevel increase （SLLI） caused by the non-uniform surface errors arepresented and several significant radiation characteristics of thereflector with non-uniform errors are pointed out. Last, based onthe proposed model, the weighted root mean square （RMS） valueof the surface errors is produced to evaluate the EM performanceand several representative cases with different non-uniform errorsare presented with good results. Results show that the weightedRMS value should be taken into account for a better quality evaluationof the reflector surface.展开更多
Complex genetic architecture is the major cause of heterogeneity in epilepsy,which poses challenges for accurate diagnosis and precise treatment.A large number of epilepsy candidate genes have been identified from cli...Complex genetic architecture is the major cause of heterogeneity in epilepsy,which poses challenges for accurate diagnosis and precise treatment.A large number of epilepsy candidate genes have been identified from clinical studies,particularly with the widespread use of next-generation sequencing.Validating these candidate genes is emerging as a valuable yet challenging task.Drosophila serves as an ideal animal model for validating candidate genes associated with neurogenetic disorders such as epilepsy,due to its rapid reproduction rate,powerful genetic tools,and efficient use of ethological and electrophysiological assays.Here,we systematically summarize the advantageous techniques of the Drosophila model used to investigate epilepsy genes,including genetic tools for manipulating target gene expression,ethological assays for seizure-like behaviors,electrophysiological techniques,and functional imaging for recording neural activity.We then introduce several typical strategies for identifying epilepsy genes and provide new insights into gene-gene interactions in epilepsy with polygenic causes.We summarize well-established precision medicine strategies for epilepsy and discuss prospective treatment options,including drug therapy and gene therapy for genetic epilepsy based on the Drosophila model.Finally,we also address genetic counseling and assisted reproductive technology as potential approaches for the prevention of genetic epilepsy.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.51490661,51490660,51205301)National Key Basic Research Program of China(973 Program,Grant No.2015CB857100)Special Funding for Key Laboratory of Xinjiang Uygur Autonomous Region,China(Grant No.2014KL012)
文摘Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments in these fields have created demands for development of better performance and higher surface accuracy. However, low accuracy and low effi- ciency are the common disadvantages for traditional panel alignment and adjustment. In order to improve the surface accuracy of large reflector antenna, a new method is pre- sented to determinate panel adjustment values from far field pattern. Based on the method of Physical Optics （PO）, the effect of panel facet displacement on radiation field value is derived. Then the linear system is constructed between panel adjustment vector and far field pattern. Using the method of Singular Value Decomposition （SVD）, the adjustment value for all panel adjustors are obtained by solving the linear equations. An experiment is conducted on a 3.7 m reflector antenna with 12 segmented panels. The results of simulation and test are similar, which shows that the presented method is feasible. Moreover, thediscussion about validation shows that the method can be used for many cases of reflector shape. The proposed research provides the instruction to adjust surface panels efficiently and accurately.
基金supported by the National Basic Research Program of China(973 Program)(2015CB857100)the Foundation for Key Laboratory of Xinjiang Uygur Autonomous Region(2014KL012)+2 种基金the National Natural Science Foundation of China(514906605147534951522507)
文摘Based on the works of Greve and Rahmat-Samii, theelectromagnetic （EM） performance of the reflector antenna withnon-uniform surface errors along radius is further addressed. Amathematical model is developed to describe the weighting functionfor the non-uniform surface errors along radius. Then, somediscussions on the peak gain loss （PGL） and the first sidelobelevel increase （SLLI） caused by the non-uniform surface errors arepresented and several significant radiation characteristics of thereflector with non-uniform errors are pointed out. Last, based onthe proposed model, the weighted root mean square （RMS） valueof the surface errors is produced to evaluate the EM performanceand several representative cases with different non-uniform errorsare presented with good results. Results show that the weightedRMS value should be taken into account for a better quality evaluationof the reflector surface.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,No.2022A1515111123(to JQ)。
文摘Complex genetic architecture is the major cause of heterogeneity in epilepsy,which poses challenges for accurate diagnosis and precise treatment.A large number of epilepsy candidate genes have been identified from clinical studies,particularly with the widespread use of next-generation sequencing.Validating these candidate genes is emerging as a valuable yet challenging task.Drosophila serves as an ideal animal model for validating candidate genes associated with neurogenetic disorders such as epilepsy,due to its rapid reproduction rate,powerful genetic tools,and efficient use of ethological and electrophysiological assays.Here,we systematically summarize the advantageous techniques of the Drosophila model used to investigate epilepsy genes,including genetic tools for manipulating target gene expression,ethological assays for seizure-like behaviors,electrophysiological techniques,and functional imaging for recording neural activity.We then introduce several typical strategies for identifying epilepsy genes and provide new insights into gene-gene interactions in epilepsy with polygenic causes.We summarize well-established precision medicine strategies for epilepsy and discuss prospective treatment options,including drug therapy and gene therapy for genetic epilepsy based on the Drosophila model.Finally,we also address genetic counseling and assisted reproductive technology as potential approaches for the prevention of genetic epilepsy.
