在刚刚过去的2010年末，一款名叫《割绳子》的益智游戏异军突起，冲上了App Store最受欢迎游戏的宝座。在为开发商赚来犬笔钞票的同时，也吸引了不少模仿者，其中有一款就叫做《烧绳子》——Burn the Rope。说是模仿。但其他这两款游戏...在刚刚过去的2010年末，一款名叫《割绳子》的益智游戏异军突起，冲上了App Store最受欢迎游戏的宝座。在为开发商赚来犬笔钞票的同时，也吸引了不少模仿者，其中有一款就叫做《烧绳子》——Burn the Rope。说是模仿。但其他这两款游戏的概念其实不太一样。《烧绳子》的游戏目的很简单，用火把绳子全部烧完。游戏主要利用了iOS设备的重力感应仪，展开更多
A model of magnetic stimulation is presented for analysis of the spatial distributions of the electric field induced by magnetic coils.Dimensionless analysis is introduced and makes the factors influencing the magnitu...A model of magnetic stimulation is presented for analysis of the spatial distributions of the electric field induced by magnetic coils.Dimensionless analysis is introduced and makes the factors influencing the magnitude of electric field into two parts:c (represents the stimulation conditions),and E 0 (reflects the geometry of coil).By 3 D simulation of the induced electric field of two kinds of coils,the effect of magnetic stimulation can be demonstrated and the factors influencing stimulating focality and depth are identified.The principles for determining the electric field magnitude,focality and magnetic stimulation depth when designing a reasonable coil and stimulator and achieving ideal stimulating effect are discussed.展开更多
Due to interaction with the vacuum of the radiation field,a K-type atomic system with near-degenerateexcited and ground levels,which is driven by two strong coherent fields and two weak probe fields,has additional coh...Due to interaction with the vacuum of the radiation field,a K-type atomic system with near-degenerateexcited and ground levels,which is driven by two strong coherent fields and two weak probe fields,has additional coherenceterms—the vacuum-induced coherence (VIC) terms.In this paper,we find that,if the interference is optimized,thetwo-photon absorption properties of this atom system can be significantly modified and electromagnetically-inducedtransparency (EIT) is dependent on this interference.Furthermore,we find that in all the cases the coherence can suppressor enhance the partial two-photon transparency,while the complete transparency window is still strictly preserved,whichmeans that it cannot be affected by the VIC.Another important result is the finding of the crucial role played by therelative phase between the probe and coupling fields:the relative height of absorption peaks can be modulated by therelative phase.The physical interpretation of the phenomena has been given.展开更多
Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data tra...Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data transmission in marine environment detection at home.In order to improve the transmission performance of the system in practical communication system,optimizing the design by directly changing the circuit parameters is time-consuming and expensive.Therefore,a set of inductive coupling transmission channel analysis system is designed based on virtual instrument to improve the transmission rate and reliability of inductive coupling transmission system.The bit error rate of channel system at different frequency and noise levels are tested by using three kinds of digital modulation mode including amplitude shift keying(ASK),frequency shift keying(FSK)and differential phase shift keying(DPSK),taking square wave and sine wave as a carrier.Finally,the sine wave is selected to be carrier signal and DPSK is chosen to be modulation mode.The reliable transmission of signal with the error rate less than0.005and the transmission rate of9600bps,at the noise level of-10dB,is realized and verified by the debugging circuit experiments with multi-nodes in the laboratory.The study provides an important experimental evidence for improving signal transmission reliability of inductive coupling transmission system.展开更多
The mechanical and strain sensing properties of carbon nanotube composite yarns （CNTs/PDMS） with different weight percent of PDMS were studied. The CNT/PDMS composite yarn was prepared by infiltration method. Pictur...The mechanical and strain sensing properties of carbon nanotube composite yarns （CNTs/PDMS） with different weight percent of PDMS were studied. The CNT/PDMS composite yarn was prepared by infiltration method. Pictures of diameter of CNT composite yarns were obtained though polarized light microscope. Resistance change values of CNT composites under stretching were obtained though the single fiber strength tester and digital multimeter and related mechanical, electrical software. The changes of mechanical properties. electrical properties and sensing pertbrmance of pure and composite CNT yarns were discussed and analyzed. The results showed that the strength of CNT yarn declined after it was composited with PDMS polymer. In addition, the conductivity and sensing performance of CNT yarns improved significantly. The most suitable CNT composite yam occurs at PDMS mass fraction of 1% when strength and sensing properties were all considered.展开更多
文摘在刚刚过去的2010年末，一款名叫《割绳子》的益智游戏异军突起，冲上了App Store最受欢迎游戏的宝座。在为开发商赚来犬笔钞票的同时，也吸引了不少模仿者，其中有一款就叫做《烧绳子》——Burn the Rope。说是模仿。但其他这两款游戏的概念其实不太一样。《烧绳子》的游戏目的很简单，用火把绳子全部烧完。游戏主要利用了iOS设备的重力感应仪，
文摘A model of magnetic stimulation is presented for analysis of the spatial distributions of the electric field induced by magnetic coils.Dimensionless analysis is introduced and makes the factors influencing the magnitude of electric field into two parts:c (represents the stimulation conditions),and E 0 (reflects the geometry of coil).By 3 D simulation of the induced electric field of two kinds of coils,the effect of magnetic stimulation can be demonstrated and the factors influencing stimulating focality and depth are identified.The principles for determining the electric field magnitude,focality and magnetic stimulation depth when designing a reasonable coil and stimulator and achieving ideal stimulating effect are discussed.
基金National Natural Science Foundation of China under Grant Nos.90503088 and 10775100the Fund of Theoretical Nuclear Center of HIRFL of China
文摘Due to interaction with the vacuum of the radiation field,a K-type atomic system with near-degenerateexcited and ground levels,which is driven by two strong coherent fields and two weak probe fields,has additional coherenceterms—the vacuum-induced coherence (VIC) terms.In this paper,we find that,if the interference is optimized,thetwo-photon absorption properties of this atom system can be significantly modified and electromagnetically-inducedtransparency (EIT) is dependent on this interference.Furthermore,we find that in all the cases the coherence can suppressor enhance the partial two-photon transparency,while the complete transparency window is still strictly preserved,whichmeans that it cannot be affected by the VIC.Another important result is the finding of the crucial role played by therelative phase between the probe and coupling fields:the relative height of absorption peaks can be modulated by therelative phase.The physical interpretation of the phenomena has been given.
基金National Natural Science Foundation of China(No.41506122)
文摘Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data transmission in marine environment detection at home.In order to improve the transmission performance of the system in practical communication system,optimizing the design by directly changing the circuit parameters is time-consuming and expensive.Therefore,a set of inductive coupling transmission channel analysis system is designed based on virtual instrument to improve the transmission rate and reliability of inductive coupling transmission system.The bit error rate of channel system at different frequency and noise levels are tested by using three kinds of digital modulation mode including amplitude shift keying(ASK),frequency shift keying(FSK)and differential phase shift keying(DPSK),taking square wave and sine wave as a carrier.Finally,the sine wave is selected to be carrier signal and DPSK is chosen to be modulation mode.The reliable transmission of signal with the error rate less than0.005and the transmission rate of9600bps,at the noise level of-10dB,is realized and verified by the debugging circuit experiments with multi-nodes in the laboratory.The study provides an important experimental evidence for improving signal transmission reliability of inductive coupling transmission system.
文摘The mechanical and strain sensing properties of carbon nanotube composite yarns （CNTs/PDMS） with different weight percent of PDMS were studied. The CNT/PDMS composite yarn was prepared by infiltration method. Pictures of diameter of CNT composite yarns were obtained though polarized light microscope. Resistance change values of CNT composites under stretching were obtained though the single fiber strength tester and digital multimeter and related mechanical, electrical software. The changes of mechanical properties. electrical properties and sensing pertbrmance of pure and composite CNT yarns were discussed and analyzed. The results showed that the strength of CNT yarn declined after it was composited with PDMS polymer. In addition, the conductivity and sensing performance of CNT yarns improved significantly. The most suitable CNT composite yam occurs at PDMS mass fraction of 1% when strength and sensing properties were all considered.
