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1.
《一朵小云》(A Little Cloud),是爱尔兰现代派小说家詹姆斯·乔伊斯(James Joyce)的短篇小说集《都柏林人》(Dubliners)中的一篇小说。学者们普遍认为文章标题"一朵小云"象征着生活的甘霖。笔者通过仔细研读、反复推敲、研究,最终得出:"一朵小云"另有一层象征意思。就是借助云的易幻变的特征,象征着主人公的思绪的漂浮与想象,他的希望、梦想如同空中的小云朵,不断在变化中,变成各种美好的图案浮现在眼前,但实质上只是精神世界的幻想,就像海市蜃楼一般,必将消失破碎。而"云"最终化为了"雨",也就是结尾主人公小钱德勒因为幻想彻底的破灭,而流下的眼泪。 相似文献
2.
Video streaming services are trending to be deployed on cloud. Cloud computing offers better stability and lower price than traditional IT facilities. Huge storage capacity is essential for video streaming service. More and more cloud providers appear so there are increasing cloud platforms to choose. A better choice is to use more than one data center, which is called multi-cloud. In this paper a closed-loop approach is proposed for optimizing Quality of Service (QoS) and cost. Modules of monitoring and controlling data centers are required as well as the application feedback such as video streaming services. An algorithm is proposed to help choose cloud providers and data centers in a multi-cloud environment as a video service manager. Performance with different video service workloads are evaluated. Compared with using only one cloud provider, dynamically deploying services in multi-cloud is better in aspects of both cost and QoS. If cloud service costs are different among data centers, the algorithm will help make choices to lower the cost and keep a high QoS. 相似文献
3.
BREED Dan 《科学通报(英文版)》2011,56(1):76-83
The Real-Time Four-Dimensional Data Assimilation (RT-FDDA) system is used for orographic snowpack enhancement.The model has three nested domains with the grid spacing of 18,6 and 2 km.To evaluate the simulations of winter orographic clouds and precipitation,comparisons are made between model simulations and observations to determine how the model simulates the cloud distribution,cloud height,cloud vertical profiles and snow precipitation.The simulated results of the 02:00 UTC cycling with 2-km resolution are used in the comparison.The observations include SNOTEL,ceilometer,sounding and satellite data,from the ground to air.The verification of these observations indicates that the Weather Research and Forecast (WRF) RT-FDDA system provides good simulations.It is better to use data within the forecast period of 2-16 h simulations.Although the horizontal wind component near the ground has some bias,and the simulated clouds are a little higher and have a little more coverage than observed,the simulated precipitation is a little weaker than observed.The results of the comparison show that the WRF RT-FDDA model provides good simulations and can be used in orographic cloud seeding. 相似文献
4.
In this paper, we present a novel, dynamic collaboration cloud platform in which a Combinatorial Auction(CA)-based market model enables the platform to run effectively. The platform can facilitate expense reduction and improve the scalability of the cloud, which is divided into three layers: The user-layer receives requests from end-users, the auction-layer matches the requests with the cloud services provided by the Cloud Service Provider(CSP), and the CSP-layer forms a coalition to improve serving ability to satisfy complex requirements of users.In fact, the aim of the coalition formation is to find suitable partners for a particular CSP. However, identifying a suitable combination of partners to form the coalition is an NP-hard problem. Hence, we propose approximation algorithms for the coalition formation. The Breadth Traversal Algorithm(BTA) and Revised Ant Colony Algorithm(RACA) are proposed to form a coalition when bidding for a single cloud service in the auction. The experimental results show that RACA outperforms the BTA in bid price. Other experiments were conducted to evaluate the impact of the communication cost on coalition formation and to assess the impact of iteration times for the optimal bidding price. In addition, the performance of the market model was compared to the existing CA-based model in terms of economic efficiency. 相似文献
5.
With the rapid popularity of cloud computing paradigm, disaster recovery using cloud resources becomes an attractive approach. This paper presents a practical multi-cloud based disaster recovery service model: DR- Cloud. With DR-Cloud, resources of multiple cloud service providers can be utilized cooperatively by the disaster recovery service provider. A simple and unified interface is exposed to the customers of DR-Cloud to adapt the heterogeneity of cloud service providers involved in the disaster recovery service, and the internal processes between clouds are invisible to the customers. DR-Cloud proposes multiple optimization scheduling strategies to balance the disaster recovery objectives, such as high data reliability, low backup cost, and short recovery time, which are also transparent to the customers. Different data scheduling strategies based on DR-Cloud are suitable for different kinds of data disaster recovery scenarios. Experimental results show that the DR-Cloud model can cooperate with cloud service providers with various parameters effectively, while its data scheduling strategies can achieve their optimization objectives efficiently and are widely applicable. 相似文献
6.
Analyzing global trends of different cloud types and their potential impacts on climate by using the ISCCP D2 dataset 总被引:7,自引:0,他引:7
DINGShouguo SHIGuangyu ZHAOChunsheng 《科学通报(英文版)》2004,49(12):1301-1306
The International Satellite Cloud Climatology roject (ISCCP) D2 dataset is used to study the global distribution of low, middle and high cloud amounts and their rends of 1983-2001. Evidences have shown that global arming has accelerated over the past 20 a and the 1990s as the warmest decade in the instrumental records since 861. Trends of various clouds amounts over this period are nalyzed by employing the linear regression method. The esults show that global mean total cloud amounts, in general,have tended to reduce over the past 20 a. But there are lightly increasing by about 2% before 1987 and decreasing y about 4% since then. Cloudiness trends of both low and igh clouds decrease while increase for the middle cloud.And there exist remarkable discrepancies in different regions.The preliminary analyses suggest that it is likely that the loud change occurring over the past 20 a is a positive feedback to global warming. 相似文献
7.
试析詹姆斯·乔伊斯的《伊芙琳》的写作技巧 总被引:1,自引:0,他引:1
分析了詹姆斯·乔伊斯在小说《伊芙琳》中所运用的“精神顿悟”法、内心独白法和象征等写作技巧,特别是重点分析了其中的“精神顿悟”法,这种方法无疑为后来的意识流小说奠定了基础,也是我们全面解读乔伊斯作品的重要依据。 相似文献
8.
A data center is an infrastructure that supports Internet service. Cloud comput the face of the Internet service infrastructure, enabling even small organizations to quickly ng is rapidly changing build Web and mobile applications for millions of users by taking advantage of the scale and flexibility of shared physical infrastructures provided by cloud computing. In this scenario, multiple tenants save their data and applications in shared data centers, blurring the network boundaries between each tenant in the cloud. In addition, different tenants have different security requirements, while different security policies are necessary for different tenants. Network virtualization is used to meet a diverse set of tenant-specific requirements with the underlying physical network enabling multi-tenant datacenters to automatically address a large and diverse set of tenants requirements. In this paper, we propose the system implementation of vCNSMS, a collaborative network security prototype system used n a multi-tenant data center. We demonstrate vCNSMS with a centralized collaborative scheme and deep packet nspection with an open source UTM system. A security level based protection policy is proposed for simplifying the security rule management for vCNSMS. Different security levels have different packet inspection schemes and are enforced with different security plugins. A smart packet verdict scheme is also integrated into vCNSMS for ntelligence flow processing to protect from possible network attacks inside a data center network 相似文献
9.
The Kepler General Purpose GPU (GPGPU) architecture was developed to directly support GPU virtualization and make GPGPU cloud computing more broadly applicable by providing general purpose computing capability in the form of on-demand virtual resources. This paper describes a baseline GPGPU cloud system built on Kepler GPUs, for the purpose of exploring hardware potential while improving task performance. This paper elaborates a general scheme which defines the whole cloud system into a cloud layer, a server layer, and a GPGPU layer. This paper also illustrates the hardware features, task features, scheduling mechanism, and execution mechanism of each layer. Thus, this paper provides a better understanding of general-purpose computing on a GPGPU cloud. 相似文献
10.
In Cloud computing,data and service requests are responded by remote processes calls on huge data server clusters that are not totally trusted.The new computing pattern may cause many potential security threats.This paper explores how to ensure the integrity and correctness of data storage in cloud computing with user’s key pair.In this paper,we aim mainly at constructing of a quick data chunk verifying scheme to maintain data in data center by implementing a balance strategy of cloud computing costs,removing the heavy computing load of clients,and applying an automatic data integrity maintenance method.In our scheme,third party auditor (TPA) is kept in the scheme,for the sake of the client,to periodically check the integrity of data blocks stored in data center.Our scheme supports quick public data integrity verification and chunk redundancy strategy.Compared with the existing scheme,it takes the advantage of ocean data support and high performance. 相似文献
11.
12.
戴怀德 《河南师范大学学报(自然科学版)》1983,(2)
在原子核的(n,γ)反应中,将受激核看作是由角动量为1的 p-h 整玻色子所组成的“海”、“云”二相系统,在能量简并的情况下,“海”相耦合为巨共振,进一步考虑单粒子和集体态间的相互作用后,简并“解除”并形成亚稳态的连续能级分布。γ—光子穿透云区时产生共振散射而形成5.5MeV 矮共振,对光子强度函数进行计算的结果表明,理论计算与实验的符合程度是令人满意的。 相似文献
13.
为了研究爆炸及燃烧产生的"蘑菇状"烟团的产生机理,在实验室中通过点燃预混过量乙烯和氧气的气泡,产生瞬时燃烧的火球和烟团。纹影法和高速CCD相机直接拍摄法显示瞬时燃烧火球上升时,迅速形成一具有涡环结构的烟团。采用中尺度气象模式RAM S模拟计算相同尺度加热烟团的流动过程。计算机模拟显示产生涡环形状的烟团现象与初始烟团的形状无关,与初始热源温升也无关。浮力涡环产生的机理应是流体的斜压性,即在有重力的条件下浮力的水平差别造成的涡度生成;涡度生成应在轻流体与环境流体相交的侧边界附近。 相似文献
14.
在对伊通地堑三维地震资料进行系统的构造解析的基础上 ,结合区域地质和钻井资料 ,对伊通地堑构造样式进行了详细的解剖 ,并简要分析了不同构造样式的油气分布规律 .结果表明 ,伊通地堑构造样式以“基底卷入型”为主 ,从盆地的动力学机制上属于“走滑 -拉分型”,进一步可概括为5个类型构造样式 ,分别是 :台阶式断块型、掀斜反转型、简单掀斜型、不对称双断型和伸展断块型 ,而且每一个断陷都以一种构造样式占主体 ,其展布具有明显的规律性 .构造样式的差异是造成不同断陷具有独特油气分布规律的主导因素 相似文献
15.
《水浒传》是对“义气”文化的最好诠释。小说生动地表现了“替天行道”是“义”的根据、“济困扶危”“仗义疏财”是我们民族“义气”的基本内容、发现并尊重人才是“义”的最高表现形式,而且“义”还是团结人教育人的力量。 相似文献
16.
杨侠泉 《东莞理工学院学报》1995,2(2):47-52
企业要兴旺发达除内部管理有素之外,要有良好的市场环境,而良好的市场环境,需要领导者去创造。本文从“认识市场、把握自我”、“智勇兼备、开拓市场”、“就实避虚,严谨论证”、“灵活多变、出奇制胜”、“从长计议,静观动态”、“派兵点将,论功行赏”等6个方面,对小型企业的领导者如何从企业外部创造一个良好的市场环境问题进行了探讨。 相似文献
17.
本文是作者“量子力学的新解释”数篇系列文章的第2篇。在第1篇即文献[1]的基础上,提出了新的量子观点、并用于对原子分立能级和量子概念的物理本质进行新的解释:指出原子内部可能存在尚未被认识的物理性质,是产生原子分立能级的原因,分立能级之间还是有连续能量存在。提出了“电子内力”、“粒子内力”、“综合内力”和“原子第一宇宙速度”等新假设,并用于重新计算具有连续能量的原子分立能级,计算数据与实验相符,说明计算所根据的理论是正确的。还为上述各种新的理论观点提供了实验根据。进一步的理论和实验方案将在以后的多篇论文中论述。 相似文献
18.
中介谓词逻辑系统MF的无穷值语义解释,反映了反对对立概念之间的可变过程,并且该解释不同于MF的其他任何语义解释。但在该无穷值语义解释下,"当A fuz时~A真"这种情况并未得到反映。在此基础上,进一步研究得到了中介谓词逻辑系统MF一种真值域为[0,1-λ)∪(1-λ,λ)∪(λ,1](λ∈(0.5,1))的无穷值语义解释,重新定义了MF的文字,给出了MF中λ-互补文字及弱无中介集的定义,提出了一种新的MF的λ-归结原理,并证明了其可靠性和完备性。在改进的MF的无穷值语义解释下,不仅较好的表达了"当A fuz时~A真"的情形,而且其λ值的确定,可根据一定的实例知识计算出来,具有客观性。该解释进一步表明用中介逻辑作为模糊知识的表示与推理的工具是可行的。 相似文献
19.
学导式教学既是一种教学方法。又蕴涵着一种新的教学论思想。它既强调"学",这种"学"是学生的自学或教师指导下的独立学习;又注重"导",这种"导"是使学生个性得到充分发挥的启发和引导。学导式教学同成人教育的教学特点非常契合,这种教学方法在成人教育中有着广泛的发展空间。 相似文献
20.
以一部音乐剧场作品《城市迷阵》为例,从听觉角度研究了"虚拟-现实"的情境式剧场空间设计.通过对设计方法、编排过程、实施的细节等诸多方面的记录和研究,从声音设计的角度提出了驻场演出中3D声音展现的方式、设计方法和应用成果. 相似文献