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Numerical simulations of FPSO with sloshing tanks in a random freak waves

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Journal of Hydrodynamics 2022年第3期34卷 491-498页

作者： Yuan Zhuang Guo Wang De-cheng Wan jian-wei wu Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Marine Design and Research Institute of China Shanghai200011China wuhan Second Ship Design and Research Institute Wuhan430205China

This paper presents a potential-viscous coupled method to simulate a floating production storage and offloading(FPSO)with two liquefied natural gas(LNG)sloshing tanks in a random freak *** potential theory uses high-order-spectral(HOS)*** random wave is generated by HOS for 2000 s,and a freak wave is observed around 1830 *** FPSO LNG model was firstly verified in regular waves using HOS-computational fluid dynamics(CFD)coupled method and validated the HOS-CFD coupled method can solve the ship motion coupled with sloshing tanks *** FPSO with LNG tanks are then simulated in the freak wave,showed the coupling effects when the freak wave *** the existence of the sloshing tanks,the amplitude of the roll motion decreases and the period of roll motion *** breaking phenomenon can be observed when the wave crest of the freak wave encounters with the ship.

关键词： Ship motion with sloshing tank high-order-spectral-computational fluid dynamics(HOS-CFD)method naoe-FOAM-SJTU solver freak waves

Preliminary control of the air entrainment in bow wave based on the Liutex force method

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Journal of Hydrodynamics 2022年第3期34卷 483-490页

作者： Yi-ding Hu jian-wei wu De-cheng Wan Guo Wang Yi-qian Wang Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China wuhan Second Ship Design and Research Institute Wuhan430205China Marine Design and Research Institute of China Shanghai200011China School of Mathematical Science Soochow UniversitySuzhou215006China

Trails induced by air entrainment of bow wave breaking can be observed clearly around an advancing ship,making it prong to be detected and causing reduction in hydrodynamic *** breaking bow wave region,different scale of coherent vortex structures related closely to the air entrainment are *** formation and evolution of bubble clouds can be accounted partly by the swirling vortex flow of the jet *** this work,high-fidelity simulation of the bow wave breaking around a rectangular thin plate is performed with the in-house code BAMR-SJTU.A Liutex force model is constructed to investigate the interaction between the free surface and vortices,and to explore the possibility of alleviating or controlling the air *** study is the first attempt to manipulate vortices corresponding to the air entrainment of the bow wave *** typical vortex structures based on the Liutex vortex identification method and the distribution of the vortex force are *** of the vortex structures and the entrapped bubbles is conducted to illustrate the efficiency of Liutex force model in air entrainment control.

关键词： Bow wave breaking air entrainment coherent vortex structures Liutex force field model

Microstructure,Properties and Heat Treatment Process of Powder Metallurgy Superalloy FGH95

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Journal of Iron and Steel Research International 2006年第5期13卷 65-68页

作者： GUO wei-min wu jian-tao ZHANG Feng-ge ZHAO Ming-han High Temperature Materials Research Institute Central Iron and Steel Research Institute Beijing 100081 China

Microstructure and properties of nickel based powder metallurgy （PM） superalloy were presented. Effects of nonmetallic inclusions and heat treatment on microstructure and properties were. discussed. Development tend... 详细信息

关键词： microstructure property PM superalloy heat treatment

Estimating index of population trend by re-sampling techniques （jackknife and bootstrap） and its application to the life table study of rice leaf roller, Cnaphalocrocis medinalis （Lepidoptera： Pyralidae）

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Insect Science 2008年第2期15卷 153-161页

作者： Fang-Ling Tao Shi-Fan Min wei-jian wu Guang-Wen Liang Ling Zeng Laboratory of Insect Ecology South China Agriculture University Guangzhou Department of Food Science Jiangxi AgriculturalUniversity Nanchang China

Taking a published natural population life table of rice leaf roller, Cnaphalocrocis medinalis （Lepidoptera： Pyralidae）, as an example, we estimated the population trend index, I, via re-sampling methods （jackknife and bootstrap）, determined its statistical properties and illustrated the application of these methods in determining the control effectiveness of bio- agents and chemical insecticides. Depending on the simulation outputs, the smoothed distribution pattern of the estimates of I by delete-1 jackknife is visually distinguishable from the normal density, but the smoothed pattern produced by delete-d jackknife, and logarithm- transformed smoothed patterns produced by both empirical and parametric bootstraps, matched well the corresponding normal density. Thus, the estimates of I produced by delete-1 jackknife were not used to determine the suppressive effect of wasps and insecticides. The 95% percent confidence intervals or the narrowest 95 percentiles and Z-test criterion were employed to compare the effectiveness of Trichogrammajaponicum Ashmead and insecticides （powder, 1.5% mevinphos ＋ 3% alpha-hexachloro cyclohexane） against the rice leaf roller based on the estimates of I produced by delete-d jackknife and bootstrap techniques. At a = 0.05 level, there were statistical differences between wasp treatment and control, and between wasp and insecticide treatments, if the normality is ensured, or by the narrowest 95 percentiles. However, there is still no difference between insecticide treatment and control. By Z-test criterion, wasp treatment is better than control and insecticide treatment with P-value 〈 0.01. Insecticide treatment is similar to control with P-value 〉 0.2 indicating that 95% confidence intervals procedure is more conservative. Although similar conclusions may be drawn by re-sampling techniques, such as the delta method, about the suppressive effect of trichogramma and insecticides, the normality of the estimates can be checked and guarante

关键词： index of population trend life table re-sampling (jackknife bootstrap) riceleaf roller ( Cnaphalocrocis medinalis)

Analysis on degradation mechanisms of normally-off p-GaN gate AlGaN/GaN high-electron mobility transistor

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Chinese Physics B 2021年第4期30卷 448-452页

作者： Si-De Song Su-Zhen wu Guo-Zhu Liu wei Zhao Yin-Quan Wang jian-wei wu Qi He The 58th Institution of Electronic Science and Technology Group Corporation of China Wuxi 214000China

The degradation mechanisms of enhancement-mode p-GaN gate AlGaN/GaN high-electron mobility transistor was analyzed extensively,by means of drain voltage stress and gate bias *** results indicate that:(ⅰ) High constant drain voltage stress has only a negligible impact on the device electrical parameters,with a slightly first increase and then decrease in output current;(ⅱ) A negative shift of threshold voltage and increased output current were observed in the device subjected to forward gate bias stress,which is mainly ascribed to the hole-trapping induced by high electric field across the p-GaN/AlGaN interface;(ⅲ) The analyzed device showed an excellent behavior at reverse gate bias stress,with almost unaltered threshold voltage,output current,and gate leakage current,exhibiting a large gate swing in the negative *** results are meaningful and valuable in directing the process optimization towards a high voltage and high reliable enhanced AlGaN/GaN high-electron mobility transistor.

关键词： high-electron-mobility transistors(HEMTs) stress degradation threshold voltage

Optimization of hepatobiliary phase delay time of Gd-EOB-DTPA-enhanced magnetic resonance imaging for identification of hepatocellular carcinoma in patients with cirrhosis of different degrees of severity

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World Journal of Gastroenterology 2018年第3期24卷 415-423页

作者： jian-wei wu Yue-Cheng Yu Xian-Li Qu Yan Zhang Hong Gao Department of Radiology Bayi HospitalNanjing University of Chinese Medicine Liver Disease Center Bayi HospitalNanjing University of Chinese Medicine

AIM To optimize the hepatobiliary phase delay time(HBPDT) of Gd-EOB-DTPA-enhanced magnetic resonance imaging(GED-MRI) for more efficient identification of hepatocellular carcinoma(HCC) occurring in different degrees of cirrhosis assessed by Child-Pugh(CP) *** The liver parenchyma signal intensity(LPSI), the liver parenchyma(LP)/HCC signal ratios, and the visibility of HCC at HBP-DT of 5, 10, 15, 20, and 25 min(i.e., DT-5, DT-10, DT-15, DT-20, and DT-25) after injection of GdEOB-DTPA were collected and analyzed in 73 patients with cirrhosis of different degrees of severity(including 42 patients suffering from HCC) and 18 healthy adult *** The LPSI increased with HBP-DT more significantly in the healthy group than in the cirrhosis group(F = 17.361, P < 0.001). The LP/HCC signal ratios had a significant difference(F = 12.453, P < 0.001) among various HBP-DT points, as well as between CP-A and CP-B/C subgroups(F = 9.761, P < 0.001). The constituent ratios of HCC foci identified as obvious hypointensity(+++), moderate hypointensity(++), and mild hypointensity or isointensity(+/-) kept stable from DT-10 to DT-25: 90.6%, 9.4%, and 0.0% in the CP-A subgroup; 50.0%, 50.0%, and 0.0% in the CP-B subgroup; and 0.0%, 0.0%, and 100.0% in the CP-C subgroup, *** The severity of liver cirrhosis has significant negative influence on the HCC visualization by GED-MRI. DT-10 is more efficient and practical than other HBP-DT points to identify most of HCC foci emerging in CP-A cirrhosis, as well as in CP-B cirrhosis; but an HBP-DT of 15 min or longer seems more appropriate than DT-10 for visualization of HCC in patients with CP-C cirrhosis.

关键词： Magnetic resonance imaging Gd-EOBDTPA Hepatobiliary phase Delay time Hepatocellular carcinoma Cirrhosis Optimization

Synthesis of unnatural N-glycosyl α-amino acids via Petasis reaction

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Chinese Chemical Letters 2014年第4期25卷 532-534页

作者： Chuan-Zhou Tao Zhong-Tang Zhang jian-wei wu Rong-Hua Li Zhi-Ling Cao School of Chemical Engineering Huaihai Institute of Technology jiangsu Marine Resources Development Research Institute

A convenient and efficient protocol for the synthesis of unnatural N-glycosyl cz-amino acids was developed. Condensation of 1,3,4,6-tetra-O-actyl-/%D-glucosamine hydrochloride, alkenyl boronic acid, and glyoxylic acid was achieved in CH2C12 to give the derivatives of 2-（N-glycosyl）aminobut-3-enoic acid which may find applications in glycobiology research and medicinal chemistry.

关键词： N-'Glycosyl s-amino acid Petasis reaction D-Glucosamine Alkenyl boronic acid

Study of dynamic pressure roadway supporting scheme under condi- tion of thick composite roof

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 119-125页

作者： wei-Jun WANG Li-Qiang LUO wei-jian YU Hai wu Yan-Si QU Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and TechnologyXiangtan 411201 China

This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.

关键词： thick composite roof dynamic pressurized roadway high stress surrounding rock control

Combined effects of cycling endurance and total ionizing dose on floating gate memory cells

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Chinese Physics B 2022年第5期31卷 535-539页

作者： Si-De Song Guo-Zhu Liu Qi He Xiang Gu Gen-Shen Hong jian-wei wu The 58th Institution of Electronic Science and Technology Group Corporation of China Wuxi 214000China

The combined effects of cycling endurance and radiation on floating gate memory cell are investigated in detail,and the obtained results are listed below.(i)The programmed flash cells with a prior appropriate number of program and easing cycling stress exhibit much smaller threshold voltage shift than without those in response to radiation,which is ascribed mainly to the recombination of trapped electrons(introduced by cycling stress)and trapped holes(introduced by irradiation)in the oxide surrounding the floating gate.(ii)The radiation induced transconductance degradation in prior cycled flash cell is more severe than those without cycling stress in the programmed state or erased state.(iii)Radiation is more likely to set up the interface generation in programmed state than in erased *** paper will be useful in understanding the issues involved in cycling endurance and radiation effects as well as in designing radiation hardened floating gate memory cells.

关键词： radiation floating gate threshold voltage recombination