Bitter gourd,with its narrow genetic background and rich sexual type,is a preferred material to be used to study the gender differentiation of flower buds of monoecious plants.This article is a review of studies on th...Bitter gourd,with its narrow genetic background and rich sexual type,is a preferred material to be used to study the gender differentiation of flower buds of monoecious plants.This article is a review of studies on the gender differentiation of flower buds of bitter gourd,from morphology to cytology,from classical genetics to molecular biology,and the mechanism by which it is regulated.The recent rapid development of whole genome sequencing and high throughput sequencing provides a novel approach to the study of the gender differentiation of flower buds of bitter gourd.The study of the gender differentiation of flower buds of bitter gourd can provide references for the regulation of gender differentiation and molecular breeding of bitter gourd.展开更多
Variable-air-volume (VAV) air-conditioning system is a multi-variable system and has multi coupling control loops. While all of the control loops are working together, they interfere and influence each other. A multiv...Variable-air-volume (VAV) air-conditioning system is a multi-variable system and has multi coupling control loops. While all of the control loops are working together, they interfere and influence each other. A multivariable decoupling PID controller is designed for VAV air-conditioning system. Diagonal matrix decoupling method is employed to eliminate the coupling between the loop of supply air temperature and that of thermal-space air temperature. The PID controller parameters are optimized by means of an improved genetic algorithm in floating point representations to obtain better performance. The population in the improved genetic algorithm mutates before crossover, which is helpful for the convergence. Additionally the micro mutation algorithm is proposed and applied to improve the convergence during the later evolution. To search the best parameters, the optimized parameters ranges should be amplified 10 times the initial ideal parameters. The simulation and experiment results show that the decoupling control system is effective and feasible. The method can overcome the strong coupling feature of the system and has shorter governing time and less over-shoot than non-optimization PID control.展开更多
Since low bit-rate speech codecs used for voice over internet protocol （VolP）, such as iLBC （internet low bit-rate codec）, G.723.1 and G.729A, have less redundancy due to high compression, it is more challenging t...Since low bit-rate speech codecs used for voice over internet protocol （VolP）, such as iLBC （internet low bit-rate codec）, G.723.1 and G.729A, have less redundancy due to high compression, it is more challenging to embed information in low bit-rate speech streams of VolP. In this study, a new method is proposed for steganography in low bit-rate speech streams of VolP. The core idea of this method is setting up a graph model for the codebook space of the quantizer. Based on the graph model, the method realises a quantization index modulation （QIM）-controlled algorithm for partitioning the codebook space. It can be proved that this method can minimize signal distortion while steganography taking place. Taking into account codeword partition balance and partition diversity, the proposed steganographic algorithm was based on QIM controlled by secret keys, i.e., mapping the ways of codebook division into secret keys, thereby significantly improving the undetectability and robustness of VolP steganography. Performance measurements and steganalysis experiments showed that the proposed QIM-controlled steganographic algorithm was more secure and robust than the QIM algorithm, the conventional RANDOM algorithm and the original codebook algorithm.展开更多
ZnO is a typical direct wide-bandgap semiconductor material, which has various morphologies and unique physical and chemical properties, and is widely used in the fields of energy, information technology, biomedicine,...ZnO is a typical direct wide-bandgap semiconductor material, which has various morphologies and unique physical and chemical properties, and is widely used in the fields of energy, information technology, biomedicine, and others. The precise design and controllable fabrication of nanostructures have gradually become important avenues to further enhancing the performance of Zn O-based functional nanodevices. This paper introduces the continuous development of patterning technologies, provides a comprehensive review of the optical lithography and laser interference lithography techniques for the controllable fabrication of Zn O nanostructures, and elaborates on the potential applications of such patterned Zn O nanostructures in solar energy, water splitting, light emission devices, and nanogenerators. Patterned Zn O nanostructures with highly controllable morphology and structure possess discrete three-dimensional space structure, enlarged surface area, and improved light capture ability, which realize the efficient carrier regulation,achieve highly efficient energy conversion, and meet the diverse requirements of functional nanodevices. The patterning techniques proposed for the precise design of Zn O nanostructures not only have important guiding significance for the controllable fabrication of complex nanostructures of other materials, but also open up a new route for the further development of functional nanostructures.展开更多
基金Supported by the National Natural Science Foundation of China(31560562)the National Special Fund Project for the Construction of a Modern Agricultural Industry Technology System(CARS-23)+1 种基金the Innovation Fund Project of Jiangxi Academy of Agricultural Sciences(2014CQN003)the Special Fund for Cooperative Innovation of Modern Agricultural Research in Jiangxi Province(JXXTCX2015005)~~
文摘Bitter gourd,with its narrow genetic background and rich sexual type,is a preferred material to be used to study the gender differentiation of flower buds of monoecious plants.This article is a review of studies on the gender differentiation of flower buds of bitter gourd,from morphology to cytology,from classical genetics to molecular biology,and the mechanism by which it is regulated.The recent rapid development of whole genome sequencing and high throughput sequencing provides a novel approach to the study of the gender differentiation of flower buds of bitter gourd.The study of the gender differentiation of flower buds of bitter gourd can provide references for the regulation of gender differentiation and molecular breeding of bitter gourd.
基金Supported by Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education of China
文摘Variable-air-volume (VAV) air-conditioning system is a multi-variable system and has multi coupling control loops. While all of the control loops are working together, they interfere and influence each other. A multivariable decoupling PID controller is designed for VAV air-conditioning system. Diagonal matrix decoupling method is employed to eliminate the coupling between the loop of supply air temperature and that of thermal-space air temperature. The PID controller parameters are optimized by means of an improved genetic algorithm in floating point representations to obtain better performance. The population in the improved genetic algorithm mutates before crossover, which is helpful for the convergence. Additionally the micro mutation algorithm is proposed and applied to improve the convergence during the later evolution. To search the best parameters, the optimized parameters ranges should be amplified 10 times the initial ideal parameters. The simulation and experiment results show that the decoupling control system is effective and feasible. The method can overcome the strong coupling feature of the system and has shorter governing time and less over-shoot than non-optimization PID control.
基金the National Natural Science Foundation of China(Grant Nos 61271392,U1405254,U1536113,U1536207&U1536115)
文摘Since low bit-rate speech codecs used for voice over internet protocol （VolP）, such as iLBC （internet low bit-rate codec）, G.723.1 and G.729A, have less redundancy due to high compression, it is more challenging to embed information in low bit-rate speech streams of VolP. In this study, a new method is proposed for steganography in low bit-rate speech streams of VolP. The core idea of this method is setting up a graph model for the codebook space of the quantizer. Based on the graph model, the method realises a quantization index modulation （QIM）-controlled algorithm for partitioning the codebook space. It can be proved that this method can minimize signal distortion while steganography taking place. Taking into account codeword partition balance and partition diversity, the proposed steganographic algorithm was based on QIM controlled by secret keys, i.e., mapping the ways of codebook division into secret keys, thereby significantly improving the undetectability and robustness of VolP steganography. Performance measurements and steganalysis experiments showed that the proposed QIM-controlled steganographic algorithm was more secure and robust than the QIM algorithm, the conventional RANDOM algorithm and the original codebook algorithm.
基金supported by the National Key Research and Development Program of China(2013CB932602 and 2016YFA0202701)the Program of Introducing Talents of Discipline to Universities(B14003)+2 种基金the National Natural Science Foundation of China(51527802,51232001,51372020 and 51602020)Beijing Municipal Science&Technology Commission(Z151100003315021)China Postdoctoral Science Foundation(2016M600039)
文摘ZnO is a typical direct wide-bandgap semiconductor material, which has various morphologies and unique physical and chemical properties, and is widely used in the fields of energy, information technology, biomedicine, and others. The precise design and controllable fabrication of nanostructures have gradually become important avenues to further enhancing the performance of Zn O-based functional nanodevices. This paper introduces the continuous development of patterning technologies, provides a comprehensive review of the optical lithography and laser interference lithography techniques for the controllable fabrication of Zn O nanostructures, and elaborates on the potential applications of such patterned Zn O nanostructures in solar energy, water splitting, light emission devices, and nanogenerators. Patterned Zn O nanostructures with highly controllable morphology and structure possess discrete three-dimensional space structure, enlarged surface area, and improved light capture ability, which realize the efficient carrier regulation,achieve highly efficient energy conversion, and meet the diverse requirements of functional nanodevices. The patterning techniques proposed for the precise design of Zn O nanostructures not only have important guiding significance for the controllable fabrication of complex nanostructures of other materials, but also open up a new route for the further development of functional nanostructures.
