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1.
介绍了LonWorks的组成及特点,将LonWorks现场部霸权主义地能源数据采集管理网络系统,可以实现能源数据的远程自动采集和处理,并可使系统具有较高的性能价格比  相似文献   

2.
The measurement of distortion product otoacoustic emission (DPOAE) delay using the phase gradient method is discussed. A short f2 sweep paradigm is described. Its merits are discussed and comparisons made with other methods. Using sweeps of less than 4%, consistent and reliable measurements were obtained from 12 normal ears, except for a few isolated measurements. Investigation of these apparent anomalies indicated that the short f2 sweep method was sensitive to the localized effects of narrow distortion product intensity notches and spontaneous emissions. It is possible that middle ear pressure instability or some local change in the cochlea sometimes compounded the situation. The intersubject range (63% of the mean) of DPOAE delay values was greater than the range of values observed due to measurement variability (5.6% of the mean) or intrasubject variability (8.5% of the mean) demonstrating that the method can detect real differences between ears. However, comparison with previous work shows that caution is needed in interpreting these data, as all DPOAE phase methods provide only partial latency values. The physical interpretation depends on both the stimulus sweep used and the origin of DPOAES. Our data shows that f1 sweep derived latency is lower than f2 sweep data by more than 20%. Caution also needs to be exercised when comparing cochlear traveling wave delay, as inferred from electrophysiological data, with that obtained from DPOAE delay measurements.  相似文献   

3.
A half century of gossip research from multiple disciplines is reviewed. Discussed are definitions of the construct: social, evolutionary, and personal functions of the practice; and data collection methods. Though people engage in the practice frequently, there has been relatively little psychological research on gossip. The layperson's understanding of the term is included in, but insufficient to encompass, definitions used by researchers. Most data are ethnographic and discursive, and few parametric data exist. The area could benefit from better experimental methods and instruments. Neurobiological and social network analysis methods are promising foundations for further study. There are real-world implications for understanding gossip. Strengthening gossip theory and research methods will beneficially inform the way we view the practice in context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Clinical vs. statistical prediction is only ? the problem—and the last ? at that. The prior problem, largely neglected, is clinical vs. mechanical measurement—for data can be collected, as well as combined, in either way. Such neglect promotes an incomplete and mismatched dialogue where "clinical" and "statistical" may have different meanings to different persons. Examining clinical and mechanical methods of both measurement and prediction provides a broadened framework that defines the several possible "clinical" and "statistical" methods, and their combinations. Applying this framework to 45 studies shows an apparent superiority for mechanical modes of both data collection and combination, and also suggests that the clinician is more likely to contribute through observation than integration. Grossly uncontrolled differences, however, in clinical training, Ss, criteria, etc., prevent definitive conclusions. To achieve more adequate comparison requires certain specified methodological improvements. (3 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
姜世矫  王立刚  王迷军 《黄金》2011,32(10):38-42
针对矿山企业能源利用不合理、能源数据反馈不及时、能源浪费的现状,设计利用无线传感网络技术建立矿山能耗管理系统,采用ZigBee无线通讯协议,设计无线传感网络节点,组建无线网络,实时传输、采集、存储与分析数据,最终实现能耗评佑与管理,达到节能降耗.  相似文献   

6.
樊飞  吴功平  王满  徐青山  曹琪  杨松 《工程科学学报》2018,40(11):1412-1421
巡线机器人延迟容忍传感器网络(delay tolerant mobile sensor networks for inspection robot,DTMSNR)用于输电线路巡线机器人远程电网数据收集,具有节点稀疏、异构、随机移动性、间歇连通性和延迟容忍性.针对传统传感器网络数据传输算法机器人数据传输成功率低与网络可靠性差等问题.提出一种基于巡线机器人位姿信息的数据传输(mobile robot position-based delivery,MPD)策略.为准确计算巡线机器人网络位姿信息,建立机器人路径约束随机运动模型.MPD采用机器人相对网络位姿信息计算传输概率,进行消息传输路径选择.对网络异构消息引入机器人消息优先传输、消息失效机制进行消息队列管理.仿真实验表明,相较现有的几种延迟容忍传感器网络(delay tolerant mobile sensor network,DTMSN)数据传输策略,针对巡线机器人网络MPD能在适当的传输能耗下达到更高的传输成功率与更低的传输延迟.   相似文献   

7.
The current practice for monitoring of subsurface plumes involves the collection of water samples from sparsely distributed monitoring wells and laboratory analysis to determine chemical concentrations. In most field situations, cost and time constraints limit the number of samples that could be collected and analyzed for continuous monitoring of large, transient plumes. With the development of wireless sensor networks (WSNs), that allow sensors to be incorporated into a distributed wireless communication and processing system, the potential exists to develop new, efficient, economical, large-scale subsurface data collection and monitoring methods. This paper presents a proof-of-concept study conducted in a two-dimensional synthetic aquifer constructed in an intermediate scale test tank to demonstrate the feasibility of using WSN for subsurface plume monitoring. The tank was packed to represent a heterogeneous aquifer, and a sodium bromide tracer was used to create a plume. A set of ten wireless sensor nodes (motes) equipped with conductivity probes to measure electrical conductivity formed the network. Software for automated data acquisition was developed and tested. Results of two experiments conducted using this test system are presented. The lessons learned from the first experiment were used to make modifications to the way the sensors were placed, how they were calibrated and how the sensors were interfaced with the data acquisition system. The findings are used to identify future research directions and issues that need to be addressed before field implementations of a WSN based data collection system for plume monitoring.  相似文献   

8.
We present a mathematical analysis of the piriform cortex activity in rats. Experimental data were obtained by means of optical recording of fluorescent signals driven by neuronal activity. From these data, we determined the numerical value of the relaxation time for the pyramidal cell activity in layers II and III and the time latency map for bulb activation. Our model for the piriform cortex is based on pairs of excitatory and inhibitory neurons which correspond to pyramidal cells of layers II and III and to their inhibitory associated interneurons respectively; pyramidal cells are also interconnected through short and long range association fiber systems. Under such conditions, the model outputs resemble closely the experimental observations: (1) a double-bumped response to a strong and short stimulation; (2) oscillatory behavior under weak sustained stimulation conditions; (3) propagation of traveling activity waves; and (4) pacemaker activity when clusters of neurons are preferentially coupled.  相似文献   

9.
Although it is agreed that there is a need for clinical pathway variance analysis, methods for creating a system are less well defined. To help others down this path, we have developed a list of questions around four core issues: data collection, data entry and analysis, data reporting, and organizational support. Our goal is to identify key questions related to variance management and provide a framework for clinical pathway variance analysis.  相似文献   

10.
多传感器数据融合技术(上)   总被引:18,自引:0,他引:18  
多传感器数据融合技术是近几年发展起来的一门新兴技术,在军事和工业中有着广阔的应用前景。本文论述了多传感器融合的基本工作原理、数据融合结构和功能模型、数据融合方法和应用领域,给出了多传感器数据融合在汽车无人驾驶系统中的应用实例, 总结了当前数据融合研究中存在的问题和研究方向。  相似文献   

11.
Molecular methods are increasingly used to identify microbes in clinical samples. A common technical problem with PCR is failed amplification due to the presence of PCR inhibitors. Initial attempts at amplification of the bacterial 16S rRNA gene from inoculated blood culture media failed for this reason. The inhibitor persisted, despite numerous attempts to purify the DNA, and was identified as sodium polyanetholesulfonate (SPS), a common additive to blood culture media. Like DNA, SPS is a high-molecular-weight polyanion that is soluble in water but insoluble in alcohol. Accordingly, SPS tends to copurify with DNA. An extraction method was designed for purification of DNA from blood culture media and removal of SPS. Blood culture media containing human blood and spiked with Escherichia coli was subjected to an organic extraction procedure with benzyl alcohol, and removal of SPS was documented spectrophotometrically. Successful amplification of the extracted E. coli 16S rRNA gene was achieved by adding 5 microliter of undiluted processed sample DNA to a 50-microliter PCR mixture. When using other purification methods, the inhibitory effect of SPS could be overcome only by dilution of these samples. By our extraction technique, even uninoculated blood culture media were found to contain bacterial DNA when they were subjected to broad-range 16S rRNA gene consensus PCR. We conclude that the blood culture additive SPS is a potent inhibitor of PCR, is resistant to removal by traditional DNA purification methods, but can be removed by a benzyl alcohol extraction protocol that results in improved PCR performance.  相似文献   

12.
This paper presents a novel systems approach to compressing sensor network data. Unlike previous data compression methods, the proposed lossless linear predictor-based sensor data compression method utilizes structural system information to minimize the signal correlation in sensor network data. In the proposed method, linear predictor is derived in a system identification framework in which auto-regressive (AR) model is used as its model structure and the instrumental variables (IV) method is used to calculate the predictor parameters. A parametric study was carried out to study the effects of changes in system property, number of sensors, and sensor noise level on the compression performance of the proposed method. Both numerical simulation and experimental results show that the proposed sensor data compression method has a better compression performance than conventional linear predictor-based data compression method for single sensor.  相似文献   

13.
Objective: The present study tested the hypothesis that social problem solving (SPS) served to mediate the relationship between preceived stress and noncardiac chest pain (NCCP). Design: Adults undergoing stress myocardial perfusion imaging (MPI) to determine the presence of underlying cardiovascular disease related to the experience of chest pain were recruited prior to stress testing to complete a series of self-report inventories. Main Outcome Measures: MPI results were used to identify individuals with NCCP (N = 166; 91 men, 75 women; mean age = 53.92 years, SD = 11.98). Measures included perceived stress, SPS, and chest pain frequency and intensity. Results: In direct tests of the mediational effects of SPS, it was found that two problem-solving dimensions, negative problem orientation and rational problem solving, each served as significant mediators of the effects of stress on both NCCP intensity and frequency. Conclusion: These results support a mediational analysis of NCCP that includes stress and SPS. As such, it identifies SPS as a potentially important clinical target to consider when developing future psychosocial-based therapy protocols for treating individuals with NCCP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Pattern-contingent color aftereffects, or McCollough effects (MEs), are used to probe the visual brain's operations psychophysically. Their neural substrate is unknown, however, and theories about them are weak. Our theory proposes a strong functional role for MEs and a neuropsychological basis that accounts for "top-down" (global) constraints ignored by other theories. The functional aspect of the theory is based on the concept of contingent adaptation level, following H. Helson (1964), and on the "error-correcting device" of D. P. Andrews (1964), which tracks and adjusts internal representation to external-world contingencies. The neuropsychological part of the theory postulates that global properties are the result of MEs being generated not at the individual detector level but in the vectorfields of which the detectors are elements. It is an implementation of Lie transformation group theory (W. C. Hoffman, 1966). Evidence for this model is assessed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Objective: To enhance understanding of the role that social problem solving (SPS) plays in community integration following traumatic brain injury (TBI). Study Design: Regression analysis. Participants: Forty-five adults with TBI participating in higher level outpatient cognitive rehabilitation and 15 uninjured adults. Main Outcome Measures: Measures of community integration, problem-solving ability, and SPS self-appraisal and performance. Results: Individuals with TBI demonstrated poorer problem-solving as measured by both neuropsychological and SPS methods; however, the largest effect' size was observed for SPS self-appraisal. Only SPS self-appraisal predicted a significant proportion of the variance in community integration. Conclusions: It is important to assess brain-injured persons' confidence in their ability to cope with problems. A focus on objective test scores alone may lead to underdetection of disabling problem-solving deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
McCollough effects (MEs), first described by C. McCollough (1965), are perceptual aftereffects of color that depend on the spatial configuration of line patterns. Several investigators have suggested that MEs may be the product of an associative learning mechanism, and G. M. Murch (see record 1976-20108-001) developed a formal model attributing MEs to classical conditioning. In the present article, Murch's conception is evaluated by comparing the basic characteristics of conditioning with those of MEs. Although some similarities are noted, MEs differ from CRs in that they fail to display relative permanence, be disrupted by reduction of the correlation between the CS and UCS during acquisition, and show accumulative effects of practice. It is concluded that MEs are not classically conditioned responses; the question of whether they can be regarded as any form of learned behavior is debated. (74 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
18.
The randomized controlled clinical trial (RCT) is a prospective study using random assignment of subjects to treatment groups to compare the effect and value of a therapeutic intervention against a control. The RCT is the most definitive clinical research tool for evaluating the efficacy of a new therapy in human subjects. Often the outcome of interest in an RCT is the length of time until an event occurs after treatment or intervention. In this article we introduce statistical methods for evaluating differences in the patterns of time to response between two groups of subjects to determine whether one therapy is better than another. The collection of methods for analyzing such data, known as survival data, is called survival analysis. Using data from a hypothetical clinical trial for the prevention of the recurrence of depression, we illustrate two elementary methods for analyzing survival data. We also discuss generalizations of these methods to incorporate covariates and conclude with a general discussion of clinical trials of psychiatric therapies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
钌金属溅射靶材烧结工艺研究   总被引:1,自引:0,他引:1  
采用热压、放电等离子烧结及直接热压等粉末冶金工艺制备了钌金属溅射靶材,通过对致密度、晶粒度与氧含量分析研究了工艺过程对钌金属靶材制备的影响,并对比分析了三种方法制备钌靶的特点。结果表明:通过工艺优化利用三种方法均能制备出相对密度达到99%以上的高密度钌靶;随着制备温度的升高,钌靶氧含量降低,晶粒尺寸增大;热压工艺制备周期最长,钌靶表面有晶粒粗大层;放电等离子烧结与直接热压工艺都具有快速、近净成形的特点。  相似文献   

20.
针对钢铁企业的热轧批量计划编制问题,考虑了热轧生产工艺规程、同宽板坯连轧长度限制等约束,建立基于不确定旅行商数的多旅行商问题(MTSP)的热轧批量计划数学模型,把轧制单元计划数最小化和紧邻轧制板坯间轧制宽度、厚度、硬度差异而造成的总惩罚值最小化作为优化目标。结合模型的实际情况,采用基于两交换启发式的改进遗传算法对问题进行求解。最后,利用某钢厂的实际生产数据进行计算试验,同时对结合传统遗传算法和改进遗传算法的优化情况进行对比和结果分析,模型的正确性和算法的有效性得到了验证。  相似文献   

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