Time constraints set by prime contractors for their sub-contractors

The concept of pacing is described in an articulate manner which will enable readers to discuss the views put forwards. The nine major activities are divided into two types and are discussed in detail together with the methods used by the prime contractors to allocate time windows and the underlying logic employed.     

Conditions of formation and magnetic properties of tetragonal Fe14La2B

Tetragonal Fe₁₄La₂B (a = 0.883 nm, c = 1.236 nm)is stable below 860°C. At 25°C it has a magnetization approaching 1.1 T in a field of 2000 kA/m. Its anisotropy field is considerably lower than that of related Fe₁₄Nd₂B or Fe₁₄Pr₂B.     

The solubility of ethane in triethylene glycol monomethyl ether

The solubility of ethane in triethylene glycol monomethyl ether (TEGMME) has been measured at 40, 70 and 100°C at pressures up to 9.2 MPa. The solubility data obtained are compared with those of ethane in other physical solvents. The results were correlated with the Peng-Robinson (1976) equation of state and the interaction parameters were obtained. Henry's constants were also determined.     

Analysis and optimization of series-gated CML and ECL high-speedbipolar circuits

An analytical model for calculating the propagation delay time of two-level series-gated current mode logic (CML) and emitter-coupled logic (ECL) high-speed bipolar circuits is presented. The analytical delay model accounts for all the device parasitics and the device sizes of the two levels. Moreover, high-current effects are also considered in the developed model. Exploiting these two features, the model has been successfully applied in optimizing the design of a variety of two-level series-gated CML and ECL circuits for maximum speed (minimum delay). A comparison with the results obtained by SPICE is presented to verify the applicability of the proposed model     

Load-line analysis of i.i.l.

A d.c. load-line analysis of i.i.l. structures is performed. Calculations are made of logic levels, noise margins and effective circuit parameters. Although the analysis is simple, it enhances the understanding of the circuit operation, and its predictions are in agreement with experiment and with more complicated analyses.     

Nonsaturated integrated injection logic

Conventional integrated-injection-logic structures suffer from strong saturation of the n?p?n transistors. This increases the storage time, and hence puts a limitation on the propagation delay of the structures. A current-control technique is given to reduce this effect without changing the basic i.i.l. structure.     

Base component of gain and delay time in base-implanted bipolar transistors

This paper uses a numerical analysis, backed by analytic solutions for some cases, to study the dependence of the base component of current gain and delay time in base implanted bipolar transistors on the base impurity porfile. Results are presented in normalised form to facilitate their use in predicting device performance during the processing-device design stage.     

An Indexing Method for Answering Queries on Moving Objects

We consider the problem of indexing a set of objects moving in d-dimensional spaces along linear trajectories. A simple external-memory indexing scheme is proposed to efficiently answer general range queries. The following are examples of the queries that can be answered by the proposed method: report all moving objects that will (i) pass between two given points within a specified time interval; (ii) become within a given distance from some or all of a given set of other moving objects. Our scheme is based on mapping the objects to a dual space, where queries about moving objects are transformed into polyhedral queries concerning their speeds and initial locations. We then present a simple method for answering such polyhedral queries, based on partitioning the space into disjoint regions and using a B+-tree to index the points in each region. By appropriately selecting the boundaries of each region, we guarantee an average search time that matches a known lower bound for the problem. Specifically, for a fixed d, if the coordinates of a given set of N points are statistically independent, the proposed technique answers polyhedral queries, on the average, in O((N/B)^1−1/d⋅(log _B N)^1/d+K/B) I/O's using O(N/B) space, where B is the block size, and K is the number of reported points. Our approach is novel in that, while it provides a theoretical upper bound on the average query time, it avoids the use of complicated data structures, making it an effective candidate for practical applications. The proposed index is also dynamic in the sense that it allows object insertion and deletion in an amortized update cost of log _B(N) I/O's. Experimental results are presented to show the superiority of the proposed index over other methods based on R-trees. recommend Ahmed Elmagarmid     

Scaling merged single-device-well MOSFETs for very large scale integration

Single-Device-Well (SDW) MOSFETs are high density MOSFET structures based on merging two MOSFET devices; a surface channel device and a buried channel device sharing the same device well and the same gate. SDWs offer a potential device area saving of 50%. The merits of the merged SDW MOSFETs are further enhanced in a scaled down MOSFET VLSI technology. This is the subject of this paper.     

组合锥形液体贮罐的简化设计方法

组合圆锥-圆柱形壳形式的钢贮罐是一种常见的用于储存液体的压力罐。大部分此类压力罐的破坏都由于钢壳的失稳而引起。引起这些破坏的主要原因是没有适当的设计方法来对这类结构进行设计。在本次研究中,提出了简化的设计方法,以保证静水加载的组合钢罐在发生屈曲时的安全。应用非线性有限元模型进行数值模拟,对大变形和几何缺陷对钢罐稳定性的破坏作用进行分析。采用有限元计算结果与非线性回归分析建立函数,将壳的总应力与膜应力关联起来。采用算例说明了所提议设计方法的应用。