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101.
移动代理(M0bile Agent)是一种新型的分布式计算技术,它本身又具有移动性,智能性,并行性等特点,为建立网络多媒体信息服务系统提供了一种崭新的思路.提出基于移动代理技术的网络多媒体信息服务系统的体系结构并指出其关键技术与研究方向.  相似文献   
102.
目前,GIS技术已经广泛地应用于各行各业,组件式软件技术广泛应用于软件和系统开发,组件式GIS是未来GIS发展的重要趋势.主要介绍组件式软件开发原理,相关技术,以及当前组件式GIS 设计中最常用的MapObjects控件;阐述在VB 环境下利用MapObjects开发组件式GIS软件的方法.详细介绍应用此方法开发北京市信息服务系统的过程,主要包括系统的总体设计分析、模块分析、系统结构和功能设计等.该系统的主要功能有:地图的放大、缩小和移动等,地物的查询以及信息的查询和服务等.  相似文献   
103.
基于元数据的交通科学数据共享平台的设计与实现   总被引:1,自引:0,他引:1  
针对由于交通科学数据分散、孤立、垄断以及存储方式各异等造成的已有交通科学数据利用率低、不能充分为社会、科研和教学服务等问题,采用图书标引和编目的思想,基于元数据和Web Service等计算机技术,初步构建交通科学数据共享平台的方案,实现交通科学数据共享和整合,以提高交通科学数据利用率和服务能力.  相似文献   
104.
在实际项目开发过程中,结合.NET瘦客户端的小巧性和J2EE技术在安全性及事务控制上的优点,选择用Web Service技术进行.NET的瘦客户端和基于J2EE标准的WebLogic的服务器端的协同开发.将阐述的是上述开发过程中所遇到的WebLogic和.NET协同开发Web Service过程中的安全问题解决方法.  相似文献   
105.
This study reviews the literature on air cargo operations and compares theoretical studies with the practical problems of airlines, freight forwarders, and terminal service providers. In particular, we review studies in which mathematical models were used to identify the essential characteristics of air cargo operations, such as the intrinsic differences from passenger operations, and to explore the service processes in air cargo operations. The typical models used in previous studies are summarized. We then highlight the insightful findings from an industrial interview and present the gaps between previous research and practical realities. We finally discuss the new research opportunities of air cargo operations according to the gaps.  相似文献   
106.
Road traffic accidents (RTA) are a prevalent cause of fatality with African countries having the highest fatality index (25–34 per quota). The World Health Organization estimates Kenya's fatality rate due to RTA at 28 per quota. From literature, the country's fatality and injuries have increased by 26% and 46.5%, respectively, since the year 2015. The country is faced with incomplete RTA data capturing, hindering effective planning and policy adjustments to curb the menace. In this paper, we scrapped user-generated data (Twitter) and national transport and safety authority's (NTSA) reports to shed light on traffic safety, practices, and cultures in the country. To this end, we gathered 1,000,000 tweets and 8000 speeding entries between 2015 and 2021 and performed natural language processing (NLP) and quantitative study of the data. We applied NLP and n-gram search of keywords to categorize data into 8 topics: traffic, public service vehicle (PSVs), policing, accident, infrastructure, recklessness, robbery, and corruption. From the data, policing, which touches on all police and law-enforcement-related activity was found to be highly correlated with PSVs, recklessness, accidents, traffic congestion, robbery, infrastructure, and corruption with indices of r(76) = 0.92, 0. 91, 0.87, 0.82, 0.81, 0.76, and 0.70, respectively with p < 0.001. The topic modeling confirmed the identified topics to be the latent discussion issues affecting the public. From the study, PSVs, policing and traffic flow were isolated as key issues that ought to be addressed immediately. The research recommended the integration of driver monitoring systems to strengthen policing. The research, which utilized unstructured data, points to the utility of data mining which would greatly benefit traffic research, particularly African-based studies, that suffer from data inadequacy.  相似文献   
107.
The measurement of transit service quality is very important for guaranteeing a transport supply characterized by satisfactory service levels for the passengers. Even more important is the monitoring of the levels of service quality over time, which can be very useful to determine if the goals established by the transport planners are being met or exceeded. The status and evolution of transit service quality can be monitored through periodic and regular updating of the opinions expressed by the passengers about the service during the well-known Customer Satisfaction Surveys, allowing the effect of policies to be evaluated and specific interventions to be introduced. In this work, just the issue of monitoring service quality based on users’ opinions is approached, and the index numbers usually applied in the economic and industrial field are proposed for this purpose. Index numbers permit to study the fluctuations or variations of a variable or more variables over time, providing a powerful measurement for making comparisons and predictions of the analyzed concept. The index numbers were calculated on the basis of data collected from Customer Satisfaction Surveys addressed to the passengers of the metropolitan public service of Granada (Spain). The analyzed time period has been established from 2007 to 2013. Interesting results derive from the calculation of the index numbers. Since both perceptions and importance rates are considered in this methodology, the results can inform, not only on the satisfaction tendencies but also on the trend on customers’ priorities, which is actually the expected quality. Therefore, policies could more efficiently be designed to adjust the service to the users’ real needs.  相似文献   
108.
介绍了单片机控制技术、三相脉宽调制技术、可靠性设计技术、轴承净化技术和降噪技术在电控罗经设计中的应用,这对提高国产船用电控罗经性能具有重要的参考价值。  相似文献   
109.
社会主义新农村建设是一项系统工程,一个有机联动的架构。通过对架构的解析,论证经济发展是新农村建设整个架构的核心,生态环境架构、社会文化组织架构、制度环境架构是经济发展架构得以顺利实现的保障。社会主义新农村建设重点在于寻求以经济发展为核心的各架构搭配的黄金分割点。  相似文献   
110.
网络的 QoS(Quality of service)决定用户对网络提供业务的满意程度,良好的 QoS 管理是网络成功的关键。本文详细分析了分组网络中广泛应用的 IEEE802.1d 协议的 QoS 机制、IETF(Internet Engineering Task Force) 为 Internet 制定的 QoS 机制以及 ATM 论坛的 ATM QoS 机制。在对上述分析基础上,对各种 QoS 机制进行了多维的比较,指出不同 QoS 机制各自的局限性。文章最后对 QoS 管理策略的进一步发展进行了展望。  相似文献   
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