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1.
This article presents a report on APNOMS 2008, which was held October 22–24, 2008 in Beijing, China. The theme of APNOMS 2008 was “Challenges for Next Generation Network Operations and Service Management.”  相似文献   

2.
Journal of Network and Systems Management - This article presents a report on APNOMS 2020, which was held on September 22–25, 2020, at EXCO, Daegu, South Korea. The theme of APNOMS 2020 was...  相似文献   

3.
This paper presents a report on APNOMS 2013, which was held September 25–27, 2013 in the International Conference Center, Hiroshima, Japan. The theme of APNOMS 2013 was “Integrated Management of Network Virtualization”.  相似文献   

4.
This article presents a report on APNOMS 2011, which was held September 21–23, 2011 in Taipei, Taiwan. The theme of APNOMS 2011 was “Managing Clouds, Smart Networks and Services.”  相似文献   

5.
This article presents a report on APNOMS 2007, which was held October 10–12, 2007 in Sapporo, Japan. The theme of APNOMS 2007 was “Managing the Next Generation Networks and Services.”
Choong Seon HongEmail:
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6.
VerifyThis 2015     
VerifyThis 2015 was a one-day program verification competition which took place on April 12th, 2015 in London, UK, as part of the European Joint Conferences on Theory and Practice of Software (ETAPS 2015). It was the fourth instalment in the VerifyThis competition series. This article provides an overview of the VerifyThis 2015 event, the challenges that were posed during the competition, and a high-level overview of the solutions to these challenges. It concludes with the results of the competition and some ideas and thoughts for future instalments of VerifyThis.  相似文献   

7.
油井、风机和道路是黄河三角洲区域的主要人工地物,明确其时空特征对保障黄河三角洲的生态安全具有重要意义。利用Landsat、SPOT、高分二号等中、高分辨率卫星影像,提取并建立2000年和2015年黄河三角洲主要人工地物分布数据集,使用核密度法、平均最近邻法、加权分析法、克里金插值法和空间自相关分析法分析2000~2015年黄河三角洲人工地物的时空特征。结果表明:(1) 2015年风机空间分布具有不均衡性,呈现两大核心区为主、3个小集聚区为辅的空间分布格局,总体呈西北—东南走向,空间集聚特征明显;(2) 2000年和2015年油井空间分布具有不均衡性且存在时间变异特征,2000年油井呈现两大核心为主,团块成片分布为辅的空间分布格局,2015年油井呈现三大核心区为主、核心区周围油井呈鞍状分布的空间格局特征;(3) 2000~2015年黄河三角洲路网密度不断提高,空间集聚特征明显,路网密度高值主要分布在黄河三角洲中部地区,并呈现向西部和南部扩散趋势。总的来说,黄河三角洲地区人工地物数量大、分布范围广、增长速度快,对自然保护区的生态安全造成了巨大威胁。通过识别和分析黄河三角洲人工地物及其时空特...  相似文献   

8.
Urban land cover composition is the key factor affecting the living environment and urban ecosystem service. Based on the Google Earth Engine platform, Landsat 5/8 remote sensing image data were used to adopt the improved "Vegetation-Impervious Surface-Soil" model and linear spectral mixed decomposition method. The variation characteristics of land cover in Nur-Sudan, Almaty, Urumqi cities from 1990 to 2015 were compared and analyzed. The results show that the urban built-up area of Urumqi city expanded the largest area of the three cities from1990 to 2015, with an expansion of 349.81 km2, followed by Nur-Sultan, with a city expansion area of 158.16 km2. As the capital of Kazakhstan was relocated from Almaty to Nur-Sultan, the city of Almaty expanded the slowest during the entire period, with a total expansion of 126.23 km2. In the urban built-up area, the urban surface in Urumqi increased by 7.10% from 1990 to 2015, and the Nur-Sultan and Almaty decreased by 14.9% and 4.49%,respectively. The green space component of the built-up area, Nur-Sultan increased by 6.68% from 1990 to 2015, while Urumqi and Almaty decreased by 6.65% and 2.75%,respectively. The different surface cover patterns of cities are different for different reasons. Urumqi is mainly supported by national policies, and Almaty is known for its historical background and urban planning, while the rapid development of Nur-Sudan was affected by the relocation of Kazakhstan.  相似文献   

9.
城市地表覆盖组分是影响人居生存环境和城市生态系统服务的关键因素。基于Google Earth Engine平台,利用Landsat 5/8遥感影像数据,采用改进的“植被—不透水面—土壤”模型及线性光谱混合分解方法,提取地处干旱区的中国西部大城市乌鲁木齐市与邻国哈萨克斯坦首都城市努尔–苏丹市、大城市阿拉木图市的地表覆盖信息,对比分析1990~2015年3个城市地表覆盖的变化特征。结果表明:1990~2015年间乌鲁木齐市城市建成区扩张面积最大,扩张了349.81 km2;其次为努尔-苏丹市,城市扩张面积为158.16 km2;由于哈萨克斯坦首都由阿拉木图市迁往努尔-苏丹市,整个时段阿拉木图市城市扩张最慢,总计扩张了126.23 km2。在城市建成区内,1990年到2015年间乌鲁木齐市城市地表不透水组分增加了7.10%,努尔—苏丹市和阿拉木图市分别减少了14.9%、4.49%。建成区内绿地组分努尔—苏丹市从1990年到2015年增加了6.68%;乌鲁木齐市和阿拉木图市分别减少了6.65%和2.75%。城市所表现出来的不同地表覆盖特征乌鲁木齐市主要受国家政策支持,阿拉木图市由于其历史背景和城市规划,努尔—苏丹市城市的快速发展则受哈萨克斯坦迁都的影响。  相似文献   

10.
Old satellite sensors lack several quality features such as high spatial and spectral resolution. For accurate long-term change detection, improvement of the quality of old satellite images is required. In the present study, we used two wavelet-based image enhancement techniques [(discrete wavelet transform (DWT) and dual tree-complex wavelet transform (DT-CWT)] for improving the quality of Landsat 2 data of 1975 and Landsat 8 data of 2015 to study the impact of coal mining on land use change over a period of four decades. The enhanced images were subjected to land-use classification using Support Vector Machines. Land-use classification accuracy was measured using confusion matrix-based accuracy assessment. Accuracy assessment revealed that the overall classification accuracy of DWT enhanced images was 82.10% for the year 1975 and 88.46% for the year 2015. The overall classification accuracy of DT-CWT enhanced images was 85.71% for the year 1975 and 88.54% for the year 2015. The results of change detection revealed that the total areal coverage of dense vegetation increased by 65%, indicating that the rate of land degradation had slowed down due to the legislative and policy changes to promote sustainable development in coal mining after 1986.  相似文献   

11.
In this work we study the parallel coordinate descent method (PCDM) proposed by Richtárik and Taká? [Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52] for minimizing a regularized convex function. We adopt elements from the work of Lu and Xiao [On the complexity analysis of randomized block-coordinate descent methods, Math. Program. Ser. A 152(1–2) (2015), pp. 615–642], and combine them with several new insights, to obtain sharper iteration complexity results for PCDM than those presented in [Richtárik and Taká?, Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52]. Moreover, we show that PCDM is monotonic in expectation, which was not confirmed in [Richtárik and Taká?, Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52], and we also derive the first high probability iteration complexity result where the initial levelset is unbounded.  相似文献   

12.
基于OMI对流层NO2柱浓度产品研究了2005~2015年中国及各省(市、区)NO2时空变化及影响因素:①中国对流层NO2柱浓度2005~2009年波动较小,2010~2011年升幅较大,2012年较2011年有所下降,2013年与2012年持平,2014、2015年持续大幅下降;②中国NO2高浓度分布面积11年来变化显著,五级高浓度分布面积2005~2011年呈显著上升趋势,2011年面积最大为37.2万km2;2011~2013年波动较小;2014~2015年呈直线下降趋势,2015年降低到6.1万km2;③上海、天津两市对流层NO2柱浓度处于五级高浓度水平,其中上海是中国浓度最高的城市,山东是中国浓度最高的省;④对流层NO2柱浓度的变化与第二产业生产总值相关性很大,需要调整优化产业结构降低第二产业比重才能得到改善;长期依赖燃煤高污染的能源结构也是导致NO2浓度居高不下的一个重要原因,亟需开发新能源以替代煤燃料等各种办法;机动车保有量快速增加,汽车标准及油品跟不上国际发展水平,导致NO2排放量大增。  相似文献   

13.
The absorbed and utilized Fraction of Photosynthetically Active Radiation(FPAR) reflects the capacity of carbon fixation and oxygen release by vegetation, which may vary over space and time in large scale. Analysis of spatial-temporal variation in FPAR is an important topic of plant ecology. Based on GIMMS NDVI3g (1982~2015) and MODIS NDVI (2001~2015) data in the Tibetan plateau, here we used the nonlinear, semi-theoretical and semi-empirical models to inverse and analyze the spatial and temporal variation in FPAR. The results showed that (1) The spatial distributions of FPAR derived from GIMMS NDVI3g and MODIS NDVI were highly consistent, with the correlation coefficient being 0.82 (P<0.01). The area in which the trends of inter-annual change in the two inversion data were consistent for at least 6 years made up 80% of the studying area. (2) FPAR in Tibetan Plateau was greatly affected by slope and altitude. Changes in FPAR were fastest at slopes of 15~35 degrees and highest at altitude of 700~2 100 m. The effect of slope direction on FPAR was limited. There was little difference in FPAR among different slope directions except for the south where the FPAR was relatively lower. (3)The FPAR data from 1982 to 2015 demonstrated seasonal variation. The inter-annual variation in FPAR was most significant in winter, in which FPAR in about 78.5% of the area increased. FPAR declined most significantly in the fall. (4) FPAR derived from both the MODIS NDVI and GIMMS NDVI data demonstrated a small, temporary decline in 2012. The trend of inter-annual variation in FPAR was largely different among different vegetation types. In conclusion, the FPAR data from 1982 to 2015 in the Tibetan plateau demonstrated both spatial and seasonal variation, which may have important implications for further studies concerning climate and environmental changes in the region.  相似文献   

14.
This paper is devoted to stability analysis of continuous-time delay systems based on a set of Lyapunov–Krasovskii functionals. New multiple integral inequalities are derived that involve the famous Jensen’s and Wirtinger’s inequalities, as well as the recently presented Bessel–Legendre inequalities of Seuret and Gouaisbaut (2015) and the Wirtinger-based multiple-integral inequalities of Park et al. (2015) and Lee et al. (2015). The present paper aims at showing that the proposed set of sufficient stability conditions can be arranged into a bidirectional hierarchy of LMIs establishing a rigorous theoretical basis for comparison of conservatism of the investigated methods. Numerical examples illustrate the efficiency of the method.  相似文献   

15.
International Journal of Control, Automation and Systems - A precise train navigation system for Korean high-speed trains having a maximum speed of 400km/h or higher was developed in 2015. The...  相似文献   

16.
海岸带湿地具有重要的生态价值和经济开发价值,明确其时空变化特征与影响因素对于维持区域生态系统平衡和可持续发展具有重要意义。以Landsat TM/ETM+/OLI影像为基本数据源,综合利用面向对象与深度学习分类方法对1985~2015年闽东南低海拔海岸带地区的湿地信息进行提取,以揭示其时空演变特征与驱动力因素。结果表明:基于面向对象—深度学习分类方法对湿地进行信息提取,整体分类精度可达93%以上,分类结果整体性好;1985~2015年自然湿地面积呈减少趋势,人工湿地面积呈增加趋势,分别减少和增加250.31 km2和251.36 km2;湿地二级类型中,30 a间河口/浅海水域和淤泥质海滩面积减少最大,盐田/水产养殖场面积增加最大;1985~2015年湿地变化类型多样,且2000~2015年较1985~2000年湿地变化更为剧烈;湿地变化是人类活动和自然环境变化共同作用的结果,其中人类活动是影响湿地变化的主要原因。该方法及研究结果可为海岸带湿地监测与保护管理提供技术支持和决策参考。  相似文献   

17.
在“一带一路”倡议框架下,中缅经济走廊逐步从概念转入实质规划建设阶段,了解和掌握缅甸土地覆被的空间格局和分布特征对于合理开发利用资源、制定务实的经济廊道建设规划具有重要的战略意义。利用Landsat-8 OLI遥感影像数据,基于多分类器集成的面向对象迭代分类方法(OIC-MCE),生产了缅甸2015年30 m分辨率土地覆被产品(MyanmarLC-2015)。采用Google Earth高分辨率影像获取验证样本用于产品精度验证,验证结果表明:MyanmarLC-2015产品的总体分类精度为89.05%,Kappa系数为0.87,各类别的用户精度和制图精度均超过72%,能够准确地反映缅甸土地覆被类型的空间格局。根据产品统计,林地是缅甸面积最大的土地覆被类型,占国土面积56.15%,以常绿阔叶林为主,占林地面积83.57%。耕地面积次之,占国土面积27.01%。地形因子对缅甸土地覆被类型空间分布格局有显著的影响,随着海拔升高,呈现出按如下顺序的垂直地带性特征:森林湿地、水田、旱地、落叶灌木林、落叶阔叶林、常绿灌木林、常绿阔叶林、常绿针叶林。从植被生产力的角度来看,缅甸东部、东北部和东南部植...  相似文献   

18.
With the development of urbanization in China, construction land (CL) expansion is obvious, and urban heat island (UHI) is becoming more and more serious. Many scholars have shown a strong interest in the study of UHI caused by land expansion, but less attention has been paid to the coupling relationship between CL expansion and high-temperature area (HTA) expansion during the process of urbanization. This study obtained the land surface temperature (LST) data of China’s three major urban agglomerations (CTM-UAs) in 2000, 2005, 2010 and 2015. Then this paper used overall coupling model and spatial coupling model to reveal the coupling relationship between the CL expansion and HTA expansion of CTM-UAs in different periods. The results showed that: (1) From 2000 to 2015, the trend of CL expansion and HTA expansion in CTM-UAs was synchronous; (2) The distance between the CL barycentre and HTA barycentre in CTM-UAs was shrinking, the spatial overlap was constantly strengthening, and the overall coupling was constantly strengthening. And the highest value of the overall coupling was reached in 2015; (3) The number of grid units of very strong coupling and strong coupling increased with fluctuation in Beijing-Tianjin-Tangshan Urban Agglomeration (BTT), that in Yangtze River Delta Urban Agglomeration (YRD) was increasing, and that of Guangdong-Hong Kong-Macao Urban Agglomeration (GHM) has gone through the process of increasing to decrease.  相似文献   

19.
针对传统的身份基全同态加密(IBFHE)方案无法对不同身份标识(ID)下的密文进行同态运算的问题,提出一个基于误差学习(LWE)问题的分层身份基多用户全同态加密方案。该方案利用Clear等(CLEAR M,McGOLDRICK C.Multi-identity and multi-key leveled FHE from learning with errors.Proceedings of the 2015 Annual Cryptology Conference,LNCS 9216.Berlin:Springer,2015:630-656)在2015年提出的身份基多用户全同态加密方案([CM15]方案)的转化机制,结合Cash等(CASH D,HOFHEINZ D,KILTZ E,et al.Bonsai trees,or how to delegate a lattice basis.Proceedings of the 2010 Annual International Conference on the Theory and Applications of Cryptographic Techniques,LNCS 6110.Berlin:Springer,2010:523-552)在2010年提出的身份基加密(IBE)方案([CHKP10]方案),实现了不同身份标识下的密文同态运算,应用前景更加广阔,在随机预言机模型下为基于身份匿名的选择明文攻击下的不可区分性(IND-ID-CPA)安全。与[CM15]方案相比,该方案在公钥规模、私钥规模、密文尺寸、分层性质和密钥更新周期方面都具有优势。  相似文献   

20.
The severe summer ozone(O3) pollution in North China has attracted much attention.Combined summerO3 monitoring and NDVI data for 2015-2016,we firstly assessed the impact ofO3pollution on vegetation growth activities.Developed a simple linear simulation technique,then we detected and evaluatedO3’s impact on summer vegetation growth.The results show that summerO3pollution is closely related to vegetation growth in North China.In spatial-scale the stronger affected regions by O3,whereas associated with a highO3pollution intensity,and vice versa.In sum,summerO3 pollution affected on the vegetation growth activities in North China.In addition,in time\|scale,the impact of 2016 is very different from that of 2015.In 2016,a higher O3 pollution intensity than that of 2015,but a decrease in the impact with an approximately 2.75 %.In addition,O3pollution\|induced changes in vegetation growth activities during 2015-2016 were about 11.7 %.This study provides a method for remote sensing to monitor the effects ofO3pollution on terrestrial ecosystems.  相似文献   

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