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1.
This paper investigates the relationship between economic growth, carbon dioxide (CO2) emissions, and energy consumption with an aim to test the validity of the Environmental Kuznets Curve (EKC) hypothesis in five ASEAN (Association of South East Asian Nations) countries (Indonesia, Malaysia, Philippines, Singapore, and Thailand) by applying the panel smooth transition regression (PSTR) model as a new econometric technique. The PSTR model is more flexible and appropriate for describing cross-country heterogeneity and time instability. Our empirical results strongly rejected the null hypothesis of linearity, and the test for no remaining nonlinearity indicated a model with one transition function and two threshold parameters. The first regime (levels of GDP per capita below 4686 USD) showed that environmental degradation increases with economic growth while the trend was reversed in the second regime (GDP per capita above 4686 USD). The results also showed that energy consumption with either the first or the second regime lead to increase CO2. The overall results support the validity of the EKC hypothesis in the ASEAN countries. 相似文献
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3.
A Lattice Approach to Image Segmentation 总被引:1,自引:0,他引:1
Jean Serra 《Journal of Mathematical Imaging and Vision》2006,24(1):83-130
After a formal definition of segmentation as the largest partition of the space according to a criterion σ and a function
f, the notion of a morphological connection is reminded. It is used as an input to a central theorem of the paper (Theorem
8), that identifies segmentation with the connections that are based on connective criteria. Just as connections, the segmentations can then
be regrouped by suprema and infima. The generality of the theorem makes it valid for functions from any space to any other
one. Two propositions make precise the AND and OR combinations of connective criteria.
The soundness of the approach is demonstrated by listing a series of segmentation techniques. One considers first the cases
when the segmentation under study does not involve initial seeds. Various modes of regularity are discussed, which all derive
from Lipschitz functions. A second category of examples involves the presence of seeds around which the partition of the space
is organized. An overall proposition shows that these examples are a matter for the central theorem. Watershed and jump connection
based segmentations illustrate this type of situation. The third and last category of examples deals with cases when the segmentation
occurs in an indirect space, such as an histogram, and is then projected back on the actual space under study.
The relationships between filtering and segmentation are then investigated. A theoretical chapter introduces and studies the
two notions of a pulse opening and of a connected operator. The conditions under which a family of pulse openings can yield a connected filter are clarified. The ability of segmentations
to generate pyramids, or hierarchies, is analyzed. A distinction is made between weak hierarchies where the partitions increase
when going up in the pyramid, and the strong hierarchies where the various levels are structured as semi-groups, and particularly
as granulometric semi-groups.
The last section is based on one example, and goes back over the controversy about “lattice” versus “functional” optimization.
The problem is now tackled via a case of colour segmentation, where the saturation serves as a cursor between luminance and
hue. The emphasis is put on the difficulty of grouping the various necessary optimizations into a single one. 相似文献
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5.
介绍了路面管理系统数据采集技术、数据库管理技术、路面使用性能评价及预测模型、养护决策模型在山西省的推广应用情况,并指出了取得的社会经济效益,阐明了其科学性、适用性和可操作性,证明其推广应用的价值。 相似文献
6.
对韶钢炼铁厂4号高炉炉况和操作上存在的问题进行了分析,主要原因是原材料质量较差,精料水平低,同时,高炉操作不能完全适应原材料条件.按照上稳下活工艺的原则,采取合理鼓风动能、活跃炉缸工作状态、稳定热制度、合理中部冷却强度、炉顶小高压操作以及使用上部调节手段等一系列措施,使高炉的炉况顺行得到了较大的改善,各项主要技术经济指标取得相应的进步.2001年利用系数达3.024 t/m3·d,焦比达441 kg/t. 相似文献
7.
This study was to compare theoretical calculation and practical measurement structure response of asphalt pavement. Analysis of the pavement layer moduli was determined from a Back-calculation of Falling Weight Deflectometer (FWD) data and the measured stiffness moduli of asphalt layer cores. The pavement response was calculated using a theoretical model and the measured strain response at the bottom different layers. Layered elastic theory was used to back-calculate the layer moduli and three different theory models were used to forward calculate the strain and deflection. The models were: Layered Elastic Theory (LET), the Method of Equivalent Thicknesses (MET) with linear elastic and the Finite Element Method (FEM) where asphalt layer may be viscoelastic. The results showed that the calculation structure response from FEM was consistent with measured results. 相似文献
8.
供水工程输水隧洞钻爆设计与施工 总被引:1,自引:1,他引:0
介绍了采用钻焊法开挖深圳市东部供水工程输水隧洞的掏槽方式,光面爆破参数,装药结构及钻爆作业安排等参数。在近4年的工程实践中,取得了良好的爆破效果和明显的经济效益。 相似文献
9.
铵油炸药在炮孔爆破中的应用 总被引:1,自引:0,他引:1
文章介绍了在炮孔直径小于100mm条件下,尤其是光面和预裂爆破中,使用铵油炸药的体会及有关施工工艺. 相似文献
10.
The smooth fractionator 总被引:8,自引:0,他引:8
H. J. G. Gundersen 《Journal of microscopy》2002,207(3):191-210
A modification of the general fractionator sampling technique called the smooth fractionator is presented. It may be used in almost every situation in which sampling is performed from distinct items that are uniquely defined, often they are physically separated items or clusters like pieces, blocks, slabs, sections, etc. To each item is associated a ‘guesstimate’ or an associated variable with a more‐or‐less close – and possibly biased ? relationship to the content of the item. The smooth fractionator is systematic sampling among the items arranged according to the guesstimates in a unique, symmetric sequence with one peak and minimal jumps. The smooth fractionator is both very simple to implement and so efficient that it should probably always be used unless the natural sequence of the sampling items is equally smooth. So far, there is no theory for the prediction of the efficiency of smooth fractionator designs in general, and their properties are therefore illustrated with a range of real and simulated examples. At the cost of a slightly more elaborate sampling scheme, it is, however, always possible to obtain an unbiased estimate of the real precision and of some of the variance components. The only real practical problem for always obtaining a high precision with the smooth fractionator is specimen inhomogeneity, but that is detectable at almost no extra cost. With careful designs and for sample sizes of about 10, the sampling variation for the primary, smooth fractionator sampling step may in practice often be small enough to be ignored. 相似文献