共查询到20条相似文献，搜索用时 31 毫秒
1.
The paper concludes the characters of methanol as a fuel in engines. Based on the kiva 3v program, it conducts the multi dimensional numerical simulation of the operation process in cylinder of a methanol fueled engine to obtain the detail information and performance graphic charts, as well as the real time data of pressure, temperature and so on. It is helpful for the research on methanol fueled engines. The results indicate that the methanol is a green alternative fuel and the methanol fueled engines have steady operations and lower emissions by comparing the numerical results with the data of gasoline engine. 相似文献
2.
3.
Along with the rapid increase in information of internet,the information research technology was confronted with more and more challenge.Traditional WEB search engine is not satisfied with users' special demand any more,therefore there comes forth a trend to join intelligent technique with Web search engine.This paper puts forward a Multi-agent based architecture for WEB search engine based on traditional architecture.An effective securities business search engine,which is can satisfy user's especial request which is created by means of intelligent technique.If the system is used in many other special fields,good results of information research can also be acquired. 相似文献
4.
There is a kind of combination of correlated objects in mechanical translation.When match the combination with the rule,the searching solution becomes un-possible by the"combinatorial explosion".A hierarchical intelligence search method is advanced.According to the prior knowledge,the data which do not satisfy the correlation constraint will be removed by the closed-loop eliminate method at first and then only a simple search in order is needed for obtaining the solution of the problem.This method refrains from any backtracking.The time and space consumed by search are greatly reduced. 相似文献
5.
文献计量分析在快速检索文献中的应用——以土壤氨挥发为例 总被引：1，自引：0，他引：1
为解决关注的研究领域中检索关键文献效率低的问题,本研究利用R语言bibliometrix包,以土壤氨(NH3)挥发为例,进行文献计量分析（包括关键词共现分析、共词分析及高被引论文分析）,探索文献计量分析在Web of Science核心数据库中精确快速检索文献的方法。研究发现,第一次文献检索时,输入少量简单关键词（土壤氨挥发）,检索出来的文献数量达到3573篇,且其中的高被引论文多数与主题词关系不大。对第一次检索结果进行文献计量分析,根据关键词聚类、共词分析结果,增加了关键词进一步检索文献,进行上述过程2次后,检索的文献数目已降至160篇,其中的Top 10高被引论文与检索主题（土壤NH3挥发）紧密相关。此时,假设需进一步精确查找关于土壤NH3挥发与水分、温度、管理方面研究文献,再次分别增加关键词进一步检索,分别检索出26、20和28篇相关文献,且关键词及高被引论文分析结果也再次验证了方法的准确性。本研究中利用文献计量分析快速检索权威、关键文献的方法切实可行。在大数据背景下,文献计量结合R-bibliometrix工具,有助于快速、精确地检索关键文献、获取科研思路及解决方法。 相似文献
6.
环保部2016年发布了GB 15097—2016《船舶发动机排气污染物排放限值及测量方法（中国第一、二阶段）》,该标准相较于《渔业船舶法定检验技术规则（船长大于或等于12 m国内海洋渔业船舶2017）》的要求增加了一氧化碳、碳氢化合物、颗粒物3个控制项目,氮氧化物的排放限值也明显提高。为获知当前中国主流渔船柴油机排放的技术现状、了解履行新标准的差距,对2种典型的渔船柴油机进行了排放污染物测试试验和劣化试验验证。试验结果显示：典型渔船柴油机可满足新标准一阶段的要求,但距离二阶段要求有较大差距。其中颗粒物的排放超出二阶段限值25%~53%。通过两型柴油机试验数据的对比分析发现,燃油喷射方式是改善颗粒物排放和有效降低柴油机劣化程度的关键因素。针对渔船柴油机如何更好的履行二阶段排放要求给出建议：推迟新标准二阶段生效;鼓励研发新产品,促进先进技术引进;控制实船使用燃油质量,提高渔民的环保意识;加强实船监管力度。 相似文献
7.
基于HSV彩色模型的自然场景下棉花图像分割策略研究 总被引：6，自引：3，他引：3
棉花成熟度和空间位置的识别是采棉机器人研究的关键技术,解决此问题必须对棉花图像进行分割。选取HSV模型中与亮度无关的S通道作为棉花图像的特征,排除了图像明暗变化对分割效果的影响。文中分两种情况对图像信息未缺失的棉花提出了成熟度判别的策略：正面时利用成熟棉花棉瓣的分散性和单朵棉花面积较大等特征进行判别;侧面时通过成熟棉花棉瓣相对棉荚面积比较大的特征进行识别。根据提取分割后棉花图像的几何信息,可确定棉花的重心位置。试验结果表明：该算法能很好地将成熟棉花从背景中分离出来,并较好地保存了棉花的轮廓信息。 相似文献
8.
北京市农产品商品基础信息数据库设计与应用 总被引：1，自引：1，他引：0
农产品商品品种是农产品市场信息的载体,而农产品市场信息是做好农产品市场行情分析、预测、预警的基础。由此可见,开发设计农产品商品基础信息数据库是非常必要的。因此,从总体架构设计、功能模块构建以及数据库应用方面对农产品商品基础信息数据库做了介绍。重点介绍了分类检索模块、形态检索模块、综合检索模块、品种检索模块、名词术语检索模块以及质量分级检索模块的特点及用途,并详细分析了农产品商品数据库在农产品市场信息采集标准、农产品市场行情分析预测以及农产品品种更替等方面的作用。农产品商品数据库的建立不仅为规范农产品市场信息采集标准提供参考,而且可为其他相关行业数据库开发提供借鉴。 相似文献
9.
This article deals with the research on the features and collaborative process of independent development of key automobile parts. It generally employed concurrent engineering theory and technologies of Internet & Intranet, computer aided design (CAD), computer aided manufacturing (CAM) and product data management (PDM). Field knowledge on independent development of key automobile parts was concluded and a set of concurrent collaborative environment and key enabling supporting technologies that face the independent development of automobile body panel dies were also built up. Meanwhile it introduced the secondary development methods of knowledge based engineering (KBE) to implement the knowledge transformation of designing and manufacturing experiences for an enterprise. The results was applied for the development & production of one of this enterprise's new automobile styles and work well. 相似文献
10.
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
11.
Aiming at the urgent requirements of project management from roadway design enterprises, key technologies and application of networked roadway design project management are studied. First, requirements analysis and a general technology scheme are proposed for networked roadway design project management. Next, key technologies are studied systematically, including workflow analysis and improvement, networked and dynamic project monitoring and coordinating, and integrated project information management. Based on the key technologies, an application system of networked roadway design project management is developed and applied in some real projects of roadway engineering design. A case study is presented to illustrate the management process based on the networked project management system. The engineering applications show that the system can effectively improve the management efficiency, reasonably configure and optimize design resource, monitor and coordinate project plan and schedule, and accurately evaluate the performance of design team members. 相似文献
12.
Incomplete information of the poker games make the research progress lags behind the chess games in AI. Although it is still very difficult to find a fast algorithm to solve a poker game with complete information which is the foundation of some advance researches. This paper gives a standard way to encode and store a game state into hash table, so the memory of hash table can be used more effectively and higher hit rate can be gotten in Scout search meth od. With the new encoding method, the total expanding leaf nodes reduces by around 5%. 相似文献
13.
When users try to get Information over the Internet, Information overload has become a serious problem.So we propose to use intelligent information retrieval IIR agents as a solution to this problem.Based on the analysis of the features of retrieval system, including intelligent search, navigation guide, auto-notification, personal information management, dynamic personalized Web pages, and tools for page reading-aide, we discuss the responsibility of each component of intelligent information retrieval agent and how to organize these components to perform various functions to settle above problem, referring to the modularization structure of agent. Intelligent agent is doable and efficacious to increase the efficiency of information retrieval and to lighten network jam by preliminary practice. 相似文献
14.
Knowledge representation is one of the key technologies in the designed expert system.According to the requirement of total design of motorcycle, this paper researches the classificationof knowledgeand experienceof the motorcycle, analyses the points of knowledge representationmethod such as production rule, frameworkand object-oriented and so on, and puts forward the object-oriented knowledge representation method which is combined with abstraction, encapsulationand inheritanceof object-oriented technique. At last the authors realizes the knowledge representation of motorcycle designing under the language environmentof C++ and givesthe knowledge representationexamples of motorcyclebodywork designing. 相似文献
15.
Hongjun Yong Fengyi Zhang Juan Tang Zhiyuan Yang Xinzhe Zhao Mingshun Li Degui Zhang Zhuanfang Hao Jianfeng Weng Xinhai Li 《Euphytica》2018,214(1):1
This review on the resistance to wheat blast disease focus on the latest knowledge useful for the breeders, but also takes into account the lacks in these knowledge. To tackle this disease, it is relevant to apply a breeding strategy which has previously proven its efficacy for obtaining rice varieties with a high level of partial and durable resistance to blast. But, incomplete information is available on wheat blast resistance. Therefore, firstly, it is necessary to adjust this breeding strategy considering the worst hypothesis corresponding to every lack of knowledge. Next, the possible invalidation of every hypothesis can allow simplifying the breeding schema and its implementation. For every lack of knowledge, the practical consequences of the corresponding worst hypothesis, the study of its validity and the consequences of its possible invalidation are explained. Scientific arguments, materials and methods details are provided with the latest available references. 相似文献
16.
In view of the complexity of the measuring environment and uncertainty of the a prior knowledge for rocket aviation,a rocket safety control system based on uncertainty reasoning is proposed.The uncertain representation and processing of the knowledge in expert systems are established according to the characteristics of the parameters .Following the characteristics of the decision rules and decision procudure,the reasoning control strategy is studied and the method for conflict resolving strategy and searching strategy is proposed.Then,the uncertain matching rules and the feasibility degree delivering method are expressed,and the decision-making network and the rule-based uncertainty reseaoning model were constructed.Simulation experiments show that this system can acquire the craft launching information quickly and accurately,which greatly improves the reliability and authenticity of safety control decision for rocket aviation,and can control the rocket aviating state effectively. 相似文献
17.
本文旨在梳理当前应用于中国农业中的绿色防控技术,为中国发展绿色防控技术奠定理论基础,以中国知网数据库作为原始文献来源,高级检索“主题”=“绿色防控”、“并含”=“技术推广”、时间为2010—2019年、采用文献研究法分析所获得344篇文献的相关信息。归纳中国农业现阶段在绿色防控技术应用与推广中存在的问题,并且针对存在的问题提出可供参考的相应解决对策。结果表明：通过分析所发表的文章的数量及分布可以看出,中国绿色防控技术正处于不断发展的阶段,更多的研究者在深入探索这一领域,其中生物防治技术和物理防治技术由于适用性较强,在中国各区域内推广迅速,已经在中国进行广泛应用。 相似文献
18.
In order to optimize disassembly sequence about wornout or malfunctioning products,firstly,it is proposed to build Interference-Freeness Matrix for describing the structure of assembly.Secondly,computing model of automatic generating and optimizing disassembly sequence of assembly is proposed based on Genetic Algorithms.Then,after inputing some disassembly sequences and other controlling parameters,the program can search optimizing disassembly(sequences) valid in geometry.Minimal reorientation number of times during disassembling assembly is assigned as optimizing objective.At last,because the neighborhood may converge too fast and limit the search to a local optimum prematurely during the process of Genetic Algorithms(GAs),the authors combine the strengths of GAs and Tabu search and presented the detailed flow chart of the hybrid approach.More robust search behavior can possibly be obtained by incorporating the(Tabu's) intensification and diversification strategies into GAs.The details of the hybrid approach and a case study are presented here.Much engineering examples is tested to demonstrate the approach.The results given show that the valid disassembly sequences obtained are superior to those derived from GAs alone in fitness value,number and distribution. 相似文献
19.
A vast amount of information data must be input before finite element analysis of steel frames, such as node information, element information and load information. It is necessary to develop a computer aided design system with 3D interactive function. A CAD system for steel frame based on object ARX is developed with AutoCAD API and the Object -oriented technique. In this paper, some key programming technologies is studied, including design of structures, identification of floor system, also, it has presented the relevant implementing code. 相似文献
20.
The GIS function and technique characteristics are introduced. With Client/Server and Browser/Server structure, the paper developed the soil information system based on GIS by using MapInfo to manager spatial data and SQL Server attribute data. The system realizes the inquire, retrieve and statistical analysis of soil fertility and classify information. The function of thematic map making, output and renew are also supported. The system does good to make better use of soil information. 相似文献