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31.
W D Tiner 《International Journal of Project Management》1985,3(1):13-18
In order to control a project, construction management requires project information. This is obtained through accounting, estimating, cost management and scheduling functions which produce project reports. These reports are best obtained by subdividing the project into small parts. The ways in which each of these functions subdivides a project in order to produce its reports is discussed, together with a means of interrelating this information with a technique known as the work breakdown structure. 相似文献
32.
V. G. Khoruzhaya K. E. Kornienko P. S. Martsenyuk T. Ya. Velikanova 《Powder Metallurgy and Metal Ceramics》2006,45(5-6):251-258
Methods of differential thermal analysis, x-ray diffraction, microstructural analysis and electron probe microanalysis are
used to study alloys of the Al-Rh system over the whole concentration range. It is established that the phase of equiatomic
composition AlRh melts congruently at 2060°C and it has an extended range of homogeneity (45.1–54.2 at.% Rh). The solubility
of aluminum in rhodium reaches 9 at.%, decreasing to 6 at.% at 850°C. Coordinates are determined for the eutectic point l
⇆ AlRh + 〈Rh〉 as 70 at.% Rh and 1715°C. The existence of intermediate phases, their crystal structure, and also the method
of forming phases in the field of composition rich in aluminum given in publications are confirmed.
__________
Translated from Poroshkovaya Metallurgiya, Nos. 5–6(449), pp. 48–56, May–June, 2006. 相似文献
33.
Wei Hui 《Frontiers of Computer Science in China》2007,1(3):361-372
Almost all applications of Artificial Neural Networks (ANNs) depend mainly on their memory ability. The characteristics of
typical ANN models are fixed connections, with evolved weights, globalized representations, and globalized optimizations,
all based on a mathematical approach. This makes those models to be deficient in robustness, efficiency of learning, capacity,
anti-jamming between training sets, and correlativity of samples, etc. In this paper, we attempt to address these problems
by adopting the characteristics of biological neurons in morphology and signal processing. A hierarchical neural network was
designed and realized to implement structure learning and representations based on connected structures. The basic characteristics
of this model are localized and random connections, field limitations of neuron fan-in and fan-out, dynamic behavior of neurons,
and samples represented through different sub-circuits of neurons specialized into different response patterns. At the end
of this paper, some important aspects of error correction, capacity, learning efficiency, and soundness of structural representation
are analyzed theoretically. This paper has demonstrated the feasibility and advantages of structure learning and representation.
This model can serve as a fundamental element of cognitive systems such as perception and associative memory. 相似文献
34.
A compact dipole antenna for the terrestrial digital multimedia broadcasting (TDMB) application is presented. The length of the antenna is about 0.06λ at the TDMB resonance frequency of 190 MHz. Miniaturization of the antenna is achieved by using meander structures and lumped elements. The proposed antenna has two resonance frequencies and covers the TDMB band from 174 MHz to 216 MHz in Korea. The antenna has good impedance bandwidth and radiation characteristics for the TDMB. The experimental results of the designed dipole antenna are presented and analyzed. 相似文献
35.
An optimal control problem with nonsmooth performance criterion described by a system of ordinary differential equations is considered. Necessary first-order optimality conditions are obtained. 相似文献
36.
37.
城市化进程中的小城镇交通初探 总被引:4,自引:0,他引:4
通过对小城镇城市结构、路网结构、交通结构和交通管理特征进行详细分析,得出小城镇交通问题症结所在,并初步提出小城镇交通规划和交通治理的对策。 相似文献
38.
39.
This study examined the role of marital conflict structure--who desires and requests change versus who responds to the change request--in spouses' cardiovascular responses to marital interactions. Forty-one couples discussed 2 marital topics: one in which the wife desired change in the husband, and one in which the husband desired change in the wife. Cardiovascular responses were assessed at 2-min intervals. Results indicated that marital conflict structure moderates cardiovascular reactivity during negative marital interactions: Husbands and wives whose interactions were characterized by high levels of negative behavior showed the most pronounced diastolic blood pressure reactivity, but only when they were in the role of desiring change in their spouses. Implications for gender differences in marital conflict physiology are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.