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Characterizations of semihoops based on derivations
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作者 WANG Mei ZHANG Xiao-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期291-310,共20页
In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multipli... In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative derivations.Finally,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence. 展开更多
关键词 (prelinear)semihoop derivation Heyting algebra Galois connection
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Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis
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作者 Xiahong Tang Nan Zheng +8 位作者 Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1103-1123,共21页
Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to impr... Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning. 展开更多
关键词 bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria NEUROINFLAMMATION oxidative stress PYROPTOSIS reactive oxygen species
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Concept Derivation in the Conceptual Planning of Jiuzhouwa Eco-Wetland Park
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作者 翟付顺 吕瑞霞 刘玮 《Journal of Landscape Research》 2010年第4期12-14,共3页
Through analyzing problems exist in the conceptual planning of Jiuzhouwa Eco-Wetland Park, the derivation process and approach of its core concepts were discussed.
关键词 Jiuzhouwa Eco-Wetland Park Conceptual Planning CONCEPT derivation
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DERIVATION ALGEBRAS OF THE MODULAR LIE SUPERALGEBRAS W AND S OF CARTAN-TYPE 被引量:32
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作者 张庆成 张永正 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期137-144,共8页
Let F be a field and char F = p > 3. In this paper the derivation algebras of Lie superalgebras W and S of Cartan-type over F are determined by the calculating method.
关键词 Lie superalgebra exterior algebra derivation algebra
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Design of PID controller with incomplete derivation based on differential evolution algorithm 被引量:16
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作者 Wu Lianghong Wang Yaonan +1 位作者 Zhou Shaowu Tan Wen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期578-583,共6页
To determine the optimal or near optimal parameters of PID controller with incomplete derivation, a novel design method based on differential evolution (DE) algorithm is presented. The controller is called DE-PID co... To determine the optimal or near optimal parameters of PID controller with incomplete derivation, a novel design method based on differential evolution (DE) algorithm is presented. The controller is called DE-PID controller. To overcome the disadvantages of the integral performance criteria in the frequency domain such as IAE, ISE, and ITSE, a new performance criterion in the time domain is proposed. The optimization procedures employing the DE algorithm to search the optimal or near optimal PID controller parameters of a control system are demonstrated in detail. Three typical control systems are chosen to test and evaluate the adaptation and robustness of the proposed DE-PID controller. The simulation results show that the proposed approach has superior features of easy implementation, stable convergence characteristic, and good computational efficiency. Compared with the ZN, GA, and ASA, the proposed design method is indeed more efficient and robust in improving the step response of a control system. 展开更多
关键词 PID controller incomplete derivation differential evolution parameter tuning.
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DERIVATIONS AND EXTENSIONS OF LIE COLOR ALGEBRA 被引量:5
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作者 张庆成 张永正 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期933-948,共16页
In this article,the authors obtain some results concerning derivations of finitely generated Lie color algebras and discuss the relation between skew derivation space SkDer(L)and central extension H^2(L,F)on some ... In this article,the authors obtain some results concerning derivations of finitely generated Lie color algebras and discuss the relation between skew derivation space SkDer(L)and central extension H^2(L,F)on some Lie color algebras.Meanwhile,they generalize the notion of double extension to quadratic Lie color algebras,a sufficient condition for a quadratic Lie color algebra to be a double extension and further properties are given. 展开更多
关键词 derivation central extension double extension quadratic Lie color algebra
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Design of PID controller with incomplete derivation based on ant system algorithm 被引量:6
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作者 Guanzheng TAN Qingdong ZENG Wenbin LI 《控制理论与应用(英文版)》 EI 2004年第3期246-252,共7页
A new and intelligent design method for PID controller with incomplete derivation is proposed based on the ant system algorithm ( ASA) . For a given control system with this kind of PID controller, a group of optimal ... A new and intelligent design method for PID controller with incomplete derivation is proposed based on the ant system algorithm ( ASA) . For a given control system with this kind of PID controller, a group of optimal PID controller parameters K p * , T i * , and T d * can be obtained by taking the overshoot, settling time, and steady-state error of the system's unit step response as the performance indexes and by use of our improved ant system algorithm. K p * , T i * , and T d * can be used in real-time control. This kind of controller is called the ASA-PID controller with incomplete derivation. To verify the performance of the ASA-PID controller, three different typical transfer functions were tested, and three existing typical tuning methods of PID controller parameters, including the Ziegler-Nichols method (ZN),the genetic algorithm (GA),and the simulated annealing (SA), were adopted for comparison. The simulation results showed that the ASA-PID controller can be used to control different objects and has better performance compared with the ZN-PID and GA-PID controllers, and comparable performance compared with the SA-PID controller. 展开更多
关键词 PID controller Incomplete derivation Parameter tuning Ant system algorithm Genetic algorithm Simulated annealing
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APPLICATION OF PARAMETRIC DERIVATION METHOD TO THE CALCULATION OF PEIERLS ENERGY AND PEIERLS STRESS IN LATTICE THEORY 被引量:4
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作者 Xiaozhi Wu Shaofeng Wang 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第4期363-368,共6页
Applying the parametric derivation method, Peierls energy and Peierls stress are calculated with a non-sinusoidal force law in the lattice theory, while the results obtained by the power-series expansion according to ... Applying the parametric derivation method, Peierls energy and Peierls stress are calculated with a non-sinusoidal force law in the lattice theory, while the results obtained by the power-series expansion according to sinusoidal law can be deduced as a limiting case of non- sinusoidal law. The simplified expressions of Peierls energy and Peierls stress are obtained for the limit of wide and narrow. Peierls energy and Peierls stress decrease monotonically with the factor of modification of force law. Present results can be used expediently for prediction of the correct order of magnitude of Peierls stress for materials. 展开更多
关键词 Peierls energy Peierls stress parametric derivation method lattice theory
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Analysis of the monosaccharide composition of fucoidan by precolumn derivation HPLC 被引量:6
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作者 张晶晶 张全斌 +2 位作者 王晶 石学连 张忠山 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期578-582,共5页
We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the m... We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaecharide derivatives, obtained with 1-Phenyl-3-methyl-5- pyrazolone (PMP), were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration (r^2〉0.998). The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans. 展开更多
关键词 FUCOIDAN MONOSACCHARIDE derivation HPLC
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Nonlinear Jordan Higher Derivations of Triangular Algebras 被引量:4
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作者 Fu Wen-lian Xiao Zhan-kui Du Xian-kun 《Communications in Mathematical Research》 CSCD 2015年第2期119-130,共12页
In this paper, we prove that any nonlinear Jordan higher derivation on triangular algebras is an additive higher derivation. As a byproduct, we obtain that any nonlinear Jordan derivation on nest algebras over infinit... In this paper, we prove that any nonlinear Jordan higher derivation on triangular algebras is an additive higher derivation. As a byproduct, we obtain that any nonlinear Jordan derivation on nest algebras over infinite dimensional Hilbert suaces is inner. 展开更多
关键词 nonlinear Jordan higher derivation triangular algebra nest algebra
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Fuzzy-GA PID controller with incomplete derivation and its application to intelligent bionic artificial leg 被引量:8
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作者 谭冠政 李安平 《Journal of Central South University of Technology》 2003年第3期237-243,共7页
An optimal PID controller with incomplete derivation is proposed based on fuzzy inference and the geneticalgorithm, which is called the fuzzy-GA PID controller with incomplete derivation. It consists of the off-line p... An optimal PID controller with incomplete derivation is proposed based on fuzzy inference and the geneticalgorithm, which is called the fuzzy-GA PID controller with incomplete derivation. It consists of the off-line part andthe on-line part. In the off-line part, by taking the overshoot, rise time, and settling time of system unit step re-sponse as the performance indexes and by using the genetic algorithm, a group of optimal PID parameters K*p , Ti* ,and Tj are obtained, which are used as the initial values for the on-line tuning of PID parameters. In the on-linepart, based on K; , Ti* , and T*d and according to the current system error e and its time derivative, a dedicatedprogram is written, which is used to optimize and adjust the PID parameters on line through a fuzzy inference mech-anism to ensure that the system response has optimal dynamic and steady-state performance. The controller has beenused to control the D. C. motor of the intelligent bionic artificial leg designed by the authors. The result of computersimulation shows that this kind of optimal PID controller has excellent control performance and robust performance. 展开更多
关键词 fuzzy inference genetic algorithm fuzzy-GA PID controller INCOMPLETE derivation OFF-LINE on-line INTELLIGENT BIONIC artificial LEG
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DERIVATION AND INTEGRAL SLIDING MODE VARIABLE STRUCTURE CONTROL OF HYDRAULIC VELOCITY TRACKING SYSTEM 被引量:3
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作者 WeiJianhua GuanCheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期224-227,共4页
The velocity tracking control of a hydraulic servo system is studied. Sincethe dynamics of the system are highly nonlinear and have large extent of model uncertainties, suchas big changes in load and parameters, a der... The velocity tracking control of a hydraulic servo system is studied. Sincethe dynamics of the system are highly nonlinear and have large extent of model uncertainties, suchas big changes in load and parameters, a derivation and integral sliding mode variable structurecontrol scheme (DI-SVSC) is proposed. An integral controller is introduced to avoid the assumptionthat the derivative of desired signal must be known in conventional sliding mode variable structurecontrol, a nonlinear derivation controller is used to weaken the chattering of system. The designmethod of switching function in integral sliding mode control, nonlinear derivation coefficient andcontrollers of DI-SVSC is presented respectively. Simulation shows that the control approach is ofnice robustness and improves velocity tracking accuracy considerably. 展开更多
关键词 Hydraulic servo system Velocity tracking Integral variable structurecontrol Nonlinear derivation control
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Certain Pair of Derivations on a Triangular Algebra 被引量:2
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作者 GUO YING LI XIA +1 位作者 MA JING Du Xian-kun 《Communications in Mathematical Research》 CSCD 2014年第3期265-272,共8页
By using properties of triangular algebra, we prove that if derivations D and G on a triangular algebra T satisfy certain generalized identities, then both D and G are zero mappings. As a corollary we get that if D an... By using properties of triangular algebra, we prove that if derivations D and G on a triangular algebra T satisfy certain generalized identities, then both D and G are zero mappings. As a corollary we get that if D and G are cocentralizing on T, then both D and G are zero mappings. 展开更多
关键词 triangular algebra derivation cocentralizing the Engel condition
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The Linear Combination of Derivations in Prime Rings 被引量:5
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作者 王宇 张秀英 《Northeastern Mathematical Journal》 CSCD 2002年第4期298-302,共5页
In this paper we discuss the linear combination of derivations in prime rings which was initiated by Niu Fengwen. Our aim is to improve Niu's result. For the proof of the main theorem we generalize a result of Bre... In this paper we discuss the linear combination of derivations in prime rings which was initiated by Niu Fengwen. Our aim is to improve Niu's result. For the proof of the main theorem we generalize a result of Bresar and obtain a lemma that is of independent interest. 展开更多
关键词 derivation prime ring extended centroid
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GENERALIZED DERIVATIONS ON PARABOLIC SUBALGEBRAS OF GENERAL LINEAR LIE ALGEBRAS 被引量:1
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作者 陈正新 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期814-828,共15页
Let P be a parabolic subalgebra of a general linear Lie algebra gl(n,F) over a field F, where n ≥ 3, F contains at least n different elements, and char(F) ≠ 2. In this article, we prove that generalized derivati... Let P be a parabolic subalgebra of a general linear Lie algebra gl(n,F) over a field F, where n ≥ 3, F contains at least n different elements, and char(F) ≠ 2. In this article, we prove that generalized derivations, quasiderivations, and product zero derivations of P coincide, and any generalized derivation of P is a sum of an inner derivation, a central quasiderivation, and a scalar multiplication map of P. We also show that any commuting automorphism of P is a central automorphism, and any commuting derivation of P is a central derivation. 展开更多
关键词 Parabolic subalgebras general linear Lie algebras generalized derivations quasiderivations product zero derivations
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A Matrix Representation of Outer Derivations from gl0|2 to the Generalized Witt Lie Superalgebra 被引量:1
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作者 ZHENG KE-LI Du Xian-kun 《Communications in Mathematical Research》 CSCD 2019年第4期367-376,共10页
Let gl0|2 be a subalgebra of the general linear Lie superalgebra.In this paper,outer derivations from gl0|2 to the generalized Witt Lie superalgebra are completely determined by matrices.
关键词 outer derivation INNER derivation matrix representation generalized Witt LIE SUPERALGEBRA
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Determination of sulfur anions by ion chromatography-postcolumn derivation and UV detection 被引量:2
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作者 Mei Lan Chen Ming Li Ye +2 位作者 Xue Ling Zeng Yun Chang Fan Zhu Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1241-1244,共4页
A novel method for determination of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate in foodstuffs by ion chromatography separation with postcolumn derivation and UV detection has been developed. All sp... A novel method for determination of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate in foodstuffs by ion chromatography separation with postcolumn derivation and UV detection has been developed. All species are separated at Dionex IonPac AG22A and AS22A with mobile phase of a mixture of 4.5 mmol/L sodium carbonate and 0.8 mmol/L sodium bicarbonate at a flow-rate of 1.0 mL/min. The postcolunm derivation solution was 0.24% iodine in 0.2% phosphate acid and the detection wavelength was set at 288 nm. The detection limits (LOD, signal-to-noise ratio of 3) of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate were 0.004, 0.006, 0.006, and 0.007 mg/L, respectively. Within-day relative standard deviations (RSD, n = 10) of formaldehyde sulfoxylate, sulflte, thiocyanate, and thiosulfate were 3.24%, 3.76%, 2.68%, and 2.07%, respectively. The recoveries of the four anions were in the range of 67.2-116.5%. 展开更多
关键词 Postcolumn derivation Ion chromatography Sulfur-containing inorganic compounds
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STABILITY OF GENERALIZED DERIVATIONS ON HILBERT C*-MODULES ASSOCIATED WITH A PEXIDERIZED CAUCHY-JENSEN TYPE FUNCTIONAL EQUATION 被引量:2
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作者 Ali Ebadian Ismail Nikoufar +1 位作者 Themistocles M.Rassias Norouz Ghobadipour 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1226-1238,共13页
In this article, we introduce the notion of generalized derivations on Hilbert C*-modules. We use a fixed-point method to prove the generalized Hyers-Ulam-Rassias stability associated to the Pexiderized Cauchy-Jensen... In this article, we introduce the notion of generalized derivations on Hilbert C*-modules. We use a fixed-point method to prove the generalized Hyers-Ulam-Rassias stability associated to the Pexiderized Cauchy-Jensen type functional equationrf(x+y/r)+sg(x-y/s)=2h(x)for r, s ∈ R / {0} on Hilbert C*-modules, where f, g, and h are mappings from a Hilbert C*-module M to M. 展开更多
关键词 Hyers-Ulam-Rassias stability Hilbert C*-module generalized derivation fixed point
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Lie Higher Derivations on Nest Algebras 被引量:1
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作者 QI XIAO-FEIi Hou JIN-CHUAN 《Communications in Mathematical Research》 CSCD 2010年第2期131-143,共13页
Let N be a nest on a Banach space X, and Alg N be the associated nest algebra. It is shown that if there exists a non-trivial element in N which is complemented in X, then D = (Ln)n∈N is a Lie higher derivation of ... Let N be a nest on a Banach space X, and Alg N be the associated nest algebra. It is shown that if there exists a non-trivial element in N which is complemented in X, then D = (Ln)n∈N is a Lie higher derivation of AlgAl if and only if each Ln has the form Ln(A) : Tn(A) + hn(A)I for all A ∈ AlgN, where (Tn)n∈N is a higher derivation and (hn)n∈N is a sequence of additive functionals satisfying hn([A,B]) = 0 for all A,B ∈ AlgN and all n ∈ N. 展开更多
关键词 nest algebra higher derivation Lie higher derivation
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Derivation of baroclinic Ertel–Rossby invariant-based thermally-coupled vorticity equation in moist flow 被引量:1
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作者 杨帅 高守亭 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期700-705,共6页
For the potential vorticity (PV) invariant, there is a PV-based complete-form vorticity equation, which we use heuris- tically in the present paper to answer the following question: for the Ertel-Rossby invariant ... For the potential vorticity (PV) invariant, there is a PV-based complete-form vorticity equation, which we use heuris- tically in the present paper to answer the following question: for the Ertel-Rossby invariant (ERI), is there a corresponding vorticity tendency equation? Such an ERI-based thermally-coupled vorticity equation is derived and discussed in detail in this study. From the obtained new vorticity equation, the vertical vorticity change is constrained by the vertical velocity term, the term associated with the slope of the generalized momentum surface, the term related to the horizontal vorticity change, and the baroclinic or solenoid term. It explicitly includes both the dynamical and thermodynamic factors' influence on the vorticity change. For the ERI itself, besides the traditional PV term, the ERI also includes the moisture factor, which is excluded in dry ERI, and the term related to the gradients of pressure, kinetic energy, and potential energy that reflects the fast-manifold property. Therefore, it is more complete to describe the fast motions off the slow manifold for severe weather than the PV term. These advantages are naturally handed on and inherited by the ERI-based thermally-coupled vorticity equation. Then the ERI-based thermally-coupled vorticity equation is further transformed and compared with the traditional vorticity equation. The main difference between the two equations is the term which describes the contribution of the solenoid term to the vertical vorticity development. In a barotropic flow, the solenoid term disappears, then the ERI-based thermally-coupled vorticity equation can regress to the traditional vorticity equation. 展开更多
关键词 vorticity equation derivation Ertel-Rossby invariant
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