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1.
本文利用波特五力模型对中国风电产业所处竞争环境进行分析,认为中国风电产业内部竞争激烈,外来威胁不明显,替代品威胁力较弱,产业链上游核心零部件生产呈现"技术空心化"。通过对"风电零部件供给-风电整机制造-风电场运营开发"整个风电供需链的分析,认为现阶段制约我国风电产业持续发展的最大障碍,并不在于风电的制造、生产和运营,而是受制于风电并网的约束。为进一步研究未来我国风电市场的发展趋势,本文基于预测效果优于BP神经网络的STA-LSSVM模型,利用1993-2011年中国风电装机新增容量、累计容量及风电并网新增容量、并网累计容量等数据,预测了风电生产供给与风电并网需求的发展趋势。结果显示,2012-2015年我国风电装机容量增长率逐年上升趋势明显,而风电并网容量增长率则趋于平缓。预计到2014年风电累计并网容量缺口将达到4 817.03 MW,需求缺口将愈来愈大,风电消纳远远滞后于风电生产,风电产能"相对过剩"的局面将更加严重。鉴于此,本文在政策层面上给出如下建议:(1)进一步加强国家电网建设。要有重点、分步骤地建设偏远地区电网设施,并建立更大区域的电力市场,在区域电网内甚至在区域电网外寻找风电消纳市场;(2)创新风电并网技术及应用。政府应积极支持风电开发和并入电网所需要的输电投资;(3)加强风电项目风险控制。国家电力监管部门要重视风电场与电网的相互影响,加强监管力度;(4)创新风电利用方式。通过开发供热、农业提水灌溉等灵活用电负荷,促进风电就地消纳和利用。  相似文献   

2.
环境规制会影响产业集中度吗?:一个经验研究   总被引:2,自引:0,他引:2  
作为刻画产业结构的重要指标之一——产业集中度,一直受到国内外学者的广泛重视,但鲜见有学者研究环境规制会对产业集中度带来何种影响。为了对此进行研究,本文以我国工业部门1996-2006年的数据为样本,首先计算出产业集中度(CR4和CR8)水平,并运用面板数据分析方法,在控制相关变量的基础上,研究了环境规制对产业集中度带来的影响,得到以下结论:(1)在不考虑其他控制变量时,环境规制变量对产业集中度产生不显著的正向促进作用,但随着控制变量的逐步引入,环境规制变量的显著性水平逐步提高,模型总体拟合效果趋于优化;(2)同时,进入退出壁垒、利润率水平、经济干预政策和规模经济程度四个控制变量也会对产业集中度产生显著的正向推动作用。因此,适度强化环境规制水平,不仅有利于保护环境,优化资源配置,淘汰落后产能,解决结构性产能过剩,而且有利于提升产业集中度,增强我国企业在国际上的竞争力。  相似文献   

3.
在STIRPAT模型的基础上,通过加入能源消费需求、工业化水平和产业集聚度变量,建立了拓展的STIRPAT模型,并使用动态面板GMM方法,分析了我国30个省会城市和直辖市2003-2012年间的面板数据,指出不同的城市规模与集聚程度会对空气质量有不同的影响。首先。从总体上来说,城市人口规模、富裕程度和技术水平是影响城市空气质量的主要因素,其中人口规模和技术水平对空气质量的影响均为正效应,而富裕程度对空气质量的影响呈现出倒N型EKC曲线形状;较高的能源消费需求和工业化水平会恶化空气质量,而较高的技术水平和产业集聚度会改善空气质量,这表明相关部门可以从不断提高科技水平和产业集聚度入手,通过各种方法减少能源消费需求、降低工业化水平。来达到改善空气质量的目的。其次,在总体回归的基础上,本文重点按照人口规模、经济规模和经济集聚度、人口集中度分析了城市规模与集聚对空气质量的影响情况。结果表明:欠发达城市和大中城市的回归结果与总体回归结果一致,而经济发达城市和特大城市的回归结果与总体回归结果有一定差异,本文认为导致这些差异的主要原因是科学事业费支出方向、社会消费品结构以及工业清洁能源利用及其利用效率等因素;低产业集聚度和低人口集中度城市的情形与总体较为相近,而高产业集聚度和高人口集中度城市的EKC曲线形状与工业化水平系数与总体结果相反,这两种差异分别与城市的发展阶段和城市的人口素质有关。因此,城市的相关部门在追求规模经济的同时应该注重科技投入结构的改善,注重提高能源使用效率和清洁能源的使用率,并且在不断提高产业集聚度与人口集中度的同时追求绿色GDP的实现,注重人口的文化教育以提高人口素质,从而提升公众的环保意识,以抵消随人口集中度提高带来的环境压力。  相似文献   

4.
武汉城市圈制造业集聚的实证研究   总被引:1,自引:0,他引:1  
采用调整后的产业集聚EG指标,结合产业集中度指数,对武汉城市圈2000~2007年制造业19个行业的集聚程度进行了精确的测度,并分别从制造业集聚度变动趋势、产业集聚度特征、产业集聚空间分布特征、增长集聚弹性等角度进行了详细的分析。结果表明:考察期间武汉城市圈制造业的区域集聚度较高,而且中高技术行业集聚特征十分明显,资源性和低技术行业较为分散;从行业的区域集聚空间分布特征来看,产业集中度较高,主要集中在武汉、黄石、孝感和黄冈4市,其它5个城市产业集中度较低,城市上榜次数较少,且上榜行业主要集中在资源性和低技术行业,形成了以武汉等4市为中心,其它5市为外围的“中心 外围”结构;构建的产业集聚弹性模型计算结果表明,整体上城市圈制造业集聚弹性较大,但不同行业间的弹性值差距明显。  相似文献   

5.
中国环境污染密集型产业脱钩的异质性及产业转型   总被引:1,自引:0,他引:1  
根据现有文献,研究中国的经济增长与环境污染的脱钩,需要将不同环境密集型产业与经济增长的关系分别测算,然后进行比较。本文选取了工业污染的三大来源——废水、废气和固体废物,每种污染源对应着一类环境密集型产业。这三种产业密集排放的污染物的量与经济增长之间的脱钩关系及其内在机制,这是本文研究的重点。本文借鉴Tapio弹性分析模型构建了我国经济增长与不同环境密集型产业之间的脱钩状态的分析模型,并对脱钩状态和程度的判定标准做了规定。随后,对2001-2009年四个时期的经济增长与不同环境密集型产业集中排放的污染物的量之间的脱钩指数进行了测算,同时测算了各产业污染的工业产值弹性及其工业产值的GDP弹性,并对脱钩状态和程度做了判定。结果表明:三类产业的脱钩程度各不相同,其动力机制与发展前景也有所不同,因而需要有针对性地采取规制和治理措施。  相似文献   

6.
以大华北地区2000-2012年的天然气消费数据为样本,采用对数线性需求函数模型,分别估算了引入价格规制变量和不引入时的大华北地区需求弹性模型,并分析了价格规制对模型估算结果的影响。考虑到需求弹性的差异性问题,文章选取北京、山东、陕西和甘肃四个地区为研究对象,分别估算得到对应地区需求弹性模型,结合区域市场特点具体分析了产生差异的原因。为探究价格规制对天然气区域市场的影响,由大华北地区需求弹性模型分别估算了考虑价格规制影响和不考虑两种情形时该地区2009-2012年每年的天然气需求函数,同时对大华北地区在继续实行价格规制和放宽规制两种情形下未来的天然气需求进行了预测分析。研究表明:大华北地区天然气需求价格弹性为负、需求曲线向下,缺乏价格弹性,富于GDP弹性,GDP的持续增长是拉动天然气需求的最大动力;不同天然气区域市场,需求价格弹性、GDP弹性、价格规制弹性都存在很大的地区差异性,通常地区经济水平高、用户价格承受力强时,区域市场需求价格弹性较小,GDP弹性较小,价格规制弹性也较小,反之亦然;考虑价格规制时的大华北地区天然气需求曲线较不考虑时陡峭需求价格弹性与GDP弹性均小于不考虑情形,价格规制降低了需求价格弹性,抑制了GDP弹性;价格规制政策拉高了天然气需求,大华北地区未来市场具有支付意愿的天然气需求小于价格规制政策拉高的市场需求,为扩大天然气价格市场化后的需求,地方政府可考虑对地区市场采取一定的价格补贴措施来拉动需求。  相似文献   

7.
中国天然气产业的最大特点是垄断程度较强,政府对天然气产业的各个环节均存在价格管制。鉴于此,本文通过构建CGE模型以期全面量化分析政府对天然气产业价格管制政策变动产生的影响,从而为政府制定决策提供可供借鉴的依据。与以往的研究不同,本文构建的静态CGE模型,不仅刻画了天然气产业非完全竞争的市场结构还刻画了政府对天然气产业的价格管制行为。运用该模型,本文分别从消费侧以及供应侧的角度模拟了政府对天然气产业价格管制政策变动对我国碳排放及经济的影响,并且从经济结构以及能源消费结构的角度进一步分析了天然气价格管制政策变动的二氧化碳排放机制。模拟结果表明:1消费侧价格管制。提高天然气价格能够通过产业结构调整以及能源消费结构调整降低经济主体对天然气的消费进而降低二氧化碳的排放,同时由于天然气市场规模的缩小导致天然气产业的超额利润率有所下降。提高天然气价格提高了居民消费价格指数(CPI),降低了实际GDP以及居民福利水平。降低天然气价格对二氧化碳排放的影响、传导机制以及经济影响与提高天然气价格产生的影响类似,但是作用效果基本上相反。2供应侧价格管制。取消天然气供应侧价格管制能够通过优化要素配置促进实际GDP的增长、居民福利水平的改善并且降低居民消费价格指数(CPI),在收入效应的作用下不仅提高了经济主体对天然气的消费还提高了对能源总量的消费,从而增加了二氧化碳排放,同时由于天然气市场规模的扩大促进了天然气产业超额利润率的增长。因此,应该逐渐建立完善的天然气价格管理体制,确保天然气资源的有效利用;对天然气产业超额利润率进行管控,避免产生较大的负面收入分配效应;逐步取消天然气供应侧的价格管制,打破行政垄断,引入市场竞争机制,推动天然气产业的市场化进程。  相似文献   

8.
在产业转型和贸易开放深入开展的同时,我国的劳动力市场波动也出现了明显的变化。通过推导基于垄断竞争的劳动需求模型、利用我国1998-2007年工业企业数据库检验产业转型升级中劳动市场波动是否加剧,并进一步考察贸易开放对两个产业部门的劳动市场波动差异的影响。实证研究发现,当外生冲击致使工资价格上升(或降低)1%时,高技术部门劳动需求将减少(或增加)0.265%-0.272%,而低技术部门企业的劳动需求将减少(或增加)0.258%-0.260%,高技术产业部门的劳动需求比低技术部门更富有弹性,意味着产业升级过程中劳动者将面临增大的就业风险和收入波动;进一步地,产业转型中的劳动市场波动加剧将在贸易开放背景下进一步扩大,且该结论具有稳健性。该实证发现为我国产业调整下完善劳动力市场提供有价值的政策启示,如组织开展劳动权益监督、鼓励劳动者参加职业技能培训以提高劳动者的谈判地位,针对高技术企业劳动群体建立就业预警、救助和帮扶机制,熨平就业过程中面临的经济、精神和生活上的波动。  相似文献   

9.
近年来,碳排放逐渐从环境问题演变成政治经济问题,碳关税是发达国家推崇的新型贸易壁垒,以此来增强本国产业竞争力,这对于碳排放量较大的发展中国家无疑会产生较大的不利影响。为了提前做好准备应对发达国家碳关税,以我国出口结构中高碳产品最密集的制造业为对象,研究碳关税措施和出口贸易行业结构之间的关系,在气候变化问题和国际贸易两大体系之间建立关联。本文首先构建碳关税的局部均衡模型,从几何分析和数理分析两个维度出发,探讨美国征收碳关税对我国制造业出口贸易和社会福利产生的影响。在此基础上利用GTAP模型,模拟美国、欧盟等发达国家在四种情境下征收碳关税的情况,分析实施碳关税对我国制造业各行业出口结构的影响,以及对我国社会福利的影响。研究结果表明:美国征收碳关税会导致我国制造业产品出口市场价格下降,出口量减小;我国开征国内碳税会导致制造业产品出口市场价格上升,出口量减小,但出口减小幅度低于美国对我国制造业征收碳关税时的出口减小幅度;美、欧等发达国家征收碳关税将导致我国化工橡胶制品行业、石油煤炭加工工业以及造纸业等能源密集型行业的出口减少,其中受到冲击最严重的行业为造纸业,出口降幅在1.79%-6.05%之间,而其他非能源密集型的制造行业出口增加;我国制造业出口结构在一定程度上得到优化;我国整体福利水平下降,下降水平在21.34亿-83.47亿美元之间。最后,从国际协调、出口结构调整、绿色制造发展等方面提出对策建议,为我国制造业的发展提供借鉴。  相似文献   

10.
基于耗散结构系统熵模型的产业有序发展研究   总被引:2,自引:0,他引:2  
"熵"和系统有序性之间存在着密切的关联关系,系统熵值的变化代表着系统有序发展程度的变化。对于封闭状态下的耗散结构系统来说,其内部要素之间的相互作用,会使系统的熵值增加,系统运行开始变得不稳定。具体表现为围绕目标而有效运行的秩序受到破坏,出现控制失灵、功能紊乱的无序现象。由此,构造耗散结构系统熵模型并测量系统熵值的变化,就可以有效反映系统运行的有序程度。本文研究发现,产业系统是一个典型的耗散结构系统,其发展的有序度可以用静态意义上的"结构熵"和动态意义上的"运行熵"来反映。因此,建立产业系统熵分析模型,进而解析产业系统的"结构熵"和"运行熵",可以有效解决产业系统有序发展程度的测定问题。利用我国风电产业发展的相关数据进行实证分析发现:在我国风电产业超高速发展的背后隐藏着一定程度的无序性,但随着产业整合的不断推进,其结构有序度将得到提高,运行有序度开始有所改进。  相似文献   

11.
Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources.  相似文献   

12.
In early 1980 an extension agent was assigned to the rural municipality of Bangui, Ilocos Norte, Philippines to work on development projects – in particular the improvement of the supply of safe water for drinking and sanitation. After many months of visiting spring sites and meeting with community leaders, a small part of the municipality was selected to build a gravity fed piped water system. Although the system took many months to plan, identify funding and construct, the 600 community members were ultimately rewarded with house to house connections that enabled them to achieve per capita water consumption levels above the minimum levels recommended by the World Health Organization. Of course, money was critical to ensure the project’s success, but many other factors played an equally critical role. For instance, without the active participation of the community and the unwavering support of the community leadership the project would not have survived the initial planning stage. Also, the extension agent played a critical role by acting as a conduit between funding agencies, the Bureau of Public Works and the community. The primary lesson to be learned from this experience is that the success of rural development projects is largely driven by the synergy between the community, technical support, financial support, and agents of change such as extension agents. If any of these ingredients had been lacking, the project result would likely have been far different.  相似文献   

13.
14.
It is known that pseudoviviparous plant taxa are most numerous in the Arctic and high mountain regions, where they sometimes account for a noticeable part of the local flora and play an important phytocenotic role. The complex of pseudoviviparous taxa is an interesting model for investigating the processes of hybridogenic speciation, as various mechanisms stabilizing the hybrid genetic systems proved to be effective in them. In particular, this concerns vast and taxonomically complex groups such as the genera Deschampsia, Festuca, and Poa.In this paper, published data on the taxonomy, chromosome numbers, and distribution of pseudoviviparous grasses in the Arctic regions and subarctic mountain systems are reviewed.  相似文献   

15.
16.
Polybrominated diphenyl ethers (PBDE) are used as flame retardants in a wide variety of products. As part of the Integrated Exposure Assessment Survey (INES), this study aimed to characterize the exposure of an adult German population using duplicate diet samples, which were collected daily over seven consecutive days, and indoor air and house dust measurements. Our study population consisted of 27 female and 23 male healthy subjects, aged 14–60 years, all of whom resided in 34 homes in southern Bavaria. In these 34 residences the air was sampled using glass fiber filters and polyurethane foams and the dust was collected from used vacuum cleaner bags.The median (95th percentile) daily dietary intake of six Tetra- to HeptaBDE congeners was 1.2 ng/kg b.w. (3.3 ng/kg b.w.) or 67.8 ng/day (208 ng/day) (calculated from the 7-day median values of each study subject). Concentrations in indoor air and dust (cumulative Tri- to DecaBDE congener readings) ranged from 8.2 to 477 pg/m³ (median: 37.8 pg/m³) and 36.6 to 1580 ng/g (median: 386 ng/g), respectively. For some congeners, we identified a significant correlation between air and dust levels.The median (95th percentile) blood concentration of total Tetra- to HexaBDE congener readings was 5.6 (13.2) ng/g lipid. No significant sex differences were observed, but higher blood concentrations were found in younger participants. Using a simplified toxicokinetic model to predict the body burden from exposure doses led to results that were of the same order of magnitude as the measured blood concentrations.Based on these measurements and given our exposure assumptions, we estimated for the total tetra- to heptabrominated congener count an average (high) comprehensive total daily intake of 1.2 ng/kg b.w. (2.5 ng/kg b.w.). Overall, our results suggest that dietary exposure is the dominant intake pathway at least in our study population, responsible for 97% (average intake) and 95% (high intake) of the total intake of an adult population.  相似文献   

17.
This paper presents a new general, process-based river model for substances such as radionuclides from single pulse fallouts. The new model has been critically tested using data from 13 European rivers contaminated by radiocesium from the Chernobyl accident. This modelling approach gives radionuclide concentrations in water (total, dissolved and particulate phases; and also concentrations in sediments and fish, but the latter aspects are not discussed in this paper) at defined river sites. The model is based on processes in the upstream river stretch and in the upstream catchment area. The catchment area is differentiated into inflow ( approximately dry land) areas and outflow ( approximately wetland) areas. The model also accounts for time-dependent fixation of substances in the catchment. The catchment area sub-model is based on a previous catchment model, which has been tested with very good results for radiocesium, radiostrontium and Ca-concentrations (from liming operations). The new river model is simple to apply in practice since all driving variables may be readily accessed from maps and standard monitoring programs. The driving variables are: latitude, altitude, continentality, catchment area, mean annual precipitation, soil type (percentages or organic and sandy soils), fallout and month of fallout. Modelled values have been compared to independent empirical data from 10 rivers sites (91 data on radiocesium in water) covering a wide domain (catchment areas from 4000 to 180 000 km(2), precipitation from 500 to 960 mm/yr and fallout from 1700 to 660 000 Bq/m(2)). The new model predicts very well--when modelled values are compared to empirical data, the slope is perfect (1.0) and the r(2)-value is 0.90. This is good giving the fact that there are also uncertainties in the empirical data, which set a limit to the achieved predictive power, as expressed by the r(2)-value.  相似文献   

18.
Harvesting of non-timber forest products is an integral component of rural livelihoods throughout the developing world. At times this is at odds with conservation objectives. Reconciliation of the two requires examination of local level contexts and needs. This paper reports on the harvesting needs for Ischyrolepis by a rural community in South Africa, against the setting that they had recently been prohibited from harvesting by the local conservation officials. Interviews were conducted with conservation officials to understand the reasoning for the prohibition. Local demand for Ischyrolepis was assessed by household surveys, as well as in-depth interviews with traders. The density and size class distribution of Ischyrolepis was determined using transects. The total annual demand for Ischyrolepis was determined to be approximately only 2.7% of the standing crop. The bulk of the annual demand was for small-scale trade, the income from which was a primary source of income for the few harvesters. Very little evidence could be found indicating that harvesting was damaging the resource or its habitat, and local knowledge suggested that the abundance of the species was stimulated by harvesting. Even if market demand were to increase, the size of the shoots required means that less than 20% of the standing crop could be harvested annually. Current regulations around harvesting are in a state of revision, and hence confusion prevails regarding if harvesting is permissible, and if so, under what conditions, which is detrimental to both conservation and livelihoods. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

19.
Studies have been carried out to determine the natural radioactivity in some building materials (bricks, tiles, marble and ceramics) and their associated radiation hazard. The radioactivity concentrations of 226Ra 232Th and 40K were measured using a gamma spectrometer with a Hp–Ge detector. The activities of 238U and 234U were measured using an alpha-spectrometer with a surface barrier detector after applying a radiochemical procedure. The 234U/238U isotopic ratios were calculated. The radium equivalent activities and the radiation hazard index associated with the natural radionuclides were calculated. A computer program was developed and applied to calculate the dose rate a person will receive from the walls of a room constructed from the studied building materials.  相似文献   

20.
The World Summit on Sustainable Development (WSSD), held in Johannesburg during 26 August and 4 September 2002, was a truly remarkable event, not least because it identified and committed the world community to what has to be done to realise Agenda 21 objectives. Discussion begins with the "means of implementation" of the Johannesburg Plan of Implementation (JPI). Education for, and raising awareness of, sustainable development are the key commitments in the "means of implementation". The issues central to these commitments are discussed. The crucial role of moral philosophy in education for sustainable development is then discussed. Defining the "problem" as lack of progress (in fact negative progress between Rio and Johannesburg) towards global sustainable development, a cause–effect relationship of the "problem" is developed based on a systematic and logical analysis. It shows that the "cause" is West's profoundly materialistic, environment-degrading and exploitative attitude and activities to satisfy grossly unsustainable, hedonistic and insatiably avaricious Western life-styles – life-styles that are held up by the West as "ideal" fruits of economic "development" to be aspired by all. The "effects" are pollution of air, water and soil; mounting loss of biodiversity, ecosystems and species; relentlessly widening north–south divide, etc. It is argued that while science and technology can address some of the "effects", they cannot address the "cause". Only moral philosophy can by fundamentally re-orienting moral values genuinely to respect nature and the environment. Based on sound and tested principles of Educational Psychology, a proposal is then made for including moral philosophy in the formal curricula (content and pedagogy) of primary, secondary and higher education for instilling in children and young people genuinely environment-respecting moral values. To this end a generic syllabus for the secondary level is proposed. Finally, it is argued that if the scientific community really believes that science or technology alone can radically change the pervasive environment-degrading moral values to those that genuinely respect the environment, thus paving the way to real global sustainability, then it must demonstrate how this could be done and explain why, despite their abundant science and technology, the developed nations are the biggest polluters and consumers with grossly unsustainable life-styles. Certainly, examples would be much more convincing than rhetoric or tired old clichés about how science and technology alone could deliver global sustainable development.  相似文献   

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