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下浒海滨岩相潮间带藤壶类生态的研究
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作者 李进寿 郭团玉 《宁德师专学报(自然科学版)》 2005年第4期350-352,共3页
下浒海滨潮间带藤壶种类经鉴定共有白脊藤壶、白条地藤壶、绿鳞笠藤壶、日本笠藤壶与网纹藤壶等5种,分布从中潮区上层延伸到低潮区.藤壶类是岩相潮间带的优势群落,也是岩相潮间带动物的先驱种群;以密集群聚方式固着生活,这种生活方式与... 下浒海滨潮间带藤壶种类经鉴定共有白脊藤壶、白条地藤壶、绿鳞笠藤壶、日本笠藤壶与网纹藤壶等5种,分布从中潮区上层延伸到低潮区.藤壶类是岩相潮间带的优势群落,也是岩相潮间带动物的先驱种群;以密集群聚方式固着生活,这种生活方式与其生殖、觅食相关;垂直分布特征与各潮区生态条件密切相关,迎浪面是主要的固着面. 展开更多
关键词 下浒 问带 藤壶 硬相底质
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吐哈盆地十红滩矿区层间氧化带特征及找矿方向研究 被引量:3
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作者 李保侠 蒲仁海 魏国祥 《地质找矿论丛》 CAS CSCD 2005年第2期127-131,共5页
文章阐述了十红滩矿区西山窑组沉积、砂体特征和西山窑组层间氧化带纵横展布规模、规律及层间氧化带前锋与铀矿化的关系,尤其对西山窑组第二岩性段、层间氧化带进行了研究和对比,分析了氧化带形成的地质背景;总结了十红滩铀矿床各矿带... 文章阐述了十红滩矿区西山窑组沉积、砂体特征和西山窑组层间氧化带纵横展布规模、规律及层间氧化带前锋与铀矿化的关系,尤其对西山窑组第二岩性段、层间氧化带进行了研究和对比,分析了氧化带形成的地质背景;总结了十红滩铀矿床各矿带的空间展布、矿体形态、规模、铀矿化特点;认为在该矿区西山窑组第一、第二、第四岩性段中有望找到新的铀矿床。 展开更多
关键词 十红滩矿区 氧化 铀矿找矿方向 吐哈盆地 新疆
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银盘水电站左坝肩边坡及坝基岩体加固 被引量:1
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作者 丁秀丽 朱大勇 +2 位作者 张练 杜俊慧 胡进华 《人民长江》 北大核心 2008年第4期28-30,36,共4页
银盘水电站左岸坝肩边坡岩体内存在着多条与边坡斜交的层间剪切带,由于其出露位置与大坝的相对关系,有可能与岩层中发育的其它结构面组合,构成潜在不稳定滑体;边坡开挖后坝轴线上游剪切带上盘岩体较为单薄,且分布有性状较差的大湾组页岩... 银盘水电站左岸坝肩边坡岩体内存在着多条与边坡斜交的层间剪切带,由于其出露位置与大坝的相对关系,有可能与岩层中发育的其它结构面组合,构成潜在不稳定滑体;边坡开挖后坝轴线上游剪切带上盘岩体较为单薄,且分布有性状较差的大湾组页岩,对大坝坝肩及坝基的抗滑稳定均产生不利影响。采用三维刚体极限平衡分析及数值分析方法对银盘水电站左岸坝肩边坡及坝基岩体在施工期、大坝运行期各种水位工况下的变形与稳定性开展了研究;并对边坡的加固效果进行了分析和评价,为边坡及坝基的加固处理设计提供依据。 展开更多
关键词 坝肩边坡 坝基 施工开挖 大坝蓄水 剪切 加固措施 抗滑稳定性 银盘水电站
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江西铅山下湖铅(锌、银)矿床地质特征及成因初探 被引量:3
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作者 罗平 魏英文 李伯春 《福建地质》 2004年第3期111-118,共8页
下湖铅 (锌、银 )矿区位于武夷山隆起北侧饶南坳陷的黄岗山隆断束与永平—广丰坳断束的接触地带的下湖断陷盆地内。矿体产于侏罗系下统水北组层间破碎带内 ,呈层状、似层状 ,产状平缓、倾角为 9°~ 1 3°,与地层产状基本一致... 下湖铅 (锌、银 )矿区位于武夷山隆起北侧饶南坳陷的黄岗山隆断束与永平—广丰坳断束的接触地带的下湖断陷盆地内。矿体产于侏罗系下统水北组层间破碎带内 ,呈层状、似层状 ,产状平缓、倾角为 9°~ 1 3°,与地层产状基本一致。矿体平均品位 :铅 2 .86%、锌 0 .73%、银60 .8%。主要金属矿物为方铅矿、闪锌矿、黄铜矿等。矿石构造以块状为主 ,次为细脉状、网脉状。矿床成因类型属层控 -叠改型铅 (锌、银 ) 展开更多
关键词 铅矿 矿床地质 破碎 深变质岩
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中国大妈的丝巾旋风
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作者 李继勇 《中国测绘》 2019年第8期72-74,共3页
你大爷还是不是你大爷,难以确定,可你大妈已不是多年前的你大妈了,这毫无疑问. “将广场舞跳遍世界的努力遭诟病后,大妈改用七彩丝巾舞动世界了.”一到茶卡盐湖,这感觉愈发强烈.夏日的茶卡,成了露天丝巾博览会,丝巾旗帜般招展,乱花迷眼... 你大爷还是不是你大爷,难以确定,可你大妈已不是多年前的你大妈了,这毫无疑问. “将广场舞跳遍世界的努力遭诟病后,大妈改用七彩丝巾舞动世界了.”一到茶卡盐湖,这感觉愈发强烈.夏日的茶卡,成了露天丝巾博览会,丝巾旗帜般招展,乱花迷眼.遇大妈,甭问带没带,而该问带了多少条丝巾? 展开更多
关键词 旗帜 大妈 世界 大爷 问带 茶卡盐湖 丝巾
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乌江银盘水电站坝址工程地质评价 被引量:3
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作者 甘三才 《人民长江》 北大核心 2008年第4期14-17,共4页
乌江银盘水电站坝址为斜向谷。以碎屑岩层为主,夹碳酸盐岩,岩层倾向右岸偏下游,多种结构面不利组合,存在坝基抗滑稳定、坝肩高边坡开挖稳定等主要工程地质问题。结合坝址工程地质条件,采用平面滑动极限平衡法、赤平投影法和块体理论、... 乌江银盘水电站坝址为斜向谷。以碎屑岩层为主,夹碳酸盐岩,岩层倾向右岸偏下游,多种结构面不利组合,存在坝基抗滑稳定、坝肩高边坡开挖稳定等主要工程地质问题。结合坝址工程地质条件,采用平面滑动极限平衡法、赤平投影法和块体理论、离散元等数值方法对主要工程地质问题进行了分析评价,提出了工程处理建议,结论与初步开挖揭露的地质情况基本一致。 展开更多
关键词 结构面组合 剪切 抗滑稳定 高边坡稳定 银盘水电站
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Rolling horizon scheduling algorithm for dynamic vehicle scheduling system 被引量:1
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作者 贾永基 谷寒雨 席裕庚 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期92-96,共5页
Dynamic exclusive pickup and delivery problem with time windows (DE-PDPTW), aspecial dynamic vehicle scheduling problem, is proposed. Its mathematical description is given andits static properties are analyzed, and th... Dynamic exclusive pickup and delivery problem with time windows (DE-PDPTW), aspecial dynamic vehicle scheduling problem, is proposed. Its mathematical description is given andits static properties are analyzed, and then the problem is simplified asthe asymmetrical travelingsalesman problem with time windows. The rolling horizon scheduling algorithm (RHSA) to solve thisdynamic problem is proposed. By the rolling of time horizon, the RHSA can adapt to the problem'sdynamic change and reduce the computation time by dealing with only part of the customers in eachrolling time horizon. Then, its three factors, the current customer window, the scheduling of thecurrent customer window and the rolling strategy, are analyzed. The test results demonstrate theeffectiveness of the RHSA to solve the dynamic vehicle scheduling problem. 展开更多
关键词 dynamic vehicle scheduling rolling horizon scheduling algorithm EXCLUSIVE pickup and delivery problem with time windows (PDPTW)
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Dimension-down iterative algorithm for the mixed transportation network design problem
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作者 陈群 姚加林 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期236-239,共4页
An optimal dimension-down iterative algorithm (DDIA) is proposed for solving a mixed (continuous/ discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programmin... An optimal dimension-down iterative algorithm (DDIA) is proposed for solving a mixed (continuous/ discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programming with equilibrium constraints (MPEC). The upper level of the MNDP aims to optimize the network performance via both the expansion of existing links and the addition of new candidate links, whereas the lower level is a traditional Wardrop user equilibrium (UE) model. The idea of the proposed DDIA is to reduce the dimensions of the problem. A group of variables (discrete/continuous) are fixed to altemately optimize another group of variables (continuous/discrete). Some continuous network design problems (CNDPs) and discrete network design problems (DNDPs) are solved repeatedly until the optimal solution is obtained. A numerical example is given to demonstrate the efficiency of the proposed algorithm. 展开更多
关键词 mixed network design problem (MNDP) dimension-down iterative algorithm (DDIA) mathematical programming with equilibrium constraint (MPEC)
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湖南城步县金水铜矿地质特征及成因探讨 被引量:4
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作者 谢新泉 张衡龙 《华南地质与矿产》 CAS 2005年第1期37-40,共4页
金水铜矿床受构造控制,热液成矿标志明显。依据成矿地质背景及矿床地质特征、硫同位素和流体包裹体特征等研究认为,成矿物质来源深部,成矿作用具多阶段,成矿流体具热卤水性质;矿床初步确定为岩浆期后热液脉型铜矿床。
关键词 铜矿床 破碎 岩浆热液 湖南城步
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A novel wireless personal area network technology: ultra wide band technology
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作者 GAO Wei-hua GUO Li-li LIANG Zhi-guo 《Journal of Marine Science and Application》 2006年第3期63-69,共7页
Ultra Wideband (UWB) technology is promising for wireless personal area network (WPAN) applications due to its high data rate, low power requirement and short-range characteristics. Instead of exploring new unused fre... Ultra Wideband (UWB) technology is promising for wireless personal area network (WPAN) applications due to its high data rate, low power requirement and short-range characteristics. Instead of exploring new unused frequency band, the UWB communication follows the overlay principle, i.e., sharing the spectrum with existing systems and devices. This novel radio technology has been recently approved by the regulatory authorities in the United States and Canada, and is being considered for approval in Europe and Asia. In this paper, an overview of the UWB radio technology from the technical, economical, and regulatory perspectives is provided. Firstly, the definition of UWB by the Federal Communications Commission (FCC) is introduced, followed by a brief introduction to the history. The current status of the standardization process resulting from the FCC’s recent decision to permit unlicensed operation in the [3.1 - 10.6] GHz band is discussed. Then, the reasons of considering UWB as a future solution for WLAN/WPAN applications are studied. In particular, the unique properties of UWB and its difference from other wireless technology alternatives are studied. Then, the benefits and challenges related to the commercial deployment of UWB for future applications are discussed. Finally, the research problems and challenges posed by the UWB technology are focused. 展开更多
关键词 UWB WLAN high data rate ROBUSTNESS STANDARD multiple access
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咸阳市秦都区双照镇毛村经济发展调研
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作者 刘嫣 《陕西农业科学》 2009年第5期179-180,共2页
陕西省咸阳市秦都区区委区政府组织在全区开展"三带三问三帮"调研活动,我站对秦都区双照镇毛村的农户2008年年收入情况;外出务工人员情况和农户急需解决的困难和问题进行了调研,并提出了具体的意见和建议。
关键词 “三三帮” 毛村 困难 建议
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布尔津盆地西部凹陷铀成矿水文地球化学条件初探
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作者 陈贤春 成海 《华南铀矿地质》 2001年第1期43-49,共7页
根据水成铀矿床理论,本文在论述布尔津盆地水动力及水化学特征的基础上,通过资料综合整理,着重分析西部凹陷第三系层间水的铀水迁移分带规律,对层间氧化带砂岩型铀矿成矿水文地球化学条件进行初步探讨。
关键词 布尔津盆地西部 氧化 水文地球化学 铀成矿
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广西武鸣县南部盖层中的滑脱构造
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作者 黎新 梁承春 刘国献 《南方国土资源》 2004年第2期23-24,共2页
文章初步讨论了广西武鸣南部上古生界盖层中滑脱构造的基本特征、形成方式和时代,认为其可能是华力西末期至印支早期地壳水平拉伸作用的产物。
关键词 广西 武鸣县 滑脱构造 滑动 拖褶皱 层系 面理 线理 泥盆-石炭系盖层
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就计算机课程中Photoshop教学的感悟
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作者 石梅 《神州》 2012年第23期98-98,共1页
在计算机教学中Photoshop是一门操作性和实践性很强的课程。笔者根据近年的实际教学,并针对学生在学习本课程中遇到的问题,主要从学生的实际情况及如何培养学生问题意识、开拓学生思维和提高学生创新能力等谈一下心得体会,为实现Photos... 在计算机教学中Photoshop是一门操作性和实践性很强的课程。笔者根据近年的实际教学,并针对学生在学习本课程中遇到的问题,主要从学生的实际情况及如何培养学生问题意识、开拓学生思维和提高学生创新能力等谈一下心得体会,为实现Photoshop课堂教学的优化和教学效益的提高提些建议。 展开更多
关键词 计算机教学 PHOTOSHOP 学习 项目教学法
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Time-dependent response of laminated isotropic strips with viscoelastic interfaces 被引量:3
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作者 严蔚 陈伟球 《Journal of Zhejiang University Science》 EI CSCD 2004年第11期1318-1321,共4页
The two dimensional problem of simply supported laminated isotropic strips with viscoelastic interfaces and under static loading was studied. Exact solution was derived based on the exact elasticity equation and the K... The two dimensional problem of simply supported laminated isotropic strips with viscoelastic interfaces and under static loading was studied. Exact solution was derived based on the exact elasticity equation and the Kelvin-Voigt viscoelastic interfacial model. Numerical computations were performed for a strip consisting of three layers of equal thickness. Results indicated that the response of the laminate was very sensitive to the presence of viscoelastic interfaces. 展开更多
关键词 Viscoelastic interfaces Isotropic laminated strips Exact solution
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Direction of Arrivals Estimation for Correlated Broadband Radio Signals by MVDR Algorithm Using Wavelet 被引量:3
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作者 Ying Liu Chi Xie Yourun Zhang 《China Communications》 SCIE CSCD 2017年第3期190-197,共8页
A theoretical relationship between the wavelet transform and the fast fourier transformation(FFT) methods in broadband wireless signal is proposed for solving the direction of arrivals(DOAs) estimation problem. This l... A theoretical relationship between the wavelet transform and the fast fourier transformation(FFT) methods in broadband wireless signal is proposed for solving the direction of arrivals(DOAs) estimation problem. This leads naturally to the derivation of minimum variance distortionless response(MVDR) algorithm, which combines the benefits of subspace methods with those of wavelet, and spatially smoothed versions are utilized which exhibits good performance against correlated signals. We test the method's performance by simulating and comparing the performance of proposed algorithm, FFT MVDR and MVDR with correlated signals, and an improved performance is obtained. 展开更多
关键词 array antenna broadband radio signal direction of arrival MVDR algorithm wavelet
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Time-Frequency Bandwidth Product Estimation of Sinusoidal Non-Linear Chirp Keying Scheme 被引量:1
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作者 Zhiguo Sun Xiaoyan Ning Danyang Tian 《China Communications》 SCIE CSCD 2017年第8期184-194,共11页
Sine Non-linear Chirp Keying(SNCK) is a kind of high-efficient modulation scheme, which provides a potential new beamforming method in communication and radar systems. It has been proved to have advantages in some par... Sine Non-linear Chirp Keying(SNCK) is a kind of high-efficient modulation scheme, which provides a potential new beamforming method in communication and radar systems. It has been proved to have advantages in some parameter estimation issues over conventional modulation schemes. In this paper, a novel transform termed as Discrete Sinusoidal Frequency Modulation transform(DSFMT) is proposed. Then, the DSFMT of SNCK signal is deduced and classified into three types, based on which, the time-bandwidth product is estimated by the proposed algorithm. Simulation results show that the noise has a signifi cant impact on the localization of the peak value and the time-bandwidth product can be estimated by using local ratio values when. 展开更多
关键词 parameter estimation time-bandwidth product sine non-linear chirp keying(SNCK) discrete sinusoidal frequency modulation transform(DSFMT)
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Suspended Solids from Drained Peatlands in the East Coastal Zone of New Brunswick: Point Estimates and Climate Effects on the Environment
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作者 Mathieu Quenum Marion Tetegan Papa Malick Sail 《Journal of Environmental Science and Engineering(A)》 2015年第1期1-13,共13页
Peatlands represent one of the most important economic resources and abandoned peatlands after mining can be considered as ecological resources by re-vegetation restoration or management. However, some environmental p... Peatlands represent one of the most important economic resources and abandoned peatlands after mining can be considered as ecological resources by re-vegetation restoration or management. However, some environmental problems like particles from peatlands and their effects in the water system have to be characterized. Since centuries, artificial drainage has been a current practice for the mining of peatlands. Mainly mined for horticultural purpose, New Brunswick's peatlands--predominantly located in the eastern of the province--cover about 140,000 ha. At the downstream end of the drainage system, the water from peatlands flow into sedimentation basins. Drainage waters are often laden with solid particles. Once they have flowed through the ponds to allow sediment settling, the water is released into the water system. This paper describes the spatio-temporal evolution of suspended solids from 12 New Brunswick drained peatlands. The studied sites were characterized by some heterogeneity in the concentration of suspended solids. This study also provides knowledge on the suspended solids amount that can be released by drained peatlands, and it proposes a function to estimate the concentration of suspended solids by using climate variables; and identifies some potential ecological risks. 展开更多
关键词 PEATLANDS drainage sedimentation ponds suspended matters water system.
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Typical Ecotones in China 被引量:4
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作者 高吉喜 吕世海 +1 位作者 郑志荣 刘军会 《Journal of Resources and Ecology》 CSCD 2012年第4期297-307,共11页
An ecotone is a transition area between two biomes or two different ecosystems and are often fragile, sensitive and variable. Since the 1970s, the study of the ecotone has increasingly gained notoriety as an important... An ecotone is a transition area between two biomes or two different ecosystems and are often fragile, sensitive and variable. Since the 1970s, the study of the ecotone has increasingly gained notoriety as an important facet of ecological research. China, with a vast complex geology, climate and vegetation, is home to a variety of ecotones. This variety is witnessed in breeds, scales and sizes. This vast array has not only laid a solid foundation for scientific research but also enhanced China’s economic development, social development and cultural diversity conservation. According to the geographical distribution and ecological features of China’s large scale ecotone, "The trinity index system" has been established including land use types, natural climate characteristics and agricultural economic development to classify and define the spatial distribution of typical ecotones in China. Based on this classification, the natural environmental characteristics, environmental fragility and the existing problems of five kinds of typical ecotones have been studied. This study will lead to a comprehensive understanding of the evolutionary patterns of ecotones. 展开更多
关键词 ECOTONES CLASSIFICATION CHARACTERISTICS existing problems and countermeasures
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Resources, Environment and Economic Patterns and Sustainable Development Modes of the Silk Road Economic Belt 被引量:5
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作者 董锁成 李泽红 +6 位作者 李宇 石广义 于会录 王卷乐 李俊 毛琦梁 黄永斌 《Journal of Resources and Ecology》 CSCD 2015年第2期65-72,共8页
The paper analyzes the distribution pattern of resources, ecological environment, society and economy, and holds that it is conducive to Silk Road countries to carry out Omni-directional and multi-level economic coope... The paper analyzes the distribution pattern of resources, ecological environment, society and economy, and holds that it is conducive to Silk Road countries to carry out Omni-directional and multi-level economic cooperation. Then the article puts forth main modes and paths of sustainable economic development for the Silk Road Economic Belt (SREB): ecological civilization mode, regional economic integration mode, transportation economic belt mode and international tourism economic zone mode. Finally, the article summarizes the key scientific issues for the sustainable development in the SREB and puts forward several action projects which include establishing International Scientists League and Think Tanks, establishing international information sharing platform and scientific policy-making system of ecological environment and sustainable development of the SREB, starting international science cooperation and technology traineeship program of the SREB, founding the international cooperation committee in the SREB and founding transnational construction and win-win cooperation mechanism of coping with climate change and ecological environment. 展开更多
关键词 RESOURCES environment and economic patterns economic cooperation sustainable development keyscientific issues Silk Road Economic Belt (SREB)
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