The vapor-liquid self-adjusting controller is an innovative automatic regulating valve.In order to ensure adjusted objects run safely and economically,the controller automatically adjusts the liquid flux to keep liqui...The vapor-liquid self-adjusting controller is an innovative automatic regulating valve.In order to ensure adjusted objects run safely and economically,the controller automatically adjusts the liquid flux to keep liquid level at a required level according to physical properties of vapor-liquid two-phase fluid.The adjusting mechanics,the controller’s performance and influencing factors of its stability have been analyzed in this paper.The theoretical analysis and successful applications have demonstrated this controller can keep the liquid level steady with good performance.The actual application in industry has shown that the controller can satisfactorily meet the requirement of industrial production and has wide application areas.展开更多
Network measurement is an important approach to understand network behaviors, which has been widely studied. Both Transfer Control Protocol （TCP） and Interact Control Messages Protocol （ICMP） are applied in networ...Network measurement is an important approach to understand network behaviors, which has been widely studied. Both Transfer Control Protocol （TCP） and Interact Control Messages Protocol （ICMP） are applied in network measurement, while investigating the differences between the measured results of these two protocols is an important topic that has been less investigated. In this paper, to compare the differences between TCP and ICMP when they are used in measuring host connectivity, RTT, and packet loss rate, two groups of comparison programs have been designed, and after careful evaluation of the program parameters, a lot of comparison experiments are executed on the Internet. The experimental results show that, there are significant differences between the host connectivity measured using TCP or ICMP; in general, the accuracy of connectivity measured using TCP is 20%- 30% higher than that measured using ICMP. The case of RTT and packet loss rate is complicated, which are related to path loads and destination host loads. While commonly, the RTF and packet loss rate＂ measured using TCP or ICMP are very close. According to the experimental results, some advices are also given on protocol selection for conducting accurate connectivity, RTF and packet loss rate measurements.展开更多
In order to study whether the intemal control of enterprises is effective, this paper studies the relationship between the quality of internal control and the performance of the company in 2012-2015, in which 61 liste...In order to study whether the intemal control of enterprises is effective, this paper studies the relationship between the quality of internal control and the performance of the company in 2012-2015, in which 61 listed companies in China＇s Shanghai traffic transportation industry are studied. The results show that the quality of internal control has a significant positive correlation with the financial performance of enterprises. In particular, the internal control is significantly correlated with the company＇s growth ability, and the internal control is positively correlated with the profitability of the company. This research provides empirical data and decision-making basis for the state to deepen the construction of internal control system and strengthen internal control management of enterprises.展开更多
The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulenc...The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.展开更多
文摘The vapor-liquid self-adjusting controller is an innovative automatic regulating valve.In order to ensure adjusted objects run safely and economically,the controller automatically adjusts the liquid flux to keep liquid level at a required level according to physical properties of vapor-liquid two-phase fluid.The adjusting mechanics,the controller’s performance and influencing factors of its stability have been analyzed in this paper.The theoretical analysis and successful applications have demonstrated this controller can keep the liquid level steady with good performance.The actual application in industry has shown that the controller can satisfactorily meet the requirement of industrial production and has wide application areas.
基金This work was financially supported by National Natural Science Foundation of China under grant60273070and60403031,and theNational high-Technology (863) Programunder grant2005AA121560
文摘Network measurement is an important approach to understand network behaviors, which has been widely studied. Both Transfer Control Protocol （TCP） and Interact Control Messages Protocol （ICMP） are applied in network measurement, while investigating the differences between the measured results of these two protocols is an important topic that has been less investigated. In this paper, to compare the differences between TCP and ICMP when they are used in measuring host connectivity, RTT, and packet loss rate, two groups of comparison programs have been designed, and after careful evaluation of the program parameters, a lot of comparison experiments are executed on the Internet. The experimental results show that, there are significant differences between the host connectivity measured using TCP or ICMP; in general, the accuracy of connectivity measured using TCP is 20%- 30% higher than that measured using ICMP. The case of RTT and packet loss rate is complicated, which are related to path loads and destination host loads. While commonly, the RTF and packet loss rate＂ measured using TCP or ICMP are very close. According to the experimental results, some advices are also given on protocol selection for conducting accurate connectivity, RTF and packet loss rate measurements.
文摘In order to study whether the intemal control of enterprises is effective, this paper studies the relationship between the quality of internal control and the performance of the company in 2012-2015, in which 61 listed companies in China＇s Shanghai traffic transportation industry are studied. The results show that the quality of internal control has a significant positive correlation with the financial performance of enterprises. In particular, the internal control is significantly correlated with the company＇s growth ability, and the internal control is positively correlated with the profitability of the company. This research provides empirical data and decision-making basis for the state to deepen the construction of internal control system and strengthen internal control management of enterprises.
基金supported by Hatakeyama Grant-in-Aid(2014)of Turbomachinery of Japanthe support of Dr.Hikaru Matsumiya and Dr.Tetsuya Kogaki(National Institute of Advanced Industrial Science and Technology of Japan)for providing MEL blade data
文摘The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.
