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Focus on research advances in the natural gas hydrate resource evaluation: Introduction to papers in the special section of Evaluation of Natural Gas Hydrate Resource Potential in the South China Sea

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Petroleum Science 2022年第1期19卷 1-2页

作者： De-li gao Academician of Chinese Academy of Sciences Professor at China University of PetroleumBeijing 100083China

The continental hydrocarbon generation theory has opened a new field of oil and gas development and once solved the oil and gas shortage problem in *** then,geological theories of coalbed methane accumulation,foreland basin oil and gas accumulation,carbonate rock oil and gas accumulation,superimposed basin,and deep oil and gas accumulation have contributed to relieving the pressure of oil and gas shortage in China.

关键词： China. basin carbonate

Influences of environmental factors on the spawning stock-recruitment relationship of Portunus trituberculatus in the northern East China Sea

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Acta Oceanologica Sinica 2021年第8期40卷 145-159页

作者： li gao Yingbin Wang School of Fishery Zhejiang Ocean UniversityZhoushan 316022China

Based on the Ricker-type models,the spawning stock-recruitment(S-R)relationship of Portunus trituberculatus was analysed under the impacts of environmental factors(including red tide area(AORT),sea level height(SLH),sea surface salinity(SSS)and typhoon landing times(TYP))in the northern East China Sea in 2001 and *** the traditional Ricker model,two other Ricker-type S-R models were built:Ricker model with ln-linear environmental impact(Ricker-type 2)and Ricker model with ln-quadratic polynomial environmental impact(Ricker-type 3).Results showed that AORT,SLH,SSS and TYP had great influences on the recruitment of *** SSS reached 29 and 31,recruitment decreased from 20.7×10^(3) million to 8.3×10^(3) million *** this case,recruitment declined,whereas AORT and TYP *** of the S-R model showed that the Akaike information criterion(AIC)value of the traditional Ricker model was 14.619,which remarkably decreased after addition of the environmental *** numbers of environmental factors were added to the Ricker model,and the best result was obtained when four factors were added to the model ***,Ricker-type 2 model,with the AIC value of-5.307,was better than Ricker-type 3 model(add above four environmental factors at the same time).The findings indicated that the mechanisms by which various environmental factors affect the S-R relationship are different.

关键词： Portunus trituberculatus Ricker model environmental dependent recruitment East China Sea

Study on the Diffusion Performance of Standard E-Government Information Systems

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China Communications 2016年第5期13卷 182-202页

作者： Jing Fan li gao Jinping gao International Business School Beijing Foreign Studies University School of Business and Management Shanghai International Studies University School of Economics and Management Beijing University of Posts and Telecommunications

Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only for avoiding redundant e-government IS development but also for improving collaboration among government agencies. Two research questions were explored: what are the factors influencing the performance of SEIS? Will mandatory SEIS create a better performance than non-mandatory SEIS? Specifically, the use of five categories of IS aspects--information system quality, online service quality, offline service quality, diffusion modes and standard network size—is proposed to understand the performance of SEIS through applying both survey study and simulation study. The results show that information system quality and online service quality of SEIS have strong effects on users' expectation and users' satisfaction, which thereafter promotes the performance of SEIS. Government agencies' offline service quality shows a significant effect on users' satisfaction while not on users' expectation. Furthermore, the diffusion speed of SEIS in non-mandatory and mandatory modes and the standard network size also have great influence on the utility of SEIS.

关键词： standard e-government IS mobile-government application information system quality online service quality offline service quality diffusion modes network size

Relations among homogeneity, collapsibility and nonconfounding in distribution effects

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 291-296页

作者： WANG Xue-li gao li School of Science Beijing University of Posts and Telecommunications Beijing 100876 China Department of Mathematics Binzhou University Shandong 256600 China

In this paper, the concept of distribution effect is proposed without the causal diagram. Following the notation of Stone [11], we assume that the exposure treatment X is an unknown deterministic function of the confounder set Pa（X） and a random error ε. We discuss sufficient and necessary conditions for homogeneity, collapsibility and nonconfounding for distribution effects and discuss relations among them.

关键词： Collapsibility confounding homogeneity distribution effect.

Analysis of drilling difficulty of extended-reach wells based on drilling limit theory

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Petroleum Science 2022年第3期19卷 1099-1109页

作者： Wen-Jun Huang De-li gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

With the continuous increase in vertical depths and horizontal displacements of directional wells,the difficulties of drilling operations continue to increase,and more accurate methods of drilling difficulty evaluation are *** this paper,a drilling difficulty evaluation method is built by combining drilling limit model and expert ***,the concept of drilling difficulty index is introduced,and the method to calculate drilling difficulty index is ***,the meanings of five drilling difficulty levels are explained and the optimization design method with drilling difficulty as the target is *** last,the theoretical model is applied to the extended-reach drilling of the liuhua oilfield in the South China Sea,in which drilling difficulties are evaluated and the relationship between drilling difficulty and development control radius is *** results indicate that extended-reach drilling in the liuhua oilfield is on the“normal”difficulty level on average,rotary drilling in 8_(1/2)-*** is the most difficult,and the main constraint conditions are excessive torque and high *** technology upgradation,the drilling difficulties are decreased,the development control radius increases from 6.6 to 11.4 km,and the maximum horizontalto-vertical ratio increases from 5.3 to ***,the development wells in marginal oilfields and adjustment wells in old oilfields can be drilled on“normal”difficulty ***,technology upgradation,especially drilling rig upgradation,is the most important development direction for extended-reach drilling in the South China Sea.

关键词： Extended-reach drilling South China Sea Drilling limit Drilling difficulty evaluation Drilling optimization design

Evaluation of zeotropic refrigerants based on nonlinear relationship between temperature and enthalpy

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Science China(Technological Sciences) 2006年第3期49卷 322-331页

作者： ZHAO li gao Pan Department of Thermal and Refrigeration Engineering School of Mechanical Engineering Tianjin University Tianjin 300072 China Department of Thermal and Refrigeration Engineering School of Mechanical Engineering Tianjin University Tianjin 300072 China

In order to evaluate cycling characters of zeotropic refrigerants in air-con- ditioning operation, and to reveal distribution rules of temperature difference between refrigerants and heat transfer fluids in condenser and evaporator, theoretical researches were carried out based on nonlinear relationship between temperature and enthalpy in period of refrigerants’ phase change. Firstly, a phase changing model of refrigerants was built, and refrigerants state parameters were decided in the air-conditioning operation. Secondly, the state equation of refrigerants was applied for computing relationship be- tween temperature and enthalpy, else based on some suppositions, temperature differ- ences between 15 sorts of refrigerants and heat-transfer fluids were gotten too. Through concluding those temperature differences changing in condenser and evaporator, some rules were found. Lastly, after calculating and comparing the additive exergy loss among 15 sorts of refrigerants, which resulted from the changing of temperature difference, their cycling characters evaluation were presented.

关键词： zeotropic refrigerants, evaluation, phase change, temperature distribution, the additive exergy loss,air conditioning operation.

General radiation via tunneling in Kerr and Kerr-Newman black holes

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1200-1205页

作者： gao li liU WenBiao Department of Physics Institute of Theoretical PhysicsBeijing Normal UniversityBeijing 100875China

Hawking radiation can be viewed as a process of quantum tunneling near the black hole horizon. When a particle with angular momentum L≠ω a tunnels across the event horizon of Kerr or Kerr-Newman black hole, the angular momentum per unit mass a should be changed. The emission rate of the massless particles under this general case is calculated, and the result is consistent with an underlying unitary theory.

关键词： Hawking radiation black hole Bekenstein-Hawking entropy quantum unitary theory Painleve coordinates

New progress in active immunotherapy targeting to amyloid beta

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Science China Chemistry 2015年第3期58卷 383-389页

作者： gao li Yong-Xiang Chen Yan-Mei li Key Lab of Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing Institute for Brain Disorders

Alzheimer's disease(AD) is one of the most common types of dementia whose hallmarks include neurofibrillary tangles and senile plaques. The latter are mainly composed of amyloid-β proteins(Aβ), and it's suggested that Aβ may be the causative factor in AD pathogenesis. Immunotherapy targeting Aβ for preventing aggregation of Aβ and mildly clearing amyloid plaques has been a hot topic since 1999. Although the first clinical trial of Aβ vaccine, AN-1792, failed in phase II, its results suggested some key points in the design of Aβ vaccines. Avoiding the possible toxic Aβ specific T cell response and inducing a Th2 type cellular immune response may be beneficial for Aβ immunotherapy. Many associations and research groups are working on Aβ vaccine and some progress has been made in recent years. In this review, we have provided a detailed summary of past Aβ vaccines, which have been sorted by the immunogen, and we also discuss some recent progress and future perspectives.

关键词： Alzheimer's disease amyloid beta active immunotherapy peptide vaccine DNA vaccine

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-li Wang Wen-Jun Huang De-li gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： Deep well Casing integrity Casing wear Casing corrosion Burst strength