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991.
以铁的γ射线散射谱为例说明康普顿轮廓数据处理的全过程。主要包括:减本底、退卷积、标度变换、吸收修正、截面修正、多次散射修正等。  相似文献   
992.
We extend the classical newsvendor problem by introducing a downside risk constraint from the perspective of inventory control. At the beginning of a replenishment period the newsvendor will place an order, then he will review the inventory level at the end of the period. If the inventory level is positive then he will bear the holding cost and if the inventory level is negative then he will bear the backorder cost. The optimal order quantity has a simple form. We analyze the form of the optimal order quan-tity when we restrict that the probability that the cost level is larger than or equal to a fixed cost constant is less than a fixed value of probability. At last, we analyze the case that the fixed cost constant is equal to the expected cost.  相似文献   
993.
A wide range of literature concerning classical asymptotic properties for linear models with adaptive control is available, such as strong laws of large numbers or central limit theorems. Unfortunately, in contrast with the situation without control, it appears to be impossible to find sharp asymptotic or nonasymptotic properties such as large deviation principles or exponential inequalities. Our purpose is to provide a first step towards that direction by proving a very simple exponential inequality for the standard least squares estimator of the unknown parameter of Gaussian autoregressive process in adaptive tracking.  相似文献   
994.
995.
This paper introduces agent-based methodology to build a distributed autonomic storage system infrastructure, and an effectively negotiation mechanism based on agent is applied for data location. We present Availability-based Data Allocation (ADA) algorithm as a data placement strategy to achieve high efficient utilization of storage resources by employing multiple distributed storage resources. We use Bloom filter in each storage device to track the location of data. We present the data lookup strategy that small size of read request is handled directly, and large size of read request is handled by cooperation with storage devices.The performance evaluation shows that the data location mechanism is high available and can work well for heterogeneous autonomic storage systems.  相似文献   
996.
PLC控制已成为自动化控制的主流,PLC系统设计技能培养刻不容缓。本文从教学角度重点探讨了掌握共性灵活运用PLC的能力培养、充分利用网络资源以及PLC实践学习法三个问题,并就相应的策略予以了分析。  相似文献   
997.
This paper further investigates cluster synchronization in a complex dynamical network with two-cluster. Each cluster contains a number of identical dynamical systems, however, the subsystems composing the two clusters can be different, i.e., the individual dynamical system in one cluster can differ from that in the other cluster. Complete synchronization within each cluster is possible only if each node from one cluster receives the same input from nodes in other cluster. In this case, the stability condition of one-cluster synchronization is known to contain two terms: the first accounts for the contribution of the inner-cluster coupling structure while the second is simply an extra linear term, which can be deduced by the "same-input" condition. Applying the connection graph stability method, the authors obtain an upper bound of input strength for one cluster if the first account is known, by which the synchronizability of cluster can be scaled. For different clusters, there are different upper bound of input strength by virtue of different dynamics and the corresponding cluster structure. Moreover, two illustrative examples are presented and the numerical simulations coincide with the theoretical analysis.  相似文献   
998.
We discuss the linear conjugate boundary value problems on the unit circle and the real axis. We obtain some Fredholm integral equations. Using thess equations we discuss the solvable conditions on these problems and we also give a direct method for the extension problems on the real axis.  相似文献   
999.
Public discourse in Western democracies, particularly in the United States, is far from the Habermasian ideal of citizens engaging in a rational discussion of public affairs. Rather than providing an arena for informed deliberation, the growing expertise of the media, lobbyists, and politicians has sub-optimized the current system of discourse to focus on emotional manipulation and the creation of polarized interests, each competing with each other for dominance. Avoiding a potentially disastrous outcome from this unbalancing of public discourse requires a revitalization of the public sphere and a return of the citizen voice in public decision making. To that end, systems thinkers have a tremendous opportunity and can play an important role. This article will explore the current challenges facing public discourse and outline that potential role.  相似文献   
1000.
This paper presents a method to analyze and calculate the angular glint of targets. By parting the target to very small size cells, using high-frequency approximation, the near-field radar cross section (RCS) is calculated based on the scattering from complex targets and environments (SCTE) system, and the angular glint is calculated by the phase grads. The results show that the angular glint can be calculated exactly in the SCTE system, and this method is correct and efficient. In the near-zone, the far-field theory is not applicable and the angular glint should be calculated by the near-field theory.  相似文献   
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