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A MODIFIED HIGH-ORDER CUMULANT MUSIC ALGORITHM FOR SIGNAL DOA ESTIMATION

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Journal of Electronics(china) 2000年第4期17卷 319-324页

作者： He Zishu Li Yong Huang Zhenxing (college of Electron. Eng., university of Electronic Science & technology of china, Chengdu 610054)

This paper gives a MUSIC signal DOA estimation algorithm based on the modified high-order cumulant matrix which is constructed by the recieved data and their conjugate rearrangements. When the snapshot number is limited, this algorithm can improve the signal DOA estimation performances obviously, and its computational complexity scarcely increases. Finally, some simulation results to verify the theoretical analyses are presented.

关键词： High-order cumulant MUSIC algorithm Signal DOA estimation Array signal processing

EFFECT OF LASER CLADDING ON HYDROGEN EMBRITTLEMENT RESISTANCE OF AUSTENITIC STAINLESS STEEL

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Chinese Journal of Aeronautics 1997年第1期10卷 36-40页

作者： Pan Qingyue Huang Weidong Lin Xin Zhou Yaohe(State Key Laboratory of Solidification Processing, NorthwesternPolytechnical university, Xi’an, china, 710072)Tan Yun Feng Jie(Chinese Academy of Engineering physics,Chengdu, china, 610003) State Key Lab. Solidification Proc. NW Polytechnical University Xi'an 710072 China Chinese Acad. of Engineering physics Chengdu 610003 China

A plasma spraying plus laser remelting technique has been performed. onaustenite stainless steel (22Cr-13Ni-5Mn ) with a newly developed hydrogen resistantcoating material. The results show that the surface cladding layer can effectively reducethe hydrogen content increasing of the stainless steel under the atmosphere of high pres-sure (30MPa), high temperature (300℃) and high purity (99. 995%) hydrogen andgreatly improve the hydrogen embrittlement resistance of the stain1ess steel. Throughanalysis of microstructure, a mechanism of hydrogen embrittlement resistance is presentedthat at room temperature, the surface oxidation films, both existing on the surface ofcoated and uncoated specimens, inhibit the adsorption and diffusion of hydrogen molecu-lae. However, at high temperature, it is the surface cladding layer with relatively low sol-ubility and Permeability for hydrogen that significantly reduces the amount of hydrogenentering into the interior of the material and improves its hydrogen embrittfement resis-tance.

关键词： laser applications cladding hydrogen embrittlement austenitic stainless steels hydrogen content

A Cooperation-planning Model Based on Bilevel Programming Decision

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武汉理工大学学报 2006年第S3期28卷 940-945页

作者： ZHANG Jianfeng ZHOU Lei BAO Zhenqiang BIAN Wenyu LI Xiangqing Information Engineering college,Yangzhou university,Yangzhou 225009,china, Information Engineering college Yangzhou UniversityYangzhou 225009China

This paper is based on a resource constrained active network project;the constraint of the local resource and the time constraint of the cooperation resource are considered *** the respective benefit of the manager and cooperation partners is also considered *** a cooperation planning model based on bilevel multi-objective programming is de- signed,according to the due time and total *** an extended CNP based on the permitted range for resource and time requests is presented.A larger task set in scheduling cycle is on the permitting for the request of cooperation resource and time while the task manager itself may be permitted biding for *** a result,the optimization space for the cooperation planning is *** not every bidding task is successfully bid by invitee,and the task manager itself takes on some bidding ***,the genetic algorithm is given and the validity and feasibility of the model is proved by a case.

关键词： bilevel programming decision cooperation planning genetic algorithm range for resource and time sequest

A New Secure Password Authentication Scheme Using Smart Cards

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Wuhan university Journal of Natural Sciences 2008年第6期13卷 739-743页

作者： WANG Bangju1,2, WANG Yuhua3, ZHANG Huanguo1 1. School of Computer, Wuhan university/Key Laboratory of Aerospace Information Security and Trust Computing of Ministry of Education, Wuhan 430072, Hubei, china 2. School of Science, Huazhong Agricultural university, Wuhan 430070, Hubei, china 3. college of Information Science and Engineering, Henan university of technology Zhengzhou 450001, Henan, china School of Computer Wuhan University/Key Laboratory of Aerospace Information Security and Trust Computing of Ministry of Education Wuhan China School of Science Huazhong Agricultural University Wuhan China college of Information Science and Engineering Henan University of Technology Zhengzhou China

Thirteen security requirements for an ideal password authentication scheme using smart cards are listed and a new smart card based password authentication scheme with identity anonymity is proposed. The new scheme can satisfy all the listed ideal security requirements and has the following merits：（1） it can resist all the attacks listed in introduction; （2） less storage memory requirement due to no verification table stored in server; （3） low computational cost due to hash functions based operations; （4） even if the smart card is lost, the new system is still secure; （5） As user identity is anonymous, this scheme is more practical. The new proposed scheme can be applied in source constraint networks.

关键词： password password authentication hash function attack smart card

MESON SPECTROSCOPY IN THE HEAVY STRATON MODEL

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Science china Mathematics 1983年第5期30卷 512-522页

作者：丁亦兵赵光达 Graduate School University of Science and Technology of China Beijing physics Department Peking University

Assuming that the bare mass of the straton is very large and that the interaction of the straton and antistraton is instantaneous in the rest frame of the meson and taking the form of V0 γ,×γ5+V1γ4×γ4×V2γ×γ, we solve the B-S equation for mesons. The mass formula m2=（m1+m2）2+2（m1+m2）E is obtained, where m1 （m2） is the effective mass of the straton （antistraton） inside the meson and E is the eigenvalue of the Schrdinger equation. The obtained mass spectra including both light mesons and heavy mesons agrce with experimental data. Our model may provide a possille explanation for the question why the nonrelativistic Schrdinger equation can be used even for hadronic systems composed of u, d, s stratons, though their effective mass is very small.

关键词： MESON SPECTROSCOPY IN THE HEAVY STRATON MODEL

HAND-HELD STATE MONITORING AND FAULT DIAGNOSIS SYSTEM FOR OIL FIELD POURING AND PICK EQUIPMENT

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HAND-HELD STATE MONITORING AND FAULT DIAGNOSIS SYSTEM FOR OI...

Separation of cobalt and nickel by non-equilibrium solvent extraction

International technology and Innovation Conference 2006

作者： LI Peiyu, TAN Dapeng, LIU Duanyang college of Mechanical and Energy Engineering, Zhejiang university, Hangzhou 310027, china college of Information Engineering, Zhejiang university of technology, Hangzhou 310024, china

＜正＞There are a lot of problems in pouring and pick equipments （PPE） which are widely applied in oil field, such as many different kinds of faults, dispersal of equipments, strict requirement for continuous working etc. But traditional fault diagnosis technology （FDT） based on PC doesn’t have adequate flexibility, so it can not satisfy the requirements as mentioned before. To solve these problems, a new kind of hand-held state monitoring and fault diagnosis system （SM-FDS） based on embedded technology was put forward. After detailed analysis of working situation and operating features of PPE, the realization way which is mainly based on the index of vibration is confirmed;Using multi-channel data collecting technology, hand-held circuit check is realized in real-time data collecting process. Signal analysis component library and graphical user interfaces （GUI） component library which can reconstruct and occupy small space are established to make characteristic extraction of signal, on-line analysis and diagnosis by multi-kind signal analysis method. According to specific requirements of hand-held instruments, monitoring system which has upper-lower position computer with dual-CPU computer architecture and low power consumption designation is realized. Industry experiments indicated that this system monitors accurately, works stably, and has a bright application future.

关键词： Pouring and pick equipment hand-held embedded system fault diagnosis signal analysis.

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Journal of Central South university of technology 2001年第1期8卷 50-53页

作者： WANG Kai yi, NIU Cong wei, QIAN Dong, LIU Ju hong, CHEN Xiao yi, LAI De yong (college of Chemistry and Chemical Engineering, Central South university, Changsha 410083, china) college of Chemistry and Chemical Engineering Central South University Changsha China

The separation of cobalt and nickel in the ammoniacal sulfate solution by non equilibrium solvent extraction with a phosphate (P303) as extractant was studied. In the experiment, the effects of equilibrium pH value in aqueous phase, contact time of the two phases, the air blowing time for feed liquor in the open beaker on percentage extraction of cobalt and nickel and percentage reextraction of nickel from the loaded organic phase with dilute H 2SO 4. etc were studied. The results showed that: Co(Ⅱ) can be oxidized to Co(Ⅲ) ammino complex by adding (NH 4) 2S 2O 8 or blowing air to the aqueous phase, and Co(Ⅲ) ammino complex is a kind of kinetically inert complex. Its extractive speed is very slow, while the nickel′s is much faster than that of cobalt. By controlling the contact time of the two phases, nickel can be separated from cobalt by non equilibrium solvent extraction. Then nickel was reextracted from the loaded organic phase with dilute H 2SO 4.

关键词： non equilibrium solvent extraction separation cobalt nickel

Potent Antioxidative Potential of Propofol during Cardiopulmonary Bypass in the Adult

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Journal of Huazhong university of Science and technology(Medical Sciences) 2001年第4期21卷 349-352页

作者：张诗海姚尚龙 Department of Anesthesiology Xiehe Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan

The potent antioxidative potential of propofol during cardiopulmonary bypass (CPB) in adults was investigated. The selected 30 patients receiving open heart surgery under CPB were randomly divided into group A and group B. The patients in the group A and group B were given propofol (0.1 *** -1 .min -1 ) and fentanyl (5 μ*** -1 .min -1 ) respectively to maintain anesthesia after aorta was cross clamped. Blood samples were drawn pre anesthesia, pre CPB, at 30 min of CPB, at the end of CPB, at 1 h after CPB, at the end of operation, at 12.and 24 h postoperatively. RBC suspension was prepared and erythrocyte glucose 6 phosphate dehydrogenase (G 6 PD) and phosphofructokinase (PFK) activities, total erythrocyte reduced glutathione (GSH) and oxidized GSH (GSSG) were assayed and GSH/GSSG ratio was calculated. In the group A, G 6 PD and PFK activities and GSH/GSSG ratio were almost uneventfully during CPB and postoperatively. In the group B, G 6 PD activity was increased and PFK activity and GSH/GSSG ratio decreased significantly from 30 min of CPB until 12.h postoperatively. It was demonstrated that propofol could obviously attenuate free radical activity during CPB, while fentanyl has no effect on free radical reduction. Propofol could be beneficial as an anesthetic in patients presenting pathologies associated with free radical reactions during CPB.

关键词： propofol cardiopulmonary bypass free radicals

On a Boolean-valued Model of the Strict Implication System(Continuous)

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Chinese Quarterly Journal of Mathematics 2004年第4期19卷 346-349页

作者： LI Na, LIU Hua-ke(1.Department of Philosophy, Nankai university, Tianjin 300071, china 2. college of Mathematics and Information Science, Henan university, Kaifeng 475001, china) Department of Philosophy Nankai UniversityTianjin 300071 China college of Mathematics and Information Science Henan University Kaifeng 475001China

The reference [4] proved the consistency of S1 and S2 among Lewis' five strict implication systems in the modal logic by using the method of the Boolean-valued model. But, in this method, the consistency of S3, S4 and S5 in Lewis' five strict implication systems is not decided. This paper makes use of the properties: (1) the equivalence of the modal systems S3 and P3, S4 and P4; (2) the modal systems P3 and P4 all contained the modal axiom T(□p → p); (3) the modal axiom T is correspondence to the reflexive property in VB. Hence, the paper proves: (a) ‖As31‖ = 1; (b) ‖AS41‖ = 1; (c) ‖AS5l‖ = 1 in the model(where B is a complete Boolean algebra, R is reflexive property in VB). Therefore, the paper finally proves that the Boolean-valued model VB of the ZFC axiom system in set theory is also a Boolean-valued model of Lewis' the strict implication system S3, S4 and S5.

关键词： the strict implication system Boolean-valued model Boolean value