In this paper, the author takes the ancient dwellings in Liu Jiaqiao Village as an example to excavate its protection value. Meanwhile, the changing reasons of the dwellings are analyzed. Based on the analysis, the st...In this paper, the author takes the ancient dwellings in Liu Jiaqiao Village as an example to excavate its protection value. Meanwhile, the changing reasons of the dwellings are analyzed. Based on the analysis, the strategies dealing with the phenomenon are proposed from the perspective of protection and inher-itance.展开更多
The persimmon,belonging to the genus Diospyros,is one of the most common fruits with high edible and economic value.China has the largest cultivated area and annual production of persimmons in the world.Pollination-co...The persimmon,belonging to the genus Diospyros,is one of the most common fruits with high edible and economic value.China has the largest cultivated area and annual production of persimmons in the world.Pollination-constant nonastringent(PCNA)persimmon,which has great advantages of natural deastringency and direct edibility,has been a key target for industry development and variety selection worldwide.However,there are still many challenges in the development of persimmons in China;for example,the ineffective cost of artificial deastringency treatment of persimmons,laborious breeding of fine varieties of PCNA persimmon,and severe symptoms of delayed graft-incompatibility.This review summarizes the current status and development of persimmons in China.The current progress on the removal of astringency in persimmons,screening of rootstocks with wide compatibility,and the breeding process of PCNA persimmon is highlighted.This review will help promote the breeding of excellent persimmon varieties and the sustainable development of the persimmon industry in China.展开更多
The data rate of a visible light communication(VLC) system is basically determined by the electrical-to-optical(E-O) bandwidth of its light-emitting diode(LED) source. In order to break through the intrinsic limitatio...The data rate of a visible light communication(VLC) system is basically determined by the electrical-to-optical(E-O) bandwidth of its light-emitting diode(LED) source. In order to break through the intrinsic limitation of the carrier recombination rate on E-O bandwidth in conventional c-plane LEDs based on In Ga N quantum wells,a blue micro-LED with an active region of nano-structured In Ga N wetting layer is designed, fabricated, and packaged to realize a high-speed VLC system. The E-O bandwidth of the micro-LED can reach up to 1.3 GHz. Based on this high-speed micro-LED, we demonstrated a data rate of 2 Gbps with a bit error rate(BER) of 1.2×10^(-3) with simple on-off keying signal for a 3-m real-time VLC. In addition, a 4-Gbps VLC system using quadrature phase shift keying-orthogonal frequency-division multiplexing with a BER of 3.2×10^(-3) is also achieved for the same scenario. Among all the point-to-point VLC systems based on a single-pixel LED,this work has the highest distance-bandwidth product of 3 GHz·m and the highest distance-rate product of 12 Gbps·m.展开更多
This paper describes a seamless three-dimensional （3-D） localization and navigation system for smartphones. The smartphone includes an atmospheric pressure sensor to measure the user＇s altitude that is combined wit...This paper describes a seamless three-dimensional （3-D） localization and navigation system for smartphones. The smartphone includes an atmospheric pressure sensor to measure the user＇s altitude that is combined with the outdoor Global Positioning System （GPS） and indoor WiFi-APs localization systems in a seamless 3-D localization system. The smartphone software also provides seamless navigation services by updating map information for both indoor and outdoor locations through the mobile Internet. The indoor floor information calculated from the altitude information is used to project localization anchor nodes, e.g., WiFi-AP, on different floors onto the user＇s floor with an indoor 3-D localization algorithm using projection distances based on a Received Signal Strength （RSS） algorithm. Tests show that the 3-D method reduces systematic errors and achieves much higher accuracy than the traditional two-dimensional localization method.展开更多
文摘In this paper, the author takes the ancient dwellings in Liu Jiaqiao Village as an example to excavate its protection value. Meanwhile, the changing reasons of the dwellings are analyzed. Based on the analysis, the strategies dealing with the phenomenon are proposed from the perspective of protection and inher-itance.
基金supported by the Jiangsu Seed Industry Key Research Program(JBGS[2021]019)the Fundamental Research Funds for the Central Universities(KYZZ2022004)+2 种基金the National Key R&D Program of China(2019YFD1000600)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_0606)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,and the Jiangsu Belt and Road innovation cooperation project(BZ2019012).
文摘The persimmon,belonging to the genus Diospyros,is one of the most common fruits with high edible and economic value.China has the largest cultivated area and annual production of persimmons in the world.Pollination-constant nonastringent(PCNA)persimmon,which has great advantages of natural deastringency and direct edibility,has been a key target for industry development and variety selection worldwide.However,there are still many challenges in the development of persimmons in China;for example,the ineffective cost of artificial deastringency treatment of persimmons,laborious breeding of fine varieties of PCNA persimmon,and severe symptoms of delayed graft-incompatibility.This review summarizes the current status and development of persimmons in China.The current progress on the removal of astringency in persimmons,screening of rootstocks with wide compatibility,and the breeding process of PCNA persimmon is highlighted.This review will help promote the breeding of excellent persimmon varieties and the sustainable development of the persimmon industry in China.
基金National Key Research and Development Program of China(2016YFB0401803)National Natural Science Foundation of China(61822404,61974080)+3 种基金Shenzhen Science and Technology Innovation Commission(JCYJ20180507183815699)Tsinghua-Berkeley Shenzhen Institute(TBSI)Faculty Start-up FundShenzhen Fundamental Research Project(JCYJ20170817161720819)Overseas Research Cooperation Fund of Tsinghua Shenzhen International Graduate School(HW2018003)。
文摘The data rate of a visible light communication(VLC) system is basically determined by the electrical-to-optical(E-O) bandwidth of its light-emitting diode(LED) source. In order to break through the intrinsic limitation of the carrier recombination rate on E-O bandwidth in conventional c-plane LEDs based on In Ga N quantum wells,a blue micro-LED with an active region of nano-structured In Ga N wetting layer is designed, fabricated, and packaged to realize a high-speed VLC system. The E-O bandwidth of the micro-LED can reach up to 1.3 GHz. Based on this high-speed micro-LED, we demonstrated a data rate of 2 Gbps with a bit error rate(BER) of 1.2×10^(-3) with simple on-off keying signal for a 3-m real-time VLC. In addition, a 4-Gbps VLC system using quadrature phase shift keying-orthogonal frequency-division multiplexing with a BER of 3.2×10^(-3) is also achieved for the same scenario. Among all the point-to-point VLC systems based on a single-pixel LED,this work has the highest distance-bandwidth product of 3 GHz·m and the highest distance-rate product of 12 Gbps·m.
基金Supported by the National Natural Science Foundation of China (No.60932005)the Sino-European Cooperation Project (No.2010DFA11680)the Tsinghua Sci-Tech Project (No.2011THZ0)
文摘This paper describes a seamless three-dimensional （3-D） localization and navigation system for smartphones. The smartphone includes an atmospheric pressure sensor to measure the user＇s altitude that is combined with the outdoor Global Positioning System （GPS） and indoor WiFi-APs localization systems in a seamless 3-D localization system. The smartphone software also provides seamless navigation services by updating map information for both indoor and outdoor locations through the mobile Internet. The indoor floor information calculated from the altitude information is used to project localization anchor nodes, e.g., WiFi-AP, on different floors onto the user＇s floor with an indoor 3-D localization algorithm using projection distances based on a Received Signal Strength （RSS） algorithm. Tests show that the 3-D method reduces systematic errors and achieves much higher accuracy than the traditional two-dimensional localization method.
