http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Microstructure Evolution of Inconel 718 Alloy during Ring Rolling Process
Xing-lin Zhu,Dong Liu,Li-juan Xing,Yang Hu,Yan-hui Yang 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.6
Microstructure determines the comprehensive mechanical properties and service life of ring parts. In this study, ring rolling process is considered as a multi-pass process which is parted into four phases, and the microstructure evolution model is then established based on the characteristics of this multi-pass process by combining with a 3D coupled thermo-mechanical FE model. By contrasting with experiment results, the microstructure evolution model is actually proven can be competently applied to predict the microstructure of the formed ring. Also through comprehensive analysis on distribution of recrystallization fractions based on the microstructure evolution model, conclusions can be summarized as following. (1) It is inaccurate to predict the microstructure by regarding the ring rolling as a single-pass deformation. The ring rolling process should be parted into different phases, and for each phase, the singlepass microstructure evolution model is adapted. (2) Different with single-pass deformation, due to the high temperature dwelling phase during ring rolling process, meta-dynamic recrystallization (MDR) is another important grain refinement mechanism besides dynamic recrystallization (DR). (3) MDR has different distribution trends with DR, which is benefit not only for grains refinement but also for microstructure uniformity. (4) Rolling penetration is obviously improved with feed rate increases, whereas, unduly high feed rate leads to recrystallization fraction decrease in outer layer area, which is adverse to microstructure uniformity.
Leader-Follower Consensus for a Class of Nonlinear Multi-Agent Systems
Xing-Hu Wang,Hai-Bo Ji 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.1
This paper deals with the leader-follower consensus problem for a class of nonlinear multi-agent sys-tems. All agents have identical nonlinear dynamics in the strict feedback form with Lipschitz growth condition. Both full state consensus protocol and dynamic output consensus protocol are provided. It is shown that under a connected undirected information communication topology, the proposed protocols can solve the leader-follower consensus problem. Two consensus protocol design procedures are presented and a numerical example is given to illustrate the proposed protocols.
Hu, Dong,Ran, Yu-Liang,Zhong, Xing,Hu, Hai,Yu, Long,Lou, Jin-Ning,Sun, Li-Xing,Yang, Zhi-Hua Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.6
Proteins that are unfolded or misfolded in the endoplasmic reticulum (ER) must be targeted for refolding or degradation to maintain the homeostasis of the ER. Derlin-1 was reportedly implicated in the retro-translocation of misfolded proteins from the ER to the cytosol for degradation. In this report, we showed that Derlin-1 was down-regulated in the endothelial cells derived from human hepatic cavernous hemangioma (CHEC) compared with other tested cells. Electron microscopy analysis showed that ER was aberrantly enlarged in CHEC cells, but not in other tested cells. When overexpressed, Derlin-1 induced the dilated ER to return normal size. This ER dynamic was associated with the activation of unfolded protein response (UPR). In CHEC cells where Derlin-1 was down-regulated, increased expression of the immunoglobulin heavy chain-binding protein (Bip) and UPR-specific splicing of X-box DNA-binding protein 1 (XBP1) mRNA were detected, as compared with that in other tested cells, indicating that UPR was activated. After Derlin-1 overexpression, the extent of UPR activation diminished, as evidenced by decreased expression of Bip, reduced amount of the spliced form of XBP1 ($XBP1_S$), and elevated expression of the unspliced form of XBP1 ($XBP1_U$). Taken together, these findings provide another example of a single protein being able to affect ER dynamic in mammalian cells, and an insight into the possible molecular mechanism(s).
( Xing Yu Li ),( Zi Chao Mao ),( Yue Hu Wang ),( Yi Xing Wu ),( Yue Qiu He ),( Chun Lin Long ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.3
Bacillus subtilis XF-1, a strain with demonstrated ability to control clubroot disease caused by Plasmodiophora brassicae, was studied to elucidate its mechanism of antifungal activity against P. brassicae. Fengycin-type cyclopeptides (FTCPs), a well-known class of compounds with strong fungitoxic activity, were purified by acid precipitation, methanol extraction, and chromatographic separation. Eight homologs of fengycin, seven homologs of dehydroxyfengycin, and six unknown FTCPs were characterized with LC/ESI-MS, LC/ESI-MS/MS, and NMR. FTCPs (250μg/ml) were used to treat the resting spores of P. brassicae (107/ml) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be cleaved by the FTCPs of B. subtilis XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol.
Hu, Wen-Xing,Kim, Byoung-Jo,Kwak, Younghwan,Seo, Eun-Young,Kim, Jung-Kyu,Han, Jae-Yeong,Kim, Ik-Hyun,Lim, Yong Pyo,Cho, In-Sook,Domier, Leslie L,Hammond, John,Lim, Hyoun-Sub The Korean Society of Plant Pathology 2019 Plant Pathology Journal Vol.35 No.4
For several years, temperatures in the Korean peninsula have gradually increased due to climate change, resulting in a changing environment for growth of crops and vegetables. An associated consequence is that emerging species of insect vector have caused increased viral transmission. In Jeju Island, Korea, occurrences of viral disease have increased. Here, we report characterization of five newly collected turnip mosaic virus (TuMV) isolates named KBJ1, KBJ2, KBJ3, KBJ4 and KBJ5 from a survey on Jeju Island in 2017. Full-length cDNAs of each isolate were cloned into the pJY vector downstream of cauliflower mosaic virus 35S and bacteriophage T7 RNA polymerase promoters. Their fulllength sequences share 98.9-99.9% nucleotide sequence identity and were most closely related to previously reported Korean TuMV isolates. All isolates belonged to the BR group and infected both Chinese cabbage and radish. Four isolates induced very mild symptoms in Nicotiana benthamiana but KBJ5 induced a hypersensitive response. Symptom differences may result from three amino acid differences uniquely present in KBJ5; Gly(382)Asp, Ile(891)Val, and Lys(2522)Glu in P1, P3, and NIb, respectively.
Hu, Xing,Zhang, Jianzhong,Deng, Fujin,Chen, Gui,Chen, Qiang,Din, Zaki ud The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.5
Circulating current exists among phases or between the DC link and the three phases in a modular multilevel converter (MMC). Suppression control of the alternating components in circulating current is a critical issue for the stable and efficient operation of an MMC. Due to the redundancy and symmetry of MMCs, some of the self-redundant states of MMCs can be used to suppress the alternating components in circulating current without affecting the output performance of the converter. In this paper, a theoretical derivation of the boundary of redundant states is given. Then a suppression strategy for circulating current is proposed based on prediction control and the boundary of redundant states. The selection range of the redundant states is narrowed in this case, which reduces the computation burden when compared to the original method and ensures excellent performance in the suppression of circulating current. Simulations and experiments are carried out to verify the effectiveness of the proposed strategy.
( Xing Hu ),( Linhua Ma ),( Shaocheng Huang ),( Jinke Huang ),( Kangning Sun ),( Tianyu Huang ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.8
In high diversity node situation, single-channel MAC protocols suffer from many collisions. To solve this problem, the research of multichannel MAC protocol has become a hotspot. And the cyclic quorum-based multichannel (CQM) MAC protocol outperformed others owing to its high frequency utilization. In addition, it can avoid the bottleneck that others suffered from and can be easily realized with only one transceiver. To obtain the accurate performance of CQM MAC protocol, a Markov chain model, which combines the channel hopping strategy of CQM protocol and IEEE 802.11 distributed coordination function (DCF), is proposed. The metrics (throughput and average packet transmission delay) are calculated in performance analysis, with respect to node number, packet rate, channel slot length and channel number. The results of numerical analysis show that the optimal performance of CQM protocol can be obtained in saturation bound situation. And then we obtain the saturation bound of CQM system by bird swarm algorithm (BSA). Finally, the Markov chain model and saturation bound are verified by Qualnet platform. And the simulation results show that the analytic and simulation results match very well.
“Reinhabitation” and the Urban Ecology of Gary Snyder
Hu Xing,Gi Taek Ryoo 한국영미어문학회 2021 영미어문학 Vol.- No.140
In his ecological writing, Gary Snyder has been committed to exploring urban space as a natural place to reinhabit. By reexamining the value and significance of urban nature, Snyder explores the complex and intimate connection between the urban space where humans participate in social activities and the natural environment that surrounds them. Drawing upon some key insights of urban ecology, this paper examines Snyder’s ecological visions exhibited in his poems and essays, with a particular thematic emphasis on the ecological network and ecological practice. Snyder recognizes that the structure of urban space is an ecological network in motion and emphasizes that the key to urban ecological practice is to recognize the local wild “information and experience” (PW 39). This paper will explore how Snyder reclaims the urban space as an ecological space while discarding the old dichotomy of city and nature, as well as how he finally achieves “reinhabitation” through ecological practices.