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81.
During the 1990s, the township of Pōkeno was held up as an example of a declining rural Aotearoa/New Zealand. By‐passed from the national state highway, it lost its status as a service hub and drastic measures were introduced to revitalise the town, including renaming the town “ Jenniferann.com .” Pōkeno has since undergone an unlikely transformation, with foreign investment and its location within an extended Auckland commuter zone meaning that the township has grown exponentially. This article describes the transformation of Pōkeno and uncovers what has been missing from discussions about Pōkeno's reinvention, namely, the place of mana whenua.  相似文献   
82.
83.
This paper introduces a unique industrial configuration that has emerged in Beijing, where three economic clusters in the biomedical industry, originally established as industrial/research parks, have developed parallel to each other. This configuration of multiple co-located clusters of the same industry, which has not been discussed before, raises the question of whether the industrial/research parks are competing for the same resources, or whether they are complementary to each other and can collectively be viewed as a new type of industrial configuration. The paper conceptualizes a framework of multiple clusters in mega-city regions that distinguishes between collaborating and competing clusters and presents initial empirical evidence for the Beijing case. As such, this research aims to unravel the phenomenon of multiple clusters in mega-city regions and to understand the complex spatial interrelationships that exist within and beyond multiple co-located clusters in the same industry.  相似文献   
84.
New palaeotemperature reconstructions have been obtained on the basis of oxygen isotopic analysis of 178 aragonitic shell samples taken from specimens of three ammonoid orders (and some corresponding families): Phylloceratida (Phylloceratidae), Lytoceratida (Tetragonitidae) and Ammonitida (Oppeliidae, Desmoceratidae, Silesitidae, Cleoniceratidae and Douvilleiceratidae). Those obtained from aragonite shells, secreted in the lower epipelagic and in the middle mesopelagic zones during coolest season (winter), range from 15.4 to 16.8 °C, and from 11.8 to 12.0 °C, respectively. Presumed spring/autumn palaeotemperatures obtained from aragonite shells, secreted apparently in the upper and lower epipelagic, upper and middle mesopelagic zones, are somewhat higher. Presumed summer palaeotemperatures, calculated apparently for the upper and lower epipelagic, and upper mesopelagic zones range from 19.4 to 21.7 °C, from 17.7 to 19.4 °C, and from 14.4 to 16.1 °C, respectively. The predominant part of investigated ammonoids from Madagascar inhabited the epipelagic zone, but some phylloceratid, tetragonitid and silesitid ammonoids preferred deeper, cooler conditions (upper-middle mesopelagic zone). The study supports the hypothesis that Madagascar was located in middle latitudes within the tropical-subtropical climatic zone during the early Albian. Available carbon and strontium isotope data allow us to assume a more or less expressed carbon and strontium isotope stratification of the water column in this region in the early Albian. On the basis of the stable isotope data, following partly Lukeneder (2015), two large ethological groups can be recognised mainly in mid-aged and adult ammonoids. Some ammonoids (group 1) preferred apparently mesopelagic conditions, and to a lesser degree the epipelagic zone, being mainly cool-requiring animals. However, a significant part of the isotopically investigated ammonoids (group 2) preferred, on the contrary, only epipelagic conditions, being mainly thermophilic dwellers.  相似文献   
85.
Grid pattern recognition in road networks using the C4.5 algorithm   总被引:1,自引:0,他引:1  
Pattern recognition in road networks can be used for different applications, including spatiotemporal data mining, automated map generalization, data matching of different levels of detail, and other important research topics. Grid patterns are a common pattern type. This paper proposes and implements a method for grid pattern recognition based on the idea of mesh classification through a supervised learning process. To train the classifier, training datasets are selected from worldwide city samples with different cultural, historical, and geographical environments. Meshes are subsequently labeled as composing or noncomposing grids by participants in an experiment, and the mesh measures are defined while accounting for the mesh’s individual characteristics and spatial context. The classifier is generated using the C4.5 algorithm. The accuracy of the classifier is evaluated using Kappa statistics and the overall rate of correctness. The average Kappa value is approximately 0.74, which corresponds to a total accuracy of 87.5%. Additionally, the rationality of the classifier is evaluated in an interpretation step. Two other existing grid pattern recognition methods were also tested on the datasets, and comparison results indicate that our approach is effective in identifying grid patterns in road networks.  相似文献   
86.
对青蛤(Cyclina sinensis)转录组文库筛选并克隆得到青蛤TRAF6(Cs TRAF6)基因的c DNA序列,其开放阅读框为2337bp,编码778个氨基酸,分子量为86.59k Da。Cs TRAF6蛋白包含RING型锌指结构,两个TRAF型锌指结构,coiled-coil结构域以及MATH结构域。经生物信息学及分子系统学分析表明Cs TRAF6属于TRAF6家族的一员。利用实时荧光定量PCR方法检测了Cs TRAF6基因在青蛤各个组织以及在Poly I:C侵染下在血淋巴中的时序性表达情况。结果表明,Cs TRAF6基因在青蛤血淋巴、闭壳肌、鳃、性腺、外套膜和肝脏中普遍表达,其中在血淋巴中的表达水平最高。在Poly I:C刺激后的3h,青蛤血淋巴中Cs TRAF6的表达量迅速升高,在6h达到最大值,说明青蛤的Cs TRAF6基因参与了病毒类似物侵染下的免疫应答反应。  相似文献   
87.
针对岩石颗粒边缘模糊、结构复杂的特点,为了更有效地识别颗粒边缘,在基于特征值的C3相干算法的基础上,融合多尺度和多角度的特征表达,提出了一种改进的C3相干算法。该算法综合考虑岩石薄片图像角度域光学特征、空间尺度信息和各向异性信息,能更有效地表征颗粒边缘特征,表现出对复杂矿物结构的适应能力。在采集的岩石薄片正交偏光图像上验证提出的算法,实验结果表明,与原生C3相干算法相比,改进后的C3相干算法在全局图像上的方差和灰度差分乘积分别提升了68.41%和22.91%,信息熵下降了21.61%。  相似文献   
88.
Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments,but most studies use GIS-based classification methods to conduct susceptibility zonation.This study presents a machine learning approach based on the C5.0 decision tree(DT)model and the K-means cluster algorithm to produce a regional landslide susceptibility map.Yanchang County,a typical landslide-prone area located in northwestern China,was taken as the area of interest to introduce the proposed application procedure.A landslide inventory containing 82 landslides was prepared and subse-quently randomly partitioned into two subsets:training data(70%landslide pixels)and validation data(30%landslide pixels).Fourteen landslide influencing factors were considered in the input dataset and were used to calculate the landslide occurrence probability based on the C5.0 decision tree model.Susceptibility zonation was implemented according to the cut-off values calculated by the K-means clus-ter algorithm.The validation results of the model performance analysis showed that the AUC(area under the receiver operating characteristic(ROC)curve)of the proposed model was the highest,reaching 0.88,compared with traditional models(support vector machine(SVM)=0.85,Bayesian network(BN)=0.81,frequency ratio(FR)=0.75,weight of evidence(WOE)=0.76).The landslide frequency ratio and fre-quency density of the high susceptibility zones were 6.76/km2 and 0.88/km2,respectively,which were much higher than those of the low susceptibility zones.The top 20%interval of landslide occurrence probability contained 89%of the historical landslides but only accounted for 10.3%of the total area.Our results indicate that the distribution of high susceptibility zones was more focused without contain-ing more"stable"pixels.Therefore,the obtained susceptibility map is suitable for application to landslide risk management practices.  相似文献   
89.
The Powder River Basin (PRB) of Wyoming and Montana contains significant coal and coal bed natural gas (CBNG) resources. CBNG extraction requires the production of large volumes of water, much of which is discharged into existing drainages. Compared to surface waters, the CBNG produced water is high in sodium relative to calcium and magnesium, elevating the sodium adsorption ratio (SAR). To mitigate the possible impact this produced water may have on the quality of surface water used for irrigation, the State of Montana passed water anti‐degradation legislation, which could affect CBNG production in Wyoming. In this study, we sought to determine the proportion of CBNG produced water discharged to tributaries that reaches the Powder River by implementing a four end‐member mixing model within a Bayesian statistical framework. The model accounts for the 87Sr/86Sr, δ13CDIC, [Sr] and [DIC] of CBNG produced water and surface water interacting with the three primary lithologies exposed in the PRB. The model estimates the relative contribution of the end members to the river water, while incorporating uncertainty associated with measurement and process error. Model results confirm that both of the tributaries associated with high CBNG activity are mostly composed of CBNG produced water (70–100%). The model indicates that up to 50% of the Powder River is composed of CBNG produced water downstream from the CBNG tributaries, decreasing with distance by dilution from non‐CBNG impacted tributaries from the point sources to ~10–20% at the Montana border. This amount of CBNG produced water does not significantly affect the SAR or electrical conductivity of the Powder River in Montana. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
90.
变差函数的研究在地质统计学中具有十分重要作用,本文运用界面图形图像处理强的C ̄(++)语言实现了界面友好汉化人机对话变差函数的拟合,主要包括管理菜单的生成,实验变差值的求解,变差图的图形显示,标准函数模型的计算及变差函数人机对话求解等部分。最后对比一下回归分析与人机对话拟合结果。  相似文献   
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