运用模糊数学原理估算水利水电工程的成本

为了适应水利水电工程成本快速估价的需要,提出了一种建立在模糊数学基本原理基础上的估价模型,克服了工程量清单计价方法计算繁琐的缺点。通过实例说明了该方法的科学性、合理性及实用性。     

An Interval Fuzzy Multiobjective Watershed Management Model for the Lake Qionghai Watershed, China

Integrated watershed management is required to ensure the reasonable use of resources and reconcile interactions among natural and human systems. In the present study, an interval fuzzy multiobjective programming (IFMOP) method was used to solve an integrated watershed management problem. Based on system analysis, an IFMOP model suitable for a lake watershed system {IFMOPLWS} was developed and applied to the Lake Qionghai watershed in China. Scenario analysis and an interactive approach were used in the solution process. In this manner, various system components were incorporated into one framework for holistic consideration and optimization. Integrality and uncertainty, as well as the multiobjective and dynamic characteristics of the watershed system, were well addressed. Using two scenarios, two planning schemes were generated. Agriculture, tourism, macroeconomics, cropland use, water supply, forest coverage, soil erosion, and water pollution were fully interpreted and compared to identify a preferable planning alternative for local agencies. This study showed that the IFMOPLWS is a powerful tool for integrated watershed management planning and can provide a solid base for sustainable watershed management.     

脆断事故的原因分析和预防措施

分析高强度材料和大型工程结构元件发生低应力脆性断裂的原因及条件，指出传统强度设计理论的局限性，从设计和工艺上提出防止发生低应力脆断事故的具体措施，给使用高强度材料和设计大型工程结构元件时提供参考。     

Preparation of Ultra—fine Aluminum Nitride in Thermal Plasma

Ultra-fine aluminum nitride has been synthesized by the evaporation of aluminum powder at atmospheric-pressure nitrogen plasma in a hot-wall reactor.The average size of aluminum nitride particle is 0.11μm measured by scanning electric mirror(SEM),and the purity is at least over90% evaluated by X-Ray diffraction(XRD).The conversion of Al powder to aluminum nitride is strongly depended on the injection of NH3.Typical experimental parameters such as the feed rate of raw material,the flow rate of ammonia and the position of injecting aluminum powder into the reactor are given.     

诚信对兖矿资本运营的影响

1 诚信对兖矿资本运营的贡献1.1 在兖矿股票发行方面 1988年4月兖矿煤业在纽约、香港打响了上市的第一炮,这次兖州煤业全球发行8.2亿股,发行总收入折合人民币2.58亿元。可是当时的背景是亚洲金融危机爆发所带来的负面影响尚未完全消除,世界各地失信现象屡屡发生。活力28集团股份有限公司股票上市申报时虚增利润1667.7万元,上市后三年虚增利润21124.3万元,1998年公司在配股时公开披露国家股股东荆州市国资局以现金2320万元认购     

^17O系统的R矩阵分析

采用多道多能级R矩阵理论,全面系统地分析~(17)O系统中10.5 MeV激发能以下有关~(16)O(n,n)~(16)O·~(16)O(n,a)~(13)C和~(13)C(a,a)~(13)C的全部实验数据。有关~(16)O的中子反应截面计算值被收入中国评价数据库CENDL-2和美国的评价数据库ENDF/B-6。对在R矩阵分析中如何确定本底、道半径和边界条件等问题予以讨论。     

弹药内弹道性能检验新方法数学模型的建立

本文对弹药内弹道性能检验的传统方法存在的问题进行了分析,提出了一种新的检验方法,重点对新的检验方法的数学模型的建立过程进行了论述。并对数学模型的精度进行了分析、检验和验证。     

Ni对球墨铸铁热处理的影响

采用电子探针，图象分析仪、差质变分析仪和Ｘ射线衍仪定量研究了Ｎｉ在球铁中的分布和Ｎｉ铸态球铁组成相比例奥氏体中含碳量以及贝氏体转变ＴＴＴ曲线线的影响，结果表明，Ｎｉ在球铁中呈连续负偏析，其加入可以影响球铁组成上比例，并使粤氏体中含碳量和贝氏体转变孕育期期增加。     

铝锂合金力学性能的各向异性

针对当前困扰铝锂合金实际应用的各向异性问题，概述关于铝锂合金中各向异性的表现规律，产生机理及对于降低各向异性所采用的方法等方面的研究现状和进展，对铝锂合金各向异性表现与微观组织结构的关系以及目前克服各向异性所采用方法的局限性进行分析。就此提出，若彻底解决这一问题则必须采用更先进的合金化方法及热加工工艺，研制新一代铝锂合金的观点和研究方向。