共查询到20条相似文献,搜索用时 15 毫秒
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Minoru Morikawa 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1962,13(2):167-175
Zusammenfassung Die Fokussierungseigenschaften eines aus schwachen Linsen bestehenden Systems unterhalb eines Beschleunigungsrohres sind studiert worden. Das System wird als dicke Linse in der Näherung der paraxialen Bahn behandelt. Die Kardinalelemente des Linsensystems können als Ganzes für den Fall, dass das Feld periodisch ist, in einfacher Form dargestellt werden.Im besondern sind die Ausdrücke für die Kardinalelemente eines Systems, das aus den Zweirohr-Immersionslinsen mit bestimmter Länge der Lücke zwischen den Rohren besteht, wiedergegeben. Die beigefügten Figuren erlauben, diese Elemente bequem zu berechnen. 相似文献
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《European Journal of Operational Research》1999,112(2):284-303
A multi-stage production line which operates under a just-in-time production philosophy with linear demand is considered here. The first workstation processes the raw materials after receiving them from suppliers, a kanban mechanism between the workstations transports the work-in-process to the succeeding workstation, and after processing them, delivers the finished products to a buyer or a warehouse. The problem is to find optimally the number of raw material orders, kanbans circulated between workstations, finished goods shipments to the buyers, and the batch size for each shipment (lot). A cost function is developed based on the costs incurred due to the raw materials, the work-in-process between workstations, and the finished goods. Optimal number of raw material orders that minimizes the total cost is obtained, which is then used to find the optimal number of kanbans, finished goods shipments, and the batch sizes for shipments. Numerical examples are used to demonstrate the computations of optimal parameters, and to configure the kanban mechanism on a timescale. Several avenues for future research are also indicated. 相似文献
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This paper presents exact solutions in terms of implicit functions and hyperbolic functions to a nonconvex dissipative system, controlled by a Duffing–van der Pol nonlinear equation with a fifth-order nonlinearity. Applications to the complex Ginzburg–Landau equation are illustrated and several classes of uniformly translating solutions are obtained accordingly. Part of the work was announced at the International Conference on Complementarity, Duality, and Global Optimization in Science and Engineering, Virginia Tech. University, Blacksburg, Virginia, August 15–17, 2005. This work is supported by NSF Grant CCF–0514768. 相似文献
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In a production system, rework process plays an important role in eliminating waste and effectively controlling the cost of manufacturing. Determining the optimal batch size in a system that allows for rework is, therefore, a worthwhile objective to minimize the inventory cost of work-in-processes and the finished goods. In this paper, models for the optimum batch quantity in a multi-stage system with rework process have been developed for two different operational policies. Policy 1 deals with the rework within the same cycle with no shortage and policy 2 deals with the rework done after N cycles, incurring shortages in each cycle. The major components that play a role in minimizing this cost of the system are manufacturing setups, work-in-processes, storage of finished goods, rework processing, waiting-time, and penalty costs to discourage the generation of defectives. The mathematical structure of this rework processing model falls under a nonlinear convex programming problems for which a closed-form solution has been proposed and results are demonstrated through numerical examples, followed by sensitivity analyses of different important parameters. It is concluded that the total cost in policy 2 tends to be smaller than that in policy 1 at lower proportion of defectives if the in-process carrying cost is low. Policy 2 may be preferred when the work-in-process carrying cost is low and the penalty cost is negligible. 相似文献
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The paper solves analytically the Riemann problem for a nonstrictly hyperbolic system of conservation laws arising in geometrical optics,in which the flux contains the nonconvex function possessing an infinite number of inflection points.Firstly,the generalized Rankine–Hugoniot relations and entropy condition of delta shock waves and left(right)-contact delta shock waves are proposed and clarified.Secondly,with the help of the convex hull,seven kinds of structures of Riemann solutions are obtained.The solutions fall into three broad categories with a series of geometric structures involving simultaneously contact discontinuities,vacuums and delta shock waves.Finally,numerical experiments confirm the theoretical analysis. 相似文献
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Recently, Sarker et al. [Sarker, B.R., Jamal, A.M.M., Mondal, S., 2008. Optimal batch sizing in a multi-stage production system with rework consideration. European Journal of Operational Research 184(3) 915–929] presented an EPQ inventory model for a multi-stage manufacturing system with rework process; basically they proposed two operational inventory policies. In the paper, there are some mathematical expressions which are to be corrected. At first, this paper presents the mathematical expressions corrected and the appropriate solution to the numerical example. We also established the closed forms for the optimal total inventory cost, the conditions for which there is an optimal solution, and the mathematical expressions for determining the total additional cost for working with a non optimal solution for both policies that were not given by Sarker et al. (2008). 相似文献
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Yu Yanlin 《数学学报(英文版)》1990,6(1):80-86
This paper considers geodesic triangies in a Riemannian manifoldM. First we imbed the set of geodesic triangles inM into a big spaceE, then find some equations inE satisfied by tangent vectors of . Finally we give an application of the result. 相似文献
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V. P. Karasev 《Theoretical and Mathematical Physics》1993,95(1):367-377
It is shown that specific (polynomial) deformations of Lie algebras arise naturally as dynamical symmetry algebrasg
ds of second-quantized models with nonquadratic HamiltoniansH invariant with respect to certain groupsG
inv(H). Such deformationssl
d(2) of the Lie algebrasl(2) are found in a number of models of quantum optics (multiphoton processes, generalized Dicke model, and frequency conversion), and ways to apply thesl(2) formalism to the solution of physics problems are indicated.P. N. Lebedev Physics Institute, Russian Academy of Sciences. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 95, No. 1, pp. 3–19, April, 1993. 相似文献
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Preparation and structural characterization of palladium (II) complexes of ligands III-V and copper (II) complexes of III are reported. The elemental analyses of the complexes show that the metal: ligand ratio is 1:2. The electrical conductance in acetone shows the non-electrolytic nature of the complexes. The diamagnetic character suggests a gross square-planar geometry for the palladium (II) complexes. Copper (II) complexes are paramagnetic with¼eff.~1·90 B.M. Spectral data suggest that in all the complexes the ligand coordinates to the metal (II) symmetrically through isonitroso-nitrogen and imine-nitrogen, forming a five membered chelate ring. Amine-exchange reactions of the complexes are discussed and compared on the basis of their structures. 相似文献
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《Nonlinear Analysis: Real World Applications》2008,9(3):1068-1077
Considering the abrupt jump of the substrate and different characters of the bacterial in the lag phase, the exponential phase and the stationary phase this paper proposes the multi-stage nonlinear impulsive system for the fed-batch fermentation from glycerol to 1,3-propanediol (1,3-PD) and establishes the bilevel identification system for its sensitive parameters. The properties of the solutions for the nonlinear multi-stage dynamical system are investigated and identifiability of the parameters is proved. Finally an optimal algorithm is constructed to obtain the optimal solution of the identification model and the numerical example is then discussed to illustrate the algorithm. 相似文献
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Coordination compounds of Cu (II), Ni (II) and Co (II) with sulphamethazine salicylaldimine (an antitubercular) have been
prepared with a view to study their antibacterial activity. These complexes are granular, stable and are quantitatively formed
and characterised by elemental analysis. Structures have been assigned based on their infrared, electronic absorption spectral
and magnetic susceptibility studies. The antibacterial activity was tested against eleven available pathogens and in some
cases complexes are found to be more potent. 相似文献
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Xu Yonghua 《数学年刊B辑(英文版)》1980,1(34):399-409
Denote R an associative ring,\[\mathcal{M}\] a right modular idea of R,i,e,there exists an \[a \in R\] such that for all \[r \in R\],\[r + ar \in \mathcal{M}\],
Let \[\{ {\mathcal{M}_i}\} \] be a given set of modular right ideals of R.Then introduce the following definition:
Definition 1.Let \[\mathcal{M}\] be a modular right ideals of R. An element a of \[\mathcal{M}\] is called an \[\mathcal{M}\]-right quasi-regular element,if{i+ai}=\[\mathcal{M}\] for all \[i \in \mathcal{M}\].A right ideal L of R is called \[i \in \mathcal{M}\]-regular right ideal if every element of L is an \[i \in \mathcal{M}\]-right quasiregular element.
Definition 2. Let \[i \in \mathcal{M}\] and \[{\mathcal{M}^'}\] be two right ideals of R,\[{\mathcal{M}^'}\] is called \[{\mathcal{M}^'}\]-modular if \[{\mathcal{M}^'} \subset \mathcal{M}\] and if there exist an element \[a \in \mathcal{M}\] such that for all \[i \in \mathcal{M}\],\[i + ai \in {\mathcal{M}^'}\].
Now we introduce the symbol \[{\hat \mathcal{M}}\].Let \[\mathcal{M} \in \sum \].Then if \[\mathcal{M}\] is an \[\mathcal{M}\]-regular right ideal,we put \[\hat \mathcal{M} = \mathcal{M}\];if \[\mathcal{M}\] is not an \[\mathcal{M}\]-regular ideal,we put \[{\hat \mathcal{M}}\] to be an \[\mathcal{M}\]-maximal modular right ideal in \[\mathcal{M}\].Let \[\mathcal{M} \in \sum \].Then if \[\mathcal{M}\] is not an \[\mathcal{M}\]-regular right ideal,we put \[\hat \mathcal{M} = \mathcal{M} \in {{\hat \sum }_\mathcal{M}} = \{ \hat \mathcal{M}|\hat \mathcal{M} is \mathcal{M}\} \]-maximal modular right ideal};if \[\mathcal{M}\] is an \[\mathcal{M}\]-right regular right idal,we put \[{{\hat \sum }_\mathcal{M}} = \mathcal{M}\].
Now we put
\[\hat \sum = \{ \hat \mathcal{M}|\hat \mathcal{M} \in {{\hat \sum }_\mathcal{M}},\mathcal{M} \in \sum \} \]
and \[\hat J = \cup {L_i}\] (1)
for an element \[\mathcal{M} \in \sum \],where \[{L_i}\] are \[\mathcal{M}\]-regular right ideal,and U is set theoretical sum.Furthermore we put
\[\hat J = \mathop \cap \limits_{\mathcal{M} \in \sum } {{\hat J}_\mathcal{M}}\] (2)
and
\[{J_1} = \{ b|b \in \mathop \cap \limits_{\mathcal{M} \in \sum } \mathcal{M},\],b satisfying the following condition}, (3)
i,e,if |b)+\[{\mathcal{M}^{{\text{1}}}}{\text{ = }}\mathcal{M} \in \sum \] for an \[\mathcal{M}\]-modular right ideal \[{\mathcal{M}^{{\text{1}}}}\],then it must be \[{\mathcal{M}^{{\text{1}}}}{\text{ = }}\mathcal{M}\],where |b) is the intersection of all right ideals including b.
Definition 3.an element \[\mathcal{M}\] of \[\sum \] is called satisfying J1-left idealizer condition,if \[x \in {J_1},y \in \mathcal{M}\],then \[rx + ryx \in \mathcal{M}\] for all \[r \in R\].The \[\sum \] is called satisfying J1-left idealizer condition(briefly,J1-l,i,c) if every \[\mathcal{M}\] \[\mathcal{M}\] of \[\sum \] is satisfying J1-l,i.c.
Theorem 1. Suppose that \[\sum = \{ \mathcal{M}\} \] is satisfying J1-l.i.c.and put \[\beta = \hat \mathcal{M}\];\[R = \{ x \in R|Rx \subset \hat \mathcal{M}\} ,\hat \mathcal{M} \in \hat \sum \],then J1 is an ideal and \[{J_1} = \hat J = \sum\limits_{\hat \mathcal{M} \in \hat \sum } {\hat \mathcal{M} = \mathop \cap \limits_{\hat \mathcal{M} \in \hat \sum } } \beta \]
Definition 4. Let \[\sum = \{ \mathcal{M}\} \] be satisfying J1-l.i.c.\[\hat \sum = \{ \hat \mathcal{M}|\hat \mathcal{M} \in {{\hat \sum }_\mathcal{M}},\mathcal{M} \in \sum \} \] as stated in (1), then we call ideal \[{J_1} = \mathop \cup \limits_{\hat \mathcal{M} \in \hat \sum } \hat \mathcal{M}\] the \[\sum \]-radioal of R. If J1=0, then R is called \[\sum \]-semisimple ring.
Theorem 2. Let \[\sum = \{ \mathcal{M}\} \] be satisfying J1-'.i.c,where J1 is \[\sum \]-radical of R}, and
\[\bar \sum = \{ \bar \mathcal{M}\} ,\bar \mathcal{M} = \mathcal{M}/{J_1},\mathcal{M} \in \sum ,\bar \hat \sum = \{ \bar \hat \mathcal{M}\} ,\hat \mathcal{M} \in \hat \sum ,\bar \hat \mathcal{M} = \hat \mathcal{M}/{J_1}\] then the \[{\bar \sum }\]-radical of \[\bar R = R/{J_1}\] is \[{\bar 0}\].
Definition 5. Let \[\sum = \{ \mathcal{M}\} \] be satisfying J1-l.i.c. and \[\hat \sum = \{ \hat \mathcal{M}\} \], then R is called a
basic ring if and only if there exists an element \[{\hat \mathcal{M}}\] of such that \[\hat \mathcal{M}:R = 0\]. Let \[\beta \] be an ideal
of R, if \[\beta = \hat \mathcal{M}\]\[:R\], \[\hat \mathcal{M} \in \hat \sum \],then \[\beta \] is called a basic ideal of R.
Theorem 3. The \[\sum \]-rdical of R is the intersection of all basic ideals of R.
Theorem 4. Any \[\sum \]-semisimple ring is isomorphic to a subdirect sum of basic rings.
Theorem 5. Let R be an associative ring. Suppose that the set \[\sum \] includes only one element R, then the \[\sum \]-radieal of R, the \[\sum \]-semisimfple and the basic rings become the
Jacobson radical, the Jacobson semisimple and the primitive rings respectively.
Definition 6. An element \[m \in \mathfrak{M}\] is called strictly cyclic if \[m \in mR\]. \[\mathfrak{M}\] is called special if there exists a subset M of \[\mathfrak{M}\] such that every element \[m \in M\] is strictly cyclic
and 0:\[\mathfrak{M} = \mathop \cap \limits_{m \in M} 0:m\]
Definition 7. A module \[\mathfrak{M}\] is called a special dense module if and only if (i)\[\mathfrak{M}\] is
special, (ii) \[\mathfrak{M}\] is a F-space as stated in [1] ,(\[\mathfrak{M}\]) suppose that\[{u_{{i_1}}},{u_{{i_2}}},...,{u_{{i_n}}}\] be arbitrary
finite F-independent elements and \[{u_{{i_1}}}r \ne 0,{u_{{i_j}}} = 0,j \ne 1\] for an element \[r \in R\], then there exists an element \[t \in R\] such that .\[{u_{{i_1}}}tR = \mathfrak{M},{u_{{i_j}}} = 0,j \ne 1\].
Let S be the set of all free elements of \[\mathfrak{M}\] as stated in [1]. It is clear that S is a
strictly cyclic set and \[\mathfrak{M}\] is a special module.
Now put I to be the class of all speciall dense modules with M = S, Denote \[{\Lambda _s} = \{ {\mathcal{M}_m}\} \] where =\[{\mathcal{M}_m} = 0:m,m \in S\], and \[\sum = \{ \mathcal{M}|\mathcal{M} \in {\Lambda _s},s \subset \mathfrak{M} \in I\} \]; \[{\hat \sum }\] as stated before. Then we can show that \[{J^*} = \mathop \cap \limits_{\mathcal{M} \in \sum } \mathcal{M} = \mathop \cap \limits_{\hat \mathcal{M} \in \hat \sum } \hat \mathcal{M}\] is a \[\sum \] -radical and \[{J^*} \subset J\], where J is Jacobson radical.
Definition 8. The above stated \[\sum \]-radical \[{J^*}\] will be called the quasi Jacobson radical.
A ring R is Called quasi Jacobson semisimple ring if and only if the quasi Jacobson
radical \[{J^*}\] = 0.
Theorem 6. Let R be a quasi Jacobson semisimple ring, then R is isomorphic to
a subdirect sum of quasi primitive rings. 相似文献
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研究了一个产生于非线性几何光学中的非严格双曲守恒律系统.该系统具有强非线性流函数项,且狄拉克激波可能同时出现在解的两个状态变量中.通过未知函数的一个变换,该系统的非线性流函数项得到弱化,从而其黎曼问题被完全解决. 相似文献
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This paper deals with optimizing the cost of set up, transportation and inventory of a multi-stage production system in presence of bottleneck. The considered optimization model is a mixed integer nonlinear program. We propose two methods based on DC (Difference of Convex) programming and DCA (DC Algorithm)—an innovative approach in nonconvex programming framework. The mixed integer nonlinear problem is first reformulated as a DC program and then DCA is developed to solve the resulting problem. In order to globally solve the problem, we combine DCA with a Branch and Bound algorithm (BB-DCA). A convex minorant of the objective function is introduced. DCA is used to compute upper bounds while lower bounds are calculated from a convex relaxation problem. The numerical results compared with those of COUENNE (http://www.coin-or.org/download/binary/Couenne/), a solver for mixed integer nonconvex programming, show the rapidity and the ?-globality of DCA in almost cases, as well as the efficiency of the combined DCA-Branch and Bound algorithm. We also propose a simple heuristic algorithm which is proved by experimental results to be better than an existing heuristic in the literature for this problem. 相似文献