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1.
Sukhchain  B. S. Sidhu 《Euphytica》1992,64(1-2):59-63
Summary Phenotypic and genotypic correlation coefficients of total crude protein per plant (TCP) and digestible dry matter per plant (DDM) with dry matter yield per plant (DMY), tiller number, plant height, stem thickness and leaf-stem ratio, pooled over two years, revealed that TCP and DDM were correlated at both the phenotypic and genotypic levels with DMY, tiller number and plant height. But only DMY had high direct effects on TCP and DDM. Tiller number and plant height had only indirect effects on TCP and DDM via DMY. Thus, selection based on tiller number and plant height may not only improve dry matter yield per plant but also total crude protein per plant and digestible dry matter per plant. Further, screening of high TCP and high DDM clones among the high yielding clones would be a more remunerative approach to improve TCP and DDM in Guinea grass.  相似文献   

2.
Based on comparing with the existing parallel algorithms for mining association rules, the paper analyzes CD,FDM,DDM algorithm in details. To overcome problems existing in efficiency of candidate sets pruning and execution time of these algorithms, the paper proposes parallel process algorithm with an improved parallel association rules. Finally the result of test on share-nothing cluster of workstation show that after adopting the improved algorithm, execution performance and efficiency are higher than others. This result indicates that the algorithm has achieved algorithm optimization.  相似文献   

3.
OGSA, as a universal grid computing frame, has resolved a good many problems in the CSCD, and provides a new solution for the network-based collaborative design. This paper studied the main problems in application of the grid technology to network-based collaborative design system by the OGSA based the WSRF, which is used as the basic platform of collaborative design grid. The meaning of the collaborative design grid is explained, and then the opening architecture of collaborative design grid design process on the condition of eoll is presented based on the function analysis in detail. Meanwhile, the collaborative aborative design grid is explained, and the key technologies of the collaborative design grid are analyzed deeply. The results provide a solution and groundwork for the more research on the collaborative design grid and its implementation.  相似文献   

4.
Apache Struts is one of the most popular open source framework for Web applications and developments using MVC Model2 architectural pattern. Using the Information Technology to improve the efficiency of education service is emergent. The aim of this paper is to demonstrate the design and realization of a platform system software based on Apache Struts framework. By briefly analyzing the extra requirement in higher education service, an architecture based on MVC design pattern is presented. Some core technologies used in the platform system software, such as Struts Tiles and Struts Menu etc, are proposed in details by the end. Because of its struts-based fundamental architecture and running mechanism, the platform system software made a certain performance advantage and largely reduced the developing period.  相似文献   

5.
Evaluation of plant species for animal feed requires the quantitative and qualitative comparison of different genotypes. Promising lines of annual legumes comprising seven genotypes of vetche ( Vicia spp.) and chicklings ( Lathyrus spp.) were compared for herbage quality. The content of crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) in herbage and pods were measured at different stages of plant maturity. The proportion of the leaves to shoots (leafiness) and in vitro dry matter digestibility (IVDMD) were also determined. As plants matured IVDMD, CP and leafiness decreased and NDF and ADF increased. For all the genotypes maximum digestible dry matter (DDM) and CP yields were more or less attained at 50–100 % podding. Narbon vetch had the highest DDM. The possible uses of the different genotypes as animal feed are discussed based on the partitioning of the DDM and CP yield as plants matured.  相似文献   

6.
为了应对林业资源信息管理在大数据时代面临的新机遇和挑战,解决智慧林业中林业资源信息服务体系架构设计与应用问题,基于云计算理论与技术,深入剖析了林业资源信息云服务的内涵及其基本特征,参照IEEE 1471 2000提出了林业资源信息云服务架构设计元模型,进而借鉴架构模式中的层架构模式设计思想,初步设计了林业资源信息云服务体系架构的总体结构和分布式协同部署模式,在国家林业局和辽宁省开展的林业资源监管服务系统构建过程中对体系架构的理论设计结果进行了实践应用和反馈修正。结果表明,林业资源信息云服务体系架构能够满足大数据环境下林业资源监管业务需求,具有良好的实用性和推广性。  相似文献   

7.
With the rapid increasing interaction between wind turbines and power systems, wind turbines have to have the fault ride-through (FRT) capability to ensure the safe operation of power grid. In order to improve the asymmetric FRT capability of permanent magnet synchronous generator (PMSG) wind turbine, a novel control FRT method based on super-capacitors is proposed. In this method, super-capacitors are connected to the DC bus of AC-DC-AC converter via a bi-directional DC-DC converter, and the power processed by the super-capacitors is controlled to limit the increasing of the DC bus voltage of the AC-DC-AC converter in grid failure condition, and to reduce the 2nd order voltage ripple in the DC bus. Meanwhile, the proposed control method employs the grid voltage feed-forward approach to reduce the negative sequence current component in the grid side converter. According to the low voltage ride through (LVRT) standard, the selection of the super-capacitor capacity is also discussed, and then a mathematical model of the super-capacitor with the bi-directional DC-DC converter is established for designing the controller. Simulation results for a 1MW PMSG wind turbine by MATLAB show that the proposed control method reduces both the negative sequence current component in grid side converter and the 2nd order voltage ripple in DC link at the same time. The results also demonstrate that the asymmetric FRT capability of PMSG wind turbine is improved, which verifies the effectiveness of the proposed control method in this paper.  相似文献   

8.
The relationship between architecture and people, architecture and city, architecture and nature has always been the soul of architectural design. In the architectural design, study on the relationship between architecture and nature needs "site analysis"(mapping), and "natural environment" tends to affect the design results[1]. In many special areas, the design needs analysis of geology, geomorphology, hydrology, vegetation and other landscape elements. Coal mining subsidence area is the product of the conf licts between human activities and natural environment in the process of industrialization. As the research object, coal mining subsidence area can be a good study object to demonstrate architectural design strategies and methods based on landscape, and fi eld defects of the site may be the origin of architectural space organization: architectural concept, structure, morphology, spatial organization are all from the landscape elements.  相似文献   

9.
基于数据挖掘的生态公益林效益评价决策支持系统研究   总被引:2,自引:1,他引:1  
生态公益林效益评价是生态公益林系统管理与可持续发展的重要内容。在生态公益林效益评价的主要内容与价值量评估公式、参数设置及方法的基础上,给出了基于数据挖掘的生态公益林效益评价决策支持系统的功能结构与体系结构;设计了以模型库与知识库为中心,辅以数据库、方法库和计算机网络技术的生态公益林效益评价决策支持系统;利用软件工程方法、J2EE框架技术、MVC设计模式和数据库访问技术实现系统开发。系统利用数据挖掘中聚类分析技术,能进行生态公益林资源分类和关联规则技术挖掘出公益林不同效益指标之间的内在联系。系统具有较强的分析、预测与决策、可视化输出功能,辅助生态公益林管理与决策者提高决策水平和质量。  相似文献   

10.
11.
This paper proposes a control scheme for a doubly-fed induction generator (DFIG) wind farm with VSC-HVDC grid integration to ensure secure and reliable operation of power system with fluctuated wind power penetration. The whole system dynamic models are respectively described. Based on vector control system with a virtual voltage orientation, a steady-state voltage control block and a dynamic voltage control block with a cross-product term of d-q currents are separately designed for WFVSC to control the corresponding parts of the wind farm voltage. Meanwhile, with the consideration of AC and DC side parameter variation and external disturbance, an improved backstepping control scheme with Lyapunov stability provement is also proposed for the GSVSC. The combination of the two schemes makes up the new control design of this study. Besides, to verify the performance of the proposed new control design, three different cases are suggested which contain the AC and DC side parameter variation and external disturbance such as local load cut off-in, grid voltage harmonics. Finally, numerical simulations using MATLAB/Simulink are presented for a 200MW DFIG wind farm with VSC-HVDC grid integration to validate the proposed control scheme and demonstrate the improved system operation performance. Moreover, the corresponding discussions are also presented for further illustrations.  相似文献   

12.
Process communication based power distributed computing model satisfies the demand on real time monitoring and analysis for the economical operation of power grid based on power distributed computation methods, but there are some problems on complexity in common basic functions development and lack of system extendibility. An extendable services-oriented power distributed computation system model is designed and implemented. Software design patterns are applied to design low coupling and extendable system framework. Windows Communication Foundation (WCF) technology is used to implement the services-oriented distributed data communication functions. Windows Workflow Foundation (WWF) technology is used to design the business logic of power distributed computation visually. Data integration functions are implemented by combining the ADO.NET technology. The services-oriented system architecture enhances the integration ability and extendibility. The use of WCF and WWF technology reduces the complexity of the system development.  相似文献   

13.
电网发生大面积冰灾情况时,多条输电线路存在覆冰故障隐患,电网稳定运行受到严重威胁,需要提前制定输电线路融冰方案,合理安排融冰顺序。针对此问题,分析输电线路覆冰继续运行给电网带来的停电风险,将与待融冰输电线路相关联的变电站的电气主接线展开,将传统削负荷模型改进后应用于输电网与变电站主接线的组合网络,建立断路器可靠性模型,计算靠后融冰线路因继续运行的电网停电风险;利用计及风速及降雨影响的输电线路覆冰增长预测模型,计算输电线路的覆冰率,根据覆冰率门槛值确定待融冰线路集,基于覆冰严重度模型构建系统全局的覆冰指数指标;综合考虑电网停电风险及系统全局覆冰指数建立输电线路融冰紧迫度指标,动态更新待融冰线路并决策融冰顺序。最后,以IEEE RBTS系统进行算例分析,验证了所提方法的可行性与合理性。  相似文献   

14.
With the explosion of semantic web technologies, large amounts of OWL ontologies are common place. Conventional rule engines inevitably meet the bottleneck of computing performance and scalability. A cloud computing based SWRL distributed reasoning framework named CloudSWRL is proposed. Based on the Hadoop open-source framework and SWRL semantics, the storage schema for OWL ontologies is designed to implement efficient data retrieving from HBase. Some novel data models for SWRL rules and intermediate data are defined. At last, a MapReduce paradigm based distributed SWRL reasoning algorithm is proposed under DL-safe restriction. An experiment on a simulation environment shows our framework is more efficient and scalable than conventional rule engines when reasoning over large-scale of OWL data.  相似文献   

15.
In order to solve the incipient fault diagnose problem of the transmission system, a networking condition monitoring and failure diagnosis system based on B/S and C/S hybrid architecture for wind turbine transmission system is designed in the paper. Firstly, the paper analyzes the demands of condition monitoring and fault diagnosis system for wind turbine transmission system, and designs its overall framework and function modules. Then, combining with the data acquisition equipment, by the .NET and SQL Server platform, the paper designs condition monitoring and failure diagnosis system for wind turbine transmission system, which includes the functions of networking data acquisition, remote condition monitoring, signal analysis, fault diagnosis and database as well. The system has been successfully applied to a condition monitoring and fault diagnosis of wind turbine transmission system.  相似文献   

16.
Owing to the special geographic environment and chronic historical accumulation,the Chinese nation has formed the national character mainly based on "renaissance ideology",which has exerted a profound influence on the forming and development of Chinese traditional architecture.By discussing the spatial pattern characteristics of country,cities,courtyards and geomantic omen,the authors indicate their common feature-enclosure,and summarize the spatial pattern of Chinese traditional architecture influenced by "renaissance ideology"-layer upon layer enclosure by bringing the spatial patterns of different layers into a unified framework.At the same time,the construction activity is extended to social culture so as to find out the correlation between the spatial pattern of Chinese traditional architecture and national character.  相似文献   

17.
The existing section function for mining subsidence prediction has several shortcomings, such as complex expression, uncertainty of coordinates origin and parameters in application. The features of observing data in the ground subsidence of rectangular goaf are studied and a new fit function of main section is proposed for mining subsidence prediction.This new function has some merit that the mathematical formula is simple and the parameter is also easy to identify in practices. It is proved that the results of this new function is fit well with on site survey .  相似文献   

18.
Quality Management Information System(QMIS) is critical component in enterprise quality system. The enterprise quality management of modern manufacture perform mostly as a dynamic system during continuous change. OMT(Object-oriented Modeling Technique) is adopted in this paper, QMIS is analyzed on the aspects of system analysis, system architecture, object model. The framework architecture of flexible ISO9000-QMIS and the universal feature is presented. With the design of flexibility and expandability, structure and function can be redesigned based on managing instance of enterprises, and satisfy the dynamic requirement of informationlization.  相似文献   

19.
This paper first presented the architecture of the CAD system for space - grid structures based on ObjectARX, then some key technologies were studied to realize the system, such as interface control method on MFC, graphic database and parametric drive. A CAD system for space -grid structures based on ObjectARX was develooed with AutoCAD API and the Object- oriented technique.  相似文献   

20.
农业信息资源上数据挖掘的应用   总被引:6,自引:2,他引:6  
【研究目的】通过应用数据挖掘技术解决农业信息领域“信息爆炸,但知识贫乏的问题”,提高农业资源的利用率。【方法】学习分析农业信息以及数据挖掘技术的特点。【结果】提出数据挖掘技术应用于农业具体领域的建议并架构农业数据挖掘系统,根据数据挖掘的流程及其相关技术,设计出具有3层机构的农业数据挖掘系统,并突出阐述每层的功能,其次介绍农业挖掘工具集的特点。【结论】以农业科学数据网数据库为背景,致力于在现有海量数据存储和强大计算能力的基础上,通过数据挖掘技术来进一步提升农业信息服务水平。  相似文献   

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