Simulation and assessment of gas dispersion above sea from a subsea release: A CFD-based approach

Xinhong Li,Guoming Chen,Renren Zhang,Hongwei Zhu,Changhang Xu 대한조선학회 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

This paper presents a comprehensive simulation and assessment of gas dispersion above sea from a subsea release using a Computational Fluid Dynamics (CFD) approach. A 3D CFD model is established to evaluate the behavior of flammable gas above sea, and a jack-up drilling platform is included to illustrate the effect of flammable gas cloud on surface vessels. The simulations include a matrix of scenarios for different surface release rates, distances between surface gas pool and offshore platform, and wind speeds. Based on the established model, the development process of flammable gas cloud above sea is predicted, and the dangerous area generated on offshore platform is assessed. Additionally, the effect of some critical factors on flammable gas dispersion behavior is analyzed. The simulations produce some useful outputs including the detailed parameters of flammable gas cloud and the dangerous area on offshore platform, which are expected to give an educational reference for conducting a prior risk assessment and contingency planning.

Thickness Uniformity Adjustment of Inkjet Printed Light-emitting Polymer Films

Xinhong Yu,Yanchun Han 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

SUNKEN HOLLOW CARBON SPHERES SUPPORTED Pt ELECTROCATALYST FOR EFFICIENT METHANOL OXIDATION AND OXYGEN REDUCTION REACTION

XINHONG ZHAO,PENG WANG,NAIFEI REN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.7

Sunken hollow carbon spheres (SHCs) are prepared by using glucose as carbon source andpolystyrene spheres (PSs) as templates. Pt particles are then loaded on the SHCs as electro-catalyst and used for catalyzing both methanol oxidation and oxygen reduction reaction (ORR)in acidic media. Physical measurements show that the SHCs are formed due to sinking of hollowcarbon spheres. It can be imagined that the SHCs have the similar speci¯c surface area ashollow carbon spheres with reduced volume. Moreover, the SHCs have high surface area(786 : 3 m 2 ・ g-1 ) with hollow and sunken structure are bene¯cial for the uniform dispersion ofthe noble metal particles and e±ciently improve the mass transfer in catalytic reactions. Thecyclic voltammogram measurements show that the current densities on Pt/SHC electrocatalystare 2.1 times (1284 mA ・ mg-1Pt) that on commercial Pt/C for methanol oxidation and 1.5 times(163 : 7 mA ・ mg-1Pt) that on Pt/C for ORR at the same Pt loadings, being promising candidatefor fuel cell electrocatalyst.

Simulation and assessment of gas dispersion above sea from a subsea release: A CFD-based approach

Li, Xinhong,Chen, Guoming,Zhang, Renren,Zhu, Hongwei,Xu, Changhang The Society of Naval Architects of Korea 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

This paper presents a comprehensive simulation and assessment of gas dispersion above sea from a subsea release using a Computational Fluid Dynamics (CFD) approach. A 3D CFD model is established to evaluate the behavior of flammable gas above sea, and a jack-up drilling platform is included to illustrate the effect of flammable gas cloud on surface vessels. The simulations include a matrix of scenarios for different surface release rates, distances between surface gas pool and offshore platform, and wind speeds. Based on the established model, the development process of flammable gas cloud above sea is predicted, and the dangerous area generated on offshore platform is assessed. Additionally, the effect of some critical factors on flammable gas dispersion behavior is analyzed. The simulations produce some useful outputs including the detailed parameters of flammable gas cloud and the dangerous area on offshore platform, which are expected to give an educational reference for conducting a prior risk assessment and contingency planning.

Gene Expression Profiling in the Pituitary Gland of Laying Period and Ceased Period Huoyan Geese

Luan, Xinhong,Cao, Zhongzan,Xu, Wen,Gao, Ming,Wang, Laiyou,Zhang, Shuwei Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.7

Huoyan goose is a Chinese local breed famous for its higher laying performance, but the problems of variety degeneration have emerged recently, especially a decrease in the number of eggs laid. In order to better understand the molecular mechanism that underlies egg laying in Huoyan geese, gene profiles in the pituitary gland of Huoyan geese taken during the laying period and ceased period were investigated using the suppression subtractive hybridization (SSH) method. Total RNA was extracted from pituitary glands of ceased period and laying period geese. The cDNA in the pituitary glands of ceased geese was subtracted from the cDNA in the pituitary glands of laying geese (forward subtraction); the reverse subtraction was also performed. After sequencing and annotation, a total of 30 and 24 up and down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These genes mostly related to biosynthetic process, cellular nitrogen compound metabolic process, transport, cell differentiation, cellular protein modification process, signal transduction, small molecule metabolic process. Furthermore, eleven genes were selected for further analyses by quantitative real-time PCR (qRT-PCR). The qRT-PCR results for the most part were consistent with the SSH results. Among these genes, Synaptotagmin-1 (SYT1) and Stathmin-2 (STMN2) were substantially over-expressed in laying period compared to ceased period. These results could serve as an important reference for elucidating the molecular mechanism of higher laying performance in Huoyan geese.

Sensorless Control Strategy of Permanent Magnet Synchronous Motor Based on Fuzzy Sliding Mode Controller and Fuzzy Sliding Mode Observer

Zou Xinhong,Ding Hongchang,Li Jinhong 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

This paper proposes a permanent magnet synchronous motor sensorless control strategy based on fuzzy sliding mode controller and fuzzy sliding mode observer. In order to improve the response speed of the system and the anti-interference ability of the system, a sliding mode controller (SMC) is used to replace the PI regulator in the speed loop. In order to suppress the chattering caused by sliding mode variable structure control and reduce the error caused by chattering, the SMC and sliding mode observer (SMO) are improved. An integral sliding mode surface is used in the SMC, and a continuous saturation function is used instead of a discontinuous sign function. The square of the speed error is introduced in the switch term of the exponential approaching law to improve the dynamic quality of approaching motion. The switching function in the SMO also uses a saturation function to suppress chattering caused by switching. Fuzzy rules are established to adaptively adjust the switching gain of the SMO and the parameters in the SMC’s reaching law, which further improves the performance of the control system. Simulations and experiments prove that the proposed control strategy has the characteristics of small chattering, fast response speed, and strong robustness.

중국 숫자보에 관한 담론 연구

한신홍 ( Han Xinhong ),손민정 ( Minjung Son ) 세계음악학회 2019 음악과 문화 Vol.0 No.41

The purpose of this study is to analyze the social, cultural, and educational meanings of the Chinese numbered musical notation by analyzing the Chinese modern academic papers on its uses. Numbered musical notation originated in Europe was introduced to China at the end of the 19th century through musical culture exchange, gradually changing according to the regional characteristics of China, and ended up with the present Chinese numbered notation. The current numbered notation has become a systematic system in the field of public education such as basic music education and popular music in China. The research method applied in this study is to translate academic papers related to Chinese scholarship from 1951 to 2018 into Korean and then use the qualitative research software < Nvivo12 > to interpret the multi-layered determinants involved in the discourse. Through this study, it can be seen that the discourse of the academic community about numbered notation has changed with the changes of Chinese music education and education policy since the foundation of the country, also having cultural policy and international relations of the Chinese government.

Formal Analysis of Automatic Train Protection and Block System for Regional Line Using VDM++

Guo Xie,Xinhong Hei,Hiroshi Mochizuki,Sei Takahashi,Hideo Nakamura 한국철도학회 2012 International Journal of Railway Vol.5 No.2

This paper introduced a novel railway system, Automatic Train Protection and Block (ATPB) briefly, which is proposed to improve the efficiency of existing regional train lines with low cost in Japan. The biggest superiority of ATPB system is a great use of universal and mature technologies, such as GPS and regular mobile telephone networks, so that there is nearly no increment of trackside equipments in the reconstruction. Then in order to guarantee the system safety, a formal model of ATPB is established and analyzed by formal method VDM++. Firstly, the specification is specified by VDM++ formally without ambiguity. Secondly, its internal consistency is proved by discharging the proof obligations. And finally, its satisfiability is checked by systematic testing, which executes specification and checks the outputs against corresponding inputs.

A soybean plastidic ATP/ADP transporter gene, GmAATP, is involved in carbohydrate metabolism in transgenic Arabidopsis

Feibing Wang,Xinhong Chen,Fan Zhang,Yuan Niu,Yuxiu Ye,Sitong Qi,Qing Zhou 한국식물생명공학회 2017 Plant biotechnology reports Vol.11 No.3

The plastidic ATP/ADP transporter (AATP) imports adenosine triphosphate (ATP) from the cytosol into plastids, resulting in the increase of the ATP supply to facilitate anabolic synthesis in heterotrophic plastids of dicotyledonous plants. The regulatory role of GmAATP from soybean in increasing starch accumulation has not been investigated. In this study, a gene encoding the AATP protein, named GmAATP, was successfully isolated from soybean. Transient expression of GmAATP in Arabidopsis protoplasts and Nicotiana benthamiana leaf epidermal cells revealed the plastidic localization of GmAATP. Its expression was induced by exogenous sucrose treatment in soybean. The coding region of GmAATP was cloned into a binary vector under the control of 35S promoter and then transformed into Arabidopsis to obtain transgenic plants. Constitutive expression of GmAATP significantly increased the sucrose and starch accumulation in the transgenic plants. Real-time quantitative PCR (qRT-PCR) analysis showed that constitutive expression of GmAATP up-regulated the expression of phosphoglucomutase (AtPGM), ADP-glucose pyrophosphorylase (AGPase) small subunit (AtAGPase-S1 and AtAGPase-S2), AGPase large subunit (AtAGPase-L1 and AtAGPase-L2), granule-bound starch synthase (AtGBSS I and AtGBSS II), soluble starch synthases (AtSSS I, AtSSS II, AtSSS III, and AtSSS IV), and starch branching enzyme (AtSBE I and AtSBE II) genes involved in starch biosynthesis in the transgenic Arabidopsis plants. Meanwhile, enzymatic analyses indicated that the major enzymes (AGPase, GBSS, SSS, and SBE) involved in the starch biosynthesis exhibited higher activities in the transgenic plants compared to the wild type (WT). These findings suggest that GmAATP may improve starch content of Arabidopsis by up-regulating the expression of the related genes and increasing the activities of the major enzymes involved in starch biosynthesis. All these results suggest that GmAATP could be used as a candidate gene for developing high starch-accumulating plants as alternative energy crops.

Power Flow Management in Hybrid Electric Vehicles

C. Purushothama,Xinhong Chen,Le Duc Chien,Jae Ou Chae,Bong Soo Kim 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Hybrid electrical vehicles are very popular due to their extended operating range, reduced emission, improved fuel economy and rapid refueling. They are powered by an internal combustion engine and an electrical motor which driven by a battery. Battery is charged either by the engine or by ‘regenerative’ braking, which otherwise dissipated in the form of heat to the atmosphere. In order to realize the best use of hybrid vehicles, an optimal power distribution between the engine and battery is required. In this paper dynamic programming technique and rule-based control methods are discussed to develop a power controller which would control the power distribution. Dynamic programming technique cannot be applied for real time applications due to their preview nature and computational complexity. But it is suggested that it can be used to improve efficiency of rule-based control method.