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21.
本文应用电力载波技术,实现远端时钟的中央控制。系统通过电力载波芯片从电力线上收发控制信号,中央控制端发送的时钟校准信号到电力线网络,接人网络的远端时钟接收到校准信号后,由微处理器解析数据调整受控端时钟显示,从而实现时钟的中央控制。 相似文献
22.
A direct solution is proposed to an optimal control problem of linear econometric systems with a quadratic welfare loss function when there are linear equality constraints on the control variables. The direct solution proposed here eliminates the problem of non-uniqueness of the optimal solution, which is present when this optimal control problem is solved using the recursive algorithm proposed by Chow,1 Pindyck2 and Tan.3 If a unique solution to the optimal control problem exists, then the direct solution and the recursive solution coincide. 相似文献
23.
颅面部的 CT扫描检查主要包括颅脑面部上、下颌骨、中耳、内耳、鼻窦、眼眍、眼球及颞骨茎突等部位的扫描检查 ,上述部位的扫描检查的位置的摆法 ,层面的厚度、间距 ,扫描时间及螺距等参数的选择及扫描后图像的后处理工作对检查结果的诊断至关重要。上述参数任意一个选择不当及 相似文献
24.
25.
Ann Goetting 《The journal of primary prevention》1994,14(3):169-186
This paper examines delinquency as it relates to family influences. 相似文献
26.
均一吸收体中SPECT重建多解性的探讨 总被引:1,自引:0,他引:1
通过对重建图像噪声特性的分析,间接证明SPECT的解具有多样性。分别用TretiakMetz、Gulberg、富谷武浩等推导的3种等价重建方法和Belini等推导的重建方法,经计算机模拟重建衰减均匀分布的图像,先预置相同的重建图像的空间分辨率,再比较它们的噪声特性。两种方法重建图像的噪声分布:前者近图像边缘时增大,而后者减小,从而间接证明在假定均匀衰减条件下,SPECT的重建有多解性。 相似文献
27.
Paul A.T. Kelly Isobel M. Ritchie Meharpal Sangra Miranda J.A. Cursham Emma M. Dickson Brenda Kelly Fiona P. Neilson M. Jason Reidy Martha C. Stevens 《Brain research》1994,665(2)
Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control. 相似文献
28.
The incidence of Type 1 diabetes is increasing worldwide, imposing enormous public health costs, as well as profoundly affecting individual quality of life. There is evidence that psychological problems are increased in children with diabetes and this morbidity is often associated with poor metabolic control. Specific risk factors for this dual morbidity are emerging from empirical studies. The next challenge is to identify effective interventions for use with children at risk for adverse mental and physical health outcomes. The intervention literature is reviewed. It is noted that most studies have used diabetes-specific, unstandardized interventions in groups of adolescents, with few interventions trialled with younger children. No study has targeted a specific psychological disorder such as behaviour problems or depression, both of which are known to be increased in children with diabetes and for which effective standardized interventions are available. Attention is drawn to methodological limitations in many of the studies conducted to date and suggestions made to reduce these in future interventions attempting to reduce the burden of illness in children with diabetes. 相似文献
29.
目的提高静脉穿刺成功率,减少患儿因反复穿刺造成的痛苦及恐惧,减轻家长因担心穿刺困难而产生的焦虑,提高治疗和抢救的效率。方法详细介绍了QQC活动在提高儿科静脉穿刺成功率的应用,包括找出目前存在的问题,确定目标、采用流程图的方法分析问题存在的原因,制定相应的质量改进方案,并测量实施结果。结果实施QQC活动后静脉穿刺成功率比实施前明显提高。结论有效的QQC活动可以提高静脉穿刺成功率。 相似文献
30.
The Diploma in Clinical Dentistry (Conscious Sedation and Pain Control) of the Faculty of Dentistry, University of Sydney, is the first dedicated programme devoted to this field in Australia. Its development followed a decision by the Dental Board of New South Wales to require a formal qualification from the University of Sydney before dental practitioners could offer sedation and pain management in practice.
The programme is conducted at Westmead Hospital in conjunction with the Department of Anaesthetics, and satisfies the guidelines developed by the Royal Australasian College of Dental Surgeons and the Royal Australasian College of Surgeons.
The course is conducted either over one or two years, with block sessions requiring attendance at Westmead Hospital, together with assignments which are completed outside the block sessions. In this way, a dental practitioner enrolled in the programme is able to continue practice.
The block sessions need not be completed over one year, but must be completed within two years. 相似文献
The programme is conducted at Westmead Hospital in conjunction with the Department of Anaesthetics, and satisfies the guidelines developed by the Royal Australasian College of Dental Surgeons and the Royal Australasian College of Surgeons.
The course is conducted either over one or two years, with block sessions requiring attendance at Westmead Hospital, together with assignments which are completed outside the block sessions. In this way, a dental practitioner enrolled in the programme is able to continue practice.
The block sessions need not be completed over one year, but must be completed within two years. 相似文献