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61.
The ElectroScan environmental scanning electron microscope (ESEM) enables wet samples to be observed by eliminating air but allowing water vapour into the sample chamber. However, evaporation from, and condensation on, the sample may occur during the pumpdown sequence used to reach this state, which means that the sample may not be in its natural state when viewed if due care is not taken. In this paper, the pumping system of the ESEM is described mathematically and expressions are derived for the evaporation and condensation. This treatment is then used to calculate the optimum pumpdown sequence. The importance of using the optimized procedure is illustrated by micrographs of fat emulsions. 相似文献
62.
A vibration-acoustic method for diagnostics and monitoring of production processes such as cutting metals makes it possible
compared with other methods to reduce the requirement for measuring equipment and it provides a computer representation of
the results observed. The set of equipment suggested has low cost and it exhibits considerable flexibility compared with existing
equipment.
__________
Translated from Izmeritel’naya Tekhnika, No. 7, pp. 30–34, July, 2006. 相似文献
63.
We propose in this paper a self-organized monitoring architecture for mobile ad-hoc networks based on a selective scheme where
subsets of nodes are managed. These nodes are determined based on their network behavior in order to favor subsets of well-connected
nodes. The key idea is to relax the requirements of the management plane, and to use these manageable subsets to monitor the
performance of the overall network. We therefore propose a new performance metric to be monitored, in order to estimate the
capability of ad-hoc nodes to communicate end-to-end in the network. Extensive simulations show how different parameters affect
this metric. 相似文献
64.
Carolyn McGregor Bruce Kneale Mark Tracy 《Journal of Network and Computer Applications》2007,30(4):1309-1323
Premature and ill term babies born in regional Australia must be moved to another hospital with Neonatal Intensive Care Unit (NICU) facilities. Transferred pre-term and critically ill term babies have higher mortality rates and much higher rates of long term disability than similar babies born in hospitals with NICU facilities. This paper details the Bush Babies Broadband project that aims to significantly improve the quality of treatment for babies born in rural, remote as well as urban areas by providing the first on-demand virtual NICU architecture in Australia. Real-time data collected from medical monitors and ventilators attached to the baby, audiovisual streams and static physiological data such as X-ray images are transmitted to the consulting Neonatologist to gain a better picture of the patient's condition than is currently available. The key contribution of this significant research is the infrastructure providing a mechanism for Neonatologists to receive information directly from a regional hospital, thereby preventing, in some cases, the immediate need to move the baby. A key benefit of this framework is that it is available to link regional hospitals with the supporting NICU Neonatologist ‘on demand’ eliminating the need to establish permanent point to point connections. This paper further describes the application of that architecture to a specific pilot connecting the Bathurst regional hospital with Neonatologists within the NICU at Nepean Hospital, Penrith Australia. 相似文献
65.
土壤中的多环芳烃(PAHs)类有机污染物的生物有效性低,不易降解。本文综述了影响污染土壤中多环芳烃降解的环境因素和促进降解措施的研究进展。影响土壤中多环芳烃降解的因素,包括水分、养分、土壤物理条件等;促进土壤中多环芳烃降解的措施有:向污染土壤添加有机溶剂、利用冯顿反应、添加堆肥和有机物料等。从目前研究来看,应当通过促进多环芳烃从土壤上解吸和培育具有较高多环芳烃降解能力的微生物来促进多环芳烃污染土壤的修复。 相似文献
66.
67.
农业重组微生物生物安全研究进展 总被引:2,自引:2,他引:0
综述了近年来农业重组微生物的研究现状和进展 ,详细介绍农业重组微生物环境释放的监控方法以及对环境的冲击作用 ,对一些有关生物安全研究的热点问题进行了探讨 相似文献
68.
映秀湾水力发电总厂计算机监控系统建设较早,因受当时计算机应用技术限制,使得目前运行的计算机监控系统存在很多不足之处,为此,提出对该系统进行改造的设想,旨在能进一步满足映电总厂“无人值班”(少人值守)和安全经济运行的需要。 相似文献
69.
This paper is concerned with (1) an explicit solution of a minimum variance control law for linear time-variant (LTV) processes in the transfer function form, and (2) performance assessment of LTV processes using minimum variance control as the benchmark. It is shown that there exists a time-variant, absolute lower bound of process variance that is achievable under LTV minimum variance control and can be estimated from routine operating data. This lower bound can subsequently be used to assess the benefit of implementing LTV control such as adaptive control. The proposed methods are illustrated through simulated examples and an industrial case study. 相似文献
70.
打括隧道监控量测结果的一元非线性回归分析 总被引:2,自引:0,他引:2
针对黄织铁路工程打括隧道923延米V级围岩土质地段,根据施工中的地质动态对打括隧道初期支护中监控量测结果进行一元非性线回归分析,以制定科学施工方案和确定合理支护参数,保证工程质量和作业的安全性。 相似文献