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基于信息熵的城市生态系统演化分析   总被引:26,自引:1,他引:25  
基于耗散结构理论和城市复合生态系统理论,构建了城市生态系统演化分析的指标体系,建立了评估城市生态系统演化的量化模型,采用基于信息熵的分析方法,可获得城市生态系统演化评估的年份信息熵和指标信息熵:采用年份信息熵计算城市系统的支持型输入熵、压力型输出压力熵、氧化型代谢熵和还原型代谢熵,分析系统的有序以及复杂性;采用指标信息熵可确定各个指标的权重,再结合各个指标的归一化值,得到综合评估得分值,作为评估城市可持续发展水平的指数值,确定系统的发展度和协调度。以宁波市为例,应用量化模型纵向评价了1996--2003年城市可持续发展进程.评价结果表明:宁波城市生态系统的健康、有序水平不断提高,协调能力不断增强,系统活力有待改善.1996--2003年,宁波城市生态系统的熵流、熵产生、总熵均呈现出下降趋势,城市发展目标逐渐明确、有序度不断增强;宁波城市生态系统熵流的发展度和协调度不断提高,表现为由较强的社会经济压力向较强的自然生态支持力转变;宁波城市生态系统熵产生的发展度呈先增后减的趋势,表明城市系统代谢功能不稳定,其协调度呈现出振荡趋势,经历了氧化型代谢→还原型代谢→氧化型代谢的转变。  相似文献   

3.
熵权多目标决策环境监测优化布点模型及应用   总被引:2,自引:1,他引:1  
熵是热力学中的重要概念,表示一个信息源发出信号状态的不确定程度。熵权表明某指标在决策或评估问题中提供有用信息量的多少,即指标的相对重要程度。本研究介绍熵权的基本概念、性质,分析其在环境监测优化布点应用中的独到之处,建立熵权多目标决策优选模型,并应用于某市大气环境监测优化布点。案例分析结果表明,该优选模型在污染因子权重分析中优选结果合理。  相似文献   

4.
小麦秸秆生物碳质吸附剂从水中吸附硝基苯的机理   总被引:3,自引:0,他引:3  
在炭化温度为300℃下,以小麦秸秆为材料制备生物碳质吸附剂,采用批量平衡试验,研究了其对水中硝基苯的吸附特性,并从动力学及热力学角度探讨其吸附硝基苯的作用机理.结果表明,硝基苯在生物碳质上的吸附过程符合拉格朗日假二级动力学方程,反应活化能为12.2 kJ/mol;吸附行为可用Freundlich吸附等温方程描述,饱和吸附容量为91.58 mg/g.由吸附热力学方程计算得到的等量吸附焓变(ΔH)<0,吸附自由能变(ΔG)<0,吸附熵变(ΔS)>0,表明生物碳质对硝基苯的吸附为放热和熵减少的自发过程.   相似文献   

5.
In the context of complex and unprecedented issues of global change, calls for new modes of knowledge production that are better equipped to address urgent challenges of global sustainability are increasingly frequent. This paper presents a case study of the new major research programme “Future Earth”, which aims to bring ‘research for global sustainability’ to the mainstream of global change research. A core principle of Future Earth is the co-production of knowledge with extra-scientific actors. In studying how the principle of co-production becomes institutionalised in the emerging structure of Future Earth, this paper points to the existence of three distinct rationales (logics) on the purpose and practice of co-production. Co-production is understood as a way to enhance scientific accountability to society (‘logic of accountability’), to ensure the implementation of scientific knowledge in society (‘logic of impact’), and to include the knowledge, perspectives and experiences of extra-scientific actors in scientific knowledge production (‘logic of humility’). This heterogeneous conception of knowledge co-production provides helpful ambiguity allowing actors with different perspectives on science and its role in society to engage in Future Earth. However, in the process of designing an institutional structure for Future Earth tensions between the different logics of co-production become apparent. This research shows how logics of accountability and impact are prominent in shaping the development of Future Earth. The paper concludes by pointing to an essential tension between being inclusive and transformative when it comes to institutionalising new modes of knowledge production in large research programmes.  相似文献   

6.
The property that power means are monotonically increasing functions of their order is shown to be the basis of the second laws not only for processes involving heat conduction, but also for processes involving deformations. This generalizes earlier work involving only pure heat conduction and underlines the incomparability of the internal energy and adiabatic potentials when expressed as powers of the adiabatic variable. In an L-potential equilibration, the final state will be one of maximum entropy, whereas in an entropy equilibration, the final state will be one of minimum L. Unlike classical equilibrium thermodynamic phase space, which lacks an intrinsic metric structure insofar as distances and other geometrical concepts do not have an intrinsic thermodynamic significance in such spaces, a metric space can be constructed for the power means: the distance between means of different order is related to the Carnot efficiency. In the ideal classical gas limit, the average change in the entropy is shown to be proportional to the difference between the Shannon and Rényi entropies for nonextensive systems that are multifractal in nature. The L potential, like the internal energy, is a Schur convex function of the empirical temperature, which satisfies Jensen's inequality, and serves as a measure of the tendency to uniformity in processes involving pure thermal conduction.  相似文献   

7.
自然界中的能量与物质系统的运动是遵循热力学定律的.从熵的角度来看,现在人类开发利用资源的方式,使系统熵增加速,不利于环境系统的有序和稳定.而人类作为智慧圈的主体,是可以通过智慧和知识,向其输入负熵,以延缓熵增速度.目前的形式下,可以采取适当的对策,坚持科学的发展观,实行节约型经济模式,从熵的角度出发寻找高效的新能源,充分利用不可逆过程的建设性作用,通过知识技术的进步提高资源能源的利用率.  相似文献   

8.
基于信息熵的乡村生产空间系统演化及其可持续发展能力   总被引:6,自引:2,他引:4  
乡村生产空间系统演化是乡村生产空间系统内部及其与外部系统间进行物质、能量和信息交换的表征或结果,这一结果的优劣是实现系统可持续发展的内生物质基础与保障。以重庆市为研究区,以2001-2015年为研究时段,基于信息熵,从支持型输入熵、压力型输出熵、氧化型代谢熵、还原型代谢熵四个方面构建乡村生产空间系统演化指标体系,揭示乡村生产空间系统的演变规律和可持续发展能力,探析乡村生产空间系统熵变与可持续发展能力之间协同演化过程中的相关关系,设计乡村生产空间系统优化路径。结果表明:(1)2001-2015年重庆市乡村生产空间系统熵流为0.017~-0.049,熵产生为0.204~0.059,均呈下降趋势,乡村生产空间系统的协调性和活力得以增强;总熵变为0.221~0.010,呈相同趋势,乡村生产空间系统有序度不断提高,总体上向健康水平发展。(2)2001-2015年重庆市乡村生产空间系统可持续发展能力得分为1.285~2.803,呈上升趋势,系统可持续发展态势良好,并不断向可持续方向演进。(3)可持续发展能力得分与支持型输入熵、还原型代谢熵正相关,与压力型输出熵、氧化型代谢熵负相关,与熵流、熵产生和总熵变负相关。  相似文献   

9.
为了研究环丙沙星(Ciprfloxacin,CIP)在土壤中的吸附过程及主要影响因素,以川西北高原亚高山草甸土和沼泽土为研究对象,采用OECD guideline 106批平衡方法,分析了亚高山草甸土和沼泽土对CIP的吸附动力学特征、吸附热力学特征以及pH、温度、CIP初始浓度等对其吸附过程的影响.结果表明:①不同初始浓度CIP在两种土壤中的吸附过程均符合准二级吸附动力学模型,R2为0.920 2~0.988 6.②Freundlich等温吸附模型能够较好地拟合两种土壤对CIP的吸附热力学过程,吸附等温线符合“L”型.③在15~35℃范围内,吸附热力学参数ΔHθ(吉布斯自由能)和ΔGθ(焓变)均小于0,ΔSθ(熵变)大于0,表明两种土壤对CIP的吸附过程以物理吸附为主,属于吸附体系混乱度增加的自发进行的放热反应.④吸附容量lg Kf满足沼泽土大于亚高山草甸土,说明沼泽土对CIP的吸附能力强于亚高山草甸土,且两种土壤的吸附能力与CIP的初始浓度呈正相关.⑤在pH为3~9条件下,吸附量均随pH的增加呈现先增后减的趋势,当pH为5时,两种土壤对CIP的吸附效果均最好,表明强酸和碱性环境均不利于土壤对CIP的吸附.研究显示,CIP在两种土壤中的吸附容量、吸附强度以及吸附速率均存在较大差异,温度、CIP的初始浓度和pH对两种土壤吸附CIP存在一定影响.   相似文献   

10.
景观生态学及熵模型在荒漠化监测与评价中的应用   总被引:1,自引:1,他引:0  
在对景观生态学和"熵"的概念及其特征进行分析的基础上,以承德市北部荒漠化地区为例,重点讨论了景观生态学中优势度指数、均匀度指数以及热力学中熵模型在荒漠化土地动态变化及评价中的应用.根据2001年8月31日Landsat卫星遥感TM数据,结合现场调查,通过景观熵值、植被覆盖度等指标综合评判,对研究样地荒漠化程度进行划分.结果表明:通过熵模型计算荒漠化景观系统的熵值,可以判断荒漠化景观发展趋势,也可以比较不同荒漠化景观的荒漠化程度.经过综合指标分析,判定丰宁县小坝乡属于重度荒漠化地区,围场县御道口属于中度荒漠化地区,该结论与实际相符合.   相似文献   

11.
IntroductionSorptionofanorganicpollutanttosoilhasamajorinfluenceonitstransport,bioavailabilityandfateinnaturalenvironmentsanddevelopingsoilpollutionremediationtechnologies .Extensiveresearch(Chiou ,1979;1983;1985 ;1998a ;Karickhoff,1979;Kile ,1995 ;Rutherford ,1992 )suggestedthatsorptionofnonionicorganiccompounds(NOCs)fromwatertosoilisdueprimarilytothepartitioningintosoilorganicmatter(SOM ) .AdsorptionofNOCsfromwaterbyrelativelypolarsoilmineralsissuppressedbythestrongcompetitiveadsorption…  相似文献   

12.
The formation of ordered structures seems to contradict fundamental principles of physics according to which disorder should ever increase. Synergetics deals with the question how in spite of these laws structures can arise. We shall give a number of explicit examples. Large classes of ordered states in open systems are determined by a new principle based on the growth rates of collective configurations. In contrast, concepts such as entropy or entropy production are inadequate to treat such phenomena.  相似文献   

13.
为了解兽药抗生素在西北黄土中的吸附行为及机制,以环丙沙星(Ciprfloxacin,CIP)为目标污染物,采用批平衡实验法研究其在黄土中的吸附动力学、吸附热力学、pH值和粒径等影响因素.结果表明:环丙沙星在黄土中的吸附可分为两个阶段,6h内表现为快速吸附,6~10h表现为慢速吸附,10h后吸附达到平衡;环丙沙星在黄土中的吸附动力学过程较符合准二级吸附动力学模型,吸附速率受颗粒内部扩散和外部液膜扩散共同影响;吸附热力学过程较符合Freundlich等温吸附模型,且吸附等温线符合L-型,表明黄土对环丙沙星的吸附受溶液中溶质和水分子共同作用影响;焓变ΔHθ、熵变ΔSθ和吉布斯自由能ΔGθ均<0,表明黄土对环丙沙星的吸附是混乱度减少的自发进行的放热反应;pH=5时黄土对环丙沙星的吸附量最大,pH值为2~5时,黄土对环丙沙星的吸附量随pH值升高呈上升趋势,pH>5时,黄土对环丙沙星的吸附量随pH值升高呈下降趋势,表明强酸和碱性环境均不利于吸附;吸附量与黄土粒径呈反比,与初始浓度呈正比.由实验结果推断黄土对环丙沙星的吸附主要与有机质含量有关,主要吸附机制为环丙沙星分子中氨基的阳离子交换作用.  相似文献   

14.
Numericalmodelingofradionuclidemigrationinporousmediawithnonequilibriumsorption¥ChenJiajun;DaiJie(DepartmentofEnvironmentalEn...  相似文献   

15.
三峡库区(重庆段)是典型的河道型水库生态脆弱带,生态系统本底条件较差.明确库区生态系统健康状况及其胁迫因子,对促进库区可持续发展、维护三峡库区生态安全具有重要的现实意义.针对三峡库区(重庆段)目前的生态系统特点,构建了自然-社会-经济复合生态系统健康状况评价指标体系,并在灰色系统理论基础上,将信息论中Jaynes最大信息熵原理引入到生态系统健康评价当中,对三峡库区(重庆段)复合生态系统健康进行了评价.结果表明,三峡库区(重庆段)生态系统正处于急剧变化的过渡阶段,生态系统的生产、调节和服务功能分异明显.三峡库区(重庆段)生态系统东段的健康程度总体上好于西段,但东段内部空间分异明显,结构复杂.针对三峡库区(重庆段)现存的生态环境问题,提出了相应的调控措施和途径.  相似文献   

16.
为了对黄姜皂素产业主要生产工艺进行综合分析,找出最优生产工艺,建立了基于博弈论组合赋权的多准则妥协解排序(VIKOR)黄姜皂素生产工艺评价模型.首先,利用熵值法对原始数据进行分析,确定各评估准则的客观权重;然后,通过博弈论模型对主客观权重进行科学化组合,得到综合权重;最后,将该模型运用在黄姜皂素产业主要生产工艺的评价上,得到了4种生产工艺的综合排序.研究结果表明:博弈论组合赋权的VIKOR模型对4种生产工艺的评估结果与利用其他评估模型所得结果一致,该模型能全面考虑各项评估准则及评估对象与最优工艺和最劣工艺的关系,评估过程更为科学、完整;同时,其计算过程简洁,提高了评估效率.  相似文献   

17.
To meet the increasing need for practical life-cycle thinking in manufacturing, this paper proposes a method that includes the life-cycle perspective in manufacturing decision making. This method combines discrete-event simulation (DES) – commonly used for the conceptual evaluation of manufacturing systems – with life-cycle assessment (LCA). This combination captures the dynamic interrelationships between manufacturing processes in order to analyse systemic responses to configuration changes, something static LCA modelling cannot do. The method evolved when a bearing production line at SKF was being examined to relate manufacturing decision making to environmental consequences. This was done using DES to investigate how parameters normally used to optimize traditional manufacturing system performance influence energy use and material losses in manufacturing systems. The environmental consequences of this material loss and energy use are further calculated using LCA methodology. Results indicate that while the combination of the two methods increases the data collection workload, it uncovers previously hidden environmental consequences of manufacturing decision making and introduces a way to assess an industrial actor’s manufacturing system using relevant LCA scenarios.  相似文献   

18.
Through human history, wealth has been measured in grain, gold, and, now, dollars. Though counterfeiting of coins and notes goes back a long way, it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our Earth and ourselves. Various schemes using analysis of utility functions, oil equivalents, entropy, energy, and other units have been tried and, while helping to understand some basic processes and flows, have always been swamped by the machinations of financiers and the attention big sums of money attract. Now, the concept of exergy, pioneered in Eastern Europe in the 1950s, is being researched, developed, and applied, especially in China, driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises. A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not sustainable. Without that understanding, any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.  相似文献   

19.
凹凸棒石/氧化锌纳米复合材料对亚甲基蓝的吸附性能   总被引:5,自引:1,他引:4  
采用化学沉淀法在凹凸棒石的表面负载纳米氧化锌合成了凹凸棒石/氧化锌(ATP/ZnO)纳米复合材料.同时,研究了亚甲基蓝在纳米复合材料上的吸附行为,并从热力学和动力学角度探讨了吸附作用机理.吸附实验表明:纳米复合材料对亚甲基蓝有优异的吸附能力;纳米复合材料对亚甲基蓝的吸附热力学符合Langmuir等温吸附方程,最大吸附量可达110.50mg·g-1,吸附焓变为18.69kJ·mol-1,吸附自由能变为-33.06~-22.74kJ·mol-1,吸附熵变约为146J.mol-1.K-1,是一个自发的吸热过程;纳米复合材料对亚甲基蓝的吸附动力学符合准二级动力学方程,速率常数随着溶液初始浓度的提高而下降.  相似文献   

20.
Delft University has an established track record in educating MSc students the art of designing chemical processes and products. To foster its future position an experimental conceptual design program has been set up. In this program sustainability requirements are used to stimulate creativity. Our vision is that (designs of) processes, products and systems should fit in a sustainable technological world (STW). The STW is in balance with the other great cycles on Earth, being the exchange of water between hydrosphere and atmosphere and the exchange of carbon dioxide between atmosphere and biosphere. The STW has, like the biosphere and hydrosphere, a certain upper mass (110 Gton) and energy (8800 GW). The STW itself is evolutionary and cannot be designed, yet its content—technological artifacts—is designed. Newly designed artifacts requiring an average life span of 25 years (one human generation), should fit the STW. The total annual product renewal of the STW is 4.4 Gton/year and the energy consumption 64 MJ/kg. These numbers total both industrial production as well as energy spent by consumers using the artifacts. Conceptual designs of chemical processes should fit in this concept of a STW. This means that processes requiring a high energy level are subject to change, for they limit society's patterns of energy consumption. Chemical processes demanding a lot of chemical energy are reduction processes: primary processes (roasting ores and biomass) and secondary processes (dissociations and dehydrogenations). In this article a conceptual design of both types of processes is presented. The first results show that their energy consumption fits the STW and points towards new design solutions for chemical processes, new applications of chemical products and new relationships with other technological sciences.  相似文献   

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