The snow enhancement experiments, carried out by injecting AgI and water vapor into orographically enhanced clouds (fog), have been conducted to confirm Li and Pitter's forced condensation process in a natural situ...The snow enhancement experiments, carried out by injecting AgI and water vapor into orographically enhanced clouds (fog), have been conducted to confirm Li and Pitter's forced condensation process in a natural situation. Nine ground-based experiments have been conducted at Daegwallyeong in the Taebaek Mountains for the easterly foggy days from January-February 2006. We then obtained the optimized conditions for the Daegwallyeong region as follows: the small seeding rate (1.04 g min-1) of AgI for the easterly cold fog with the high humidity of Gangneung. Additional experiments are needed to statistically estimate the snowfall increment caused by the small AgI seeding into the orographical fog (cloud) over the Taeback Mountains.展开更多
The paper introduces thermal buoyancy effects to experimental investigation of wind tunnel simulation on direct air-cooled condenser for a large power plant. In order to get thermal flow field of air-cooled tower, PIV...The paper introduces thermal buoyancy effects to experimental investigation of wind tunnel simulation on direct air-cooled condenser for a large power plant. In order to get thermal flow field of air-cooled tower, PIV experiments are carried out and recirculation ratio of each condition is calculated. Results show that the thermal flow field of the cooling tower has great influence on the recirculation under the cooling tower. Ameliorating the thermal flow field of the cooling tower can reduce the recirculation under the cooling tower and improve the efficiency of air-cooled condenser also.展开更多
Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology i...Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology is a notoriously complex task for several reasons:software is complex,a large number of nodes are involved,the network is non-ideal,etc.Developers usually adopt small virtual laboratories or costly real devnets based on real software.Researchers usually prefer simulations of a large number of nodes based on simplified models.In this paper,we aim to obtain the advantages of both approaches,i.e.,performing large,realistic,inexpensive,and flexible experiments,using real blockchain software within a virtual environment.To do that,we address the challenge of running large blockchain networks in a single physical machine,leveraging Linux and Docker.We analyze a number of problems that arise when large blockchain networks are emulated,and we provide technical solutions for all of them.Finally,we describe two experiences of emulating fairly large blockchain networks on a single machine:adopting both research-oriented and production-oriented software and involving more than 3000 containers.展开更多
A numerical experiment of squall-line formation has been made with a baroclinic quasi-two-dimensional PE-model.The results show that the latent heat released by cumulus convection plays an important role in the format...A numerical experiment of squall-line formation has been made with a baroclinic quasi-two-dimensional PE-model.The results show that the latent heat released by cumulus convection plays an important role in the formation of a certain kind of squall-line.In the process of the formation of squall-line,the nonlinear concentra- tion of perturbation is clearly shown.展开更多
In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC). The particle image velocimetery (PIV) experiments were carried out to get the...In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC). The particle image velocimetery (PIV) experiments were carried out to get thermal flow field of a ACC under different conditions in low velocity wind tunnel,at the same time,the recirculation ratio at cooling tower was measured,so the relationship between flow field characteristics and recirculation ratio of cooling tower can be discussed. From the results we can see that the flow field configuration around cooling tower has great effects on average recirculation ratio under cooling tower. The eddy formed around cooling tower is a key reason that recirculation produces. The eddy intensity relates to velocity magnitude and direction angle,and the configuration of eddy lies on the geometry size of cooling tower. So changing the flow field configuration around cooling tower reasonably can decrease recirculation ratio under cooling tower,and heat dispel effect of ACC can also be improved.展开更多
基金supported by the Korea Science and Engineering Foundation (KOSEF)grant funded by the Korea government (MOST) R01-2006-000-10470-0 and R01-2006-000-11233-0 from the Basic Research Program of the Korea Science & Engineering Foundationby "Maintenance and Research of Cloud Phys-ical Observation System" and "Research for the Meteo-rological Observation Technology and its Application" ofMETRI, KMA project.
文摘The snow enhancement experiments, carried out by injecting AgI and water vapor into orographically enhanced clouds (fog), have been conducted to confirm Li and Pitter's forced condensation process in a natural situation. Nine ground-based experiments have been conducted at Daegwallyeong in the Taebaek Mountains for the easterly foggy days from January-February 2006. We then obtained the optimized conditions for the Daegwallyeong region as follows: the small seeding rate (1.04 g min-1) of AgI for the easterly cold fog with the high humidity of Gangneung. Additional experiments are needed to statistically estimate the snowfall increment caused by the small AgI seeding into the orographical fog (cloud) over the Taeback Mountains.
文摘The paper introduces thermal buoyancy effects to experimental investigation of wind tunnel simulation on direct air-cooled condenser for a large power plant. In order to get thermal flow field of air-cooled tower, PIV experiments are carried out and recirculation ratio of each condition is calculated. Results show that the thermal flow field of the cooling tower has great influence on the recirculation under the cooling tower. Ameliorating the thermal flow field of the cooling tower can reduce the recirculation under the cooling tower and improve the efficiency of air-cooled condenser also.
基金supported by project SERICS(PE00000014)under the MUR National Recovery and Resilience Plan funded by the European Union-NextGenerationEU.
文摘Blockchain,like any other complex technology,needs a strong testing methodology to support its evolution in both research and development contexts.Setting up meaningful tests for permissionless blockchain technology is a notoriously complex task for several reasons:software is complex,a large number of nodes are involved,the network is non-ideal,etc.Developers usually adopt small virtual laboratories or costly real devnets based on real software.Researchers usually prefer simulations of a large number of nodes based on simplified models.In this paper,we aim to obtain the advantages of both approaches,i.e.,performing large,realistic,inexpensive,and flexible experiments,using real blockchain software within a virtual environment.To do that,we address the challenge of running large blockchain networks in a single physical machine,leveraging Linux and Docker.We analyze a number of problems that arise when large blockchain networks are emulated,and we provide technical solutions for all of them.Finally,we describe two experiences of emulating fairly large blockchain networks on a single machine:adopting both research-oriented and production-oriented software and involving more than 3000 containers.
文摘A numerical experiment of squall-line formation has been made with a baroclinic quasi-two-dimensional PE-model.The results show that the latent heat released by cumulus convection plays an important role in the formation of a certain kind of squall-line.In the process of the formation of squall-line,the nonlinear concentra- tion of perturbation is clearly shown.
文摘In order to get thermal flow field of direct air-cooled system,the hot water was supplied to the model of direct air-cooled condenser(ACC). The particle image velocimetery (PIV) experiments were carried out to get thermal flow field of a ACC under different conditions in low velocity wind tunnel,at the same time,the recirculation ratio at cooling tower was measured,so the relationship between flow field characteristics and recirculation ratio of cooling tower can be discussed. From the results we can see that the flow field configuration around cooling tower has great effects on average recirculation ratio under cooling tower. The eddy formed around cooling tower is a key reason that recirculation produces. The eddy intensity relates to velocity magnitude and direction angle,and the configuration of eddy lies on the geometry size of cooling tower. So changing the flow field configuration around cooling tower reasonably can decrease recirculation ratio under cooling tower,and heat dispel effect of ACC can also be improved.