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近年来电池储能以其响应速度快、能量密度高等优点，在电力系统中发挥重要作用。为满足实际应用的要求，电池储能系统需要将电池或电池组并联从而达到较高的可用容量，但并联电池在实际中受内阻、容量、荷电状态 （SOC）等影响将出现电流不平衡现象，一定程度上制约了电池充放电电流和使用条件，影响了电池性能。针对并联电池组支路电流采集过程繁琐且状态估计复杂的情况，以电池的二阶等效电路为基础，结合回路电流法建立了并联电池组的仿真模型。模型能够根据锂电池的性能参数及状态方程实现并联支路电流的计算，进而估计并联电池组的状态，省去了对并联支路电流的检测环节。同时重点研究了并联电池组的支路不均衡电流现象，以磷酸铁锂电池为例，分析了并联电池组的充电特性。针对并联电池组的支路不均衡电流影响因素较为复杂、难以解耦的特性，采用控制变量法，通过模型详细分析了内阻、容量、初始SOC等因素对支路电流点的影响，为并联电池组的设计、成组优化及性能分析提供了参考。

针对射频功率放大器的非线性问题,提出一种基于两个复量多项式的模拟预失真电路,并根据射频功率放大器的响应用LMS（最小均方）算法自适应优化多项式的系数,从而使功率放大器的线性性能达到最佳。该预失真器的优点是电路简单,运算量少,适用于宽带通信。基于双频信号和WCDMA（宽带码分多址）信号对该预失真器进行了仿真测试。实验结果表明,该预失真线性化方法对交调失真分量抑制效果明显,ACPR（邻信道功率比）可改善至56.1dB,对功率放大器的非线性具有良好的补偿效果。

Rice (Orysa sativa L.) is one of the most important food crops in China, playing a major role in guaranteeing food security. Thanks to the development of science and technology, especially the progress of rice breeding technology, there have been two rounds of substantial increase in China’s rice yield since the large-scale application of dwarf rice breeding and hybrid rice technology. Consumer demand for rice varieties and rice products is becoming increasingly diversified in the new era, and the current efficiency of rice breeding is still not satisfactory enough to meet future demand. As a self-pollinated crop, rice requires multiple generations of continuous self-crossing to achieve genetic homozygosis and stability in segregating generations during the breeding process. However, the long growth cycle of rice in paddy field and the difficulty of year-round planting have led to a long breeding cycle, which has become one of the crucial bottlenecks in rice breeding. Speed breeding is a new technology rising in recent years that promotes crop growth, flowering and maturation through comprehensive measures such as environmental regulation and growth manipulation to expedite the crop generation advance, which can shorten the “seed to seed” cycle and realize multi-generation breeding annually, and promises to significantly shorten the breeding cycle and improve the breeding efficiency. In this review, we focus on the rice crop and systematically describe the research status and progresses of speed breeding in rice in terms of the rise of crop speed breeding technology, the research overview of rice speed breeding, key genes in rice speed breeding, environmental factors affecting the rice flowering and maturation, and the incorporation of speed breeding and modern breeding technology. Further, we discuss and look forward to the challenges and key directions of future research in this field, aiming to promote the rapid development and application of speed breeding technology in rice, improve the efficiency of rice breeding, and provide useful references for guaranteeing food security and sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Geography is the property of Tropical Geography Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Compared to the rest of the world, Asia shows greater differences in socioeconomic and political systems among its countries. Such differences are not conducive to regional integration. It is my view that the integration of the world is a desirable goal and is inevitable. Of course, such a process takes a long time and Asia is no exception. In order to realize the integration of Asia, I argue that Asia needs to achieve what I call Asianization, a process that will remove ideologies (de-ideology), facilitate communication, and promote shared value within Asia. All these will lead to the integration of Asia. Finally, I propose that the East Asian region build a “Network of West Pacific Metropolitan Areas” to institutionalize the exchange within Asia. [ABSTRACT FROM AUTHOR]

With the progress of technology and the depletion of shallow mineral resources, the development and utilization of deep mineral resources will become reality. The deep rocks have complex physical and mechanics properties, and they are often in cycle loading stress condition. The larger pressure of deep groundwater is one of the main safety hazards in deep coal mines. As one of the most common rock types, it is significant to study the mechanical properties and permeability evolution of the roof sandstone for the exploitation of deep mineral resources. In this paper, the roof sandstone of Pingmei 12th Coal Mine with a depth of about 1 050 m has been investigated. The sandstone permeability evolution under stress is researched by cyclic loading acoustic emission (AE) permeability experiment. Based on the stress-strain and damage characteristics, dissipative energy density ratio, the growth rate of accumulated acoustic emission events, the features of fracture surface under different confining pressures, the permeability evolution of the roof sandstone under cycle loading has been summarized. Experimental results show that the effect of stress on rock can be divided into compaction and fracturing. The low stress mainly acts as compaction. The stress, which increases to more than 60% of the yield strength, mainly acts as fracturing. Permeability decreases under compaction of stress and increases under fracturing of stress. The dissipative energy density ratio and damage variable D of the rock sample decreases under compaction and increases under fracturing, which are both positively correlated with permeability evolution. During the whole experiment, the confining pressure acts as a compaction on the rock sample, and as the confining pressure increases, the permeability decreases to a greater extent. The failure mode of the roof sandstone has a significant effect on the permeability at the time of failure. The rupture angle of rock sample decreases with the increase of confining pressure. When the rock sample is destroyed, there are two forms of axial through crack and transverse through crack. When the axial through crack is generated, the permeability will be much larger than the initial permeability. The permeability of the transverse through crack will not change significantly. Based on the permeability evolution of five rock samples, rock permeability has four distinct phase characteristics under stepwise cyclic loading and unloading. The permeability decreases by compaction in the cycle of low stress. With the increase of cyclic stress, the permeability will increase under the fracture and damage. The permeability increases sharply, with the fracture face generated. The stress is greatly reduced after the failure, and the permeability decreases again due to the compaction. [ABSTRACT FROM AUTHOR]