基于ISM与M-F模型的公务员工资普调频率研究

以普调频率为核心的工资增长机制,是我国公务员工资制度改革悬而未决的难点问题,其关键在于分析影响因素并确定普调周期。文章采用ISM、M-F等方法,对我国公务员工资普调频率影响因素进行量化分析,旨在通过研究各因素影响时效的衍变规律,寻求长期稳态下最适宜的普调周期。研究发现,基于时效周期的工资普调影响指标体系包含24项因素,其中CPI等8项流量因素构成短期时效层,自身变化及影响时效短,易波动,综合影响期为1.55年;平均任职时间等13项存量因素构成中期时效层,指标变动具有长期累积性,综合影响期为3.11年;工资差异结构等3项支配因素构成长期时效层,反映工资供求矛盾状态,综合影响期为4.53年;在24项因素综合作用下,系统于2.34年达到了长期稳态水平,各项影响因素实现了最佳平衡,可近似将2.50年设计为普调周期。     

微乳液-水热结合法制备光色可调的α-NaYF4:Yb,Er,Tm纳米材料

采用微乳液-水热结合法制备了NaYF4:Yb3+,Er3+,Tm3+纳米粒子,利用X射线衍射(XRD)、扫描电镜(SEM)等手段对样品的物相、结构和形貌进行了分析与表征。产物的X射线衍射峰与标准卡片PDF#77-2042完全一致,属于立方相NaYF4;SEM图片显示所制备的纳米粒子形貌和粒径都比较均一,为120nm左右的棉花状小球,由纳米微粒聚集而成;在980nm光的激发下,纳米粒子能够同时发出蓝光(438和486nm)、绿光(523和539nm)和红光(650nm);通过调节Tm3+:Er3+的比例(0,0.5,0.8,1,2,3,5,7),由色度坐标图(CIE)可以看出当Tm3+和Er3+的比例从0增加到2时,样品的整体发光光色是向绿光方向移动;当Tm3+和Er3+的比例为1:1时,得到伪白光;Tm3+和Er3+的比例从2到7时,样品整体的发光向红光方向移动。     

Dual channel detection–diode array and mass spectroscopy (El or Cl)–in HPLC

Simultaneous recording of UV and mass spectra (electron impact or chemical Ionization) in conventional HPLC is described. The LC eluent is divided into two parts; one is directed into a diode array detector and the other is introduced into the mass spectrometer via a particle beam interface. The analysis of the steroid esters of a pharmaceutical formulation illustrates the possibilities of dual channel (DAD-MS) HPLC detection.     

Ce-MCM-48介孔分子筛的合成、表征和催化性能

尝试以混合模板剂pH调节水热合成掺入铈的介孔分子筛CeMCM48,并采用X射线衍射、高分辨透射电镜、紫外可见漫反射、X射线荧光光谱、氮气吸附脱附测试手段对样品进行表征.结果表明,新合成的掺铈介孔材料仍保持立方介孔的有序结构,有序性及吸附性能得到改善.所合成的掺铈的立方介孔分子筛对环己烷的液相氧化反应的催化活性和选择性较高.CeMCM48催化环己烷氧化反应的转化率较MCM48催化的转化率提高了8.3%～14.2%,对主要产物的选择性提高了63.4%～68.8%.     

A unified theory for coherent systems in reliability II. A unified viewpoint on multinary coherent systems through monotone coherence and relevance

Binary coherent system theory has played an important part in reliability. Its extension to (‘degradable’ or ‘multistate’ or) multinary systems has recently been considered in various papers, through various definitions. This paper studies the most general model for multinary systems, proposes a unified viewpoint on multinary coherent systems and gives unified arguments to apply and to investigate further the binary and multinary cases. In a more detailed way, the ‘helpful bridge’ lately proposed by Block and Savits¹ between the binary and multinary cases is completed and multinary systems then can be studied in terms of monotone binary coherent systems, introduced in a companion paper.² Through various results, multinary systems are examined in terms of structure functions and of life functions; fundamental relations for their analysis are obtained with their set characterizations; the main axis that can be retained among the numerous types of coherence is emphasized, in a unified way, through relevance; reliability models are examined through performance processes, life lengths and performance functions; and Birnbaum's factors of importance are thoroughly extended to the multinary case. Fundamental results proposed in previous studies are thus completed with a shorter unified approach.     

Performance analysis of single stage kanban controlled production systems using parametric decomposition

We present a new approach that permits efficient performance analysis of kanban systems with general demand processes, material arrival processes, and service times. The approach is based on parametric characterization of the traffic processes (arrival and departure) in the network and uses two-moment approximations to estimate performance measures at individual stations. We derive traffic flow constraints that are particular to closed queuing networks with synchronization stations and use these to establish relationships between the parameters characterizing arrival and departure processes at the stations in the network. The resultant set of non-linear equations is solved to estimate network performance measures. Numerical studies show that the approach is not only fast but also reasonably accurate when compared to simulation. These studies also provide insights with respect to the impact of different types of variability on the performance of a kanban system. This work also provides a fundamental building block that can be used in the analysis of multi-stage kanban systems. AMS Subject Classifications 68M20, 60K20, 90B05, 90B30     

Approximation of the steepest descent direction for the O-D matrix adjustment problem

In this paper, a method to approximate the directions of Clarke's generalized gradient of the upper level function for the demand adjustment problem on traffic networks is presented. Its consistency is analyzed in detail. The theoretical background on which this method relies is the known property of proximal subgradients of approximating subgradients of proximal bounded and lower semicountinuous functions using the Moreau envelopes. A double penalty approach is employed to approximate the proximal subgradients provided by these envelopes. An algorithm based on partial linearization is used to solve the resulting nonconvex problem that approximates the Moreau envelopes, and a method to verify the accuracy of the approximation to the steepest descent direction at points of differentiability is developed, so it may be used as a suitable stopping criterion. Finally, a set of experiments with test problems are presented, illustrating the approximation of the solutions to a steepest descent direction evaluated numerically. Research supported under Spanish CICYT project TRA99-1156-C02-02.     

Combinatorial approximation algorithms: a comparative review

This paper is a comparative review of three related books:Giorgio Ausiello, Pierluigi Crescenzi, Giorgio Gambosi, Viggo Kann, Alberto Marchetti-Spaccamela, Marco Protasi, Complexity and Approximation (Combinatorial Optimization Problems and Their Approximability Properties), second printing, Springer, Berlin, 2003, ISBN 3-540-65431-3, 524 pp., €53.45 (first printing 1999).Juraj Hromkovi?, Algorithmics for Hard Problems (Introduction to Combinatorial Optimization, Randomization, Approximation, and Heuristics), second edition, Springer, Berlin, 2003, ISBN 3-540-44134-4, 544 pp., €53.45 (first printing 2001).Vijay Vazirani, Approximation Algorithms, second printing, Springer, Berlin, 2002, ISBN 3-540-65367-8, 380 pp., €37.40 (first printing 2001).     

具有独立子块的大系统目标规划问题的解法

分解之后如何进行协调解决大系统规划问题的关键．本文通过利用子系统目标值所提供的信息进行大系统分解之后的协调，并提出了求解具有独立子块的大系统规划问题的串式调优法，同时研究了有关原问题和各子问题最优解的性质．     

浅谈"平分"方法在物理实验中的应用

介绍了“平分”方法的数学原理,结合典型的物理实验,针对具体的实验过程,给出了该方法的一些应用实例,并讨论了在实验中应用该方法的重要性.