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51.
选择广州某图书馆作为实测对象,从9:00至21:00每隔2 h对图书馆内的空气品质状况进行主、客观实地调查,获得各时段图书馆内的客观指标值及图书馆内人员的空气品质不满意率。利用灰色关联分析方法,计算图书馆内空气品质的客观指标与图书馆内各类人员的空气品质不满意率之间的灰色关联度,以及分析预处理后的客观指标曲线图与空气品质不满意率曲线图关系,最终得出对图书馆内各类人员的空气品质不满意率影响最主要的客观指标是相对湿度、新风量、温度。  相似文献   
52.
一般而言,电子类产品所需的配件种类比较复杂,最终产品的质量竞争力不仅由其生产厂家决定,还受到中间各级供应商所供应配件质量水平的重要影响.本文在介绍企业与供应商传统竞争关系的基础上,重点分析了纵向集成(vertical integration)环境下企业与供应商之间的互利共赢关系,并借助上汽五菱与本田公司两个实例讲述了互利共赢关系下双方提升质量竞争力的一些途径.  相似文献   
53.
SON中基于蚂蚁网络的QoS单播路由机制   总被引:1,自引:0,他引:1       下载免费PDF全文
王兴伟  郭磊  秦培玉  黄敏 《电子学报》2010,38(10):2329-2335
 本文提出一种基于群体智能的自组织网络SON (Self-Organizing Network)中的服务质量QoS (Quality of Service)单播路由机制,通过引入模糊数学相关知识描述不精确路由信息,通过引入微观经济学相关知识兼顾网络提供方和用户利益,基于蚂蚁网络寻找使各方效用达到或接近Nash均衡下Pareto最优的QoS单播路径.基于网络仿真器NS2 (Network Simulator 2)对该机制进行了仿真实现和性能评价,结果表明,该机制在用户效用、网络提供方效用、路径综合评价值、Nash均衡下Pareto最优比和路由成功率等方面具有良好性能.  相似文献   
54.
罗嵘 《现代导航》2014,5(4):282-287
DDS是对象管理组织(OMG)推出的数据分发服务规范,专门针对分布式实时系统中基于数据的发布/订阅架构。本文研究了一种基于DDS模型的信息分发方法,然后通过一个例子演示了这种信息分发方法。该方法可很好的满足某平台系统对于数据传输的高可靠性、高实时性的要求。  相似文献   
55.
56.
《Analytical letters》2012,45(15):2109-2124
Selective and efficient analytical methods for authentication and quality evaluation of herbal medicines are significant and necessary. An expeditious method combining multi-components determination and fingerprinting based on ultra-performance liquid chromatography-photo diode array-tandem mass spectrometry (UPLC-PDA -MS/MS) and chemometrics for authentication and quality evaluation of Cornus Officinalis Sieb. et Zucc was developed. Tandem mass spectrometer operating in multiple reaction monitoring (MRM) was used for determination of three characteristic constituents (morroniside, sweroside, and loganin) in C. Officinalis. Meanwhile, UPLC fingerprint of C. Officinalis was established and the data set was submitted for classification to a suite of chemometrics method. Combing main biologically active components content level and chemometrics analysis, the effects of cultivation area, harvesting, and storage time on the quality of C. Officinalis were investigated. The study reveals that multi-components determination coupled with fingerprinting could be applied for authentication and quality evaluation of C. Officinalis which is accurate, efficient, and reliable.  相似文献   
57.
Many cities all over the world are making large investments for the construction of big network infrastructures, in order to offer to local public organizations, businesses and citizens high speed connectivity, and on top of them useful e-services, aiming to achieve various social and economic objectives. The value generated from these costly ‘digital city’ investments is actually the value provided to the citizens and businesses by the e-services that will be developed and run on these network infrastructures. This paper proposes and validates a structured methodology for assessing and improving e-services developed in digital cities. The proposed methodology assesses the various types of value generated by an e-service, and also the relations among them, allowing a more structured evaluation, a deeper understanding of the value generation process and also identification and prioritization of the improvements that should be made in the e-service with the usually scarce resources in municipalities. This methodology is applied for the evaluation of an e-learning service developed in the Greek city of Karlovassi for young citizens, and also for the prioritization of the necessary improvements in it. The above application provided positive and encouraging evidence concerning the validity, usefulness and applicability of the proposed method.  相似文献   
58.
A method for analyzing the influence of noise on newborns is proposed. The method consists of defining three different types of time interval (quiet, noisy and nursing) and, for each period, environmental noise levels, heart rate, mean arterial pressure and oxygen saturation is continuously measured. The statistical analysis of the influence of the equivalent noise level, rather than instantaneous noise level, on the behavior of the physiological variables is carried out. Great influence of noise is found by using this method, which is also easily translatable to other intensive care units as actual noise conditions are used in the investigation. Moreover, episodes of Bradycardia, Hypoxia and Hypertension are easily related to simultaneous direct nursing activity or a short but high enough noise event, suggesting that both sustained noisy environment and isolated peak noises lead to the alteration of the physiological variables.  相似文献   
59.
根据自己多年的工作经验,从系统的观念来阐述激烈市场竞争中PCB企业应对之道,管理心得。  相似文献   
60.
In recent years, high-energy ultrasound has been used as an alternative to improve the functional properties of various proteins, such as from milk, eggs, soy and poultry. The benefits of implementing this technology depend on the inherent characteristics of the protein source and the intensity and amplitude of the ultrasound, as well as on the pH, temperature, ionic strength, time, and all of the variables that have an effect on the physicochemical properties of proteins. Therefore, it is necessary to establish the optimal conditions for each type of food. The use of ultrasound is a promising technique in food technology with a low impact on the environment, and it has thus become known as a green technology. Therefore, this review focuses on the application of high-energy ultrasound to food; its effects on the functional properties of proteins; and how different conditions such as the frequency, time, amplitude, temperature, and protein concentration affect the functional properties.  相似文献   
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