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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-heng du Yong-Min Shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

Approach to Calculating Methods of Wave Breaking Depth and Height

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China Ocean Engineering 1993年第1期8卷 85-98页

作者： Wang, Liang du, heng Hohai Univ Nanjing China

Engineers in coastal engineering have been paying much attention to the research subject on wave breaking. In this paper, previous research results on the calculating methods of wave breaking depth and height are enumerated, the laws of wave transformation before and after wave breaking are investigated, an adequate supposition is made, and the effect of beach slope, bed friction and breaking turbulence on wave breaking is considered. By applying the theory of wave energy dissipation rate and combining with proper formulas of solitary waves, a new calculating formula of wave breaking depth and height on the movable bed is derived and examined with the data from experimental pools of different sizes, and it is proved to be of practicability.

关键词： Energy dissipation Friction Numerical methods Turbulence

Application of statistical analysis of sample size:How many occupant responses are required for an indoor environmental quality(IEQ)field study

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Building Simulation 2023年第4期16卷 577-588页

作者： heng du Zhiwei Lian Li Lan Dayi Lai Department of Architecture School of DesignShanghai Jiao Tong UniversityShanghai 200240China

Determining required sample size is one of the critical pathways to reproducible,reliable and robust results in human-related *** paper aims to answer a fundamental but often overlooked question:what sample size is required in surveys of occupant responses to indoor environmental quality(IEQ).The statistical models are introduced in order to promote determining required sample size for various types of data analysis methods commonly used in IEQ field *** Monte Carlo simulations are performed to verify the statistical methods and to illustrate the impact of sample size on the study accuracy and *** examples are presented to illustrate how to determine the value of the parameters in the statistical models based on previous similar research or existing *** required sample size including“worst”and“optimal”cases in each condition is obtained by this method and *** is indicated that 385 is a“worst case”sample size to be adequate for a subgroup analysis,while if the researcher has an estimate of the study design and outcome,the“optimal case”sample size can potentially be *** the required sample size is not achievable,the uncertainty in the result can properly interpret via a confidence *** is hoped that this paper would fill in the gap between statistical analysis of sample size and IEQ field research,and it can provide a useful reference for researchers when planning their own studies.

关键词： indoor environmental quality built environment field study sample size thermal comfort

SPACE DEBRIS RESEARCH IN CHINA(2000-2002)

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空间科学学报 2002年第Z1期22卷 39-41页

作者： du heng Center for Space Science and Applied Research The Chinese Academy of SciencesBeijing 100080 China

　　Space debris is is referred to as the human made pollution in the space *** since the first launch of man made satellite in 1957, millions of kilograms of objects have been sent into the space. Large space objects that are traceable and cataloged by ground base telescope and radar reach around 9 000, becoming grave threat to the social development of human beings as well as astronautics.……

关键词： space environment human beings

A sleep staging model for the sleep environment control based on machine learning

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Building Simulation 2023年第8期16卷 1409-1423页

作者： Ting Cao Zhiwei Lian heng du Jingyun Shen Yilun Fan Junmeng Lyu School of Design Shanghai Jiao Tong UniversityShanghai 200240China

To date,dynamic sleep environment has been attracted the focus of *** to the individual difference on sleep phase and thermal comfort,changes in sleep environment should be occupant-centered,and precise regulation of the environment required current sleep ***,few studies connected occupants and the environment through physiological signal-based model of sleep ***,this study tried to develop a data driven sleep staging model with higher accuracy through sleep experiments collecting *** database was processed and selected efficiently according to the characteristics of physiological ***,the sleep staging model with an average accuracy of 93.9%was built,and other mean indicators(precision:82.5%,recall:83.1%,F1 score:82.8%)performed *** features adopted by model were found to come from different brain regions,and the global brain signals were suggested to play an important role in the construction of sleep staging ***,the computational processing of physiology signals should consider their characteristics,i.e.,time domain,frequency domain,time-frequency domain and nonlinear *** model obtained in this study may deliver a credible reference to advance the research on control of sleep environment.

关键词： sleep environment sleep staging model physiological signals machine learning environmental control

Parametric study on the sleep thermal environment

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Building Simulation 2022年第5期15卷 885-898页

作者： Ting Cao Zhiwei Lian Jingwen Zhu Xinbo Xu heng du Qiantao Zhao School of Design Shanghai Jiao Tong UniversityShanghai 200240China

Sleep thermal environment has a great effect on occupants7 sleep *** purpose of this study was to explore the relationships between sleep thermal environment parameters and sleep quality in winter and *** whole experiments involved indoor ambient temperatures(winter:17℃,20℃,23℃;summer:23℃,26℃,29℃)and relative humidity(RH;winter:40%,55%,70%;summer:40%,60%,80%).A total of 18 young subjects(23±2 years old)were divided into the two different season groups to experience the corresponding environmental *** subjective environmental perception and objective physiological signals were *** results showed that thermal sensations at 20℃in winter,as well as 26℃in summer,were considered as the thermal neutral *** sensation in winter before sleep was susceptible to SET*,while the middle value of SET*(32℃)related to the middle indoor air temperature(26℃)and air humidity(60%)before and after sleep could be the summer combination of neutral thermal ***,cold and wet environment in winter was found to seriously affect the deep *** summer,mild temperature contributing to good sleep quality might weaken the effect of humidity on *** combining the sleep environmental perception result with contour line and regression analysis on objective sleep quality,the suggested values of thermal environment parameters for young adults(21-25 years old)were as follows:20.3℃and 56%RH in winter,as well as 26.1℃and 52%RH in summer.

关键词： sleep thermal environment moderate parameters thermal sensation humid sensation interaction effect-regression analysis

Two-plane painting injection scheme for BRing of HIAF

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Nuclear Science and Techniques 2017年第8期28卷 47-53页

作者： Guo-Feng Qu Wei-Ping Chai Jia-Wen Xia Jian-Cheng Yang heng du Zhong-Shan Li Wen-Wen Ge Wen-heng Zheng Peng Shang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100046China

The high-intensity heavy-ion accelerator facility(HIAF)is under design at the Institute of Modern Physics(IMP)and will provide an intense ion beam for nuclear physics,atomic mass measurement research,and other *** the main ring of HIAF,the BRing accumulates beams to high intensity and accelerates them to high *** achieve high intensities up to 1×10^(11)(^(238)U^(34+)),the injection gain of the BRing must be as high as ***,multiple multiturn injection supported by the electron cooling system takes a long time,causing substantial beam loss under a strong space charge ***,a two-plane painting injection scheme is proposed for beam accumulation in the *** scheme uses a tilted injection septum and horizontal and vertical bump magnets to paint the beam into horizontal and vertical phase space *** this paper,the two-plane painting injection parameters are optimized,and the resulting injection process is simulated using the Objective Ring Beam Injection and Tracking(ORBIT)*** injection gain of up to 110.3 with a loss rate of 2:3%is achieved,meeting the requirements of BRing.

关键词：绘画平面近代物理研究所注射过程重离子加速器电子冷却系统束流损失纵向相空间

Patent eligibility of software inventions

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China Intellectual Property 2021年第4期 88-94页

作者： du heng Patent Examination Cooperation Jiangsu Center of the Patent Office CNIPA

Article 25 of the Patent Law provides for six types of subject matters for which no patent right should be *** matter how practical,novel or inventive they are,specific results covered by such subject matters are excluded from patent ***,the determination of ineligible subject matters does not require evidence to aid comparison as in the case of commenting on novelty or inventiveness,which can be concluded directly and merely by deductive ***,it is particularly important to clearly define the concept of the various statutory exclusions in the article.

关键词： Patent protection. patent

Effect of VIATORR stent in early ultrasound evaluation after transjugular intrahepatic portosystemic shunt(TIPS): A case report

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Journal of Interventional Medicine 2020年第2期3卷 106-108页

作者： heng du Yong Yao Suyu He Lei Feng Hang Wu Department of Gastroenterology Suining Central HospitalSuining629000China Department of Ultrasonography Suining Central HospitalSuining629000China

Shunt dysfunction is a major complication of transjugular intrahepatic portosystemic shunt(TIPS). Ultrasonography is a preferred method of shunt follow-up after TIPS, but some misjudgments can occur in cases of shunt dysfunction due to peculiarities of the VIATORR stent. Here we report one case and suggest that the first ultrasound evaluation for patients who received TIPS procedure with VIATORR stent should be performed one month after the procedure.

关键词： Ultrasonography Doppler Color Portosystemic shunt Transjugular intrahepatic VIATORR stent Case report

In-situ measurement on air-water flux of CH_(4),CO_(2) and their carbon stable isotope in lakes of northeast Tibetan Plateau

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Advances in Climate Change Research 2022年第2期13卷 279-289页

作者： Lei WANG Cun-De XIAO Zhi-heng du Damien T.MAHER Jing-Feng LIU Zhi-Qiang WEI State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Southern Cross Geoscience Southern Cross UniversityLismoreNSW 2480Australia College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Zhuhai Branch of State Key Laboratory of Earth Surface Process and Resource Ecology Beijing Normal UniversityZhuhai 519087China

Inland waters are important sources of greenhouse gases(GHGs)to the atmosphere that may partially offset the terrestrial carbon ***,GHG emissions from high altitude saline lakes on the Tibetan Plateau are currently poorly *** this study,we measured methane(CH_(4))and carbon dioxide(CO_(2))concentrations and their carbon stable isotope(δ13C),and calculated diffusive water-to-air fluxes from two saline high-altitude lakes,Qinghai Lake and Hala Lake,located in northeast Tibetan Plateau in October *** two lakes were mostly supersaturated in CH_(4)(89.8%-4623.9%sat)and acted as sources of CH_(4) to the ***,more than 96%investigated area of Qinghai Lake and all investigated area of Hala Lake was a sink of CO_(2).The average diffusive fluxes of CH_(4) and CO_(2) in the surface waters of Qinghai Lake were 34.51μmol m−2 d−1 and−1.29 mmol m−2 d−1,while diffusive fluxes of CH_(4) and CO_(2) in Hala Lake averaged 5.48μmol m−2 d−1 and−5.24 mmol m−2 d−1,***(Sal),fluorescent dissolved organic matter(fDOM),temperature(Temp)and dissolved oxygen(DO)are key factors for diffusive CH_(4) and CO_(2) flux in Qinghai Lake and Hala ***_(4) diffusive fluxes across water-air interface from Qinghai Lake and Hala Lake were found to be significantly lower than other freshwater lakes,likely due to their saline nature.A simple isotope mixing model(Miller-Tans plots)revealed a distinctly different isotopic source values of CO_(2) and CH_(4) in Qinghai Lake and Hala *** CH_(4) production pathway of Qinghai Lake was mainly by the acetate fermentation,while that of Hala Lake was mainly by the CO_(2) *** results show that the continuous measurement can help capture the spatial variability of GHGs fluxes in saline lakes.

关键词： Greenhouse gas Air-water flux Carbon stable isotope Tibetan Plateau Saline lakes