266 research outputs found
Comparison of cavitation erosion rate with liquid impingement erosion rate.
Both cavitation erosion and liquid impingement erosion are phenomena that can cause pipe wall thinning in power plants. The Code for Power Generation Facilities, Rules on Pipe Wall Thinning Management, was published by the JSME (Japan Society of Mechanical Engineers) in 2005. The code says that cavitation erosion shall be prevented either in the design stage or by daily inspection. On the other hand, liquid impingement erosion can occur in any location where a working fluid attacks a pipe wall at high flow velocities. Therefore, it is very important to evaluate the amount of erosion by liquid impingement for pipe steels quantitatively from the viewpoint of aging management. In this study, we carried out both cavitation erosion and liquid impingement erosion tests, and clarified the relation between the two erosion rates. As a result, we found that the erosion rate by cavitation increases in proportion with the 5.2th to 6.8th power of the flow velocity and that by liquid impingement with the 6.0th to 7.4th power. Moreover, a good correlation was obtained between erosion rates by cavitation and by liquid impingement. We also discussed the erosion mechanism with SEM photography, and proposed an erosion model.http://deepblue.lib.umich.edu/bitstream/2027.42/84233/1/CAV2009-final32.pd
Feminized Asians and Masculinized Blacks: The Construction of Gendered Races in the United States
This study attempts to clarify how race and gender are both socially constructed categories, and mutually constituted in ways that promote White, heterosexual, patriarchal standards of masculinity and femininity. I argue throughout this paper that Black women are deemed less marriageable due in part to the fact that they have been masculinized throughout the history of the United States. Similarly, Asian men are deemed less marriageable due in part to the fact they have been feminized throughout the history of the United States. Through my research I hope to clarify the role that certain historical events played in the dual gendering of Asians as feminine and Blacks as masculine. I will also examine more contemporary media influences such as film and music, which continue to gender and marginalize Asian and Black bodies by perpetuating old myths and stereotypes today
Visualization of heat and stress flows in thermodynamic crystals fabricated by laser scanning stereolithography
Students’ Perception of Different Forms of English Lessons: Food for Thought on a “New” Learning Style in the Post-COVID Era
Millimeter-wave Evolution for 5G Cellular Networks
Triggered by the explosion of mobile traffic, 5G (5th Generation) cellular
network requires evolution to increase the system rate 1000 times higher than
the current systems in 10 years. Motivated by this common problem, there are
several studies to integrate mm-wave access into current cellular networks as
multi-band heterogeneous networks to exploit the ultra-wideband aspect of the
mm-wave band. The authors of this paper have proposed comprehensive
architecture of cellular networks with mm-wave access, where mm-wave small cell
basestations and a conventional macro basestation are connected to
Centralized-RAN (C-RAN) to effectively operate the system by enabling power
efficient seamless handover as well as centralized resource control including
dynamic cell structuring to match the limited coverage of mm-wave access with
high traffic user locations via user-plane/control-plane splitting. In this
paper, to prove the effectiveness of the proposed 5G cellular networks with
mm-wave access, system level simulation is conducted by introducing an expected
future traffic model, a measurement based mm-wave propagation model, and a
centralized cell association algorithm by exploiting the C-RAN architecture.
The numerical results show the effectiveness of the proposed network to realize
1000 times higher system rate than the current network in 10 years which is not
achieved by the small cells using commonly considered 3.5 GHz band.
Furthermore, the paper also gives latest status of mm-wave devices and
regulations to show the feasibility of using mm-wave in the 5G systems.Comment: 17 pages, 12 figures, accepted to be published in IEICE Transactions
on Communications. (Mar. 2015
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