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301.
论述了石油工业企业在社会主义市场经济体制下切实加强和重视企业生产经营活动经济效益分析工作的重要性,提出了油气田生产经营活动经济效益分析的基本思路和方法,通过对相应的油气田生产成本、产量的计算分析,给出了降低油气田生产成本的对策;确定了油气田效益产量和无效益产量的方法,讨论了经济效益分析工作中应当注意的几个问题。 相似文献
302.
Jia-Sheng heh 《Mathematical and Computer Modelling》1999,30(11-12)
Problem solving is a style of thinking, which transforms a given problem to the goal state through a so-called PS (problem solving) path. Different from the traditional GPS (General Problem Solver) approach, the focus in this paper is placed on how to judge the performance of PS paths, that is, the evaluation problem of problem solving.A series of PS paths point from the given source problem to the destination goal, then form a PSN (PS Network). This paper proposes an elaborated CPSN (Coordinate Problem Solving Network) as the evaluation model of problem solving. In CPSN, each problem is assigned a unique coordinate and then each PS path can have an evaluation vector. Several examples show such arrangement can give more insight to PS paths.Furthermore, an incremental learning algorithm is developed for the update of CPSN. When a new PS path is obtained, it is not necessary to recalculate the whole CPSN. Examples show such algorithm provides a more efficient way in finding new PS paths. 相似文献
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305.
Alenia SIR-M单脉冲二次雷达是中国民航早期引进的监视系统,随着运行时间的增长,由于设备老化所引起的各种故障告警日渐增多,而其中又以雷达发射功率低等问题较为常见。本文根据此设备的发射信号流程,对有可能造成低功率告警的环节和原因进行了总结,并结合具体的案例,介绍了Alenia SIR-M设备低功率告警的分析和处理方法。 相似文献
306.
In the study, we propose a concept of incremental fuzzy models in which fuzzy rules are aimed at compensating discrepancies resulting because of the use of a certain global yet simple model of general nature (such as e.g., a constant or linear regression). The structure of input data and error discovered through fuzzy clustering is captured in the form of a collection of fuzzy clusters, which helps eliminate (compensate) error produced by the global model. We discuss a detailed architecture of the proposed rule-based model and present its design based on an augmented version of Fuzzy C-Means (FCM). An extended suite of experimental studies offering some comparative analysis is covered as well. 相似文献
307.
吴凤竹 《武汉科技学院学报》2011,(5)
以武汉纺织大学为例,在问卷调查的基础上,介绍并分析非英语专业大学生的文学素养情况。调查结果显示:大部分学生比较喜欢文学,也很期待在老师的帮助下培养和提高自己的文学素养,但由于语言能力和平时积累的有限,他们普遍比较欠缺真实的文学素养,从而影响了语言理解和输出的质量。 相似文献
308.
A two-level atom is put into a cavity comprising a transparent dielectric with one-side output coupling. An analytical expression of the time-dependence Casimir–Polder force in such a system is obtained. Our results show that the force finally tends to a steady negative value after a short-time damped oscillation. The effects on the force of the relative dielectric constant and the cavity size are also discussed in detail, respectively. 相似文献
309.
The most important function of a network is for transporting traffic. Due to the low traffic capacity of network systems under the global shortest path routing, plenty of heuristic routing strategies are emerging. In this paper, we propose a heuristic routing strategy called the incremental routing algorithm to improve the traffic capacity of complex networks. We divide the routing process into N(the network size) steps and, at each step, we heuristically calculate all the routes for one source node considering both the dynamic efficient betweenness centrality and node degree information. We do extensive simulations on scale-free networks to confirm the effectiveness of the proposed incremental routing strategy. The simulation results show that the traffic capacity has been enhanced by a substantial factor at the expense of a slight lengthening in the average path. 相似文献
310.
本文针对太阳能光伏发电系统的功率输出非线性特点,提出一种结合数据库,利用电导增量实现最大功率跟踪的系统。论文根据光伏阵列的特性,建立光伏系统数学模型,采用电导增量法建立历史和实时数据库,通过数据库查询尽快跟踪功率变化,调整占空比,达到实时最大功率跟踪。系统采用MSP430作为控制器,定时方式产生PWM控制变换器开关。研究结果表明,系统可以快速跟踪最大功率变化,提高跟踪精度和输出功率,相对传统电导增量法本文方法跟踪速度提高5%-20%。 相似文献