期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
CINRAD-SA/SB发射机故障定位方法 被引量:31
1
作者 潘新民 汤志亚 +4 位作者 柴秀梅 崔炳俭 黄跃青 王全周 多福学 《气象与环境科学》 2010年第3期78-85,共8页
介绍了CINRAD-SA/SB发射机信号流程、同步信号时序关系及关键点波形参数,从故障现象、雷达终端报警信息、面板监控信息分析入手,根据相关信号流程和关键点波形、参数测试,定位发射机故障到可更换单元,总结了速调管附属电源、高频放大链... 介绍了CINRAD-SA/SB发射机信号流程、同步信号时序关系及关键点波形参数,从故障现象、雷达终端报警信息、面板监控信息分析入手,根据相关信号流程和关键点波形、参数测试,定位发射机故障到可更换单元,总结了速调管附属电源、高频放大链、全固态调制器电路故障分析定位技巧,列举了用调压器法、断开负载法、逐级检测法分析定位全固态调制器电路故障的典型个例,并提出了发射机维修方面的一些建议。 展开更多
关键词 全固态 信号流程 故障可更换单元 故障定位 调压器法
下载PDF
Proximal gastric motility in critically ill patients with type 2 diabetes mellitus 被引量:3
2
作者 Nam Q Nguyen Robert J Fraser +2 位作者 Laura K Bryant Marianne Chapman Richard H Holloway 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第2期270-275,共6页
AIM: To investigate the proximal gastric motor response to duodenal nutrients in critically ill patients with longstanding type 2 diabetes mellitus.METHODS: Proximal gastric motility was assessed (using a barostat... AIM: To investigate the proximal gastric motor response to duodenal nutrients in critically ill patients with longstanding type 2 diabetes mellitus.METHODS: Proximal gastric motility was assessed (using a barostat) in 10 critically ill patients with type 2 diabetes mellitus (59±3 years) during two 60-min duodenal infusions of Ensure (1 and 2 kcal/min), in random order, separated by 2h fasting. Data were compared with 15 non-diabetic critically ill patients (48 ± 5 years) and 10 healthy volunteers (28 ±3 years). RESULTS: Baseline proximal gastric volumes were similar between the three groups. In diabetic patients, proximal gastric relaxation during I kcal/min nutrient infusion was similar to non-diabetic patients and healthy controls. In contrast, relaxation during 2 kcal/ min infusion was initially reduced in diabetic patients (P 〈 0.05) but increased to a level similar to healthy humans, unlike non-diabetic patients where relaxation was impaired throughout the infusion. Duodenal nutrient stimulation reduced the fundic wave frequency in a dose-dependent fashion in both the critically ill diabetic patients and healthy subjects, but not in critically ill patients without diabetes. Fundic wave frequency in diabetic patients and healthy subjects was greater than in non-diabetic patients.CONCLUSION: In patients with diabetes mellitus, proximal gastric motility is less disturbed than nondiabetic patients during critical illness, suggesting that these patients may not be at greater risk of delayed gastric emptying. 展开更多
关键词 Proximal gastric function Diabetes mellitus type 2 Critical illness Enteral nutrition
下载PDF
A Parameter Determination Method of Distribution Voltage Regulators Considering Tap Change and Voltage Profile
3
作者 Yuji Hanai Yasuhiro Hayashi +2 位作者 Junya Matsuki Yoshiaki Fuwa Kenjiro Mori 《Journal of Energy and Power Engineering》 2012年第1期117-125,共9页
This paper proposes a parameter determination method of distribution voltage regulators load ratio control transformers (LRT) and step voltage regulators (SVR) considering the tap change and voltage profile. The m... This paper proposes a parameter determination method of distribution voltage regulators load ratio control transformers (LRT) and step voltage regulators (SVR) considering the tap change and voltage profile. The method takes two procedures in order to simplify the optimization problem and to reduce calculation time. One is to simultaneously determine the control parameters of LRT and SVR minimizing voltage violations and voltage variations. The algorithm is based on particle swarm optimization (PSO), which is one of non-linear optimization methods by using a concept of swarm intelligence. Another is to determine the dead-band width of LRT and SVR on the basis of bi-evaluation of tap change and voltage margin. The concept of a Pareto optimal solution is used for the decision of the best dead-band width. As the results of numerical simulations using distribution network model, the validity of the proposed method has been affirmed. 展开更多
关键词 Distribution network voltage control LRT SVR control parameter deadband PSO.
下载PDF
Using the EMD Method to Determine Fault Criterion for Medium-low Pressure Gas Regulators 被引量:11
4
作者 HAO Xuejun LIU Qiang +1 位作者 YANG Guobin DU Yi 《Journal of Thermal Science》 SCIE EI CAS CSCD 2015年第6期557-561,共5页
By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Ev... By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Eventually,the medium-low pressure gas regulator fault criterion can be established. 展开更多
关键词 medium-low pressure gas regulator EMD decomposition fault criterion
原文传递
Advances and New Applications Using the Acousto-Optic Effect in Optical Fibers
5
作者 Alexandre A. P. POHL Roberson A. OLIVEIRA +5 位作者 Ricardo E. DA SILVA Carlos A. F. MARQUES Paulo de Tarso NEVES JR. Kevin COOK John CANNING Rogério N. NOGUEIRA3 《Photonic Sensors》 SCIE EI CAS 2013年第1期1-25,共25页
This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural a... This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural and longitudinal acoustic modes in the frequency range up to 1.2 MHz is highlighted. A combination of the finite elements and the transfer matrix methods is used to simulate the interaction of the waves with Bragg and long period gratings. Results show a very good agreement with experimental data. Recent applications such as the writing of gratings under the acoustic excitation and a novel viscometer sensor based on the acousto-optic mechanism are discussed. 展开更多
关键词 ACOUSTO-OPTICS fiber gratings optical fibers optical sensors
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部