A new method to estimate DOA in CDMA system in multi-path environment

An algorithm for direction angle of arrival（DOA） estimation and array calibration of signals from multiple mobile users in the CDMA systems and multi-path environment was presented . The main idea is that the algorithm employs code-matched filter and model of the inter-symbol interference and multiple-access interference exactly. The correlation matrices of the received signals before and after code-matched filtering were employed to eliminate the effect of the additive white Gaussian noise, and a new mathematical problem was created, a new maximum likelihood method based on the strong law of large number was derived for DOA estimation and array calibration. Computer simulation results prove that the algorithm is effective.     

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

1IntroductionAlthoughwaterresourcesarerenewable,theirutilizationissubjecttoheavypres-surepresently.Thestudyonwaterresourcesrenewabilitywillprovideatheoreticalbasisanddecision-makingreferenceforthesustainableutilizationofwaterresources[1,2].Wa-terresourcesrenewability[3]isacomprehensiveconcept;itreferstotheabilityofwaterresourcestobeutilizedrepetitivelybyhumansthroughnaturalactionorartificialman-agement.Affectedbybothnaturalandsocialfactors,thecomprehensiveassessmentonwaterresourcesrenewability…     

A new hybrid method——combined heat flux method with Monte-Carlo method to analyze thermal radiation

A new hybrid method, Monte-Carlo-Heat-Flux （MCHF） method, was presented to analyze the radiative heat transfer of participating medium in a three-dimensional rectangular enclosure using combined the Monte-Carlo method with the heat flux method. Its accuracy and reliability was proved by comparing the computational results with exact results from classical ＂Zone Method＂.     

A fast method to prepare water samples for ~(15)N analysis

Automatic element analyser is often used to prepare organic matters tor 15N analysis. It is seldom used to prepare water samples. Water samples are conventionally dealt with by Kjeldahl-Rittenberg technique. But it requires tedious and labor-intensive sample preparation. A fast and reliable method is proposed in this paper to prepare water samples for 15N analysis.     

A new approach to predicting mining induced surface subsidence

1 INTRODUCTIONMining induced surface subsidence often re-sults in various kinds of damages to the structuresandinfrastructures in the subsidence area[1 4]. Thepipes will be broken and fractured,the buildingswill be caused to tilt or collapse and the roadfoun-dation and acequia will be damaged because of thesubsidence . Especially in the case of open stopemining under hard rock formation,this subsidencewill suddenly occurr . For example , at about 11p.m.on December 27 ,1999 ,large scale of…     

Study on the holistic model for water resources system

1ForewordFortheinherentcomplexityofwaterresourcessystem,efficientanalysistoolsarenecessaryfortherationalallocationofwaterresourcesanddecision-makingconcerningsustainabledevelopmentinariverbasin.Recently,studiesonthecompetitionofwateruseamongdifferentsectorsanditsmacrodecision-makingareverymuchemphasizedinthefieldofhydrology.Thesestudiesareoftencarriedoutbyusingaholisticmodelin-cludinghydrologiccomponents,agriculturalandindustrialproduction,humanliving,ecosystemandenvironment.Uptonowtherearetwo…     

A new production method of ammonium metatungstate—Donnan dialysis method

A new method for production of ammonium metatungstate (AMT) directly from ammonium tungstate solution—Donnan dialysis method is advanced. Laboratory experiments are conducted by a Donnan dialysis cell with the membrane area of 140 mm ×200 mm. The result shows that the transformation rate of AMT reaches 370 g-WO₃/(m²·h), the recovery ratio of AMT by the Donnan dialysis method is nearly 100%, and the loss of tungsten is less than 0.2%. It has been proved that the Donnan dialysis method is effective for production of AMT. Synopsis of the first author Zhou Kanggen, professor, born in March 1963, majoring in extraction matallurgy of rare metals, application of membrane technology in metallurgical process.     

A new method of constructing measure

By using a well known result in combinatorics, named Knig Lemma, this paper generalized the method of constructing measure by repeated subdivision, which was a basic tool for fractal geometry. A more general method was presented to construct measure, which was an essential improvement to the existing result. The proof employed a skill similar to that for Knig Lemma, which helped to avoid using the compactness in Euclidean space. Two conditions of the existing method were found not necessary.     

A new method for simulating human emotions

How to make machines express emotions would be instrumental in establishing a completely new paradigm for man machine interaction. A new method for simulating and assessing artificial psychology has been developed for the research of the emotion robot. The human psychology activity is regarded as a Markov process. An emotion space and psychology model is constructed based on Markov process. The conception of emotion entropy is presented to assess the artificial emotion complexity. The simulating results play up to human psychology activity. This model can also be applied to consumer-friendly human-computer interfaces, and interactive video etc.     

A new monitoring method of cable tension of cable-stayed bridge—fiber Bragg grating method

1INTRODUCTION Thestayed cablesofcable stayedbridgesare mainload bearingcomponents.Cabletensionis oneofthemostimportantcriterionforjudgingwhetheracable stayedbridgeisinorder[1].So,if thecabletensionofcable stayedbridgecanbemo nitoredon line,thepracticalsit…     

基于集对分析的双向综合教学评价模型应用

教学质量的评价应着眼于教师和学生之间进行双向综合评价。建立综合教与学两方面影响因素的指标体系是教学质量评价的前提和基础。运用基于集对分析（SPA）的同异反教学评价模型,结合层次分析法确定指标权重,并对评价所得联系度的不确定性展开分析,从而对教学评价系统信息的确定性和不确定性进行研究,使评价结果更加客观、可信。     

基于集对分析的自然灾害风险度综合评价研究

自然灾害风险度综合评价是一种影响因素较多的、复杂的系统工程.基于集对原理提出了自然灾害风险度评价新方法--集对分析法(SPAM).SPAM考虑标准分类的模糊性,避免直接确定联系度中差异度(分量)系数.SPAM概念清晰,结构简单,计算简洁,评价结果可信.以全国各省自然灾害资料为例,探讨集对分析法在自然灾害风险度评价中的应用,研究表明,SPAM是可行而有效的.     

水资源承载力的集对势-偏联系数评价模型

水资源承载力评价是区域水资源系统可持续发展战略的重要组成部分,然而现行评价方法大多依赖于静态数据构建研究对象与等级标准之间的关联函数,而对信息的动态性考虑不足。针对这个问题,利用集对分析态势评价法和偏联系数方法探索不同等级之间的动态平衡机制,构建了一种融合信息演化的水资源承载力评价模型。首先,参照相关研究成果,获取水资源承载力评价指标体系及等级标准,计算各研究对象的三元评价联系数;其次,针对传统集对势与评价等级值不能在数值上对应的不足,研究提出了集对势特征值的概念,对系统所处的态势及等级进行统一量化表征;然后,分析三元联系数中相邻联系分量之间的演化规律,基于一阶偏联系数方法,利用各分量与相邻分量向该分量的一阶演化值之和刻画联系数对各等级的支持度,进而判定研究对象所处的等级,实现对研究对象的初步评价;挖掘同反分量之间的深度迁移,利用二阶偏联系数对模型进行拓展研究;最后,综合以上结果对水资源承载力进行评价分析。将模型应用于合肥市2009-2018年水资源承载力评价的结果表明：合肥市水资源承载力一直处于临界状态,但总体上呈稳中有升的态势,与以往研究结果一致,验证了本模型的合理性与有效性。与置信度阈值判别法的对比研究结果表明本文所构建的模型可以克服了一定的主观性,且具有较好的可拓展性。     

集对分析方法在区域泥石流危险性评价中的应用研究

泥石流危险性评价是泥石流灾害预报和减灾工作中的重要内容和决策基础。它是对潜灾害进行预评估的重要手段,其涉及到了致灾体的自然属性,是一个重要而复杂的科学问题。传统的泥石流危险性评价方法由于需要根据经验确定各个影响因子的权重,这在实际应用很不方便。为了解决传统方法中因子权重难以确定的问题,作者提出了基于集对分析的区域泥石流危险性评价新方法。该方法不仅可以消除应用时需要人为确定各因子权重的弊端,而且其联系度能够刻画区域泥石流危险性评价变量之间微观上的相关结构。最后将模型应用到北川县7乡镇,研究表明应用集对分析法可行的。     

联系数中i赋值的新途径及在水质评价中的应用

集对分析是针对确定与不确定问题进行定量分析的新理论,其联系数中i值具有不确定性。提出构建水质评价标准样本和"比较标准"样本集合组成集对,并针对集对分析中联系数表达式的差异度系数i取值的不确定性,采用遗传算法对差异不确定度系数i赋值,将所得的集对分析联系数表达式用于四川省8条河流的12个站点的水质评价,并与贝叶斯法评价结果相比较,结果基本一致,亦与实况相符合,从而为i值的确立和水质评价提供了一种可行的方法。     

基于集对分析的年径流丰枯分类新方法

年径流丰枯不仅与年径流大小有关,而且与年径流的时间分配有关.传统年径流丰枯分类仅考虑了年径流的大小,忽略了年径流的时程分配对丰枯分类的影响.为此,提出了年径流丰枯分类新方法--集对分析法.集对分析法考虑了径流的大小及其年内时程分配,即将年内12个月的月径流量分别分类并构造分类集合,由分类集合与分类标准集合构造集对,用联系度描述集对的关系进而进行径流丰枯分类.将集对分析法用于金沙江干流某水文站年径流丰枯分类,研究表明集对分析法概念清楚,计算简单,分类结果可信.     

石化企业火灾危险性评价研究

石化企业火灾事故时有发生,考虑到影响石化企业火灾危险性因素多具有不确定性,而集对分析可以处理确定性与不确定性问题,引入集对分析,从生产、储存、运输、消防设施与安全管理五个方面探讨石化企业火灾危险性的不确定性因素.运用层次分析法确定石化企业火灾危险性评价指标的权重,将危险性评价指标集与指标标准集组成集对,讨论基于余弦函数变化的同异反联系测度确定方法,提出基于最大联系测度的多层次综合评价方法及步骤.实例表明,该方法适合在石化企业火灾危险性评价中应用.     

区域地下水资源承载力评价的模糊联系度方法

集对分析方法中差异度系数i的取值对联系度的确定十分重要.提出将模糊联系度的思想应用到i的取值中,充分挖掘所研究系统中的有效信息,使系统评价和决策更为准确和合理.将该方法应用到实际区域地下水资源承载力综合评价中,所得结果与其它方法结果基本相同.该方法思路清晰、简便易行、合理有效,在系统评价中具有推广应用价值.     

集对分析在三峡水库汛期分期中的应用

水库分期汛限水位控制能在不增加防洪风险的条件下提高水库的兴利效益,而汛期的分期则是分期汛限水位控制的前提.介绍了集对分析理论及联系数的计算方法,以三峡水库宜昌站为例,利用统计学方法确定了洪水分期数目,并计算了汛期每一天的联系度和联系数,从而最终确定三峡水库的汛期分期.分期结果比较后表明,用集对分析方法得到的三峡水库汛期分期和其他方法的分期结果基本一致,但集对分析法原理易于理解,计算过程客观,实际使用方便,说明集对分析理论在汛期分期中的应用是可行的,值得进一步深入研究.     

流域水资源安全评价的集对分析与可变模糊集耦合模型

流域水资源安全的定量评价对进一步提高流域水资源可持续利用水平、优化产业结构、缓解水资源供需矛盾具有重要意义.在专家咨询和调研基础上确立了流域水资源安全评价的初步指标体系,用基于加速遗传算法的模糊层次分析法筛选评价指标,构建了流域水资源安全评价指标体系及其评价等级标准,提出了用集对分析方法构造流域水资源安全评价样本符合评价等级标准的可变模糊集的相对隶属度的新方法,进而利用模糊综合评价方法建立了流域水资源安全定量评价模型(SPA-QAM).SPA-QAM在巢湖流域的实证研究结果说明,该流域处于临界安全状态,必须进一步控制人口增长、推广节水农业技术、降低万元农业产值用水量,以提高该流域水资源安全保障程度.SPA-QAM综合利用了评价指标样本值与评价标准等级之间的各单指标联系度的评价信息,评价结果合理,精度高,方法直观简便,在已知等级评价标准的各类系统综合评价问题中具有一定的应用价值.