The nonlinear governing equations of the liquid sloshing modals in a cylindrical storage tank are established. Through analytical analysis, the analytical expressions of the solutions of this kind of system are obtain...The nonlinear governing equations of the liquid sloshing modals in a cylindrical storage tank are established. Through analytical analysis, the analytical expressions of the solutions of this kind of system are obtained. With different parameters, the dynamical behaviors of the solutions are different from the trivial ones. To prevent system instability, two selection principles that the stiffness equations are positive-definite and the nonlinear terms of the system are not regenerative elements are given. Meanwhile, numerical simulations are also given, which confirm the analytical results.展开更多
The water-filling algorithm enables an energy-efficient OFDM-based transmitter by maximizing the capacity of a frequency selective fading channel. However, this optimal strategy requires the perfect channel state info...The water-filling algorithm enables an energy-efficient OFDM-based transmitter by maximizing the capacity of a frequency selective fading channel. However, this optimal strategy requires the perfect channel state information at the transmitter that is not realistic in wireless applications. In this paper, we propose opportunistic error correction to maximize the data rate of OFDM systems without this limit. The key point of this approach is to reduce the dynamic range of the channel by discarding a part of the channel in deep fading. Instead of decoding all the information from all the sub-channels, we only recover the data via the strong sub-channels. Just like the water-filling principle, we increase the data rate over the stronger sub-channels by sacrificing the weaker sub-channels. In such a case, the total data rate over a frequency selective fading channel can be increased. Correspondingly, the noise floor can be increased to achieve a certain data rate compared to the traditional coding scheme. This leads to an energy-efficient receiver. However, it is not clear whether this method has advantages over the joint coding scheme in the narrow-band wireless system (e.g. the channel with a low dynamic range), which will be investigated in this paper.展开更多
Where hydraulic characteristics of ship lock filling and emptying system are concerned, there are much bigger differences between prototype and model experiments. Based on the results of the prototype experiments fur ...Where hydraulic characteristics of ship lock filling and emptying system are concerned, there are much bigger differences between prototype and model experiments. Based on the results of the prototype experiments fur the Three Gorges Project （TGP）, experiments on the feedback model were conducted of the ship-lock filling and emptying system, by means of technologies of drag reduction, under similar conditions as the operation of the prototype project. The experimental results show that the difference of drag co efficient reached-44% hetween the prototype and the model for the filling and emptying system of the ship-lock No. 3 for TGP and the difference of discharge coefficient was ahout 33% between them. The technologies of drag reduction are more efficient in the simulation of a ship lock filling and emptying system in order to he consistent for discharge, water level, time average pressure and pulsating pressure between prototypes and models.展开更多
基金Supported by a research grant(3 P05D 054 24)from the Ministry of Scientific Research and Information Technology(formerly:State Committee For Scientific Research)of the Republic of Poland-contract #0617/P05/2003/24
文摘瞄准：在一个简单重复的措施学习协议的框架以内评估固体的基于测试的测量分阶段执行胃的倒空的修改 13C 呼吸(GE ) 的重制度。方法：12 个健康题目(6 女性和 6 男性，意味着年龄 24.9+/-0.7 年) 被招募经历三相同 GE 考试。在六个题目，开始的二考试被执行 2 d 分开，并且第三个会议从第二个在 19.5 d (范围 18-20 d ) 的中部的间隔被执行。在六个题目，开始的二大小被拆开 20 d (中部，范围：17-23 d ) ，而第三个会议发生了在第二以后的 2 d。在稳固的饭(378 千卡) 的吸入以后收集在前并且在六个小时期间的吐气的空气的探针用 75 microL (68 mg ) 标记 13C-octanoic 酸，与非散的同位素选择的红外线的分光术 NDIRS 仪器为 13CO2 丰富被测量。结果：为配对的考试考虑变化的系数， GE 测量的短期的重制度比中期的稍微然而并非显著地好：7.7% 和 11.2% 为迟滞期(T 落后) ， 7.3% 和 10.9% 为倒空时间(T1/2 ) 的胃的一半。在在在 12 配对的考试的 P=0.05 水平可检测的 GE 参数的最少的差别是为 T 落后的 9.6 和 15.6 min，为由到三星期的时间的一两个 two-day 的 T1/2 的 11.6 和 19.7 min 分别地豁开。结论：呼吸的便宜修正测试包含 13C-octanoic 酸和 NDIRS 的更低的剂量，显示固体的胃的倒空的测量的好短期、中期的重制度，以及敏感。
基金Project supported by the National Natural Science Foundation of China(Grant No.10632040)the Independent Innovation Foundation of Tianjin University
文摘The nonlinear governing equations of the liquid sloshing modals in a cylindrical storage tank are established. Through analytical analysis, the analytical expressions of the solutions of this kind of system are obtained. With different parameters, the dynamical behaviors of the solutions are different from the trivial ones. To prevent system instability, two selection principles that the stiffness equations are positive-definite and the nonlinear terms of the system are not regenerative elements are given. Meanwhile, numerical simulations are also given, which confirm the analytical results.
文摘The water-filling algorithm enables an energy-efficient OFDM-based transmitter by maximizing the capacity of a frequency selective fading channel. However, this optimal strategy requires the perfect channel state information at the transmitter that is not realistic in wireless applications. In this paper, we propose opportunistic error correction to maximize the data rate of OFDM systems without this limit. The key point of this approach is to reduce the dynamic range of the channel by discarding a part of the channel in deep fading. Instead of decoding all the information from all the sub-channels, we only recover the data via the strong sub-channels. Just like the water-filling principle, we increase the data rate over the stronger sub-channels by sacrificing the weaker sub-channels. In such a case, the total data rate over a frequency selective fading channel can be increased. Correspondingly, the noise floor can be increased to achieve a certain data rate compared to the traditional coding scheme. This leads to an energy-efficient receiver. However, it is not clear whether this method has advantages over the joint coding scheme in the narrow-band wireless system (e.g. the channel with a low dynamic range), which will be investigated in this paper.
文摘Where hydraulic characteristics of ship lock filling and emptying system are concerned, there are much bigger differences between prototype and model experiments. Based on the results of the prototype experiments fur the Three Gorges Project （TGP）, experiments on the feedback model were conducted of the ship-lock filling and emptying system, by means of technologies of drag reduction, under similar conditions as the operation of the prototype project. The experimental results show that the difference of drag co efficient reached-44% hetween the prototype and the model for the filling and emptying system of the ship-lock No. 3 for TGP and the difference of discharge coefficient was ahout 33% between them. The technologies of drag reduction are more efficient in the simulation of a ship lock filling and emptying system in order to he consistent for discharge, water level, time average pressure and pulsating pressure between prototypes and models.
