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1.
在假设输入光场为单模相干场,原子制备在最高激发态的条件下,运用全量子论方案研究了Kerr介质中一个级联三能级原子布居随时间演化特点。结果表明:当单光子失谐量较大时,改变输入光场强度可以实现原子跃迁转移。文中对该现象给出了一种解释。  相似文献   

2.
用全量子论研究了初始处于最高激发态放置于充满Kerr介质腔中的级联型三能级原子与单模腔场互作用系统的腔场谱。与二能级原子不同,文中讨论的模型中真空场的Rab i劈裂也会受到Kerr非线性的影响。若腔场初始处于Fock态,腔场与Kerr介质耦合较弱时,Kerr效应主要表现在使谱不对称及影响谱峰数目方面,当腔场与Kerr介质耦合较强时时,Kerr效应主要表现在使对应于无介质腔的中心共振峰远离共振频率。若腔场初始为热光场,腔场谱依Kerr效应强弱可为连续谱或分立谱。  相似文献   

3.
通过严格解主方程求出耗散腔中级联三能级原子密度矩阵,研究了初始处于真空耗散场中三能级原子偶极平方压缩效应.假设原子初始处于基态与最高激发态的相干叠加态,并在共振相互作用条件下,系统在演化过程中可以出现原子偶极平方压缩现象.结果表明,理想腔条件下压缩量呈现周期性变化,当存在耗散项时,腔耗对原子的压缩效应有显著削弱作用.  相似文献   

4.
用时间演化算符方法研究了理想腔中近简併Λ型三能级原子在微波驱动场作用下的发射谱.讨论了增大或减弱驱动微波场对原子发光谱的影响,及谱对Λ型三能级原子两个下能级裂距的依赖关系.  相似文献   

5.
通过改变激光在铝合金上聚焦时的光束偏移距离,对4 mm的Ti/Al异种合金进行焊接.焊后测试了不同参数条件下接头的力学性能,观察并分析了Ti/Al界面的微观组织形貌.试验结果表明:激光偏转角度为10°,光束偏移距离分别为1.1、1.2 mm时,Ti/Al界面处分别形成约30、10μm的扩散层,此时断裂形式为脆断;光束偏移距离为1.3 mm时,Ti/Al界面处形成了约0.8μm的扩散层,其主要成分为TiAl_2、TiAl、Ti_3Al金属间化合物,此时断裂形式为韧断,接头的抗拉强度最高,为192 MPa,达到铝合金母材强度的63%.  相似文献   

6.
采用激光焊,通过改变激光在钛合金上聚焦时的光束偏移量,焊接了5mm的Ti3Al2.5V/6063异种合金.焊后测试接头抗拉性能,观察并分析了Ti/Al界面的微观组织形貌.试验结果表明:光束偏移量(D)在0.8mm≤D≤1.0mm范围时,Ti/Al界面处形成了固体钛层;当光束偏移量D=1.0mm时,接头的抗拉强度达到最大值132MPa,为铝合金母材强度的53%;通过对接头的微观组织分析,焊缝界面处的相主要是AlTi、AlTi_3、Al_2Ti、Al_3Ti,固体钛层的存在一定程度上降低了界面反应程度.  相似文献   

7.
研究了Kerr介质腔中相干态单模场与级联三能级原子共振相互作用系统中量子保真度的演化特性.结果表明,对真空初场,原子、场及系统保真度都呈现调制周期振荡;对不依赖强度的原子-场耦合系统,增大Kerr效应或增强初场强度都能提高原子的量子保真度,在原子量子保真度复苏时区同时提升场和系统的量子保真度,但对依赖强度耦合系统却无此作用.  相似文献   

8.
用时间演化算符方法研究了理想腔中近简饼∧型三能级原子在微波驱动场作用下的发射谱。讨论了增大或减弱驱动微波场对原子发光谱的影响,及谱对∧型三能级原子两个下能级裂距的依赖关系。  相似文献   

9.
为了揭示腔内原子偶极压缩性质随时间的演化规律,采用全量子理论研究了与单模相干光场相互作用的Λ-型三能级原子的原子偶极压缩参量与相互作用时间的关系,讨论了初始相干光场强度、初始原子相干性、初始原子下能级布居以及两下能级劈裂对原子偶极压缩效应的影响.结果表明原子偶极压缩量随初始光场强度增大而增加,但压缩时间缩短.若原子两下能态简并,则该两能态初相及布居相同时压缩最深.交换两下能级布居对偶极压缩时间演化无影响.在一定条件下能级劈裂有利于原子偶级压缩的产生.  相似文献   

10.
程立  汪家春  周瑞 《舰船电子工程》2012,32(12):113-115
激光探针诊断技术作为一种等离子体主动诊断技术,在等离子体参数诊断中具有其独特的优势。文章综述了激光作为探针诊断等离子体参数的干涉诊断技术、摩尔偏折诊断技术以及Thomson散射诊断技术,分别介绍了各种技术的原理和一般方法。  相似文献   

11.
Errata     
正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.  相似文献   

12.
13.
正San Francisco,California,June 8-13,2014.OMAE 2014 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to:·meet and present advances in technology and its scientific support;·to exchange ideas and experiences whilst promoting technological progress and its application in industry·to promote international cooperation in ocean,offshore and arctic engineering.In line with the tradition of excellence of previous OMAE conferences,more than 900 technical papers are planned for presentation.Outreach for Engineers Specialty Forum This Specialty Forum is designed for students and professionals who may not be familiar with the Ocean and Offshore industry,as well as those who have just recently specialized in this field.  相似文献   

14.
联合作战计划和执行系统   总被引:2,自引:1,他引:1  
全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划:时间不限的精密预案计划生成作战计划、方案计划或职能计划;时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础,加速应付危机的能力。  相似文献   

15.
Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.  相似文献   

16.
正19–24 October 2014 SingaporeCONFERENCE THEMES The overall aim of the ICHD Conference is to provide a forum for participants from around the world to review,discuss and present the latest developments in the broad discipline of hydrodynamics and fluid mechanics.The first International Conference on Hydrodynamics(ICHD)was initiated in 1994 in Wuxi,China.Since then,9 more ICHD conferences were held subsequently in Hong Kong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,Shanghai and St Petersburg.Evidently the ICHD conference has become an important event among academics,researchers,engineers and operators,working in the fields closely related to the science and technology of hydrodynamics.The 11th ICHD will be held in Singapore in 2014.  相似文献   

17.
正November 4-6,2014Moody Gardens HotelConvention Center/Galveston,TX The Deepwater Operations Conference and Exhibition is celebrating its 12th anniversary this year.This growing event will continue the tradition of excellence in addressing operational challenges involved in developing deepwater resources.We will return to the Moody Gardens Hotel and Convention Center on November 5-7,2014 in Galveston,Texas.  相似文献   

18.
In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama?
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou).  相似文献   

19.
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.  相似文献   

20.
依据码头撞击受损区域调查检测结果,对受损构件提出合理的修复方案,为码头的安全运行提供保障。  相似文献   

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