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A point mutation of PRL gene in pituitary prolactin- secreting adenoma induced by 17-β-estradiol in SD rats

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Chinese Science Bulletin 2000年第5期45卷 435-439页

作者： Xuemei wu Rongkun Xu Department of Physiology Institute of Basic Medical Science Chinese Academy of Medical Sciences Beijing China

Animal model bearing pituitary prolactin-secreting adenomas (prolactinoma) induced by 17-β-estradiol (E2) in both eutopic pituitary and ectopic pituitary grafted under the renal capsule was generated. Northern blotting assay indicated that PRL mRNA level in eutopic prolactinomas was higher than that in normal pituitaries and ectopic prolactinomas (P<0.05 - 0.01). By polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) analysis and DNA sequencing, a point mutation from C to A occurring at -36 nt in proximal promoter of rat PRL (rPRL) gene was found only in eutopic prolactinomas. No base change was detected in ectopic prolactinomas. Fusion gene transfection assay in vitro exhibited increased activity of the mutant promoter derived from eutopic prolactinoma (P<0.01). These data suggested that the base change in the proximal promoter of rPRL gene may be associated with hyperexpression of rPRL gene in eutopic prolactinomas. The pathogenesis of eutopic and ectopic prolactinomas

关键词： PCR-SSCP prolactin-secreting adenoma rPRL gene DNA sequencing point mutation.

A parameter-free upwind scheme for all speeds' simulations

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Science China(Technological Sciences) 2015年第3期58卷 434-442页

作者： QU Feng YAN Chao SUN Di YUAN wu National Laboratory for CFD Beihang University Supercomputting Center Computer Network Information Center Chinese Academy of Sciences

With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high *** achieve this goal,we present a new upwind scheme called AUSMPWM in this *** scheme computes the numerical mass flux as the AUSMPW+and computes the interfacial sound speed in a different ***,it computes the pressure flux by limiting the dissipation if the Mach number is less than *** of numerical experiments show that AUSMPWM can satisfy the following attractive properties independent of any tuning coefficient:(1)Robustness against the shock anomaly and high discontinuity’s resolution;(2)high accuracy on hypersonic heating prediction and capability to give smooth reproductions of heating profiles;(3)low dissipation at low speeds;and(4)strong grid,reconstruction scheme,and Mach number independence in low speeds’*** properties suggest that AUSMPWM is promising to be widely used to accurately and efficiently simulate flows of all speeds.

关键词： shock anomaly AUSMPW+ ausmpwm all speeds computational fluid dynamics

Shale gas transport in nanopores with mobile water films and water bridge

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Petroleum Science 2023年第2期20卷 1068-1076页

作者： Ran Li Zhangxin Chen Keliu wu Jinze Xu Department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaT2N 1N4Canada State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China

Gas flow properties in nanopores are significantly determined by the flow patterns. Slug flow pattern is a potential water–gas two phase flow pattern, in which gas molecules flow in form of gas slugs and water molecules separate gas slugs. Considering water slippage, a portion of water molecules accumulates at the wall with lower mobility, while the remaining water molecules take the shape of a water bridge. Adopting foam apparent viscosity model to represent slug rheological behavior, how water bridge disturbs on gas flow capacity is estimated. The results are compared with the water–gas two phase flow model that assumes annular flow pattern as well as the single gas flow model without the consideration of water. The comparison illustrates that gas molecular movement is significantly hindered by flow space reduction and loss of gas slippage. The impact from water phase of slug flow pattern is more significant than that of annular flow pattern on gas flow capacity. It is discovered that larger nanopores improve gas flow capacity while maintaining bulk water layer thickness and increasing water bridge thickness tend to reduce gas transport ability. A better understanding of the structure and transport of water and gas molecules is conducive to figure out the specific gas–water flow behavior and predict shale gas production.

关键词： Shale gas Water bridge Water film Nanopore

Performance evaluation for sustainability of wind energy project using improved multi-criteria decision-making method

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1165-1176页

作者： Jiahui wu Haiyun WANG Weiqing WANG Qiang ZHANG College of Electrical Engineering Xinjiang UniversityUrumqi 830047China State Grid Xinjiang Electric Power Research Institute Urumqi 830011China

Wind power can be an efficient way to alleviate energy shortage and environmental pollution,and to realize sustainable development in terms of energy *** sustainability assessment of a wind project among its alternatives is a complex task that cannot be solely simplified to environmental or economic *** requires the consideration of its technological and social aspects as well as other *** paper proposes a new method for selecting the most sustainable wind *** method is based on multi-criteria decision-making *** analytic hierarchy process and entropy weight method are combined to determine the weights of evaluation indexes,and an innovative index-weight optimization method based on the Lagrange conditional extremum *** fuzzy technique for order preference by similarity to the ideal solution is applied to rank wind project alternatives considering functionality and proportionality of the ***,the sensitive analysis is applied to verify the robustness of the proposed *** applicability of the method is demonstrated on a case study from China,where three main wind projects are analytically compared and *** results indicated that the sustainable level of calculated wind power can provide a reference point for the planning and operation of the wind *** results show that the proposed method is of both theoretical significance and practical application in engineering.

关键词： Analytic hierarchy process Comprehensive evaluation index Entropy method Fuzzy technique Order preference Wind power sustainability level

Fault-tolerant identity-based encryption from SM9

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Science China(Information Sciences) 2024年第2期67卷 104-117页

作者： Xiaohong LIU Xinyi HUANG Zhaohui CHENG Wei wu Fujian Provincial Key Laboratory of Network Security and Cryptology College of Computer and Cyber SecurityFujian Normal University Artificial Intelligence Thrust Information HubThe Hong Kong University of Science and Technology (Guangzhou) Olym Information Security Technology Ltd. Center for Applied Mathematics of Fujian Province School of Mathematics and StatisticsFujian Normal University

This paper initiates the formal study of attribute-based encryption within the framework of SM9,the Chinese National Cryptography Standard for Identity-Based Cryptography, by presenting two new faulttolerant identity-based encryption(FIBE) schemes. Our first scheme uses the same private-key/ciphertext structure as the original SM9 algorithm and operates in a small attribute universe. As a result, it can be effectively and smoothly integrated into the information systems using SM9. In the random oracle model,we prove that our scheme is ciphertext-indistinguishable against fuzzy selective-identity and chosen-plaintext attacks under the(k + 3)-DBDHI assumption. Our second design is a large universe FIBE scheme based on SM9 that is ciphertext-indistinguishable against chosen-plaintext attacks in the random oracle model under the(f, g)-GDDHE assumption. Finally, we compare the communication and computing costs of our schemes to those of other classical ones. The comparison shows that our schemes have comparable performance as others. We believe that our findings will accelerate the applications of SM9 in modern information systems such as cloud computing and blockchain.

关键词： attribute-based encryption identity-based encryption fault-tolerant SM9

Voltage Security Operation Region Calculation Based on Improved Particle Swarm Optimization and Recursive Least Square Hybrid Algorithm

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 138-147页

作者： Saniye Maihemuti Weiqing Wang Haiyun Wang Jiahui wu Xinjiang University UrumqiChina

Large-scale voltage collapse incidences, which result in power outages over large regions and extensive economic losses, are presently common occurrences worldwide. To avoid voltage collapse and operate more safely and reliably, it is necessary to analyze the voltage security operation region(VSOR) of power systems, which has become a topic of increasing interest lately. In this paper, a novel improved particle swarm optimization and recursive least square(IPSO-RLS) hybrid algorithm is proposed to determine the VSOR of a power system. Also, stability analysis on the proposed algorithm is carried out by analyzing the errors and convergence accuracy of the obtained results. Firstly, the voltage stability and VSOR-surface of a power system are analyzed in this paper. Secondly, the two algorithms,namely IPSO and RLS algorithms, are studied *** on this understanding, a novel IPSO-RLS hybrid algorithm is proposed to optimize the active and reactive power,and the voltage allowed to identify the VSOR-surface accurately. Finally, the proposed algorithm is validated by using a simulation case study on three wind farm regions of actual Hami Power Grid of China in DIg SILENT/Power Factory *** error and accuracy of the obtained simulation results are analyzed and compared with those of the particle swarm optimization(PSO), IPSO and IPSO-RLS hybrid algorithms.

关键词： Voltage stability renewable energy improved particle swarm optimization(IPSO) recursive least square(RLS) voltage security operation region(VSOR)

Research on fault detection method for heat pump air conditioning system under cold weather

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1812-1819页

作者： Liangliang Sun Jianghua wu Haiqi Jia Xuebin Liu Information and Control Engineering Shenyang Jianzhu University Electrical Engineering University of Connecticut

Building energy consumption accounts for nearly 40% of global energy consumption, HVAC （Heating, Ventilating, and Air Conditioning） systems are the major building energy consumers, and as one type of HVAC systems, the heat pump air conditioning system, which is more energy-efficient compared to the traditional air conditioning system, is being more widely used to save energy. However, in northern China, extreme climatic conditions increase the cooling and heating load of the heat pump air conditioning system and accelerate the aging of the equipment, and the sensor may detect drifted parameters owing to climate change. This non-linear drifted parameter increases the false alarm rate of the fault detection and the need for unnecessary troubleshooting. In order to overcome the impact of the device aging and the drifted parameter, a Kalman filter and SPC （statistical process control） fault detection method are introduced in this paper. In this method, the model parameter and its standard variance can he estimated by Kalman filter based on the gray model and the real-time data of the air conditioning system. Further, by using SPC to construct the dynamic control limits, false alarm rate is reduced. And this paper mainly focuses on the cold machine failure in the component failure and its soft fault detection. This approach has been tested on a simulation model of the ＂Sino-German Energy Conservation Demonstration Center＂ building heat pump air-conditioning system in Shenyang, China, and the results show that the Kalman filter and SPC fault detection method is simple and highly efficient with a low false alarm rate, and it can deal with the difficulties caused by the extreme environment and the non-linear influence of the parameters, and what＇s more, it provides a good foundation for dynamic fault diagnosis and fault prediction analysis.

关键词： Fault detection Cold machine Kalman filter Statistical process control Dynamic control

Preparation of Large Area Double-walled Carbon Nanotube Macro-films with Self-cleaning Properties

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Journal of Materials Science & Technology 2010年第1期26卷 20-26页

作者： Ziping wu Qianfeng Xu Jiannong Wang Jie Ma School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory for Metallic Functional Materials Key Laboratory for Advanced Civil Engineering Materials (Ministry of Education) School of Materials Science and Engineering Tongji University Shanghai 200029 China

Double-walled carbon nanotube （DWCNT） macro-films with large areas, excellent flexibility and superhydrophobicity are reported. The area of the macro-film is larger than 30 cm×15 cm, and this large film can be bended, or folded without any damage, and even can be tailored freely. After a simple modification of perfluoroalkysilane, the surface of the macro-film shows excellent superhydrophobicity with a water contact angle of 165.74-2 deg. and sliding angle lower than 3 deg., the prepared superhydrophobic films showing excellent antifouling, self-cleaning and water-repellent functions. The topographic roughness and perfluoroalkysilane modification are found to contribute to the observed superhydrophobicity. Considering the outstanding electronic, chemical and mechanical properties of DWCNTs, it is expected that this multifunctional DWCNT macro-film has potential applications in many fields.

关键词： Double-walled carbon nanotubes Large area film Self-cleaning Methanol

Fixed-time adaptive model reference sliding mode control for an air-to-ground missile

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Chinese Journal of Aeronautics 2019年第5期32卷 1268-1280页

作者： Liang ZHANG Changzhu WEI Rong wu Naigang CUI School of Astronautics Harbin Institute of Technology

This paper addresses the fixed-time adaptive model reference sliding mode control for an air-to-ground missile associated with large speed ranges, mismatched disturbances and un-modeled dynamics. Firstly, a sliding mode surface is developed by the tracking error of the state equation and the model reference state equation with respect to the air-to-ground missile. More specifically,a novel fixed-time adaptive reaching law is presented. Subsequently, the mismatched disturbances and the un-modeled dynamics are treated as the model errors of the state equation. These model errors are estimated by means of a fixed-time disturbance observer, and they are also utilized to compensate the proposed controller. Therefore, the fixed-time controller is obtained by an adaptive reaching law and a fixed-time disturbance observer. Closed-loop stability of the proposed controller is established. Finally, simulation results including Monte Carlo simulations, nonlinear six-DegreeOf-Freedom(6-DOF) simulations and different ranges are presented to demonstrate the efficacy of the proposed control scheme.

关键词： Adaptive controller Air-to-ground missile Fixed-time adaptive reaching law Fixed-time disturbance observer Model reference sliding mode control