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1.
There is growing literature providing insights on the mechanism of industrial agglomeration in the transitional China. Although industries with more exports are found more agglomerated, the extent, process, and determinants of agglomeration of exporting enterprises remain under-explored due to data availability issue. Based on the Annual Survey of Industrial Firms in 2002 and 2007, this study investigated driving forces of the spatial agglomeration of exporters and the co-agglomeration of exporters and nonexporters using three digit level industries as observations. The empirical results imply that agglomeration benefits underpin the agglomeration of exporters and their co-agglomeration with nonexporters. 相似文献
2.
V.P. Mehrotra K.V.S. Sastry B.W. Morey 《International Journal of Mineral Processing》1983,11(3):175-201
Large quantities of fine coals are generated during mining and preparation stages and a significant portion of these fines is lost as refuse. Oil agglomeration shows promise of being able to minimise fine coal losses and to recover combustible matter from refuse ponds. This paper, based on a detailed literature review, presents: (a) physical-chemical and process engineering principles of oil agglomeration; (b) a comparative summary and specific process highlights of the more developed oil agglomeration processes; and (c) a critical evaluation of oil agglomeration in terms of selection of oil, process benefits and economic aspects. 相似文献
3.
Agglomeration areas in the GDR are those regions, which are characterized by an above average level of regional concentration of productive forces and their conditions of reproduction. The economic potential concentrated in these regions represents a large part of the national economy. It is possible to describe the territorial structure of these agglomeration areas by general indices (agglomeration core — agglomeration field — agglometation fringe; polycentric node-band-structure), but also the individual features of each one of these regions are to be attended. They are expressed for the first time by several forms of localization of plants and by the structure of settlements and settlement networks. The present main tendencies in the development of the agglomeration regions are: They succeeded in minimizing the regional disparities of productivity between different agglomeration regions and within them, and in stabilizing the economic position of these regions by systematic measures for investment and rationalization and the hereby influenced structural changes. At present and up to 1990 the completion of housing programme is of foremost importance by which the main activities will shift from the urban fringe to the centres of the cities; provincial towns and smaller settlements will also participate in this programme. The main target of these activities is to remove imperfect structures and other burning problems of the agglomeration regions step by step. Geographical Institutes are dealing with the management of these tasks too. 相似文献
4.
Rock 14318 is a complex microbreccia consisting of lithic fragments, chondrules, glass spherules, and glass and mineral fragments that are embedded into a fine-grained, partly glassy matrix. Rock fragmenta, chondrules, and glasses are tightly welded to the matrix and partly recrystallized, indicating a relatively high-temperature agglomeration history. Few lithic fragments have igneous textures; most are miorobreccias that have suffered various degrees of recrystallization before they were embedded into rock 14318. Compositions of lithic fragments, glasses and chondrules, in terms of compositional rock and rock suite equivalents, represent members of the ANT (anorthositic-noritic-troctolite) suite; the alkalic high-alumina basalt (KREEP) group; high-alkali quartz basalt; basalt; and dunite. The polymict nature of many lithic fragments suggests that rook 14318 require at least two, and probably more, impact episodes for its formation. Final agglomeration took place while part of the material was hot, as is indicated by the welded texture, suggesting that the final impact event was a large one, producing a fiery cloud similar to a nuée ardente. The close similarity in texture of lunar rock 14318 to certain polymict-brecciated meteorites such as Siena suggests that meteorites of this type were also formed by complex and successive impact events on the surface of the meteorite parent body, rather than during agglomeration of the parent body. 相似文献
5.
Regional and sectoral differences in the spatial restructuring of Chinese manufacturing industries during the post-WTO period 总被引：3，自引：0，他引：3
Based on the micro level data, this paper examined the spatial changes of Chinese manufacturing industries during 2002–2007. Liberalized and globalized industries are largely concentrated in the coastal region while low technology, resource-based and protected industries are widely dispersed in the inland regions. Some labor-intensive industries in the coastal region encountered congestion effects and are relocated to the central region. Statistical results indicate that industrial enterprises have significantly benefited from the geographical proximity of related enterprises. The agglomeration effects however differ across regions and sectors. The coastal region enjoys both localization and urbanization economies. The western region has no significant localization economies while the central region has no evidence of urbanization economies. The Capital Region enjoys urbanization economies to a certain degree. Both the Yangtze River Delta and the Pearl River Delta have the benefits of agglomeration. The further agglomeration in the PRD however would generate congestion effects. Although labor-intensive industries gain from agglomeration effects they are more likely to suffer from the congestion effects of related enterprises. The empirical findings indicate that agglomeration effects are not pervasive in transitional economies like China. Industrial agglomeration would contribute to productivity improvement only in a globalized and liberalized environment. 相似文献
6.
Keith Chapman 《Geoforum》1983,14(1):37-44
Most analyses of agglomeration in manufacturing evaluate the merits of clustered and dispersed spatial arrangements of plants in terms of their effects upon the profitability of individual enterprises. However, the problem of defining optimal levels of agglomeration becomes very much more acute if the costs and benefits are considered with reference to society as a whole. Examples of air and water pollution from petrochemical plants in Texas and Louisiana are used to illustrate these difficulties. It is argued that the technology and economics of pollution control have tended to reinforce the cost advantages to industry of agglomeration in large complexes despite the fact that major concentrations of polluting industries may be regarded, from a broader environmental perspective, as intrinsically undesirable. 相似文献
7.
A search for an industrial cluster in Japanese manufacturing sector: evidence from a location survey 总被引：1，自引：0，他引：1
Kazuo Kadokawa 《GeoJournal》2013,78(1):85-101
This paper explores the result of a questionnaire survey on the location decision of new manufacturing plants from 1997 to 2004 and discovers an industrial cluster in Japan. More specifically, performing an exploratory factor analysis across 22 manufacturing industries, this study firstly summarizes agglomeration advantages as a latent location factor, secondly specifies the regional share of industries that emphasize the agglomeration factor, and thirdly identifies the location of industrial cluster based on the regional share. The major finding is that there exists such agglomeration factor, by which most Marshallian location advantages are represented, and the main industrial cluster consists of high-tech industries and spread over the suburb area between Tokyo and Aichi prefectures, where are most manufacturing capacity is concentrated. 相似文献
8.
Determining factors of the development of a national financial center: the case of China 总被引：5，自引：0，他引：5
This study explores, theoretically and empirically, one of the important issues of the geography of finance, namely the location of high-level financial services. Specifically, we will try to explain why foreign financial services are spatially concentrated in a particular city so as to form a national financial center in China. By reviewing various forces behind the formation of a financial center, we argue that information problems have created the need for geographic agglomeration of financial activities based on the source of information. This is true even in an era when financial markets work through sophisticated telecommunication networks. Based on a survey of the actual location of multinational corporation (MNC) regional headquarters, and through investigation of reasons for the agglomeration of these headquarters, we anticipate that Beijing, as the prime source of policy information, is more likely than other Chinese cities to be the national pre-eminent financial center when the Chinese financial markets become more open to foreign firms in the near future. This study illustrates, using China as a case study, that geography still provides strong justification of why major financial services continue to have a high degree of spatial agglomeration in particular locations, despite the fact that the electronic transmission of information has substantially reduced the friction of distance. 相似文献
9.
T.C. Rao M. Vanangamudi K.Hanumantha Rao 《International Journal of Mineral Processing》1982,9(3):235-243
Experiments were carried out on coal fines of two different washeries, at different periods of agglomeration, to determine the size distribution of agglomerates with changes in feed size, pulp density and furnace oil dosage. It is found that the size distribution of the agglomerates follows a self-preserving growth. This behaviour has been generalised using a reduced dimensionless size axis to obtain a characteristic curve. It is shown that this curve is affected only by the nature of the feed and not by the process variables. An equation has been suggested to quantify this characteristic curve of the oil agglomeration process. 相似文献
10.
Yukio Sadahiro 《GeoJournal》2000,52(3):237-252
The present paper proposes a new method for analyzing the spatial structure of retailing, using microscale locational data
of individual retail stores. The method is based on the probability density function (PDF) of stores estimated from their
locational data, and consequently it is applicable to both micro- and macro-scale retail analyses. The PDF approach provides
a set of quantitative methods that permit us (1) to measure the degree of agglomeration, (2) to classify spatial patterns
of store location, (3) to analyze the relationship between the size and function of retail agglomerations, and (4) to analyze
the spatial structure of retail agglomeration. An empirical study is performed to test the validity of the method, and some
empirical findings are shown.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
基于腹地划分的中国城市群空间影响范围识别 总被引：6，自引：0，他引：6
城市群空间影响范围的界定是认清城市群内中心城市与腹地、城市与城市间相互关联的基础。采用主成分分析法计算中国287个地级及以上城市的结节性指数,利用累积耗费距离法和k阶数据场,综合测度了交通可达性与空间场能,根据场强"取大"原则对城市腹地进行了划分,依据城市腹地范围界定了城市群的空间影响范围。结果表明:①中国地级以上城市最大和最小结节性指数相差157.53倍,城市平均可达时间为193.43 min,场能平均值为5 412,最大和最小城市腹地相差3 751倍;②23个城市群中,空间影响范围最大的是北疆城市群,空间平均场强最大的是中原城市群;③城市群在空间上呈现为发育程度不同的"11+9+3"的分布格局和逆时针90°旋转的"β"型城市群连绵带发展格局;④基于腹地划分的城市群空间影响范围充分考虑了现实的交通网络和地形地貌特点,实现了对广域空间范围内城市腹地范围和城市群空间影响范围的定量测度。 相似文献
12.
关中城市群开采地下水有关环境地质问题
及其防治对策建议 总被引：1，自引：0，他引：1
关中城市群地下水自集中开采以来区域地下水位呈整体下降趋势,主要城市集中供水水源地水位降幅30~50 m,最大超过120 m。长期过量开采地下水引起了地下水位持续下降、地面沉降、地裂缝以及水质污染等环境地质问题。近年随着城市群限制开采量,地下水水位下降及其相关环境地质问题在局部地段有所缓和。本文以50年地下水动态监测数据为基础,针对关中城市群地下水动态特征及相关的环境地质问题进行研究分析,并对预防和缓解环境地质问题、合理开发地下水资源提出建议。 相似文献
13.
深圳珠宝产业聚集区是中国内地最大的综合性珠宝首饰加工、制造与批发中心。近年来以万山工业区为中心逐渐形成翡翠批发市场,填补了深圳珠宝产业聚集区的空白。相对于广州、揭阳、平洲、四会等成熟翡翠市场来说,深圳翡翠市场仍属于一个新兴市场。对该翡翠市场进行了SWOT（即优势、劣势、机会与威胁）分析后认为,该市场的发展潜力巨大,但其竞争压力也十分严峻;同时,也为从业者正确认识该市场的环境态势、制定正确的经营策略、提高其竞争力、为深圳翡翠市场的健康、快速发展提供一定的指导。 相似文献
14.
The intraplate activity within the Siberian Craton in the Phanerozoic is related to continental migration above the hot spot
agglomeration compared to the African superplume. The continuity of intraplate activity within this superplume testifies to
its age identity to the antipodal to the Rodinian superplume that destroyed the Rodinia supercontinent. This allowed us to
conclude that the African superplume has existed for no less than 1 Ga. Because the Rodinian and Pacific superplumes are compared,
it may be gathered that superplumes are the most long-lived deep-seated structures of the Earth. Their relation to the formation
of supercontinents probably reflects the antiphased activity caused by the thermostating effect and energy accumulation by
superplumes when being overlapped by supercontinents. When analyzing the evolution and generation of modern continents, it
is necessary to consider both processes related to the plate boundaries and the activity of superplumes determining the intraplate
magmatism therein. 相似文献
15.
S. Fred Singer 《Earth》1977,13(2):171-189
The study of the Earth—Moon system provides the connecting link between purely astronomical studies of the origin of the solar system and its planets, and geophysical and biological studies of the evolution of the Earth's geology, its surface features, atmosphere and hydrosphere, and of terrestrial life.A coherent account is presented here, based on the hypothesis that the Moon formed separately and was later captured by the Earth. The adoption of this hypothesis, together with the observed depletion of iron in the Moon, sets some important constraints on the development of condensation and agglomeration phenomena in the primeval solar nebula, which led to the formation of planetesimals, and ultimately to planets.Capture of the Moon also defines a severe heating event within the Earth, whereby its kinetic energy of rotation is largely dissipated internally by the mechanism of tidal friction. From this melting event dates the geologic, atmospheric, and oceanic history of the Earth. An attempt is made to account for the unique development of the Earth, especially in relation to Mars and Venus, its neighboring planets. 相似文献
16.
喀斯特山区碳酸盐岩土壤抗蚀性影响因素研究——以贵州毕节石桥小流域为例 总被引：2，自引：0，他引：2
对石桥小流域碳酸盐岩土壤进行理化性质分析,结果表明: 灌草丛地、水保幼林荒草地、坡耕地土壤砂粒含量依次减少,物理性粘粒含量依次增多,说明坡耕地土壤粘质化最严重;灌草丛地水稳性团粒含量最多,粒级较大,土壤水稳性最好;灌草丛地有机质含量较多,结构破坏率较低,坡耕地土壤分散率、侵蚀率、受蚀指数分别是灌草丛地、水保幼林荒草地的1. 11、1. 14, 1. 04、1. 13, 1. 87、1. 82倍,耕地土壤团聚度、团聚状况分别是灌草丛地、水保幼林荒草地的0. 83、0. 84, 0. 69、0. 64倍,说明坡耕地分散率最大,土壤团聚状况最差,土壤抗分散能力弱;小流域内土壤的容重、毛管孔隙度较我国其它地区低,约分别为1. 0g /cm3 ,和39. 86% ,而非毛管孔隙度则较我国其它地区的高,均值为25. 88%。区内碳酸盐岩土壤孔隙的这种组合特征很容易导致上层土壤粘粒向下淋失淀积,堵塞下层土壤孔隙,造成土壤上下层间饱和渗透率的显著差异,对于土壤抵抗流水侵蚀很不利。 相似文献
17.
环境空气中气溶胶粒子是由极性气体凝聚而成,呈三峰型分布.对其空气中溶胶粒子,特别是可吸入粒子的成分,气溶胶态、粒径大小、浓度等对人体健康危害进行了分析研究. 相似文献
18.
This paper examines the spatial distribution of the functional systems in the different belts of settlements around Budapest. The surburban belts have an important role in the capital's labour market, places of employment and recreation with 45 settlements. The paper reviews the structure of the Budapest agglomeration from the core to the three inner, middle and outer belts comprising the suburbs, the semi-urban settlements, the suburban villages, the satellite towns, and the satellite villages. Then the system of the functional urban centres are reviewed, The author establishes the concept of the main, the division, the district and the settlement group centres in the Budapest agglomeration. The different levels of attached functions, such as international, national, regional and local are also described with each centre type. The areal distribution of the centre system of Budapest is shown in maps too. 相似文献
19.
The coal beneficiation processes that extract coal particles using an agitated oil-water mixture may be generally termed selective agglomeration. One criticism of these processes has been that high energy inputs are needed to cause phase separation. Energy savings, however, may be obtained by the efficient emulsification of the oil phase (using say, a jet whistle emulsifier), prior to its addition to the raw coal pulp. In this work, the effect of prior emulsification on process parameters such as inversion time, product ash and recovery of organic material has been investigated for a number of different oils. Indications are that the inclusion of prior emulsification in the selective-agglomeration process will allow the exploitation of previously disregarded heavy oils. The use of these oils could bring substantial cost savings. 相似文献
20.
Alan E. Rubin 《Geochimica et cosmochimica acta》2005,69(20):4907-4918
The properties of ordinary chondrites (OC) reflect both nebular and asteroidal processes. OC are modeled here as having acquired nebular water, probably contained within phyllosilicates, during agglomeration. This component had high Δ17O and acted like an oxidizing agent during thermal metamorphism. The nebular origin of this component is consistent with negative correlations in H, L, and LL chondrites between oxidation state (represented by olivine Fa) and bulk concentration ratios of elements involved in the metal-silicate fractionation (e.g., Ni/Si, Ir/Si, Ir/Mn, Ir/Cr, Ir/Mg, Ni/Mg, As/Mg, Ga/Mg). LL chondrites acquired the greatest abundance of phyllosilicates with high Δ17O among OC (and thus became the most oxidized group and the one with the heaviest O isotopes); H chondrites acquired the lowest abundance, becoming the most reduced OC group with the lightest O isotopes.Chondrule precursors may have grown larger and more ferroan with time in each OC agglomeration zone. Nebular turbulence may have controlled the sizes of chondrule precursors. H-chondrite chondrules (which are the smallest among OC) formed from the smallest precursors. In each OC region, low-FeO chondrules formed before high-FeO chondrules during repeated episodes of chondrule formation.During thermal metamorphism, phyllosilicates were dehydrated; the liberated water oxidized metallic Fe-Ni. This caused correlated changes with petrologic type including decreases in the modal abundance of metal, increases in olivine Fa and low-Ca pyroxene Fs, increases in the olivine/pyroxene ratio, and increases in the kamacite Co and Ni contents. As water (with its heavy O isotopes) was lost during metamorphism, inverse correlations between bulk δ18O and bulk δ17O with petrologic type were produced.The H5 chondrites that were ejected from their parent body ∼7.5 Ma ago during a major impact event probably had been within a few kilometers of each other since they accreted ∼4.5 Ga ago. There are significant differences in the olivine compositional distributions among these rocks; these reflect stochastic nebular sampling of the oxidant (i.e., phyllosilicates with high Δ17O) on a 0.1-1 km scale during agglomeration. 相似文献