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1.
针对购物篮、自行车等比较常见的环保公用物品的流转,设计了一个网络式构架的公用物品流转平台,此平台由流转终端和服务中心两部分组成。流转终端采用了嵌入式ARM芯片S3C2410A作为主板,开发测试过程用Embest EDUKIT-III实验开发系统作为实验板、开发板,仓库设计独特。目前这一平台成功应用于自行车租赁系统。  相似文献   

2.
李惠军  赵凯 《山东科学》2003,16(3):42-46
本文介绍了集成电路工艺设计仿真平台的系统集成及交互功能设计等技术实现。该系统成功地使用诸多VB-API函数。完成了集成电路工艺设计仿真平台的系统集成研究。其研究与开发路线对实现适时性的CAD仿真环境的系统集成开发具有一定的可借鉴性。  相似文献   

3.
针对松木在不同条件下热解的失重规律,用热重分析法对松木的热解失重过程进行了系统研究。分析了松木样品在不同升温速率(5、10、20、30℃/min)和不同温度(200、250、300、350、400℃)条件下恒温4h热解的实验结果,发现松木样品的非等温失重过程由脱水、保持、剧烈失重和缓慢失重4个阶段组成,并且在相同条件下样品的质量对松木的热解过程有一定的影响。在恒温热解过程中,不同的恒温温度条件其失重曲线形态基本相似,但在200、250、400℃条件下恒温热解的热重曲线与300、350℃条件下恒温热解的热重曲线相比较较为平缓。研究结果,为研究松木的热解反应动力学模型及对其合理利用提供了一定的理论基础。  相似文献   

4.
微小卫星编队飞行仿真平台设计   总被引:3,自引:0,他引:3  
为了进行微小卫星编队飞行设计,设计了一个仿真平台。该仿真平台由两颗模拟卫星和控制中心组成,通过星间RF设备和网络控制器形成三节点星间网络,并可以根据需要增加模拟卫星的数量。模拟卫星载有多个物理的敏感器和执行器,能够对其性能进行测试。在此平台上设计了双星主从控制、双星协同控制、三星主从控制、三星协同控制、单星失效模式等多种控制策略。通过GPS伪距差分技术进行相对定位外场实验,给出了编队飞行控制仿真所需的相对定位精度,同时也验证了星间网络的功能和可靠性。  相似文献   

5.
煤自燃影响因素的热重分析   总被引:3,自引:0,他引:3  
采用德国耐驰公司的TG209热重分析仪,针对在不同粒度、不同供氧浓度和不同升温速率的实验条件下,开展热重分析实验研究。通过对煤样氧化过程失重和失重速率曲线的分析,表明特征温度点可以从宏观上反映出煤样氧化微观过程中外界条件对反应过程的影响,并研究了不同实验条件对特征温度点和失重值的影响规律。  相似文献   

6.
在多飞行器航迹动态协同规划方法方面,已经初步完成飞行器自主控制与机动调控飞行演示系统和微型无人旋翼飞行器(直升机、四旋翼)的实验平台。在环境和飞行轨迹给定的条件下,该系统可以演示多飞行器的航迹规划效果。在此基础上提出了一些约束条件下多飞行器航迹动态协同规划方法,以满足低空复杂飞行的需求  相似文献   

7.
中科院重庆绿色智能技术研究院4月18日对外宣布,由该院和中科院空间应用工程技术中心共同研制的国内首台空间3D打印机,已经在法国波尔多成功完成抛物线失重飞行试验,能够在微重环境下完成3D打印. 据中科院重庆研究院3D打印技术研究中心主任段宣明介绍,该打印机最大零部件尺寸达200× 130 mm,是美国国家航空航天局首台空间在轨打印机打印尺寸的2倍以上.今年3月上旬,该打印机在法国波尔多进行了抛物线失重飞行试验.  相似文献   

8.
基于SOA的网络教学资源系统集成   总被引:2,自引:0,他引:2  
传统的网络教学资源系统由于在平台、开发工具和系统上是紧耦合的,这导致了各种网络教学资源系统的分散和独立。而面向服务的SOA具有松耦合性,与平台、语言无关性等特点,可以快速、有效地整合网络教学资源系统。分析、探讨了网络教学资源系统的工作现状、SOA的概念和体系结构,提出了基于SOA的网络教学资源系统集成框架,并给出了一个成功的网络教学资源系统集成案例,实现了网络教学资源系统的集成和软件复用。  相似文献   

9.
利用小扰动飞行动力学方程和参数敏感性分析方法,研究了某非圆截面导弹在典型气动条件下的开环飞行稳定特性.对该导弹在不同静、动导数条件下的飞行稳定性进行了研究,得到了影响系统稳定性的主要因素以及出现较优横侧向稳定性的参数取值区间,这些结论为同类型导弹气动布局和控制系统的设计提供可靠的借鉴.  相似文献   

10.
地面失重实验系统的控制器设计   总被引:2,自引:0,他引:2  
主要讨论在地面上模拟空间微重力环境时,地面失重实验系统的控制器设计.从目标物体的静止和运动两种情况,分析了目标物体碰撞后的运动学关系,在垂直方向上通过恒张力控制来模拟目标物体太空失重的状态,提出了在极坐标下对碰撞后的目标物体进行偏转角度和偏转位移的跟踪,保证移动机器人和捕获目标在一个平面.给出了对应的驱动电机的数学模型,针对模型中不确定参数的控制,采用优化后的模糊小脑模型的控制器构成一种自学习控制器,并对带有未知负载干扰的失重系统进行实验研究.仿真实验结果表明,该控制器具有较强的鲁棒性以及良好的跟踪特性.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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