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南通市1999—2008年肺癌死亡率变化趋势分析 被引量:8
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作者 尹敏 夏小娟 +1 位作者 庄勋 黄建萍 《中国癌症杂志》 CAS CSCD 北大核心 2011年第2期140-143,共4页
背景与目的:随着社会的发展、生活模式的改变及环境的变化,肺癌越来越严重地威胁到居民的健康。本研究描述并分析南通市1999—2008年肺癌死亡率的变化趋势,旨在为相关部门制定肺癌的预防与控制政策提供科学依据。方法:利用1999—2008年... 背景与目的:随着社会的发展、生活模式的改变及环境的变化,肺癌越来越严重地威胁到居民的健康。本研究描述并分析南通市1999—2008年肺癌死亡率的变化趋势,旨在为相关部门制定肺癌的预防与控制政策提供科学依据。方法:利用1999—2008年南通市居民的死因监测资料,按年龄、性别计算粗死亡率和中调率,利用年度变化百分比(annual percent change,APC)检验分析南通市肺癌近10年流行趋势。结果:1999—2008年南通市居民肺癌平均粗死亡率为39.98/10万,中调率为26.59/10万,世调率为26.39/10万。男性粗死亡率显著高于女性(55.82/10万比24.61/10万,χ2=4 712,P<0.001)。10年间,粗死亡率呈上升趋势,APC为5.57%,中调率上升不明显,APC为1.41%。女性肺癌在恶性肿瘤疾病谱中上升明显,由第4位上升到第1位。老年人(65岁以上)肺癌粗死亡率及中调率均上升,APC分别为2.63%和2.22%。结论:南通市肺癌粗死亡率上升可能是由于人口老龄化造成。肺癌的预防与控制应成为南通市肿瘤防治工作的重要任务。 展开更多
关键词 肺癌 粗死亡 中调率 变化趋势
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Application of Large-Scale Systems Theory in Fire Control Systems
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作者 史天运 何广存 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期21+17-21,共6页
According the to the model of single tank fire control system, this paper makes use of decomposition-coordination theory of large-scale systems to discuss the shooting problem of multiple tank the control systems, and... According the to the model of single tank fire control system, this paper makes use of decomposition-coordination theory of large-scale systems to discuss the shooting problem of multiple tank the control systems, and alalyzes specifically the three-tank the control systems and models.the process was imitated in computer, and the optimal shooting element of 3TS system was got. In addition, probability of hitting the target was calculated. 展开更多
关键词 large-scale systems fire control systems coordination/shooting error probability of hitting the target
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The Analysis of Secure HARQ with Chase Combining over Block Fading Channel 被引量:1
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作者 Yue Wu Lukman A Olawoyin +1 位作者 Nana Zhang Hongwen Yang 《China Communications》 SCIE CSCD 2016年第5期82-88,共7页
In this letter, the physical layer security of hybrid automatic repeat request with chase combining(HARQ-CC) scheme is investigated from the viewpoint of information theory. Different from the literature which used Wy... In this letter, the physical layer security of hybrid automatic repeat request with chase combining(HARQ-CC) scheme is investigated from the viewpoint of information theory. Different from the literature which used Wyner code, our analysis focuses on the general scenario without specific code. We firstly obtain the outage probability of both main channel and wiretap channel. Since retransmissions are completely determined by main channel, we then prove that its achievable diversity order equals to maximum transmission number() while this order of wiretap channel is only one. Furthermore, we evaluate the metric of secure gap which demonstrates the difference between main channel and wiretap channel with reliable and secure constraints. As increases, the secure gap decreases monotonously. When is large enough, the security can be guaranteed even if wiretap channel is better than main channel. 展开更多
关键词 physical layer security HARQ chase combining outage probability diversity order secure gap
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Schedule optimization to improve trunk-local bus transfer efficiency in small conurbations: A case study of New York's capital region
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作者 张大鹏 王晓坤 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1817-1822,共6页
Fostering the use of transit has been broadly accepted as an effective way to improve social equity and reduce the externalities caused by transportation. In the great body of transit literature, many have focused on ... Fostering the use of transit has been broadly accepted as an effective way to improve social equity and reduce the externalities caused by transportation. In the great body of transit literature, many have focused on the improvement of transfer efficiency. However, investigation on transit transfer efficiency is still lacking for medium sized cities or suburban areas that have sprawled from city centers. The special features associated with such an urban form lead to unique travel patterns and bus operations. This work develops a process to improve bus transfer efficiency for small conurbations considering their special characteristics. A case study of New York's Capital District is used to illustrate the proposed method. Results show that the transfer waiting time can be remarkably shortened. The proposed method can be widely adapted to other transit systems in small conurbations. 展开更多
关键词 transfer efficiency small conurbation rural transit
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On nonparametric change point estimator based on empirical characteristic functions 被引量:3
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作者 TAN ChangChun SHI XiaoPing +1 位作者 SUN XiaoYing WU YueHua 《Science China Mathematics》 SCIE CSCD 2016年第12期2463-2484,共22页
We propose a nonparametric change point estimator in the distributions of a sequence of independent observations in terms of the test statistics given by Huˇskov′a and Meintanis(2006) that are based on weighted empi... We propose a nonparametric change point estimator in the distributions of a sequence of independent observations in terms of the test statistics given by Huˇskov′a and Meintanis(2006) that are based on weighted empirical characteristic functions. The weight function ω(t; a) under consideration includes the two weight functions from Huˇskov′a and Meintanis(2006) plus the weight function used by Matteson and James(2014),where a is a tuning parameter. Under the local alternative hypothesis, we establish the consistency, convergence rate, and asymptotic distribution of this change point estimator which is the maxima of a two-side Brownian motion with a drift. Since the performance of the change point estimator depends on a in use, we thus propose an algorithm for choosing an appropriate value of a, denoted by a_s which is also justified. Our simulation study shows that the change point estimate obtained by using a_s has a satisfactory performance. We also apply our method to a real dataset. 展开更多
关键词 change point estimator empirical characteristic function tuning parameter convergence rate asymptotic distribution
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Accuracies of Global Land Cover Maps Checked against Fluxnet Sites 被引量:1
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作者 Peng Gong 《Science Foundation in China》 CAS 2008年第1期31-35,共5页
Global land cover data products are key sources of information in understanding the complex interactions between human activities and global change. They play a critical role in improving performances of ecosystem, hy... Global land cover data products are key sources of information in understanding the complex interactions between human activities and global change. They play a critical role in improving performances of ecosystem, hydrological and atmospheric models. Three freely available global land cover products developed in the United States are popularly used by the scientific community. These include two global maps developed separately by the United States Geological Survey (USGS) and the University of Maryland (UMD) with NOAA Advanced Very High Resolution Radiometer ( AVHRR ) data, and one developed by Boston University with the EOS Moderate Resolution Imaging Spectroradiometer ( MODIS) data. They are compared with known land cover types at 250 available Fluxnet sites around the world. The overall accuracies are 37%, 36% and 42%, respectively for the USGS, UMD and Boston global land cover maps, Some future global land cover mapping strategies are suggested. 展开更多
关键词 global land cover map
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Graphdiyne as a saturable absorber for 2-µm all-solid-state Q-switched laser 被引量:1
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作者 Yuqian Zu Jia Guo +4 位作者 Qianqian Hao Feng Zhang Cong Wang Jie Liu Bing Wang 《Science China Materials》 SCIE EI CSCD 2021年第3期683-690,共8页
As a novel one-atom-thick carbon allotrope,graphdiyne(GDY)has attracted wide interest in two-dimensional materials owing to its unique feature with a planar layer comprising sp2-and sp-hybridized carbon atoms and a di... As a novel one-atom-thick carbon allotrope,graphdiyne(GDY)has attracted wide interest in two-dimensional materials owing to its unique feature with a planar layer comprising sp2-and sp-hybridized carbon atoms and a direct natural bandgap.A high-quality saturable absorber(SA)based on GDY was successfully fabricated,and the nonlinear saturable absorption properties were investigated.A compact diode-pumped solid-state passively Q-switched laser based on the as-prepared GDY-SA could be operated at 2µm.The Q-switched laser delivered a maximum average output power of 1.29 W at a central wavelength of 1908.41 nm with up to 54.8%slope efficiency.A repetition rate of 91.58 kHz and single pulse energy of 23.08µJ were obtained.This work is the first application of GDY as an SA to generate all-solid-state pulsed lasers.These results indicate that GDY is a promising SA for solid-state pulsed lasers and has further application potential for ultrafast photonic devices in the 2-µm region. 展开更多
关键词 graphdiyne saturable absorber all-solid-state laser passively Q-switched two-dimensional materials
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A simplified tunable frequency interval optical frequency comb generator using a single continuous-wave laser
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作者 刘丽 徐铁峰 +2 位作者 戴振祥 戴世勋 刘太君 《Optoelectronics Letters》 EI 2017年第2期104-107,共4页
We propose and demonstrate a simplified and tunable frequency interval optical frequency comb(OFC) generator based on a dual-drive Mach-Zehnder modulator(DD-MZM) using a single continuous-wave(CW) laser and low-power ... We propose and demonstrate a simplified and tunable frequency interval optical frequency comb(OFC) generator based on a dual-drive Mach-Zehnder modulator(DD-MZM) using a single continuous-wave(CW) laser and low-power radio frequency(RF) driven signal. A mathematical model for the scheme is established. The 21-and 29-mode OFCs with frequency interval ranging from 6 GHz to 40 GHz are obtained under DD-MZM driven by a low-power RF signal within a maximum bandwidth of 1.12 THz. The generated OFCs exhibit spectral flatnesses of less than 0.5 d B and 0.8 d B within bandwidths of 160 GHz and 400 GHz, respectively. 展开更多
关键词 tunable simplified generator modulator flatness bandwidth resonator cascade utilize locked
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