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Multi-Value Sequence Generated over Sub Extension Field and Its Properties
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作者 Md. Arshad Ali Yuta Kodera +3 位作者 Takuya Kusaka Satoshi Uehara Yasuyuki Nogami Robert H. Morelos-Zaragoza 《Journal of Information Security》 2019年第3期130-154,共25页
Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an... Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an approach for generating a pseudo-random multi-value sequence (including a binary sequence) by utilizing a primitive polynomial, trace function, and k-th power residue symbol over the sub extension field. All our previous sequences are defined over the prime field, whereas, proposed sequence in this paper is defined over the sub extension field. Thus, it’s a new and innovative perception to consider the sub extension field during the sequence generation procedure. By considering the sub extension field, two notable outcomes are: proposed sequence holds higher linear complexity and more uniform distribution of bit patterns compared to our previous work which defined over the prime field. Additionally, other important properties of the proposed multi-value sequence such as period, autocorrelation, and cross-correlation are theoretically shown along with some experimental results. 展开更多
关键词 PSEUDO-RANDOM SEQUENCE Trace Function Power RESIDUE Symbol SUB extension field AUTOCORRELATION CROSS-CORRELATION Linear Complexity Distribution of Bit Patterns
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An efficient algorithm for factoring polynomials over algebraic extension field 被引量:1
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作者 SUN Yao WANG DingKang 《Science China Mathematics》 SCIE 2013年第6期1155-1168,共14页
An efficient algorithm is proposed for factoring polynomials over an algebraic extension field defined by a polynomial ring modulo a maximal ideal. If the maximal ideal is given by its CrSbner basis, no extra Grbbner ... An efficient algorithm is proposed for factoring polynomials over an algebraic extension field defined by a polynomial ring modulo a maximal ideal. If the maximal ideal is given by its CrSbner basis, no extra Grbbner basis computation is needed for factoring a polynomial over this extension field. Nothing more than linear algebraic technique is used to get a characteristic polynomial of a generic linear map. Then this polynomial is factorized over the ground field. From its factors, the factorization of the polynomial over the extension field is obtained. The algorithm has been implemented in Magma and computer experiments indicate that it is very efficient, particularly for complicated examples. 展开更多
关键词 algorithm FACTORIZATION algebraic extension field
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An Introduction to the Theory of Field Extensions
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作者 Saviour Chibeti Iness Kyapwanyama +1 位作者 Henry M. Phiri Jeromy Kalunga 《Advances in Pure Mathematics》 2023年第2期103-132,共30页
This paper unfolds and reviews the theory of abstract algebra, field extensions and discusses various kinds of field extensions. Field extensions are said to be algebraic or transcendental. We pay much attention to al... This paper unfolds and reviews the theory of abstract algebra, field extensions and discusses various kinds of field extensions. Field extensions are said to be algebraic or transcendental. We pay much attention to algebraic extensions. Finally, we construct finite extensions of Q and finite extensions of the function field over finite field F<sub>p </sub>using the notion of field completion, analogous to field extensions. With the study of field extensions, considering any polynomial with coefficients in the field, we can find the roots of the polynomial, and with the notion of algebraically closed fields, we have one field, F, where we can find the roots of any polynomial with coefficients in F. 展开更多
关键词 fields extension fields Algebraic and Transcendental extension Algebraic Closure Algebraically Closed field Absolute Value COMPLETION P-Adic field and field of Formal Laurent Series
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CONVERGENCERATESIN THESTRONG LAWSOFASYMPTOTICALLY NEGATIVELY ASSOCIATEDRANDOM FIELDS 被引量:53
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作者 Zhang Lixin\ Wang Xiuyun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1999年第4期406-416,共11页
In this paper, a notion of negative side ρ \|mixing ( ρ\+- \|mixing) which can be regarded as asymptotic negative association is defined, and some Rosenthal type inequalities for ρ\+- \|mixing random fields are est... In this paper, a notion of negative side ρ \|mixing ( ρ\+- \|mixing) which can be regarded as asymptotic negative association is defined, and some Rosenthal type inequalities for ρ\+- \|mixing random fields are established. The complete convergence and almost sure summability on the convergence rates with respect to the strong law of large numbers are also discussed for ρ\+-\| mixing random fields. The results obtained extend those for negatively associated sequences and ρ\+*\| mixing random fields. 展开更多
关键词 Rosenthal-type inequality strong law of large num bers ρ- -m ixing ρ-m ixing asym p-totic negative association random fields
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Abnormality Degree Detection Method Using Negative Potential Field Group Detectors 被引量:1
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作者 ZHANG Hongli LIU Shulin +3 位作者 LI Dong SHI Kunju WANG Bo CUI Jiqiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期983-993,共11页
Online monitoring methods have been widely used in many major devices, however the normal and abnormal states of equipment are estimated mainly based on the monitoring results whether monitored parameters exceed the s... Online monitoring methods have been widely used in many major devices, however the normal and abnormal states of equipment are estimated mainly based on the monitoring results whether monitored parameters exceed the setting thresholds. Using these monitoring methods may cause serious false positive or false negative results. In order to precisely monitor the state of equipment, the problem of abnormality degree detection without fault sample is studied with a new detection method called negative potential field group detectors(NPFG-detectors). This method achieves the quantitative expression of abnormality degree and provides the better detection results compared with other methods. In the process of Iris data set simulation, the new algorithm obtains the successful results in abnormal detection. The detection rates for 3 types of Iris data set respectively reach 100%, 91.6%, and 95.24% with 50% training samples. The problem of Bearing abnormality degree detection via an abnormality degree curve is successfully solved. 展开更多
关键词 negative potential field group detector(NPFG-detector) data negative Gaussian field kernel density estimation abnormality degree
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Negative Haloes and Geochemical Field Systems of Hydrothermal Deposits 被引量:1
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作者 Ji Kejian, Wang Liben, Lu Fengxiang, Wang Wuyi and Zhang Jianhua Institute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1993年第2期195-209,共15页
Primary haloes of hydrothermal deposits were previously considered as positive haloes. Although it has been recently suggested that primary haloes incude positive and negative ones, almost all the research work on pri... Primary haloes of hydrothermal deposits were previously considered as positive haloes. Although it has been recently suggested that primary haloes incude positive and negative ones, almost all the research work on primary haloes has still focused on positive haloes for various reasons. In order to understand the source of ore substances a number of large hydrothermal deposits related to magmatism including porphyry, skarn and vein type deposits have been studied. It has been found that negative haloes exist on the peripheries of positive haloes of a mineral deposit. On the basis of the study the authors propose the concept of the geochemical field system of ore-forming elements of hydrotherreal deposits, i. e., with the orebody as the centre outwards there occur the mineralized field, positive halo field, depleted field and background field successively. 展开更多
关键词 hydrothermal deposit negative halo geochemical field system
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On the Composite Fields of Two Cubic Cyclic Extension Fields Over a Number Field
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作者 蓝以中 《Chinese Science Bulletin》 SCIE EI CAS 1993年第1期19-22,共4页
Assume that K is a number field, L<sub>i</sub>=K(D<sub>i</sub><sup>1/2</sup>)(i=1, 2), where D<sub>1</sub>, D<sub>2</sub>∈K\K<sup>2</sup> and ... Assume that K is a number field, L<sub>i</sub>=K(D<sub>i</sub><sup>1/2</sup>)(i=1, 2), where D<sub>1</sub>, D<sub>2</sub>∈K\K<sup>2</sup> and L<sub>1</sub>≠L<sub>2</sub>. Let L=L<sub>1</sub>L<sub>2</sub>. It is well-known that L/K has three intermediate subfields of degree 2, which are L<sub>1</sub>, L<sub>2</sub> and L3=K(D<sub>1</sub>D<sub>2</sub><sup>1/2</sup>). 展开更多
关键词 CUBIC CYCLIC extension field composite field INTERMEDIATE subfield.
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A COMPLETE DETERMINATION OF THE CUBIC CYCLIC EXTENSION FIELDS OF NUMBER FIELDS
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作者 蓝以中 《Chinese Science Bulletin》 SCIE EI CAS 1989年第12期973-976,共4页
The fundamental topic of algebraic number theory is to determine all Galois extension fields of a number field. The class field theory determines all Abelian extension fields of a number field on theoretical, but it i... The fundamental topic of algebraic number theory is to determine all Galois extension fields of a number field. The class field theory determines all Abelian extension fields of a number field on theoretical, but it is not concrete. The author has studied the arithmetic properties of cubic cyclic extensions of number fields in [1, 2]. In this report, we determine all cubic cyclic extension fields of any number field K. 展开更多
关键词 number field CUBIC CYCLIC extension SPLITTING COMPLETELY PRIME ideal.
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Properties study of LiNbO_3 lateral field excited device working on thickness extension mode
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作者 张志甜 张超 +3 位作者 王文炎 马廷锋 刘岩 冯冠平 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期584-589,共6页
This paper investigates the properties of thickness extension mode excited by lateral electric field on LiNbO3 by using the extended Christoffel-Bechmann method. It finds that the lateral field excitation coupling fac... This paper investigates the properties of thickness extension mode excited by lateral electric field on LiNbO3 by using the extended Christoffel-Bechmann method. It finds that the lateral field excitation coupling factor for amode (quasi-extensional mode) reaches its maximum value of 28% on Xmcut LiNbO3. The characteristics of a lateral field excitation device made of X-cut LiNbO3 have been investigated and the lateral field excitation device is used for the design of a high frequency ultrasonic transducer. The time and frequency domain pulse/echo response of the LiNbO3 lateral field excitation ultrasonic transducer is analysed with the modified Krimholtz-Leedom-Matthae model and tested using traditional pulse/echo method. A LiNbO3 lateral field excitation ultrasonic transducer with the centre frequency of 33.44 MHz and the -6 dB bandwidth of 33.8% is acquired, which is in good agreement with the results of the Krimholtz-Leedom-Matthae model. Further analysis suggests that the LiNbO3 lateral field excitation device has great potential in the design of broadband high frequency ultrasonic transducers. 展开更多
关键词 lateral field excitation high frequency ultrasonic transducer LiNb03 thickness extension mode
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Number of primitive elements of field extension GF(p^(nm))/GF(p^n)
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作者 严质彬 游宏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第1期56-58,共3页
Presents the counting of the counts number of primitive elements of finite dimensional field extension GF(p nm )/GF(p n) using (1) the principle of inclusion exclusion, (2) the Mbius inversion, (3) the Euler ... Presents the counting of the counts number of primitive elements of finite dimensional field extension GF(p nm )/GF(p n) using (1) the principle of inclusion exclusion, (2) the Mbius inversion, (3) the Euler  function, and the new identity obtained ∑t|p nm-1 , t p nmq j -1(t)=p nm -∑jp nmq j +∑j 1<j 2p nmqj 1qj 2 -…+(-1) kp nmq 1…q k  where, m>1, p is a prime, (·) is Euler function, and q 1,…,q k are the all distinct prime divisors of m. 展开更多
关键词 Euler function field extension the principle of inclusion exclusion Mbius inversion
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Study on the drain bias effect on negative bias temperature instability degradation of an ultra-short p-channel metal-oxide-semiconductor field-effect transistor
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作者 曹艳荣 马晓华 +1 位作者 郝跃 胡世刚 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期402-407,共6页
This paper studies the effect of drain bias on ultra-short p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET) degradation during negative bias temperature (NBT) stress. When a relatively large g... This paper studies the effect of drain bias on ultra-short p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET) degradation during negative bias temperature (NBT) stress. When a relatively large gate voltage is applied, the degradation magnitude is much more than the drain voltage which is the same as the gate voltage supplied, and the time exponent gets larger than that of the NBT instability (NBTI). With decreasing drain voltage, the degradation magnitude and the time exponent all get smaller. At some values of the drain voltage, the degradation magnitude is even smaller than that of NBTI, and when the drain voltage gets small enough, the exhibition of degradation becomes very similar to the NBTI degradation. When a relatively large drain voltage is applied, with decreasing gate voltage, the degradation magnitude gets smaller. However, the time exponent becomes larger. With the help of electric field simulation, this paper concludes that the degradation magnitude is determined by the vertical electric field of the oxide, the amount of hot holes generated by the strong channel lateral electric field at the gate/drain overlap region, and the time exponent is mainly controlled by localized damage caused by the lateral electric field of the oxide in the gate/drain overlap region where hot carriers are produced. 展开更多
关键词 negative bias temperature instability drain bias electric field localized damage
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Coherent control of negative refraction based on local-field enhancement and dynamically induced chirality
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作者 巴诺 高金伟 +2 位作者 田杏霞 吴熙 吴金辉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期284-291,共8页
This paper studies the electromagnetic response of a coherently driven dense atomic ensemble to a weak probe. It finds that negative refraction with little absorption may be achieved in the presence of local-field enh... This paper studies the electromagnetic response of a coherently driven dense atomic ensemble to a weak probe. It finds that negative refraction with little absorption may be achieved in the presence of local-field enhanced interaction and dynamically induced chirality. The complex refractive index governing the probe refraction and absorption depends critically on the atomic density, the steady population distribution, the coherence dephasings, and the frequency de- tunings, and is also sensitive to the phase of the driving field because the photonic transition paths form a close loop. Thus, it can periodically tune the refractive index at a fixed frequency from negative to positive values and vice versa just by modulating the driving phase. Moreover, the optimal negative refraction is found to be near the probe magnetic resonance, which then requires the electric fields of the probe and the drive being on two-photon resonance due to the dipole synchronisation. 展开更多
关键词 negative refraction dynamically induced chirality local field enhancement electromag-netically induced transparency
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High accuracy calculation of the hydrogen negative ion in strong magnetic fields
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作者 赵继军 王晓峰 乔豪学 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期222-226,共5页
Using a full configuration-interaction method with Hylleraas-Gaussian basis function, this paper investigates the 1^10^+, 1^1(-1)^+ and 1^1(-2)6+ states of the hydrogen negative ion in strong magnetic fields. T... Using a full configuration-interaction method with Hylleraas-Gaussian basis function, this paper investigates the 1^10^+, 1^1(-1)^+ and 1^1(-2)6+ states of the hydrogen negative ion in strong magnetic fields. The total energies, electron detachment energies and derivatives of the total energy with respect to the magnetic field are presented as functions of magnetic field over a wide range of field strengths. Compared with the available theoretical data, the accuracy for the energies is enhanced significantly. The field regimes 3 〈 γ 〈 4 and 0.02 〈 γ 〈 0.05, in which the 1^1(-1)6+ and 1^1(-2)^+ states start to become bound, respectively, are also determined based on the calculated electron detachment energies. 展开更多
关键词 strong magnetic field hydrogen negative ion total energy electron detachment energy
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Electric Potential in Surface Produced Negative Ion Source with Magnetic Field Increasing Toward a Wall
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作者 Azusa FUKANO Akiyoshi HATAYAMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第3期266-270,共5页
Electric potential near a wall for plasma with the surface produced negative ions with magnetic field increasing toward a wall is investigated analytically. The potential profile is derived analytically by using a pla... Electric potential near a wall for plasma with the surface produced negative ions with magnetic field increasing toward a wall is investigated analytically. The potential profile is derived analytically by using a plasma-sheath equation, where negative ions produced on the plasma grid (PG) surface are considered in addition to positive ions and electrons. The potential profile depends on the amount and the temperature of the surface produced negative ions and the profile of the magnetic field. The negative potential peak is formed in the sheath region near the PG surface for the case of strong surface production of negative ions or low temperature negative ions. As the increase rate of the magnetic field near the wall becomes large, the negative potential peak becomes small. 展开更多
关键词 negative ion source surface produced negative ion sheath potential cusp magnetic field electric potential plasma-sheath equation extraction region
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The Influence of the Negative Radial Electric Field on the Orbit of Banana Particles in Tokamak
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作者 刘玉文 张晓东 +1 位作者 张韬 姚若河 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2801-2804,共4页
This paper explores the patterns of influence of the negative radial electric field on the drift displacement and trajectory of charged particles, for it is essential for further investigation into the transitional me... This paper explores the patterns of influence of the negative radial electric field on the drift displacement and trajectory of charged particles, for it is essential for further investigation into the transitional mechanism of L-H Mode. In the light of superposition between the poloidal velocity of charged particles and the E × B drift caused by the negative radial electric field, the paper offers a theoretical analysis and value simulations. Under the action of different radial electric fields, results have been obtained in regard to changes in the velocity of charged particles (mainly ions), patterns of changes in drift displacement, regional change of banana particles, and features of transition and change between trajectories of transiting particles and banana particles. 展开更多
关键词 negative electric field drift displacement E × B drift numerical simulation
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Time evolution of negative binomial optical field in a diffusion channel
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作者 刘堂昆 吴盼盼 +2 位作者 单传家 刘继兵 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期97-100,共4页
We find the time evolution law of a negative binomial optical field in a diffusion channel. We reveal that by adjusting the diffusion parameter, the photon number can be controlled. Therefore, the diffusion process ca... We find the time evolution law of a negative binomial optical field in a diffusion channel. We reveal that by adjusting the diffusion parameter, the photon number can be controlled. Therefore, the diffusion process can be considered a quantum controlling scheme through photon addition. 展开更多
关键词 negative binomial optical field time evolution diffusion channel integration within an ordered product(IWOP) of operators
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Negative Magnetoresistance Behaviour and Variable Range Hopping Conduction in Insulating NbSi Amorphous Alloys at Very Low Temperature with aagnetic Field
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作者 Abdelghani Sybous Abdelhamid El Kaaouachi +5 位作者 Jamal Hemine Abdelfattah Narjis Lhoussine Limouny Said Dlimi Rachid Abdia Gerard Biskupski 《Journal of Modern Physics》 2012年第7期521-528,共8页
We present results of an experimental study of magnetoresistance (MR) in insulating NbSi amorphous alloys sample showing Variable Range Hopping (VRH) conductivity. The MR is found to be negative in a wide range of low... We present results of an experimental study of magnetoresistance (MR) in insulating NbSi amorphous alloys sample showing Variable Range Hopping (VRH) conductivity. The MR is found to be negative in a wide range of low temperature (4.2-20 K) and in the range of moderate magnetic fields (0-4 T). We made tentative analysis using three theoretical models which are the model of quantum interference, the model of Zeeman effect and the model of localized magnetic 展开更多
关键词 NbSi Amorphous Alloys negative MAGNETORESISTANCE MAGNETIC field LOCALIZED MAGNETIC MOMENTS Quantum Interference
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Assessment of rice fields by GIS/GPS-supported classification of MODIS data 被引量:3
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作者 程乾 黄敬峰 王人潮 《Journal of Zhejiang University Science》 EI CSCD 2004年第4期412-417,共6页
The new Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite image offers a large choice of opportunities for operational applications. The 1-km Advanced Very High Resolution Radiometer (AVHRR) image is not... The new Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite image offers a large choice of opportunities for operational applications. The 1-km Advanced Very High Resolution Radiometer (AVHRR) image is not suitable for retrieval of field level parameter and Landsat data are not frequent enough for monitoring changes in crop parameters during the critical crop growth periods.A methodology to map areas of paddy fields using MODIS,geographic information system (GIS) and global position system (GPS) is introduced in this paper. Training samples are selected and located with the help of GPS to provide maximal accuracy.A concept of assessing areas of potential cultivation of rice is suggested by means of GIS integration. By integration of MODIS with GIS and GPS technologies the actual areas of rice fields in 2002 have been mapped. The classification accuracy was 95.7% percent compared with the statistical data of the Agricultural Bureau of Zhejiang Province. 展开更多
关键词 Areas of rice fields Moderate-Resolution Imaging Spectroradiometer (MODIS) Geographic information system (GIS) Global position system (GPS)
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p-Capitulation over Number Fields with p-Class Rank Two 被引量:2
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作者 Daniel C. Mayer 《Journal of Applied Mathematics and Physics》 2016年第7期1280-1293,共14页
Theoretical foundations of a new algorithm for determining the p-capitulation type ù(K) of a number field K with p-class rank ?=2 are presented. Since ù(K) alone is insufficient for identifying the seco... Theoretical foundations of a new algorithm for determining the p-capitulation type ù(K) of a number field K with p-class rank ?=2 are presented. Since ù(K) alone is insufficient for identifying the second p-class group  G=Gal(F<sub>p</sub><sup>2</sup>K∣K) of K, complementary techniques are deve- loped for finding the nilpotency class and coclass of . An implementation of the complete algorithm in the computational algebra system Magma is employed for calculating the Artin pattern  AP(K)=(τ (K),ù(K)) of all 34631 real quadratic fields K=Q(√d) with discriminants  0d<10<sup>8</sup> and 3-class group of type (3, 3). The results admit extensive statistics of the second 3-class groups G=Gal(F<sub>3</sub><sup>2</sup>K∣K) and the 3-class field tower groups G=Gal(F<sub>3</sub><sup>∞</sup>K∣K). 展开更多
关键词 Hilbert p-Class field Tower Maximal Unramified Pro-p extension p-Capitulation of Class Groups Real Quadratic fields (3 3)
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Entanglement properties between two atoms in the binomial optical field interacting with two entangled atoms 被引量:1
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作者 刘堂昆 张康隆 +2 位作者 陶宇 单传家 刘继兵 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期138-144,共7页
The temporal evolution of the degree of entanglement between two atoms in a system of the binomial optical field interacting with two arbitrary entangled atoms is investigated. The influence of the strength of the dip... The temporal evolution of the degree of entanglement between two atoms in a system of the binomial optical field interacting with two arbitrary entangled atoms is investigated. The influence of the strength of the dipole–dipole interaction between two atoms, probabilities of the Bernoulli trial, and particle number of the binomial optical field on the temporal evolution of the atomic entanglement are discussed. The result shows that the two atoms are always in the entanglement state. Moreover, if and only if the two atoms are initially in the maximally entangled state, the entanglement evolution is not affected by the parameters, and the degree of entanglement is always kept as 1. 展开更多
关键词 quantum optics quantum entanglement binomial optical field negative eigenvalue
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