Sample records for real-time myocardial contrast

  1. Evaluation of Myocardial Viability after Myocardial Infarction with Intravenous Real-time Myocardial Contrast Echocardiography

    Weihui SHENTU; Yuhan WU; Youbin DENG; Runqing HUANG; Peng LI; Xiang WEI; Haoyi YANG; Yun ZHANG; Li XIONG; Fen YU


    The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Viable myocardium was defined by evident improvement of segmental wall motion 3 months after coronary revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification; partial or reduced opaciflcation or subendocardial contrast defect; contrast defect. The former two conditions were used as the standard to define the viable myocardium. The results showed that 109 abnormal wall motion segments were detected among 18 patients with myocardial infarction, including 47 segments of hypokinesis, 56 segments of akinesis and 6 segments of dyskinesis. The wall motion of 2 segments with hypokinesis before coronary revascularization which showed homogeneous opacification, 14 of 24 segments with hypokinese and 20 of 24 segments with akinese before coronary revascularization which showed partial or reduced opaciflcation or subendocardial contrast defect was improved 3 months after coronary revascularization. In our study, the sensitivity and specificity of evaluation of myocardial viability after myocardial infarction by intravenous real-time myocardial contrast echocardiography were 94.7% and 78.9%, respectively. It was concluded that intravenous real-time myocardial contrast echocardiography could accurately evaluate myocardial viability after myocardial infarction.


    Lei Zhuang; Ming-xing Xie; Wei-juan Wang; Xiang-xin Yang; Tao Liu


    Objective To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3 DE).Methods RT3DE was performed in 21 open-chest mongrel dogs undergoing acute ligation of the left anterior descending artery (LAD,n=14) or distal branch of the left circumflex artery (LCX,n=7).A perfluorocarbon microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with Philips Sonos7500 ultrasound system. Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. In vitro anatomic measurement of myocardial mass after removal of the animal's heart was regarded as the control. Blinded off-line calculation of left ventricular mass and perfusion defect mass from RT3DE images were performed using an interactive aided-manual tracing technique.Results Total left ventricular (LV) myocardial mass ranged from 38. 9 to78.5 (mean±SD: 60.0±10.1)g. The mass of perfusion defect ranged from 0 to 21.4 (mean±SD: 12.0±5.0) g or 0 to 27% of total LV mass (mean±SD: 19%±6%). The RT3DE estimation of total LV mass (mean±SD: 59.8±9.9 g) strongly correlated with the anatomic measurement (r=0.98; y=2.01+0.96x). The CE-RT3DE calculation of the mass of underperfused myocardium (mean±SD: 12.3±5.3 g) also strongly correlated with the anatomic measurement (r=0.96; y=0.10+1.04x) and when expressed as percentage of total LV mass (r=0.95; y=-0.20+1.04x).Conclusions RT3DE with myocardial contrast opacification could accurately estimate underperfused myocardial mass in dogs of acute coronary occlusion and would play an important role in quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.

  3. Real-time three-dimensional myocardial contrast echocardiography in assessment of myocardial perfusion defects

    CHEN Li-xin 陈立新; YANG Ying 杨颖; FEI Hong-wen 费洪文; WANG Liang-yu 王良玉; WANG Xin-fang 王新房; Navin C Nanda; Andrew P Miller; XIE Ming-xing 谢明星; ZHUANG Lei 庄磊; YANG Ya 杨娅; WANG Jing 王静; HUANG Run-qing 黄润青


    Background Both real-time three-dimensional echocardiography (RT3DE) and myocardial contrast echocardiography (MCE) are novel imaging techniques. The purpose of this study was to confirm the feasibility and accuracy of RT3DE combined with MCE for quantitative evaluation of myocardial perfusion defects.Methods Thirteen dogs underwent ligation of the left anterior descending artery (LAD, n=6) or distal branch of the left circumflex artery (LCX, n=7) under general anaesthesia. Three to four ml of a perfluoropropane (C3F8) microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with a commercially available Philips SONOS-7500 ultrasound system. After removal of the dog hearts, Evans blue dye was injected via the left and right coronary arteries to stain the myocardium at risk. In vitro anatomic measurements of myocardial mass after removal of the animals' hearts were used as controls.Results Left ventricular (LV) mass determined by RT3DE ranged 36.7-68.9 g [mean, (54.6±9.6) g] before coronary artery ligation, and correlated highly (r=0.99) with in vitro measurement of LV mass [range, 38.9-71.1 g; mean, (55.6±9.3) g]. There was no significant difference between RT3DE and in vitro measurements of LV mass [range, 36.7-68.9 g; mean, (51.3±12.5) g. Or range, 38.9-71.1 g; mean, (53.7±12.3) g, respectively] and under-perfused mass [range, 0-21.4 g; mean, (12.0±6.9) g. Or range, 0-19.8 g; mean, (10.8±6.3) g, respectively] after the LAD ligation (P>0.05). Likewise, no significant difference was present between RT3DE and in vitro measurements of LV mass [range, 50.1-65.4 g; mean, (57.5±5.9) g. Or range, 51.5-65.8 g; mean, (57.3±6.4) g, respectively] and under-perfused mass [range, 0-25.6 g; mean, (13.3±9.6) g. Or range, 0-22.7 g; mean, (12.8±8.1) g, respectively] after the LCX ligation (P>0.05). For all the animals with coronary ligation, LV mass measured by RT3DE ranged 35.9-68.6 g [mean, (54.8±10.0) g] and there was

  4. Real-time myocardial contrast echocardiography in rat: infusion versus bolus administration.

    Su, Hai-Li; Qian, Yun-Qiu; Wei, Zhang-Rui; He, Jian-Guo; Li, Guo-Quan; Zhang, Jun; Zhou, Xiao-Dong; Jing, Wang


    To compare the feasibility of real-time myocardial contrast echocardiography (MCE) in rats with infusion and bolus administration of a second-generation ultrasound contrast agent BR1. B-mode real-time MCE was performed in 12 Sprague Dawley rats following the BR1 infusion or bolus injection. The myocardium signal intensity (SI) was plotted against time and was fitted to exponential functions. The plateau SI (A) and rate of SI increase (beta) for the infusion study and peak signal intensity (PSI) for the bolus study were obtained. (99m)Tc-Sestamibi and Evans blue were used to assess myocardial blood perfusion and to calculate the myocardium perfusion defect area ex vivo. High-quality real-time MCE images were successfully obtained using each method. At baseline, all LV segments showed even contrast distribution. Following left anterior descending coronary artery (LAD) ligation, significant perfusion defect was observed in LAD beds with a significantly decreased A* beta and PSI values compared with LCx beds (Infusion: A*beta (LAD): 5.42 +/- 1.57 dB, A*beta (LCx): 46.52 +/- 5.32 dB, p rats and the infusion method was more suitable for quantitative analysis of myocardial blood flow.

  5. Value of adenosine infusion for infarct size determination using real-time myocardial contrast echocardiography

    da Luz Protásio


    Full Text Available Abstract Background Myocardial contrast echocardiography has been used for determination of infarct size (IS in experimental models. However, with intermittent harmonic imaging, IS seems to be underestimated immediately after reperfusion due to areas with preserved, yet dysfunctional, microvasculature. The use of exogenous vasodilators showed to be useful to unmask these infarcted areas with depressed coronary flow reserve. This study was undertaken to assess the value of adenosine for IS determination in an open-chest canine model of coronary occlusion and reperfusion, using real-time myocardial contrast echocardiography (RTMCE. Methods Nine dogs underwent 180 minutes of coronary occlusion followed by reperfusion. PESDA (Perfluorocarbon-Exposed Sonicated Dextrose Albumin was used as contrast agent. IS was determined by RTMCE before and during adenosine infusion at a rate of 140 mcg·Kg-1·min-1. Post-mortem necrotic area was determined by triphenyl-tetrazolium chloride (TTC staining. Results IS determined by RTMCE was 1.98 ± 1.30 cm2 and increased to 2.58 ± 1.53 cm2 during adenosine infusion (p = 0.004, with good correlation between measurements (r = 0.91; p 2 and showed no significant difference with IS determined by RTMCE before or during hyperemia. A slight better correlation between RTMCE and TTC measurements was observed during adenosine (r = 0.99; p Conclusion RTMCE can accurately determine IS in immediate period after acute myocardial infarction. Adenosine infusion results in a slight better detection of actual size of myocardial damage.

  6. Real-time myocardial contrast echocardiography and its applications in evaluation for coronary artery disease



    It is important to assess myocardial perfusion in the diagnosis, treatment and risk stratification of patients with coronary artery disease. At present, single-photon emission computed tomography (SPECT) is used to evaluate myocardial perfusion, but it is limited by relatively low spatial resolution, the need to inject radioisotopes, and not being able to be performed at the patient ' s bedside. Using intracoronary injection of ultrasound contrast agent, the potential of myocardial contrast echocardiography (MCE) instead of perfusion assessment has been proved in numerous animal and human studies. Recent improvements in contrast agents have resulted in stable microbubbles that, following intravenous administration, traverse the pulmonary circulation and reach the left heart. Combined with the emergence of contrast-specific imaging modalities along with quantitative analytical method, intravenous MCE is now a feasible and promising noninvasive technique for perfusion assessment.

  7. Quantification of resting myocardial blood flow velocity in normal humans using real-time contrast echocardiography. A feasibility study

    Slordahl Stig


    Full Text Available Abstract Background Real-time myocardial contrast echocardiography (MCE is a novel method for assessing myocardial perfusion. The aim of this study was to evaluate the feasibility of a very low-power real-time MCE for quantification of regional resting myocardial blood flow (MBF velocity in normal human myocardium. Methods Twenty study subjects with normal left ventricular (LV wall motion and normal coronary arteries, underwent low-power real-time MCE based on color-coded pulse inversion Doppler. Standard apical LV views were acquired during constant IV. infusion of SonoVue®. Following transient microbubble destruction, the contrast replenishment rate (β, reflecting MBF velocity, was derived by plotting signal intensity vs. time and fitting data to the exponential function; y (t =A (1-e-β(t-t0 + C. Results Quantification was feasible in 82%, 49% and 63% of four-chamber, two-chamber and apical long-axis view segments, respectively. The LAD (left anterior descending artery and RCA (right coronary artery territories could potentially be evaluated in most, but contrast detection in the LCx (left circumflex artery bed was poor. Depending on localisation and which frames to be analysed, mean values of were 0.21–0.69 s-1, with higher values in medial than lateral, and in basal compared to apical regions of scan plane (p = 0.03 and p Conclusion Low-power real-time MCE did have the potential to give contrast enhancement for quantification of resting regional MBF velocity. However, the technique is difficult and subjected to several limitations. Significant variability in β suggests that this parameter is best suited for with-in patient changes, comparing values of stress studies to baseline.

  8. Bioeffects of albumin-encapsulated microbubbles and real-time myocardial contrast echocardiography in an experimental canine model

    P.M.M. Dourado


    Full Text Available Myocardial contrast echocardiography has been used for assessing myocardial perfusion. Some concerns regarding its safety still remain, mainly regarding the induction of microvascular alterations. We sought to determine the bioeffects of microbubbles and real-time myocardial contrast echocardiography (RTMCE in a closed-chest canine model. Eighteen mongrel dogs were randomly assigned to two groups. Nine were submitted to continuous intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin (PESDA plus continuous imaging using power pulse inversion RTMCE for 180 min, associated with manually deflagrated high-mechanical index impulses. The control group consisted of 3 dogs submitted to continuous imaging using RTMCE without PESDA, 3 dogs received PESDA alone, and 3 dogs were sham-operated. Hemodynamics and cardiac rhythm were monitored continuously. Histological analysis was performed on cardiac and pulmonary tissues. No hemodynamic changes or cardiac arrhythmias were observed in any group. Normal left ventricular ejection fraction and myocardial perfusion were maintained throughout the protocol. Frequency of mild and focal microhemorrhage areas in myocardial and pulmonary tissue was similar in PESDA plus RTMCE and control groups. The percentages of positive microscopical fields in the myocardium were 0.4 and 0.7% (P = NS in the PESDA plus RTMCE and control groups, respectively, and in the lungs they were 2.1 and 1.1%, respectively (P = NS. In this canine model, myocardial perfusion imaging obtained with PESDA and RTMCE was safe, with no alteration in cardiac rhythm or left ventricular function. Mild and focal myocardial and pulmonary microhemorrhages were observed in both groups, and may be attributed to surgical tissue manipulation.

  9. Estimation of coronary artery stenosis by low-dose adenosine stress real-time myocardial contrast echocardiography: a quantitative study

    ZHOU Xiao; ZHI Guang; XU Yong; WANG Jing; YAN Guo-hui


    Background Coronary microcirculation reserve is an important field in the research of coronary artery disease,but it is difficult to identify clinically.Currently it is widely accepted that myocardial contrast echocardiography (MCE) is a safe,inexpensive method and has comparatively high image resolution.The present study used quantitative low-dose adenosine stress real-time (RT)-MCE to estimate myocardial perfusion and the coronary stenosis.Methods Forty-nine left ventricular (LV) segments from 14 unselected patients were divided into three groups according to the coronary angiography or CT angiography results:group 1 (n=20,41%) without significant stenosis (<70%),group 2 (n=12,24%)with successful percutaneous coronary intervention (PCI),and group 3 (n=17,35%)with significant stenosis (>70%).RT-MCE was performed in these patients with low-dose adenosine stress and continuous infusion of Sonovue.The replenishing curves were drawn according to the contrast density measured at the end-diastolic frame of every cardiac circle by ACQ software.Results Forty-nine LV segments with satisfactory image quality were picked for quantitative contrast echo analysis.The replenishing curves were analyzed at baseline and after stress.Perfusion of group 3 did not decrease significantly at baseline,and showed no improvement during adenosine stress and was significantly different from groups 1 and 2 (P <0.05).The A·β and β increased more significantly in group 1 than in groups 2 and 3 (P <0.05).In a receiver operating characteristic (ROC) curve analysis,A·β under adenosine stress <1.74 dB/s had a sensitivity and specificity of 71% for diagnosis of coronary artery stenosis,reduced adenosine-induced rise (percentage of A·β <81%) had a sensitivity and specificity of 83% and 79% for the diagnosis of low-reserve,and β <54% had a sensitivity of 86% and specificity of 79%.Conclusions Rest perfusion of severely stenosed arteries may be normal

  10. Comparison of the veracity of real-time perfusion, harmonic angio, and ultraharmonic myocardial contrast imaging modes in evaluation of acute myocardial infarction area


    Background Innovative advancements in ultrasound instrumentation present a number of imaging modalities for myocardial contrast echocardiography (MCE) in ischemic syndromes. How well they compare to each other in diagnostic accuracy in the detection of acute myocardial infarction is unclear. The purpose of this study was to assess the relative accuracy of 3 different imaging modes of MCE, low mechanical index (MI) real-time perfusion imaging (RTPI), triggered harmonic angio mode (HA), and ultraharmonic imaging mode (UH) in the detection of acute experimental myocardial infarction within the time frame suitable for potential reperfusion. Methods MCE was performed in 10 open-chest dogs using RTPI, triggered HA and triggered UH modes at baseline and one hour after occlusion of left anterior descending coronary artery. Presence or absence of perfusion defects, and the perfusion defect size when present, were analyzed and compared with the infarct size delineated by triphenyltetrazolium chloride(TTC)staining. Results The infarct area was (15.8±2.4)% by TTC staining; Perfusion defect area by MCE was similar to anatomic infarct area in all the three MCE approaches: (16.1±2.7)% by RTPI mode, (15.5±2.9)% by HA mode, and (15.5±3.0)% by UH mode. The sensitivity, specificity and overall diagnostic accuracy in the detection of myocardial infarction were 100%, 88%, and 94% for RTPI mode, 88%, 100%, and 94 % for HA mode, and 100%, 75%, and 88% for UH mode. Conclusion All modes of MCE, RTPI, triggered HA mode and triggered UH mode have excellent diagnostic accuracy in the immediate hour of acute coronary occlusion within the optimal time frame suitable for reperfusion therapy.

  11. Real-time myocardial contrast echocardiography can predict functional recovery and left ventricular remodeling after revascularization in patients with ischemic heart disease

    ZENG Xin; SHU Xian-hong; PAN Cui-zhen; LI Qing; GUO Shi-zun; LIU Shi-zhen; CHEN Hao-zhu


    Background Previous studies showed that preservation of microvascular integrity after myocardial ischemia was associated with myocardial viability. Real-time myocardial contrast echocardiography (RT-MCE) is a promising modality for non-invasive evaluation of microcirculation perfusion. Thus, it provides a unique tool to detect myocardial viability. We sought in this study to investigate the role of RT-MCE in predicting left ventricular (LV) functional recovery and remodeling after revascularization in patients with ischemic heart disease.Methods Thirty-one patients with ischemic heart disease and resting regional LV dysfunction were included. LV volume,global and regional function were evaluated by echocardiography before and 6-9 months after revascularization.RT-MCE was performed before revascularization using low mechanical index power modulation imaging. Myocardial contrast opacification of dysfunctional segments was scored on a 3-point scale and mean contrast score in dysfunctional segments was calculated. Patients were divided into 2 groups according to mean contrast score in dysfunctional segments: group A, patients with mean contrast score ≥0.5 (n=19); group B, patients with mean contrast score < 0.5(n=12).Results Wall motion improvement was found to be 94.5%, 45.5% and 16.1% respectively (P<0.01) in homogenous,patchy and absent contrast opacification segments. At baseline, there was no significant difference in LV volume and global function between the two groups. After revascularization, group B had significantly larger LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV), lower LV ejection fraction (LVEF) and higher wall motion score index(WMSI) than those of group A (all P<0.05). Revascularization was followed by significant improvement of LV volume and recovery of global LV function in group A (all P<0.01); however, in group B, after revascularization, deterioration of LVEDV (P<0.05) was observed, moreover LVESV, WMSI and LVEF

  12. The myocardial ischemia evaluated by real-time contrast echocardiography may predict the response to cardiac resynchronization therapy: a large animal study.

    Yongle Chen

    Full Text Available Evidence-based criteria for applying cardiac resynchronization therapy (CRT in patients with ischemic cardiomyopathy are still scarce. The aim of the present study was to evaluate the predictive value of real-time myocardial contrast echocardiography (RT-MCE in a preclinical canine model of ischemic cardiomyopathy who received CRT. Ischemic cardiomyopathy was produced by ligating the first diagonal branch in 20 beagles. Dogs were subsequently divided into two groups that were either treated with bi-ventricular pacing (CRT group or left untreated (control group. RT-MCE was performed at baseline, before CRT, and 4 weeks after CRT. Two-dimensional speckle tracking imaging was used to evaluate the standard deviation of circumferential (Cir12SD, radial (R12SD, and longitudinal (L12SD strains of left ventricular segments at basal as well as middle levels. Four weeks later, the Cir12SD, R12SD, and myocardial blood flow (MBF of the treated group were significantly improved compared to their non-CRT counterparts. Furthermore, MBF values measured before CRT were significantly higher in responders than in non-responders to bi-ventricular pacing. Meanwhile, no significant differences were observed between the responder and non-responder groups in terms of Cir12SD, R12SD, and L12SD. A high degree of correlation was found between MBF values before CRT and LVEF after CRT. When MBF value>24.9 dB/s was defined as a cut-off point before CRT, the sensitivity and specificity of RT-MCE in predicting the response to CRT were 83.3% and 100%, respectively. Besides, MBF values increased significantly in the CRT group compared with the control group after 4 weeks of pacing (49.8±15.5 dB/s vs. 28.5±4.6 dB/s, p<0.05. Therefore, we considered that myocardial perfusion may be superior to standard metrics of LV synchrony in selecting appropriate candidates for CRT. In addition, CRT can improve myocardial perfusion in addition to cardiac synchrony, especially in the setting

  13. Quasi-real-time fluorescence imaging with lifetime dependent contrast

    Jiang, Pei-Chi; Grundfest, Warren S.; Stafsudd, Oscar M.


    Conventional fluorescence lifetime imaging requires complicated algorithms to extract lifetimes of fluorophores and acquisition of multiple data points at progressively longer delay times to characterize tissues. To address diminishing signal-to-noise ratios at these progressively longer time delays, we report a time-resolved fluorescence imaging method, normalized fluorescence yield imaging that does not require the extraction of lifetimes. The concept is to extract the ``contrast'' instead of the lifetime value of the fluorophores by using simple mathematical algorithms. This process converts differences in decay times directly to different intensities. The technique was verified experimentally using a gated iCCD camera and an ultraviolet light-emitting diode light source. It was shown that this method can distinguish between chemical dyes (Fluorescein and Rhodamine-B) and biomedical samples, such as powders of elastin and collagen. Good contrast was obtained between fluorophores that varied by less than 6% in lifetime. Additionally, it was shown that long gate times up to 16 ns achieve good contrast depending upon the samples to be studied. These results support the feasibility of time-resolved fluorescence imaging without lifetime extraction, which has a potential clinical role in noninvasive real-time imaging.

  14. 应用实时心肌超声造影定量评价心功能对急性心肌梗死犬心肌血流量的影响%Real-time myocardial contrast echocardiography evaluates the effection of cardiac function on myocardial blood flow of acute myocardial infarction in mongrel

    吕静; 丁尚伟; 王静; 张艳容; 李秀兰; 王淑彬; 吕清


    Objective:To investigate the effect of cardiac function on myocardial perfusion of the mongrel's acute myocardial infarction model. Method:Eighteen dogs were performed the acute myocardial infarction models by ligating the left anterior descending (LAD) 3 hours, then the contrast agent (C3F8) was injected into femoral vein to perform myocardial contrast echocardiography (MCE) examination, and quantitative calculate the myocardial blood flow (MBF) both of left ventricle middle-anterior wall and middle-posterior wall. Result:Seventeen dogs are successfully performed acute myocardial infraction models. Three hours after ligating LAD, in the A group (n = 7) the eject fraction of left ventricle≥50%, the MBF of middle-anterior wall is obviously lower than the one before ligating LAD (P0. 05) ; in the B group (n=10) the eject fraction of left ventricle 0. 05); Between A group and B group after 3-hour ligating LAD, the MBF of both middle-anterior wall and middle-posterior wall in B group are only slightly lower than those in A group. Conclusion:The cardiac function can influence MBF sometines and maybe induce to undervalue the coronary reserve of flow and overmeasure the narrow degree of coronary, it's helpful to consider the cardiac function's effection using MCE to diagnosis coronary disease.%目的:探讨心功能对心肌梗死犬心肌血流灌注的影响.方法:18只健康杂种犬于前降支分出的第1对角支远端约1 cm处结扎3h,应用心肌超声造影(MCE)定量分析左室前壁中间段和下壁中间段心肌血流量(MBF).结果:17只犬成功建立急性心肌梗死模型.根据结扎3h后左室整体射血分数(EF)分为2组:A组(EF≥50%)7只,B组(EF<50%)10只.B组左室前壁中间段和下壁中间段MBF均低于A组,但2组之间差异无统计学意义;与结扎前相比,2组左室前壁中间段MBF均明显降低,差异有统计学意义(P<0.05),A组左室下壁中间段MBF略升高,B组则降低,但均差异无统计学意义.

  15. Assessment of myocardial perfusion before and after intervention therapy of coronary heart disease by real-time myocardial contrast echocardiography combined with adenosine stress echocardiography%实时心肌声学造影结合腺苷负荷试验对冠心病介入治疗前后心肌灌注的评价

    吴向军; 王庆元; 马风妹


    目的 评价冠心病(CHD)经皮冠状动脉介入治疗(PCI)术前后心肌灌注情况.方法 选择经冠状动脉造影(CAG)证实有冠状动脉狭窄的冠心病患者共42例,对入选的冠状动脉狭窄的患者在行PCI术前后进行经静脉心肌声学造影(MCE)结合腺苷负荷检查,通过心肌显影程度定量判断冠状动脉微循环灌注并记录图像,将治疗前后心肌声学造影结果进行对比分析,评价手术疗效,估计患者预后.结果 23例患者经PCI术治疗后,相关心肌节段的局部所有毛细血管横截面积之和(A)、血流速度(β)、心肌的血流量(A×β)均较冠状动脉介入前显著增加(P <0.05);PCI术后相关心肌节段组与冠状动脉正常者心肌节段组比较,局部所有毛细血管横截面积之和、血流速度、心肌的血流量A、β、A×β仍减低(P<0.05);相关分析显示,随访期EF值和室壁运动记分指数较术前明显增加,并与PCI术治疗后A、β、A×β相关性好(P<0.01).结论 经静脉心肌声学造影结合腺苷负荷检查为冠心病诊断治疗领域提供一种准确、无创评价心肌微循环的临床检测手段;进一步评价经皮冠状动脉介入治疗对改善心肌梗死患者心肌组织灌注的效果.未经再灌注治疗的心肌梗死或心绞痛患者应尽早行择期PCI术,挽救梗死区的缺血心肌,改善左心室功能.%Objective To evaluate the situation of myocardial perfusion before and after percutaneous coronary intervention (PCI).Methods Forty-two patients with coronary artery stenosis confirmed by coronary angiography were selected.Transvenous myocardial contrast echocardiography and adenosine stress echocardiography were administered for the patients.Coronary microcirculation perfusion was quantitatively judged through the extent of myocardial visualization and the images were recorded,the results of myocardial contrast echocardiography were compared,the surgical efficacy was evaluated,and the

  16. Value of real-time myocardial contrast echocardiography in the detection of the myocardial perfusion abnormalities in early diabetic rats model%实时心肌超声造影评价糖尿病早期心肌血流灌注改变的实验研究

    郑磊; 张明; 梁天琳; 茹翱; 刘敏; 赵应征; 田新桥


    Objective: To explore the value of real-time myocardial controast echocardiography to detect myocardial perfusion abnormalities in early diabetic rats.Methods: Among twenty-four male SD rats, twelve rats were randomly selected as DM group which were induced with streptozotocin, the remain twelve rats as normal control group which were induced with buffer solution. Eight weeks after diabetic model established, all rats underwent MCE examination at the resting state. The plateau intensity (A), initial slope of the curve (β) and myocardial blood lfow (A×β) of left ventricular anterior wall at the papillary muscle level were measured in left ventricular short-axis view by MCE. At last, myocardial tissue of the rats were stained with CD31 immuno-histochemistry to detect myocardial microvascular density (MVD). The correlation between A and MVD at DM group was analyzed.Results: Compared with the control group, A and A×β in DM group were obviously lower (P<0.01), β in DM group was also lower, but without statistical difference. The MVD in the DM group was sig-niifcantly decreased compared with the control group (P<0.01). There were signiifcant positive correlations be-tween A and MVD at DM group (r=0.903,P<0.01).Conclusion: MCE can be used to detect the left ventricular myocardial perfusion abnormalities in early diabetic rats and has important application value in diagnosis of the diabetic cardiomyopathy.%目的:探讨实时心肌超声造影(RT-MCE)技术检测糖尿病(DM)早期大鼠心肌血流灌注异常的价值。方法:24只雄性SD大鼠中随机选取12只通过腹腔注射链脲佐菌素建立DM模型(DM组),剩余12只大鼠作为对照,腹腔注射等量枸橼酸缓冲液。模型建成8周后,在静息状态下,对两组大鼠行RT-MCE检查,检测两组大鼠乳头肌水平左室壁感兴趣区的峰值声学强度(A)以及造影剂的灌注速度(β),并计算出心肌血流量(A×β)。RT-MCE检查结束后

  17. Brief communications: visualization of coronary arteries in rats by 3-dimensional real-time contrast echocardiography.

    Ishikura, Fuminobu; Hirayama, Hideo; Iwata, Akiko; Toshida, Tsutomu; Masuda, Kasumi; Otani, Kentaro; Asanuma, Toshihiko; Beppu, Shintaro


    Angiogenesis is under intense investigation to advance the treatment of various ischemic diseases. Small animals, such as mice and rats, are often used for this purpose. However, evaluating the structure of coronary arteries in small animals in situ is not easy. We succeeded in visualizing the coronary artery in rats on 3-dimensional real-time contrast echocardiography using a high-frequency transducer. These methods will be applied for more convenient assessment in a new study, examining issues such as angiogenesis using rats in situ.

  18. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Peruzzini, D.; Viti, J. [MSD lab, Department of Information Engineering, Univ of Florence, Via S.Marta, 3, 50139 Firenze (Italy); Erasmus MC, ’s-Gravendijkwal 230, Faculty Building, Ee 2302, 3015 CE Rotterdam (Netherlands); Tortoli, P. [MSD lab, Department of Information Engineering, Univ of Florence, Via S.Marta, 3, 50139 Firenze (Italy); Verweij, M. D. [Acoustical Wavefield Imaging, ImPhys, Delft Univ Technology, van der Waalsweg 8, 2628 CH Delft (Netherlands); Jong, N. de; Vos, H. J., E-mail: [Erasmus MC, ’s-Gravendijkwal 230, Faculty Building, Ee 2302, 3015 CE Rotterdam (Netherlands); Acoustical Wavefield Imaging, ImPhys, Delft Univ Technology, van der Waalsweg 8, 2628 CH Delft (Netherlands)


    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. “superharmonic” imaging, shows better contrast. However, the superharmonic scattering has a lower signal level compared to e.g. second harmonic signals. This study investigates the contrast-to-tissue ratio (CTR) and signal to noise ratio (SNR) of superharmonic UCA scattering in a tissue/vessel mimicking phantom using a real-time clinical scanner. Numerical simulations were performed to estimate the level of harmonics generated by the microbubbles. Data were acquired with a custom built dual-frequency cardiac phased array probe. Fundamental real-time images were produced while beam formed radiofrequency (RF) data was stored for further offline processing. The phantom consisted of a cavity filled with UCA surrounded by tissue mimicking material. The acoustic pressure in the cavity of the phantom was 110 kPa (MI = 0.11) ensuring non-destructivity of UCA. After processing of the acquired data from the phantom, the UCA-filled cavity could be clearly observed in the images, while tissue signals were suppressed at or below the noise floor. The measured CTR values were 36 dB, >38 dB, and >32 dB, for the second, third, and fourth harmonic respectively, which were in agreement with those reported earlier for preliminary contrast superharmonic imaging. The single frame SNR values (in which ‘signal’ denotes the signal level from the UCA area) were 23 dB, 18 dB, and 11 dB, respectively. This indicates that noise, and not the tissue signal, is the limiting factor for the UCA detection when using the superharmonics in nondestructive mode.

  19. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Peruzzini, D.; Viti, J.; Tortoli, P.; Verweij, M. D.; de Jong, N.; Vos, H. J.


    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. "superharmonic" imaging, shows better contrast. However, the superharmonic scattering has a lower signal level compared to e.g. second harmonic signals. This study investigates the contrast-to-tissue ratio (CTR) and signal to noise ratio (SNR) of superharmonic UCA scattering in a tissue/vessel mimicking phantom using a real-time clinical scanner. Numerical simulations were performed to estimate the level of harmonics generated by the microbubbles. Data were acquired with a custom built dual-frequency cardiac phased array probe. Fundamental real-time images were produced while beam formed radiofrequency (RF) data was stored for further offline processing. The phantom consisted of a cavity filled with UCA surrounded by tissue mimicking material. The acoustic pressure in the cavity of the phantom was 110 kPa (MI = 0.11) ensuring non-destructivity of UCA. After processing of the acquired data from the phantom, the UCA-filled cavity could be clearly observed in the images, while tissue signals were suppressed at or below the noise floor. The measured CTR values were 36 dB, >38 dB, and >32 dB, for the second, third, and fourth harmonic respectively, which were in agreement with those reported earlier for preliminary contrast superharmonic imaging. The single frame SNR values (in which `signal' denotes the signal level from the UCA area) were 23 dB, 18 dB, and 11 dB, respectively. This indicates that noise, and not the tissue signal, is the limiting factor for the UCA detection when using the superharmonics in nondestructive mode.

  20. Real-time phase contrast magnetic resonance imaging for assessment of haemodynamics: from phantom to patients

    Traber, Julius; Wurche, Lennart; Dieringer, Matthias A.; Utz, Wolfgang; Knobelsdorff-Brenkenhoff, Florian von; Schulz-Menger, Jeanette [Max-Delbrueck-Centrum and Charite -Medical University Berlin and HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Working Group on Cardiovascular Magnetic Resonance Imaging, Experimental and Clinical Research Center, Berlin (Germany); Greiser, Andreas [Siemens AG Healthcare Sector, Erlangen (Germany); Jin, Ning [Siemens Medical Solutions USA, Inc., Columbus, OH (United States)


    Assessment of haemodynamics is crucial in many cardiac diseases. Phase contrast MRI (PC-MRI) can accurately access it. Arrhythmia is a major limitation in conventional segmented PC-MRI (SEG). A real-time PC-MRI sequence (RT) could overcome this. We validated RT by comparing to SEG. A prototype RT using shared velocity encoding was tested against SEG at 1.5 T in a flow phantom and consecutively included patients with (n = 55) or without (n = 59) aortic valve disease. In patients with atrial fibrillation (Afib, n = 15), only RT was applied. Phantom: PC images were acquired in front of and behind an interchangeable aortic-stenosis-like inlay. Mean velocity and flow were quantified. Patients: PC images were acquired in the ascending aorta, pulmonary trunk and superior caval vein. Peak velocity, stroke volume and regurgitant fraction were quantified. Phantom: Mean velocities (11 ± 1 to 207 ± 10 cm/s) and flow correlated closely between SEG and RT (r ≥ 0.99, ICC ≥ 0.98, p < 0.0005). Patients without AVD or with aortic regurgitation: Concordance of SEG and RT was excellent regarding peak velocities, stroke volumes (r ≥ 0.91, ICC ≥ 0.94, p < 0.0005) and regurgitant fractions (r = 0.95, ICC = 0.95, p < 0.0005). RT was feasible in all patients with Afib. The real-time sequence is accurate compared to conventional segmented PC-MRI. Its applicability in Afib was shown. Real-time PC-MRI might become a valuable tool in arrhythmia. (orig.)

  1. Assessment of myocardial perfusion and systolic function in patients with coronary artery disease after percutaneous coronary intervention by real-time myocardial contrast echocardiography and two-dimensional strain echocardiography%实时心肌超声造影结合二维应变评价经皮冠状动脉重建术后心肌灌注与收缩功能改变

    钱建芬; 汤裕华; 林银康


    目的 应用实时心肌超声造影(RT-MCE)结合二维应变(2DS)、左心室射血分数(LVEF)评价急性心肌梗死经皮冠状动脉介入术(PCI)后心肌灌注情况与收缩功能的变化.方法对45例急性心肌梗死患者PCI术后1周内行RT-MCE,按照目测定性和半定量法将所有患者分成再灌注良好组、无灌注组和再灌注减弱组,采用Qlab软件计算出各组心肌的充盈速度和心肌的血容量.3组术后3个月复查常规超声心动图测量LVEF及应用2DS软件测量各个节段的收缩期纵向峰值应变(SRs),并将3组LVEF和SRs进行比较.结果 心肌再灌注良好组术后3个月LVEF为(0.60±0.06)%,较术后1周LVEF(0.54±0.05)%增大,差异有统计学意义( t=3.402,P<0.01).术后3个月时,心肌灌注良好组LVEF、左心室心肌SRs分别为(0.60±0.06)%、(-0.96±0.35)s-1,无灌注组分别为(0.41±0.08)%、(-0.43±0.14)s-1,两组比较差异有统计学意义(t= 2.819、3.214,P均<0.01);心肌灌注减弱组LVEF、左心室心肌SRs分别为(0.53±0.05 )%、(-0.59±0.31)s-1,与无灌注组比较差异有统计学意义(t= 2.209、2.418,P<0.05).结论 PCI术后心肌灌注改善与否可以反映心肌功能恢复的趋势,而2DS可较好地定量评价局部心肌收缩功能.%Objective To assess the changes of myocardial perfusion and systolic function in patients with acute myocardial infarction after revascularization by real -time intravenous myocardial contrast echocardiography ( RT-MCE) combined with 2D-3train(2DS). Methods Forty-five patients were examined by RT-MCE within one week after percutaneous coronary intervention (PCI). These patients were divided into groups according to qualitation and demi-quantitation method. The myocardial filling speed and blood volume were calculated by Qlab software. Three months later, the echocardiography was rechecked again to measure the left ventricular ejection fraction (LVEF) and 2DS was used to measure the SRs of every segment of left

  2. Real-Time 12-Lead High-Frequency QRS Electrocardiography for Enhanced Detection of Myocardial Ischemia and Coronary Artery Disease

    Schlegel, Todd T.; Kulecz, Walter B.; DePalma, Jude L.; Feiveson, Alan H.; Wilson, John S.; Rahman, M. Atiar; Bungo, Michael W.


    Several studies have shown that diminution of the high-frequency (HF; 150-250 Hz) components present within the central portion of the QRS complex of an electrocardiogram (ECG) is a more sensitive indicator for the presence of myocardial ischemia than are changes in the ST segments of the conventional low-frequency ECG. However, until now, no device has been capable of displaying, in real time on a beat-to-beat basis, changes in these HF QRS ECG components in a continuously monitored patient. Although several software programs have been designed to acquire the HF components over the entire QRS interval, such programs have involved laborious off-line calculations and postprocessing, limiting their clinical utility. We describe a personal computer-based ECG software program developed recently at the National Aeronautics and Space Administration (NASA) that acquires, analyzes, and displays HF QRS components in each of the 12 conventional ECG leads in real time. The system also updates these signals and their related derived parameters in real time on a beat-to-beat basis for any chosen monitoring period and simultaneously displays the diagnostic information from the conventional (low-frequency) 12-lead ECG. The real-time NASA HF QRS ECG software is being evaluated currently in multiple clinical settings in North America. We describe its potential usefulness in the diagnosis of myocardial ischemia and coronary artery disease.

  3. Real-time contrast enhanced ultrasound imaging of focal splenic lesions

    Li, Wei [Department of Medical Ultrasonics, The First Affiliated Hospital of Sun Yat-Sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Guangzhou (China); Liu, GuangJian, E-mail: [Department of Medical Ultrasonics, The First Affiliated Hospital of Sun Yat-Sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Guangzhou (China); Wang, Wei; Wang, Zhu; Huang, Yang; Xu, ZuoFeng; Xie, XiaoYan [Department of Medical Ultrasonics, The First Affiliated Hospital of Sun Yat-Sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Guangzhou (China); Lu, MingDe [Department of Medical Ultrasonics, The First Affiliated Hospital of Sun Yat-Sen University, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Guangzhou (China); Department of Hepatobiliary Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou (China)


    Objective: To investigate the imaging features of focal splenic lesions (FSLs) on contrast-enhanced ultrasound (CEUS). Methods: Thirty two patients with FSLs proved by pathology were retrospectively analyzed. CEUS was performed using intravenous bolus injection of 2.4 ml sulfur hexafluoride-filled microbubble contrast agent and real time scanning. There were hemangioma (n = 7), lymphoma (n = 8), true cyst (n = 3), infarction (n = 4), hematolymphangioma (n = 2), metastasis tumor (n = 2), and one for each of the following entities extramedullary hemopoiesis, hamartoma, tuberculosis, Langerhans’ cell histiocytosis, inflammatory pseudotumor and myxofibrosarcoma. Results: Among 21 benign lesions, 4 infarctions and 3 cysts presented non-enhancement throughout CEUS scanning, and the other 14 lesions displayed various enhancement levels with 6 (42.9%) hyper-enhancement, 2 (14.3%) iso-enhancement and 6 (42.9%) hypo-enhancement in arterial phase and 11 (78.6%) hypo-enhancement, 1 (7.1%) iso-enhancement and 2 (14.3%) hyper-enhancement in late phase, respectively. The enhancement pattern included 9 (64.3%) homogeneous, 4 (28.6%) heterogeneous and 1 (7.1%) rim-like enhancement. As for the malignant FSLs, all the lesions became completely or extensively hypo-enhancement during the late phase no matter their vascularity during arterial phase. Conclusions: The CEUS features reported in this series may enrich the knowledge for CEUS characterization of FSLs.

  4. Fluorescence interference contrast based approach to study real time interaction of melittin with plasma membranes

    Gupta, Sharad; Gui, Dong; Zandi, Roya; Gill, Sarjeet; Mohideen, Umar


    Melittin is an anti-bacterial and hemolytic toxic peptide found in bee venom. Cell lysis behavior of peptides has been widely investigated, but the exact interaction mechanism of lytic peptides with lipid membranes and its constituents has not been understood completely. In this paper we study the melittin interaction with lipid plasma membranes in real time using non-invasive and non-contact fluorescence interference contrast microscopy (FLIC). Particularly the interaction of melittin with plasma membranes was studied in a controlled molecular environment, where these plasma membrane were composed of saturated lipid, 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) and unsaturated lipid, 1,2-dioleoyl-sn-glycero-3-phosphocholine(DOPC) with and without cholesterol. We found out that melittin starts to form nanometer size pores in the plasma membranes shortly after interacting with membranes. But the addition of cholesterol in plasma membrane slows down the pore formation process. Our results show that inclusion of cholesterol to the plasma membranes make them more resilient towards pore formation and lysis of membrane.

  5. Relationship between HgbA1c and Myocardial Blood Flow Reserve in Patients with Type 2 Diabetes Mellitus: Noninvasive Assessment Using Real-Time Myocardial Perfusion Echocardiography

    Runqing Huang


    Full Text Available To study the relationship between glycosylated hemoglobin (HgbA1c and myocardial perfusion in type 2 diabetes mellitus (T2DM patients, we prospectively enrolled 24 patients with known or suspected coronary artery disease (CAD who underwent adenosine stress by real-time myocardial perfusion echocardiography (RTMPE. HgbA1c was measured at time of RTMPE. Microbubble velocity (β min−1, myocardial blood flow (MBF, mL/min/g, and myocardial blood flow reserve (MBFR were quantified. Quantitative MCE analysis was feasible in all patients (272/384 segments, 71%. Those with HgbA1c > 7.1% had significantly lower βreserve and MBFR than those with HgbA1c ≤ 7.1% (P 2 as normal, HgbA1c > 7.1% significantly increased the risk for abnormal MBFR, (adjusted odds ratio: 1.92, 95% CI: 1.12–3.35, P=0.02. Optimal glycemic control is associated with preservation of MBFR as determined by RTMPE, in T2DM patients at risk for CAD.

  6. An Experimental Study of Myocardial Viability with Myocardial Contrast Echocardiography

    张稳柱; 查道刚; 成官迅; 杨绍青; 刘伊丽


    Background Myocardial blood flow(MBF) can be quantified with myocardial contrast echocardiography (MCE) during a venous in fusion of microbubble. A minimal MBF is required to maintain cell membrane integrity and myocardial viability in ischemic condition. Thus, we hypothesized that MCE could be used to assess myocardial viability by the determination of MBF. Methods and Results MCE was performed at 4 hours after ligation of proximal left anterior descending coronary artery in 7dogs with constant venous infusions of microbubbles.The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1-e-βt), where y is Ⅵ at pulsing interval t, A reflects rnicrovascular cross- sectional area (or myocardial blood volume), and β reflects mean myocardial microbubble velocity. The product of A · β represents MBF. MBF was also obtained by radiolabeled microsphere method servered as reference.MBF derived by radiolabeled microsphere- method in the regions of normal, ischemia and infarction was 1.5±0.3, 0.7±0.3, 0.3±0.2mL·min-1· g-1respectively. The product of A · β obtained by MCE in those regions was 52. 46 ± 15.09, 24.36 ± 3.89, 3.74± ± 3.80 respectively. There was good correlation between normalized MBF and the normalized A · β (r =0. 81, P = 0. 001 ). Conclusions MCE has an ability to determine myocardial viability in myocardial in farction canine model.

  7. A design proposal of real-time monitoring stations: implementation and performance in contrasting environmental conditions

    Jose González


    Full Text Available With the aim of creating a real-time monitoring network for both oceanographic and meteorological data, a monitoring station conceptual design was developed. A common framework for software and electronics was adapted to different environmental conditions using two buoy approaches: one intended for oceanic waters, to be moored up to 30-40 m depth, where waves are the critical design factor, and one for continental waters (rivers, lakes and the inner part of estuaries, where currents are the critical design factor. When structures such as bridges are present in the area, the monitoring station can be installed on these structures, thus reducing its impact and increasing safety. In this paper, the design, implementation, operation and performance of these stations are described. A reliability index is calculated for the longest time series of the three related deployment options on the Galician coast: Cíes (oceanic buoy in front of the Ría de Vigo, Catoira (continental buoy in the Ulla river and Cortegada (installation in a bed in the Ría de Arousa.

  8. Contrast enhanced ultrasound by real-time spatiotemporal filtering of ultrafast images

    Desailly, Yann; Tissier, Anne-Marie; Correas, Jean-Michel; Wintzenrieth, Frédéric; Tanter, Mickaël; Couture, Olivier


    Contrast enhanced ultrasound (CEUS) takes advantage of the nonlinear behaviour of injected microbubbles. If these contrast techniques yield good specificity between bubbles and tissues, they suffer some drawbacks, inherently linked to their dependence on nonlinear content. In recent years, plane-wave ultrasound reached frame rates of up to 20 000 fps. In this study we propose a linear technique for CEUS that takes advantage of these very high frame rates to separate bubbles from tissue without requiring nonlinearities. Data-driven spatiotemporal filtering operations are used to separate different features in the image on the basis of coherence both in space and time. Such filter recently proved to improve Doppler sensitivity (Demene et al 2015 IEEE Trans. Med. Imaging 34 2271-85). In contrast with bubbles, even slow moving ones, tissues are highly coherent both in space and time. Therefore, singular value decomposition (SVD) seems to be a powerful tool for the separation of contrast agents and tissues. In this paper, we apply SVD processing to linear ultrafast ultrasound images for CEUS Doppler. The contrast levels reached by this technique were compared to those of a nonlinear gold standard sequence (PMPI Doppler) through a flow phantom study. The SVD technique reached contrast-to-tissue ratios (CTR) up to 10 dB higher in vitro, and proved to be robust in terms of probe motion and slow flow. A trial was also conducted on a transplanted human kidney, already imaged by means of power Doppler (Claudon et al 1999 Am. J. Roentgenol. 173 41-6) and microbubbles (Kay et al 2009 Clin. Radiol. 64 1081-7). Contrast levels yielded by the SVD technique measured up to 13 dB higher than those of PMPI Doppler.

  9. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Peruzzini, D.; Viti, J.; Tortoli, P.; Verweij, M.D.; De Jong, N.; Vos, H.J.


    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher

  10. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Peruzzini, D.; J. Viti (Jacopo); P. Tortoli (Piero); M.D. Verweij (Martin D.); N. de Jong (Nico); H.J. Vos (Rik)


    textabstractCurrently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the

  11. Quantitative assessment of tumor angiogenesis using real-time motion-compensated contrast-enhanced ultrasound imaging

    Pysz, Marybeth A.; Guracar, Ismayil; Foygel, Kira; Tian, Lu; Willmann, Jürgen K.


    Purpose To develop and test a real-time motion compensation algorithm for contrast-enhanced ultrasound imaging of tumor angiogenesis on a clinical ultrasound system. Materials and methods The Administrative Institutional Panel on Laboratory Animal Care approved all experiments. A new motion correction algorithm measuring the sum of absolute differences in pixel displacements within a designated tracking box was implemented in a clinical ultrasound machine. In vivo angiogenesis measurements (expressed as percent contrast area) with and without motion compensated maximum intensity persistence (MIP) ultrasound imaging were analyzed in human colon cancer xenografts (n = 64) in mice. Differences in MIP ultrasound imaging signal with and without motion compensation were compared and correlated with displacements in x- and y-directions. The algorithm was tested in an additional twelve colon cancer xenograft-bearing mice with (n = 6) and without (n = 6) anti-vascular therapy (ASA-404). In vivo MIP percent contrast area measurements were quantitatively correlated with ex vivo microvessel density (MVD) analysis. Results MIP percent contrast area was significantly different (P < 0.001) with and without motion compensation. Differences in percent contrast area correlated significantly (P < 0.001) with x- and y-displacements. MIP percent contrast area measurements were more reproducible with motion compensation (ICC = 0.69) than without (ICC = 0.51) on two consecutive ultrasound scans. Following anti-vascular therapy, motion-compensated MIP percent contrast area significantly (P = 0.03) decreased by 39.4 ± 14.6 % compared to non-treated mice and correlated well with ex vivo MVD analysis (Rho = 0.70; P = 0.05). Conclusion Real-time motion-compensated MIP ultrasound imaging allows reliable and accurate quantification and monitoring of angiogenesis in tumors exposed to breathing-induced motion artifacts. PMID:22535383

  12. Focal Liver Lesions: Real-time 3-Dimensional Contrast-Enhanced Ultrasonography Compared With 2-Dimensional Contrast-Enhanced Ultrasonography and Magnetic Resonance Imaging.

    Lee, Jung-Chieh; Yan, Kun; Lee, San-Kan; Yang, Wei; Chen, Min-Hua


    This study sought to evaluate the application of real-time 3-dimensional (3D) contrast-enhanced ultrasonography (US) to diagnose focal liver lesions and to compare these results with those from 2-dimensional (2D) contrast-enhanced US and contrast-enhanced magnetic resonance imaging (MRI). Patients with focal liver lesions were examined by 2D contrast-enhanced US, 3D contrast-enhanced US, and contrast-enhanced MRI for lesion characterization, and biopsies and comprehensive clinical diagnoses served as reference standards. The sensitivity, specificity, area under the receiver operating characteristic curve, and intermodality agreement were assessed. The number of contrast agent injections and lesions observed per injection were calculated for 3D and 2D contrast-enhanced US. The number and display quality of the feeding arteries observed with 3D and 2D contrast-enhanced US were assessed. A total of 117 patients with 151 focal liver lesions were enrolled, including 67 cases of hepatocellular carcinoma, 51 cases of liver metastasis, and 33 cases of benign liver lesions. No significant differences were found among the modalities. The sensitivity values for 3D contrast-enhanced US, 2D contrast-enhanced US, and contrast-enhanced MRI were 96%, 95%, and 93%, respectively; the specificity values were 87%, 84%, and 89%; and the area under the receiver operating characteristic curve values were 0.92, 0.90, and 0.92. The intermodality agreement was excellent (κ > 0.77). Fewer contrast agent injections were needed, and more lesions and feeding arteries were more clearly displayed on 3D than 2D contrast-enhanced US (P < .001). Real-time 3D contrast-enhanced US is useful for diagnosing focal liver lesions and for observing feeding arteries with fewer contrast agent injections. © 2017 by the American Institute of Ultrasound in Medicine.

  13. Basic system design of a broad-band real-time phase contrast wavefront sensor for adaptive optics

    Bloemhof, E. E.; Wallace, J. K.


    The most common wavefront sensor for real-time use in high-order adaptive optics systems is the Shack-Hartmann, in part because it is sensitive to a broad optical band. An alternative possibility is based on Zernike's phase contrast technique. Though quite sensitive in principle, at least for monochromatic light, there had been no simple way to obtain the broadband performance needed for competitive sensitivity in an actual adaptive optics system. Recently, we proposed a general achromatization scheme that relies upon the innate π/2 phase shift between the transmitted and reflected beams in a beam splitter. Here, a more detailed study of this broad-band phase contrast wavefront sensor is presented, along with some practical issues concerning component tolerances. These results offer encouraging indications that broad-wavelength-band implementations will be feasible in practice.

  14. Non-invasive volumetric optoacoustic imaging of cardiac cycles in acute myocardial infarction model in real-time

    Lin, Hasiao-Chun Amy; Déan-Ben, Xosé Luís.; Kimm, Melanie; Kosanke, Katja; Haas, Helena; Meier, Reinhard; Lohöfer, Fabian; Wildgruber, Moritz; Razansky, Daniel


    Extraction of murine cardiac functional parameters on a beat-by-beat basis remains challenging with the existing imaging modalities. Novel methods enabling in vivo characterization of functional parameters at a high temporal resolution are poised to advance cardiovascular research and provide a better understanding of the mechanisms underlying cardiac diseases. We present a new approach based on analyzing contrast-enhanced optoacoustic (OA) images acquired at high volumetric frame rate without using cardiac gating or other approaches for motion correction. Acute myocardial infarction was surgically induced in murine models, and the method was modified to optimize for acquisition of artifact-free optoacoustic data. Infarcted hearts could be differentiated from healthy controls based on a significantly higher pulmonary transit time (PTT: infarct 2.07 s vs. healthy 1.34 s), while no statistically significant difference was observed in the heart rate (318 bpm vs. 309 bpm). In combination with the proven ability of optoacoustics to track targeted probes within the injured myocardium, our method is capable of depicting cardiac anatomy, function, and molecular signatures on a beat-by-beat basis, both with high spatial and temporal resolution, thus providing new insights into the study of myocardial ischemia.

  15. Peak flow velocities in the ascending aorta-real-time phase-contrast magnetic resonance imaging vs. cine magnetic resonance imaging and echocardiography.

    Sohns, Jan M; Kowallick, Johannes T; Joseph, Arun A; Merboldt, K Dietmar; Voit, Dirk; Fasshauer, Martin; Staab, Wieland; Frahm, Jens; Lotz, Joachim; Unterberg-Buchwald, Christina


    This prospective study of eight healthy volunteers evaluates peak flow velocities (PFV) in the ascending aorta using real-time phase-contrast magnetic resonance imaging (MRI) in comparison to cine phase-contrast MRI and echocardiography. Flow measurements by echocardiography and cine phase-contrast MRI with breath-holding were performed according to clinical standards. Real-time phase-contrast MRI at 40 ms temporal resolution and 1.3 mm in-plane resolution was based on highly undersampled radial fast low-angle shot (FLASH) sequences with image reconstruction by regularized nonlinear inversion (NLINV). Evaluations focused on the determination of PFV. Linear regressions and Bland-Altman plots were used for comparisons of methods. When averaged across subjects, real-time phase-contrast MRI resulted in PFV of 120±20 cm s(-1) (mean ± SD) in comparison to 122±16 cm s(-1) for cine MRI and 124±20 cm s(-1) for echocardiography. The maximum deviations between real-time phase-contrast MRI and echocardiography ranged from -20 to +14 cm s(-1) (cine MRI: -10 to +12 cm s(-1)). Thus, in general, real-time phase-contrast MRI of cardiac outflow revealed quantitative agreement with cine MRI and echocardiography. The advantages of real-time MRI are measurements during free breathing and access to individual cardiac cycles.

  16. Effect of a real-time tele-transmission system of 12-lead electrocardiogram on the first-aid for athletes with ST-elevation myocardial infarction.

    Zhang, Huan; Song, Donghan; An, Lina


    To study the effect of a real-time tele-transmission system of 12-lead electrocardiogram on door-to-balloon time in athletes with ST-elevation myocardial infarction. A total of 60 athletes with chest pain diagnosed as ST-elevation myocardial infarction (STEMI) from our hospital were randomly divided into group A (n=35) and group B (n=25), the patients in group A transmitted the real-time tele-transmission system of 12-lead electrocardiogram to the chest pain center before arriving in hospital, however, the patients in group B not. The median door-to-balloon time was significant shorter in-group A than group B (38min vs 94 min, p0.05). The median length of stay was significant reduced in-group A (5 days vs 7 days, pelectrocardiogram is beneficial to the pre-hospital diagnosis of STEMI.

  17. Adenosine-stress dynamic real-time myocardial perfusion CT and adenosine-stress first-pass dual-energy myocardial perfusion CT for the assessment of acute chest pain: Initial results

    Weininger, Markus [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Department of Medicine, Division of Cardiology, Medical University of South Carolina, Charleston, SC (United States); Ramachandra, Ashok [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Fink, Christian [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Rowe, Garrett W.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Henzler, Thomas [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany)


    Purpose: Recent innovations in CT enable the evolution from mere morphologic imaging to dynamic and functional testing. We describe our initial experience performing myocardial stress perfusion CT in a clinical population with acute chest pain. Methods and materials: Myocardial stress perfusion CT was performed on twenty consecutive patients (15 men, 5 women; mean age 65 ± 8 years) who presented with acute chest pain and were clinically referred for stress/rest SPECT and cardiac MRI. Prior to CT each patient was randomly assigned either to Group A or to Group B in a consecutive order (10 patients per group). Group A underwent adenosine-stress dynamic real-time myocardial perfusion CT using a novel “shuttle” mode on a 2nd generation dual-source CT. Group B underwent adenosine-stress first-pass dual-energy myocardial perfusion CT using the same CT scanner in dual-energy mode. Two experienced observers visually analyzed all CT perfusion studies. CT findings were compared with MRI and SPECT. Results: In Group A 149/170 myocardial segments (88%) could be evaluated. Real-time perfusion CT (versus SPECT) had 86% (84%) sensitivity, 98% (92%) specificity, 94% (88%) positive predictive value, and 96% (92%) negative predictive value in comparison with perfusion MRI for the detection of myocardial perfusion defects. In Group B all myocardial segments were available for analysis. Compared with MRI, dual-energy myocardial perfusion CT (versus SPECT) had 93% (94%) sensitivity, 99% (98%) specificity, 92% (88%) positive predictive value, and 96% (94%) negative predictive value for detecting hypoperfused myocardial segments. Conclusion: Our results suggest the clinical feasibility of myocardial perfusion CT imaging in patients with acute chest pain. Compared to MRI and SPECT both, dynamic real-time perfusion CT and first-pass dual-energy perfusion CT showed good agreement for the detection of myocardial perfusion defects.

  18. Real-time breath-hold triggering of myocardial perfusion imaging with a novel cadmium-zinc-telluride detector gamma camera

    Buechel, Ronny R.; Pazhenkottil, Aju P.; Herzog, Bernhard A.; Husmann, Lars; Nkoulou, Rene N.; Burger, Irene A.; Valenta, Ines; Wyss, Christophe A.; Ghadri, Jelena R. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland)


    The aim of this study was to assess the ability of real-time breath-hold-triggered myocardial perfusion imaging (MPI) using a novel cadmium-zinc-telluride (CZT) gamma camera to discriminate artefacts from true perfusion defects. A group of 40 patients underwent a 1-day {sup 99m}Tc-tetrofosmin pharmacological stress/rest imaging protocol on a conventional dual detector SPECT gamma camera with and without attenuation correction (AC), immediately followed by scanning on an ultrafast CZT camera with and without real-time breath-hold triggering (instead of AC) by intermittent scanning confined to breath-hold at deep inspiration (using list mode acquisition). We studied the use of breath-hold triggering on the CZT camera and its ability to discriminate artefacts from true perfusion defects using AC SPECT MPI as the reference standard. Myocardial tracer uptake (percent of maximum) from CZT was compared to AC SPECT MPI by intraclass correlation and by calculating Bland-Altman limits of agreement. AC of SPECT MPI identified 19 apparent perfusion defects as artefacts. Of these, 13 were correctly identified and 4 were partially unmasked (decrease in extent and/or severity) by breath-hold triggering of the CZT scan. All perfusion defects verified by SPECT MPI with AC were appropriately documented by CZT with and without breath-hold triggering. This was supported by the quantitative analysis, as the correlation (r) of myocardial tracer uptake between CZT and AC SPECT improved significantly from 0.81 to 0.90 (p<0.001) when applying breath-hold triggering. Similarly, Bland-Altman limits of agreement were narrower for CZT scans with breath-hold triggering. This novel CZT camera allows real-time breath-hold triggering as a potential alternative to AC to assist in the discrimination of artefacts from true perfusion defects. (orig.)

  19. The Natural History of Kidney Graft Cortical Microcirculation Determined by Real-Time Contrast-Enhanced Sonography (RT-CES.

    Carlos Jiménez

    Full Text Available Kidney transplantation is the therapy of choice for end-stage kidney disease. Graft's life span is shorter than expected due in part to the delayed diagnosis of various complications, specifically those related to silent progression. It is recognized that serum creatinine levels and proteinuria are poor markers of mild kidney lesions, which results in delayed clinical information. There are many investigation looking for early markers of graft damage. Decreasing kidney graft cortical microcirculation has been related to poor prognosis in kidney transplantation. Cortical capillary blood flow (CCBF can be measured by real-time contrast-enhanced sonography (RT-CES. Our aim was to describe the natural history of CCBF over time under diverse conditions of kidney transplantation, to explore the influence of donor conditions and recipient events, and to determine the capacity of CCBF for predicting renal function in medium term.RT-CES was performed in 79 consecutive kidney transplant recipients during the first year under regular clinical practice. Cortical capillary blood flow was measured. Clinical variables were analyzed. The influence of CCBF has been determined by univariate and multivariate analysis using mixed regression models based on sequential measurements for each patient over time. We used a first-order autoregression model as the structure of the covariation between measures. The post-hoc comparisons were considered using the Bonferroni correction.The CCBF values varied significantly over the study periods and were significantly lower at 48 h and day 7. Brain-death donor age and CCBF levels showed an inverse relationship (r: -0.62, p<0.001. Living donors showed higher mean CCBF levels than brain-death donors at each point in the study. These significant differences persisted at month 12 (54.5 ± 28.2 vs 33.7 ± 30 dB/sec, living vs brain-death donor, respectively, p = 0.004 despite similar serum creatinine levels (1.5 ± 0.3 and 1.5 ± 0

  20. Real-time phase-contrast flow MRI of the ascending aorta and superior vena cava as a function of intrathoracic pressure (Valsalva manoeuvre)

    Kowallick, J T; Joseph, A A; Unterberg-Buchwald, C; Fasshauer, M; van Wijk, K; Merboldt, K D; Voit, D; Frahm, J; Lotz, J


    Objective: Real-time phase-contrast flow MRI at high spatiotemporal resolution was applied to simultaneously evaluate haemodynamic functions in the ascending aorta (AA) and superior vena cava (SVC) during elevated intrathoracic pressure (Valsalva manoeuvre). Methods: Real-time phase-contrast flow MRI at 3 T was based on highly undersampled radial gradient-echo acquisitions and phase-sensitive image reconstructions by regularized non-linear inversion. Dynamic alterations of flow parameters were obtained for 19 subjects at 40-ms temporal resolution, 1.33-mm in-plane resolution and 6-mm section thickness. Real-time measurements were performed during normal breathing (10 s), increased intrathoracic pressure (10 s) and recovery (20 s). Results: Real-time measurements were technically successful in all volunteers. During the Valsalva manoeuvre (late strain) and relative to values during normal breathing, the mean peak flow velocity and flow volume decreased significantly in both vessels (p < 0.001) followed by a return to normal parameters within the first 10 s of recovery in the AA. By contrast, flow in the SVC presented with a brief (1–2 heartbeats) but strong overshoot of both the peak velocity and blood volume immediately after pressure release followed by rapid normalization. Conclusion: Real-time phase-contrast flow MRI may assess cardiac haemodynamics non-invasively, in multiple vessels, across the entire luminal area and at high temporal and spatial resolution. Advances in knowledge: Future clinical applications of this technique promise new insights into haemodynamic alterations associated with pre-clinical congestive heart failure or diastolic dysfunction, especially in cases where echocardiography is technically compromised. PMID:25074791

  1. Real-time systems

    Badr, Salah M.; Bruztman, Donald P.; Nelson, Michael L.; Byrnes, Ronald Benton


    This paper presents an introduction to the basic issues involved in real-time systems. Both real-time operating sys and real-time programming languages are explored. Concurrent programming and process synchronization and communication are also discussed. The real-time requirements of the Naval Postgraduate School Autonomous Under Vehicle (AUV) are then examined. Autonomous underwater vehicle (AUV), hard real-time system, real-time operating system, real-time programming language, real-time sy...

  2. Real-time contrast-enhanced ultrasound determination of microvascular blood volume in abdominal subcutaneous adipose tissue in man. Evidence for adipose tissue capillary recruitment

    Tobin, L; Simonsen, L; Bülow, J


    the basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection...... of ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain......-gauge plethysmography was used to measure the adipose tissue and forearm blood flow, respectively. Ultrasound signal intensity of the first plateau phases was 27 ± dB in the abdominal subcutaneous adipose tissue and 18 ± 2 dB (P muscle. The reproducibility of the measurements was good...

  3. Real-time contrast-enhanced ultrasound determination of microvascular blood volume in abdominal subcutaneous adipose tissue in man. Evidence for adipose tissue capillary recruitment

    Tobin, L; Simonsen, L; Bülow, J


    The adipose tissue metabolism is dependent on its blood perfusion. During lipid mobilization e.g. during exercise and during lipid deposition e.g. postprandial, adipose tissue blood flow is increased. This increase in blood flow may involve capillary recruitment in the tissue. We investigated...... the basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection...... of ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain...

  4. A new scheme for real-time high-contrast imaging in lung cancer radiotherapy: a proof-of-concept study

    Yan, Hao; Tian, Zhen; Shao, Yiping; Jiang, Steve B.; Jia, Xun


    Visualization of anatomy in real time is of critical importance for motion management in lung cancer radiotherapy. To achieve real-time, and high-contrast in-treatment imaging, we propose a novel scheme based on the measurement of Compton scatter photons. In our method, a slit x-ray beam along the superior-inferior direction is directed to the patient, (intersecting the lung region at a 2D plane) containing most of the tumor motion trajectory. X-ray photons are scattered off this plane primarily due to the Compton interaction. An imager with a pinhole or a slat collimator is placed at one side of the plane to capture the scattered photons. The resulting image, after correcting for incoming fluence inhomogeneity, x-ray attenuation, scatter angle variation, and outgoing beam geometry, represents the linear attenuation coefficient of Compton scattering. This allows the visualization of the anatomy on this plane. We performed Monte Carlo simulation studies both on a phantom and a patient for proof-of-principle purposes. In the phantom case, a small tumor-like structure could be clearly visualized. The contrast-resolution calculated using tumor/lung as foreground/background for kV fluoroscopy, cone beam computed tomography (CBCT), and scattering image were 0.037, 0.70, and 0.54, respectively. In the patient case, tumor motion could be clearly observed in the scatter images. Imaging dose to the voxels directly exposed by the slit beam was ~0.4 times of that under a single CBCT projection. These studies demonstrated the potential feasibility of the proposed imaging scheme to capture the instantaneous anatomy of a patient on a 2D plane with a high image contrast. Clear visualization of the tumor motion may facilitate marker-less tumor tracking.

  5. Assessment of Myocardial Perfusion and Systolic Function in Patients with Coronary Artery Disease after Coronary Artery Bypass Surgery by Myocardial Contrast Echocardiography and Two-dimensional Strain Echocardiography

    Rong LIU; Youbin DENG; Xiaojun BI; Yani LIU; Li XIONG; Liuping CHEN


    The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echo-cardiography (RT-MCE) combined with two-dimensional strain echocardiography was assessed.Twenty patients underwent intravenous RT-MCE by intravenous injections of Sono Vue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before, and two weeks and three months af-ter coronary artery bypass surgery, and the peak systolic longitudinal strain was measured. The results showed that myocardial perfusion was significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitu-dinal strain three months after bypass surgery was significantly higher than that before operation [(-15.78±5.91)% vs (-10.45±8.31)%, P0.05]. It was con-cluded that whether or not the improvement of myocardial perfusion can mirror the recovery trend of regional systolic function, two-dimensional strain echocardiography can observe dynamic change of re-gional systolic function. The combination of myocardial perfusion with two-dimensional strain echocar-diography can more accurately assess the curative effectiveness of coronary artery bypass surgery.

  6. Contrast-enhanced MRI of murine myocardial infarction - part II.

    Coolen, Bram F; Paulis, Leonie E M; Geelen, Tessa; Nicolay, Klaas; Strijkers, Gustav J


    Mouse models are increasingly used to study the pathophysiology of myocardial infarction in vivo. In this area, MRI has become the gold standard imaging modality, because it combines high spatial and temporal resolution functional imaging with a large variety of methods to generate soft tissue contrast. In addition, (target-specific) MRI contrast agents can be employed to visualize different processes in the cascade of events following myocardial infarction. Here, the MRI sequence has a decisive role in the detection sensitivity of a contrast agent. However, a straightforward translation of clinically available protocols for human cardiac imaging to mice is not feasible, because of the small size of the mouse heart and its extremely high heart rate. This has stimulated intense research in the development of cardiac MRI protocols specifically tuned to the mouse with regard to timing parameters, acquisition strategies, and ECG- and respiratory-triggering methods to find an optimal trade-off between sensitivity, scan time, and image quality. In this review, a detailed analysis is given of the pros and cons of different mouse cardiac MR imaging methodologies and their application in contrast-enhanced MRI of myocardial infarction. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Contrast-enhanced, real-time volumetric ultrasound imaging of tissue perfusion: preliminary results in a rabbit model of testicular torsion

    Paltiel, H. J.; Padua, H. M.; Gargollo, P. C.; Cannon, G. M., Jr.; Alomari, A. I.; Yu, R.; Clement, G. T.


    Contrast-enhanced ultrasound (US) imaging is potentially applicable to the clinical investigation of a wide variety of perfusion disorders. Quantitative analysis of perfusion is not widely performed, and is limited by the fact that data are acquired from a single tissue plane, a situation that is unlikely to accurately reflect global perfusion. Real-time perfusion information from a tissue volume in an experimental rabbit model of testicular torsion was obtained with a two-dimensional matrix phased array US transducer. Contrast-enhanced imaging was performed in 20 rabbits during intravenous infusion of the microbubble contrast agent Definity® before and after unilateral testicular torsion and contralateral orchiopexy. The degree of torsion was 0° in 4 (sham surgery), 180° in 4, 360° in 4, 540° in 4, and 720° in 4. An automated technique was developed to analyze the time history of US image intensity in experimental and control testes. Comparison of mean US intensity rate of change and of ratios between mean US intensity rate of change in experimental and control testes demonstrated good correlation with testicular perfusion and mean perfusion ratios obtained with radiolabeled microspheres, an accepted 'gold standard'. This method is of potential utility in the clinical evaluation of testicular and other organ perfusion.

  8. Factors influencing real time internal structural visualization and dynamic process monitoring in plants using synchrotron-based phase contrast X-ray imaging.

    Karunakaran, Chithra; Lahlali, Rachid; Zhu, Ning; Webb, Adam M; Schmidt, Marina; Fransishyn, Kyle; Belev, George; Wysokinski, Tomasz; Olson, Jeremy; Cooper, David M L; Hallin, Emil


    Minimally invasive investigation of plant parts (root, stem, leaves, and flower) has good potential to elucidate the dynamics of plant growth, morphology, physiology, and root-rhizosphere interactions. Laboratory based absorption X-ray imaging and computed tomography (CT) systems are extensively used for in situ feasibility studies of plants grown in natural and artificial soil. These techniques have challenges such as low contrast between soil pore space and roots, long X-ray imaging time, and low spatial resolution. In this study, the use of synchrotron (SR) based phase contrast X-ray imaging (PCI) has been demonstrated as a minimally invasive technique for imaging plants. Above ground plant parts and roots of 10 day old canola and wheat seedlings grown in sandy clay loam soil were successfully scanned and reconstructed. Results confirmed that SR-PCI can deliver good quality images to study dynamic and real time processes such as cavitation and water-refilling in plants. The advantages of SR-PCI, effect of X-ray energy, and effective pixel size to study plant samples have been demonstrated. The use of contrast agents to monitor physiological processes in plants was also investigated and discussed.

  9. Real-time tracking of dissociation of hyperpolarized 89Y-DTPA: a model for degradation of open-chain Gd3+ MRI contrast agents

    Ferguson, Sarah; Niedbalski, Peter; Parish, Christopher; Kiswandhi, Andhika; Kovacs, Zoltan; Lumata, Lloyd

    Gadolinium (Gd) complexes are widely used relaxation-based clinical contrast agents in magnetic resonance imaging (MRI). Gd-based MRI contrast agents with open-chain ligand such as Gd-DTPA, commercially known as magnevist, are less stable compared to Gd complexes with macrocyclic ligands such as GdDOTA (Dotarem). The dissociation of Gd-DPTA into Gd ion and DTPA ligand under certain biological conditions such as high zinc levels can potentially cause kidney damage. Since Gd is paramagnetic, direct NMR detection of the Gd-DTPA dissociation is quite challenging due to ultra-short relaxation times. In this work, we have investigated Y-DTPA as a model for Gd-DPTA dissociation under high zinc content solutions. Using dissolution dynamic nuclear polarization (DNP), the 89Y NMR signal is amplified by several thousand-fold. Due to the the relatively long T1 relaxation time of 89Y which translates to hyperpolarization lifetime of several minutes, the dissociation of Y-DTPA can be tracked in real-time by hyperpolarized 89Y NMR spectroscopy. Dissociation kinetic rates and implications on the degradation of open-chain Gd3+ MRI contrast agents will be discussed. This work was supported by the U.S. Department of Defense Award Number W81XWH-14-1-0048 and by the Robert A. Welch Foundation research Grant Number AT-1877.

  10. Automatic Characterization of Myocardial Perfusion in Contrast Enhanced MRI

    Positano, Vincenzo; Santarelli, Maria Filomena; Landini, Luigi


    The use of contrast medium in cardiac MRI allows joining the high-resolution anatomical information provided by standard magnetic resonance with functional information obtained by means of the perfusion of contrast agent in myocardial tissues. The current approach to perfusion MRI characterization is the qualitative one, based on visual inspection of images. Moving to quantitative analysis requires extraction of numerical indices of myocardium perfusion by analysis of time/intensity curves related to the area of interest. The main problem in quantitative image sequence analysis is the heart movement, mainly due to patient respiration. We propose an automatic procedure based on image registration, segmentation of the myocardium, and extraction and analysis of time/intensity curves. The procedure requires a minimal user interaction, is robust with respect to the user input, and allows effective characterization of myocardial perfusion. The algorithm was tested on cardiac MR images acquired from voluntaries and in clinical routine.

  11. Comparison of adenosine stress and dobutamine stress by real-time myocardial contrast echocardiography in detecting myocardium ischemia in dogs

    XING Yan-qiu; HOU Bo-wen; ZHANG Yun; LIU Xiang-qun; GAO Hai-qing


    spectively. Conclusions Even small distal infarcts can be detected by RTPI; peri-infarct ischemia can be accurately recognized by RTPI during stress; adenosine and dobutamine stress appear equally reliable in the RTPI evaluation of peri-infarct ischemia.

  12. Effect of streptozotocin-induced diabetes on myocardial blood flow reserve assessed by myocardial contrast echocardiography in rats

    Weytjens Caroline; Garbar Christian; Degaillier Céline; Hernot Sophie; Droogmans Steven; Cosyns Bernard; Roosens Bram; Schoors Danny; Lahoutte Tony; Franken Philippe R; Van Camp Guy


    Abstract The role of structural and functional abnormalities of small vessels in diabetes cardiomyopathy remains unclear. Myocardial contrast echocardiography allows the quantification of myocardial blood flow at rest and during dipyridamole infusion. The aim of the study was to determine the myocardial blood flow reserve in normal rats compared with Streptozotocin-induced diabetic rats using contrast echocardiography. Methods We prospectively studied 40 Wistar rats. Diabetes was induced by ...

  13. Real-time phase-contrast x-ray imaging: a new technique for the study of animal form and function

    Waters James S


    Full Text Available Abstract Background Despite advances in imaging techniques, real-time visualization of the structure and dynamics of tissues and organs inside small living animals has remained elusive. Recently, we have been using synchrotron x-rays to visualize the internal anatomy of millimeter-sized opaque, living animals. This technique takes advantage of partially-coherent x-rays and diffraction to enable clear visualization of internal soft tissue not viewable via conventional absorption radiography. However, because higher quality images require greater x-ray fluxes, there exists an inherent tradeoff between image quality and tissue damage. Results We evaluated the tradeoff between image quality and harm to the animal by determining the impact of targeted synchrotron x-rays on insect physiology, behavior and survival. Using 25 keV x-rays at a flux density of 80 μW/mm-2, high quality video-rate images can be obtained without major detrimental effects on the insects for multiple minutes, a duration sufficient for many physiological studies. At this setting, insects do not heat up. Additionally, we demonstrate the range of uses of synchrotron phase-contrast imaging by showing high-resolution images of internal anatomy and observations of labeled food movement during ingestion and digestion. Conclusion Synchrotron x-ray phase contrast imaging has the potential to revolutionize the study of physiology and internal biomechanics in small animals. This is the only generally applicable technique that has the necessary spatial and temporal resolutions, penetrating power, and sensitivity to soft tissue that is required to visualize the internal physiology of living animals on the scale from millimeters to microns.

  14. An eigenvalue approach for the automatic scaling of unknowns in model-based reconstructions: Application to real-time phase-contrast flow MRI.

    Tan, Zhengguo; Hohage, Thorsten; Kalentev, Oleksandr; Joseph, Arun A; Wang, Xiaoqing; Voit, Dirk; Merboldt, K Dietmar; Frahm, Jens


    The purpose of this work is to develop an automatic method for the scaling of unknowns in model-based nonlinear inverse reconstructions and to evaluate its application to real-time phase-contrast (RT-PC) flow magnetic resonance imaging (MRI). Model-based MRI reconstructions of parametric maps which describe a physical or physiological function require the solution of a nonlinear inverse problem, because the list of unknowns in the extended MRI signal equation comprises multiple functional parameters and all coil sensitivity profiles. Iterative solutions therefore rely on an appropriate scaling of unknowns to numerically balance partial derivatives and regularization terms. The scaling of unknowns emerges as a self-adjoint and positive-definite matrix which is expressible by its maximal eigenvalue and solved by power iterations. The proposed method is applied to RT-PC flow MRI based on highly undersampled acquisitions. Experimental validations include numerical phantoms providing ground truth and a wide range of human studies in the ascending aorta, carotid arteries, deep veins during muscular exercise and cerebrospinal fluid during deep respiration. For RT-PC flow MRI, model-based reconstructions with automatic scaling not only offer velocity maps with high spatiotemporal acuity and much reduced phase noise, but also ensure fast convergence as well as accurate and precise velocities for all conditions tested, i.e. for different velocity ranges, vessel sizes and the simultaneous presence of signals with velocity aliasing. In summary, the proposed automatic scaling of unknowns in model-based MRI reconstructions yields quantitatively reliable velocities for RT-PC flow MRI in various experimental scenarios. Copyright © 2017 John Wiley & Sons, Ltd.

  15. Characterization of macrolesions induced by myocardial contrast enabled therapy (MCET)

    Zhu, Yiying I.; Miller, Douglas L.; Dou, Chunyan; Kripfgans, Oliver D.


    Intermittent high intensity ultrasound pulses with circulating contrast agent microbubbles can induce scattered cavitation microlesions of potential value for myocardial reduction therapy. In this study, a computer-aided evaluation scheme of the effective treated volume was implemented in order to optimize ultrasound pulse parameters, exposure duration, and contrast agent dose. Rats with Evans blue injections were treated with 1.5 MHz focused ultrasound bursts. Evans blue staining indicates lethal cardiomyocytic injury. After frozen in compound on dry ice, each heart was sectioned to provide samples covering the entire exposed myocardial volume. Both brightfield and fluorescence images of 25 tissue sections were taken. Tissue detection and microlesion detection were first done based on the 2D images to form microlesion masks containing the outline of the heart and the dead cell regions. Image registration was then performed on the microlesion masks to reconstruct a volume-based model according to the morphology of the heart. The therapeutic beam path was estimated from 3D stacked microlesions, and finally the total impacted volume with microlesions, here termed macrolesion, was characterized along the therapeutic beam axis. Radially symmetric fractional macrolesions were characterized via stepping disks of variable radius determined by the local distribution of microlesions. Treated groups show significant macrolesions with approximately 100 µL volume, an average radius of 2.5 mm, 6 mm length, and 13% lesion density compared to zero radius, length and lesion density for the sham group.

  16. Comparison of transient arterial occlusion and muscle exercise provocation for assessment of perfusion reserve in skeletal muscle with real-time contrast-enhanced ultrasound

    Krix, Martin, E-mail: [German Cancer Research Center, Research Program Imaging and Radiooncology, Department of Radiology, INF 280, D-69120 Heidelberg (Germany); Bracco Imaging Germany, Max-Stromeyer-Str. 116, D-78467 Konstanz (Germany); Krakowski-Roosen, Holger [German Cancer Research Center, Department of Translational Oncology, INF 280, D-69120 Heidelberg (Germany); Armarteifio, Erick [University Hospital of Heidelberg, Department of Diagnostic and Interventional Radiology, INF 110, D-69120 Heidelberg (Germany); Fuerstenberger, Susanne [University Hospital of Heidelberg, Department of Vascular Surgery, INF 110, D-69120 Heidelberg (Germany); Delorme, Stefan [German Cancer Research Center, Research Program Imaging and Radiooncology, Department of Radiology, INF 280, D-69120 Heidelberg (Germany); Kauczor, Hans-Ulrich; Weber, Marc-Andre [University Hospital of Heidelberg, Department of Diagnostic and Interventional Radiology, INF 110, D-69120 Heidelberg (Germany)


    Objective: Contrast-enhanced ultrasound (CEUS) is able to quantify muscle perfusion and changes in perfusion due to muscle exercise in real-time. However, reliable measurement of standardized muscle exercise is difficult to perform in clinical examinations. We compared perfusion reserve assessed by CEUS after transient arterial occlusion and exercise to find the most suitable measurement for clinical application. Methods: Contrast pulse sequencing (7 MHz) during continuous IV infusion of SonoVue (4.8 mL/300 s) was used in 8 healthy volunteers to monitor muscle perfusion of the gastrocnemius muscle during transient (1 min) arterial occlusion produced by a thigh cuff of a venous occlusion plethysmograph. Isometric muscle exercise (50% of individual maximum strength for 20 s) was subsequently performed during the same examination, and several CEUS parameters obtained from ultrasound-signal-intensity-time curves and its calculation errors were compared. Results: The mean maximum local blood volume after occlusion was 13.9 [{approx}mL] (range, 4.5-28.8 [{approx}mL]), and similar values were measured after sub-maximum exercise 13.8 [{approx}mL], (range, 4.6-22.2 [{approx}mL]. The areas under the curve during reperfusion vs. recovery were also similar (515.2 {+-} 257.5 compared to 482.2 {+-} 187.5 [{approx}mL s]) with a strong correlation (r = 0.65), as were the times to maximum (15.3 s vs. 15.9 s), with a significantly smaller variation for the occlusion method ({+-}2.1 s vs. {+-}9.0 s, p = 0.03). The mean errors for all calculated CEUS parameters were lower for the occlusion method than for the exercise test. Conclusions: CEUS muscle perfusion measurements can be easily performed after transient arterial occlusion. It delivers data which are comparable to CEUS measurements after muscle exercise but with a higher robustness. This method can be easily applied in clinical examination of patients with e.g. PAOD or diabetic microvessel diseases to assess perfusion reserve.

  17. Real Time Systems

    Christensen, Knud Smed


    Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....

  18. Real Time Systems

    Christensen, Knud Smed


    Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....

  19. 3D perfusion mapping in the intact mouse heart after myocardial infarction using myocardial contrast echocardiography

    Li, Yinbo; Yang, Zequan; French, Brent A.; Hossack, John A.


    An intact mouse model of surgically-induced myocardial infarction (MI) caused by permanent occlusion of the Left Anterior Descending (LAD) coronary artery was studied. Normal mice with no occlusion were also studied as controls. For each mouse, contrast enhanced ultrasound images of the heart were acquired in parallel cross-sections perpendicular to the sternum at millimeter increments. For accurate 3D reconstruction, ECG gating and a tri-axial adjustable micromanipulator were used for temporal and spatial registration. Ultrasound images at steady-state of blood refilling were color-coded in each slice to show relative perfusion. Myocardial perfusion defects and necrosis were also examined postmortem by staining with Phthalo blue and TTC red dyes. Good correlation (R>0.93) in perfused area size was observed between in vivo measurements and histological staining. A 3D multi-slice model and a 3D rendering of perfusion distribution were created and showed a promising match with postmortem results, lending further credence to its use as a more comprehensive and more reliable tool for in vivo assessment of myocardial perfusion than 2D tomographic analysis.

  20. Real-time shadows

    Eisemann, Elmar; Assarsson, Ulf; Wimmer, Michael


    Important elements of games, movies, and other computer-generated content, shadows are crucial for enhancing realism and providing important visual cues. In recent years, there have been notable improvements in visual quality and speed, making high-quality realistic real-time shadows a reachable goal. Real-Time Shadows is a comprehensive guide to the theory and practice of real-time shadow techniques. It covers a large variety of different effects, including hard, soft, volumetric, and semi-transparent shadows.The book explains the basics as well as many advanced aspects related to the domain

  1. Early and Delayed Myocardial Enhancement in Myocardial Infarction Using Two-Phase Contrast-Enhanced Multidetector-Row CT

    Kim, Young-Whan; Han, Seong-Wook; Seo, Joon-Beom


    Objective The purpose of this study was to describe the myocardial enhancement patterns in patients with myocardial infarction using two-phase contrast-enhanced multidetector-row computed tomography (MDCT). Materials and Methods Twenty-three patients with clinically proven myocardial infarction (17 acute myocardial infarction [AMI] and 6 chronic myocardial infarction [CMI]) were examined with two-phase contrast-enhanced ECG-gated MDCT. The presence, location, and patterns of myocardial enhancement on two-phase MDCT images were compared with infarcted myocardial territories determined by using electrocardiogram, echocardiography, thallium-201 single photon emission computed tomography, catheter and MDCT coronary angiography. Results After clinical assessment, the presence of myocardial infarctions were found in 27 territories (19 AMI and 8 CMI) of 23 patients. Early perfusion defects were observed in 30 territories of all 23 patients. Three territories not corresponding to a myocardial infarction were detected in three patients with AMI and were associated with artifacts. Fourteen of perfusion defects were in the left anterior descending artery territory, four in the left circumflex artery territory, and nine in the right coronary artery territory. Delayed enhancement was observed in 25 territories (17 AMI and 8 CMI) of 21 patients. Delayed enhancement patterns were variable. Transmural early perfusion defects (n =12) were closely associated with transmural late enhancement (n = 5) and subendocardial residual defect with subepicardial late enhancement (n = 5). Conclusion Myocardial infarction showed early perfusion defects and variable delayed enhancement patterns on two-phase contrast-enhanced MDCT. Delayed enhancement technique of MDCT could provide additional information of the location and extent of infarcted myocardium, and could be useful to plan appropriate therapeutic strategies in patients with AMI. PMID:17420626

  2. Early and Delayed Myocardial Enhancement in Myocardial Infarction Using Two-Phase Contrast-Enhanced Multidetector-Row CT

    Ko, Sung-Min; Kim, Young-Whan; Han, Seong-Wook [University of Keimyung College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Seo, Joon-Beom [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)


    The purpose of this study was to describe the myocardial enhancement patterns in patients with myocardial infarction using two-phase contrast enhanced multidetector-row computed tomography (MDCT). Twenty-three patients with clinically proven myocardial infarction (17 acute myocardial infarction [AMI] and 6 chronic myocardial infarction [CMI]) were examined with two-phase contrast-enhanced ECG-gated MDCT. The presence, location, and patterns of myocardial enhancement on two phase MDCT images were compared with infarcted myocardial territories determined by using electrocardiogram, echocardiography, thallium-201 single photon emission computed tomography, catheter and MDCT coronary angiography. After clinical assessment, the presence of myocardial infarctions were found in 27 territories (19 AMI and 8 CMI) of 23 patients. Early perfusion defects were observed in 30 territories of all 23 patients. Three territories not corresponding to a myocardial infarction were detected in three patients with AMI and were associated with artifacts. Fourteen of perfusion defects were in the left anterior descending artery territory, four in the left circumflex artery territory, and nine in the right coronary artery territory. Delayed enhancement was observed in 25 territories (17 AMI and 8 CMI) of 21 patients. Delayed enhancement patterns were variable. Transmural early perfusion defects (n =12) were closely associated with transmural late enhancement (n = 5) and subendocardial residual defect with subepicardial late enhancement (n = 5). Myocardial infarction showed early perfusion defects and variable delayed enhancement patterns on two-phase contrast-enhanced MDCT. Delayed enhancement technique of MDCT could provide additional information of the location and extent of infarcted myocardium, and could be useful to plan appropriate therapeutic strategies in patients with AMI.

  3. Measurement of myocardial perfusion and infarction size using computer-aided diagnosis system for myocardial contrast echocardiography.

    Du, Guo-Qing; Xue, Jing-Yi; Guo, Yanhui; Chen, Shuang; Du, Pei; Wu, Yan; Wang, Yu-Hang; Zong, Li-Qiu; Tian, Jia-Wei


    Proper evaluation of myocardial microvascular perfusion and assessment of infarct size is critical for clinicians. We have developed a novel computer-aided diagnosis (CAD) approach for myocardial contrast echocardiography (MCE) to measure myocardial perfusion and infarct size. Rabbits underwent 15 min of coronary occlusion followed by reperfusion (group I, n = 15) or 60 min of coronary occlusion followed by reperfusion (group II, n = 15). Myocardial contrast echocardiography was performed before and 7 d after ischemia/reperfusion, and images were analyzed with the CAD system on the basis of eliminating particle swarm optimization clustering analysis. The myocardium was quickly and accurately detected using contrast-enhanced images, myocardial perfusion was quantitatively calibrated and a color-coded map calibrated by contrast intensity and automatically produced by the CAD system was used to outline the infarction region. Calibrated contrast intensity was significantly lower in infarct regions than in non-infarct regions, allowing differentiation of abnormal and normal myocardial perfusion. Receiver operating characteristic curve analysis documented that -54-pixel contrast intensity was an optimal cutoff point for the identification of infarcted myocardium with a sensitivity of 95.45% and specificity of 87.50%. Infarct sizes obtained using myocardial perfusion defect analysis of original contrast images and the contrast intensity-based color-coded map in computerized images were compared with infarct sizes measured using triphenyltetrazolium chloride staining. Use of the proposed CAD approach provided observers with more information. The infarct sizes obtained with myocardial perfusion defect analysis, the contrast intensity-based color-coded map and triphenyltetrazolium chloride staining were 23.72 ± 8.41%, 21.77 ± 7.8% and 18.21 ± 4.40% (% left ventricle) respectively (p > 0.05), indicating that computerized myocardial contrast echocardiography can

  4. Real-time phase-contrast x-ray imaging: a new technique for the study of animal form and function.

    Socha, J.; Lee, W.; Chicago Field Museum; Arizona State Univ.


    Despite advances in imaging techniques, real-time visualization of the structure and dynamics of tissues and organs inside small living animals has remained elusive. Recently, we have been using synchrotron x-rays to visualize the internal anatomy of millimeter-sized opaque, living animals. This technique takes advantage of partially-coherent x-rays and diffraction to enable clear visualization of internal soft tissue not viewable via conventional absorption radiography. However, because higher quality images require greater x-ray fluxes, there exists an inherent tradeoff between image quality and tissue damage.

  5. Assessment of real-time myocardial uptake and enzymatic conversion of hyperpolarized [1-¹³C]pyruvate in pigs using slice selective magnetic resonance spectroscopy

    Menichetti, Luca; Frijia, Francesca; Flori, Alessandra


    such as the heart, through the quantification of kinetic patterns under both normal and pathological conditions. In this study we assessed myocardial uptake and metabolism of hyperpolarized [1-¹³C]pyruvate in anesthetized pigs. Pyruvate metabolism was studied at baseline and during dobutamine-induced stimulation....... We applied a numerical approach for spectral analysis and kinetic fitting (LSFIT/KIMOfit), making a comparison with a well-known jMRUI/AMARES analysis and γ-variate function, and we estimated the apparent conversion rate of hyperpolarized [1-¹³C]pyruvate into its downstream metabolites [1-¹³C......]lactate, [1-¹³C]alanine and [¹³C]bicarbonate in a 3 T MR scanner. We detected an increase in the apparent kinetic constants (k(PX) ) for bicarbonate and lactate of two-fold during dobutamine infusion. These data correlate with the double product (rate-pressure product), an indirect parameter of cardiac oxygen...

  6. Real-time radiography

    Bossi, R.H.; Oien, C.T.


    Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.

  7. Real-time Cosmology

    Quercellini, Claudia; Balbi, Amedeo; Cabella, Paolo; Quartin, Miguel


    In recent years the possibility of measuring the temporal change of radial and transverse position of sources in the sky in real time have become conceivable thanks to the thoroughly improved technique applied to new astrometric and spectroscopic experiments, leading to the research domain we call Real-time cosmology. We review for the first time great part of the work done in this field, analysing both the theoretical framework and some endeavor to foresee the observational strategies and their capability to constrain models. We firstly focus on real time measurements of the overall redshift drift and angular separation shift in distant source, able to trace background cosmic expansion and large scale anisotropy, respectively. We then examine the possibility of employing the same kind of observations to probe peculiar and proper acceleration in clustered systems and therefore the gravitational potential. The last two sections are devoted to the short time future change of the cosmic microwave background, as ...

  8. Real-Time Shading

    Olano, Marc


    This book covers real-time shading systems, their design and how they work. Procedural shading, long valued for off-line rendering and production animation is now possible on interactive graphics hardware. These developments are important for areas such as game development, product design, and scientific visualization, among others. The authors include examples of techniques for achieving common effects efficiently in a real-time shading language ranging from full procedural shading on advanced specialized hardware to limited, yet surprisingly flexible shading on unextended OpenGL, to modern P

  9. Real-Time Evaluations



    Full Text Available A real-time evaluation (RTE is a timely, rapid andinteractive review of a fast evolving humanitarianoperation undertaken at an early phase. Its broadobjectives are to gauge the effectiveness and impactof a given UNHCR response and to ensure that itsfindings are used as an immediate catalyst fororganisational and operational change.

  10. Real-Time Three-Dimensional Echocardiography as a Novel Approach to Quantify Left Ventricular Dyssynchrony: A Comparison Study with Phase Analysis of Gated Myocardial Perfusion Single Photon Emission Computed Tomography

    Marsan, Nina Ajmone; Henneman, Maureen M.; Chen, Ji; Ypenburg, Claudia; Dibbets, Petra; Ghio, Stefano; Bleeker, Gabe B.; Stokkel, Marcel P.; van der Wall, Ernst E.; Tavazzi, Luigi; Garcia, Ernest V.; Bax, Jeroen J.


    Background Different imaging modalities have been explored for assessment of left ventricular (LV) dyssynchrony. Gated myocardial perfusion single photon emission computed tomography (GMPS) with phase analysis is a reliable technique to quantify LV dyssynchrony and predict response to cardiac resynchronization therapy. Objective Real-time 3-dimensional echocardiography (RT3DE) is a novel imaging technique that provides a LV systolic dyssynchrony index, based on regional volumetric changes as a function of time and calculated as the SD of time to minimum systolic volume of 16 standard myocardial segments expressed in percentage of cardiac cycle. The aim of this study was to compare LV dyssynchrony evaluated with GMPS with LV dyssynchrony assessed with RT3DE. Methods The study population consisted of 40 patients with heart failure who underwent both GMPS and RT3DE. Results Good correlations between LV dyssynchrony assessed with RT3DE and GMPS were demonstrated (r = 0.76 for histogram bandwidth, r = 0.80 for phase SD, P < .0001). Patients with substantial LV dyssynchrony on GMPS (defined as ≥135 degrees for histogram bandwidth and ≥43 degrees for phase SD) had significantly higher LV systolic dyssynchrony index than patients without substantial LV dyssynchrony. Conclusions The good correlations between LV dyssynchrony assessed with GMPS and with RT3DE provide further support for the use of RT3DE for reliable assessment of LV dyssynchrony. PMID:18222645

  11. Real Time Processing

    CERN. Geneva; ANDERSON, Dustin James; DOGLIONI, Caterina


    The LHC provides experiments with an unprecedented amount of data. Experimental collaborations need to meet storage and computing requirements for the analysis of this data: this is often a limiting factor in the physics program that would be achievable if the whole dataset could be analysed. In this talk, I will describe the strategies adopted by the LHCb, CMS and ATLAS collaborations to overcome these limitations and make the most of LHC data: data parking, data scouting, and real-time analysis.

  12. Real Time Econometrics

    Pesaran, M. Hashem; Timmermann, Allan


    This paper considers the problems facing decision makers using econometric models in real time. It identifies the key stages involved and highlights the role of automated systems in reducing the effect of data snooping. It sets out many choices that researchers face in construction of automated systems and discusses some of the possible ways advanced in the literature for dealing with them. The role of feedbacks from the decision maker?s actions to the data generating process is also discusse...

  13. Use of three-dimensional computed tomography overlay for real-time cryoballoon ablation in atrial fibrillation reduces radiation dose and contrast dye.

    Oude Velthuis, B; Molenaar, M; Reinhart Dorman, H G; Stevenhagen, J Y; Scholten, M F; van der Palen, J; van Opstal, J M


    Cryoballoon pulmonary vein (PV) isolation in patients with atrial fibrillation has proven to be effective in short-term and long-term follow-up. To visualise the PV anatomy, pre-ablation contrast pulmonary venography is commonly performed. Three-dimensional (3D) computed tomography (CT) overlay is a new technique creating a live 3D image of the left atrium by integrating a previously obtained CT scan during fluoroscopy. To evaluate the benefits of 3D CT overlay during cryoballoon ablation, we studied the use of 3D CT overlay versus contrast pulmonary venography in a randomised fashion in patients with paroxysmal atrial fibrillation undergoing cryoballoon PV isolation. Between October 2012 and June 2013, 30 patients accepted for PV isolation were randomised to cryoballoon PV isolation using either 3D CT overlay or contrast pulmonary venography. All patients underwent a pre-procedural cardiac CT for evaluation of the anatomy of the left atrium (LA) and the PVs. In the 3D CT overlay group, a 3D reconstruction of the LA and PVs was made. An overlay of the CT reconstruction was then projected over live fluoroscopy. Patients in the contrast pulmonary venography group received significantly more contrast agent (77.1 ± 21.2 cc vs 40.1 ± 17.6 cc, p overlay group. There was no difference in total procedure time, fluoroscopy time and the amount of cryoapplications between the two groups. The use of 3D CT overlay decreases radiation and contrast dye exposure and can assist in guiding cryoballoon-based PV isolation.

  14. Real time Faraday spectrometer

    Smith, Jr., Tommy E.; Struve, Kenneth W.; Colella, Nicholas J.


    This invention uses a dipole magnet to bend the path of a charged particle beam. As the deflected particles exit the magnet, they are spatially dispersed in the bend-plane of the magnet according to their respective momenta and pass to a plurality of chambers having Faraday probes positioned therein. Both the current and energy distribution of the particles is then determined by the non-intersecting Faraday probes located along the chambers. The Faraday probes are magnetically isolated from each other by thin metal walls of the chambers, effectively providing real time current-versus-energy particle measurements.

  15. Effects of hypoxia on coronary flow reserve as determined by myocardial contrast echocardiography in swine

    YANG Yuan 杨源; LI Shu-qing 李树清; Barry Peters; Anthony N DeMaria


    Background Time-intensity curves derived from microbubble destruction/refilling sequences and recorded using myocardial contrast echocardiography (MCE) can provide parameters that correlate with coronary blood flow. The response of these parameters to adenosine vasodilatation correlates with coronary flow reserve (CFR) measured by fluorescent microsphere techniques (FMT). Currently, no data exist regarding the effect of physiological variables, such as hypoxia, on the determination of CFR by MCE. The purpose of this study was to define the effects of decreases in blood partial pressure of oxygen (PO2) on CFR as measured by MCE. Methods Studies were performed in 9 closed chest swine. Low-energy, real-time MCE was performed with commercial instruments in short axis view at papillary muscle level while infusing BR1 at 30 ml/h. High-energy ultrasound bursts (referred to as FLASH frames) destroyed the bubbles every 15 cardiac cycles, and resultant time-intensity curves derived from these sequences were fitted to the exponential function y = A (1-e-bt) +c, from which the rate of signal rise (b) was obtained. CFR was calculated as the ratio of b values after adenosine infusion to baseline and was obtained during the control period and after decreasing blood PO2 by giving nitrogen via a respirator to create artificial hypoxic conditions. CFR was independently determined by FMT. Results Nitrogen led to significant decreases in mean PO2, from (120.6±18.9) mmHg to (51.8±15.9) mmHg (P0.05 compared with the baseline). Conclusions CFR values diminish under hypoxic conditions according to both MCE and FMT. The reductions in CFR involve both an increase in resting values and a decrease in post adenosine measurements, as determined by both techniques. The reduction in CFR under hypoxia is slightly greater using MCE than using FMT. Physiological variables, such as hypoxia, must be taken into consideration when assessing CFR by MCE.

  16. Correlation between myocardial dysfunction and perfusion impairment in diabetic rats with velocity vector imaging and myocardial contrast echocardiography.

    Wei, Zhangrui; Zhang, Haibin; Su, Haili; Zhu, Ting; Zhu, Yongsheng; Zhang, Jun


    The purpose of this study was to investigate whether myocardial systolic dysfunction and perfusion impairment occur in diabetic rats, and to assess their relationship using velocity vector imaging (VVI) and myocardial contrast echocardiography (MCE). Forty-six rats were randomly divided into either control or the diabetes mellitus (DM) groups. DM was induced by intraperitoneal administration of streptozotocin. Twelve weeks later, 39 survival rats underwent VVI and MCE in short-axis view at the middle level of the left ventricle, both at rest and after dipyridamole stress. VVI-derived contractile parameters included peak systolic velocity (Vs ), circumferential strain (εc ), strain rate (SRc ), and their reserves. MCE-derived perfusion parameters consisted of myocardial blood flow (MBF) and myocardial flow reserve (MFR). At rest, SRc in the DM group was significantly lower than in the control group, Vs , εc , and MBF did not differ significantly between groups. After dipyridamole stress, all VVI parameters and their reserves in the DM group were significantly lower than those in the control group, MBF and MFR were substantially lower than those in the control group, too. Meanwhile, significant correlations between VVI parameter reserves and MFR were observed in the DM group. Both myocardial systolic function and perfusion were impaired in DM rats. Decreased MFR could be an important contributor to the reduction in myocardial contractile reserve.

  17. Contrast-enhanced MRI of murine myocardial infarction - part II

    Coolen, B.F.; Paulis, L.E.M.; Geelen, T.; Nicolay, K.; Strijkers, G.J.


    Mouse models are increasingly used to study the pathophysiology of myocardial infarction in vivo. In this area, MRI has become the gold standard imaging modality, because it combines high spatial and temporal resolution functional imaging with a large variety of methods to generate soft tissue contr

  18. Contrast-enhanced MRI of murine myocardial infarction - part II

    Coolen, B.F.; Paulis, L.E.M.; Geelen, T.; Nicolay, K.; Strijkers, G.J.


    Mouse models are increasingly used to study the pathophysiology of myocardial infarction in vivo. In this area, MRI has become the gold standard imaging modality, because it combines high spatial and temporal resolution functional imaging with a large variety of methods to generate soft tissue

  19. Real time production optimization

    Saputelli, Luigi; Otavio, Joao; Araujo, Turiassu; Escorcia, Alvaro [Halliburton, Houston, TX (United States). Landmark Division


    Production optimization encompasses various activities of measuring, analyzing, modeling, prioritizing and implementing actions to enhance productivity of a field. We present a state-of-the-art framework for optimizing production on a continuous basis as new sensor data is acquired in real time. Permanently acquired data is modeled and analyzed in order to create predictive models. A model based control strategy is used to regulate well and field instrumentation. The optimum field operating point, which changes with time, satisfies the maximum economic return. This work is a starting point for further development in automatic, intelligent reservoir technologies which get the most out of the abilities of permanent, instrumented wells and remotely activated downhole completions. The strategy, tested with history-matched data from a compartmentalised giant field, proved to reduce operating costs while increasing oil recovery by 27% in this field. (author)

  20. Real time production optimization

    Saputelli, Luigi; Otavio, Joao; Araujo, Turiassu; Escorcia, Alvaro [Halliburton, Houston, TX (United States). Landmark Division


    Production optimization encompasses various activities of measuring, analyzing, modeling, prioritizing and implementing actions to enhance productivity of a field. We present a state-of-the-art framework for optimizing production on a continuous basis as new sensor data is acquired in real time. Permanently acquired data is modeled and analyzed in order to create predictive models. A model based control strategy is used to regulate well and field instrumentation. The optimum field operating point, which changes with time, satisfies the maximum economic return. This work is a starting point for further development in automatic, intelligent reservoir technologies which get the most out of the abilities of permanent, instrumented wells and remotely activated downhole completions. The strategy, tested with history-matched data from a compartmentalised giant field, proved to reduce operating costs while increasing oil recovery by 27% in this field. (author)

  1. Magnetic resonance imaging dynamic contrast enhancement (DCE) characteristics of healed myocardial infarction differ from viable myocardium.

    Goldfarb, James W; Zhao, Wenguo


    To determine whether healed myocardial infarction alters dynamic contrast-enhancement (DCE) curve shapes as well as late gadolinium-enhancement (LGE). Twenty patients with chronic myocardial infarction underwent MR imaging at 1.5 T with blood and myocardial T1 measurements before and after contrast administration for forty minutes. Viable and infarcted myocardial partition coefficients were calculated using multipoint slope methods for ten different DCE sampling intervals and windows. Partition coefficients and coefficients of determination were compared with paired statistical tests to assess the linearity of DCE curve shapes over the 40 min time period. Calculated partition coefficients did not vary significantly between methods (p=0.325) for viable myocardium but did differ for infarcted myocardium (pinfarcted DCE. There was a significant difference between viable and infarcted myocardial partition coefficients estimates for all methods with the exception of methods that included measurements during the first 10 min after contrast agent administration. Myocardial partition coefficients calculated from a slope calculation vary in healed myocardial infarction based on the selection of samples due to non-linear DCE curve shapes. Partition coefficient calculations are insensitive to data sampling effects in viable myocardium due to linear DCE curve shapes. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Ovation Prime Real-Time

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ovation Prime Real-Time (OPRT) product is a real-time forecast and nowcast model of auroral power and is an operational implementation of the work by Newell et...

  3. Usefulness of dobutamine stress myocardial contrast echocardiography for assessing coronary artery disease

    GUO Shi-zun; SHU Xian-hong; PAN Cui-zhen; LI Yan-lin; CE Jun-bo; CHEN Hao-zhu


    Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease (CAD), and represents an important goal of myocardial contrast echocardiography. In this study we sought to test the usefulness of low dose dobutamine stress real-time myocardial contrast echocardiography (RT-MCE) in the assessment of CAD, and to explore the relationship between perfusion reserve and contractile reserve.Methods Twenty-six patients with suspected or clinical diagnosed CAD were enrolled and underwent RT-MCE at baseline and under low dose dobutamine stress, and subsequent coronary angiography. RT-MCE images were analyzed quantitatively from microbubble replenishment curves for myocardial perfusion and its reserve. Results At baseline, significant differences in beta (0.28±0.12, 0.25±0.09, 0.22±0.06, 0.20±0.07 respectively, P<0.01) and A×beta (1.37±0.46, 1.28±0.47, 1.13±0.37, 0.91±0.32, respectively, P<0.01) were observed among four segment groups with graded coronary artery stenosis severity (normal; 30%-69% stenosis; 70%-90% stenosis; and beyond 90% stenosis), but not observed in parameter A. When under stress, significant differences in A (5.73±1.28, 5.63±1.01, 4.96±0.81, 4.57±0.62, respectively, P<0.01), beta (0.67±0.17, 0.55±0.19, 0.32±0.13, 0.25±0.08, respectively, P<0.01) and A×beta (3.81±1.20, 3.11±1.17, 1.59±0.82, 1.12±0.37, respectively, P<0.01) were observed among the formerly mentioned groups. Graded decreases in A reserve (1.20±0.53, 1.11±0.16, 0.98±0.12, 0.99±0.13, respectively, P<0.01), beta reserve (2.65±1.07, 2.32±0.82, 1.44±0.40, 1.29±0.34,respectively, P<0.01) and A×beta reserve (3.05±1.63, 2.59±1.01, 1.42±0.44, 1.27±0.34, respectively, P<0.01) could also be observed with increasing coronary stenosis severity. In five segments groups scored by WMS (1-5), concordance between contractile function and

  4. Evaluation and simplified measurement of infarct size by myocardial contrast echocardiography in a rat model of myocardial infarction.

    Chen, Xianghui; Cui, Kai; Xiu, Jiancheng; Lin, Huanbing; Lao, Yi; Zhou, Biying; Liang, Feixue; Zha, Daogang; Bin, Jianping; Liu, Yili


    To test the feasibility and accuracy of myocardial contrast echocardiography (MCE) for predicting infarct size (IS) in a rat model of myocardial infarction (MI) and to compare a simplified single plane-based measurement of IS with the conventional three plane-based approach. Fifty male SD rats underwent left anterior descending artery ligation and were evaluated by MCE 8 h post MI. IS was calculated by the single and three plane-based approaches, compared to that determined by triphenyltetrazolium chloride (TTC) staining method. Simplified single plane-based MCE approach and TTC method showed similar IS values (38.48 +/- 16.80% vs. 35.72 +/- 15.33%, P > 0.05) and presented a favorable positive correlation (r = 0.851, P rats with MI. A single measurement at the mid-papillary muscle level may become a simple, efficient and reliable approach for in vivo IS assessment.

  5. Designing Real Time Assistive Technologies

    Sonne, Tobias; Obel, Carsten; Grønbæk, Kaj


    design criteria in relation to three core components (sensing, recognizing, and assisting) for designing real time assistive technologies for children with ADHD. Based on these design criteria, we designed the Child Activity Sensing and Training Tool (CASTT), a real time assistive prototype that captures...... activities and assists the child in maintaining attention. From a preliminary evaluation of CASTT with 20 children in several schools, we and found that: 1) it is possible to create a wearable sensor system for children with ADHD that monitors physical and physiological activities in real time; and that 2......) real time assistive technologies have potential to assist children with ADHD in regaining attention in critical school situations....

  6. Designing Real Time Assistive Technologies

    Sonne, Tobias; Obel, Carsten; Grønbæk, Kaj

    design criteria in relation to three core components (sensing, recognizing, and assisting) for designing real time assistive technologies for children with ADHD. Based on these design criteria, we designed the Child Activity Sensing and Training Tool (CASTT), a real time assistive prototype that captures...... activities and assists the child in maintaining attention. From a preliminary evaluation of CASTT with 20 children in several schools, we and found that: 1) it is possible to create a wearable sensor system for children with ADHD that monitors physical and physiological activities in real time; and that 2......) real time assistive technologies have potential to assist children with ADHD in regaining attention in critical school situations....

  7. Myocardial delayed contrast enhancement in patients with arterial hypertension: Initial results of cardiac MRI

    Andersen, Kjel [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:; Hennersdorf, Marcus [Department of Cardiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:; Cohnen, Mathias [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:; Blondin, Dirk [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:; Moedder, Ulrich [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:; Poll, Ludger W. [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail:


    Purpose: In arterial hypertension left ventricular hypertrophy comprises myocyte hypertrophy, interstitial fibrosis and structural alterations of the coronary microcirculation. MRI enables the detection of myocardial fibrosis, infarction and scar tissue by delayed enhancement (DE) after contrast media application. Aim of this study was to investigate patients with arterial hypertension but without known coronary disease or previous myocardial infarction to detect areas of DE. Methods and material: Twenty patients with arterial hypertension with clinical symptoms of myocardial ischemia, but without history of myocardial infarction and normal coronary arteries during coronary angiography were investigated on a 1.0 T superconducting magnet (Gyroscan T10-NT, Intera Release 8.0, Philips). Fast gradient-echo cine sequences and T2-weighted STIR-sequences were acquired. Fifteen minutes after injection of Gadobenate dimeglumine inversion recovery gradient-echo sequences were performed for detection of myocardial DE. Presence or absence of DE on MRI was correlated with clinical data and the results of echocardiography and electrocardiography, respectively. Results: Nine of 20 patients showed DE in the interventricular septum and the anteroseptal left ventricular wall. In 6 patients, DE was localized intramurally and in 3 patients subendocardially. There was a significant correlation between myocardial DE and ST-segment depressions during exercise and between DE and left-ventricular enddiastolic pressure. Patients with intermittent atrial fibrillation showed a myocardial DE more often than patients without atrial fibrillation. Conclusion: In our series, 45% of patients with arterial hypertension showed DE on cardiac MRI. In this clinical setting, delayed enhancement may be due to coronary microangiopathy. The more intramurally localization of DE, however, rather indicates myocardial interstitial fibrosis.


    王立清; 胡盛涛; 李澎; 谢峰; 吴清玉; 郭加强


    Objective. To study the mechanism and effects of blood perfusion to the acute ischemic region of myecardium through Ho-YAG laser channels with myocardial contrast echocardiography Methods. To produce the model of acute myocardial ischemia, we partially ligated the left anterior decending (IAD)coromry artery of canine hearts between 1st. and 2nd. diagonal branches and then performed transmyocardial revasmgafizafion in this region with Ho- YAG laser. Myocardial contrast echecardingmphy was made with a new gen-eration of ultrasound contrast agent and second harmonic imaging of this region before,after ischemia and after laser revascalarizafion. Pictures were taken with “R” wave trigger skill. Results. Acoustic demity derterming in the ischemia region (anterior wall)with MCE(myocardial contrast e-checardiography) was obviously decreased(5.40 ± 1.81) after the LAD was ligated,as compared with before( 11.69± 1.61, P 0.05). There were no dif-ferences in acoustic density in the lateral wall(as control)among these comprehensive three periods (P > 0.05). Con-trast in the laser region developed one cardiac cycle ahead of that in the non-iscbemic normal region. Conclusion. Acute ischemic myecardium can be perfused by oxygenated blood from the left ventricle through Ho-YAG laser channels. Evidenee of blood perfusion through laser channels during systolic phase was detected,and my-ocardial cormast ultrasonngtaphy using intravenous perfluorocarbon-exposed sonicated dextrose albumin may be regard-ed as a reliable method in the study of tranmlyecardial revasculariztion.

  9. Real-time volume graphics

    Engel, Klaus; Kniss, Joe; Rezk-Salama, Christof; Weiskopf, Daniel


    Based on course notes of SIGGRAPH course teaching techniques for real-time rendering of volumetric data and effects; covers both applications in scientific visualization and real-time rendering. Starts with the basics (texture-based ray casting) and then improves and expands the algorithms incrementally. Book includes source code, algorithms, diagrams, and rendered graphics.

  10. Repeat Targeted Prostate Biopsy under Guidance of Multiparametric MRI-Correlated Real-Time Contrast-Enhanced Ultrasound for Patients with Previous Negative Biopsy and Elevated Prostate-Specific Antigen: A Prospective Study

    Jang, Dong Ryul; Jung, Dae Chul; Oh, Young Taik; Noh, Songmi; Han, Kyunghwa; Kim, Kiwook; Rha, Koon-Ho; Choi, Young Deuk; Hong, Sung Joon


    Objectives To prospectively determine whether multi-parametric MRI (mpMRI) - contrast-enhanced ultrasound (CEUS) correlated, imaging-guided target biopsy (TB) method could improve the detection of prostate cancer in re-biopsy setting of patients with prior negative biopsy. Methods From 2012 to 2014, a total of 42 Korean men with a negative result from previous systematic biopsy (SB) and elevated prostate-specific antigen underwent 3T mpMRI and real-time CEUS guided TB. Target lesions were determined by fusion of mpMRI and CEUS. Subsequently, 12-core SB was performed by a different radiologist. We compared core-based cancer detection rates (CaDR) using the generalized linear mixed model (GLIMMIX) for each biopsy method. Results Core-based CaDR was higher in TB (17.92%, 38 of 212 cores) than in SB (6.15%, 31 of 504 cores) (p biopsy of patients with prior negative biopsy can improve CaDR based on the number of cores taken. PMID:26083348

  11. Real-time vision systems

    Johnson, R.; Hernandez, J.E.; Lu, Shin-yee [Lawrence Livermore National Lab., CA (United States)


    Many industrial and defence applications require an ability to make instantaneous decisions based on sensor input of a time varying process. Such systems are referred to as `real-time systems` because they process and act on data as it occurs in time. When a vision sensor is used in a real-time system, the processing demands can be quite substantial, with typical data rates of 10-20 million samples per second. A real-time Machine Vision Laboratory (MVL) was established in FY94 to extend our years of experience in developing computer vision algorithms to include the development and implementation of real-time vision systems. The laboratory is equipped with a variety of hardware components, including Datacube image acquisition and processing boards, a Sun workstation, and several different types of CCD cameras, including monochrome and color area cameras and analog and digital line-scan cameras. The equipment is reconfigurable for prototyping different applications. This facility has been used to support several programs at LLNL, including O Division`s Peacemaker and Deadeye Projects as well as the CRADA with the U.S. Textile Industry, CAFE (Computer Aided Fabric Inspection). To date, we have successfully demonstrated several real-time applications: bullet tracking, stereo tracking and ranging, and web inspection. This work has been documented in the ongoing development of a real-time software library.

  12. The enhancement modes of real time contrast-enhanced ultrasound in the breast lesions%乳腺实性病灶实时超声造影增强模式的研究

    李利; 刘淑萍; 汪娜; 姚克纯; 吴迪


    目的:观察超声造影在乳腺实性病灶中的不同增强模式,探讨该技术对乳腺疾病的应用价值.方法:应用SonoVue观察乳腺实性病灶55例,各组别包括腺病25例,纤维腺瘤20例,乳腺癌10例.超声造影增强模式从以下方面评价:①ROI曲线的增强时相及强度;②病灶增强的目视特征;③病灶增强的边界特征.结果:53例病灶均有不同程度的增强,ROI曲线形态显示增强均为快速增强型,各组别增强起始时间及达峰时间无显著差异(P>0.05),腺病组与纤维腺瘤组的峰值强度与增强持续时间高于乳腺癌组(P>0.05).病灶增强的目视特征:80%腺病病灶和95%纤维腺瘤表现为均匀增强型,乳腺癌组均表现为周边增强或不均匀增强.病灶增强的边界特征:70%的纤维腺瘤和80%的乳腺癌病灶表现为边界清晰型,76%的腺病病灶表现为无边界型.结论:乳腺实性病灶的不同增强模式能为乳腺疾病的诊断提供重要的影像学信息.%Objective: To observe the different enhancement modes of breast nodules using real-time contrast enhanced ultrasound and assess its clinical value in the diagnosis of breast lesions. Methods:The nodules included 25 adenosis, 20 fibroadenoma and 10 breast cancer were observed by contrast enhanced sonography using SonoVue. The time-intensity curve, the enhancement patterns and the characteristic of lesion's border were evaluated. Results : 53 cases were enhanced in some degree and all the lesions were fast enhanced on ROI curves. There were no significant difference about the time of initial enhancemcnt and the peak enhancement on each group ( P>0. 05). The peak inrensity and the enhanced duration were higher in fibroadenoma or adenosis than breast cancer ( P <0. 05). About the enhancement vision appearance. 80%adenosis and 95% fibroadenoma were homogeneous and all the malignant lesions were inhomogeneous enhanced or radial enhancement-around lesion. About the lesion

  13. Evaluating real-time forecasts in real-time

    D.J.C. van Dijk (Dick); Ph.H.B.F. Franses (Philip Hans); F. Ravazzolo (Francesco)


    textabstractThe accuracy of real-time forecasts of macroeconomic variables that are subject to revisions may crucially depend on the choice of data used to compare the forecasts against. We put forward a flexible time-varying parameter regression framework to obtain early estimates of the final valu

  14. Towards Real-Time Argumentation

    Vicente JULIÁN


    Full Text Available In this paper, we deal with the problem of real-time coordination with the more general approach of reaching real-time agreements in MAS. Concretely, this work proposes a real-time argumentation framework in an attempt to provide agents with the ability of engaging in argumentative dialogues and come with a solution for their underlying agreement process within a bounded period of time. The framework has been implemented and evaluated in the domain of a customer support application. Concretely, we consider a society of agents that act on behalf of a group of technicians that must solve problems in a Technology Management Centre (TMC within a bounded time. This centre controls every process implicated in the provision of technological and customer support services to private or public organisations by means of a call centre. The contract signed between the TCM and the customer establishes penalties if the specified time is exceeded.

  15. Evaluation of the effect of myocardial perfusion after percutaneous coronary intervention in coronary artery disease by using intracoronary myocardial contrast echocardiography and two other angiographic techniques

    WANG Hong; LIU Zheng; YANG Li; HUANG Lan; JIN Jun; SONG Yaoming; GENG Zhaohua; YU Xuejun; QIN Jun; ZHAO Gang; GAO Yunhua


    Detection of abnormal myocardial perfusion is crucial to the prognosis of patients with coronary artery disease (CAD) after they have undergone percutaneous coronary intervention (PCI).The objective of this study is to evaluate the effect of myocardial perfusion by three different methods-intra-coronary myocardial contrast echocardiography (ICMCE),corrected thrombolysis in myocardial infarction frame count (CTFC),and coronary blood flow velocity (BFV)-and to determine the value of these different methods in the evaluation of the effect of myocardial perfusion post-PCI.For the study sixty-eight patients were divided into four groups based on selective coronary angiography results:group A (normal coronary artery),group B (75%-95% coronary artery stenosis),group C (coronary artery stenosis > 95%) and group D (acute total coronary occlusion).The effect of myocardial reperfusion was evaluated using the above mentioned three methods 15 min after PCI.IC-MCE was also performed before PCI in group D.The quantitative parameters of MCE involved:contrast peak intensity,time to peak intensity and area under the curve,representing myocardial blood volume,reperfusion velocity and myocardial blood flow,respectively.No difference was found in CTFC between the coronary artery stenosis group and the normal group.BFV was slower in group D than in group A (P < 0.05).The myocardial blood volume and the myocardial blood flow of the IC-MCE quantitative parameters were markedly lower in group C compared with those in group A (P < 0.05),and there were significant differences in the three MCE parameters between group D and group A (P < 0.05).For those patients with acute or total occlusion,the levels of myocardial perfusion before and after PCI were similar,as determined by IC-MCE and visually analyzed from 61 segments (P < 0.05).Quantitative IC-MCE evaluation of myocardial reperfusion is more accurate than with the other two methods.Moreover,with qualitative IC-MCE the level of

  16. Real Time Sonic Boom Display

    Haering, Ed


    This presentation will provide general information about sonic boom mitigation technology to the public in order to supply information to potential partners and licensees. The technology is a combination of flight data, atmospheric data and terrain information implemented into a control room real time display for flight planning. This research is currently being performed and as such, any results and conclusions are ongoing.

  17. Real Time Conference 2016 Overview

    Luchetta, Adriano


    This is a special issue of the IEEE Transactions on Nuclear Science containing papers from the invited, oral, and poster presentation of the 20th Real Time Conference (RT2016). The conference was held June 6-10, 2016, at Centro Congressi Padova “A. Luciani,” Padova, Italy, and was organized by Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA) and the Istituto Nazionale di Fisica Nucleare. The Real Time Conference is multidisciplinary and focuses on the latest developments in real-time techniques in high-energy physics, nuclear physics, astrophysics and astroparticle physics, nuclear fusion, medical physics, space instrumentation, nuclear power instrumentation, general radiation instrumentation, and real-time security and safety. Taking place every second year, it is sponsored by the Computer Application in Nuclear and Plasma Sciences technical committee of the IEEE Nuclear and Plasma Sciences Society. RT2016 attracted more than 240 registrants, with a large proportion of young researchers and engineers. It had an attendance of 67 students from many countries.

  18. Real time automatic scene classification

    Israël, Menno; Broek, van den Egon L.; Putten, van der Peter; Uyl, den Marten J.; Verbrugge, R.; Taatgen, N.; Schomaker, L.


    This work has been done as part of the EU VICAR (IST) project and the EU SCOFI project (IAP). The aim of the first project was to develop a real time video indexing classification annotation and retrieval system. For our systems, we have adapted the approach of Picard and Minka [3], who categorized

  19. Decentralized Real-Time Scheduling


    917-932, August, 1987. [ Daniels 86] D. C. Daniels and H. F. Wedde. Real-Time Performance of a Completely Distributed Operating System. In Proceedings...imnmediate execuoon The schedule c.-eated by the SeltctPhaseProcfj procedure is an ordere-d lis t of mocl -phnise pairs, each placed according to the

  20. Real time automatic scene classification

    Verbrugge, R.; Israël, Menno; Taatgen, N.; van den Broek, Egon; van der Putten, Peter; Schomaker, L.; den Uyl, Marten J.


    This work has been done as part of the EU VICAR (IST) project and the EU SCOFI project (IAP). The aim of the first project was to develop a real time video indexing classification annotation and retrieval system. For our systems, we have adapted the approach of Picard and Minka [3], who categorized

  1. ISTTOK real-time architecture

    Carvalho, Ivo S., E-mail:; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Hekkert, Tiago; Carvalho, Bernardo B.


    Highlights: • All real-time diagnostics and actuators were integrated in the same control platform. • A 100 μs control cycle was achieved under the MARTe framework. • Time-windows based control with several event-driven control strategies implemented. • AC discharges with exception handling on iron core flux saturation. • An HTML discharge configuration was developed for configuring the MARTe system. - Abstract: The ISTTOK tokamak was upgraded with a plasma control system based on the Advanced Telecommunications Computing Architecture (ATCA) standard. This control system was designed to improve the discharge stability and to extend the operational space to the alternate plasma current (AC) discharges as part of the ISTTOK scientific program. In order to accomplish these objectives all ISTTOK diagnostics and actuators relevant for real-time operation were integrated in the control system. The control system was programmed in C++ over the Multi-threaded Application Real-Time executor (MARTe) which provides, among other features, a real-time scheduler, an interrupt handler, an intercommunications interface between code blocks and a clearly bounded interface with the external devices. As a complement to the MARTe framework, the BaseLib2 library provides the foundations for the data, code introspection and also a Hypertext Transfer Protocol (HTTP) server service. Taking advantage of the modular nature of MARTe, the algorithms of each diagnostic data processing, discharge timing, context switch, control and actuators output reference generation, run on well-defined blocks of code named Generic Application Module (GAM). This approach allows reusability of the code, simplified simulation, replacement or editing without changing the remaining GAMs. The ISTTOK control system GAMs run sequentially each 100 μs cycle on an Intel{sup ®} Q8200 4-core processor running at 2.33 GHz located in the ATCA crate. Two boards (inside the ATCA crate) with 32 analog

  2. Quantitative myocardial perfusion magnetic resonance imaging: the impact of pulsatile flow on contrast agent bolus dispersion

    Graafen, Dirk; Hamer, Julia; Weber, Stefan; Schreiber, Laura M, E-mail: [Section of Medical Physics, Department of Radiology, Johannes Gutenberg University Medical Center, Mainz (Germany)


    Myocardial blood flow (MBF) can be quantified using T{sub 1}-weighted first-pass magnetic resonance imaging (MRI) in combination with a tracer-kinetic model, like MMID4. This procedure requires the knowledge of an arterial input function which is usually estimated from the left ventricle (LV). Dispersion of the contrast agent bolus may occur between the LV and the tissue of interest. The aim of this study was to investigate the dispersion under conditions of physiological pulsatile blood flow, and to simulate its effect on MBF quantification. The dispersion was simulated in coronary arteries using a computational fluid dynamics (CFD) approach. Simulations were accomplished on straight vessels with stenosis of different degrees and shapes. The results show that dispersion is more pronounced under resting conditions than during hyperemia. Stenosis leads to a reduction of dispersion. In consequence, dispersion results in a systematic MBF underestimation between -0.4% and -9.3%. The relative MBF error depends not only on the dispersion but also on the actual MBF itself. Since MBF under rest is more underestimated than under stress, myocardial perfusion reserve is overestimated between 0.1% and 4.5%. Considering other sources of errors in myocardial perfusion MRI, systematic errors of MBF by bolus dispersion are relatively small.

  3. Radiation damping in real time.

    Mendes, A C; Takakura, F I


    We study the nonequilibrium dynamics of a charge interacting with its own radiation, which originates the radiation damping. The real-time equation of motion for the charge and the associated Langevin equation is found in classical limit. The equation of motion for the charge allows one to obtain the frequency-dependent coefficient of friction. In the lowest order we find that although the coefficient of static friction vanishes, there is dynamical dissipation represented by a non-Markovian dissipative kernel.

  4. The VLT Real Time Display

    Herlin, T.; Brighton, A.; Biereichel, P.

    The VLT Real-Time Display (RTD) software was developed in order to support image display in real-time, providing a tool for users to display video like images from a camera or detector as fast as possible on an X-Server. The RTD software is implemented as a package providing a Tcl/Tk image widget written in C++ and an independent image handling library and can be used as a building block, adding display capabilities to dedicated VLT control applications. The RTD widget provides basic image display functionality like: panning, zooming, color scaling, colormaps, intensity changes, pixel query, overlaying of line graphics. A large set of assisting widgets, e.g., colorbar, zoom window, spectrum plot are provided to enable the building of image applications. The support for real-time is provided by an RTD image event mechanism used for camera or detector subsystems to pass images to the RTD widget. Image data are passed efficiently via shared memory. This paper describes the architecture of the RTD software and summarizes the features provided by RTD.

  5. Myocardial physiology measurements using contrast enhanced dynamic computed tomography: simulation of beam hardening effect

    Cao, Minsong; Stantz, Keith M.; Liang, Yun


    Initial animal study for quantifying myocardial physiology through contrast-enhanced dynamic x-ray CT suggested that beam hardening is one of the limiting factors for accurate regional physiology measurement. In this study, a series of simulations were performed to investigate its deterioration effects and two correction algorithms were adapted to evaluate for their efficiency in improving the measurements. The simulation tool consists of a module simulating data acquisition of a real polyenergetic scanner system and a heart phantom consisting of simple geometric objects representing ventricles and myocardium. Each phantom component was modeled with time-varying attenuation coefficients determined by ideal iodine contrast dynamic curves obtained from experimental data or simulation. A compartment model was used to generate the ideal myocardium contrast curve using physiological parameters consistent with measured values. Projection data of the phantom were simulated and reconstructed to produce a sequence of simulated CT images. Simulated contrast dynamic curves were fitted to the compartmental model and the resultant physiological parameters were compared with ideal values to estimate the errors induced by beam hardening artifacts. The simulations yielded similar deterioration patterns of contrast dynamic curves as observed in the initial study. Significant underestimation of left ventricle curves and corruption of regional myocardium curves result in systematic errors of regional perfusion up to approximately 24% and overestimates of fractional blood volume (f iv) up to 13%. The correction algorithms lead to significant improvement with errors of perfusion reduced to 7% and errors of f iv within 2% which shows promise for more robust myocardial physiology measurement.

  6. Myocardial contrast echocardiography to assess perfusion in a mouse model of ischemia/reperfusion injury

    Hossack, John A.; Li, Yinbo; Christensen, Jonathan P.; Yang, Zequan; French, Brent A.


    Noninvasive approaches for measuring anatomical and physiological changes resulting from myocardial ischemia / reperfusion injury in the mouse heart have significant value since the mouse provides a practical, low-cost model for modeling human heart disease. In this work, perfusion was assessed before, during and after an induced closed- chest, coronary ischemic event. Ultrasound contrast agent, similar to MP1950, in a saline suspension, was injected via cannulated carotid artery as a bolus and imaged using a Siemens Sequoia 512 scanner and a 15L8 intraoperative transducer operating in second harmonic imaging mode. Image sequences were transferred from the scanner to a PC for analysis. Regions of interest were defined in septal and anterior segments of the myocardium. During the ischemic event, when perfusion was diminished in the anterior segment, mean video intensity in the affected segment was reduced by one half. Furthermore, following reperfusion, hyperemia (enhanced blood flow) was observed in the anterior segment. Specifically, the mean video intensity in the affected segment was increased by approximately 50% over the original baseline level prior to ischemia. Following the approach of Kaul et al., [1], gamma variate curves were fitted to the time varying level of mean video intensity. This foundation suggests the possibility of quantifying myocardial blood flow in ischemic regions of a mouse heart using automated analysis of contrast image data sets. An improved approach to perfusion assessment using the destruction-reperfusion approach [2] is also presented.

  7. Magnetic resonance imaging of microvascular leakage induced by myocardial contrast echocardiography in rats.

    Swanson, Scott D; Dou, Chunyan; Miller, Douglas L


    The extent and magnitude of microvascular leakage induced by myocardial contrast echocardiography (MCE) were characterized with contrast-aided magnetic resonance imaging (MRI). Evans blue dye, Definity ultrasound contrast agent and Omniscan magnetic resonance contrast agent were injected intravenously in anesthetized rats suspended in a water bath. Diagnostic ultrasound B mode scans with 1:4 end-systolic triggering were performed at 1.5 MHz using a cardiac phased array scanhead to provide a short axis view of the left ventricle. The in situ peak rarefactional pressure amplitude (PRPA) was 2.0 MPa. Microvascular leakage was characterized by extraction of the dye from tissue samples and by imaging the distribution and concentration of Omniscan within the myocardium. The extracted Evans blue was 2.3 times greater than in shams (Prats (after sacrifice). These results demonstrate a potential for MR mapping of capillary leakage induced by contrast-aided ultrasound, with a possible application to spatial characterization of local drug delivery.

  8. Real-time streamflow conditions

    Graczyk, David J.; Gebert, Warren A.


    Would you like to know streamflow conditions before you go fishing in Wisconsin or in more distant locations? Real-time streamflow data throughout Wisconsin and the United States are available on the Internet from the U.S. Geological Survey. You can see if the stream you are interested in fishing is high due to recent rain or low because of an extended dry spell. Flow conditions at more than 100 stream-gaging stations located throughout Wisconsin can be viewed by accessing the Wisconsin District Home Page at:

  9. Real-time flutter analysis

    Walker, R.; Gupta, N.


    The important algorithm issues necessary to achieve a real time flutter monitoring system; namely, the guidelines for choosing appropriate model forms, reduction of the parameter convergence transient, handling multiple modes, the effect of over parameterization, and estimate accuracy predictions, both online and for experiment design are addressed. An approach for efficiently computing continuous-time flutter parameter Cramer-Rao estimate error bounds were developed. This enables a convincing comparison of theoretical and simulation results, as well as offline studies in preparation for a flight test. Theoretical predictions, simulation and flight test results from the NASA Drones for Aerodynamic and Structural Test (DAST) Program are compared.

  10. Real time analysis under EDS

    Schneberk, D.


    This paper describes the analysis component of the Enrichment Diagnostic System (EDS) developed for the Atomic Vapor Laser Isotope Separation Program (AVLIS) at Lawrence Livermore National Laboratory (LLNL). Four different types of analysis are performed on data acquired through EDS: (1) absorption spectroscopy on laser-generated spectral lines, (2) mass spectrometer analysis, (3) general purpose waveform analysis, and (4) separation performance calculations. The information produced from this data includes: measures of particle density and velocity, partial pressures of residual gases, and overall measures of isotope enrichment. The analysis component supports a variety of real-time modeling tasks, a means for broadcasting data to other nodes, and a great degree of flexibility for tailoring computations to the exact needs of the process. A particular data base structure and program flow is common to all types of analysis. Key elements of the analysis component are: (1) a fast access data base which can configure all types of analysis, (2) a selected set of analysis routines, (3) a general purpose data manipulation and graphics package for the results of real time analysis. Each of these components are described with an emphasis upon how each contributes to overall system capability. 3 figs.

  11. Real-time analysis keratometer

    Adachi, Iwao P. (Inventor); Adachi, Yoshifumi (Inventor); Frazer, Robert E. (Inventor)


    A computer assisted keratometer in which a fiducial line pattern reticle illuminated by CW or pulsed laser light is projected on a corneal surface through lenses, a prismoidal beamsplitter quarterwave plate, and objective optics. The reticle surface is curved as a conjugate of an ideal corneal curvature. The fiducial image reflected from the cornea undergoes a polarization shift through the quarterwave plate and beamsplitter whereby the projected and reflected beams are separated and directed orthogonally. The reflected beam fiducial pattern forms a moire pattern with a replica of the first recticle. This moire pattern contains transverse aberration due to differences in curvature between the cornea and the ideal corneal curvature. The moire pattern is analyzed in real time by computer which displays either the CW moire pattern or a pulsed mode analysis of the transverse aberration of the cornea under observation, in real time. With the eye focused on a plurality of fixation points in succession, a survey of the entire corneal topography is made and a contour map or three dimensional plot of the cornea can be made as a computer readout in addition to corneal radius and refractive power analysis.

  12. Autonomous Real Time Requirements Tracing

    Plattsmier, George; Stetson, Howard


    One of the more challenging aspects of software development is the ability to verify and validate the functional software requirements dictated by the Software Requirements Specification (SRS) and the Software Detail Design (SDD). Insuring the software has achieved the intended requirements is the responsibility of the Software Quality team and the Software Test team. The utilization of Timeliner-TLX(sup TM) Auto- Procedures for relocating ground operations positions to ISS automated on-board operations has begun the transition that would be required for manned deep space missions with minimal crew requirements. This transition also moves the auto-procedures from the procedure realm into the flight software arena and as such the operational requirements and testing will be more structured and rigorous. The autoprocedures would be required to meet NASA software standards as specified in the Software Safety Standard (NASASTD- 8719), the Software Engineering Requirements (NPR 7150), the Software Assurance Standard (NASA-STD-8739) and also the Human Rating Requirements (NPR-8705). The Autonomous Fluid Transfer System (AFTS) test-bed utilizes the Timeliner-TLX(sup TM) Language for development of autonomous command and control software. The Timeliner-TLX(sup TM) system has the unique feature of providing the current line of the statement in execution during real-time execution of the software. The feature of execution line number internal reporting unlocks the capability of monitoring the execution autonomously by use of a companion Timeliner-TLX(sup TM) sequence as the line number reporting is embedded inside the Timeliner-TLX(sup TM) execution engine. This negates I/O processing of this type data as the line number status of executing sequences is built-in as a function reference. This paper will outline the design and capabilities of the AFTS Autonomous Requirements Tracker, which traces and logs SRS requirements as they are being met during real-time execution of the

  13. Real-time flood forecasting

    Lai, C.; Tsay, T.-K.; Chien, C.-H.; Wu, I.-L.


    Researchers at the Hydroinformatic Research and Development Team (HIRDT) of the National Taiwan University undertook a project to create a real time flood forecasting model, with an aim to predict the current in the Tamsui River Basin. The model was designed based on deterministic approach with mathematic modeling of complex phenomenon, and specific parameter values operated to produce a discrete result. The project also devised a rainfall-stage model that relates the rate of rainfall upland directly to the change of the state of river, and is further related to another typhoon-rainfall model. The geographic information system (GIS) data, based on precise contour model of the terrain, estimate the regions that were perilous to flooding. The HIRDT, in response to the project's progress, also devoted their application of a deterministic model to unsteady flow of thermodynamics to help predict river authorities issue timely warnings and take other emergency measures.


    Yash Sakaria


    Full Text Available On a business level, everyone wants to get hold of the business value and other organizational advantages that big data has to offer. Analytics has arisen as the primitive path to business value from big data. Hadoop is not just a storage platform for big data; it’s also a computational and processing platform for business analytics. Hadoop is, however, unsuccessful in fulfilling business requirements when it comes to live data streaming. The initial architecture of Apache Hadoop did not solve the problem of live stream data mining. In summary, the traditional approach of big data being co-relational to Hadoop is false; focus needs to be given on business value as well. Data Warehousing, Hadoop and stream processing complement each other very well. In this paper, we have tried reviewing a few frameworks and products which use real time data streaming by providing modifications to Hadoop.

  15. Left ventricular layer function in hypertension assessed by myocardial strain rate using novel one-beat real-time three-dimensional speckle tracking echocardiography with high volume rates.

    Saeki, Maki; Sato, Noriaki; Kawasaki, Masanori; Tanaka, Ryuhei; Nagaya, Maki; Watanabe, Takatomo; Ono, Koji; Noda, Toshiyuki; Zile, Michael R; Minatoguchi, Shinya


    We recently developed novel software to measure phasic strain rate (SR) using automated one-beat real-time three-dimensional speckle tracking echocardiography (3D-STE) with high volume rates. We tested the hypothesis that left ventricular (LV) systolic function and relaxation analyzed by SR with the novel 3D-STE in hypertension (HTN) with hypertrophy may be impaired in the endocardium before there is LV systolic dysfunction. We measured LV longitudinal, radial and circumferential SR in patients with HTN (n=80, 69±7 years) and age-matched normotensive controls (n= 60, 69±10 years) using 3D-STE. HTN patients were divided into four groups according to LV geometry: normal, concentric remodeling, concentric hypertrophy and eccentric hypertrophy. We measured SR during systole as an index of systolic function, SR during isovolumic relaxation (IVR) as an index of relaxation and E/e' as an index of filling pressure. Endocardial SR during systole in HTN with concentric and eccentric hypertrophy decreased compared with that in controls despite no reduction in ejection fraction or epicardial SR. Endocardial radial SR during IVR decreased even in normal geometry, and it was further reduced in concentric remodeling and hypertrophy despite no reduction in epicardial SR. LV phasic SR assessed by 3D-STE with high volume rates is a useful index to detect early decreases in LV systolic function and to predict subclinical LV layer dysfunction in patients with HTN.

  16. Clinical virology in real time.

    Niesters, Hubert G M


    The ability to detect nucleic acids has had and still has a major impact on diagnostics in clinical virology. Both quantitative and qualitative techniques, whether signal or target amplification based systems, are currently used routinely in most if not all virology laboratories. Technological improvements, from automated sample isolation to real time amplification technology, have given the ability to develop and introduce systems for most viruses of clinical interest, and to obtain clinical relevant information needed for optimal antiviral treatment options. Both polymerase chain reaction (PCR) and nucleic acid sequence-based amplification (NASBA) can currently be used together with real time detection to generate results in a short turn-around time and to determine whether variants relevant for antiviral resistance are present. These new technologies enable the introduction of an individual patient disease management concept. Within our clinical setting, we have introduced this e.g. for quantitative detection of Epstein-Barr Virus (EBV) in T-dell depleted allogeneic stem cell transplant patients. This enabled us to develop models for pre-emptive anti B-cell immunotherapy for EBV reactivation, thereby effectively reducing not the incidence of EBV-lymphoproliferative disease but the virus related mortality. Furthermore, additional clinically relevant viruses can now easily be detected simultaneously. It also becomes more feasible to introduce molecular testing for those viruses that can easily be detected using classical virological methods, like culture techniques or antigen detection. Prospective studies are needed to evaluate the clinical importance of the additional positive samples detected. It should however be made clear that a complete exchange of technologies is unlikely to occur, and that some complementary technologies should stay operational enabling the discovery of new viruses. The implementation of these molecular diagnostic technologies furthermore

  17. Real-time applications of neural nets

    Spencer, J.E.


    Producing, accelerating and colliding very high power, low emittance beams for long periods is a formidable problem in real-time control. As energy has grown exponentially in time so has the complexity of the machines and their control systems. Similar growth rates have occurred in many areas, e.g., improved integrated circuits have been paid for with comparable increases in complexity. However, in this case, reliability, capability and cost have improved due to reduced size, high production and increased integration which allow various kinds of feedback. In contrast, most large complex systems (LCS) are perceived to lack such possibilities because only one copy is made. Neural nets, as a metaphor for LCS, suggest ways to circumvent such limitations. It is argued that they are logically equivalent to multi-loop feedback/forward control of faulty systems. While complimentary to AI, they mesh nicely with characteristics desired for real-time systems. Such issues are considered, examples given and possibilities discussed. 21 refs., 6 figs.

  18. Mobile real time radiography system

    Vigil, J.; Taggart, D.; Betts, S. [Los Alamos National Lab., NM (United States)] [and others


    A 450-keV Mobile Real Time Radiography (RTR) System was delivered to Los Alamos National Laboratory (LANL) in January 1996. It was purchased to inspect containers of radioactive waste produced at (LANL). Since its delivery it has been used to radiograph more than 600 drums of radioactive waste at various LANL sites. It has the capability of inspecting waste containers of various sizes from <1-gal. buckets up to standard waste boxes (SWB, dimensions 54.5 in. x 71 in. x 37 in.). It has three independent x-ray acquisition formats. The primary system used is a 12- in. image intensifier, the second is a 36-in. linear diode array (LDA) and the last is an open system. It is fully self contained with on board generator, HVAC, and a fire suppression system. It is on a 53-ft long x 8-ft. wide x 14-ft. high trailer that can be moved over any highway requiring only an easily obtainable overweight permit because it weights {approximately}38 tons. It was built to conform to industry standards for a cabinet system which does not require an exclusion zone. The fact that this unit is mobile has allowed us to operate where the waste is stored, rather than having to move the waste to a fixed facility.

  19. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    Nielsen, Gitte; Fritz-Hansen, Thomas; Dirks, Christina G


    with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five...

  20. Gender differences in contrast-enhanced magnetic resonance imaging after acute myocardial infarction.

    Langhans, Birgit; Ibrahim, Tareq; Hausleiter, Jörg; Sonne, Carolin; Martinoff, Stefan; Schömig, Albert; Hadamitzky, Martin


    Besides different risk profiles for cardiovascular events in men and women, several studies reported gender differences in mortality after acute myocardial infarction (AMI). As infarct size has been shown to correlate with mortality, it is widely accepted as surrogate marker for clinical outcome. Currently, cardiovascular imaging studies covering the issue of gender differences are rare. As magnetic resonance scar characterization parameters are emerging as additional prognostic factors after acute myocardial infarction, we sought to evaluate gender differences in CMR infarct characteristics in patients after acute myocardial infarction. We prospectively analyzed patients (n = 448) with AMI and primary angioplasty, who underwent contrast-enhanced cardiac magnetic resonance (CMR) imaging on a 1.5 T scanner in median 5 [4, 6] days after the acute event. [corrected]. CMR scar size was measured 15 min after gadolinium injection. In addition presence and extent of microvascular obstruction (MVO) was assessed. A matched pair analysis was performed in order to exclude confounding by gender related co-morbidities and gender differences in established clinical risk factors. Matching process according to clinical risk defined by GRACE score resulted in 93 mixed gender couples. Women were significantly older than men (64.4 ± 11.9 vs. 60.5 ± 12.3, p = 0.03) and presented with a significantly better ejection fraction before angioplasty (48.9 ± 8.4 vs. 46.2 ± 8.9, p = 0.04). Infarct size did not differ significantly between women and men (13.5 ± 10.7 vs. 15.1 ± 11.8, p = 0.32). Size of MVO was significantly smaller in women than in men (0.48 ± 1.3 vs. 1.2 ± 3.0, p = 0.03). Comparing scar characterization between women and men with similar risk profiles revealed no gender differences in scar size. Size of MVO, however, was significantly smaller in women and might reflect better cardioprotective mechanisms in women. Whether these changes have prognostic implications has to

  1. Telmisartan in the diabetic murine model of acute myocardial infarction: dual contrast manganese-enhanced and delayed enhancement MRI evaluation of the peri-infarct region.

    Toma, Ildiko; Kim, Paul J; Dash, Rajesh; McConnell, Michael V; Nishimura, Dwight; Harnish, Phillip; Yang, Phillip C


    A novel MRI technique, employing dual contrast manganese-enhanced MRI (MEMRI) and delayed enhancement MRI (DEMRI), can evaluate the physiologically unstable peri-infarct region. Dual contrast MEMRI-DEMRI enables comprehensive evaluation of telmisartan to salvage the peri-infarct injury to elucidate the underlying mechanism of restoring the ischemic cardiomyopathy in the diabetic mouse model. Dual contrast MEMRI-DEMRI was performed on weeks 1, 2, and 4 following initiation of telmisartan treatment in 24 left anterior descendent artery ligated diabetic mice. The MRI images were analyzed for core infarct, peri-infarct, left ventricular end-diastolic, end-systolic volumes, and the left ventricular ejection fraction (LVEF). Transmission electron microscopy (TEM) and real-time PCR were used for ex vivo analysis of the myocardium. Telmisartan vs. control groups demonstrated significantly improved LVEF at weeks 1, 2, and 4, respectively (33 ± 7 %*** vs. 19 ± 5 %, 29 ± 3 %*** vs. 22 ± 4 %, and 31 ± 2 %*** vs 18 ± 6 %, ***p Telmisartan group significantly salvaged the peri-infarct injury. The myocardial effects were validated by TEM, which confirmed the presence of the injured but viable cardiomyocyte morphology in the peri-infarct region and by flow cytometry of venous blood, which demonstrated significantly increased circulating endothelial progenitor cells (EPCs). The improved cardiac function in ischemic cardiomyopathy of diabetic mice by telmisartan is attributed to the attenuation of the peri-infarct injury by the angiogenic effects of EPCs to salvage the injured cardiomyocytes. Dual-contrast MEMRI-DEMRI technique tracked the therapeutic effects of telmisartan on the injured myocardium longitudinally.

  2. Computational Fluid Dynamics Simulations of Contrast Agent Bolus Dispersion in a Coronary Bifurcation: Impact on MRI-Based Quantification of Myocardial Perfusion

    Regine Schmidt; Dirk Graafen; Stefan Weber; Schreiber, Laura M.


    Contrast-enhanced first-pass magnetic resonance imaging (MRI) in combination with a tracer kinetic model, for example, MMID4, can be used to determine myocardial blood flow (MBF) and myocardial perfusion reserve (MPR). Typically, the arterial input function (AIF) required for this methodology is estimated from the left ventricle (LV). Dispersion of the contrast agent bolus might occur between the LV and the myocardial tissue. Negligence of bolus dispersion could cause an error in MBF determin...

  3. Students Collecting Real time Data

    Miller, P.


    Students Collecting Real-Time Data The Hawaiian Islands Humpback Whale National Marine Sanctuary has created opportunities for middle and high school students to become Student Researchers and to be involved in real-time marine data collection. It is important that we expose students to different fields of science and encourage them to enter scientific fields of study. The Humpback Whale Sanctuary has an education visitor center in Kihei, Maui. Located right on the beach, the site has become a living classroom facility. There is a traditional Hawaiian fishpond fronting the property. The fishpond wall is being restored, using traditional methods. The site has the incredible opportunity of incorporating Hawaiian cultural practices with scientific studies. The Sanctuary offers opportunities for students to get involved in monitoring and data collection studies. Invasive Seaweed Study: Students are collecting data on invasive seaweed for the University of Hawaii. They pull a large net through the shallow waters. Seaweed is sorted, identified and weighed. The invasive seaweeds are removed. The data is recorded and sent to UH. Remote controlled monitoring boats: The sanctuary has 6 boogie board sized remote controlled boats used to monitor reefs. Boats have a camera with lights on the underside. The boats have water quality monitoring devices and GPS units. The video from the underwater camera is transmitted via a wireless transmission. Students are able to monitor the fish, limu and invertebrate populations on the reef and collect water quality data via television monitors or computers. The boat can also pull a small plankton tow net. Data is being compiled into data bases. Artificial Reef Modules: The Sanctuary has a scientific permit from the state to build and deploy artificial reef modules. High school students are designing and building modules. These are deployed out in the Fishpond fronting the Sanctuary site and students are monitoring them on a weekly basis

  4. Regional contrast agent quantification in a mouse model of myocardial infarction using 3D cardiac T1 mapping

    Nicolay Klaas


    Full Text Available Abstract Background Quantitative relaxation time measurements by cardiovascular magnetic resonance (CMR are of paramount importance in contrast-enhanced studies of experimental myocardial infarction. First, compared to qualitative measurements based on signal intensity changes, they are less sensitive to specific parameter choices, thereby allowing for better comparison between different studies or during longitudinal studies. Secondly, T1 measurements may allow for quantification of local contrast agent concentrations. In this study, a recently developed 3D T1 mapping technique was applied in a mouse model of myocardial infarction to measure differences in myocardial T1 before and after injection of a liposomal contrast agent. This was then used to assess the concentration of accumulated contrast agent. Materials and methods Myocardial ischemia/reperfusion injury was induced in 8 mice by transient ligation of the LAD coronary artery. Baseline quantitative T1 maps were made at day 1 after surgery, followed by injection of a Gd-based liposomal contrast agent. Five mice served as control group, which followed the same protocol without initial surgery. Twenty-four hours post-injection, a second T1 measurement was performed. Local ΔR1 values were compared with regional wall thickening determined by functional cine CMR and correlated to ex vivo Gd concentrations determined by ICP-MS. Results Compared to control values, pre-contrast T1 of infarcted myocardium was slightly elevated, whereas T1 of remote myocardium did not significantly differ. Twenty-four hours post-contrast injection, high ΔR1 values were found in regions with low wall thickening values. However, compared to remote tissue (wall thickening > 45%, ΔR1 was only significantly higher in severe infarcted tissue (wall thickening r = 0.81 was found between CMR-based ΔR1 values and Gd concentrations from ex vivo ICP-MS measurements. Furthermore, regression analysis revealed that the

  5. Contrast-induced nephropathy in postmenopausal women undergoing percutaneous coronary intervention for acute myocardial infarction.

    Ma, Guizhou; Yu, Danqing; Cai, Zhixiong; Ni, Chumin; Xu, Ronghe; Lan, Bin; Chen, Ping; Zhu, Zhidan


    Contrast-induced nephropathy (CIN) is a complex syndrome of acute kidney injury induced by exposure to intravascular contrast media. CIN occurs frequently in patients undergoing urgent percutaneous coronary intervention (PCI) and is associated with poor outcomes, making it a major challenge faced by interventional cardiologists. It has been suggested that female sex is a risk factor for development of CIN following PCI. However, no data exist in the literature concerning the risks of postmenopausal women with acute myocardial infarction (AMI) developing CIN after undergoing urgent PCI. To explore the incidence, risk factors and in-hospital outcomes of CIN in this special population, we analyzed 69 postmenopausal women with AMI treated with urgent PCI. CIN was defined as a relative increase of >25% or an absolute increase of >or=0.5 mg/dL in serum creatinine concentration from the baseline value 72 h after exposure to contrast medium. We found 1) the incidence of CIN was 37.68%; 2) patients with CIN had worse in-hospital outcomes, including longer hospital stay and more in-hospital adverse events; and 3) in multivariate logistic analysis, independent risk factors for CIN included a longer menopausal duration and the implantation of an intra-aortic balloon pump (an indirect indicator of hemodynamic instability). These results indicate that CIN is a frequent complication associated with worse in-hospital outcomes in postmenopausal women with AMI who are undergoing urgent PCI, particularly those with longer menopausal duration and hemodynamic instability. It is therefore necessary to pay more attention to preventive strategies for renal protection in this special population.

  6. Time-efficient myocardial contrast partition coefficient measurement from early enhancement with magnetic resonance imaging.

    Shi-Jun Zhang

    Full Text Available OBJECTIVE: Our purpose was to validate an early enhancement time point for accurately measuring the myocardial contrast partition coefficient (lambda using dynamic-equilibrium magnetic resonance imaging. MATERIALS AND METHODS: The pre- and post-contrast longitudinal relaxation rates (reciprocal of T1 of the interventricular septum (R1(m and blood pool (R1(b were obtained from fifteen healthy volunteers and three diabetic patients with hypertension using two optimized T1 mapping sequences (modified Look-Locker inversion recovery on a 3-Tesla magnetic resonance scanner. Reference lambda values were calculated as the slope of the regression line of R1(m versus R1(b at dynamic equilibrium (multi-point regression method. The simplified pre-/post-enhancement two-acquisition method (two-point method was used to calculate lambda by relating the change in R1(m and R1(b using different protocols according to the acquisition stage of the post-enhancement data point. The agreement with the referential method was tested by calculating Pearson's correlation coefficient and the intra-class correlation coefficient. RESULTS: The lambda values measured by the two-point method increased (from 0.479 ± 0.041 to 0.534 ± 0.043 over time from 6 to 45 minutes after contrast and exhibited good correlation with the reference at each time point (r ≥ 0.875, p<0.05. The intra-class correlation coefficient on absolute agreement with the reference lambda was 0.946, 0.929 and 0.922 at the 6th, 7th and 8th minutes and dropped from 0.878 to 0.403 from the 9th minute on. CONCLUSIONS: The time-efficient two-point method at 6-8 minutes after the Gd-DTPA bolus injection exhibited good agreement with the multi-point regression method and can be applied for accurate lambda measurement in normal myocardium.

  7. Assessment of cardiac function by magnetic resonance imaging: segmented versus real time steady-state free precession sequences

    Bezerra, Leonardo Bernardo [Rio Grande do Norte Univ., Natal, RN (Brazil)]. E-mail:; Marchiori, Edson; Pontes, Paulo V. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia


    Objective: to compare ventricular systolic parameters on segmented and real-time steady-state free precession cine-MRI sequences and ECG-gated MRI in patients presenting or not with cardiac arrhythmias. Materials and methods: ejection fraction and end-diastolic/end-systolic volumes have been compared in 31 patients, 11 presenting with cardiac arrhythmias, and 20 with regular sinus rhythm, using ECG-gated segmented and real-time sequences. The statistical analysis was performed using Pearson's correlation and Bland-Altman agreement plot, with p < 0.01. Results: real-time acquisitions demonstrated endocardial borders blurring effects, but both sequences presented a clear, positive correlation: ejection fraction r = 0.94; end-diastolic volume r = 0.93 and end-systolic volume r 0.98. The assessment of 11 patients with arrhythmias has not demonstrated a statistically significant difference, despite the lower blood pool-myocardial contrast ratio. Conclusion: real-time sequences may be utilized for cardiac function assessment, regardless the patient's cardiac rhythm. (author)

  8. Real Time PCR: Principles and Application

    Safie Amini


    samples and is easy to automate. The reduced number of handling steps results in high reproducibility from sample to sample and minimizes the risk of contamination since less manipulation is required. The advantages of each method are given below(11, 12.DNA as Template in Real-time PCRIn contrast with RNA, which requires conversion into cDNA, purified genomic DNA or plasmid DNA can be directly used as starting template in real-time PCR. Not only can genomic DNA be quantified in real-time PCR, for example, in detection of bacterial DNA, but it can also be used for qualitative analysis, such as single nucleotide polymorphism (SNP detection. SNP analysis involves the detection of single nucleotide changes using two probes labeled with different fluorophores. One probe is specific for the wild-type allele, the other for the mutant allele. Real-time PCR is highly suited for the detection of small sequence differences, such as SNPs and viral variants(13, 14, 15.Quantification of Target AmountsWith PCR, minute amounts of starting template DNA or cDNA can be amplified enabling detection of a target sequence. If PCR products are analyzed by endpoint analysis, quantification is not possible as most reactions will already have reached the plateau phase of amplification. During this phase, no significant increase in PCR product amount takes place. This is mainly due to depletion of PCR components and renaturation of PCR product strands caused by the high concentration of end products, which prevents further primer annealing. If identical template amounts are used, this may not necessarily result in identical yields of PCR products. Equally, if different amounts of template are used, the yield of PCR products may be similar making quantification impossible. Real-time PCR overcomes this problem by determining the actual amount of PCR product present at a given cycle, indicated by the intensity of fluorescence(16, 17.QuantificationTarget nucleic acids can be quantified using either


    王立清; 胡盛寿; 李澎; 谢峰; 吴清玉; 郭加强


    Objective. To study the mechanism and effects of blood perfusion to the acute ischemic region of myocardium through Ho-YAG laser channels with myocardial contrast echocardiography. Methods. To produce the model of acute myocardial ischemia, we partially ligated the left anterior decending (LAD)coronary artery of canine hearts between lst. and 2nd. diagonal branches and then performed transmyocardial revascularization in this region with Ho- YAG laser. Myocardial contrast echocardiography was made with a new gen eration of ultrasound contrast agent and second harmonic imaging of this region before, after ischemia and after laser revascularization. Pictures were taken with “R” wave trigger skill. Results. Acoustic density derterming in the ischemia region (anterior wall)with MCE (myocardial contrast e chocardiography )was obviously decreased( 5.40 ± 1.81) after the LAD was ligated, as compared with before( 11.69 ± 1.61, P < 0.01 ). It was increased remarkably after transmyocardial laser revascularizatuon (TMLR) ( 11.2 ± 2.01, P < 0. 01 )as compared with that when ischemia and approximated to that before ischemia(P > 0.05). There were no dif ferences in acoustic density in the lateral wall(as control)among these comprehensive three periods(P > 0.05). Con trast in the laser region developed one cardiac cycle ahead of that in the non-ischemic normal region. Conclusion. Acute ischemic myocardium can be peffused by oxygenated blood from the left ventricle through Ho YAG laser channels. Evidence of blood perfusion through laser channels during systolic phase was detected, and my ocardial contrast ultrasonography using intravenous perfluorocarbon-exposed sonicated dextrose albumin may be regard ed as a reliable method in the study of transmyocardial revascularization.

  10. Real Time Recognition of Heart Attack in a Smart Phone.

    Rad, Mahshid Zomorodi; Ghuchani, Saeed Rahati; Bahaadinbeigy, Kambiz; Khalilzadeh, Mohammad Mahdi


    In many countries, including our own, cardiovascular disease is the most common cause of mortality and morbidity. Myocardial infarction (heart attack) is of particular importance in heart disease as well as time and type of reaction to acute myocardial infarction and these can be a determining factor in patients' outcome. In order to reduce physician attendance time and keep patients informed about their condition, the smart phone as a common communication device has been used to process data and determine patients' ECG signals. For ECG signal analysis, we used time domain methods for extracting the ST-segment as the most important feature of the signal to detect myocardial infarction and the thresholding methods and linear classifiers by LabVIEW Mobile Module were used to determine signal risk. The sensitivity and specificity as criteria to evaluate the algorithm were 98% and 93.3% respectively in real time. This algorithm, because of the low computational load and high speed, makes it possible to run in a smart phone. Using Bluetooth to send the data from a portable monitoring system to a smart phone facilitates the real time applications. By using this program on the patient's mobile, timely detection of infarction so to inform patients is possible and mobile services such as SMS and calling for a physician's consultation can be done.

  11. Space Weather and Real-Time Monitoring


    Recent advance of information and communications technology enables to collect a large amount of ground-based and space-based observation data in real-time. The real-time data realize nowcast of space weather. This paper reports a history of space weather by the International Space Environment Service (ISES) in association with the International Geophysical Year (IGY) and importance of real-time monitoring in space weather.

  12. Space Weather and Real-Time Monitoring

    S Watari


    Full Text Available Recent advance of information and communications technology enables to collect a large amount of ground-based and space-based observation data in real-time. The real-time data realize nowcast of space weather. This paper reports a history of space weather by the International Space Environment Service (ISES in association with the International Geophysical Year (IGY and importance of real-time monitoring in space weather.

  13. Real-time graphics rendering engine

    Bao, Hujun


    ""Real-Time Graphics Rendering Engine"" reveals the software architecture of the modern real-time 3D graphics rendering engine and the relevant technologies based on the authors' experience developing this high-performance, real-time system. The relevant knowledge about real-time graphics rendering such as the rendering pipeline, the visual appearance and shading and lighting models are also introduced. This book is intended to offer well-founded guidance for researchers and developers who are interested in building their own rendering engines. Hujun Bao is a professor at the State Key Lab of

  14. Research in Distributed Real-Time Systems

    Mukkamala, R.


    This document summarizes the progress we have made on our study of issues concerning the schedulability of real-time systems. Our study has produced several results in the scalability issues of distributed real-time systems. In particular, we have used our techniques to resolve schedulability issues in distributed systems with end-to-end requirements. During the next year (1997-98), we propose to extend the current work to address the modeling and workload characterization issues in distributed real-time systems. In particular, we propose to investigate the effect of different workload models and component models on the design and the subsequent performance of distributed real-time systems.

  15. Real-time Pricing in Power Markets

    Boom, Anette; Schwenen, Sebastian

    We examine welfare eects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...

  16. Real-time Pricing in Power Markets

    Boom, Anette; Schwenen, Sebastian

    We examine welfare e ects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...

  17. Evaluation of left ventricular regional myocardial systolic function in patients with diastolic heart failure using real-time triplane strain rate imaging%实时三平面应变率成像评价舒张性心力衰竭患者左心室局部心肌收缩功能

    姜海燕; 王志斌; 聂晶; 李艳


    目的:应用实时三平面应变率成像检测舒张性心力衰竭患者左心室局部心肌收缩功能,探讨其临床意义.方法:选取舒张性心力衰竭患者29例、收缩性心力衰竭患者26例和正常人30例,应用实时三平面应变率成像测定左心室各壁基底段和中间段收缩期峰值应变率(SRs).结果:舒张性心力衰竭组、收缩性心力衰竭组左心室壁各节段SRs均小于正常组相应节段(P<0.05或P<0.01),且正常组、舒张性心力衰竭组、收缩性心力衰竭组各组SRs逐渐减小(P<0.05或P<0.01).结论:舒张性心力衰竭患者存在左心室局部心肌收缩功能异常,实时三平面应变率成像检测左心室局部心肌收缩功能在心力衰竭患者心脏功能评价中具有重要价值.%Objective: To evaluate the left ventricular regional myocardial systolic function in patients with diastolic heart failure using real-time triplane strain rate imaging and investigate its clinical significance.Methods: Twenty-nine patients with diastolic heart failure, 26 patients with systolic heart failure and 30 healthy subjects as control group were enrolled.The systolic peak strain rate (SRs) were measured at basal and middle segments in different left ventricular walls using real-time triplane strain rate imaging.Results: SRs in diastolic heart failure and systolic heart failure groups were significantly lower than in control group(P<0.05 or P<0.01).There was a significantly step-down change among normal, diastolic heart failure and systolic heart failure in SRs (P<0.05 or P<0.01).Conclusions: The left ventricular regional myocardial systolic dysfunction existed in patients with diastolic heart failure.Thus, assessing left ventricular regional myocardial systolic function using real-time triplane strain rate imaging has important clinical value in the comprehensive evaluation of cardiac function in heart failure.

  18. Identification of chronic myocardial infarction with extracellular or intravascular contrast agents in magnetic resonance imaging

    Jian WANG; Hong-yu LIU; Hang L(U); Bo XIANG; Marco GRUWEL; Boguslaw TOMANEK; Roxanne DESLAURIERS; Gang-hong TIAN


    Aim: To determine whether extracellular or intravascular contrast agents could detect chronic scarred myocardium in magnetic resonance imaging (MRI). Methods: Eighteen pigs underwent a 4 week ligation of 1 or 2 diagonal coronary arteries to induce chronic myocardial infarction. The hearts were then removed and perfused in a Langendorff apparatus. Eighteen hearts were divided into 2 groups. The hearts in groups Ⅰ (n=9) and Ⅱ (n=9) 收稿日期the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA, 0.05 mmol/kg) and ga-dolinium-based macromolecular agent (P792, 15 μmol/kg), respectively. First pass T2* MRI was acquired using a FLASH sequence. Delayed enhancement T1 MRI was acquired with an inversion recovery prepared TurboFLASH sequence.Results: Wash-in of both agents resulted in a sharp and dramatic T2* signal loss of scarred myocardium similar to that of normal myocardium. The magnitude and velocity of T2* signal recovery caused by wash-out of extracellular agents in normal myocardium was significantly less than that in scarred myocardium. Conversely, the T2* signal of scarred and normal myocardium recovered to plateau rapidly and simultaneously due to wash-out of intravascular agents. At the fol-lowing equilibrium, extracellular agent-enhanced T1 signal intensity was signifi-cantly greater in scarred myocardium than in normal myocardium, whereas there was no significantly statistical difference in intravascular agent-enhanced T1 sig-nal intensity between scarred and normal myocardium. Conclusion: After admin-istration of extracellular agents, wash-out T2* first-pass and delayed enhanced T1 MRI could identify scarred myocardium as a hyperenhanced region. Conversely, scarred myocardium was indistinguishable from normal myocardium during first-pass and the steady state of intravascular agents.

  19. Cardiovascular magnetic resonance by non contrast T1-mapping allows assessment of severity of injury in acute myocardial infarction


    Background Current cardiovascular magnetic resonance (CMR) methods, such as late gadolinium enhancement (LGE) and oedema imaging (T2W) used to depict myocardial ischemia, have limitations. Novel quantitative T1-mapping techniques have the potential to further characterize the components of ischemic injury. In patients with myocardial infarction (MI) we sought to investigate whether state-of the art pre-contrast T1-mapping (1) detects acute myocardial injury, (2) allows for quantification of the severity of damage when compared to standard techniques such as LGE and T2W, and (3) has the ability to predict long term functional recovery. Methods 3T CMR including T2W, T1-mapping and LGE was performed in 41 patients [of these, 78% were ST elevation MI (STEMI)] with acute MI at 12-48 hour after chest pain onset and at 6 months (6M). Patients with STEMI underwent primary PCI prior to CMR. Assessment of acute regional wall motion abnormalities, acute segmental damaged fraction by T2W and LGE and mean segmental T1 values was performed on matching short axis slices. LGE and improvement in regional wall motion at 6M were also obtained. Results We found that the variability of T1 measurements was significantly lower compared to T2W and that, while the diagnostic performance of acute T1-mapping for detecting myocardial injury was at least as good as that of T2W-CMR in STEMI patients, it was superior to T2W imaging in NSTEMI. There was a significant relationship between the segmental damaged fraction assessed by either by LGE or T2W, and mean segmental T1 values (P myocardial damage. T1-mapping might become an important complementary technique to LGE and T2W for identification of reversible myocardial injury and prediction of functional recovery in acute MI. PMID:22309452

  20. Storm real-time processing cookbook

    Anderson, Quinton


    A Cookbook with plenty of practical recipes for different uses of Storm.If you are a Java developer with basic knowledge of real-time processing and would like to learn Storm to process unbounded streams of data in real time, then this book is for you.

  1. Interactive Real-time Magnetic Resonance Imaging

    Brix, Lau

    Real-time acquisition, reconstruction and interactively changing the slice position using magnetic resonance imaging (MRI) have been possible for years. However, the current clinical use of interactive real-time MRI is limited due to an inherent low spatial and temporal resolution. This PhD proje...

  2. Validation of RNAi by real time PCR

    Josefsen, Knud; Lee, Ying Chiu


    Real time PCR is the analytic tool of choice for quantification of gene expression, while RNAi is concerned with downregulation of gene expression. Together, they constitute a powerful approach in any loss of function studies of selective genes. We illustrate here the use of real time PCR to veri...

  3. Real-time communication protocols: an overview

    Hanssen, Ferdy; Jansen, Pierre G.


    This paper describes several existing data link layer protocols that provide real-time capabilities on wired networks, focusing on token-ring and Carrier Sense Multiple Access based networks. Existing modifications to provide better real-time capabilities and performance are also described. Finally

  4. Real-time communication protocols: an overview

    Hanssen, Ferdy; Jansen, Pierre G.


    This paper describes several existing data link layer protocols that provide real-time capabilities on wired networks, focusing on token-ring and Carrier Sense Multiple Access based networks. Existing modifications to provide better real-time capabilities and performance are also described. Finally the pros and cons regarding the At-Home Anywhere project are discussed.

  5. Real-time Pricing in Power Markets

    Boom, Anette; Schwenen, Sebastian

    to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...

  6. Interactive Real-time Magnetic Resonance Imaging

    Brix, Lau

    Real-time acquisition, reconstruction and interactively changing the slice position using magnetic resonance imaging (MRI) have been possible for years. However, the current clinical use of interactive real-time MRI is limited due to an inherent low spatial and temporal resolution. This PhD proje...

  7. Steerable real-time sonographically guided needle biopsy.

    Buonocore, E; Skipper, G J


    A method for dynamic real-time ultrasonic guidance for percutaneous needle biopsy has been successful in obtaining cytologic and histologic specimens from abdominal masses. The system depends on a real-time ultrasonic transducer that has been rigidly attached to a laterally placed steerable needle holder. Using simple trigonometric functions, a chart has been derived that gives the exact angulation and needle length to produce quick, reliable, guided needle placements. Examples of successful renal, hepatobiliary, and retroperitoneal biopsies are presented. Advantages of this technique include speed, accuracy, low cost, three-dimensional format, and the omission of contrast media and radiation.

  8. High dynamic range real-time 3D shape measurement.

    Jiang, Chufan; Bell, Tyler; Zhang, Song


    This paper proposes a method that can measure high-contrast surfaces in real-time without changing camera exposures. We propose to use 180-degree phase-shifted (or inverted) fringe patterns to complement regular fringe patterns. If not all of the regular patterns are saturated, inverted fringe patterns are used in lieu of original saturated patterns for phase retrieval, and if all of the regular fringe patterns are saturated, both the original and inverted fringe patterns are all used for phase computation to reduce phase error. Experimental results demonstrate that three-dimensional (3D) shape measurement can be achieved in real time by adopting the proposed high dynamic range method.

  9. 探讨实时超声造影技术评价肝移植术前门静脉通畅性的研究%Study of Real-time Contrast-enhanced Ultrasound Technology Evaluation of Portal Vein Flow Resistance Preoperative Liver Transplantation



    目的:比较目前的两种超声技术,普通超声和实时超声造影技术对肝脏移植手术前门静脉的畅通性评价特点。方法:对经普通超声技术检查后被怀疑门静脉一级分支或主干中有栓塞的34例患者进行实时超声造影检查。结果:经螺旋CT的门静脉成像、三维动态磁共振的血管成像和肝移植手术等方法的证实,34例患者中有27例门静脉栓塞患者,7例门静脉畅通患者。普通超声技术和实时超声造影技术的诊断信心评分分别为(8.32±1.89)分和(9.29±1.01)分;普通超声技术和实时超声造影技术的敏感性分别为87.9%和81.9%,特异性分别为32.8%和100%,准确性分别为68.7%和89.1%;鉴别栓子程度和栓子性质时,实时超声造影技术明显优于普通超声技术。其中,对于在实时超声造影技术中显示的16例门静脉栓塞患者,实时超声造影技术是可以百分百全部鉴别的,但在普通超声技术可以显示的17例门静脉栓塞患者中,只能鉴别出9例患者。结论:在肝移植手术前诊断门静脉的畅通性时,实时超声造影技术的诊断水平明显高于普通超声技术,能够提供更准确、丰富的术前诊断信息,实时超声造影技术可以很好地补充普通超声技术,值得临床推广应用。%Objective:To compare the two kinds of ultrasonic imaging technology,common ultrasonic and real-time contrast-enhanced ultrasound technology to the smooth general characteristic evaluation characteristic of portal vein flow preoperative liver transplantation.Method:For suspected portal vein after normal ultrasound examination level branches or trunk of 34 patients with embolization were given real-time contrast-enhanced ultrasound examination.Result:The spiral CT portal imaging,3D dynamic magnetic resonance angiography and the proof of the method such as a liver transplant confirmed,in 34 patients,there were 27 cases of portal vein

  10. Validation of Contrast Enhanced Cine Steady-State Free Precession and T2-Weigthed CMR for Assessment of Ischemic Myocardial Area- At-Risk

    Søvsø Szocska Hansen, Esben; Pedersen, Steen Fjord; Pedersen, Steen Bønløkke


    Measuring myocardial salvage is important to evaluate the possible cardioprotective effects of adjunctive cardioprotective intervention in patients with myocardial infarction undergoing primary percutaneous intervention. Contrast-enhanced steady-state free precession magnetic resonance imaging (CE-CINE......) has recently been used to quantify AAR and validated against myocardial perfusion SPECT. In this study we sought to determine how well T2-STIR and CE-CINE depicts AAR in an experimental porcine model of myocardial ischemia-reperfusion injury using histopathology as the reference for infarct size...

  11. Myocardial contrast echocardiography (MCE) with triggered ultrasound does not cause premature ventricular complexes: evidence from PB127 MCE studies.

    Raisinghani, Ajit; Wei, Kevin S; Crouse, Linda; Villanueva, Floredeliza; Feigenbaum, Harvey; Schiller, Nelson B; Weiss, James; Naqvi, Tasneem Z; Siegel, Robert; Monaghan, Mark; Goldman, Jonathan H; Demaria, Anthony


    Previous studies suggest that myocardial contrast echocardiography using high mechanical index triggered ultrasound can be associated with increased frequency of the premature ventricular complex (PVC). However, this association has not been systematically examined. PB127 (Point Biomedical Corp, San Carlos, Calif) is a novel microsphere designed for evaluation of myocardial perfusion with ultrasound. PB127 myocardial contrast echocardiography was performed with triggered harmonic power Doppler in early/mid diastole (mechanical index premature ventricular complex frequency at baseline, during, and after infusion of PB127 (dose premature ventricular complex were determined. PVC frequency did not increase with PB127 infusion in either cohort (P =.572, P =.263). Proportion of triggered intervals after QRS associated with PVC was similar to proportion of untriggered intervals in cohort A (P >.999) and was lower than untriggered intervals (P =.001) in B, suggesting that triggers do not cause PVC. PB127 does not cause increase PVC frequency during or after imaging with triggered ultrasound at mechanical index of 1.

  12. Comparison of Myocardial Perfusion Estimates From Dynamic Contrast-Enhanced Magnetic Resonance Imaging With Four Quantitative Analysis Methods

    Pack, Nathan A.; DiBella, Edward V. R.


    Dynamic contrast-enhanced MRI has been used to quantify myocardial perfusion in recent years. Published results have varied widely, possibly depending on the method used to analyze the dynamic perfusion data. Here, four quantitative analysis methods (two-compartment modeling, Fermi function modeling, model-independent analysis, and Patlak plot analysis) were implemented and compared for quantifying myocardial perfusion. Dynamic contrast-enhanced MRI data were acquired in 20 human subjects at rest with low-dose (0.019 ± 0.005 mmol/kg) bolus injections of gadolinium. Fourteen of these subjects were also imaged at adenosine stress (0.021 ± 0.005 mmol/kg). Aggregate rest perfusion estimates were not significantly different between all four analysis methods. At stress, perfusion estimates were not significantly different between two-compartment modeling, model-independent analysis, and Patlak plot analysis. Stress estimates from the Fermi model were significantly higher (~20%) than the other three methods. Myocardial perfusion reserve values were not significantly different between all four methods. Model-independent analysis resulted in the lowest model curve-fit errors. When more than just the first pass of data was analyzed, perfusion estimates from two-compartment modeling and model-independent analysis did not change significantly, unlike results from Fermi function modeling. PMID:20577976

  13. The ALMA Real Time Control System

    Kern, Jeffrey S.; Juerges, Thomas A.; Marson, Ralph G.


    The Atacama Large Millimeter Array (ALMA) is a revolutionary millimeter and submillimeter array being developed on the Atacama plateau of northern Chile. An international partnership lead by NRAO, ESO, and NAOJ this powerful and flexible telescope will provide unprecedented observations of this relatively unexplored frequency range. The control subsystem for the Atacama Large Millimeter Array must coordinate the monitor and control of at least sixty six antennas (in four different styles), two correlators, and all of the ancillary equipment (samplers, local oscillators, front ends, etc.). This equipment will be spread over tens of kilometers and operated remotely. Operation of the array requires a robust, scalable, and maintainable real time control system. The real time control system is responsible for monitoring and control of any devices where there are fixed deadlines. Examples in the ALMA context are antenna pointing and fringe tracking. Traditionally the real time portion of a large software system is an intricate and error prone portion of the software. As a result the real time portion is very expensive in terms of effort expended both during construction and during maintenance phases of a project. The ALMA real time control system uses a Linux based real time operating system to interact with the hardware and the CORBA based ALMA Common Software to communicate in the distributed computing environment. Mixing the requirements of real time computing and the non-deterministic CORBA middleware has produced an interesting design. We discuss the architecture, design, and implementation of the ALMA real time control system. Highlight some lessons learned along the way, and justify our assertion that this should be the last large scale real time control system in radio astronomy.

  14. Achieving real-time performance in FIESTA

    Wilkinson, William; Happell, Nadine; Miksell, Steve; Quillin, Robert; Carlisle, Candace


    The Fault Isolation Expert System for TDRSS Applications (FIESTA) is targeted for operation in a real-time online environment. Initial stages of the prototype development concentrated on acquisition and representation of the knowledge necessary to isolate faults in the TDRSS Network. Recent efforts focused on achieving real-time performance including: a discussion of the meaning of FIESTA real-time requirements, determination of performance levels (benchmarking) and techniques for optimization. Optimization techniques presented include redesign of critical relations, filtering of redundant data and optimization of patterns used in rules. Results are summarized.

  15. Real-time medical applications and telecommunications.

    Stravs, M


    Telecommunications play an important role in telemedicine. Many forms of telecommunication services based on different telecommunication technologies are developed for various needs. The paper deals with complex real-time applications which demand high telecommunication requirements. At the beginning, medical applications are categorised and real-time applications qualified as multimedia applications. Requirements for multimedia elements are listed separately. Later on, short introduction of related telecommunication protocols is given. Real-time medical applications can show their ability in case of guaranteed quality of services delivered by telecommunication network as it is explained in the end.

  16. Real time detecting system for turning force

    Yue Xiao Bin


    How to get the real-time value of forces dropped on the tool in the course of processing by piezoelectric sensors is introduced. First, the analog signals of the cutting force were achieved by these sensors, amplified and transferred into digital signals by A/D transferring card. Then real-time software reads the information, put it into its own coordinate, drew the curve of forces, displayed it on the screen by the real time and saved it for the technicians to analyze the situation of the tool. So the cutting parameter can be optimized to improve surface quality of the pieces

  17. Visualization in Real-Time Experiment Project

    National Aeronautics and Space Administration — The objective of this project will be to migrate some of the outputs from the WFF Mission Planning Lab (MPL) into a real-time visualization system.  The MPL is...

  18. Real Time Study and Related Variables

    WU Xiao-qing


    This paper first, illustrates the advantages of applying real time study to linguistic researches. Second, this paper also compares linguistic variables with linguistic variant; nasality, stronger constraint and weaker constraint have been clearly de-fined as well.

  19. Multiprocessor scheduling for real-time systems

    Baruah, Sanjoy; Buttazzo, Giorgio


    This book provides a comprehensive overview of both theoretical and pragmatic aspects of resource-allocation and scheduling in multiprocessor and multicore hard-real-time systems.  The authors derive new, abstract models of real-time tasks that capture accurately the salient features of real application systems that are to be implemented on multiprocessor platforms, and identify rules for mapping application systems onto the most appropriate models.  New run-time multiprocessor scheduling algorithms are presented, which are demonstrably better than those currently used, both in terms of run-time efficiency and tractability of off-line analysis.  Readers will benefit from a new design and analysis framework for multiprocessor real-time systems, which will translate into a significantly enhanced ability to provide formally verified, safety-critical real-time systems at a significantly lower cost.

  20. Real-Time Sensor-Actuator Networks

    Sastry, Shivakumar; S. S. Iyengar


    Emerging technologies offer new paradigms for computation, control, collaboration, and communication. To realize the full potential of these technologies in industry, defense, and homeland security applications, it is necessary to exploit the real-time distributed computing capabilities of sensor-actuator networks. To reliably design and develop such networks, it is necessary to develop deeper insight into the underlying model for real-time computation and the infrastructure at the node level...

  1. Real Time Information Fusion in Military Systems

    E. Bhagiratharao


    Full Text Available With the proliferation of sensors on platforms like battle ships and aircraft, the information to be handled by the battlefield commanders has significantly increased in the recent time. From a deluge of information flowing from sensors, the battlefield commander is required to make situation assessment in real-time and take appropriate action. Recent studies by cognitive scientists have indicated that decision making by individuals as well as a team suffer from several biases. For these two reasons, the battlefield commanders need assistance of real-time information fusion systems to take objective assessment of highly dynamic battle situation in real-time information fusion systems to take objective assessment of a highly dynamic battle situation in real-time. The real-time information fusion systems at a single platform level as well as that applicable for geographically distributed platforms is discussed in detail in this paper. It was concluded that by carrying out these activities at the platform level as well as at 'global' level involving several platforms, the limitations in performance of any sensor due to propagation effects or due to enemy counter measures can be significantly minimised or totally eliminated. At the same time the functional effectiveness of each sensor onboard different platforms, becomes better than when it had to operate autonomously within the real-time information fusion facility. By carrying out global real-time information fusion activity in a theatre of war, all the platforms operating in the area will have the benefit of the best sensor in that area on each aspect of the capability. A few examples of real-time information fusion system are also discussed.

  2. Scala for Real-Time Systems?

    Schoeberl, Martin


    Java served well as a general-purpose language. However, during its two decades of constant change it has gotten some weight and legacy in the language syntax and the libraries. Furthermore, Java's success for real-time systems is mediocre. Scala is a modern object-oriented and functional language...... with interesting new features. Although a new language, it executes on a Java virtual machine, reusing that technology. This paper explores Scala as language for future real-time systems....

  3. The LAA real-time benchmarks

    Block, R.K.; Krischer, W.; Lone, S. [CERN, Geneva (Switzerland)


    In the context of the LAA detector development program a subgroup Real Time Data Processing has tackled the problem of intelligent triggering. The main goal of this group is to show how fast digital devices, implemented as custom-made or commercial processors, can execute some basic algorithms, and how they can be embedded in the data flow between detector readout components and fully programmable commercial processors, which are expected to be the final data processing filter in real time.

  4. Determinants of microvascular damage recovery after acute myocardial infarction: results from the acute myocardial infarction contrast imaging (AMICI) multi-centre study.

    Funaro, Stefania; Galiuto, Leonarda; Boccalini, Francesca; Cimino, Sara; Canali, Emanuele; Evangelio, Francesca; DeLuca, Laura; Paraggio, Lazzaro; Mattatelli, Antonella; Gnessi, Lucio; Agati, Luciano


    Microvascular damage (MD) occurring soon after primary percutaneous coronary intervention (PPCI) may reverse or remain sustained within the first week after ST-elevation myocardial infarction (STEMI). We investigated the incidence, determinants, and long-term clinical relevance of MD reversal after PPCI. Serial two-dimensional echocardiograms (2DE) and a myocardial contrast study were obtained within 24 h of PPCI (T1) and at pre-discharge (T2) in 110 successfully re-perfused STEMI patients. Six months 2DE and 2-year clinical follow-up were obtained. After PPCI myocardial re-perfusion was normal at T1 only in 40 patients (36%, 'normal reflow'), recovered at T2 in 33 (30%, 'reversible MD'), and remained abnormal in 37 (34%, 'sustained MD'). At follow-up, normal reflow and reversible MD were coupled with a significant reduction in the infarct area, decrease in cardiac volumes, and a slight non-significant improvement in systolic function. Conversely, in the sustained MD group, the infarct area did not change and cardiac volumes significantly increased with a parallel worsening in systolic function. By multivariate analysis, independent predictors of reversible MD were: absence of family history of coronary artery disease (CAD), younger age, shorter time to re-perfusion, and absence of diabetes. The 2-year combined events rate was significantly lower in reversible MD (log-rank test P= 0.03) compared with sustained MD patients. In STEMI patients treated according to the current guidelines, MD frequently occurs soon after re-perfusion but it is reversible in ~50% of cases and it is associated with a favourable functional and clinical outcome. Family history of CAD, aging, time to re-perfusion, and diabetes are independent predictors of MD reversibility.

  5. Analysis of real-time vibration data

    Safak, E.


    In recent years, a few structures have been instrumented to provide continuous vibration data in real time, recording not only large-amplitude motions generated by extreme loads, but also small-amplitude motions generated by ambient loads. The main objective in continuous recording is to track any changes in structural characteristics, and to detect damage after an extreme event, such as an earthquake or explosion. The Fourier-based spectral analysis methods have been the primary tool to analyze vibration data from structures. In general, such methods do not work well for real-time data, because real-time data are mainly composed of ambient vibrations with very low amplitudes and signal-to-noise ratios. The long duration, linearity, and the stationarity of ambient data, however, allow us to utilize statistical signal processing tools, which can compensate for the adverse effects of low amplitudes and high noise. The analysis of real-time data requires tools and techniques that can be applied in real-time; i.e., data are processed and analyzed while being acquired. This paper presents some of the basic tools and techniques for processing and analyzing real-time vibration data. The topics discussed include utilization of running time windows, tracking mean and mean-square values, filtering, system identification, and damage detection.

  6. Variational optical flow computation in real time.

    Bruhn, Andrés; Weickert, Joachim; Feddern, Christian; Kohlberger, Timo; Schnörr, Christoph


    This paper investigates the usefulness of bidirectional multigrid methods for variational optical flow computations. Although these numerical schemes are among the fastest methods for solving equation systems, they are rarely applied in the field of computer vision. We demonstrate how to employ those numerical methods for the treatment of variational optical flow formulations and show that the efficiency of this approach even allows for real-time performance on standard PCs. As a representative for variational optic flow methods, we consider the recently introduced combined local-global method. It can be considered as a noise-robust generalization of the Horn and Schunck technique. We present a decoupled, as well as a coupled, version of the classical Gauss-Seidel solver, and we develop several multgrid implementations based on a discretization coarse grid approximation. In contrast, with standard bidirectional multigrid algorithms, we take advantage of intergrid transfer operators that allow for nondyadic grid hierarchies. As a consequence, no restrictions concerning the image size or the number of traversed levels have to be imposed. In the experimental section, we juxtapose the developed multigrid schemes and demonstrate their superior performance when compared to unidirectional multgrid methods and nonhierachical solvers. For the well-known 316 x 252 Yosemite sequence, we succeeded in computing the complete set of dense flow fields in three quarters of a second on a 3.06-GHz Pentium4 PC. This corresponds to a frame rate of 18 flow fields per second which outperforms the widely-used Gauss-Seidel method by almost three orders of magnitude.

  7. Theoretical considerations in measurement of time discrepancies between input and myocardial time-signal intensity curves in estimates of regional myocardial perfusion with first-pass contrast-enhanced MRI.

    Natsume, Takahiro; Ishida, Masaki; Kitagawa, Kakuya; Nagata, Motonori; Sakuma, Hajime; Ichihara, Takashi


    The purpose of this study was to develop a method to determine time discrepancies between input and myocardial time-signal intensity (TSI) curves for accurate estimation of myocardial perfusion with first-pass contrast-enhanced MRI. Estimation of myocardial perfusion with contrast-enhanced MRI using kinetic models requires faithful recording of contrast content in the blood and myocardium. Typically, the arterial input function (AIF) is obtained by setting a region of interest in the left ventricular cavity. However, there is a small delay between the AIF and the myocardial curves, and such time discrepancies can lead to errors in flow estimation using Patlak plot analysis. In this study, the time discrepancies between the arterial TSI curve and the myocardial tissue TSI curve were estimated based on the compartment model. In the early phase after the arrival of the contrast agent in the myocardium, the relationship between rate constant K1 and the concentrations of Gd-DTPA contrast agent in the myocardium and arterial blood (LV blood) can be described by the equation K1={dCmyo(tpeak)/dt}/Ca(tpeak), where Cmyo(t) and Ca(t) are the relative concentrations of Gd-DTPA contrast agent in the myocardium and in the LV blood, respectively, and tpeak is the time corresponding to the peak of Ca(t). In the ideal case, the time corresponding to the maximum upslope of Cmyo(t), tmax, is equal to tpeak. In practice, however, there is a small difference in the arrival times of the contrast agent into the LV and into the myocardium. This difference was estimated to correspond to the difference between tpeak and tmax. The magnitudes of such time discrepancies and the effectiveness of the correction for these time discrepancies were measured in 18 subjects who underwent myocardial perfusion MRI under rest and stress conditions. The effects of the time discrepancies could be corrected effectively in the myocardial perfusion estimates.


    Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo


    The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stability monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.

  9. Detection of myocardial fibrosis in systemic sclerosis by contrast-enhanced magnetic resonance imaging

    Nassenstein, K.; Ladd, S.C.; Schlosser, T. [Abt. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Universitaetsklinikum Essen (Germany); Breuckmann, F. [Westdeutsches Herzzentrum, Klinik fuer Kardiologie, Universitaetsklinikum Essen (Germany); Huger, M.; Kreuter, A. [Klinik fuer Dermatologie und Allergologie, St.-Josef-Hospital Bochum, Klinikum der Ruhr-Univ. Bochum (Germany); Barkhausen, J. [Klinik fuer Radiologie und Nuklearmedizin, Universitaetsklinikum Schleswig-Holstein, Campus Luebeck (Germany)


    Purpose: our study aimed to assess the prevalence and pattern of late gadolinium enhancement (LGE) as an in vivo correlate of myocardial fibrosis in cardiac asymptomatic patients with systemic sclerosis (SSc). Materials and methods: cardiac magnetic resonance imaging was successfully performed in 34 patients (30 female, 4 male, mean age of 54 {+-} 14 years) with proven SSc and in controls with matching age, sex and cardiovascular risk factors. All examinations were performed on a 1.5 T MR system (Avanto, Siemens, Germany). 2D inversion recovery spoiled gradient echo images (TR 8.0 msec, TE4.0 msec, TI180-240 msec, FA20 , slice thickness 8 mm, in-plane resolution 1.2 x 1.2 mm{sup 2}) were acquired 10 to 15 min after injection of 0.2 mmol Gd-DTPA per kg body weight to detect myocardial LGE. Results: poorly defined, patchy as well as well-defined focal areas of LGE were detected predominantly in the mid-myocardial layer of the basal left ventricular segments in 5 of 34 (15%) SSc patients. A focal area of LGE was observed within the apical septum in one control (3%, p > 0.05). LGE was observed in a total of 15 segments of the SSc patients and in 1 segment of the controls (p < 0.005). (orig.)

  10. Visualization of Real-Time Data

    Stansifer, Ryan; Engrand, Peter


    In this project we explored various approaches to presenting real-time data from the numerous systems monitored on the space shuttle to computer users. We examined the approach that several projects at the Kennedy Space Center (KSC) used to accomplish this. We undertook to build a prototype system to demonstrate that the Internet and the Java programming language could be used to present the real-time data conveniently. Several Java programs were developed that presented real-time data in different forms including one form that emulated the display screens of the PC GOAL system which is familiar to many at KSC. Also, we developed several communications programs to supply the data continuously. Furthermore, a framework was created using the World Wide Web (WWW) to organize the collection and presentation of the real-time data. We believe our demonstration project shows the great flexibility of the approach. We had no particular use of the data in mind, instead we wanted the most general and the least complex framework possible. People who wish to view data need only know how to use a WWW browser and the address (the URL). People wanting to build WWW documents containing real-time data need only know the values of a few parameters, they do not need to program in Java or any other language. These are stunning advantages over more monolithic systems.

  11. Tests of equal predictive ability with real-time data

    Todd E. Clark; Michael W. McCracken


    This paper examines the asymptotic and finite-sample properties of tests of equal forecast accuracy applied to direct, multi-step predictions from both non-nested and nested linear regression models. In contrast to earlier work -- including West (1996), Clark and McCracken (2001, 2005),and McCracken (2006) -- our asymptotics take account of the real-time, revised nature of the data. Monte Carlo simulations indicate that our asymptotic approximations yield reasonable size and power properties ...

  12. 实时组织弹性超声成像定量评价猪离体心室心肌弹性%Quantitative assessment of myocardial elasticity in isolated porcine ventricular wall with real-time ultrasonic tissue elastography

    张丽娟; 尹立雪; 王志刚; 甘建红; 陆景


    Objective To assess myocardial elasticity in the isolated porcine ventricular wall using real-time ultrasonic tis sue elastography (RTE) technology,and to explore the correlation between myocardial elasticity and the tissue element and three-dimension distribution of myocardial interstitial collagen fibers.Methods Ten isolated porcine hearts were collected.Cubical segments were excised from left and right ventricular (LV,RV) anterior walls and interventricular septum (IVS) at the base,respectively.Along the ventricular long and short-axis direction,the elastic strain ratio (SR) of 2% agar with out collagen fibers to the myocardium were measured and calculated using RTE.Combined with the area (CA) and the area percentage (CA%) of collagen fibers in the three locations of patho-histological slice with Masson's Trichrome stain,SR,CA and CA% were compared among the three locations.Correlations between SR of myocardial elasticity and CA,CA% in the three locations were analyzed.Results Along the ventricular long-axis direction,there were statistically significant differences of SR among LV,RV and IVS,respectively (P<0.01) and between the ventricular long-axis direction and short-axis direction at IVS (P<0.01).Along the ventricular long-axis direction,there were statistically significant differences of CA and CA% among LV,RV and IVS (all P<0.05) and between the ventricular long-axis direction and short-axis direction at IVS (P<0.05).Statistically significant positive linear correlations between SR and CA,CA% were found (all P<0.05).Conclusion SR of porcine myocardial tissue among LV,RV and IVS are different.Myocardial elasticity of porcine has correlation with tissue element and distribution of myocardial interstitial collagen fibers.%目的 应用实时组织弹性超声成像(RTE)技术定量评价猪离体心室心肌弹性,探讨心肌弹性与心肌间质胶原纤维含量及其三维分布的关系.方法 离体猪心10个,分别切取左、

  13. Interactive Real-time Magnetic Resonance Imaging

    Brix, Lau

    seeks to implement and assess existing reconstruction algorithms using multi-processors of modern graphics cards and many-core computer processors and to cover some of the potential clinical applications which might benefit from using an interactive real-time MRI system. First an off......-line, but interactive, slice alignment tool was used to support the notion that 3D blood flow quantification in the heart possesses the ability to obtain curves and volumes which are not statistical different from standard 2D flow. Secondly, the feasibility of an interactive real-time MRI system was exploited...... with regard to optimal sampling strategy for detecting motion in four different anatomies on two different MRI scanner brands. A fully implemented interactive real-time MRI system was exploited in a group of healthy fetuses and proved its eligibility as an alternative diagnostic tool for fetal imaging...

  14. Deterministic Real-time Thread Scheduling

    Yun, Heechul; Sha, Lui


    Race condition is a timing sensitive problem. A significant source of timing variation comes from nondeterministic hardware interactions such as cache misses. While data race detectors and model checkers can check races, the enormous state space of complex software makes it difficult to identify all of the races and those residual implementation errors still remain a big challenge. In this paper, we propose deterministic real-time scheduling methods to address scheduling nondeterminism in uniprocessor systems. The main idea is to use timing insensitive deterministic events, e.g, an instruction counter, in conjunction with a real-time clock to schedule threads. By introducing the concept of Worst Case Executable Instructions (WCEI), we guarantee both determinism and real-time performance.

  15. Continuous, real time microwave plasma element sensor

    Woskov, Paul P.; Smatlak, Donna L.; Cohn, Daniel R.; Wittle, J. Kenneth; Titus, Charles H.; Surma, Jeffrey E.


    Microwave-induced plasma for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury.

  16. Durham adaptive optics real-time controller.

    Basden, Alastair; Geng, Deli; Myers, Richard; Younger, Eddy


    The Durham adaptive optics (AO) real-time controller was initially a proof of concept design for a generic AO control system. It has since been developed into a modern and powerful central-processing-unit-based real-time control system, capable of using hardware acceleration (including field programmable gate arrays and graphical processing units), based primarily around commercial off-the-shelf hardware. It is powerful enough to be used as the real-time controller for all currently planned 8 m class telescope AO systems. Here we give details of this controller and the concepts behind it, and report on performance, including latency and jitter, which is less than 10 μs for small AO systems.

  17. Real-Time Visualization of Tissue Ischemia

    Bearman, Gregory H. (Inventor); Chrien, Thomas D. (Inventor); Eastwood, Michael L. (Inventor)


    A real-time display of tissue ischemia which comprises three CCD video cameras, each with a narrow bandwidth filter at the correct wavelength is discussed. The cameras simultaneously view an area of tissue suspected of having ischemic areas through beamsplitters. The output from each camera is adjusted to give the correct signal intensity for combining with, the others into an image for display. If necessary a digital signal processor (DSP) can implement algorithms for image enhancement prior to display. Current DSP engines are fast enough to give real-time display. Measurement at three, wavelengths, combined into a real-time Red-Green-Blue (RGB) video display with a digital signal processing (DSP) board to implement image algorithms, provides direct visualization of ischemic areas.

  18. Axial Tomography from Digitized Real Time Radiography

    Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.


    Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

  19. SignalR real time application development

    Ingebrigtsen, Einar


    This step-by-step guide gives you practical advice, tips, and tricks that will have you writing real-time apps quickly and easily.If you are a .NET developer who wants to be at the cutting edge of development, then this book is for you. Real-time application development is made simple in this guide, so as long as you have basic knowledge of .NET, a copy of Visual Studio, and NuGet installed, you are ready to go.

  20. Real-time Shakemap implementation in Austria

    Weginger, Stefan; Jia, Yan; Papi Isaba, Maria; Horn, Nikolaus


    ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes. They are automatically generated within a few minutes after occurrence of an earthquake. We tested and included the USGS ShakeMap 4.0 (experimental code) based on python in the Antelope real-time system with local modified GMPE and Site Effects based on the conditions in Austria. The ShakeMaps are provided in terms of Intensity, PGA, PGV and PSA. Future presentation of ShakeMap contour lines and Ground Motion Parameter with interactive maps and data exchange over Web-Services are shown.

  1. Real Time Implementation Of Face Recognition System

    Megha Manchanda


    Full Text Available This paper proposes face recognition method using PCA for real time implementation. Nowadays security is gaining importance as it is becoming necessary for people to keep passwords in their mind and carry cards. Such implementations however, are becoming less secure and practical, also is becoming more problematic thus leading to an increasing interest in techniques related to biometrics systems. Face recognition system is amongst important subjects in biometrics systems. This system is very useful for security in particular and has been widely used and developed in many countries. This study aims to achieve face recognition successfully by detecting human face in real time, based on Principal Component Analysis (PCA algorithm.

  2. Real-time systems scheduling fundamentals

    Chetto, Maryline


    Real-time systems are used in a wide range of applications, including control, sensing, multimedia, etc.  Scheduling is a central problem for these computing/communication systems since responsible of software execution in a timely manner. This book provides state of knowledge in this domain with special emphasis on the key results obtained within the last decade. This book addresses foundations as well as the latest advances and findings in Real-Time Scheduling, giving all references to important papers. But nevertheless the chapters will be short and not overloaded with confusing details.

  3. Real-time systems scheduling 2 focuses

    Chetto, Maryline


    Real-time systems are used in a wide range of applications, including control, sensing, multimedia, etc. Scheduling is a central problem for these computing/communication systems since it is responsible for software execution in a timely manner. This book, the second of two volumes on the subject, brings together knowledge on specific topics and discusses the recent advances for some of them.  It addresses foundations as well as the latest advances and findings in real-time scheduling, giving comprehensive references to important papers, but the chapters are short and not overloaded with co

  4. Real-time elastography of the prostate.

    Junker, D; De Zordo, T; Quentin, M; Ladurner, M; Bektic, J; Horniger, W; Jaschke, W; Aigner, F


    Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, real-time elastography has been used for several years for prostate cancer detection. This review introduces the different techniques of ultrasound elastography and furthermore summarises its limitations and potentials.

  5. Real-Time Elastography of the Prostate

    D. Junker


    Full Text Available Palpation of organs is one of the oldest clinical examination techniques, for instance, if you think of the palpation of the breast or the digital rectal examination of the prostate, where hard palpable regions are suspicious for cancer. This is the basic principle of real-time elastography, an ultrasound technique, which is able to visualise tissue elasticity. Since prostate cancer features an increased stiffness due to the higher cell and vessel density than the normal surrounding tissue, real-time elastography has been used for several years for prostate cancer detection. This review introduces the different techniques of ultrasound elastography and furthermore summarises its limitations and potentials.

  6. Integration of myocardial scar identified by preoperative delayed contrast-enhanced MRI into a high-resolution mapping system for planning and guidance of VT ablation procedures

    Rettmann, M. E.; Suzuki, A.; Wang, S.; Pottinger, N.; Arter, J.; Netzer, A.; Parker, K.; Viker, K.; Packer, D. L.


    Myocardial scarring creates a substrate for reentrant circuits which can lead to ventricular tachycardia. In ventricular catheter ablation therapy, regions of myocardial scarring are targeted to interrupt arrhythmic electrical pathways. Low voltage regions are a surrogate for myocardial scar and are identified by generating an electro anatomic map at the start of the procedure. Recent efforts have focussed on integration of preoperative scar information generated from delayed contrast-enhanced MR imaging to augment intraprocedural information. In this work, we describe an initial feasibility study of integration of a preoperative MRI derived scar maps into a high-resolution mapping system to improve planning and guidance of VT ablation procedures.

  7. Feedback as Real-Time Constructions

    Keiding, Tina Bering; Qvortrup, Ane


    This article offers a re-description of feedback and the significance of time in feedback constructions based on systems theory. It describes feedback as internal, real-time constructions in a learning system. From this perspective, feedback is neither immediate nor delayed, but occurs in the very moment it takes place. This article argues for a…

  8. Advances in Real-Time Systems

    Chakraborty, Samarjit


    This volume contains the lectures given in honor to Georg Farber as tribute to his contributions in the area of real-time and embedded systems. The chapters of many leading scientists cover a wide range of aspects, like robot or automotive vision systems or medical aspects.

  9. Quantitative real-time imaging of glutathione

    Glutathione plays many important roles in biological processes; however, the dynamic changes of glutathione concentrations in living cells remain largely unknown. Here, we report a reversible reaction-based fluorescent probe—designated as RealThiol (RT)—that can quantitatively monitor the real-time ...

  10. The Power of Real-Time PCR

    Valasek, Mark A.; Repa, Joyce J.


    In recent years, real-time polymerase chain reaction (PCR) has emerged as a robust and widely used methodology for biological investigation because it can detect and quantify very small amounts of specific nucleic acid sequences. As a research tool, a major application of this technology is the rapid and accurate assessment of changes in gene…

  11. Real-time dynamics of proton decay

    Grigoriev, D


    Substituting Skyrmion for nucleon, one can potentially see -- in real time -- how the monopole is catalysing the proton (or neutron) decay, and even obtain a plausible estimate for catalysis cross-section. Here we discuss the key aspects of a practical implementation of such approach and demonstrate how one can overcome the main technical problems: Gauss constraint violation and reflections at the boundaries.

  12. Refactoring Real-Time Java Profiles

    Søndergaard, Hans; Thomsen, Bent; Ravn, Anders Peter


    Just like other software, Java profiles benefits from refactoring when they have been used and have evolved for some time. This paper presents a refactoring of the Real-Time Specification for Java (RTSJ) and the Safety Critical Java (SCJ) profile (JSR-302). It highlights core concepts and makes...

  13. Studying Complex Interactions in Real Time


    The study of human behavior must take into account the social context, and real-time, networked experiments with multiple participants is one increasingly popular way to achieve this. In this paper a framework based on Python and XMPP is presented that aims to make it easy to develop such behavio...

  14. Feedback as Real-Time Constructions

    Keiding, Tina Bering; Qvortrup, Ane


    This article offers a re-description of feedback and the significance of time in feedback constructions based on systems theory. It describes feedback as internal, real-time constructions in a learning system. From this perspective, feedback is neither immediate nor delayed, but occurs in the very moment it takes place. This article argues for a…

  15. Real Time Grid Reliability Management 2005

    Eto, Joe; Eto, Joe; Lesieutre, Bernard; Lewis, Nancy Jo; Parashar, Manu


    The increased need to manage California?s electricity grid in real time is a result of the ongoing transition from a system operated by vertically-integrated utilities serving native loads to one operated by an independent system operator supporting competitive energy markets. During this transition period, the traditional approach to reliability management -- construction of new transmission lines -- has not been pursued due to unresolved issues related to the financing and recovery of transmission project costs. In the absence of investments in new transmission infrastructure, the best strategy for managing reliability is to equip system operators with better real-time information about actual operating margins so that they can better understand and manage the risk of operating closer to the edge. A companion strategy is to address known deficiencies in offline modeling tools that are needed to ground the use of improved real-time tools. This project: (1) developed and conducted first-ever demonstrations of two prototype real-time software tools for voltage security assessment and phasor monitoring; and (2) prepared a scoping study on improving load and generator response models. Additional funding through two separate subsequent work authorizations has already been provided to build upon the work initiated in this project.

  16. Scene independent real-time indirect illumination

    Frisvad, Jeppe Revall; Christensen, Niels Jørgen; Falster, Peter


    -time rendering of arbitrary dynamic environments and for interactive preview of feature animations. Through DRM we simulate two diffuse reflections of light, but can also, in combination with traditional real-time methods for specular reflections, simulate more complex light paths. DRM is a GPU-based method...

  17. Real time estimates of GDP growth

    Groot, de E.A. (Bert); Franses, P.H.P.H.


    This paper describes the components of the EICIE, the Econometric Institute Current Indicator of the Economy. This measure concerns quarterly and annual growth of Dutch real Gross Domestic Product. The key component of our real-time forecasting model for Dutch quarterly GDP is weekly staffing servic

  18. Real-time Texture Error Detection

    Dan Laurentiu Lacrama


    Full Text Available This paper advocates an improved solution for the real-time error detection of texture errors that occurs in the production process in textile industry. The research is focused on the mono-color products with 3D texture model (Jacquard fabrics. This is a more difficult task than, for example, 2D multicolor textures.

  19. Refactoring Real-Time Java Profiles

    Søndergaard, Hans; Thomsen, Bent; Ravn, Anders Peter


    Just like other software, Java profiles benefits from refactoring when they have been used and have evolved for some time. This paper presents a refactoring of the Real-Time Specification for Java (RTSJ) and the Safety Critical Java (SCJ) profile (JSR-302). It highlights core concepts and makes...

  20. Real time estimates of GDP growth

    E.A. de Groot (Bert); Ph.H.B.F. Franses (Philip Hans)


    textabstractThis paper describes the components of the EICIE, the Econometric Institute Current Indicator of the Economy. This measure concerns quarterly and annual growth of Dutch real Gross Domestic Product. The key component of our real-time forecasting model for Dutch quarterly GDP is weekly sta

  1. Real-time analysis of telemetry data

    Kao, Simon A.; Laffey, Thomas J.; Schmidt, James L.; Read, Jackson Y.; Dunham, Larry L.


    This paper descibes a knowledge-based system for performing real-time monitoring and analysis of telemetry data from the NASA Hubble Space Telescope (HST). In order to handle asynchronous inputs and perform in real time the system consists of three or more separate processes, which run concurrently and communicate via a message passing scheme. The data management process gathers, compresses, and scales the incoming telemetry data befoe sending it to the other tasks. The inferencing process uses the incoming data to perform a real-time analysis of the state and health of the Space Telescope. The I/O process receives telemetry monitors from the data management process, updates its graphical displays in real time, and acts as the interface to the console operator. The three processes may run on the same or different computers. This system is currently under development and is being used to monitor testcases produced by the Bass Telemetry System in the Hardware/Software Integration Facility at Lockheed Missile and Space Co. in Sunnyvale, California.

  2. Real time estimates of GDP growth

    Groot, de E.A. (Bert); Franses, P.H.P.H.


    This paper describes the components of the EICIE, the Econometric Institute Current Indicator of the Economy. This measure concerns quarterly and annual growth of Dutch real Gross Domestic Product. The key component of our real-time forecasting model for Dutch quarterly GDP is weekly staffing

  3. Real time estimates of GDP growth

    E.A. de Groot (Bert); Ph.H.B.F. Franses (Philip Hans)


    textabstractThis paper describes the components of the EICIE, the Econometric Institute Current Indicator of the Economy. This measure concerns quarterly and annual growth of Dutch real Gross Domestic Product. The key component of our real-time forecasting model for Dutch quarterly GDP is weekly

  4. In vivo nuclear magnetic resonance imaging of myocardial perfusion using the paramagnetic contrast agent manganese gluconate.

    Schaefer, S; Lange, R A; Kulkarni, P V; Katz, J; Parkey, R W; Willerson, J T; Peshock, R M


    Previous nuclear magnetic resonance (NMR) imaging studies have indicated that coronary occlusion does not produce sufficient changes in standard tissue relaxation times to allow the detection of acute ischemia. To identify acute myocardial perfusion abnormalities, the use of the paramagnetic agent manganese gluconate combined with calcium gluconate (MnGlu/CaGlu) was investigated in canine models of acute coronary artery occlusion. In vitro studies showed that MnGlu/CaGlu was a more efficient relaxing agent than gadolinium-DTPA (relaxivity of 7.8 versus 5.1 s-1 mM-1) and demonstrated affinity for normal myocardium. The distribution of MnGlu/CaGlu as measured by manganese-54 tracer studies was proportional to myocardial blood flow in both normal and ischemic tissue. Hearts excised from dogs after coronary artery occlusion and administration of 0.035 mM/kg MnGlu/CaGlu were imaged ex vivo using a relatively spin-lattice relaxation time (T1)-weighted gradient reversal technique (repetition time [TR] 50 ms and echo time [TE] 9 ms). These images showed increased signal intensity in the normally perfused myocardium with a mean signal intensity ratio of hypoperfused to normal myocardium of 0.55 +/- 0.12 (mean +/- SD). In vivo images obtained in nine dogs after coronary artery occlusion and administration of the same dose of MnGlu/CaGlu demonstrated the region of hypoperfused myocardium in six dogs with a signal intensity ratio of hypoperfused to normal myocardium of 0.64 +/- 0.23 (p less than 0.05 versus control). When a higher dose of 0.1 mM/kg MnGlu/CaGlu was utilized and in vivo imaging was performed using a relatively spin-spin relaxation time (T2)-weighted (TR gated, TE 60 ms) spin-echo sequence in six dogs, the signal intensity of normal myocardium was decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. System Equivalent for Real Time Digital Simulator

    Lin, Xi


    The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.

  6. Real time processor for array speckle interferometry

    Chin, Gordon; Florez, Jose; Borelli, Renan; Fong, Wai; Miko, Joseph; Trujillo, Carlos


    The authors are constructing a real-time processor to acquire image frames, perform array flat-fielding, execute a 64 x 64 element two-dimensional complex FFT (fast Fourier transform) and average the power spectrum, all within the 25 ms coherence time for speckles at near-IR (infrared) wavelength. The processor will be a compact unit controlled by a PC with real-time display and data storage capability. This will provide the ability to optimize observations and obtain results on the telescope rather than waiting several weeks before the data can be analyzed and viewed with offline methods. The image acquisition and processing, design criteria, and processor architecture are described.

  7. Real Time Radiation Exposure And Health Risks

    Hu, Shaowen; Barzilla, Janet E.; Semones, Edward J.


    Radiation from solar particle events (SPEs) poses a serious threat to future manned missions outside of low Earth orbit (LEO). Accurate characterization of the radiation environment in the inner heliosphere and timely monitoring the health risks to crew are essential steps to ensure the safety of future Mars missions. In this project we plan to develop an approach that can use the particle data from multiple satellites and perform near real-time simulations of radiation exposure and health risks for various exposure scenarios. Time-course profiles of dose rates will be calculated with HZETRN and PDOSE from the energy spectrum and compositions of the particles archived from satellites, and will be validated from recent radiation exposure measurements in space. Real-time estimation of radiation risks will be investigated using ARRBOD. This cross discipline integrated approach can improve risk mitigation by providing critical information for risk assessment and medical guidance to crew during SPEs.

  8. Real-Time Watercolor for Animation

    Thomas Luft; Oliver Deussen


    We present algorithms that allow for real-time rendering of 3D-scenes with a watercolor painting appearance. Our approach provides an appropriate simplification of the visual complexity, imitates characteristic natural effects of watercolor, and provides two essential painting techniques: the wet-on-wet and the wet-on-dry painting. We concentrate on efficient algorithms based on image space processing rather than on an exact simulation. This allows for the real-time rendering of 3D-scenes. During an animation a high frame-to-frame coherence can be achieved due to a stable segmentation scheme. Finally, we seamlessly integrate a smooth illumination into the watercolor renderings using information from the 3D-scene.

  9. Monte Carlo study of real time dynamics

    Alexandru, Andrei; Bedaque, Paulo F; Vartak, Sohan; Warrington, Neill C


    Monte Carlo studies involving real time dynamics are severely restricted by the sign problem that emerges from highly oscillatory phase of the path integral. In this letter, we present a new method to compute real time quantities on the lattice using the Schwinger-Keldysh formalism via Monte Carlo simulations. The key idea is to deform the path integration domain to a complex manifold where the phase oscillations are mild and the sign problem is manageable. We use the previously introduced "contraction algorithm" to create a Markov chain on this alternative manifold. We substantiate our approach by analyzing the quantum mechanical anharmonic oscillator. Our results are in agreement with the exact ones obtained by diagonalization of the Hamiltonian. The method we introduce is generic and in principle applicable to quantum field theory albeit very slow. We discuss some possible improvements that should speed up the algorithm.

  10. Real time PCR. Application in dengue studies

    Jeanette Prada-Arismendy


    Full Text Available PCR (polymerase chain reaction is a routinely used tool in every diagnostic and research laboratory. This technique has been used in detection of mutations and pathogens, forensic investigation, and even is the base tool for human genome sequencing. A modification of PCR technique, real time PCR, allows the quantification of nucleic acids with higher sensibility, specificity and reproducibility. This article is intended to clarify the foundations of real-time PCR, using an application model for virology. In the actual work, it was quantified the viral load of dengue virus serotype 2 produced from infected murine macrophages; the obtained results in this work established that murine strain BALB/c presents a greater susceptibility to dengue virus infection, which establishes BALB/c murine strain as a best model of study for investigation of dengue virus infection physiopathology.

  11. AMON: Transition to real-time operations

    Cowen, D. F.; Keivani, A.; Tešić, G.


    The Astrophysical Multimessenger Observatory Network (AMON) will link the world's leading high-energy neutrino, cosmic-ray, gamma-ray and gravitational wave observatories by performing real-time coincidence searches for multimessenger sources from observatories' subthreshold data streams. The resulting coincidences will be distributed to interested parties in the form of electronic alerts for real-time follow-up observation. We will present the science case, design elements, current and projected partner observatories, status of the AMON project, and an initial AMON-enabled analysis. The prototype of the AMON server has been online since August 2014 and processing archival data. Currently, we are deploying new high-uptime servers and will be ready to start issuing alerts as early as winter 2015/16.

  12. Collecting data in real time with postcards


    The success of information technology (IT) in transforming healthcare is often limited by the lack of clear understanding of the context at which the technology is used. Various methods have been proposed to understand healthcare context better in designing and implementing Health Information...... Systems. These methods often involve cross-sectional, retrospective data collection. This paper describes the postcard method for prospective real-time data collection, both in paper format and electronic format. This paper then describes the results obtained using postcard techniques in Denmark...... and Australia. The benefits of this technique are illustrated. There are limitations in using postcard techniques and this paper provides a detail discussion about these limitations. Postcard techniques provide unique advantages in understanding real time healthcare context and it is an important technique...

  13. Real Time Radiation Monitoring Using Nanotechnology

    Li, Jing (Inventor); Wilkins, Richard T. (Inventor); Hanratty, James J. (Inventor); Lu, Yijiang (Inventor)


    System and method for monitoring receipt and estimating flux value, in real time, of incident radiation, using two or more nanostructures (NSs) and associated terminals to provide closed electrical paths and to measure one or more electrical property change values .DELTA.EPV, associated with irradiated NSs, during a sequence of irradiation time intervals. Effects of irradiation, without healing and with healing, of the NSs, are separately modeled for first order and second order healing. Change values.DELTA.EPV are related to flux, to cumulative dose received by NSs, and to radiation and healing effectivity parameters and/, associated with the NS material and to the flux. Flux and/or dose are estimated in real time, based on EPV change values, using measured .DELTA.EPV values. Threshold dose for specified changes of biological origin (usually undesired) can be estimated. Effects of time-dependent radiation flux are analyzed in pre-healing and healing regimes.

  14. Real time gamma-ray signature identifier

    Rowland, Mark [Alamo, CA; Gosnell, Tom B [Moraga, CA; Ham, Cheryl [Livermore, CA; Perkins, Dwight [Livermore, CA; Wong, James [Dublin, CA


    A real time gamma-ray signature/source identification method and system using principal components analysis (PCA) for transforming and substantially reducing one or more comprehensive spectral libraries of nuclear materials types and configurations into a corresponding concise representation/signature(s) representing and indexing each individual predetermined spectrum in principal component (PC) space, wherein an unknown gamma-ray signature may be compared against the representative signature to find a match or at least characterize the unknown signature from among all the entries in the library with a single regression or simple projection into the PC space, so as to substantially reduce processing time and computing resources and enable real-time characterization and/or identification.

  15. Evaluation of left ventricular strain by real-time three-dimensional speckle tracking echocardiography in patients with hypertension and myocardial hypertrophy%实时三维超声心动图斑点追踪技术测量高血压心肌肥厚患者收缩期左室心肌应变

    汤乔颖; 邓又斌; 黄润青; 刘琨; 孙杰; 邓琪


    Objective To investigate left ventricular (LV) strain in patients with hypertension (HT)and myocardial hypertrophy using three-dimensional speckle tracking echocardiography.Methods Myocardial movement was analyzed in 37 primary HT patients with myocardial hypertrophy and 27 healthy volunteers.LV longitudinal,circumferential,radial and area strains were measured.The correlation between each global strain parameter and LV ejection fraction (LVEF) was analyzed.Results LV global longitudinal strain(GSL),global radial strain (GSR) and global area strain (GSA) of HT patients with myocardial hypertrophy were significantly lower than the contrast group,whereas global circumferential strain(GSC) showed no significant difference between the two groups.Longitudinal,radial and area strains were decreased in LV basal and middle levels,while decreased circumferential strain was detected only in basal level.There were significant correlations between LVEF and GSL,GSC,GSR,GSA.Conclusions Impairment of LV regional myocardial contractility can be detected by three-dimensional speckle tracking echocardiography.%目的 采用实时三维超声心动图斑点追踪技术研究原发性高血压心肌肥厚患者的收缩期左室心肌应变特点.方法 采用三维超声心动图斑点追踪技术对37例原发性高血压心肌肥厚患者及27例健康志愿者进行了室壁运动分析,测量左室纵向、圆周向、径向、面积应变,比较两组间各应变参数的差异,并分析各项整体应变参数与左室射血分数(LVEF)的相关性.结果 高血压心肌肥厚患者的左室整体纵向、径向和面积应变较正常对照组明显减低,左室整体圆周向应变与对照组间无明显差异.纵向、径向、圆周向应变在左室基底段、中段明显减低,圆周向应变减低仅见于基底段.左室整体纵向、圆周向、径向、面积应变与LVEF具有相关性.结论 实时三维超声心动图斑点追踪技术可检测到高血压心

  16. "Fast" Is Not "Real-Time": Designing Effective Real-Time AI Systems

    O'Reilly, Cindy A.; Cromarty, Andrew S.


    Realistic practical problem domains (such as robotics, process control, and certain kinds of signal processing) stand to benefit greatly from the application of artificial intelligence techniques. These problem domains are of special interest because they are typified by complex dynamic environments in which the ability to select and initiate a proper response to environmental events in real time is a strict prerequisite to effective environmental interaction. Artificial intelligence systems developed to date have been sheltered from this real-time requirement, however, largely by virtue of their use of simplified problem domains or problem representations. The plethora of colloquial and (in general) mutually inconsistent interpretations of the term "real-time" employed by workers in each of these domains further exacerbates the difficul-ties in effectively applying state-of-the-art problem solving tech-niques to time-critical problems. Indeed, the intellectual waters are by now sufficiently muddied that the pursuit of a rigorous treatment of intelligent real-time performance mandates the redevelopment of proper problem perspective on what "real-time" means, starting from first principles. We present a simple but nonetheless formal definition of real-time performance. We then undertake an analysis of both conventional techniques and AI technology with respect to their ability to meet substantive real-time performance criteria. This analysis provides a basis for specification of problem-independent design requirements for systems that would claim real-time performance. Finally, we discuss the application of these design principles to a pragmatic problem in real-time signal understanding.

  17. Real-time optical information processing

    Javidi, Bahram


    Real-Time Optical Information Processing covers the most recent developments in optical information processing, pattern recognition, neural computing, and materials for devices in optical computing. Intended for researchers and graduate students in signal and information processing with some elementary background in optics, the book provides both theoretical and practical information on the latest in information processing in all its aspects. Leading researchers in the field describe the significant signal processing algorithms architectures in optics as well as basic hardware concepts,

  18. Real-Time Neutron Radiography at CARR

    HE; Lin-feng; HAN; Song-bai; WANG; Hong-li; WU; Mei-mei; WEI; Guo-hai; WANG; Yu


    <正>A real-time detector system for neutron radiography based on CMOS camera has been designed for the thermal neutron imaging facility under construction at China Advanced Research Reactor (CARR). This system is equipped with a new scientific CMOS camera with 5.5 million pixels and speed up to 100 fps at full frame. The readout noise is less than 2.4 electron per pixel. It is capable of providing

  19. Robust synthesis for real-time systems

    Larsen, Kim Guldstrand; Legay, Axel; Traonouez, Louis-Marie;


    Specification theories for real-time systems allow reasoning about interfaces and their implementation models, using a set of operators that includes satisfaction, refinement, logical and parallel composition. To make such theories applicable throughout the entire design process from an abstract ...... strategies in timed games. Finally, we consider the parametric robustness problem and propose a counter-example refinement heuristic for computing safe perturbation values....

  20. Real-time RGBD SLAM system

    Czupryński, BłaŻej; Strupczewski, Adam


    A real-time tracking and mapping SLAM system is presented. The developed system uses input from an RGBD sensor and tracks the camera pose from frame to frame. The tracking is based on matched feature points and is performed with respect to selected keyframes. The system is robust and scalable, as an arbitrary number of keyframes can be chosen for visualization and tracking depending on the desired accuracy and speed. The presented system is also a good platform for further research.

  1. Boundary Correct Real-Time Soft Shadows

    Jacobsen, Bjarke; Christensen, Niels Jørgen; Larsen, Bent Dalgaard


    This paper describes a method to determine correct shadow boundaries from an area light source using umbra and penumbra volumes. The light source is approximated by a circular disk as this gives a fast way to extrude the volumes. The method also gives a crude estimate of the visibility of the are...... for implementation on most programmable hardware. Though some crude approximations are used in the visibility function, the method can be used to produce soft shadows with correct boundaries in real time....

  2. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    Hansen, Thomas Fritz; Dirks, Christina G; Jensen, Gorm B;


    PURPOSE: To investigate the diagnostic ability of quantitative magnetic resonance imaging (MRI) heart perfusion in acute heart patients, a fast, multislice dynamic contrast-enhanced MRI sequence was applied to patients with acute myocardial infarction. MATERIALS AND METHODS: Seven patients...... slices, each having 60 sectors, provided an estimation of the severity and extent of the perfusion deficiency. Reperfusion was assessed both by noninvasive criteria and by coronary angiography (CAG). RESULTS: The Ki maps clearly delineated the infarction in all patients. Thrombolytic treatment...... was clearly beneficial in one case, but had no effect in the two other cases. Over the time-course of the study, normal perfusion values were not reestablished following thrombolytic treatment in all cases investigated. CONCLUSION: This study shows that quantitative MRI perfusion values can be obtained from...

  3. Real Time Route for Dynamic Road Congestions

    A. M. Riad


    Full Text Available Minimizing service delivery and travel time during rush hours downtown is strategic target for several organizations, especially the emergency organizations. This paper presents an On-line and Real-time Dynamic Route System (ORDRS which benefits from the advantages and integration between information system and communications technology. It utilizes Global Positioning System (GPS, Geographical Information Systems (GIS, and Global System for Mobile communications (GSM; for producing the real time routes for vehicles. GPS-Tracker is the main input device for ORDRS. It is fixated in a vehicle, sends vehicle's movement data (Geo-info to the control center wirelessly through either Short Message Service (SMS or General Packet Radio Service (GPRS. Geo-info includes time, date, longitude, latitude, speed, and etc., these data is classified over time during weekdays into interval time slices, each slice is 30 minutes. Speeds are treated by GIS tools to determine historical and real time speeds for each street segment in the road network which is being used for calculating time impedance (cost matrix for each street segment dynamically. ORDRS uses a cost matrix of the current time slice for determining the best route to each vehicle in duty attached. Several algorithms was used to calculate the shortest route, a comparison between Dijekstra and Yen algorithms was studied.

  4. The IGS Real-Time Service

    Caissy, Mark; Agrotis, Loukis; Weber, Georg; Fisher, Steven


    The IGS Real-Time Service (RTS) is being rolled out in 2013 following the successful completion of the IGS Real-Time Pilot Project. The RTS has recently completed beta testing and is now operating at the level of initial operating capability. The service will reach full operating capability by the end of 2013. RTS products include GNSS data streams and GNSS orbit and clock correction streams. These products are available in real-time in accordance with the IGS open-data policy using RTCM standard formats and the NTRIP transportation protocol. The RTS is key to IGS's support of the GGOS Natural Hazards theme. Of particular importance in this context is the high degree of redundancy that is build into the RTS in order to reliably support public-good scientific applications commonly associated with natural hazards; for example, precise-point positioning applications requiring high accuracy and low latency related to earthquakes and tsunamis . This presentation will illustrate the data gathering through product generation to user distribution design of the RTS, highlighting built-in robustness at various stages. The presentation will also present an assessment of the performance of the service to date.

  5. Real-time Interactive Tree Animation.

    Quigley, Ed; Yu, Yue; Huang, Jingwei; Lin, Winnie; Fedkiw, Ronald


    We present a novel method for posing and animating botanical tree models interactively in real time. Unlike other state of the art methods which tend to produce trees that are overly flexible, bending and deforming as if they were underwater plants, our approach allows for arbitrarily high stiffness while still maintaining real-time frame rates without spurious artifacts, even on quite large trees with over ten thousand branches. This is accomplished by using an articulated rigid body model with as-stiff-as-desired rotational springs in conjunction with our newly proposed simulation technique, which is motivated both by position based dynamics and the typical O(N) algorithms for articulated rigid bodies. The efficiency of our algorithm allows us to pose and animate trees with millions of branches or alternatively simulate a small forest comprised of many highly detailed trees. Even using only a single CPU core, we can simulate ten thousand branches in real time while still maintaining quite crisp user interactivity. This has allowed us to incorporate our framework into a commodity game engine to run interactively even on a low-budget tablet. We show that our method is amenable to the incorporation of a large variety of desirable effects such as wind, leaves, fictitious forces, collisions, fracture, etc.

  6. Comparison of gadolinium polylysine and gadopentetate in contrast enhanced MR imaging of myocardial ischemia-reperfusion in cats

    Lim, Tae Hwan [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Jung Hee; Lee, Tae Keun; Mun, Chi Woong [Asan Institute for Life Sciences, Seoul (Korea, Republic of)


    To assess the signal enhancement by gadolinium-DTPA-polylysine (Gd-polylysine) as compared to gadopentetate (Gd-DTPA) in MR imaging of heart that have undergone ischemia-reperfusion, and to estimate the extent of myocardial damage covered by the MR signal enhancement. A series of contrast enhanced cardiac MR images were obtained from 17 cats subjected to a 90 minutes of occlusion of the left anterior descending coronary artery (LAD) followed by a 90 minutes of reperfusion. Time courses of changes in the signal intensity (SI) of the ischemic area were measured in Gd-polylysine group (8 cats) and Gd-DTPA group (9 cats). The size of MR signal enhanced area was then compared to the sizes of infarction and the area at risk revealed by TTC histochemical staining. Maximum SIs were obtained at 60 minutes and 30 minutes after injection of the contrast material, respectively for Gd-polylysine group and Gd-DTPA group. Signal enhancement was stronger and persistent for a longer period in Gd-polylysine group than in GD-DTPA group. Sizes of the enhanced are, the infarction, and the area at risk were about 30%, 15%, and 50% of the total left ventricle (LV) area; the difference between the groups was statistically insignificant. Gd-polylysine can be used better for a blood pool marker than Gd-DTPA in MR imaging of myocardial ischemia, due to its strong and persistent signal enhancement. The MR signal enhanced area includes both the infarcted area and a portion of the area at risk.

  7. Kinetic Measurement and Real Time Visualization of Somatic Reprogramming.

    Quintanilla, Rene H; Asprer, Joanna; Sylakowski, Kyle; Lakshmipathy, Uma


    Somatic reprogramming has enabled the conversion of adult cells to induced pluripotent stem cells (iPSC) from diverse genetic backgrounds and disease phenotypes. Recent advances have identified more efficient and safe methods for introduction of reprogramming factors. However, there are few tools to monitor and track the progression of reprogramming. Current methods for monitoring reprogramming rely on the qualitative inspection of morphology or staining with stem cell-specific dyes and antibodies. Tools to dissect the progression of iPSC generation can help better understand the process under different conditions from diverse cell sources. This study presents key approaches for kinetic measurement of reprogramming progression using flow cytometry as well as real-time monitoring via imaging. To measure the kinetics of reprogramming, flow analysis was performed at discrete time points using antibodies against positive and negative pluripotent stem cell markers. The combination of real-time visualization and flow analysis enables the quantitative study of reprogramming at different stages and provides a more accurate comparison of different systems and methods. Real-time, image-based analysis was used for the continuous monitoring of fibroblasts as they are reprogrammed in a feeder-free medium system. The kinetics of colony formation was measured based on confluence in the phase contrast or fluorescence channels after staining with live alkaline phosphatase dye or antibodies against SSEA4 or TRA-1-60. The results indicated that measurement of confluence provides semi-quantitative metrics to monitor the progression of reprogramming.

  8. Exploring Earthquakes in Real-Time

    Bravo, T. K.; Kafka, A. L.; Coleman, B.; Taber, J. J.


    Earthquakes capture the attention of students and inspire them to explore the Earth. Adding the ability to view and explore recordings of significant and newsworthy earthquakes in real-time makes the subject even more compelling. To address this opportunity, the Incorporated Research Institutions for Seismology (IRIS), in collaboration with Moravian College, developed ';jAmaSeis', a cross-platform application that enables students to access real-time earthquake waveform data. Students can watch as the seismic waves are recorded on their computer, and can be among the first to analyze the data from an earthquake. jAmaSeis facilitates student centered investigations of seismological concepts using either a low-cost educational seismograph or streamed data from other educational seismographs or from any seismic station that sends data to the IRIS Data Management System. After an earthquake, students can analyze the seismograms to determine characteristics of earthquakes such as time of occurrence, distance from the epicenter to the station, magnitude, and location. The software has been designed to provide graphical clues to guide students in the analysis and assist in their interpretations. Since jAmaSeis can simultaneously record up to three stations from anywhere on the planet, there are numerous opportunities for student driven investigations. For example, students can explore differences in the seismograms from different distances from an earthquake and compare waveforms from different azimuthal directions. Students can simultaneously monitor seismicity at a tectonic plate boundary and in the middle of the plate regardless of their school location. This can help students discover for themselves the ideas underlying seismic wave propagation, regional earthquake hazards, magnitude-frequency relationships, and the details of plate tectonics. The real-time nature of the data keeps the investigations dynamic, and offers students countless opportunities to explore.

  9. Real-time image and video processing

    Kehtarnavaz, Nasser


    This book presents an overview of the guidelines and strategies for transitioning an image or video processing algorithm from a research environment into a real-time constrained environment. Such guidelines and strategies are scattered in the literature of various disciplines including image processing, computer engineering, and software engineering, and thus have not previously appeared in one place. By bringing these strategies into one place, the book is intended to serve the greater community of researchers, practicing engineers, industrial professionals, who are interested in taking an im

  10. Linear Regression Based Real-Time Filtering

    Misel Batmend


    Full Text Available This paper introduces real time filtering method based on linear least squares fitted line. Method can be used in case that a filtered signal is linear. This constraint narrows a band of potential applications. Advantage over Kalman filter is that it is computationally less expensive. The paper further deals with application of introduced method on filtering data used to evaluate a position of engraved material with respect to engraving machine. The filter was implemented to the CNC engraving machine control system. Experiments showing its performance are included.

  11. Object detection in real-time

    Solder, Ulrich; Graefe, Volker


    An algorithm working on monocular gray-scale image sequences for object detection combined with a road tracker is presented. This algorithm appropriate for the real-time demands of an autonomous car driving with speeds over 40 km/h may be used for triggering obstacle avoidance maneuvers such as coming to a safe stop automatically in front of an obstacle or following another car. Moving and static objects have been detected in real-world experiments on various types of roads even under unfavorable weather conditions. . Morgenthaler and

  12. CUDA-based real time surgery simulation.

    Liu, Youquan; De, Suvranu


    In this paper we present a general software platform that enables real time surgery simulation on the newly available compute unified device architecture (CUDA)from NVIDIA. CUDA-enabled GPUs harness the power of 128 processors which allow data parallel computations. Compared to the previous GPGPU, it is significantly more flexible with a C language interface. We report implementation of both collision detection and consequent deformation computation algorithms. Our test results indicate that the CUDA enables a twenty times speedup for collision detection and about fifteen times speedup for deformation computation on an Intel Core 2 Quad 2.66 GHz machine with GeForce 8800 GTX.

  13. Real-time inclinometer using accelerometer MEMS

    Hanto, D; Hermanto, B; Puranto, P; Handoko, L T


    A preliminary design of inclinometer for real-time monitoring system of soil displacement is proposed. The system is developed using accelerometer sensor with microelectromechanical system (MEMS) device. The main apparatus consists of a single MEMS sensor attached to a solid pipe and stucked pependicularly far away below the soil surface. The system utilizes small fractions of electrical signals from MEMS sensor induced by the pipe inclination due to soil displacements below the surface. It is argued that the system is accurate enough to detect soil displacements responsible for landslides, and then realizes a simple and low cost landslide early warning system.

  14. Systems Analyze Water Quality in Real Time


    A water analyzer developed under Small Business Innovation Research (SBIR) contracts with Kennedy Space Center now monitors treatment processes at water and wastewater facilities around the world. Originally designed to provide real-time detection of nutrient levels in hydroponic solutions for growing plants in space, the ChemScan analyzer, produced by ASA Analytics Inc., of Waukesha, Wisconsin, utilizes spectrometry and chemometric algorithms to automatically analyze multiple parameters in the water treatment process with little need for maintenance, calibration, or operator intervention. The company has experienced a compound annual growth rate of 40 percent over its 15-year history as a direct result of the technology's success.

  15. Testing Real-Time Systems Using UPPAAL

    Hessel, Anders; Larsen, Kim Guldstrand; Mikucionis, Marius


    This chapter presents principles and techniques for model-based black-box conformance testing of real-time systems using the Uppaal model-checking tool-suite. The basis for testing is given as a network of concurrent timed automata specified by the test engineer. Relativized input....../output conformance serves as the notion of implementation correctness, essentially timed trace inclusion taking environment assumptions into account. Test cases can be generated offline and later executed, or they can be generated and executed online. For both approaches this chapter discusses how to specify test...... objectives, derive test sequences, apply these to the system under test, and assign a verdict....

  16. Real-time detection of gravitational microlensing

    Pratt, M R; Axelrod, T S; Becker, A; Bennett, D P; Cook, K H; Freeman, K C; Griest, K; Guern, J A; Lehner, M; Marshall, S L; Peterson, B A; Quinn, P J; Reiss, D; Rodgers, A W; Stubbs, C W; Sutherland, W; Welch, D


    Real-time detection of microlensing has moved from proof of concept in 1994 to a steady stream of events this year. Global dissemination of these events by the MACHO and OGLE collaborations has made possible intensive photometric and spectroscopic followup from widely dispersed sites confirming the microlensing hypothesis. Improved photometry and increased temporal resolution from followup observations greatly increases the possibility of detecting deviations from the standard point-source, point-lens, inertial motion microlensing model. These deviations are crucial in understanding individual lensing systems by breaking the degeneracy between lens mass, position and velocity. We report here on GMAN (Global Microlensing Alert Network), the coordinated followup of MACHO alerts.

  17. Low cost real time interactive analysis system

    Stetina, F.


    Efforts continue to develop a low cost real time interactive analysis system for the reception of satellite data. A multi-purpose ingest hardware software frame formatter was demonstrated for GOES and TIROS data and work is proceeding on extending the capability to receive GMS data. A similar system was proposed as an archival and analysis system for use with INSAT data and studies are underway to modify the system to receive the planned SeaWiFS (ocean color) data. This system was proposed as the core of a number of international programs in support of U.S. AID activities. Systems delivered or nearing final testing are listed.

  18. Association between diffuse myocardial fibrosis by cardiac magnetic resonance contrast-enhanced T(1) mapping and subclinical myocardial dysfunction in diabetic patients: a pilot study.

    Ng, A.C.; Auger, D.; Delgado, V.; Elderen, S.G. van; Bertini, M.; Siebelink, H.M.; Geest, R.J. van der; Bonetti, C.; Velde, E.T. van der; Roos, A. de; Smit, J.W.A.; Leung, D.Y.; Bax, J.J.; Lamb, H.J.


    BACKGROUND: Diabetic patients have increased interstitial myocardial fibrosis on histological examination. Magnetic resonance imaging (MRI) T(1) mapping is a previously validated imaging technique that can quantify the burden of global and regional interstitial fibrosis. However, the association bet

  19. Real time water chemistry monitoring and diagnostics

    Gaudreau, T.M.; Choi, S.S. [EPRIsolutions, Palo Alto, CA (United States)


    EPRI has produced a real time water chemistry monitoring and diagnostic system. This system is called SMART ChemWorks and is based on the EPRI ChemWorks codes. System models, chemistry parameter relationships and diagnostic approaches from these codes are integrated with real time data collection, an intelligence engine and Internet technologies to allow for automated analysis of system chemistry. Significant data management capabilities are also included which allow the user to evaluate data and create automated reporting. Additional features have been added to the system in recent years including tracking and evaluation of primary chemistry as well as the calculation and tracking of primary to secondary leakage in PWRs. This system performs virtual sensing, identifies normal and upset conditions, and evaluates the consistency of on-line monitor and grab sample readings. The system also makes use of virtual fingerprinting to identify the cause of any chemistry upsets. This technology employs plant-specific data and models to determine the chemical state of the steam cycle. (authors)

  20. Video Surveillance for Real Time Objects

    N.R. Raajan


    Full Text Available In this study, we describe an integrated solution for video surveillance in a fortified environment. The focus of this study is on identification of real time objects on different environments. The system is composed of robust object detection module, which normally detects the presence of abandoned objects, concealed objects hidden inside the human clothing, objects in dark environment and performs image segmentation with the intention of facilitating human operator’s task of retrieving the cause of a buzzer. The abandoned objects are detected by image segmentation based on temporal rank order filtering. Image fusion technique which fuses a color visual image and a corresponding IR image for concealed objects in guarded environment and in some cases like dark environment heat signature can be used for detecting real time objects etc. In the clips of interest, the key frame is the one depicting a person leaving a dangerous object and is determined on the basis of a feature indicating the movement around the dangerous region.

  1. Real-time PCR in microfluidic devices

    Becker, Holger; Hlawatsch, Nadine; Klemm, Richard; Moche, Christian; Hansen-Hagge, Thomas; Gärtner, Claudia


    A central method in a standard biochemical laboratory is represented by the polymerase chain reaction (PCR), therefore many attempts have been performed so far to implement this technique in lab-on-a-chip (LOC) devices. PCR is an ideal candidate for miniaturization because of a reduction of assay time and decreased costs for expensive bio-chemicals. In case of the "classical" PCR, detection is done by identification of DNA fragments electrophoretically separated in agarose gels. This method is meanwhile frequently replaced by the so-called Real-Time-PCR because here the exponential increase of amplificates can be observed directly by measurement of DNA interacting fluorescent dyes. Two main methods for on-chip PCRs are available: traditional "batch" PCR in chambers on a chip using thermal cycling, requiring about 30 minutes for a typical PCR protocol and continuous-flow PCR, where the liquid is guided over stationary temperature zones. In the latter case, the PCR protocol can be as fast as 5 minutes. In the presented work, a proof of concept is demonstrated for a real-time-detection of PCR products in microfluidic systems.

  2. Integrated real-time roof monitoring

    SHEN Bao-tang; GUO Hua; KING Andrew


    CSIRO has recently developed a real-time roof monitoring system for under-ground coal mines and successfully tried the system in gate roads at Ulan Mine. The sys-tem integrated displacement monitoring, stress monitoring and seismic monitoring in one package. It included GEL multianchor extensometers, vibrating wire uniaxial stress meters, ESG seismic monitoring system with microseismic sensors and high-frequency AE sen-sors. The monitoring system automated and the data can be automatically collected by a central computer located in an underground nonhazardous area. The data are then trans-ferred to the surface via an optical fiber cable. The real-time data were accessed at any location with an Internet connection. The trials of the system in two tailgates at Ulan Mine demonstrate that the system is effective for monitoring the behavior and stability of read-ways during Iongwall mining. The continuous roof displacement/stress data show clear precursors of roof falls. The seismic data (event count and locations) provide insights into the roof failure process during roof fall.

  3. An efficient real time superresolution ASIC system

    Reddy, Dikpal; Yue, Zhanfeng; Topiwala, Pankaj


    Superresolution of images is an important step in many applications like target recognition where the input images are often grainy and of low quality due to bandwidth constraints. In this paper, we present a real-time superresolution application implemented in ASIC/FPGA hardware, and capable of 30 fps of superresolution by 16X in total pixels. Consecutive frames from the video sequence are grouped and the registered values between them are used to fill the pixels in the higher resolution image. The registration between consecutive frames is evaluated using the algorithm proposed by Schaum et al. The pixels are filled by averaging a fixed number of frames associated with the smallest error distances. The number of frames (the number of nearest neighbors) is a user defined parameter whereas the weights in the averaging process are decided by inverting the corresponding smallest error distances. Wiener filter is used to post process the image. Different input parameters, such as size of input image, enlarging factor and the number of nearest neighbors, can be tuned conveniently by the user. We use a maximum word size of 32 bits to implement the algorithm in Matlab Simulink as well as the hardware, which gives us a fine balance between the number of bits and performance. The algorithm performs with real time speed with very impressive superresolution results.


    V. Karthikeyan


    Full Text Available Memory fragmentation is the development of a large number of separate free areas. Memory management in embedded systems demand effective implementation schemes to avoid fragmentation problem. Existing dynamic memory allocation methods fail to suit real time system requirements. Execution times need to be deterministic and this motivates the need for allocation and deallocation to be done in constant time with the help of API’s. In µC/OS-II, memory allocation is semi-dynamic and a buddy allocator dynamic memory allocation algorithm is commonly used. Programmer must statically allocate a memory and partition the region using µC/OS-II Kernel API. Tasks can only request pre-partitioned fixed-size memory space from µC/OS-II. Memory allocation times are influenced by the ratio of memory allocation to the stack size of the task. In this research work memory management in LPC 1768 environment using RTOS µC/OS-II is proposed. Effective sharing of memory blocks among tasks co exists with partition. The captured results shows that the memory allocation and deallocation suits real time. The implication of the work is that, the necessity to reserve a static set of locations ahead of time is eliminated so that memory can be allocated at compile or design time.

  5. Highly-Accelerated Real-Time Cardiac Cine MRI Using k-t SPARSE-SENSE

    Feng, Li; Srichai, Monvadi B.; Lim, Ruth P.; Harrison, Alexis; King, Wilson; Adluru, Ganesh; Dibella, Edward VR.; Sodickson, Daniel K.; Otazo, Ricardo; Kim, Daniel


    For patients with impaired breath-hold capacity and/or arrhythmias, real-time cine MRI may be more clinically useful than breath-hold cine MRI. However, commercially available real-time cine MRI methods using parallel imaging typically yield relatively poor spatio-temporal resolution due to their low image acquisition speed. We sought to achieve relatively high spatial resolution (~2.5mm × 2.5mm) and temporal resolution (~40ms), to produce high-quality real-time cine MR images that could be applied clinically for wall motion assessment and measurement of left ventricular (LV) function. In this work, we present an 8-fold accelerated real-time cardiac cine MRI pulse sequence using a combination of compressed sensing and parallel imaging (k-t SPARSE-SENSE). Compared with reference, breath-hold cine MRI, our 8-fold accelerated real-time cine MRI produced significantly worse qualitative grades (1–5 scale), but its image quality and temporal fidelity scores were above 3.0 (adequate) and artifacts and noise scores were below 3.0 (moderate), suggesting that acceptable diagnostic image quality can be achieved. Additionally, both 8-fold accelerated real-time cine and breath-hold cine MRI yielded comparable LV function measurements, with coefficient of variation cine MRI with k-t SPARSE-SENSE is a promising modality for rapid imaging of myocardial function. PMID:22887290

  6. Highly accelerated real-time cardiac cine MRI using k-t SPARSE-SENSE.

    Feng, Li; Srichai, Monvadi B; Lim, Ruth P; Harrison, Alexis; King, Wilson; Adluru, Ganesh; Dibella, Edward V R; Sodickson, Daniel K; Otazo, Ricardo; Kim, Daniel


    For patients with impaired breath-hold capacity and/or arrhythmias, real-time cine MRI may be more clinically useful than breath-hold cine MRI. However, commercially available real-time cine MRI methods using parallel imaging typically yield relatively poor spatio-temporal resolution due to their low image acquisition speed. We sought to achieve relatively high spatial resolution (∼2.5 × 2.5 mm(2)) and temporal resolution (∼40 ms), to produce high-quality real-time cine MR images that could be applied clinically for wall motion assessment and measurement of left ventricular function. In this work, we present an eightfold accelerated real-time cardiac cine MRI pulse sequence using a combination of compressed sensing and parallel imaging (k-t SPARSE-SENSE). Compared with reference, breath-hold cine MRI, our eightfold accelerated real-time cine MRI produced significantly worse qualitative grades (1-5 scale), but its image quality and temporal fidelity scores were above 3.0 (adequate) and artifacts and noise scores were below 3.0 (moderate), suggesting that acceptable diagnostic image quality can be achieved. Additionally, both eightfold accelerated real-time cine and breath-hold cine MRI yielded comparable left ventricular function measurements, with coefficient of variation cine MRI with k-t SPARSE-SENSE is a promising modality for rapid imaging of myocardial function. Copyright © 2012 Wiley Periodicals, Inc.

  7. Real-Time and Near Real-Time Data for Space Weather Applications and Services

    Singer, H. J.; Balch, C. C.; Biesecker, D. A.; Matsuo, T.; Onsager, T. G.


    Space weather can be defined as conditions in the vicinity of Earth and in the interplanetary environment that are caused primarily by solar processes and influenced by conditions on Earth and its atmosphere. Examples of space weather are the conditions that result from geomagnetic storms, solar particle events, and bursts of intense solar flare radiation. These conditions can have impacts on modern-day technologies such as GPS or electric power grids and on human activities such as astronauts living on the International Space Station or explorers traveling to the moon or Mars. While the ultimate space weather goal is accurate prediction of future space weather conditions, for many applications and services, we rely on real-time and near-real time observations and model results for the specification of current conditions. In this presentation, we will describe the space weather system and the need for real-time and near-real time data that drive the system, characterize conditions in the space environment, and are used by models for assimilation and validation. Currently available data will be assessed and a vision for future needs will be given. The challenges for establishing real-time data requirements, as well as acquiring, processing, and disseminating the data will be described, including national and international collaborations. In addition to describing how the data are used for official government products, we will also give examples of how these data are used by both the public and private sector for new applications that serve the public.

  8. Memory controllers for real-time embedded systems predictable and composable real-time systems

    Akesson, Benny


      Verification of real-time requirements in systems-on-chip becomes more complex as more applications are integrated. Predictable and composable systems can manage the increasing complexity using formal verification and simulation.  This book explains the concepts of predictability and composability and shows how to apply them to the design and analysis of a memory controller, which is a key component in any real-time system. This book is generally intended for readers interested in Systems-on-Chips with real-time applications.   It is especially well-suited for readers looking to use SDRAM memories in systems with hard or firm real-time requirements. There is a strong focus on real-time concepts, such as predictability and composability, as well as a brief discussion about memory controller architectures for high-performance computing. Readers will learn step-by-step how to go from an unpredictable SDRAM memory, offering highly variable bandwidth and latency, to a predictable and composable shared memory...

  9. Evans blue staining of cardiomyocytes induced by myocardial contrast echocardiography in rats: evidence for necrosis instead of apoptosis.

    Miller, Douglas L; Li, Peng; Dou, Chunyan; Armstrong, William F; Gordon, David


    High mechanical index (MI) echocardiography with contrast agent has been shown to induce Evans blue staining of cardiomyocytes, seen 1 d after exposure, in addition to contraction band necrosis, seen immediately after exposure. This research examined the roles of necrosis vs. apoptosis in these bioeffects. Myocardial contrast echocardiography at high MI with 1:4 electrocardiogram triggering was performed in anesthetized rats at 1.5 MHz. Histologically observable cell injury was accumulated by infusing a high dose of 50 microL/kg ultrasound contrast media via tail vein for 5 min at the start of 10 min of scanning. Evans blue dye or propidium iodide was injected as an indicator of cardiomyocyte plasma membrane integrity. Histologic sections were stained using the terminal dUTP nick-end labeling (TUNEL) method for labeling nuclei with DNA degradation (e.g., apoptosis). Evans blue fluorescent cells were counted on frozen sections or on hematoxylin-stained and TUNEL-labeled paraffin sections. In addition, transmission electron microscopy was used to assess potential apoptotic nuclei. Hypercontraction and propidium iodide staining were observed immediately after imaging exposure. Although TUNEL-positive cells were evident after 4 h, these also had indications of contraction band necrosis, and features of apoptosis were not confirmed by electron microscopy. Inflammatory cell infiltration was evident after 24 h. A second, more subtle injury was recognized by Evans blue staining, with minimal inflammatory cell infiltration at the morphologically intact stained cells after 24 h. Apoptosis was not detected by the TUNEL method in the cardiomyocytes stained with Evans blue at 24 h. However, Evans blue-stained cell numbers declined after 48 h, with continued inflammatory cell infiltration. The initial insult for Evans blue-stained cardiomyocytes apparently induced partial permeability of the plasma membrane, which led to gradual degeneration (but not apoptosis) and necrosis


    Kristensen, Thomas Krogsgaard


    Dette er en afrapportering fra den årlige CONTRAST workshop, der i 2007 blev afholdt i Yaoundé, Cameroon.......Dette er en afrapportering fra den årlige CONTRAST workshop, der i 2007 blev afholdt i Yaoundé, Cameroon....

  11. Feedback as real-time constructions

    Keiding, Tina Bering; Qvortrup, Ane


    This article offers a re-description of feedback and the significance of time in feedback constructions based on systems theory. It describes feedback as internal, real-time constructions in a learning system. From this perspective, feedback is neither immediate nor delayed, but occurs in the very...... instant it takes place. This article argues for a clear distinction between the timing of communicative events, such as responses that are provided as help for feedback constructions, and the feedback construction itself as an event in a psychic system. Although feedback is described as an internal......, system-relative construction, different teaching environments offer diverse conditions for feedback constructions. The final section of this article explores this idea with the help of examples from both synchronous oral interaction and asynchronous text-based interaction mediated by digital media....

  12. Real Time Structured Light and Applications

    Wilm, Jakob

    Structured light scanning is a versatile method for 3D shape acquisition. While much faster than most competing measurement techniques, most high-end structured light scans still take in the order of seconds to complete. Low-cost sensors such as Microsoft Kinect and time of flight cameras have made...... 3D sensor ubiquitous and have resulted in a vast amount of new applications and methods. However, such low-cost sensors are generally limited in their accuracy and precision, making them unsuitable for e.g. accurate tracking and pose estimation. With recent improvements in projector technology......]. A high performance flexible open source software toolkit is presented [Contribution C], which makes real time scanning possible on commodity hardware. Further, an approach is presented to correct for motion artifacts in dynamic scenes [Contribution E]. An application for such systems is presented...

  13. Real-time, face recognition technology

    Brady, S.


    The Institute for Scientific Computing Research (ISCR) at Lawrence Livermore National Laboratory recently developed the real-time, face recognition technology KEN. KEN uses novel imaging devices such as silicon retinas developed at Caltech or off-the-shelf CCD cameras to acquire images of a face and to compare them to a database of known faces in a robust fashion. The KEN-Online project makes that recognition technology accessible through the World Wide Web (WWW), an internet service that has recently seen explosive growth. A WWW client can submit face images, add them to the database of known faces and submit other pictures that the system tries to recognize. KEN-Online serves to evaluate the recognition technology and grow a large face database. KEN-Online includes the use of public domain tools such as mSQL for its name-database and perl scripts to assist the uploading of images.

  14. Near real-time stereo vision system

    Anderson, Charles H. (Inventor); Matthies, Larry H. (Inventor)


    The apparatus for a near real-time stereo vision system for use with a robotic vehicle is described. The system is comprised of two cameras mounted on three-axis rotation platforms, image-processing boards, a CPU, and specialized stereo vision algorithms. Bandpass-filtered image pyramids are computed, stereo matching is performed by least-squares correlation, and confidence ranges are estimated by means of Bayes' theorem. In particular, Laplacian image pyramids are built and disparity maps are produced from the 60 x 64 level of the pyramids at rates of up to 2 seconds per image pair. The first autonomous cross-country robotic traverses (of up to 100 meters) have been achieved using the stereo vision system of the present invention with all computing done onboard the vehicle. The overall approach disclosed herein provides a unifying paradigm for practical domain-independent stereo ranging.

  15. Kalman Filtering with Real-Time Applications

    Chui, Charles K


    Kalman Filtering with Real-Time Applications presents a thorough discussion of the mathematical theory and computational schemes of Kalman filtering. The filtering algorithms are derived via different approaches, including a direct method consisting of a series of elementary steps, and an indirect method based on innovation projection. Other topics include Kalman filtering for systems with correlated noise or colored noise, limiting Kalman filtering for time-invariant systems, extended Kalman filtering for nonlinear systems, interval Kalman filtering for uncertain systems, and wavelet Kalman filtering for multiresolution analysis of random signals. Most filtering algorithms are illustrated by using simplified radar tracking examples. The style of the book is informal, and the mathematics is elementary but rigorous. The text is self-contained, suitable for self-study, and accessible to all readers with a minimum knowledge of linear algebra, probability theory, and system engineering.

  16. Real time speech formant analyzer and display

    Holland, George E. (Ames, IA); Struve, Walter S. (Ames, IA); Homer, John F. (Ames, IA)


    A speech analyzer for interpretation of sound includes a sound input which converts the sound into a signal representing the sound. The signal is passed through a plurality of frequency pass filters to derive a plurality of frequency formants. These formants are converted to voltage signals by frequency-to-voltage converters and then are prepared for visual display in continuous real time. Parameters from the inputted sound are also derived and displayed. The display may then be interpreted by the user. The preferred embodiment includes a microprocessor which is interfaced with a television set for displaying of the sound formants. The microprocessor software enables the sound analyzer to present a variety of display modes for interpretive and therapeutic used by the user.

  17. Embedded and real-time operating systems

    Wang, K C


    This book covers the basic concepts and principles of operating systems, showing how to apply them to the design and implementation of complete operating systems for embedded and real-time systems. It includes all the foundational and background information on ARM architecture, ARM instructions and programming, toolchain for developing programs, virtual machines for software implementation and testing, program execution image, function call conventions, run-time stack usage and link C programs with assembly code. It describes the design and implementation of a complete OS for embedded systems in incremental steps, explaining the design principles and implementation techniques. For Symmetric Multiprocessing (SMP) embedded systems, the author examines the ARM MPcore processors, which include the SCU and GIC for interrupts routing and interprocessor communication and synchronization by Software Generated Interrupts (SGIs). Throughout the book, complete working sample systems demonstrate the design principles and...

  18. Operational and real-time Business Intelligence

    Daniela Ioana SANDU


    Full Text Available A key component of a company’s IT framework is a business intelligence (BI system. BI enables business users to report on, analyze and optimize business operations to reduce costs and increase revenues. Organizations use BI for strategic and tactical decision making where the decision-making cycle may span a time period of several weeks (e.g., campaign management or months (e.g., improving customer satisfaction.Competitive pressures coming from a very dynamic business environment are forcing companies to react faster to changing business conditions and customer requirements. As a result, there is now a need to use BI to help drive and optimize business operations on a daily basis, and, in some cases, even for intraday decision making. This type of BI is usually called operational business intelligence and real-time business intelligence.

  19. Real-Time Optical Antimicrobial Susceptibility Testing

    Fredborg, Marlene; Andersen, Klaus R; Jørgensen, Erik


    Rapid antibiotic susceptibility testing is in highly demand in health-care fields as antimicrobial resistant bacterial strains emerge and spread. Here we describe an optical screening system (oCelloScope), which based on time-lapse imaging of 96 bacteria-antibiotic combinations at a time, introdu......Rapid antibiotic susceptibility testing is in highly demand in health-care fields as antimicrobial resistant bacterial strains emerge and spread. Here we describe an optical screening system (oCelloScope), which based on time-lapse imaging of 96 bacteria-antibiotic combinations at a time......, introduces real-time detection of bacterial growth and antimicrobial susceptibility, with imaging material to support the automatically generated graphs. Automated antibiotic susceptibility tests of a monoculture showed statistically significant antibiotic effect within 6 minutes and within 30 minutes...

  20. Real-time forecasts of dengue epidemics

    Yamana, T. K.; Shaman, J. L.


    Dengue is a mosquito-borne viral disease prevalent in the tropics and subtropics, with an estimated 2.5 billion people at risk of transmission. In many areas with endemic dengue, disease transmission is seasonal but prone to high inter-annual variability with occasional severe epidemics. Predicting and preparing for periods of higher than average transmission is a significant public health challenge. Here we present a model of dengue transmission and a framework for optimizing model simulations with real-time observational data of dengue cases and environmental variables in order to generate ensemble-based forecasts of the timing and severity of disease outbreaks. The model-inference system is validated using synthetic data and dengue outbreak records. Retrospective forecasts are generated for a number of locations and the accuracy of these forecasts is quantified.

  1. Terrestrial Real-Time Volcano Monitoring

    Franke, M.


    As volcano monitoring involves more and different sensors from seismic to GPS receivers, from video and thermal cameras to multi-parameter probes measuring temperature, ph values and humidity in the ground and the air, it becomes important to design real-time networks that integrate and leverage the multitude of available parameters. In order to do so some simple principles need to be observed: a) a common time base for all measurements, b) a packetized general data communication protocol for acquisition and distribution, c) an open and well documented interface to the data permitting standard and emerging innovative processing, and d) an intuitive visualization platform for scientists and civil defense personnel. Although mentioned as simple principles, the list above does not necessarily lead to obvious solutions or integrated systems, which is, however, required to take advantage of the available data. Only once the different data streams are put into context to each other in terms of time and location can a broader view be obtained and additional information extracted. The presentation is a summary of currently available technologies and how they can achieve the goal of an integrated real-time volcano monitoring system. A common time base are standard for seismic and GPS networks. In different projects we extended this to video feeds and time-lapse photography. Other probes have been integrated with vault interface enclosures (VIE) as used in the Transportable Array (TA) of the USArray. The VIE can accommodate the sensors employed in volcano monitoring. The TA has shown that Antelope is a versatile and robust middleware. It provides the required packetized general communication protocol that is independent from the actual physical communication link leaving the network design to adopt appropriate and possible hybrid solutions. This applies for the data acquisition and the data/information dissemination providing both a much needed collaboration platform, as


    Marius Bogdan DINU


    Full Text Available The RTDW concept originated in the early 2000s. By that time, computing power had increased to a level that was allowing extraction of data collections for reporting purposes. Such collections were used almost in real time and at speeds nearly comparable to what an operation system was capable to deliver. The main idea will be to eliminate some of the components of the classic extraction process which is basically the most costly factor less time - consuming. We anticipate that the following factors will be decisive: elimination of batch-type processes [1], data compression techniques, data capture techniques, ability to keep in cache a large volume of data, parallel processing, and data mining algorithms that can adapt to such applications.

  3. A Flexible Real-Time Architecture



    Assuring hard real-time characteristics of I/O associated with embedded software is often a difficult task. Input-Output related statements are often intermixed with the computational code, resulting in I/O timing that is dependent on the execution path and computational load. One way to mitigate this problem is through the use of interrupts. However, the non-determinism that is introduced by interrupt driven I/O may be so difficult to analyze that it is prohibited in some high consequence systems. This paper describes a balanced hardware/software solution to obtain consistent interrupt-free I/O timing, and results in software that is much more amenable to analysis.

  4. Real-time color holographic interferometry

    Desse, Jean-Michel; Albe, Felix; Tribillon, Jean-Louis


    A new optical technique based on real-time color holographic interferometry has been developed for analyzing unsteady aerodynamic wakes in fluid mechanics or for measuring displacements and deformations in solid mechanics. The technique's feasibility is demonstrated here. It uses three coherent wavelengths produced simultaneously by a cw laser (mixed argon and krypton). Holograms are recorded on single-layer panchromatic silver halide (Slavich PFG 03C) plates. Results show the optical setup can be adjusted to obtain a uniform background color. The interference fringe pattern visualized is large and colored and exhibits a single central white fringe, which makes the zero order of the interferogram easy to identify. An application in a subsonic wind tunnel is presented, in which the unsteady wake past a cylinder is recorded at high rate.

  5. Wi-Fi real time location systems

    Doll, Benjamin A.

    This thesis objective was to determine the viability of utilizing an untrained Wi-Fi. real time location system as a GPS alternative for indoor environments. Background. research showed that GPS is rarely able to penetrate buildings to provide reliable. location data. The benefit of having location information in a facility and how they might. be used for disaster or emergency relief personnel and their resources motivated this. research. A building was selected with a well-deployed Wi-Fi infrastructure and its. untrained location feature was used to determine the distance between the specified. test points and the system identified location. It was found that the average distance. from the test point throughout the facility was 14.3 feet 80% of the time. This fell within. the defined viable range and supported that an untrained Wi-Fi RTLS system could be a. viable solution for GPS's lack of availability indoors.

  6. Real-Time Imaging of Quantum Entanglement

    Fickler, Robert; Lapkiewicz, Radek; Ramelow, Sven; Zeilinger, Anton


    Quantum Entanglement - correlations between at least two systems that are stronger than classically explainable - is widely regarded as one of the most prominent features of quantum mechanics and quantum information science. Although, the creation of entanglement between two systems has become possible in laboratories, it has been out of the grasp of one of the most natural ways to investigate nature: direct visual observation. Here we show that modern imaging technology, namely a triggered intensified charge coupled device (ICCD) camera, is fast and sensitive enough to image in real-time the influence of the measurement of one photon on its entangled partner. To demonstrate the non-classicality of the measurements quantitatively from the registered intensity we develop a novel method to statistically analyze the image and precisely quantify the number of photons within a certain region. In addition, we show the high flexibility of our experimental setup in creating any desired spatial-mode entanglement, even...

  7. Real-time visualization of joint cavitation.

    Gregory N Kawchuk

    Full Text Available Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1-weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic resonance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than collapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking.

  8. Real Time Eye Template Detection and Tracking

    Richa Mehta


    Full Text Available There has been a growing interest in the field of facial expression recognition especially in the last two decades. An example of such a system is the improvement of driver carefulness and accident reduction. The driver’s face is tracked while he is driving and he is warned if there seems to be an alerting fact that can result in an accident such as sleepy eyes, or looking out of the road. Furthermore, with a facial feature tracker, it becomes possible to play a synthesized avatar so that it imitates the expressions of the performer. Human-Computer Interaction (HCI systems may also be enriched by a facial feature tracker. For a user who is incapable of using her hands, a facial expression controller may be a solution to send limited commands to a computer. Eye blinking is one of the prominent areas to solve many real world problems. The process of blink detection consists of two phases. These are eye tracking followed by detection of blink. The work that has been carried out for eye tracking only is not suitable for eye blink detection. Therefore some approaches had been proposed for eye tracking along with eyes blink detection. In this thesis, real time implementation is done to count number of eye blinks in an image sequence. At last after analyzing all these approaches some of the parameters we obtained on which better performance of eye blink detection algorithm depend. This project focuses on automatic eye blink detection in real time. The aim of this thesis is to count the number of eye blinks in a video. This project will be performed on a video database of the facial expressions.

  9. Towards real time speckle controlled retinal photocoagulation

    Bliedtner, Katharina; Seifert, Eric; Stockmann, Leoni; Effe, Lisa; Brinkmann, Ralf


    Photocoagulation is a laser treatment widely used for the therapy of several retinal diseases. Intra- and inter-individual variations of the ocular transmission, light scattering and the retinal absorption makes it impossible to achieve a uniform effective exposure and hence a uniform damage throughout the therapy. A real-time monitoring and control of the induced damage is highly requested. Here, an approach to realize a real time optical feedback using dynamic speckle analysis is presented. A 532 nm continuous wave Nd:YAG laser is used for coagulation. During coagulation, speckle dynamics are monitored by a coherent object illumination using a 633nm HeNe laser and analyzed by a CMOS camera with a frame rate up to 1 kHz. It is obvious that a control system needs to determine whether the desired damage is achieved to shut down the system in a fraction of the exposure time. Here we use a fast and simple adaption of the generalized difference algorithm to analyze the speckle movements. This algorithm runs on a FPGA and is able to calculate a feedback value which is correlated to the thermal and coagulation induced tissue motion and thus the achieved damage. For different spot sizes (50-200 μm) and different exposure times (50-500 ms) the algorithm shows the ability to discriminate between different categories of retinal pigment epithelial damage ex-vivo in enucleated porcine eyes. Furthermore in-vivo experiments in rabbits show the ability of the system to determine tissue changes in living tissue during coagulation.

  10. Incremental value of contrast myocardial perfusion to detect intermediate versus severe coronary artery stenosis during stress-echocardiography

    Ugo Fabrizio


    Full Text Available Abstract Background We aimed to compare the incremental value of contrast myocardial perfusion imaging (MPI for the detection of intermediate versus severe coronary artery stenosis during dipyridamole-atropine echocardiography (DASE. Wall motion (WM assessment during stress-echocardiography demonstrates suboptimal sensitivity to detect coronary artery disease (CAD, particularly in patients with isolated intermediate (50%-70% coronary stenosis. Methods We performed DASE with MPI in 150 patients with a suspected chest pain syndrome who were given clinical indication to coronary angiography. Results and discussion When CAD was defined as the presence of a ≥50% stenosis, the addition of MPI increased sensitivity (+30% and decreased specificity (-14%, with a final increase in total diagnostic accuracy (+16%, p Conclusions The addition of MPI on top of WM analysis during DASE increases the diagnostic sensitivity to detect obstructive CAD, whatever its definition (≥50% or > 70% stenosis, but it is mainly driven by the sensitivity increase in the intermediate group (50%-70% stenosis. The total diagnostic accuracy increased only when defining CAD as ≥50% stenosis, since in patients with severe stenosis (> 70% the decrease in specificity is not counterbalanced by the minor sensitivity increase.

  11. An Efficient Secure Real-Time Concurrency Control Protocol

    XIAO Yingyuan; LIU Yunsheng; CHEN Xiangyang


    Secure real-time databases must simultaneously satisfy two requirements in guaranteeing data security and minimizing the missing deadlines ratio of transactions. However, these two requirements can conflict with each other and achieve one requirement is to sacrifice the other. This paper presents a secure real-time concurrency control protocol based on optimistic method. The concurrency control protocol incorporates security constraints in a real-time optimistic concurrency control protocol and makes a suitable tradeoff between security and real-time requirements by introducing secure influence factor and real-time influence factor. The experimental results show the concurrency control protocol achieves data security without degrading real-time performance significantly.

  12. Real Time Seismic Prediction while Drilling

    Schilling, F. R.; Bohlen, T.; Edelmann, T.; Kassel, A.; Heim, A.; Gehring, M.; Lüth, S.; Giese, R.; Jaksch, K.; Rechlin, A.; Kopf, M.; Stahlmann, J.; Gattermann, J.; Bruns, B.


    Efficient and safe drilling is a prerequisite to enhance the mobility of people and goods, to improve the traffic as well as utility infrastructure of growing megacities, and to ensure the growing energy demand while building geothermal and in hydroelectric power plants. Construction within the underground is often building within the unknown. An enhanced risk potential for people and the underground building may arise if drilling enters fracture zones, karsts, brittle rocks, mixed solid and soft rocks, caves, or anthropogenic obstacles. Knowing about the material behavior ahead of the drilling allows reducing the risk during drilling and construction operation. In drilling operations direct observations from boreholes can be complemented with geophysical investigations. In this presentation we focus on “real time” seismic prediction while drilling which is seen as a prerequisite while using geophysical methods in modern drilling operations. In solid rocks P- and S-wave velocity, refraction and reflection as well as seismic wave attenuation can be used for the interpretation of structures ahead of the drilling. An Integrated Seismic Imaging System (ISIS) for exploration ahead of a construction is used, where a pneumatic hammer or a magnetostrictive vibration source generate repetitive signals behind the tunneling machine. Tube waves are generated which travel along the tunnel to the working face. There the tube waves are converted to mainly S- but also P-Waves which interact with the formation ahead of the heading face. The reflected or refracted waves travel back to the working front are converted back to tube waves and recorded using three-component geophones which are fit into the tips of anchor rods. In near real time, the ISIS software allows for an integrated 3D imaging and interpretation of the observed data, geological and geotechnical parameters. Fracture zones, heterogeneities, and variations in the rock properties can be revealed during the drilling

  13. The INGV Real Time Strong Motion Database

    Massa, Marco; D'Alema, Ezio; Mascandola, Claudia; Lovati, Sara; Scafidi, Davide; Gomez, Antonio; Carannante, Simona; Franceschina, Gianlorenzo; Mirenna, Santi; Augliera, Paolo


    The INGV real time strong motion data sharing is assured by the INGV Strong Motion Database. ISMD ( was designed in the last months of 2011 in cooperation among different INGV departments, with the aim to organize the distribution of the INGV strong-motion data using standard procedures for data acquisition and processing. The first version of the web portal was published soon after the occurrence of the 2012 Emilia (Northern Italy), Mw 6.1, seismic sequence. At that time ISMD was the first European real time web portal devoted to the engineering seismology community. After four years of successfully operation, the thousands of accelerometric waveforms collected in the archive need necessary a technological improvement of the system in order to better organize the new data archiving and to make more efficient the answer to the user requests. ISMD 2.0 was based on PostgreSQL (, an open source object- relational database. The main purpose of the web portal is to distribute few minutes after the origin time the accelerometric waveforms and related metadata of the Italian earthquakes with ML≥3.0. Data are provided both in raw SAC (counts) and automatically corrected ASCII (gal) formats. The web portal also provide, for each event, a detailed description of the ground motion parameters (i.e. Peak Ground Acceleration, Velocity and Displacement, Arias and Housner Intensities) data converted in velocity and displacement, response spectra up to 10.0 s and general maps concerning the recent and the historical seismicity of the area together with information about its seismic hazard. The focal parameters of the events are provided by the INGV National Earthquake Center (CNT, Moreover, the database provides a detailed site characterization section for each strong motion station, based on geological, geomorphological and geophysical information. At present (i.e. January 2017), ISMD includes 987 (121


    Mccluney, K.


    In a real-time environment, the results of changes or failures in a complex, interconnected system need evaluation quickly. Tabulations showing the effects of changes and/or failures of a given item in the system are generally only useful for a single input, and only with regard to that item. Subsequent changes become harder to evaluate as combinations of failures produce a cascade effect. When confronted by multiple indicated failures in the system, it becomes necessary to determine a single cause. In this case, failure tables are not very helpful. CRANS, the Configurable Real-time ANalysis System, can interpret a logic tree, constructed by the user, describing a complex system and determine the effects of changes and failures in it. Items in the tree are related to each other by Boolean operators. The user is then able to change the state of these items (ON/OFF FAILED/UNFAILED). The program then evaluates the logic tree based on these changes and determines any resultant changes to other items in the tree. CRANS can also search for a common cause for multiple item failures, and allow the user to explore the logic tree from within the program. A "help" mode and a reference check provide the user with a means of exploring an item's underlying logic from within the program. A commonality check determines single point failures for an item or group of items. Output is in the form of a user-defined matrix or matrices of colored boxes, each box representing an item or set of items from the logic tree. Input is via mouse selection of the matrix boxes, using the mouse buttons to toggle the state of the item. CRANS is written in C-language and requires the MIT X Window System, Version 11 Revision 4 or Revision 5. It requires 78K of RAM for execution and a three button mouse. It has been successfully implemented on Sun4 workstations running SunOS, HP9000 workstations running HP-UX, and DECstations running ULTRIX. No executable is provided on the distribution medium; however

  15. RTMOD: Real-Time MODel evaluation

    Graziani, G; Galmarini, S. [Joint Research centre, Ispra (Italy); Mikkelsen, T. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept. (Denmark)


    The 1998 - 1999 RTMOD project is a system based on an automated statistical evaluation for the inter-comparison of real-time forecasts produced by long-range atmospheric dispersion models for national nuclear emergency predictions of cross-boundary consequences. The background of RTMOD was the 1994 ETEX project that involved about 50 models run in several Institutes around the world to simulate two real tracer releases involving a large part of the European territory. In the preliminary phase of ETEX, three dry runs (i.e. simulations in real-time of fictitious releases) were carried out. At that time, the World Wide Web was not available to all the exercise participants, and plume predictions were therefore submitted to JRC-Ispra by fax and regular mail for subsequent processing. The rapid development of the World Wide Web in the second half of the nineties, together with the experience gained during the ETEX exercises suggested the development of this project. RTMOD featured a web-based user-friendly interface for data submission and an interactive program module for displaying, intercomparison and analysis of the forecasts. RTMOD has focussed on model intercomparison of concentration predictions at the nodes of a regular grid with 0.5 degrees of resolution both in latitude and in longitude, the domain grid extending from 5W to 40E and 40N to 65N. Hypothetical releases were notified around the world to the 28 model forecasters via the web on a one-day warning in advance. They then accessed the RTMOD web page for detailed information on the actual release, and as soon as possible they then uploaded their predictions to the RTMOD server and could soon after start their inter-comparison analysis with other modelers. When additional forecast data arrived, already existing statistical results would be recalculated to include the influence by all available predictions. The new web-based RTMOD concept has proven useful as a practical decision-making tool for realtime

  16. Prevalence of first-pass myocardial perfusion defects detected by contrast-enhanced dual-source CT in patients with non-ST segment elevation acute coronary syndromes

    Schepis, Tiziano; Achenbach, Stephan; Marwan, Mohamed; Muschiol, Gerd; Ropers, Dieter; Daniel, Werner G.; Pflederer, Tobias [University of Erlangen, Department of Internal Medicine 2 (Cardiology), Erlangen (Germany)


    To investigate the prevalence and diagnostic value of first-pass myocardial perfusion defects (PD) visualised by contrast-enhanced multidetector computed tomography (MDCT) in patients admitted for a first acute coronary syndrome (ACS). Thirty-eight patients with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and scheduled for percutaneous coronary intervention underwent dual-source CT immediately before catheterisation. CT images were analysed for the presence of any PD by using a 17-segment model. Results were compared with peak cardiac troponin-I (cTnI) and angiography findings. PD were seen in 21 of the 24 patients with NSTEMI (median peak cTnI level 7.07 ng/mL; range 0.72-37.07 ng/mL) and in 2 of 14 patients with UA. PD corresponded with the territory of the infarct-related artery in 20 out of 22 patients. In a patient-based analysis, sensitivity, specificity, negative and positive predictive values of any PD for predicting NSTEMI were 88%, 86%, 80% and 91%. Per culprit artery, the respective values were 86%, 75%, 80% and 83%. In patients with non-ST segment elevation ACS, first-pass myocardial PD in contrast-enhanced MDCT correlate closely with the presence of myocardial necrosis, as determined by increases in cTnI levels. (orig.)

  17. Computational Fluid Dynamics Simulations of Contrast Agent Bolus Dispersion in a Coronary Bifurcation: Impact on MRI-Based Quantification of Myocardial Perfusion

    Regine Schmidt


    Full Text Available Contrast-enhanced first-pass magnetic resonance imaging (MRI in combination with a tracer kinetic model, for example, MMID4, can be used to determine myocardial blood flow (MBF and myocardial perfusion reserve (MPR. Typically, the arterial input function (AIF required for this methodology is estimated from the left ventricle (LV. Dispersion of the contrast agent bolus might occur between the LV and the myocardial tissue. Negligence of bolus dispersion could cause an error in MBF determination. The aim of this study was to investigate the influence of bolus dispersion in a simplified coronary bifurcation geometry including one healthy and one stenotic branch on the quantification of MBF and MPR. Computational fluid dynamics (CFD simulations were combined with MMID4. Different inlet boundary conditions describing pulsatile and constant flows for rest and hyperemia and differing outflow conditions have been investigated. In the bifurcation region, the increase of the dispersion was smaller than inside the straight vessels. A systematic underestimation of MBF values up to −16.1% for pulsatile flow and an overestimation of MPR up to 7.5% were found. It was shown that, under the conditions considered in this study, bolus dispersion can significantly influence the results of quantitative myocardial MR-perfusion measurements.

  18. Real-time luminescence imaging of cellular ATP release.

    Furuya, Kishio; Sokabe, Masahiro; Grygorczyk, Ryszard


    Extracellular ATP and other purines are ubiquitous mediators of local intercellular signaling within the body. While the last two decades have witnessed enormous progress in uncovering and characterizing purinergic receptors and extracellular enzymes controlling purinergic signals, our understanding of the initiating step in this cascade, i.e., ATP release, is still obscure. Imaging of extracellular ATP by luciferin-luciferase bioluminescence offers the advantage of studying ATP release and distribution dynamics in real time. However, low-light signal generated by bioluminescence reactions remains the major obstacle to imaging such rapid processes, imposing substantial constraints on its spatial and temporal resolution. We have developed an improved microscopy system for real-time ATP imaging, which detects ATP-dependent luciferin-luciferase luminescence at ∼10 frames/s, sufficient to follow rapid ATP release with sensitivity of ∼10 nM and dynamic range up to 100 μM. In addition, simultaneous differential interference contrast cell images are acquired with infra-red optics. Our imaging method: (1) identifies ATP-releasing cells or sites, (2) determines absolute ATP concentration and its spreading manner at release sites, and (3) permits analysis of ATP release kinetics from single cells. We provide instrumental details of our approach and give several examples of ATP-release imaging at cellular and tissue levels, to illustrate its potential utility.

  19. Asbestos real-time monitor in an atmospheric environment.

    Hiromoto, N; Hashiguchi, K; Ito, S; Itabe, T


    The concentration of asbestos fiber aerosols can be monitored by measuring the polarization of laser light scattered by asbestos fibers. The principle of discriminating asbestos fibers is based on the theoretically expected difference in polarization at a scattering angle of 170 deg between cylindrical and spherical airborne particles; polarization at this scattering angle should be positive for cylindrical particles such as asbestos fibers but should be negative or close to zero for spherical mineral particles. We constructed an experimental asbestos real-time monitor that uses a strong electric field to align the airborne particles, that uses lasers having linear polarization with an equal amplitude in parallel and perpendicular components to the aligned long axis of particles, and that simultaneously detects the two components of the linear polarization of light scattered at 170 deg, i.e., close to the backscatter. Experiments that were performed to detect the light scattered from airborne standard asbestos fibers showed that the measured polarization fits theoretical prediction. The concentrations of airborne asbestos fibers obtained by the asbestos real-time monitor were consistent with those estimated by the standard phase contrast microscope method.

  20. Application of real-time GPS to earthquake early warning

    Richard M. Allen; Alon Ziv


      Real-time GPS can provide static-offset observations during an earthquake Real-time GPS provides a robust constrain on magnitude for warnings GPS networks should be used as a companion to seismic...

  1. The Colliderscope: a real-time show

    Francesco Poppi


    Ninety-six LED lights distributed over the facade of the Niels Bohr Institute (NBI) in Blegdamsvej (Denmark) reproduce the actual signals coming from the Transition Radiation Detector (TRT) in ATLAS. Thanks to the Colliderscope, when a collision occurs below the ground in Geneva, people passing by in Blegdamsvej will be aware of it almost in real-time.   Niels Bohr Institute facade lit up to reflect the latest data from ATLAS-TRT . The pattern, intensity and duration of the Colliderscope’s flashes of light depend on the physical parameters of particles crossing the ATLAS TRT detector. “At the Colliderscope very little happens randomly”, explains Troels Petersen, a physicist at NBI and one of the people who conceived it. “Particularly interesting events, such as electrons, are shown by a bright light that remains on the facade for several seconds”. The Niels Bohr Institute has participated in the development of the TRT detector, and this is why t...

  2. Business Hypervisors for Real-time Applications

    L. Perneel


    Full Text Available System virtualization is one of the hottest trends in information technology today. It is not just another nice to use technology but has become fundamental across the business world. It is successfully used with many business application classes where cloud computing is the most visual one. Recently, it started to be used for soft Real-Time (RT applications such as IP telephony, media servers, audio and video streaming servers, automotive and communication systems in general. Running these applications on a traditional system (Hardware + Operating System guarantee their Quality of Service (QoS; virtualizing them means inserting a new layer between the hardware and the (virtual Operating System (OS, and thus adding extra overhead. Although these applications’ areas do not always demand hard time guarantees, they require the underlying virtualization layer supports low latency and provide adequate computational resources for completion within a reasonable or predictable timeframe. These aspects are intimately intertwined with the logic of the hypervisor scheduler. In this paper, a series of tests are conducted on three hypervisors (VMware ESXi, Hyper-V server and Xen to provide a benchmark of the latencies added to the applications running on top of them. These tests are conducted for different scenarios (use cases to take into consideration all the parameters and configurations of the hypervisors’ schedulers. Finally, this benchmark can be used as a reference for choosing the best hypervisor-application combination.

  3. Real-time flexible preventive maintenance scheduling.

    Kendall, E B; Cronk, J W; White, R N


    There are still obstacles to overcome as we enter the programming phase of this project. We envision an automated system, similar to an expert system, that performs the interval/history analysis and makes the changes. Initially a field will need to be added to the inventory to denote whether a device belongs to one of the previously described groups that are exempt from interval changes. An intermediate step will be the formatting of a periodic report showing equipment that meets the change criteria as described in the two rules. For now, the actual changes would be reviewed and made by our management and technical staff. This report would be retained as documentation of the basis for each change, for our own benefit and to meet JCAHO requirements. We are still discussing whether the repair count should include all repairs (user error, abuse, unpredictable failure, etc.) or just those that are "significant and preventable" and could have been averted by PM. This is perhaps a question whose answer might vary from hospital to hospital, depending upon size and patient mix. With more emphasis being placed on process outcomes, on quality of work, and on getting the most benefit for our efforts, we believe our flexible, real-time PM scheduling program is a major step in the right direction. It is outcome-driven and it focuses resources where they are needed the most.

  4. Real time model for public transportation management

    Ireneusz Celiński


    Full Text Available Background: The article outlines managing a public transportation fleet in the dynamic aspect. There are currently many technical possibilities of identifying demand in the transportation network. It is also possible to indicate legitimate basis of estimating and steering demand. The article describes a general public transportation fleet management concept based on balancing demand and supply. Material and methods: The presented method utilizes a matrix description of demand for transportation based on telemetric and telecommunication data. Emphasis was placed mainly on a general concept and not the manner in which data was collected by other researchers.  Results: The above model gave results in the form of a system for managing a fleet in real-time. The objective of the system is also to optimally utilize means of transportation at the disposal of service providers. Conclusions: The presented concept enables a new perspective on managing public transportation fleets. In case of implementation, the project would facilitate, among others, designing dynamic timetables, updated based on observed demand, and even designing dynamic points of access to public transportation lines. Further research should encompass so-called rerouting based on dynamic measurements of the characteristics of the transportation system.

  5. Recommendations for Real-Time Speech MRI

    Lingala, Sajan Goud; Sutton, Brad P.; Miquel, Marc E.; Nayak, Krishna S.


    Real-time magnetic resonance imaging (RT-MRI) is being increasingly used for speech and vocal production research studies. Several imaging protocols have emerged based on advances in RT-MRI acquisition, reconstruction, and audio-processing methods. This review summarizes the state-of-the-art, discusses technical considerations, and provides specific guidance for new groups entering this field. We provide recommendations for performing RT-MRI of the upper airway. This is a consensus statement stemming from the ISMRM-endorsed Speech MRI summit held in Los Angeles, February 2014. A major unmet need identified at the summit was the need for consensus on protocols that can be easily adapted by researchers equipped with conventional MRI systems. To this end, we provide a discussion of tradeoffs in RT-MRI in terms of acquisition requirements, a priori assumptions, artifacts, computational load, and performance for different speech tasks. We provide four recommended protocols and identify appropriate acquisition and reconstruction tools. We list pointers to open-source software that facilitate implementation. We conclude by discussing current open challenges in the methodological aspects of RT-MRI of speech. PMID:26174802

  6. Real-time optoacoustic monitoring of stroke

    Kneipp, Moritz; Turner, Jake; Hambauer, Sebastian; Krieg, Sandro M.; Lehmberg, Jens; Lindauer, Ute; Razansky, Daniel


    Characterizing disease progression and identifying possible therapeutic interventions in stroke is greatly aided by the use of longitudinal function imaging studies. In this study, we investigate the applicability of real-time multispectral optoacoustic tomography (MSOT) as a tool for non-invasive monitoring of the progression of stroke in the whole brain. The middle cerebral artery occlusion (MCAO) method was used to induce stroke. Mice were imaged under isoflurane anesthesia preoperatively and at several time points during and after the 60-minute occlusion. The animals were sacrificed after 24 hours and their excised brains frozen at -80°C for sectioning. The cryosection were stained using H&E staining to identify the ischemic lesion. Major vessels are readily identifiable in the whole mouse head in the in vivo optoacoustic scans. During ischemia, a reduction in cerebral blood volume is detectable in the cortex. Post ischemia, spectral unmixing of the optoacoustic signals shows an asymmetry of the deoxygenated hemoglobin in the hemisphere affected by MCAO. This hypoxic area was mainly located around the boundary of the ischemic lesion and was therefore identified as the ischemic penumbra. Non-invasive functional MSOT imaging is able to visualize the hypoxic penumbra in brains affected by stroke. Stopping the spread of the infarct area and revitalizing the penumbra is central in stroke research, this new imaging technique may therefore prove to be a valuable tool in the monitoring and developing new treatments.

  7. Real-time Detection of Locked Modes

    Angelini, S.; Granetz, R. S.; Wolfe, S. M.


    Disruptions are one of the largest problems facing tokamaks. In a large-scale experiment such as ITER, disruptions would cause crippling damage and severe setbacks in experimentation. One method for disruption mitigation involves the use of a gas jet which has been tested on both normally running plasmas and vertical displacement events (VDEs) on Alcator C-Mod. In both cases, the jet was successful in mitigating disruption effects. The gas jet has not yet been tested on other types of disruptions. Locked-mode major disruptions are easily created in C-Mod and could be used to test the effectiveness of the gas jet as a mitigation method if the jet could be fired early enough. It has been empirically observed that the electron cyclotron emissions (ECE) signal displays a flattening of the normally-present sawteeth before the current quench occurs in certain locked-mode major disruptions. A procedure is being written which will detect the ECE flattening by reading changes in the standard deviation of the signal. This procedure will be programmed into the digital plasma control system (DPCS) for real-time testing.

  8. Real-time DIRCM system modeling

    Petersson, Mikael


    Directed infrared countermeasures (DIRCM) play an increasingly important role in electronic warfare to counteract threats posed by infrared seekers. The usefulness and performance of such countermeasures depend, for example, on atmospheric conditions (attenuation and turbulence) and platform vibrations, causing pointing and tracking errors for the laser beam and reducing the power transferred to the seeker aperture. These problems make it interesting to simulate the performance of a DIRCM system in order to understand how easy or difficult it is to counteract an approaching threat and evaluate limiting factors in various situations. This paper describes a DIRCM model that has been developed, including atmospheric effects such as attenuation and turbulence as well as closed loop tracking algorithms, where the retro reflex of the laser is used for the pointing control of the beam. The DIRCM model is part of a large simulation framework (EWSim), which also incorporates several descriptions of different seekers (e.g. reticle, rosette, centroid, nutating cross) and models of robot dynamics. Effects of a jamming laser on a specific threat can be readily verified by simulations within this framework. The duel between missile and countermeasure is simulated in near real-time and visualized graphically in 3D. A typical simulation with a reticle seeker jammed by a modulated laser is included in the paper.

  9. Real-Time Principal-Component Analysis

    Duong, Vu; Duong, Tuan


    A recently written computer program implements dominant-element-based gradient descent and dynamic initial learning rate (DOGEDYN), which was described in Method of Real-Time Principal-Component Analysis (NPO-40034) NASA Tech Briefs, Vol. 29, No. 1 (January 2005), page 59. To recapitulate: DOGEDYN is a method of sequential principal-component analysis (PCA) suitable for such applications as data compression and extraction of features from sets of data. In DOGEDYN, input data are represented as a sequence of vectors acquired at sampling times. The learning algorithm in DOGEDYN involves sequential extraction of principal vectors by means of a gradient descent in which only the dominant element is used at each iteration. Each iteration includes updating of elements of a weight matrix by amounts proportional to a dynamic initial learning rate chosen to increase the rate of convergence by compensating for the energy lost through the previous extraction of principal components. In comparison with a prior method of gradient-descent-based sequential PCA, DOGEDYN involves less computation and offers a greater rate of learning convergence. The sequential DOGEDYN computations require less memory than would parallel computations for the same purpose. The DOGEDYN software can be executed on a personal computer.

  10. Real-Time Accumulative Computation Motion Detectors

    Saturnino Maldonado-Bascón


    Full Text Available The neurally inspired accumulative computation (AC method and its application to motion detection have been introduced in the past years. This paper revisits the fact that many researchers have explored the relationship between neural networks and finite state machines. Indeed, finite state machines constitute the best characterized computational model, whereas artificial neural networks have become a very successful tool for modeling and problem solving. The article shows how to reach real-time performance after using a model described as a finite state machine. This paper introduces two steps towards that direction: (a A simplification of the general AC method is performed by formally transforming it into a finite state machine. (b A hardware implementation in FPGA of such a designed AC module, as well as an 8-AC motion detector, providing promising performance results. We also offer two case studies of the use of AC motion detectors in surveillance applications, namely infrared-based people segmentation and color-based people tracking, respectively.

  11. Real-Time 3D Visualization


    Butler Hine, former director of the Intelligent Mechanism Group (IMG) at Ames Research Center, and five others partnered to start Fourth Planet, Inc., a visualization company that specializes in the intuitive visual representation of dynamic, real-time data over the Internet and Intranet. Over a five-year period, the then NASA researchers performed ten robotic field missions in harsh climes to mimic the end- to-end operations of automated vehicles trekking across another world under control from Earth. The core software technology for these missions was the Virtual Environment Vehicle Interface (VEVI). Fourth Planet has released VEVI4, the fourth generation of the VEVI software, and NetVision. VEVI4 is a cutting-edge computer graphics simulation and remote control applications tool. The NetVision package allows large companies to view and analyze in virtual 3D space such things as the health or performance of their computer network or locate a trouble spot on an electric power grid. Other products are forthcoming. Fourth Planet is currently part of the NASA/Ames Technology Commercialization Center, a business incubator for start-up companies.

  12. Execution of a High Level Real-Time Language

    Luqi; Berzins, Valdis


    Prototype System Description Language (PSDL) is a high level real-time language with special features for hard real-time system specification and design. It can be used to firm up requirements through execution of its software prototypes The language is designed based on a real-time model merging data and control flow and its implementation is beyond conventional compiler technology because of the need to meet real-time constraints. In this paper we describe and illustrate our research result...

  13. A Real-Time Linux for Multicore Platforms


    Multicore Platforms, 25th Euromicro Conference on Real-TimeSystems. 09-JUL-13, . : , Jeremy Erickson, James Anderson. Reducing Tardiness Under Global...Baruah. "Improved tardiness bounds for Global EDF," Proceedings of the EuroMicro Conference on Real-Time Systems, Brussels, Belgium, IEEE Computer...missed. In a soft real-time application, some deadline tardiness is permissible. In the definition of "soft real-time" that we have focused on

  14. Survey of real-time processing systems for big data

    Liu, Xiufeng; Lftikhar, Nadeem; Xie, Xike


    for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  15. Myocardial contrast defect associated with thrombotic coronary occlusion: Pre-autopsy diagnosis of a cardiac death with post-mortem CT angiography

    Lee, Heon; Cha, Jang Gyu [Dept. of Radiology, Soonchunhyang University Hospital, Bucheon (Korea, Republic of); Park, Hye Jin; Lee, Soo Kyoung; Yang, Kyung Moo [Dept. of Forensic Medicine, National Forensic Service, Wonju (Korea, Republic of)


    We report the case of a female who died of suspected acute myocardial infarction. Post-mortem CT angiography (PMCTA) was performed with intravascular contrast infusion before the standard autopsy, and it successfully demonstrated the complete thrombotic occlusion of a coronary artery and also a corresponding perfusion defect on myocardium. We herein describe the PMCTA findings of a cardiac death with special emphasis on the potential benefits of this novel CT technique in forensic practice.

  16. Real time PV manufacturing diagnostic system

    Kochergin, Vladimir [MicroXact Inc., Blacksburg, VA (United States); Crawford, Michael A. [MicroXact Inc., Blacksburg, VA (United States)


    The main obstacle Photovoltaic (PV) industry is facing at present is the higher cost of PV energy compared to that of fossil energy. While solar cell efficiencies continue to make incremental gains these improvements are so far insufficient to drive PV costs down to match that of fossil energy. Improved in-line diagnostics however, has the potential to significantly increase the productivity and reduce cost by improving the yield of the process. On this Phase I/Phase II SBIR project MicroXact developed and demonstrated at CIGS pilot manufacturing line a high-throughput in-line PV manufacturing diagnostic system, which was verified to provide fast and accurate data on the spatial uniformity of thickness, an composition of the thin films comprising the solar cell as the solar cell is processed reel-to-reel. In Phase II project MicroXact developed a stand-alone system prototype and demonstrated the following technical characteristics: 1) ability of real time defect/composition inconsistency detection over 60cm wide web at web speeds up to 3m/minute; 2) Better than 1mm spatial resolution on 60cm wide web; 3) an average better than 20nm spectral resolution resulting in more than sufficient sensitivity to composition imperfections (copper-rich and copper-poor regions were detected). The system was verified to be high vacuum compatible. Phase II results completely validated both technical and economic feasibility of the proposed concept. MicroXact’s solution is an enabling technique for in-line PV manufacturing diagnostics to increase the productivity of PV manufacturing lines and reduce the cost of solar energy, thus reducing the US dependency on foreign oil while simultaneously reducing emission of greenhouse gasses.

  17. Real-Time Gender Classification by Face

    Eman Fares Al Mashagba


    Full Text Available The identification of human beings based on their biometric body parts, such as face, fingerprint, gait, iris, and voice, plays an important role in electronic applications and has become a popular area of research in image processing. It is also one of the most successful applications of computer–human interaction and understanding. Out of all the abovementioned body parts,the face is one of most popular traits because of its unique features.In fact, individuals can process a face in a variety of ways to classify it by its identity, along with a number of other characteristics, such as gender, ethnicity, and age. Specifically, recognizing human gender is important because people respond differently according to gender. In this paper, we present a robust method that uses global geometry-based features to classify gender and identify age and human beings from video sequences. The features are extracted based on face detection using skin color segmentation and the computed geometric features of the face ellipse region. These geometric features are then used to form the face vector trajectories, which are inputted to a time delay neural network and are trained using the Broyden–Fletcher–Goldfarb–Shanno (BFGS function. Results show that using the suggested method with our own dataset under an unconstrained condition achieves a 100% classification rate in the training set for all application, as well as 91.2% for gender classification, 88% for age identification, and 83% for human identification in the testing set. In addition, the proposed method establishes the real-time system to be used in three applications with a simple computation for feature extraction.

  18. Adaptive real-time signal processing for image enhancement

    Sadjadi, Firooz A.; Au, Wing K.


    A significant need exists for autonomous landing of an aircraft in adverse weather conditions, e.g., fog, haze, rain or snow. Such systems must provide the pilot the ability to view the runway and its surrounding with timely display information for each weather landing category. The most important requirements of such vision systems include a large field-of-view, a high update/frame rate, and high spatial resolution at low glazing angle in poor visibility conditions. To satisfy these requirements, Honeywell's System and Research Center has developed and demonstrated through flight tests the feasibility of a synthetic vision system for aircraft landing. This paper introduces the concept of the synthetic vision system, based on the Honeywell 35 GHz millimeter wave radar. It provides a detailed discussion on the adaptive image enhancement algorithms and their real-time implementation. The algorithms include beam sharpening and range adaptive contrast enhancement.

  19. Near Real-Time Browsable Landsat-8 Imagery

    Cheng-Chien Liu


    Full Text Available The successful launch and operation of Landsat-8 extends the remarkable 40-year acquisition of space-based land remote-sensing data. To respond quickly to emergency needs, real-time data are directly downlinked to 17 ground stations across the world on a routine basis. With a size of approximately 1 Gb per scene, however, the standard level-1 product provided by these stations is not able to serve the general public. Users would like to browse the most up-to-date and historical images of their regions of interest (ROI at full-resolution from all kinds of devices without the need for tedious data downloading, decompressing, and processing. This paper reports on the Landsat-8 automatic image processing system (L-8 AIPS that incorporates the function of mask developed by United States Geological Survey (USGS, the pan-sharpening technique of spectral summation intensity modulation, the adaptive contrast enhancement technique, as well as the Openlayers and Google Maps/Earth compatible superoverlay technique. Operation of L-8 AIPS enables the most up-to-date Landsat-8 images of Taiwan to be browsed with a clear contrast enhancement regardless of the cloud condition, and in only one hour’s time after receiving the raw data from the USGS Level 1 Product Generation System (LPGS. For any ROI in Taiwan, all historical Landsat-8 images can also be quickly viewed in time series at full resolution (15 m. The debris flow triggered by Typhoon Soudelor (8 August 2015, as well as the barrier lake formed and the large-scale destruction of vegetation after Typhoon Nepartak (7 July 2016, are given as three examples of successful applications to demonstrate that the gap between the user’s needs and the existing Level-1 product from LPGS can be bridged by providing browsable images in near real-time.

  20. ControlShell - A real-time software framework

    Schneider, Stanley A.; Ullman, Marc A.; Chen, Vincent W.


    ControlShell is designed to enable modular design and impplementation of real-time software. It is an object-oriented tool-set for real-time software system programming. It provides a series of execution and data interchange mechansims that form a framework for building real-time applications. These mechanisms allow a component-based approach to real-time software generation and mangement. By defining a set of interface specifications for intermodule interaction, ControlShell provides a common platform that is the basis for real-time code development and exchange.

  1. Satellite clock corrections estimation to accomplish real time ppp: experiments for brazilian real time network

    Marques, Haroldo; Monico, João; Aquino, Marcio; Melo, Weyller


    The real time PPP method requires the availability of real time precise orbits and satellites clocks corrections. Currently, it is possible to apply the solutions of clocks and orbits available by BKG within the context of IGS Pilot project or by using the operational predicted IGU ephemeris. The accuracy of the satellite position available in the IGU is enough for several applications requiring good quality. However, the satellites clocks corrections do not provide enough accuracy (3 ns ~ 0.9 m) to accomplish real time PPP with the same level of accuracy. Therefore, for real time PPP application it is necessary to further research and develop appropriated methodologies for estimating the satellite clock corrections in real time with better accuracy. Currently, it is possible to apply the real time solutions of clocks and orbits available by Federal Agency for Cartography and Geodesy (BKG) within the context of IGS Pilot project. The BKG corrections are disseminated by a new proposed format of the RTCM 3.x and can be applied in the broadcasted orbits and clocks. Some investigations have been proposed for the estimation of the satellite clock corrections using GNSS code and phase observable at the double difference level between satellites and epochs (MERVAT, DOUSA, 2007). Another possibility consists of applying a Kalman Filter in the PPP network mode (HAUSCHILD, 2010) and it is also possible the integration of both methods, using network PPP and observables at double difference level in specific time intervals (ZHANG; LI; GUO, 2010). For this work the methodology adopted consists in the estimation of the satellite clock corrections based on the data adjustment in the PPP mode, but for a network of GNSS stations. The clock solution can be solved by using two types of observables: code smoothed by carrier phase or undifferenced code together with carrier phase. In the former, we estimate receiver clock error; satellite clock correction and troposphere, considering

  2. Real Time Wide Area Radiation Surveillance System

    Biafore, M.


    We present the REWARD project, financed within the FP7 programme, theme SEC-2011.1.5-1 (Development of detection capabilities of difficult to detect radioactive sources and nuclear materials - Capability Project). Within this project, we propose a novel mobile system for real time, wide area radiation surveillance. The system is based on the integration of new miniaturized solid-state radiation sensors: a CdZnTe detector for gamma radiation and a high efficiency neutron detector based on novel silicon technologies. The sensing unit will include a wireless communication interface to send the data remotely to a monitoring base station which also uses a GPS system to calculate the position of the tag. The system will also incorporate middleware and high level software to provide web-service interfaces for the exchange of information, and that will offer top level functionalities as management of users, mobile tags and environment data and alarms, database storage and management and a web-based graphical user interface. Effort will be spent to ensure that the software is modular and re-usable across as many architectural levels as possible. Finally, an expert system will continuously analyze the information from the radiation sensor and correlate it with historical data from the tag location in order to generate an alarm when an abnormal situation is detected. The system will be useful for many different scenarios, including such lost radioactive sources and radioactive contamination. It will be possible to deploy in emergency units and in general in any type of mobile or static equipment. The sensing units will be highly portable thanks to their low size and low energy consumption. The complete system will be scalable in terms of complexity and cost and will offer very high precision on both the measurement and the location of the radiation. The modularity and flexibility of the system will allow for a realistic introduction to the market. Authorities may start with a

  3. Real-time Forensic Disaster Analysis

    Wenzel, F.; Daniell, J.; Khazai, B.; Mühr, B.; Kunz-Plapp, T.; Markus, M.; Vervaeck, A.


    The Center for Disaster Management and Risk Reduction Technology (CEDIM, - an interdisciplinary research center founded by the German Research Centre for Geoscience (GFZ) and Karlsruhe Institute of Technology (KIT) - has embarked on a new style of disaster research known as Forensic Disaster Analysis. The notion has been coined by the Integrated Research on Disaster Risk initiative (IRDR, launched by ICSU in 2010. It has been defined as an approach to studying natural disasters that aims at uncovering the root causes of disasters through in-depth investigations that go beyond the reconnaissance reports and case studies typically conducted after disasters. In adopting this comprehensive understanding of disasters CEDIM adds a real-time component to the assessment and evaluation process. By comprehensive we mean that most if not all relevant aspects of disasters are considered and jointly analysed. This includes the impact (human, economy, and infrastructure), comparisons with recent historic events, social vulnerability, reconstruction and long-term impacts on livelihood issues. The forensic disaster analysis research mode is thus best characterized as "event-based research" through systematic investigation of critical issues arising after a disaster across various inter-related areas. The forensic approach requires (a) availability of global data bases regarding previous earthquake losses, socio-economic parameters, building stock information, etc.; (b) leveraging platforms such as the EERI clearing house, relief-web, and the many sources of local and international sources where information is organized; and (c) rapid access to critical information (e.g., crowd sourcing techniques) to improve our understanding of the complex dynamics of disasters. The main scientific questions being addressed are: What are critical factors that control loss of life, of infrastructure, and for economy? What are the critical interactions

  4. Instrumentation development for real time brainwave monitoring.

    Anderson, Lawrence Frederick; Clough, Benjamin W.


    The human brain functions through a chemically-induced biological process which operates in a manner similar to electrical systems. The signal resulting from this biochemical process can actually be monitored and read using tools and having patterns similar to those found in electrical and electronics engineering. The primary signature of this electrical activity is the ''brain wave'', which looks remarkably similar to the output of many electrical systems. Likewise, the device currently used in medical arenas to read brain electrical activity is the electroencephalogram (EEG) which is synonymous with a multi-channel oscilloscope reading. Brain wave readings and recordings for medical purposes are traditionally taken in clinical settings such as hospitals, laboratories or diagnostic clinics. The signal is captured via externally applied scalp electrodes using semi-viscous gel to reduce impedance. The signal will be in the 10 to 100 microvolt range. In other instances, where surgeons are attempting to isolate particular types of minute brain signals, the electrodes may actually be temporarily implanted in the brain during a preliminary procedure. The current configurations of equipment required for EEGs involve large recording instruments, many electrodes, wires, and large amounts of hard disk space devoted to storing large files of brain wave data which are then eventually analyzed for patterns of concern. Advances in sensors, signal processing, data storage and microelectronics over the last decade would seem to have paved the way for the realization of devices capable of ''real time'' external monitoring, and possible assessment, of brain activity. A myriad of applications for such a capability are likewise presenting themselves, including the ability to assess brain functioning, level of functioning and malfunctioning. Our plan is to develop the sensors, signal processing, and portable instrumentation package which could

  5. Issues in Real-Time Data Management.


    2. Multiversion concurrency control [5] interprets write operations as the creation of new ver- sions of the items (in contrast to the update-in...features of optimistic (deferred writing, celayed selection of serialization order) and multiversion concurrency control. They do not present any...34 Multiversion Concurrency Control - Theory and Algorithms". ACM Transactions on Database Systems 8, 4 (December 1983), 465-484. 6. Buchman, A. P

  6. Wide Area Real Time Kinematic (WARTK): Usage of RTCM format, and real-time implementation

    Valls Moreno, Angel


    Nowadays GNSS1 enhancement techniques have reached a relevant impor- tance and are present in a wide variety of applications. During the last years the Research Group of Astronomy and Geomatics (gAGE) from the Tech- nical University of Catalonia (UPC) has developed and tested new satellite navigation techniques which allow the extension of local services based on the real-time carrier phase ambiguity resolution2 to wide area scale (i.e., base- lines between the rover and reference stations gr...

  7. Real time UAV autonomy through offline calculations

    Jung, Sunghun

    . Once one or several targets are detected, UAVs near the target are manipulated to approach to the target. If the number of detected targets is more than one, UAVs are evenly grouped to track targets. After a specific period of time, UAVs hand off and continue their original tasks. Thirdly, Emergency algorithm is generated to avoid losses of UAVs when UAVs have system failures. If one UAV is out of fuel or control during the mission, the Emergency algorithm brings the malfunctioning UAV to the point of departure and let the rest UAVs to continue an aerial reconnaissance. An UAV which finishes its task the earliest will continue to search a region which the failed UAV is supposed to search. In addition, Emergency algorithm prevents UAVs colliding into each other by using emergency altitude. Overall, the framework developed here facilitates the solution of several mission planning problems. The robustness built into our discretization of space and time permits feedback corrections on real-time to vehicle trajectories. The library of off-line solutions proposed and developed here minimizes computational overhead during operations.

  8. Real Time Flux Control in PM Motors

    Otaduy, P.J.


    Significant research at the Oak Ridge National Laboratory (ORNL) Power Electronics and Electric Machinery Research Center (PEEMRC) is being conducted to develop ways to increase (1) torque, (2) speed range, and (3) efficiency of traction electric motors for hybrid electric vehicles (HEV) within existing current and voltage bounds. Current is limited by the inverter semiconductor devices' capability and voltage is limited by the stator wire insulation's ability to withstand the maximum back-electromotive force (emf), which occurs at the upper end of the speed range. One research track has been to explore ways to control the path and magnitude of magnetic flux while the motor is operating. The phrase, real time flux control (RTFC), refers to this mode of operation in which system parameters are changed while the motor is operating to improve its performance and speed range. RTFC has potential to meet an increased torque demand by introducing additional flux through the main air gap from an external source. It can augment the speed range by diverting flux away from the main air gap to reduce back-emf at high speeds. Conventional RTFC technology is known as vector control [1]. Vector control decomposes the stator current into two components; one that produces torque and a second that opposes (weakens) the magnetic field generated by the rotor, thereby requiring more overall stator current and reducing the efficiency. Efficiency can be improved by selecting a RTFC method that reduces the back-emf without increasing the average current. This favors methods that use pulse currents or very low currents to achieve field weakening. Foremost in ORNL's effort to develop flux control is the work of J. S. Hsu. Early research [2,3] introduced direct control of air-gap flux in permanent magnet (PM) machines and demonstrated it with a flux-controlled generator. The configuration eliminates the problem of demagnetization because it diverts all the flux from the

  9. Non-contrast T1-mapping detects acute myocardial edema with high diagnostic accuracy: a comparison to T2-weighted cardiovascular magnetic resonance

    Ferreira Vanessa M


    Full Text Available Abstract Background T2w-CMR is used widely to assess myocardial edema. Quantitative T1-mapping is also sensitive to changes in free water content. We hypothesized that T1-mapping would have a higher diagnostic performance in detecting acute edema than dark-blood and bright-blood T2w-CMR. Methods We investigated 21 controls (55 ± 13 years and 21 patients (61 ± 10 years with Takotsubo cardiomyopathy or acute regional myocardial edema without infarction. CMR performed within 7 days included cine, T1-mapping using ShMOLLI, dark-blood T2-STIR, bright-blood ACUT2E and LGE imaging. We analyzed wall motion, myocardial T1 values and T2 signal intensity (SI ratio relative to both skeletal muscle and remote myocardium. Results All patients had acute cardiac symptoms, increased Troponin I (0.15-36.80 ug/L and acute wall motion abnormalities but no LGE. T1 was increased in patient segments with abnormal and normal wall motion compared to controls (1113 ± 94 ms, 1029 ± 59 ms and 944 ± 17 ms, respectively; p  Conclusions Non-contrast T1-mapping using ShMOLLI is a novel method for objectively detecting myocardial edema with a high diagnostic performance. T1-mapping may serve as a complementary technique to T2-weighted imaging for assessing myocardial edema in ischemic and non-ischemic heart disease, such as quantifying area-at-risk and diagnosing myocarditis.

  10. PRIMAS: real-time image-based motion measurement system

    Furnee, E. Hans


    The PRIMAS system derives from a long line of development at Delft University of Technology , originating from [1] with subsequent innovations such as strobed illumination (1974) of reflective markers, to obtain the simultaneous, equidistant, periodic sampling of all marker positions; real-time estimation of the marker centroids from the full, digitized, contours (1984) to retain the on-line data reduction, while enhancing the resolution; interfacing to industry-standard AT type personal computers, with modest disk requirements and no buffering, even for long data runs; 100 Hz, 0.1 ms integration time, electronically-shuttered TV cameras, to get an optimum marker contrast in high ambient or outdoor light conditions (1986). System specifications include a precision of typ. 1:18000 (X) for 2-D coordinate noise or repeatability. With the 100 Hz sample rate this implies an unprecedented spatio-temporal resolution [2]. This favors 3-D reconstruction, as well as a low noise propagation in the estimation of first and higher order derivatives, as are routinely required in biomechanics analysis. The latest feature is real-time marker identification by a software module within the data acquisition program. This option, for the not too complex situations, is feasible only by the data reduction inherent in on-line marker centroid processing. The 3-D calibration, reconstruction and further analytical and display programs are available in the ASYST 3.2 Scientific Language System. A source code option caters for customer extensions. The internal VME/VSB system bus allows the basic dual or quad camera 3-D systems to be readily expanded to larger configurations.

  11. On the Physiology of Normal Swallowing as Revealed by Magnetic Resonance Imaging in Real Time

    Arno Olthoff


    Full Text Available The aim of this study was to assess the physiology of normal swallowing using recent advances in real-time magnetic resonance imaging (MRI. Therefore ten young healthy subjects underwent real-time MRI and flexible endoscopic evaluations of swallowing (FEES with thickened pineapple juice as oral contrast bolus. MRI movies were recorded in sagittal, coronal, and axial orientations during successive swallows at about 25 frames per second. Intermeasurement variation was analyzed and comparisons between real-time MRI and FEES were performed. Twelve distinct swallowing events could be quantified by real-time MRI (start time, end time, and duration. These included five valve functions: oro-velar opening, velo-pharyngeal closure, glottal closure, epiglottic retroflexion, and esophageal opening; three bolus transports: oro-velar transit, pharyngeal delay, pharyngeal transit; and four additional events: laryngeal ascent, laryngeal descent, vallecular, and piriform sinus filling and pharyngeal constriction. Repetitive measurements confirmed the general reliability of the MRI method with only two significant differences for the start times of the velo-pharyngeal closure (t(8=-2.4, P≤0.046 and laryngeal ascent (t(8=-2.6, P≤0.031. The duration of the velo-pharyngeal closure was significantly longer in real-time MRI compared to FEES (t(8=-3.3, P≤0.011. Real-time MRI emerges as a simple, robust, and reliable tool for obtaining comprehensive functional and anatomical information about the swallowing process.

  12. RealTimeFrame – A Real Time Processing Framework for Medical Video Sequences

    S. Gross


    Full Text Available Imaging technology is highly important in today’s medical environments. It provides information upon which the accuracy of the diagnosis and consequently the wellbeing of the patient rely. Increasing the quality and significance of medical image data is therefore one the aims of scientific research and development. We introduce an integrated hardware and software framework for real time image processing in medical environments, which we call RealTimeFrame. Our project is designed to offer flexibility, easy expandability and high performance. We use standard personal computer hardware to run our multithreaded software. A frame grabber card is used to capture video signals from medical imaging systems. A modular, user-defined process chain performs arbitrary manipulations on the image data. The graphical user interface offers configuration options and displays the processed image in either window or full screen mode. Image source and processing routines are encapsulated in dynamic library modules for easy functionality extension without recompilation of the entire software framework. Documented template modules for sources and processing steps are part of the software’s source code.

  13. A real-time transaction service for grid computing

    Tang Feilong; Li Minglu; Joshua Huang Zhexue; Frank Tong; Cao Jian


    A real-time transaction service aims at ensuring the consistency of real-time and transactional Grid applications. This paper proposes an efficient real-time transaction service (RTTS). It provides abilities to discover qualified services, I.e., participants, to execute specified sub-transactions, coordinate real-time Grid transactions, calculate deadline and assign priority for scheduling concurrent transactions. The service discovery adopts the two-level registry mechanismto adapt to transient Grid services. The coordination algorithm invokes multiplefunctional alternative services for each sub-transaction so that it remarkablyimproves the successful ratio of real-time transactions. The experiment result shows that the RTTS can well coordinate real-time transactions for Grid service environment and shield users from the complex process.

  14. Sentiment analysis on students’ real-time feedback

    Altrabsheh, Nabeela


    Previous literature identifies that students’ real-time feedback is important in the learning process. There are numerous studies that have collected students’ feedback in real time. However, they include several limitations of which the most important is analysing the feedback. In this thesis, we address these limitations by proposing a system that will automatically analyse students’ feedback in real time and present the analysis results to the lecturer. To create such a system, we propose ...

  15. Advanced real-time manipulation of video streams

    Herling, Jan


    Diminished Reality is a new fascinating technology that removes real-world content from live video streams. This sensational live video manipulation actually removes real objects and generates a coherent video stream in real-time. Viewers cannot detect modified content. Existing approaches are restricted to moving objects and static or almost static cameras and do not allow real-time manipulation of video content. Jan Herling presents a new and innovative approach for real-time object removal with arbitrary camera movements.

  16. Visualization of swallowing using real-time TrueFISP MR fluoroscopy

    Barkhausen, Joerg; Goyen, Mathias; Lauenstein, Thomas; Debatin, Joerg F. [Department of Diagnostic Radiology, University Hospital Essen (Germany); Winterfeld, F. von; Arweiler-Harbeck, Diana [Department of Otorhinolaryngology, University Hospital Essen (Germany)


    The aim of this study was to evaluate the ability of different real-time true fast imaging with steady precession (TrueFISP) sequences regarding their ability to depict the swallowing process and delineate oropharyngeal pathologies in patients with dysphagia. Real-time TrueFISP visualization of swallowing was performed in 8 volunteers and 6 patients with dysphagia using a 1.5 T scanner (Magnetom Sonata, Siemens, Erlangen Germany) equipped with high-performance gradients (amplitude 40 mT/m). Image quality of four different real-time TrueFISP sequences (TR 2.2-3.0 ms, TE 1.1-1.5 ms, matrix 63 x 128-135 x 256, field of view 250 mm{sup 2}, acquisition time per image 139-405 ms) was evaluated. Water, yoghurt, and semolina pudding were assessed as oral contrast agents. Functional exploration of the oropharyngeal apparatus was best possible using the fastest real-time TrueFISP sequence (TR 2.2 ms, TE 1.1 ms, matrix 63 x 128). Increased acquisition time resulted in blurring of anatomical structures. As the image contrast of TrueFISP sequences depends on T2/T1 properties, all tested foodstuff were well suited as oral contrast agents, but image quality was best using semolina pudding. Real-time visualization of swallowing is possible using real-time TrueFISP sequences in conjunction with oral contrast agents. For the functional exploration of swallowing high temporal resolution is more crucial than spatial resolution. (orig.)

  17. 实时三维斑点追踪成像技术评价冠状动脉狭窄患者左心室整体及局部心肌收缩功能%Evaluation of globle and regional left ventricular myocardial systolic function in patients with coronary stenosis by real-time three-dimensional speckle tracking imaging

    陈莹; 刘昕; 郭淑芹


    Objective To explore the value of real‐time three‐dimensional speckle tracking imaging (RT‐3D‐STI) in the early detection of globle and regional left ventricular myocardial systolic function in patients of coronary stenosis without regional wall motion abnormality. Methods 64 coronary stenosis patients without regional wall motion abnormality were divided into 2 groups according to angiography (CAG):without coronary stenosis group( n = 20) and coronary stenosis group ( n = 44), and all the myocardial segments of the patients were divided into 5 groups:without coronary stenosis group normal myocardial segments ( n = 340 ), coronary stenosis group normal myocardial segments ( n = 235 ), mild coronary stenosis myocardial segments( n = 126), moderate coronary stenosis myocardial segments( n =213) and severe coronary stenosis myocardial segments( n =174). Real‐time three‐dimensional full volume of left ventricle was obtained, left ventricular global area strain (GAS)and regional area strain(AS) of 17 myocardial segments, etc, were measured by RT‐3D‐STI respectively. The parameters between the two groups and among the five sub groups were compared, the correlation between GAS and coronary artery Gensini score was also analyzed. Results GAS in coronary stenosis group significantly reduced compared with without coronary stenosis group( P 0 0.5) S.egmental AS in moderate and severe coronary stenosis myocardial segments significantly reduced ( P < 0.05 ), and that in severe coronary stenosis myocardial segments was lower than that in moderate coronary stenosis myocardial segments, the differences were statistically significant ( P < 0.05 ). In addition, GAS was significantly correlated with coronary artery Gensini score( r =0.828, P <0.01). Conclusions RT‐3D‐STI can quantitatively assess the early changes of left ventricular globle and regional myocardial systolic function in patients with coronary stenosis.%目的:探讨实时三

  18. Real Time Synchronization for Creativity in Distributed Innovation Teams

    Peitersen, Dennis Kjaersgaard; Dolog, Peter; Pedersen, Esben Staunsbjerg


    In this paper we introduce a synchronization approach for real time collaborative sketching for creativity in distributed innovation teams. We base our approach on reverse AJAX. This way we ensure scalable solution for real time drawing and sketching important in creativity settings.......In this paper we introduce a synchronization approach for real time collaborative sketching for creativity in distributed innovation teams. We base our approach on reverse AJAX. This way we ensure scalable solution for real time drawing and sketching important in creativity settings....

  19. Real Time Synchronization for Creativity in Distributed Innovation Teams

    Peitersen, Dennis Kjaersgaard; Dolog, Peter; Pedersen, Esben Staunsbjerg


    In this paper we introduce a synchronization approach for real time collaborative sketching for creativity in distributed innovation teams. We base our approach on reverse AJAX. This way we ensure scalable solution for real time drawing and sketching important in creativity settings.......In this paper we introduce a synchronization approach for real time collaborative sketching for creativity in distributed innovation teams. We base our approach on reverse AJAX. This way we ensure scalable solution for real time drawing and sketching important in creativity settings....

  20. Building Real-Time Collaborative Applications with a Federated Architecture

    Pablo Ojanguren-Menendez


    Full Text Available Real-time collaboration is being offered by multiple libraries and APIs (Google Drive Real-time API, Microsoft Real-Time Communications API, TogetherJS, ShareJS, rapidly becoming a mainstream option for webservices developers. However, they are offered as centralised services running in a single server, regardless if they are free/open source or proprietary software. After re-engineering Apache Wave (former Google Wave, we can now provide the first decentralised and federated free/open source alternative. The new API allows to develop new real-time collaborative web applications in both JavaScript and Java environments.

  1. Verifying real-time systems against scenario-based requirements

    Larsen, Kim Guldstrand; Li, Shuhao; Nielsen, Brian;


    subset of the LSC language. By equivalently translating an LSC chart into an observer TA and then non-intrusively composing this observer with the original system model, the problem of verifying a real-time system against a scenario-based requirement reduces to a classical real-time model checking......We propose an approach to automatic verification of real-time systems against scenario-based requirements. A real-time system is modeled as a network of Timed Automata (TA), and a scenario-based requirement is specified as a Live Sequence Chart (LSC). We define a trace-based semantics for a kernel...

  2. Unified Modeling of Complex Real-Time Control Systems

    Hai, He; Chi-Lan, Cai


    Complex real-time control system is a software dense and algorithms dense system, which needs modern software engineering techniques to design. UML is an object-oriented industrial standard modeling language, used more and more in real-time domain. This paper first analyses the advantages and problems of using UML for real-time control systems design. Then, it proposes an extension of UML-RT to support time-continuous subsystems modeling. So we can unify modeling of complex real-time control systems on UML-RT platform, from requirement analysis, model design, simulation, until generation code.

  3. Dual-phase contrast-enhancement multislice computed tomography imaging for the assessment of elderly patients with acute myocardial infarction after primary percutaneous coronary intervention

    Shaofeng Guan; Weiyi Fang; Xinkai Qu; Jianding Ye; Yan Shen; Jing Jiao


    Background Evaluation of acute myocardial infarction after reperfusion by dual phase contrast-enhancement multislice computed tomography (MSCT) was implicated in porcine model. There have been few attempts to use this diagnostic modality for the early assessment of coronary reperfusion in patients with ST-elevation myocardial infarction (STEMI), especially after primary percutaneous coronary intervention (PCI). In elderly patients with STEMI, the safety issues remain unknown. Methods Dual phase contrast-enhancement MSCT examinations were performed in 11 elderly patients (≥60 years old) with STEMI within one week after primary PCI. The presence, location and enhancement pattern on MSCT were evaluated. MSCT findings were compared with the catheter angiographic results and area under the curve of creatine kinase (CK) release. Serum creatinine level was recorded before and after MSCT scan. Results MSCT scans were successfully performed in all the patients. Early myocardial perfusion defect (early defect, ED) was detected in all of the 11 patients (100%) in the early phase of the contrast bolus (subendocardial ED in 10 patients and transmural in 1 patient). Mean CT attenuation value of ED was significantly different from CT attenuation value of remote myocardium (46±17 HU vs 104 ± 17 HU; P < 0.01). Location of ED area correlated well with infarction related artery territory on catheter angiography in all of the 11 patients (100%). On delayed phase of MSCT scan, different enhancement patterns were observed: isolated subendocardial late enhancement (LE) in 6 patients, subendocardial residual perfusion defect (RD) and subepicardial LE in 1 patient, subendocardial RD in 4 patients. Infarct volume assessed by MSCT correlated well with area under the curve CK release (R=0.72, P < 0.01). Serum creatinine level after MSCT scan showed no difference with that before MSCT scan. Conclusion Dual phase MSCT could be safely implicated in elderly patients with STEMI. Variable

  4. Quantitative Myocardial Perfusion with Dynamic Contrast-Enhanced Imaging in MRI and CT: Theoretical Models and Current Implementation

    G. J. Pelgrim


    Full Text Available Technological advances in magnetic resonance imaging (MRI and computed tomography (CT, including higher spatial and temporal resolution, have made the prospect of performing absolute myocardial perfusion quantification possible, previously only achievable with positron emission tomography (PET. This could facilitate integration of myocardial perfusion biomarkers into the current workup for coronary artery disease (CAD, as MRI and CT systems are more widely available than PET scanners. Cardiac PET scanning remains expensive and is restricted by the requirement of a nearby cyclotron. Clinical evidence is needed to demonstrate that MRI and CT have similar accuracy for myocardial perfusion quantification as PET. However, lack of standardization of acquisition protocols and tracer kinetic model selection complicates comparison between different studies and modalities. The aim of this overview is to provide insight into the different tracer kinetic models for quantitative myocardial perfusion analysis and to address typical implementation issues in MRI and CT. We compare different models based on their theoretical derivations and present the respective consequences for MRI and CT acquisition parameters, highlighting the interplay between tracer kinetic modeling and acquisition settings.

  5. 76 FR 42536 - Real-Time System Management Information Program


    ... Federal Highway Administration 23 CFR Part 511 RIN 2125-AF19 Real-Time System Management Information... additional comments relating to the costs and benefits of the Real-Time System Management Information Program... System Management Information Program on November 8, 2010, at 75 FR 68418. The final rule document...

  6. 75 FR 68418 - Real-Time System Management Information Program


    ... Federal Highway Administration 23 CFR Part 511 RIN 2125-AF19 Real-Time System Management Information... System Management Information Program that provides, in all States, the capability to monitor, in real... traveler information. The purposes of the Real-Time System Management Information Program are to:...

  7. Real-Time PCR for Universal Phytoplasma Detection and Quantification

    Christensen, Nynne Meyn; Nyskjold, Henriette; Nicolaisen, Mogens


    Currently, the most efficient detection and precise quantification of phytoplasmas is by real-time PCR. Compared to nested PCR, this method is less sensitive to contamination and is less work intensive. Therefore, a universal real-time PCR method will be valuable in screening programs and in other...

  8. Real-Time Adaptation of Influence Strategies in Online Selling

    Kaptein, M.C.; Parvinen, P.


    Real-time adjustments in online selling are becoming increasingly common. In this paper we describe a novel method of real-time adaptation, and introduce influence strategies as a useful level of analysis for personalization of online selling. The proposed method incorporates three perspectives on r

  9. "Real-Time" Case Studies in Organizational Communication

    Long, Shawn D.


    This article presents an activity that integrates theory and application by examining the multiple communication events affecting a single organization in "real time" over the course of an academic term. The "real-time" case study (RTCS) avails students of the opportunity to examine organizational communication events as they are occurring in…

  10. RT-PLG: Real Time Process Log Generator

    Yahya, Bernardo Nugroho; Khosiawan, Yohanes; Choi, Woosik;


    . This paper aims to develop a real time process log generator for the usage of streaming process mining tool. The real time process log generator (RT-PLG) is constructed in an independent tool. Afterward, the RT-PLG is utilized to generate a synthetic log for streaming process mining. The tool has been...... evaluated using an existing simulation model....

  11. A Real-time Data Model Based on Temporal Data

    ZHANG Xiao-fang; LIU Yun-sheng


    Real-time database systems contain not only transaction timing constraints, but also data timing constraints. This paper discusses the temporal characteristics of data in real-time databases and offers a definition of absolute and relative temporal consistency. In real-time database systems, it is often the case that the policies of transaction schedules only consider the deadline of real-time transactions, making it insufficient to ensure temporal correctness of transactions. A policy is given by considering both the deadlines of transactions and the "data deadline" to schedule real-time transactions. A real-time relational data model and a real-time relational algebra based on the characteristics of temporal data are also proposed. In this model, the temporal data has not only corresponding values, but also validity intervals corresponding to the data values. At the same time, this model is able to keep historical data values. When validity interval of a relation is[NOW,NOW], real-time relational algebra will transform to traditional relational algebra.

  12. Quantitation of viral load using real-time amplification techniques

    Niesters, H G


    Real-time PCR amplification techniques are currently used to determine the viral load in clinical samples for an increasing number of targets. Real-time PCR reduces the time necessary to generate results after amplification. In-house developed PCR and nucleic acid sequence-based amplification (NASBA

  13. Intelligent, Real-Time Problem Solving. Phase 3


    approach, and to develop a heuristic algorithm for design-to-time real-time scheduling. E .velopes. During Phase III we extended our work on the real...the anytime algorithm approach, and presents a heuristic algorithm for design-to-time real-time scheduling. The methodology is known as design-to

  14. Distributed, Embedded and Real-time Java Systems

    Wellings, Andy


    Research on real-time Java technology has been prolific over the past decade, leading to a large number of corresponding hardware and software solutions, and frameworks for distributed and embedded real-time Java systems.  This book is aimed primarily at researchers in real-time embedded systems, particularly those who wish to understand the current state of the art in using Java in this domain.  Much of the work in real-time distributed, embedded and real-time Java has focused on the Real-time Specification for Java (RTSJ) as the underlying base technology, and consequently many of the Chapters in this book address issues with, or solve problems using, this framework. Describes innovative techniques in: scheduling, memory management, quality of service and communication systems supporting real-time Java applications; Includes coverage of multiprocessor embedded systems and parallel programming; Discusses state-of-the-art resource management for embedded systems, including Java’s real-time garbage collect...

  15. Real time ray tracing of skeletal implicit surfaces

    Rouiller, Olivier; Bærentzen, Jakob Andreas

    Modeling and rendering in real time is usually done via rasterization of polygonal meshes. We present a method to model with skeletal implicit surfaces and an algorithm to ray trace these surfaces in real time in the GPU. Our skeletal representation of the surfaces allows to create smooth models...

  16. Operational and logical semantics for polling real-time systems

    Anders, P.R.; Dierks, Henning; Fehnker, Ansgar; Rischel, H.; Fehnker, Ansgar; Mader, Angelika H.; Vaandrager, Frits

    PLC-Automata are a class of real-time automata suitable to describe the behavior of polling real-time systems. PLC-Automata can be compiled to source code for PLCs, a hardware widely used in industry to control processes. Also, PLC-Automata have been equipped with a logical and operational

  17. Ab initio quantum-enhanced optical phase estimation using real-time feedback control

    Berni, Adriano; Gehring, Tobias; Nielsen, Bo Melholt


    as demonstrated in a variety of different optical systems(3-8). Most of these accounts, however, deal with the measurement of a very small shift of an already known phase, which is in stark contrast to ab initio phase estimation where the initial phase is unknown(9-12). Here, we report on the realization...... of a quantum-enhanced and fully deterministic ab initio phase estimation protocol based on real-time feedback control. Using robust squeezed states of light combined with a real-time Bayesian adaptive estimation algorithm, we demonstrate deterministic phase estimation with a precision beyond the quantum shot...

  18. Real-time geometric scene estimation for RGBD images using a 3D box shape grammar

    Willis, Andrew R.; Brink, Kevin M.


    This article describes a novel real-time algorithm for the purpose of extracting box-like structures from RGBD image data. In contrast to conventional approaches, the proposed algorithm includes two novel attributes: (1) it divides the geometric estimation procedure into subroutines having atomic incremental computational costs, and (2) it uses a generative "Block World" perceptual model that infers both concave and convex box elements from detection of primitive box substructures. The end result is an efficient geometry processing engine suitable for use in real-time embedded systems such as those on an UAVs where it is intended to be an integral component for robotic navigation and mapping applications.

  19. Survey of real-time processing systems for big data

    Liu, Xiufeng; Lftikhar, Nadeem; Xie, Xike


    In recent years, real-time processing and analytics systems for big data–in the context of Business Intelligence (BI)–have received a growing attention. The traditional BI platforms that perform regular updates on daily, weekly or monthly basis are no longer adequate to satisfy the fast......-changing business environments. However, due to the nature of big data, it has become a challenge to achieve the real-time capability using the traditional technologies. The recent distributed computing technology, MapReduce, provides off-the-shelf high scalability that can significantly shorten the processing time...... for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  20. Recent achievements in real-time computational seismology in Taiwan

    Lee, S.; Liang, W.; Huang, B.


    Real-time computational seismology is currently possible to be achieved which needs highly connection between seismic database and high performance computing. We have developed a real-time moment tensor monitoring system (RMT) by using continuous BATS records and moment tensor inversion (CMT) technique. The real-time online earthquake simulation service is also ready to open for researchers and public earthquake science education (ROS). Combine RMT with ROS, the earthquake report based on computational seismology can provide within 5 minutes after an earthquake occurred (RMT obtains point source information < 120 sec; ROS completes a 3D simulation < 3 minutes). All of these computational results are posted on the internet in real-time now. For more information, welcome to visit real-time computational seismology earthquake report webpage (RCS).

  1. Real-time feedback from iterative electronic structure calculations

    Vaucher, Alain C; Reiher, Markus


    Real-time feedback from iterative electronic structure calculations requires to mediate between the inherently unpredictable execution times of the iterative algorithm employed and the necessity to provide data in fixed and short time intervals for real-time rendering. We introduce the concept of a mediator as a component able to deal with infrequent and unpredictable reference data to generate reliable feedback. In the context of real-time quantum chemistry, the mediator takes the form of a surrogate potential that has the same local shape as the first-principles potential and can be evaluated efficiently to deliver atomic forces as real-time feedback. The surrogate potential is updated continuously by electronic structure calculations and guarantees to provide a reliable response to the operator for any molecular structure. To demonstrate the application of iterative electronic structure methods in real-time reactivity exploration, we implement self-consistent semi-empirical methods as the data source and a...

  2. Self-Organization in Embedded Real-Time Systems

    Brinkschulte, Uwe; Rettberg, Achim


    This book describes the emerging field of self-organizing, multicore, distributed and real-time embedded systems.  Self-organization of both hardware and software can be a key technique to handle the growing complexity of modern computing systems. Distributed systems running hundreds of tasks on dozens of processors, each equipped with multiple cores, requires self-organization principles to ensure efficient and reliable operation. This book addresses various, so-called Self-X features such as self-configuration, self-optimization, self-adaptation, self-healing and self-protection. Presents open components for embedded real-time adaptive and self-organizing applications; Describes innovative techniques in: scheduling, memory management, quality of service, communications supporting organic real-time applications; Covers multi-/many-core embedded systems supporting real-time adaptive systems and power-aware, adaptive hardware and software systems; Includes case studies of open embedded real-time self-organizi...

  3. Academic Training: Real Time Process Control - Lecture series

    Françoise Benz


    ACADEMIC TRAINING LECTURE REGULAR PROGRAMME 7, 8 and 9 June From 11:00 hrs to 12:00 hrs - Main Auditorium bldg. 500 Real Time Process Control T. Riesco / CERN-TS What exactly is meant by Real-time? There are several definitions of real-time, most of them contradictory. Unfortunately the topic is controversial, and there does not seem to be 100% agreement over the terminology. Real-time applications are becoming increasingly important in our daily lives and can be found in diverse environments such as the automatic braking system on an automobile, a lottery ticket system, or robotic environmental samplers on a space station. These lectures will introduce concepts and theory like basic concepts timing constraints, task scheduling, periodic server mechanisms, hard and soft real-time.ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127

  4. Ambiguity and Concepts in Real Time Online Internet Traffic Classification

    Hamza Awad Hamza Ibrahim


    Full Text Available Internet traffic classification gained significant attention in the last few years. Identifying the Internet applications in the real time is one of the most significant challenges in network traffic classification. Most of the proposed classification methods are limited to offline classification and cannot support online classification. This paper aims to highlight the ambiguity in the definition of online classification. Therefore, some of the previous online classification works are discussed and analyzed. This analysing is to check how far the real time online classification was achieved. The results indicate that most of the previous works consider a real Internet traffic but did not consider a real time online classification. In addition, the paper provides a real time classifier which was proposed and used in [1] [2] [3], to show how to perform a real time online classification.

  5. Survey of real-time processing systems for big data

    Iftikhar, Nadeem


    In recent years, real-time processing and analytics systems for big data–in the context of Business Intelligence (BI)–have received a growing attention. The traditional BI platforms that perform regular updates on daily, weekly or monthly basis are no longer adequate to satisfy the fast......-changing business environments. However, due to the nature of big data, it has become a challenge to achieve the real-time capability using the traditional technologies. The recent distributed computing technology, MapReduce, provides off-the-shelf high scalability that can significantly shorten the processing time...... for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  6. Assessment of the ability of myocardial contrast echocardiography with harmonic power Doppler imaging to identify perfusion abnormalities in patients with Kawasaki disease at rest and during dipyridamole stress.

    Ishii, M; Himeno, W; Sawa, M; Iemura, M; Furui, J; Muta, H; Sugahara, Y; Egami, K; Akagi, T; Ishibashi, M; Kato, H


    The aim of our study was to assess the ability of myocardial contrast echocardiography (MCE) with harmonic power Doppler imaging (HPDI) to identify perfusion abnormalities in patients with Kawasaki disease at rest and during pharmacological stress imaging with dipyridamole. Results were compared with those of 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) imaging as the clinical reference standard. MCE with HPDI was performed on 20 patients with a history of Kawasaki disease. Images were obtained at baseline and during dipyridamole infusion (0.56 mg x kg(-1)) in the apical two- and four-chamber views. Myocardial opacification suitable for the analysis was obtained in all patients. Nine patients with stenotic lesions had a reversible defect after dipyridamole infusion detected by both MCE with HPDI and SPECT, and 3 patients with a history of myocardial infarction had a partially or completely irreversible defect detected by both methods. Three patients with coronary aneurysm without stenotic lesion, 4 patients with regressed coronary aneurysm, and 2 patients with normal coronary artery in acute phase also had normal perfusion at rest and after pharmacological stress by both methods. A 96% concordance (kappa = 0.87) was obtained when comparing the respective segmental perfusion scores using the two methods at baseline, and an 86% concordance (kappa = 0.81) was obtained at postdipyridamole infusion. After combining baseline and postdipyridamole images, each segment was labeled as having normal perfusion, irreversible defects, or reversible defects. Using these classifications, concordance for the two methods was 92% (kappa = 0.87). MCE with HPDI is a safe and feasible method by which to detect asymptomatic ischemia due to severe stenotic lesion, and it may be an important addition to the modalities used to identify patients at risk for myocardial infarction as a complication of Kawasaki disease.

  7. New real-time image processing system for IRFPA

    WANG Bing-jian; LIU Shang-qian; CHENG Yu-bao


    Influenced by detectors' material,manufacturing technology etc,every detector in infrared focal plane array (IRFPA) will output different voltages even if their input radiation flux is the same.And this is called non-uniformity of IRFPA.At the same time,the high background temperature,low temperature difference between targets and background and the low responsivity of IRFPA result in low contrast of infrared images.So non-uniformity correction and image enhancement are important techniques for IRFPA imaging system.This paper proposes a new real-time infrared image processing system based on Field Programmable Gate Array(FPGA).The system implements non-uniformity correction,image enhancement and video synthesization etc.By using parallel architecture and pipeline technique,the system processing speed is as high as 50Mx12bits per second.It is appropriate greatly to a large IRFPA and a high frame frequency IRFPA imaging system.The system is miniatured in one FPGA.

  8. In vivo real-time cavitation imaging in moving organs

    Arnal, B.; Baranger, J.; Demene, C.; Tanter, M.; Pernot, M.


    The stochastic nature of cavitation implies visualization of the cavitation cloud in real-time and in a discriminative manner for the safe use of focused ultrasound therapy. This visualization is sometimes possible with standard echography, but it strongly depends on the quality of the scanner, and is hindered by difficulty in discriminating from highly reflecting tissue signals in different organs. A specific approach would then permit clear validation of the cavitation position and activity. Detecting signals from a specific source with high sensitivity is a major problem in ultrasound imaging. Based on plane or diverging wave sonications, ultrafast ultrasonic imaging dramatically increases temporal resolution, and the larger amount of acquired data permits increased sensitivity in Doppler imaging. Here, we investigate a spatiotemporal singular value decomposition of ultrafast radiofrequency data to discriminate bubble clouds from tissue based on their different spatiotemporal motion and echogenicity during histotripsy. We introduce an automation to determine the parameters of this filtering. This method clearly outperforms standard temporal filtering techniques with a bubble to tissue contrast of at least 20 dB in vitro in a moving phantom and in vivo in porcine liver.

  9. Real-time functional architecture of visual word recognition.

    Whiting, Caroline; Shtyrov, Yury; Marslen-Wilson, William


    Despite a century of research into visual word recognition, basic questions remain unresolved about the functional architecture of the process that maps visual inputs from orthographic analysis onto lexical form and meaning and about the units of analysis in terms of which these processes are conducted. Here we use magnetoencephalography, supported by a masked priming behavioral study, to address these questions using contrasting sets of simple (walk), complex (swimmer), and pseudo-complex (corner) forms. Early analyses of orthographic structure, detectable in bilateral posterior temporal regions within a 150-230 msec time frame, are shown to segment the visual input into linguistic substrings (words and morphemes) that trigger lexical access in left middle temporal locations from 300 msec. These are primarily feedforward processes and are not initially constrained by lexical-level variables. Lexical constraints become significant from 390 msec, in both simple and complex words, with increased processing of pseudowords and pseudo-complex forms. These results, consistent with morpho-orthographic models based on masked priming data, map out the real-time functional architecture of visual word recognition, establishing basic feedforward processing relationships between orthographic form, morphological structure, and lexical meaning.

  10. A Real-Time Lane Detection Algorithm Based on Intelligent CCD Parameters Regulation

    Ping-shu Ge


    Full Text Available Lane departure warning system (LDWS has been regarded as an efficient method to lessen the damages of road traffic accident resulting from driver fatigue or inattention. Lane detection is one of the key techniques for LDWS. To overcome the contradiction between complexity of algorithm and the real-time requirement for vehicle onboard system, this paper introduces a new lane detection method based on intelligent CCD parameters regulation. In order to improve the real-time capability of the system, a CCD parameters regulating method is proposed which enhances the contrast between lane line and road surfaces and reduces image noise, so it lays a good foundation for the following lane detection. Hough transform algorithm is improved by selection and classification of seed points. Finally the lane line is extracted through some restrictions. Experimental results verify the effectiveness of the proposed method, which improves not only real-time capability but also the accuracy of the system.

  11. Scheduling Non-stationary Bursts of Real-time and Non-real-time Traffic in ATM Networks


    The problem of scheduling real-time and non-real-time traffic in an ATM switch multiplexor when bursts of either type of traffic occur is studied. The scheduling algorithms studied are: Queue Length Threshold (QLT) and Minimum Laxity Threshold (MLT). Analytic results based on Markov Chains are used. In addition the results are compared with an optimal (but impractical) scheduling determined via dynamic programming. Dynamic programming is used in this paper to show that MLT gives a near optimal performance trade-off between real-time and non-real-time traffic for constant arrival rates. The trade-off QLT allows is not close to optimal. For non-real-time bursts MLT still gives a close to optimal trade-off. For real-time bursts the trade-off MLT allows between real-time and non-real-time traffic is not as close to optimal, but even where the MLT trade-off is not near optimal, the QLT trade-off is much worse than the MLT trade-off.

  12. Reviewing real-time performance of nuclear reactor safety systems

    Preckshot, G.G. [Lawrence Livermore National Lab., CA (United States)


    The purpose of this paper is to recommend regulatory guidance for reviewers examining real-time performance of computer-based safety systems used in nuclear power plants. Three areas of guidance are covered in this report. The first area covers how to determine if, when, and what prototypes should be required of developers to make a convincing demonstration that specific problems have been solved or that performance goals have been met. The second area has recommendations for timing analyses that will prove that the real-time system will meet its safety-imposed deadlines. The third area has description of means for assessing expected or actual real-time performance before, during, and after development is completed. To ensure that the delivered real-time software product meets performance goals, the paper recommends certain types of code-execution and communications scheduling. Technical background is provided in the appendix on methods of timing analysis, scheduling real-time computations, prototyping, real-time software development approaches, modeling and measurement, and real-time operating systems.

  13. Space Shuttle Main Engine real time stability analysis

    Kuo, F. Y.


    The Space Shuttle Main Engine (SSME) is a reusable, high performance, liquid rocket engine with variable thrust. The engine control system continuously monitors the engine parameters and issues propellant valve control signals in accordance with the thrust and mixture ratio commands. A real time engine simulation lab was installed at MSFC to verify flight software and to perform engine dynamic analysis. A real time engine model was developed on the AD100 computer system. This model provides sufficient fidelity on the dynamics of major engine components and yet simplified enough to be executed in real time. The hardware-in-the-loop type simulation and analysis becomes necessary as NASA is continuously improving the SSME technology, some with significant changes in the dynamics of the engine. The many issues of interfaces between new components and the engine can be better understood and be resolved prior to the firing of the engine. In this paper, the SSME real time simulation Lab at the MSFC, the SSME real time model, SSME engine and control system stability analysis, both in real time and non-real time is presented.

  14. A new method to study changes in microvascular blood volume in muscle and adipose tissue: Real time imaging in humans and rat

    Sjøberg, Kim Anker; Rattigan, Stephen; Hiscock, Natalie J


    We employed and evaluated a new application of contrast enhanced ultrasound for real time imaging of changes in microvascular blood volume (MVB) in tissues in females, males and rat. Continuous real time imaging was performed using contrast enhanced ultrasound to quantify infused gas filled micro...

  15. Screening and reconstruction of real-time traffic data

    裴玉龙; 马骥


    The quality of real-time traffic information is of the great importance, therefore the factors having effect on traffic characteristics are analyzed in general, and the necessities of real-time data processing are summarized. The identification and reconstruction of real-time traffic data are analyzed using Kalman filter equation and statistical approach. Four methods for ITS (Intelligent transportation system) detector data screening in traffic management systems are discussed in detail. Meanwhile traffic data examinations are discussed with solutions formulated through analysis, and recommendations are made for information collection and data management in future.

  16. Real-time simulation of hand motion for prosthesis control.

    Blana, Dimitra; Chadwick, Edward K; van den Bogert, Antonie J; Murray, Wendy M


    Individuals with hand amputation suffer substantial loss of independence. Performance of sophisticated prostheses is limited by the ability to control them. To achieve natural and simultaneous control of all wrist and hand motions, we propose to use real-time biomechanical simulation to map between residual EMG and motions of the intact hand. Here we describe a musculoskeletal model of the hand using only extrinsic muscles to determine whether real-time performance is possible. Simulation is 1.3 times faster than real time, but the model is locally unstable. Methods are discussed to increase stability and make this approach suitable for prosthesis control.

  17. Real-Time Obstacle Detection Approach using Stereoscopic Images

    Nadia Baha


    Full Text Available In this paper, we propose a new and simple approach to obstacle and free space detection in an indoor and outdoor environment in real-time using stereo vision as sensor. The real-time obstacle detection algorithm uses two dimensional disparity map to detect obstacles in the scene without constructing the ground plane. The proposed approach combines an accumulating and thresholding techniques to detect and cluster obstacle pixels into objects using a dense disparity map. The results from both analysis modules are combined to provide information of the free space. Experimental results are presented to show the effectiveness of the proposed method in real-time.

  18. Real-Time Mass Passenger Transport Network Optimization Problems


    The aim of Real-Time Mass Transport Vehicle Routing Problem (MTVRP) is to find a solution to route n vehicles in real time to pick up and deliver m passengers. This problem is described in the context of flexible large-scale mass transportation options that use new technologies for communication among passengers and vehicles. The solution of such a problem is relevant to future transportation options involving large scale real-time routing of shared-ride fleet transit vehicles. However, the g...

  19. The Durham adaptive optics real-time controller

    Basden, Alastair; Myers, Richard; Younger, Eddy


    The Durham adaptive optics real-time controller was initially a proof of concept design for a generic adaptive optics control system. It has since been developed into a modern and powerful CPU based real-time control system, capable of using hardware acceleration (including FPGAs and GPUs), based primarily around commercial off the shelf hardware. It is powerful enough to be used as the real-time controller for all currently planned 8~m class telescope adaptive optics systems. Here we give details of this controller and the concepts behind it, and report on performance including latency and jitter, which is less than 10~$\\mu$s for small adaptive optics systems.

  20. A framework to model real-time databases

    Idoudi, Nizar; Duvallet, Claude; Sadeg, Bruno; Bouaziz, Rafik; Gargouri, Faiez


    Real-time databases deal with time-constrained data and time-constrained transactions. The design of this kind of databases requires the introduction of new concepts to support both data structures and the dynamic behaviour of the database. In this paper, we give an overview about different aspects of real-time databases and we clarify requirements of their modelling. Then, we present a framework for real-time database design and describe its fundamental operations. A case study demonstrates the validity of the structural model and illustrates SQL queries and Java code generated from the classes of the model

  1. Real-time embedded systems design principles and engineering practices

    Fan, Xiaocong


    This book integrates new ideas and topics from real time systems, embedded systems, and software engineering to give a complete picture of the whole process of developing software for real-time embedded applications. You will not only gain a thorough understanding of concepts related to microprocessors, interrupts, and system boot process, appreciating the importance of real-time modeling and scheduling, but you will also learn software engineering practices such as model documentation, model analysis, design patterns, and standard conformance. This book is split into four parts to help you

  2. Ventricular septal rupture imaged with real-time three-dimensional transesophageal echocardiography: diagnosis at a glance.

    Squeri, Angelo; Conti, Rita; Bosi, Stefano


    Ventricular septal rupture is a rare complication of acute myocardial infarction and its diagnosis can be really challenging especially in the case of complex lesions. Echocardiography is the technique of choice for the detection of mechanical complications following myocardial infarction. The introduction of three-dimensional echocardiography offers new imaging possibilities with precise localization and easiest definition of the defect anatomy. This information is of paramount importance in the setting of a percutaneous closure procedure. We describe a case where real-time three-dimensional transesophageal echocardiography correctly defined the complex anatomy of a postmyocardial infarction septal defect with an associated pseudoaneurysm.

  3. Usage of the T{sub 1} effect of an iron oxide contrast agent in an animal model to quantify myocardial blood flow by MRI

    Luedemann, Lutz [Department of Radiology and Nuclear Medicine Charite-Universitaetmedizin Berlin, Campus Virchow-Klinikum (Germany)]. E-mail:; Schmitt, Boris [Department of Congenital Heart Disease, Deutsches Herzzentrum, Berlin (Germany); Podrabsky, Petr [Department of Radiology and Nuclear Medicine Charite-Universitaetmedizin Berlin, Campus Virchow-Klinikum (Germany); Schnackenburg, Bernhard [Philips Medical Systems, Hamburg (Germany); Boeck, Johannes [Department of Radiology and Nuclear Medicine Charite-Universitaetmedizin Berlin, Campus Virchow-Klinikum (Germany); Gutberlet, Matthias [Department of Radiology and Nuclear Medicine Charite-Universitaetmedizin Berlin, Campus Virchow-Klinikum (Germany)


    Background: To present a new method for fully quantitative analysis of myocardial blood flow (MBF) using magnetic resonance imaging. The first pass of an intravascular iron oxide contrast medium can be used to quantify myocardial perfusion. The technique was validated in an animal model using colored microspheres. Materials and methods: In six pigs, a tracking catheter was positioned in the left anterior descending artery (LAD). Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was performed on a 1.5-T scanner using a hybrid gradient-echo/echoplanar imaging (GRE-EPI) sequence. Regional myocardial blood flow (rMBF) was altered by either inducing vasodilatation with adenosine or creating coronary artery obstruction. The T{sub 1} effect of a superparamagnetic iron oxide-based contrast medium (Resovist[reg]) administered at a dose of 8 {mu}mol/kg was used. Upslope, time-to-peak and peak intensity were calculated from the signal intensity-time curves and absolute rMBF using the Kety-Schmidt equation; results were compared to those obtained using colored microspheres. Results: The mean rMBF calculated by MRI was 1.49 ({+-}6.91, quartile width) ml/min/g versus 3.21 ({+-}1.61) ml/min/g measured by means of microspheres under resting conditions. rMBF increased to a mean of 6.21 ({+-}2.83) ml/min/g versus 4.22 ({+-}1.70) ml/min/g under adenosine and was reduced to zero flow in total occlusion. Linear regression showed the best correlation for upslope (R = 0.714), time-to-peak (R = 0.626) and the Kety-Schmidt equation (R = 0.584). Conclusions: The T{sub 1} effect of an iron oxide-based contrast medium allows determination of rMBF when using the Kety-Schmidt equation. The results are similar to those obtained with the standard of reference, colored micropheres, but not better than the results of the semiquantitative approach.

  4. Tool for automatic real-time regional cardiac function analysis using HARP

    Abd-Elmoniem, Klaled Z.; Sampath, Smita; Osman, Nael F.; Prince, Jerry L.


    The FastHARP magnetic resonance pulse sequence can acquire taggged cardiac images at a rate of 45 ms per frame, enabling 7-20 harmonic phase (HARP) images per heartbeat per tag orientation. By switching the tag orientation every heartbeat, data from just two heartbeats can be used to compute in-plane quantities describing myocardial deformation, such as circumferential and radial strain. Standard HARP software, however, requries about one second to compute each strain image, which is not fast enough to keep up with the FastHARP pulse sequence. In this work, we have developed real-time algorithms for HARP processing of tagged MR images. The code was implemented along wiht a visualization tool that runs in conjunction with the FastHARP pulse sequence. HARP strain computations and display can now be carried out in real-time after a one heartbeat delay. The software is also fast enough to track and plot the time profile of strain of one or more points in the myocardium in real-time. Our software has now been integrated into a research testbed for magnetic resonance cardiac stress testing, contributing to the emerging suite of clinical cardiac MRI protocols.

  5. RadNet-Air Near Real Time Data

    U.S. Environmental Protection Agency — RadNet-Air is a national network of air monitoring stations that regularly collect air samples for near real time analysis of radioactivity. The data is transmitted...

  6. Estimating correlation for a real-time measure of connectivity.

    Arunkumar, Akhil; Panday, Ashish; Joshi, Bharat; Ravindran, Arun; Zaveri, Hitten P


    There has recently been considerable interest in connectivity analysis of fMRI and scalp and intracranial EEG time-series. The computational requirements of the pair-wise correlation (PWC), the core time-series measure used to estimate connectivity, presents a challenge to the real-time estimation of the PWC between all pairs of multiple time-series. We describe a parallel algorithm for computing PWC in real-time for streaming data from multiple channels. The algorithm was implemented on the Intel Xeon™ and IBM Cell Broadband Engine™ platforms. We evaluated time to estimate correlation for signals recorded with different acquisition parameters as a comparison to real-time constraints. We demonstrate that the execution time of these efficient implementations meet real-time constraints in most instances.

  7. True Time API Link (real time arrival info)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This link will take you to the site where you can create an account to access Port Authority's real time arrival information. To request access to Port Authority's...

  8. The Effects of Real-Time Interactive Multimedia Teleradiology System.

    Al-Safadi, Lilac


    This study describes the design of a real-time interactive multimedia teleradiology system and assesses how the system is used by referring physicians in point-of-care situations and supports or hinders aspects of physician-radiologist interaction. We developed a real-time multimedia teleradiology management system that automates the transfer of images and radiologists' reports and surveyed physicians to triangulate the findings and to verify the realism and results of the experiment. The web-based survey was delivered to 150 physicians from a range of specialties. The survey was completed by 72% of physicians. Data showed a correlation between rich interactivity, satisfaction, and effectiveness. The results of our experiments suggest that real-time multimedia teleradiology systems are valued by referring physicians and may have the potential for enhancing their practice and improving patient care and highlight the critical role of multimedia technologies to provide real-time multimode interactivity in current medical care.

  9. Hard-real-time resource management for autonomous spacecraft

    Gat, E.


    This paper describes tickets, a computational mechanism for hard-real-time autonomous resource management. Autonomous spacecraftcontrol can be considered abstractly as a computational process whose outputs are spacecraft commands.

  10. Real-Time Multi-Directional Equipment Site

    Federal Laboratory Consortium — As part of the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Program, Lehigh University has established the Real-Time Multi-Directional...

  11. UML statechart based rigorous modeling of real-time system

    LAI Ming-zhi; YOU Jin-yuan


    Rigorous modeling could ensure correctness and could verify a reduced cost in embedded real-time system development for models. Software methods are needed for rigorous modeling of embedded real-time systems. PVS is a formal method with precise syntax and semantics defined. System modeled by PVS specification could be verified by tools. Combining the widely used UML with PVS, this paper provides a novel modeling and verification approach for embedded real-time systems. In this approach, we provide 1 ) a time-extended UML statechart for modeling dynamic behavior of an embedded real-time system; 2) an approach to capture timed automata based semantics from a timed statechart; and 3) an algorithm to generate a finite state model expressed in PVS specification for model checking. The benefits of our approach include flexibility and user friendliness in modeling, extendability in formalization and verification content, and better performance. Time constraints are modeled and verified and is a highlight of this paper.

  12. Scheduling Algorithms Based on Weakly Hard Real-Time Constraints

    TU Gang (涂刚); YANG FuMin (阳富民); LU YanSheng (卢炎生)


    The problem of scheduling weakly hard real-time tasks is addressed in this paper.The paper first analyzes the characters ofμ-pattern and weakly hard real-time constraints, then,presents two scheduling algorithms, Meet Any Algorithm and Meet Row Algorithm, for weakly hard real-time systems. Different from traditional algorithms used to guarantee deadlines, Meet Any Algorithm and Meet Row Algorithm can guarantee both deadlines and constraints. Meet Any Algorithm and Meet Row Algorithm try to find out the probabilities of tasks breaking constraints and increase task's priority in advance, but not till the last moment. Simulation results show that these two algorithms are better than other scheduling algorithms dealing with constraints and can largely decrease worst-case computation time of real-time tasks.

  13. Comparison of conventional culture and real-time quantitative PCR ...


    Oct 28, 2009 ... Results of real-time PCR were compared to con- ventional analysis .... water bath (Selecta 40W power, 40 kHz ultrasound fre- quency). ..... mental distributions of Legionella strains in France are different. J. clin. Microbiol.

  14. NOAA Ship Nancy Foster Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Nancy Foster Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  15. NOAA Ship Oregon II Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oregon II Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  16. NOAA Ship Pisces Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Pisces Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  17. NOAA Ship Gordon Gunter Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Gordon Gunter Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  18. NOAA Ship Okeanos Explorer Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Okeanos Explorer Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System...

  19. NOAA Ship Rainier Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Rainier Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  20. Real-time water quality monitoring and providing water quality ...

    EPA and the U.S. Geological Survey (USGS) have initiated the “Village Blue” research project to provide real-time water quality monitoring data to the Baltimore community and increase public awareness about local water quality in Baltimore Harbor and the Chesapeake Bay. The Village Blue demonstration project complements work that a number of state and local organizations are doing to make Baltimore Harbor “swimmable and fishable” 2 by 2020. Village Blue is designed to build upon EPA’s “Village Green” project which provides real-time air quality information to communities in six locations across the country. The presentation, “Real-time water quality monitoring and providing water quality information to the Baltimore Community”, summarizes the Village Blue real-time water quality monitoring project being developed for the Baltimore Harbor.

  1. Decision graphs: a tool for developing real-time software

    Kozubal, A.J.


    The use of decision graphs in the preparation of, in particular, real-time software is briefly described. The usefulness of decision graphs in software design, testing, and maintenance is pointed out. 2 figures. (RWR)

  2. RadNet Real-Time Monitoring Spectrometry Data Inventory

    U.S. Environmental Protection Agency — The RadNet Real-Time Monitoring Spectrometry Data Inventory contains measured data used to identify and measure specific radioactive materials in the atmosphere at...

  3. Novel Real-Time Flight Envelope Monitoring System Project

    National Aeronautics and Space Administration — The proposed innovation is an aircraft flight envelope monitoring system that will provide real-time in-cockpit estimations of aircraft flight envelope boundaries,...

  4. Real-time Position Control of Concentric Tube Robots.

    Dupont, Pierre E; Lock, Jesse; Itkowitz, Brandon


    A novel approach to constructing robots is based on concentrically combining pre-curved elastic tubes. By rotating and extending the tubes with respect to each other, their curvatures interact elastically to position and orient the robot's tip, as well as to control the robot's shape along its length. Since these robots form slender curves, they are well suited for minimally invasive medical procedures. A substantial challenge to their practical use is the real-time solution of their kinematics that are described by differential equations with split boundary equations. This paper proposes a numerically efficient approach to real-time position control. It is shown that the forward kinematics are smooth functions that can be pre-computed and accurately approximated using Fourier series. The inverse kinematics can be solved in real time using root finding applied to the functional approximation. Experimental demonstration of real-time position control using this approach is also described.

  5. Novel Real-Time Flight Envelope Monitoring System Project

    National Aeronautics and Space Administration — The proposed innovation is an aircraft flight envelope monitoring system that will provide real-time in-cockpit estimations of aircraft flight envelope boundaries....

  6. Real Time Scheduling Services for Distributed RT-CORBA Applications

    Bineta Tresa Mathew


    Full Text Available Distributed computing environment is flexible to control in complex embedded systems and their software components gain complexity when these systems are equipped with many microcontrollers and software object which covers diverse platforms, this system is called as DRE system. These DRE systems need new inter-object communication solution thus QoS-enabled middleware services and mechanisms have begun to emerge. Real-time application domain benefit from flexible and open distributed architectures, such as those defined by the CORBA specification. CORBA is well-suited to conventional request/response applications, but not suited to real-time applications due to the lack of QoS features and performance optimizations. The paper shows the design and implementation of the high performance scheduling technique for the real time applications domain with CORBA systems. Four different algorithms are compared by using attributes of real time tasks constraints based on CORBA specification such as RMS, MLF, MUF and EDF.

  7. 3D Flash LIDAR Real-Time Embedded Processing Project

    National Aeronautics and Space Administration — 3D Flash LIDAR (3DFL) is ideal for determining real-time spacecraft trajectory, speed and orientation to the planet surface, as well as evaluating potential hazards...

  8. Real-Time Smart Tools for Processing Spectroscopy Data Project

    National Aeronautics and Space Administration — We propose novel and real-time smart software tools to process spectroscopy data. Material abundance or compositional maps will be generated for rover guidance,...

  9. NOAA Ship Oscar Dyson Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oscar Dyson Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  10. Analyzing Real-Time Systems: Theory and Tools

    Hune, Thomas Seidelin

    The main topic of this dissertation is the development and use of methods for formal reasoning about the correctness of real-time systems, in particular methods and tools to handle new classes of problems. In real-time systems the correctness of the system does not only depend on the order in which...... actions take place, but also the timing of the actions. The formal reasoning presented here is based on (extensions of) the model of timed automata and tools supporting this model, mainly UPPAAL. Real-time systems are often part of safety critical systems e.g. control systems for planes, trains......, or factories, though also everyday electronics as audio/video equipment and (mobile) phones are considered real-time systems. Often these systems are concurrent systems with a number of components interacting, and reasoning about such systems is notoriously difficult. However, since most of the systems...

  11. Real Time Control Software for Electromagnetic Formation Flight Project

    National Aeronautics and Space Administration — We propose the development of a maintainable and evolvable real-time control software system for Electromagnetic Formation Flight (EMFF). EMFF systems use...

  12. NOAA Ship Ronald Brown Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ronald Brown Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  13. NOAA Ship Fairweather Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Fairweather Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  14. A New Scheduling Algorithms For Real Time Tasks

    Yaashuwanth, C


    The main objective of this paper is to develop the two different ways in which round robin architecture is modified and made suitable to be implemented in real time and embedded systems. The scheduling algorithm plays a significant role in the design of real time embedded systems. Simple round robin architecture is not efficient to be implemented in embedded systems because of higher context switch rate, larger waiting time and larger response time. Missing of deadlines will degrade the system performance in soft real time systems. The main objective of this paper is to develop the scheduling algorithm which removes the drawbacks in simple round robin architecture. A comparison with round robin architecture to the proposed architectures has been made. It is observed that the proposed architectures solves the problems encountered in round robin architecture in soft real time by decreasing the number of context switches waiting time and response time thereby increasing the system throughput.

  15. Study on the Bus Real-time Dispatching Model

    YingZou; JianguoLi; JianhuaHuang; ZhenminTang


    The real-time dispatching model on bus system is studied in this article. Realtime dispatching can resume the planned schedule quickly, and then to ensure the reliability of the public transport service and to well raise the service quality.

  16. 3D Flash LIDAR Real-Time Embedded Processing Project

    National Aeronautics and Space Administration — Advanced Scientific Concepts, Inc. (ASC) is a small business, which has developed a compact, eye-safe 3D Flash LIDARTM Camera (FLC) well suited for real-time...

  17. Cluster Computing for Embedded/Real-Time Systems

    Katz, D.; Kepner, J.


    Embedded and real-time systems, like other computing systems, seek to maximize computing power for a given price, and thus can significantly benefit from the advancing capabilities of cluster computing.

  18. Games and Scenarios for Real-Time System Validation

    Li, Shuhao

    This thesis presents research on the validation of real-time embedded software systems in the context of model-based development. The thesis proposes scenario-based and game-theoretic approaches to system analysis, verification, synthesis and testing to address the challenges that arise from....... By linking our prototype translators with existing model checker Uppaal and game solver Uppaal-Tiga, we show that these methods contribute to the interaction correctness and timeliness of early system designs. The thesis also shows that testing a real-time reactive system can be viewed as playing a timed...... communicating real-time systems can be modeled and specified with LSC. By translating LSC to timed automata (TAs), we reduce scenario-based model consistency checking and property verification to CTL real-time model checking problems, and reduce scenario-based synthesis to a timed game solving problem...

  19. Specification and compilation of real-time stream processing applications

    Geuns, Stephanus Joannes


    This thesis is concerned with the specification, compilation and corresponding temporal analysis of real-time stream processing applications that are executed on embedded multiprocessor systems. An example of such applications are software defined radio applications. These applications typically hav

  20. Transformer real-time reliability model based on operating conditions

    HE Jian; CHENG Lin; SUN Yuan-zhang


    Operational reliability evaluation theory reflects real-time reliability level of power system. The component failure rate varies with operating conditions. The impact of real-time operating conditions such as ambient temperature and transformer MVA (megavolt-ampere) loading on transformer insulation life is studied in this paper. The formula of transformer failure rate based on the winding hottest-spot temperature (HST) is given. Thus the real-time reliability model of transformer based on operating conditions is presented. The work is illustrated using the 1979 IEEE Reliability Test System. The changes of operating conditions are simulated by using hourly load curve and temperature curve, so the curves of real-time reliability indices are obtained by using operational reliability evaluation.

  1. Optical Real-Time Space Radiation Monitor Project

    National Aeronautics and Space Administration — Real-time dosimetry is needed to provide immediate feedback, so astronauts can minimize their exposure to ionizing radiation during periods of high solar activity....

  2. Axo: Masking Delay Faults in Real-Time Control Systems

    Maaz, Mashood Mohiuddin; Saab, Wajeb; Bliudze, Simon; Le Boudec, Jean-Yves


    We consider real-time control systems that consist of a controller that computes and sends setpoints to be implemented in physical processes through process agents. We focus on systems that use commercial off-the-shelf hardware and software components. Setpoints of these systems have strict real-time constraints: Implementing a setpoint after its deadline, or not receiving setpoints within a deadline, can cause failure. In this paper, we address delay faults: faults that cause setpoints to vi...

  3. Migrating to a real-time distributed parallel simulator architecture

    Duvenhage, B


    Full Text Available DEVS. Ogata, et al. [7] tested the real-time performance of DIS and different versions of the RTI-NG HLA Run-Time Infrastructure (RTI). Their real-time vehicle model simulation within a 3D graphi- cal environment reached a frame rate ceiling... to mili- tary training simulation: A guide for discrete event sim- ulationists. In Proceedings of the 1998 Winter Simula- tion Conference, 1998. [7] Michihiko Ogata, Akira Higashide, Mike Cammarano, and Toshinao Takagi. Rti performance...

  4. Real time simulator with Ti floating point digital signal processor

    Razazian, K.; Bobis, J.P.; Dieckman, S.L.; Raptis, A.C.


    This paper describes the design and operation of a Real Time Simulator using Texas Instruments TMS320C30 digital signal processor. This system operates with two banks of memory which provide the input data to digital signal processor chip. This feature enables the TMS320C30 to be utilized in variety of applications for which external connections to acquire input data is not needed. In addition, some practical applications of this Real Time Simulator are discussed.

  5. Analysis and Synthesis of Distributed Real-Time Embedded Systems

    Pop, Paul; Eles, Petru; Peng, Zebo

    Embedded computer systems are now everywhere: from alarm clocks to PDAs, from mobile phones to cars, almost all the devices we use are controlled by embedded computers. An important class of embedded computer systems is that of hard real-time systems, which have to fulfill strict timing...... in important reductions of design costs. Analysis and Synthesis of Distributed Real-Time Embedded Systems will be of interest to advanced undergraduates, graduate students, researchers and designers involved in the field of embedded systems....

  6. Multi-Threat Real-Time Separating System


    This paper describes a multi-threat real-time separating system for broadband anti-radiation missile seeker.It presents a method, with a dual-port memory as comparer, to perform PF and PW hardware real-time separation and to determine the time-of-arrival (TOA) by use of sequential difference histogram (SDIF). The method has been applied to practice, which has achieved good results.

  7. Real Time Collision Detection Using Depth Texturing Spheres

    WANG Ji; ZHAI Zhengjun; CAI Xiaobin


    In this paper, we present a novel collision detection algorithm to real time detect the collisions of objects. We generate sphere textures of objects, and use programmable graphics hardware to mapping texture and check the depth of different objects to detect the collision. We have implemented the algorithm and compared it with CULLIDE. The result shows that our algorithm is more effective than CULLIDE and has fixed executive time to suit for real-time applications.

  8. Can Real-Time Data Also Be Climate Quality?

    Brewer, M.; Wentz, F. J.


    GMI, AMSR-2 and WindSat herald a new era of highly accurate and timely microwave data products. Traditionally, there has been a large divide between real-time and re-analysis data products. What if these completely separate processing systems could be merged? Through advanced modeling and physically based algorithms, Remote Sensing Systems (RSS) has narrowed the gap between real-time and research-quality. Satellite microwave ocean products have proven useful for a wide array of timely Earth science applications. Through cloud SST capabilities have enormously benefited tropical cyclone forecasting and day to day fisheries management, to name a few. Oceanic wind vectors enhance operational safety of shipping and recreational boating. Atmospheric rivers are of import to many human endeavors, as are cloud cover and knowledge of precipitation events. Some activities benefit from both climate and real-time operational data used in conjunction. RSS has been consistently improving microwave Earth Science Data Records (ESDRs) for several decades, while making near real-time data publicly available for semi-operational use. These data streams have often been produced in 2 stages: near real-time, followed by research quality final files. Over the years, we have seen this time delay shrink from months or weeks to mere hours. As well, we have seen the quality of near real-time data improve to the point where the distinction starts to blur. We continue to work towards better and faster RFI filtering, adaptive algorithms and improved real-time validation statistics for earlier detection of problems. Can it be possible to produce climate quality data in real-time, and what would the advantages be? We will try to answer these questions…

  9. Collaborative Real-time Digital Reference Services in Academic Libraries

    Shiao-Feng Su


    Full Text Available The real-time digital reference service is valued by most academic librarians in United States. To make the collaborative real-time digital reference service viable in academic library service, the libraries need to understand the information seeking behavior of potential users and to train the staff well. The participating libraries also need to coordinate the following issues in advance: quality control, question routing, network standards, cultural and political sensitivities, communication, copyright, and marketing. [Article content in Chinese

  10. Implementation of real-time duplex synthetic aperture ultrasonography

    Hemmsen, Martin Christian; Larsen, Lee; Kjeldsen, Thomas;


    This paper presents a real-time duplex synthetic aperture imaging system, implemented on a commercially available tablet. This includes real-time wireless reception of ultrasound signals and GPU processing for B-mode and Color Flow Imaging (CFM). The objective of the work is to investigate the im...... and that the required bandwidth between the probe and processing unit is within the current Wi-Fi standards....

  11. Real-Time Connect 4 Game Using Artificial Intelligence

    Ahmad M. Sarhan


    Full Text Available Problem statement: The study presented a design that converted connect 4 game into a real-time game by incorporating time restraints. Approach: The design used Artificial Intelligence (AI in implementing the connect 4 game. The AI for this game was based on influence mapping. Results: A waterfall-based AI software was developed for a Connect 4 game. Conclusion: A real time connect 4 game was successfully designed and implanted with GUI using C++ programming language.

  12. Near real-time stereo matching using geodesic diffusion.

    De-Maeztu, Leonardo; Villanueva, Arantxa; Cabeza, Rafael


    Adaptive-weight algorithms currently represent the state of the art in local stereo matching. However, due to their computational requirements, these types of solutions are not suitable for real-time implementation. Here, we present a novel aggregation method inspired by the anisotropic diffusion technique used in image filtering. The proposed aggregation algorithm produces results similar to adaptive-weight solutions while reducing the computational requirements. Moreover, near real-time performance is demonstrated with a GPU implementation of the algorithm.

  13. Design a Fault Tolerance for Real Time Distributed System

    Ban M. Khammas


    This paper designed a fault tolerance for soft real time distributed system (FTRTDS). This system is designed to be independently on specific mechanisms and facilities of the underlying real time distributed system. It is designed to be distributed on all the computers in the distributed system and controlled by a central unit.Besides gathering information about a target program spontaneously, it provides information about the target operating system and the target hardware in order to diagno...


    刘均; 李人厚; 郑庆华


    Aiming at issues on multimedia communication in synchronous real-time teleteaching (SRT) systems over IP network, a 4-tuple structural mode of multimedia communication is proposed in the paper, and an SRT-oriented distributed MCU model is built according to the mode. Moreover, the mechanism of multicast communication across subnets is discussed. The distributed MCU model has been applied successfully in our interactive synchronous real-time telesteaching system RealClass and has shown good extendibility in operation.

  15. The Dynamic Checking of Complex Real Time System

    YU Chao; HUANG Benwen; WU Guoqing


    The paper presents an dynamic execution model of complex real-time software based on requirement description model RTRSM, and then propose a checking method based on configuration covering and its corresponding algorithm. This checking method can check the execution situations between parallel elements in a dynamic execution step of real-time software systems. It also can check all the states and transitions which assure the completeness of checking. In the end, related theorem is proofed.

  16. Real-time radiography at the NECTAR facility

    Buecherl, T., E-mail: [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM), Walther-Meissner-Str. 3, 85748 Garching (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM), Walther-Meissner-Str. 3, 85748 Garching (Germany)


    A feasibility study has shown that real-time radiography using fission neutrons is possible at the NECTAR facility, when using an improved detection system for fast variations (Buecherl et al., 2009 ). Continuing this study, real-time measurements of slowly varying processes like the water uptake in medium sized trunks (diameter about 12 cm) and of slow periodic processes (e.g. a slowly rotating iron disk) are investigated successfully using the existing detection system.

  17. A Remote Real-Time Monitoring System for Power Quality

    黄治清; 贺建闽


    An introduction is made to the composition, design method and engineering application of a remote real-time monitoring system of power quality in substations based on internet. With virtual instrument and network technique adopted, this system is characterized by good real-time property, high reliability, plentiful functions, and so on. It also can be used to monitor the load of a substation, such as electric locomotives.

  18. Streaming Surface Reconstruction from Real Time 3D Measurements

    Bodenmüller, Tim


    In this thesis, a robust method for fast surface reconstruction from real time 3D point streams is presented. It is designed for the integration in a fast visual feedback system that supports a user while manually 3D scanning objects. The method iteratively generates a dense and homogeneous triangular mesh by inserting sample points from the real time data stream and refining the surface model locally. A spatial data structure ensures a fast access to growing point sets and continuously updat...

  19. A real time method for surface cleanliness measurement

    Bilmes, Gabriel Mario; Orzi, Daniel Jesús Omar; Martínez , Oscar E.; Lencina, Alberto


    The measurement of surface cleanliness is a signifi cant problem in many industrial and technological processes. Existing methods are based on laboratory procedures, that are not performed in real time, can not be automated, and usually are restricted to a small portion of the sample. In this study we describe a new method for real time measurement of the amount of surface dirt or contamination deposited on a surface. It relies on the ablation of the surface dirt film by means of a ...

  20. Search-Space Characterization for Real-time Heuristic Search

    Huntley, Daniel; Bulitko, Vadim


    Recent real-time heuristic search algorithms have demonstrated outstanding performance in video-game pathfinding. However, their applications have been thus far limited to that domain. We proceed with the aim of facilitating wider applications of real-time search by fostering a greater understanding of the performance of recent algorithms. We first introduce eight algorithm-independent complexity measures for search spaces and correlate their values with algorithm performance. The complexity ...

  1. High speed, real-time, camera bandwidth converter

    Bower, Dan E; Bloom, David A; Curry, James R


    Image data from a CMOS sensor with 10 bit resolution is reformatted in real time to allow the data to stream through communications equipment that is designed to transport data with 8 bit resolution. The incoming image data has 10 bit resolution. The communication equipment can transport image data with 8 bit resolution. Image data with 10 bit resolution is transmitted in real-time, without a frame delay, through the communication equipment by reformatting the image data.

  2. Real-time simulation of dissipation-driven quantum systems

    Banerjee, Debasish; Jiang, Fu-Jiun; Kon, Mark; Wiese, Uwe-Jens


    We set up a real-time path integral to study the evolution of quantum systems driven in real-time completely by the coupling of the system to the environment. For specifically chosen interactions, this can be interpreted as measurements being performed on the system. For a spin-1/2 system, in particular, when the measurement results are averaged over, the resulting sign problem completely disappears, and the system can be simulated with an efficient cluster algorithm.

  3. Classification of myocardial infarction

    Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne Elisabeth


    The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...... and supply of oxygen in the myocardium. However, no specific criteria for type 2 myocardial infarction have been established....

  4. Real-time estimation of dynamic functional connectivity networks.

    Monti, Ricardo Pio; Lorenz, Romy; Braga, Rodrigo M; Anagnostopoulos, Christoforos; Leech, Robert; Montana, Giovanni


    Two novel and exciting avenues of neuroscientific research involve the study of task-driven dynamic reconfigurations of functional connectivity networks and the study of functional connectivity in real-time. While the former is a well-established field within neuroscience and has received considerable attention in recent years, the latter remains in its infancy. To date, the vast majority of real-time fMRI studies have focused on a single brain region at a time. This is due in part to the many challenges faced when estimating dynamic functional connectivity networks in real-time. In this work, we propose a novel methodology with which to accurately track changes in time-varying functional connectivity networks in real-time. The proposed method is shown to perform competitively when compared to state-of-the-art offline algorithms using both synthetic as well as real-time fMRI data. The proposed method is applied to motor task data from the Human Connectome Project as well as to data obtained from a visuospatial attention task. We demonstrate that the algorithm is able to accurately estimate task-related changes in network structure in real-time. Hum Brain Mapp 38:202-220, 2017. © 2016 Wiley Periodicals, Inc.

  5. Real-time feedback from iterative electronic structure calculations.

    Vaucher, Alain C; Haag, Moritz P; Reiher, Markus


    Real-time feedback from iterative electronic structure calculations requires to mediate between the inherently unpredictable execution times of the iterative algorithm used and the necessity to provide data in fixed and short time intervals for real-time rendering. We introduce the concept of a mediator as a component able to deal with infrequent and unpredictable reference data to generate reliable feedback. In the context of real-time quantum chemistry, the mediator takes the form of a surrogate potential that has the same local shape as the first-principles potential and can be evaluated efficiently to deliver atomic forces as real-time feedback. The surrogate potential is updated continuously by electronic structure calculations and guarantees to provide a reliable response to the operator for any molecular structure. To demonstrate the application of iterative electronic structure methods in real-time reactivity exploration, we implement self-consistent semiempirical methods as the data source and apply the surrogate-potential mediator to deliver reliable real-time feedback.

  6. Evaluation of Real-Time Services in Mobile WIMAX

    Z. Naumoski


    Full Text Available In this paper we provide a performance analysis for real-time services with a limited bandwidth in a single-cell Mobile WiMAX network. We analyze the most critical performance parameters for real-time services, such as voice over IP. Since the throughput is a given constraint for a real-time service, the focus is on delay and jitter introduced by the Mobile WiMAX technology. We have used different user velocities, including nomadic users as well as mobile users. The main contribution of this paper is that we have shown that Mobile WiMAX can be efficiently used for real-time services with applied admission control and priority over non-real-time traffic, because it is adding a very small portion to the delay budget for the real-time service, as well as it keeps the jitter far below the end-to-end jitter threshold for telephony in a Mobile WiMAX network.

  7. Mechatronic modeling of real-time wheel-rail contact

    Bosso, Nicola; Gugliotta, Antonio; Somà, Aurelio


    Real-time simulations of the behaviour of a rail vehicle require realistic solutions of the wheel-rail contact problem which can work in a real-time mode. Examples of such solutions for the online mode have been well known and are implemented within standard and commercial tools for the simulation codes for rail vehicle dynamics. This book is the result of the research activities carried out by the Railway Technology Lab of the Department of Mechanical and Aerospace Engineering at Politecnico di Torino. This book presents work on the project for the development of a real-time wheel-rail contact model and provides the simulation results obtained with dSpace real-time hardware. Besides this, the implementation of the contact model for the development of a real-time model for the complex mechatronic system of a scaled test rig is presented in this book and may be useful for the further validation of the real-time contact model with experiments on a full scale test rig.

  8. Real-time Java for on-board systems

    Cechticky, V.; Pasetti, A.


    The Java language has several attractive features but cannot at present be used in on-board systems primarily because it lacks support for hard real-time operation. This shortcoming is in being addressed: some suppliers are already providing implementations of Java that are RT-compliant; Sun Microsystem has approved a formal specification for a real-time extension of the language; and an independent consortium is working on an alternative specification for real-time Java. It is therefore expected that, within a year or so, standardized commercial implementations of real-time Java will be on the market. Availability of real-time implementations now opens the way to its use on-board. Within this context, this paper has two objectives. Firstly, it discusses the suitability of Java for on-board applications. Secondly, it reports the results of an ESA study to port a software framework for on-board control systems to a commercial real-time version of Java.

  9. Real-time extended-depth DIC microscopy

    Beckers, Ingeborg E.; Cormack, Robert H.; Cogswell, Carol J.


    Real-time visualization of live-cell dynamic processes has been realized in differential interference contrast (DIC) microscopy, with an extended-depth-of-focus (EDF) increase of about one order of magnitude. In addition, the diffraction-limited lateral resolution of the microscope is preserved. Experimentally, a custom-designed waveplate inserted in the optical path of a microscope causes feature information, from within the entire 3D specimen volume, to be uniformly encoded into a single CCD image in a way that, after processing, defocus blur artifacts are removed. The result is that extended-depth feature information can be visualized at video rates during live-cell dynamics investigations because there is no longer the need to acquire multi-focus image stacks at each time point. Retrieving the encoded extended-depth information requires specialized digital image processing techniques. This work concentrates on digital filter design for the reconstruction of the waveplate-encoded images. As a measure of filter quality, the signal-to-noise ratio (SNR), the modulation transfer function and the least mean square values are evaluated. Obtaining a high SNR and a lateral resolution comparable to those in conventional single-focus-plane microscopy images at the same time is a challenging goal in EDF microscopy. Filters are created in the frequency domain on the basis of the measured waveplate-encoded point spread functions. Results show that it is possible to produce video-rate, extended-depth-offocus images that have low noise levels and diffraction-limited resolution. This is illustrated by movies of fluorescent beads and of cytoplasmic streaming in live stamen hair cells from the spiderwort plant, Tradescantia, using extendeddepth DIC microscopy.

  10. First results of the EGSIEM Near Real-Time Service

    Kvas, Andreas; Gruber, Christian; Gouweleeuw, Ben; Chen, Qiang; Poropat, Lea; Flechtner, Frank; Mayer-Gürr, Torsten; Güntner, Andreas


    To enable the use of GRACE and GRACE-FO earth observation data for rapid monitoring applications, the Horizon2020 funded EGSIEM (European Gravity Service for Improved Emergency Management) project has established a demonstrator for a near real-time (NRT) gravity field service. The service aims to increase the temporal resolution of mass transport products from one month to one day and to reduce the latency from currently two months to five days. This allows the monitoring of hydrological extreme events as they occur, in contrast to a 'confirmation after occurrence' as is the situation today. The service will be jointly run by GFZ (German Research Centre for Geosciences) and Graz University of Technology, with each analysis center providing an independent solution. On-line validation will be performed by the University of Luxembourg using GNSS loading. A six-month long operational test run of the service starting in April 2017 is planned, in case GRACE Quick-Look data (provided by JPL) is still available. Within this time period, daily gravity field solutions serve as input to the EGSIEM Hydrological Service, which derives flood and drought indicators to be used within DLR's Center for Satellite Based Crisis Information and the Global Flood Awareness System (GloFAS). This contribution highlights the current status of the NRT service and the results of the preparation phase. The performance of the NRT mass transport products will be shown by comparison with independent GNSS loading and ocean bottom pressure data as well as as catchment aggregated values for hydrological extreme events.

  11. Myocardial Extracellular Volume Fraction with Dual-Energy Equilibrium Contrast-enhanced Cardiac CT in Nonischemic Cardiomyopathy: A Prospective Comparison with Cardiac MR Imaging.

    Lee, Hye-Jeong; Im, Dong Jin; Youn, Jong-Chan; Chang, Suyon; Suh, Young Joo; Hong, Yoo Jin; Kim, Young Jin; Hur, Jin; Choi, Byoung Wook


    Purpose To evaluate the feasibility of equilibrium contrast material-enhanced dual-energy cardiac computed tomography (CT) to determine extracellular volume fraction (ECV) in nonischemic cardiomyopathy (CMP) compared with magnetic resonance (MR) imaging. Materials and Methods This study was approved by the institutional review board; informed consent was obtained. Seven healthy subjects and 23 patients (six with hypertrophic CMP, nine with dilated CMP, four with amyloidosis, and four with sarcoidosis) (mean age ± standard deviation, 57.33 years ± 14.82; 19 male participants [63.3%]) were prospectively enrolled. Twelve minutes after contrast material injection (1.8 mL/kg at 3 mL/sec), dual-energy cardiac CT was performed. ECV was measured by two observers independently. Hematocrit levels were compared between healthy subjects and patients with the Mann-Whitney U test. In per-subject analysis, interobserver agreement for CT was assessed with the intraclass correlation coefficient (ICC), and intertest agreement between MR imaging and CT was assessed with Bland-Altman analysis. In per-segment analysis, Student t tests in the linear mixed model were used to compare ECV on CT images between healthy subjects and patients. Results Hematocrit level was 43.44% ± 1.80 for healthy subjects and 41.23% ± 5.61 for patients with MR imaging (P = .16) and 43.50% ± 1.92 for healthy subjects and 41.35% ± 5.92 for patients with CT (P = .15). For observer 1 in per-subject analysis, ECV was 34.18% ± 8.98 for MR imaging and 34.48% ± 8.97 for CT. For observer 2, myocardial ECV was 34.42% ± 9.03 for MR imaging and 33.98% ± 9.05 for CT. Interobserver agreement for ECV at CT was excellent (ICC = 0.987). Bland-Altman analysis between MR imaging and CT showed a small bias (-0.06%), with 95% limits of agreement of -1.19 and 1.79. Compared with healthy subjects, patients with hypertrophic CMP, dilated CMP, amyloidosis, and sarcoidosis had significantly higher myocardial ECV at dual

  12. Low-dose dynamic myocardial perfusion CT image reconstruction using pre-contrast normal-dose CT scan induced structure tensor total variation regularization

    Gong, Changfei; Han, Ce; Gan, Guanghui; Deng, Zhenxiang; Zhou, Yongqiang; Yi, Jinling; Zheng, Xiaomin; Xie, Congying; Jin, Xiance


    Dynamic myocardial perfusion CT (DMP-CT) imaging provides quantitative functional information for diagnosis and risk stratification of coronary artery disease by calculating myocardial perfusion hemodynamic parameter (MPHP) maps. However, the level of radiation delivered by dynamic sequential scan protocol can be potentially high. The purpose of this work is to develop a pre-contrast normal-dose scan induced structure tensor total variation regularization based on the penalized weighted least-squares (PWLS) criteria to improve the image quality of DMP-CT with a low-mAs CT acquisition. For simplicity, the present approach was termed as ‘PWLS-ndiSTV’. Specifically, the ndiSTV regularization takes into account the spatial-temporal structure information of DMP-CT data and further exploits the higher order derivatives of the objective images to enhance denoising performance. Subsequently, an effective optimization algorithm based on the split-Bregman approach was adopted to minimize the associative objective function. Evaluations with modified dynamic XCAT phantom and preclinical porcine datasets have demonstrated that the proposed PWLS-ndiSTV approach can achieve promising gains over other existing approaches in terms of noise-induced artifacts mitigation, edge details preservation, and accurate MPHP maps calculation.

  13. Real Time Fire Reconnaissance Satellite Monitoring System Failure Model

    Nino Prieto, Omar Ariosto; Colmenares Guillen, Luis Enrique


    In this paper the Real Time Fire Reconnaissance Satellite Monitoring System is presented. This architecture is a legacy of the Detection System for Real-Time Physical Variables which is undergoing a patent process in Mexico. The methodologies for this design are the Structured Analysis for Real Time (SA- RT) [8], and the software is carried out by LACATRE (Langage d'aide à la Conception d'Application multitâche Temps Réel) [9,10] Real Time formal language. The system failures model is analyzed and the proposal is based on the formal language for the design of critical systems and Risk Assessment; AltaRica. This formal architecture uses satellites as input sensors and it was adapted from the original model which is a design pattern for physical variation detection in Real Time. The original design, whose task is to monitor events such as natural disasters and health related applications, or actual sickness monitoring and prevention, as the Real Time Diabetes Monitoring System, among others. Some related work has been presented on the Mexican Space Agency (AEM) Creation and Consultation Forums (2010-2011), and throughout the International Mexican Aerospace Science and Technology Society (SOMECYTA) international congress held in San Luis Potosí, México (2012). This Architecture will allow a Real Time Fire Satellite Monitoring, which will reduce the damage and danger caused by fires which consumes the forests and tropical forests of Mexico. This new proposal, permits having a new system that impacts on disaster prevention, by combining national and international technologies and cooperation for the benefit of humankind.

  14. Geomagnetic Observatory Data for Real-Time Applications

    Love, J. J.; Finn, C. A.; Rigler, E. J.; Kelbert, A.; Bedrosian, P.


    The global network of magnetic observatories represents a unique collective asset for the scientific community. Historically, magnetic observatories have supported global magnetic-field mapping projects and fundamental research of the Earth's interior and surrounding space environment. More recently, real-time data streams from magnetic observatories have become an important contributor to multi-sensor, operational monitoring of evolving space weather conditions, especially during magnetic storms. In this context, the U.S. Geological Survey (1) provides real-time observatory data to allied space weather monitoring projects, including those of NOAA, the U.S. Air Force, NASA, several international agencies, and private industry, (2) collaborates with Schlumberger to provide real-time geomagnetic data needed for directional drilling for oil and gas in Alaska, (3) develops products for real-time evaluation of hazards for the electric-power grid industry that are associated with the storm-time induction of geoelectric fields in the Earth's conducting lithosphere. In order to implement strategic priorities established by the USGS Natural Hazards Mission Area and the National Science and Technology Council, and with a focus on developing new real-time products, the USGS is (1) leveraging data management protocols already developed by the USGS Earthquake Program, (2) developing algorithms for mapping geomagnetic activity, a collaboration with NASA and NOAA, (3) supporting magnetotelluric surveys and developing Earth conductivity models, a collaboration with Oregon State University and the NSF's EarthScope Program, (4) studying the use of geomagnetic activity maps and Earth conductivity models for real-time estimation of geoelectric fields, (5) initiating geoelectric monitoring at several observatories, (6) validating real-time estimation algorithms against historical geomagnetic and geoelectric data. The success of these long-term projects is subject to funding constraints

  15. Comparison of infarct size changes with delayed contrast-enhanced magnetic resonance imaging and electrocardiogram QRS scoring during the 6 months after acutely reperfused myocardial infarction

    Bang, L.E.; Ripa, R.S.; Grande, P.


    that has infarcted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size. AIM: The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates......INTRODUCTION: Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium...... of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases. METHODS: In 31 patients (26 men, age 56 +/- 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were...

  16. Real-Time Tropospheric Delay Estimation using IGS Products

    Stürze, Andrea; Liu, Sha; Söhne, Wolfgang


    The Federal Agency for Cartography and Geodesy (BKG) routinely provides zenith tropospheric delay (ZTD) parameter for the assimilation in numerical weather models since more than 10 years. Up to now the results flowing into the EUREF Permanent Network (EPN) or E-GVAP (EUMETNET EIG GNSS water vapour programme) analysis are based on batch processing of GPS+GLONASS observations in differential network mode. For the recently started COST Action ES1206 about "Advanced Global Navigation Satellite Systems tropospheric products for monitoring severe weather events and climate" (GNSS4SWEC), however, rapid updates in the analysis of the atmospheric state for nowcasting applications require changing the processing strategy towards real-time. In the RTCM SC104 (Radio Technical Commission for Maritime Services, Special Committee 104) a format combining the advantages of Precise Point Positioning (PPP) and Real-Time Kinematic (RTK) is under development. The so-called State Space Representation approach is defining corrections, which will be transferred in real-time to the user e.g. via NTRIP (Network Transport of RTCM via Internet Protocol). Meanwhile messages for precise orbits, satellite clocks and code biases compatible to the basic PPP mode using IGS products are defined. Consequently, the IGS Real-Time Service (RTS) was launched in 2013 in order to extend the well-known precise orbit and clock products by a real-time component. Further messages e.g. with respect to ionosphere or phase biases are foreseen. Depending on the level of refinement, so different accuracies up to the RTK level shall be reachable. In co-operation of BKG and the Technical University of Darmstadt the real-time software GEMon (GREF EUREF Monitoring) is under development. GEMon is able to process GPS and GLONASS observation and RTS product data streams in PPP mode. Furthermore, several state-of-the-art troposphere models, for example based on numerical weather prediction data, are implemented. Hence, it

  17. The improved broadband Real-Time Seismic Network in Romania

    Neagoe, C.; Ionescu, C.


    Starting with 2002 the National Institute for Earth Physics (NIEP) has developed its real-time digital seismic network. This network consists of 96 seismic stations of which 48 broad band and short period stations and two seismic arrays are transmitted in real-time. The real time seismic stations are equipped with Quanterra Q330 and K2 digitizers, broadband seismometers (STS2, CMG40T, CMG 3ESP, CMG3T) and strong motions sensors Kinemetrics episensors (+/- 2g). SeedLink and AntelopeTM (installed on MARMOT) program packages are used for real-time (RT) data acquisition and exchange. The communication from digital seismic stations to the National Data Center in Bucharest is assured by 5 providers (GPRS, VPN, satellite communication, radio lease line and internet), which will assure the back-up communications lines. The processing centre runs BRTT's AntelopeTM 4.10 data acquisition and processing software on 2 workstations for real-time processing and post processing. The Antelope Real-Time System is also providing automatic event detection, arrival picking, event location and magnitude calculation. It provides graphical display and reporting within near-real-time after a local or regional event occurred. Also at the data center was implemented a system to collect macroseismic information using the internet on which macro seismic intensity maps are generated. In the near future at the data center will be install Seiscomp 3 data acquisition processing software on a workstation. The software will run in parallel with Antelope software as a back-up. The present network will be expanded in the near future. In the first half of 2009 NIEP will install 8 additional broad band stations in Romanian territory, which also will be transmitted to the data center in real time. The Romanian Seismic Network is permanently exchanging real -time waveform data with IRIS, ORFEUS and different European countries through internet. In Romania, magnitude and location of an earthquake are now

  18. Lightweight distributed computing for intraoperative real-time image guidance

    Suwelack, Stefan; Katic, Darko; Wagner, Simon; Spengler, Patrick; Bodenstedt, Sebastian; Röhl, Sebastian; Dillmann, Rüdiger; Speidel, Stefanie


    In order to provide real-time intraoperative guidance, computer assisted surgery (CAS) systems often rely on computationally expensive algorithms. The real-time constraint is especially challenging if several components such as intraoperative image processing, soft tissue registration or context aware visualization are combined in a single system. In this paper, we present a lightweight approach to distribute the workload over several workstations based on the OpenIGTLink protocol. We use XML-based message passing for remote procedure calls and native types for transferring data such as images, meshes or point coordinates. Two different, but typical scenarios are considered in order to evaluate the performance of the new system. First, we analyze a real-time soft tissue registration algorithm based on a finite element (FE) model. Here, we use the proposed approach to distribute the computational workload between a primary workstation that handles sensor data processing and visualization and a dedicated workstation that runs the real-time FE algorithm. We show that the additional overhead that is introduced by the technique is small compared to the total execution time. Furthermore, the approach is used to speed up a context aware augmented reality based navigation system for dental implant surgery. In this scenario, the additional delay for running the computationally expensive reasoning server on a separate workstation is less than a millisecond. The results show that the presented approach is a promising strategy to speed up real-time CAS systems.

  19. Spatio-temporal modeling for real-time ozone forecasting.

    Paci, Lucia; Gelfand, Alan E; Holland, David M


    The accurate assessment of exposure to ambient ozone concentrations is important for informing the public and pollution monitoring agencies about ozone levels that may lead to adverse health effects. High-resolution air quality information can offer significant health benefits by leading to improved environmental decisions. A practical challenge facing the U.S. Environmental Protection Agency (USEPA) is to provide real-time forecasting of current 8-hour average ozone exposure over the entire conterminous United States. Such real-time forecasting is now provided as spatial forecast maps of current 8-hour average ozone defined as the average of the previous four hours, current hour, and predictions for the next three hours. Current 8-hour average patterns are updated hourly throughout the day on the EPA-AIRNow web site. The contribution here is to show how we can substantially improve upon current real-time forecasting systems. To enable such forecasting, we introduce a downscaler fusion model based on first differences of real-time monitoring data and numerical model output. The model has a flexible coefficient structure and uses an efficient computational strategy to fit model parameters. Our hybrid computational strategy blends continuous background updated model fitting with real-time predictions. Model validation analyses show that we are achieving very accurate and precise ozone forecasts.

  20. Real-time simulation of thermal shadows with EMIT

    Klein, Andreas; Oberhofer, Stefan; Schätz, Peter; Nischwitz, Alfred; Obermeier, Paul


    Modern missile systems use infrared imaging for tracking or target detection algorithms. The development and validation processes of these missile systems need high fidelity simulations capable of stimulating the sensors in real-time with infrared image sequences from a synthetic 3D environment. The Extensible Multispectral Image Generation Toolset (EMIT) is a modular software library developed at MBDA Germany for the generation of physics-based infrared images in real-time. EMIT is able to render radiance images in full 32-bit floating point precision using state of the art computer graphics cards and advanced shader programs. An important functionality of an infrared image generation toolset is the simulation of thermal shadows as these may cause matching errors in tracking algorithms. However, for real-time simulations, such as hardware in the loop simulations (HWIL) of infrared seekers, thermal shadows are often neglected or precomputed as they require a thermal balance calculation in four-dimensions (3D geometry in one-dimensional time up to several hours in the past). In this paper we will show the novel real-time thermal simulation of EMIT. Our thermal simulation is capable of simulating thermal effects in real-time environments, such as thermal shadows resulting from the occlusion of direct and indirect irradiance. We conclude our paper with the practical use of EMIT in a missile HWIL simulation.

  1. Real-time Simulation of Turboprop Engine Control System

    Sheng, Hanlin; Zhang, Tianhong; Zhang, Yi


    On account of the complexity of turboprop engine control system, real-time simulation is the technology, under the prerequisite of maintaining real-time, to effectively reduce development cost, shorten development cycle and avert testing risks. The paper takes RT-LAB as a platform and studies the real-time digital simulation of turboprop engine control system. The architecture, work principles and external interfaces of RT-LAB real-time simulation platform are introduced firstly. Then based on a turboprop engine model, the control laws of propeller control loop and fuel control loop are studied. From that and on the basis of Matlab/Simulink, an integrated controller is designed which can realize the entire process control of the engine from start-up to maximum power till stop. At the end, on the basis of RT-LAB platform, the real-time digital simulation of the designed control system is studied, different regulating plans are tried and more ideal control effects have been obtained.

  2. Basic technology development of a real-time graphic simulator

    Jeon, Jae Wook; Hong, Soon Hyuk; Lee, Kyung Hoon; Lee, Sang-Hyun; Lee, Hee Sub [Sungkyunkwan Univ., Seoul (Korea)


    In this research, we developed the basic technology of a Real-time graphic simulator for remote monitoring in hostile environment, the Spent Fuel Disassembling facility. The use of a real-time graphic simulator is very useful for building virtual workcell and simulating the virtual devices to preview the behavior of real devices in order to reduce the error in design step of devices and to evaluate and optimize the work processes. And also, it can be used to provide the visualization of operation information from working devices to ensure the reliable monitoring in the teleoperation system. Thus, the development of basic technology related to these is needed. In this system, because the Spent Fuel Disassembling facility should be managed in remote environment due to its characteristics, the transmission of operational information through the network should be used. And for real-time monitoring, the real-time visualization of operational information from real system should be available. Therefore, we defined the efficient message protocol format for real-time transmission of operational information to visualize these in the 3D graphic simulator. 14 refs., 44 figs., 2 tabs. (Author)

  3. Development of automated system for real-time LIBS analysis

    Mazalan, Elham; Ali, Jalil; Tufail, Kashif; Haider, Zuhaib


    Recent developments in Laser Induced Breakdown Spectroscopy (LIBS) instrumentation allow the acquisition of several spectra in a second. The dataset from a typical LIBS experiment can consist of a few thousands of spectra. To extract the useful information from that dataset is painstaking effort and time consuming process. Most of the currently available softwares for spectral data analysis are expensive and used for offline data analysis. LabVIEW software compatible with spectrometer (in this case Ocean Optics Maya pro spectrometer), can be used to for data acquisition and real time analysis. In the present work, a LabVIEW based automated system for real-time LIBS analysis integrated with spectrometer device is developed. This system is capable of performing real time analysis based on as-acquired LIBS spectra. Here, we have demonstrated the LIBS data acquisition and real time calculations of plasma temperature and electron density. Data plots and variations in spectral intensity in response to laser energy were observed on LabVIEW monitor interface. Routine laboratory samples of brass and calcine bone were utilized in this experiment. Developed program has shown impressive performance in real time data acquisition and analysis.

  4. Autonomous and 3D real-time multi-beam manipulation in a microfluidic environment

    Perch-Nielsen, I.; Rodrigo, P.J.; Alonzo, C.A.; Glückstad, J


    The Generalized Phase Contrast (GPC) method of optical 3D manipulation has previously been used for controlled spatial manipulation of live biological specimen in real-time. These biological experiments were carried out over a time-span of several hours while an operator intermittently optimized the optical system. Here we present GPC-based optical micromanipulation in a microfluidic system where trapping experiments are computer-automated and thereby capable of running with only limited supe...

  5. Relationship between myocardial extracellular space expansion estimated with post-contrast T1 mapping MRI and left ventricular remodeling and neurohormonal activation in patients with dilated cardiomyopathy

    Yoon, Ji Hyun; Son, Jung Woo; Chung, Hye Moon [Cardiology Division, Dept. of Internal Medicine, Yonsei University College of Medicine, Seoul (Korea, Republic of); and others


    Post-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM). Fifty-nine patients with DCM (mean age, 55 ± 15 years; 41 males and 18 females) who underwent both 1.5T magnetic resonance imaging and echocardiography were enrolled. The post-contrast 10-minute T1 value was generated from inversion time scout images obtained using the Look-Locker inversion recovery sequence and a curve-fitting algorithm. The T1 sample volume was obtained from three interventricular septal points, and the mean T1 value was used for analysis. The N-Terminal pro-B-type natriuretic peptide (NT-proBNP) level was measured in 40 patients. The mean LV ejection fraction was 24 ± 9% and the post-T1 value was 254.5 ± 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s'), peak late diastolic velocity of the mitral annulus (a'), the diastolic elastance index (Ed, [E/e']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (β = -0.351, p = 0.016) and the LV mass/volume ratio (β = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (β = -0.339, p = 0.017). Post-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM.

  6. A constrained ICA approach for real-time cardiac artifact rejection in magnetoencephalography.

    Breuer, Lukas; Dammers, Jürgen; Roberts, Timothy P L; Shah, N Jon


    Recently, magnetoencephalography (MEG)-based real-time brain computing interfaces (BCI) have been developed to enable novel and promising methods of neuroscience research and therapy. Artifact rejection prior to source localization largely enhances the localization accuracy. However, many BCI approaches neglect real-time artifact removal due to its time consuming processing. With cardiac artifact rejection for real-time analysis (CARTA), we introduce a novel algorithm capable of real-time cardiac artifact (CA) rejection. The method is based on constrained independent component analysis (ICA), where a priori information of the underlying source signal is used to optimize and accelerate signal decomposition. In CARTA, this is performed by estimating the subject's individual density distribution of the cardiac activity, which leads to a subject-specific signal decomposition algorithm. We show that the new method is capable of effectively reducing CAs within one iteration and a time delay of 1 ms. In contrast, Infomax and Extended Infomax ICA converged not until seven iterations, while FastICA needs at least ten iterations. CARTA was tested and applied to data from three different but most common MEG systems (4-D-Neuroimaging, VSM MedTech Inc., and Elekta Neuromag). Therefore, the new method contributes to reliable signal analysis utilizing BCI approaches.

  7. Explaining How to Play Real-Time Strategy Games

    Metoyer, Ronald; Stumpf, Simone; Neumann, Christoph; Dodge, Jonathan; Cao, Jill; Schnabel, Aaron

    Real-time strategy games share many aspects with real situations in domains such as battle planning, air traffic control, and emergency response team management which makes them appealing test-beds for Artificial Intelligence (AI) and machine learning. End user annotations could help to provide supplemental information for learning algorithms, especially when training data is sparse. This paper presents a formative study to uncover how experienced users explain game play in real-time strategy games. We report the results of our analysis of explanations and discuss their characteristics that could support the design of systems for use by experienced real-time strategy game users in specifying or annotating strategy-oriented behavior.

  8. Real-time structured light intraoral 3D measurement pipeline

    Gheorghe, Radu; Tchouprakov, Andrei; Sokolov, Roman


    Computer aided design and manufacturing (CAD/CAM) is increasingly becoming a standard feature and service provided to patients in dentist offices and denture manufacturing laboratories. Although the quality of the tools and data has slowly improved in the last years, due to various surface measurement challenges, practical, accurate, invivo, real-time 3D high quality data acquisition and processing still needs improving. Advances in GPU computational power have allowed for achieving near real-time 3D intraoral in-vivo scanning of patient's teeth. We explore in this paper, from a real-time perspective, a hardware-software-GPU solution that addresses all the requirements mentioned before. Moreover we exemplify and quantify the hard and soft deadlines required by such a system and illustrate how they are supported in our implementation.

  9. Real time capable infrared thermography for ASDEX Upgrade

    Sieglin, B., E-mail:; Faitsch, M.; Herrmann, A.; Brucker, B.; Eich, T.; Kammerloher, L.; Martinov, S. [Max-Planck Institute for Plasma Physics, Boltzmannstr. 2, D-85748 Garching (Germany)


    Infrared (IR) thermography is widely used in fusion research to study power exhaust and incident heat load onto the plasma facing components. Due to the short pulse duration of today’s fusion experiments, IR systems have mostly been designed for off-line data analysis. For future long pulse devices (e.g., Wendelstein 7-X, ITER), a real time evaluation of the target temperature and heat flux is mandatory. This paper shows the development of a real time capable IR system for ASDEX Upgrade. A compact IR camera has been designed incorporating the necessary magnetic and electric shielding for the detector, cooler assembly. The camera communication is based on the Camera Link industry standard. The data acquisition hardware is based on National Instruments hardware, consisting of a PXIe chassis inside and a fibre optical connected industry computer outside the torus hall. Image processing and data evaluation are performed using real time LabVIEW.

  10. Efficient Real-time Video Transmission in Wireless Mesh Network

    Rajanikanth Aluvalu


    Full Text Available We are experiencing rapid improvement in video transmission and picture quality. The technologies are supporting us with real-time video transmissions such as video conferences and webinars. Soon reliable, simple, low cost real-time video will become essential, providing its extensive support to mobiles; PDA’s etc. These enhancements are going to affect the consumer behaviour, business culture. Video transmission includes transmitting packets through Wireless Mesh Network (WMN, which turned out to be a challenging scenario for real-time video services. Due to the existing nature of wireless networks include the presence of unpredictable delays and high packet error rates due to the error-prone nature of the wireless links. In this paper, we will propose a model which provides high capacity data transfer with reduced delay. We have simulated and achieved results with higher through put.

  11. Coordinated scheduling for dynamic real-time systems

    Natarajan, Swaminathan; Zhao, Wei


    In this project, we addressed issues in coordinated scheduling for dynamic real-time systems. In particular, we concentrated on design and implementation of a new distributed real-time system called R-Shell. The design objective of R-Shell is to provide computing support for space programs that have large, complex, fault-tolerant distributed real-time applications. In R-shell, the approach is based on the concept of scheduling agents, which reside in the application run-time environment, and are customized to provide just those resource management functions which are needed by the specific application. With this approach, we avoid the need for a sophisticated OS which provides a variety of generalized functionality, while still not burdening application programmers with heavy responsibility for resource management. In this report, we discuss the R-Shell approach, summarize the achievement of the project, and describe a preliminary prototype of R-Shell system.

  12. Specifying and verifying requirements of real-time systems

    Ravn, Anders P.; Rischel, Hans; Hansen, Kirsten Mark


    An approach to specification of requirements and verification of design for real-time systems is presented. A system is defined by a conventional mathematical model for a dynamic system where application specific states denote functions of real time. Specifications are formulas in duration calculus......, a real-time interval logic, where predicates define durations of states. Requirements define safety and functionality constraints on the system or a component. A top-level design is given by a control law: a predicate that defines an automation controlling the transition between phases of operation. Each...... control the distributed computation through synchronous events. Sensors and actuators relate events with system states. Verification is a deduction showing that a design implies requirements...

  13. Intelligent data management for real-time spacecraft monitoring

    Schwuttke, Ursula M.; Gasser, Les; Abramson, Bruce


    Real-time AI systems have begun to address the challenge of restructuring problem solving to meet real-time constraints by making key trade-offs that pursue less than optimal strategies with minimal impact on system goals. Several approaches for adapting to dynamic changes in system operating conditions are known. However, simultaneously adapting system decision criteria in a principled way has been difficult. Towards this end, a general technique for dynamically making such trade-offs using a combination of decision theory and domain knowledge has been developed. Multi-attribute utility theory (MAUT), a decision theoretic approach for making one-time decisions is discussed and dynamic trade-off evaluation is described as a knowledge-based extension of MAUT that is suitable for highly dynamic real-time environments, and provides an example of dynamic trade-off evaluation applied to a specific data management trade-off in a real-world spacecraft monitoring application.

  14. A Simplification of a Real-Time Verification Problem

    Saha, Indranil; Roy, Suman; 10.1007/978-3-540-75596-8_21


    We revisit the problem of real-time verification with dense dynamics using timeout and calendar based models and simplify this to a finite state verification problem. To overcome the complexity of verification of real-time systems with dense dynamics, Dutertre and Sorea, proposed timeout and calender based transition systems to model the behavior of real-time systems and verified safety properties using k-induction in association with bounded model checking. In this work, we introduce a specification formalism for these models in terms of Timeout Transition Diagrams and capture their behavior in terms of semantics of Timed Transition Systems. Further, we discuss a technique, which reduces the problem of verification of qualitative temporal properties on infinite state space of (a large fragment of) these timeout and calender based transition systems into that on clockless finite state models through a two-step process comprising of digitization and canonical finitary reduction. This technique enables us to ve...

  15. Real-time simulation of large-scale floods

    Liu, Q.; Qin, Y.; Li, G. D.; Liu, Z.; Cheng, D. J.; Zhao, Y. H.


    According to the complex real-time water situation, the real-time simulation of large-scale floods is very important for flood prevention practice. Model robustness and running efficiency are two critical factors in successful real-time flood simulation. This paper proposed a robust, two-dimensional, shallow water model based on the unstructured Godunov- type finite volume method. A robust wet/dry front method is used to enhance the numerical stability. An adaptive method is proposed to improve the running efficiency. The proposed model is used for large-scale flood simulation on real topography. Results compared to those of MIKE21 show the strong performance of the proposed model.

  16. Real-Time Parameter Estimation Using Output Error

    Grauer, Jared A.


    Output-error parameter estimation, normally a post- ight batch technique, was applied to real-time dynamic modeling problems. Variations on the traditional algorithm were investigated with the goal of making the method suitable for operation in real time. Im- plementation recommendations are given that are dependent on the modeling problem of interest. Application to ight test data showed that accurate parameter estimates and un- certainties for the short-period dynamics model were available every 2 s using time domain data, or every 3 s using frequency domain data. The data compatibility problem was also solved in real time, providing corrected sensor measurements every 4 s. If uncertainty corrections for colored residuals are omitted, this rate can be increased to every 0.5 s.

  17. Congestion Management Strategies of Real-Time Market

    Wang, Qi; Zhang, Chunyu; Ding, Yi


    The high penetration of distributed energy resources (DERs) will significantly challenge the power system operation and control due to their stochastic, intermittent, and fluctuation characteristics. This enhances the difficulty of congestion management of power systems in cross-border electricity...... market among different regions. For handling this, the Real-Time Market is proposed for balancing capacity trading against congestions. Several strategies for Real-Time Market dealing with congestions are proposed. The strategy of two-stage crossborder markets in Day-ahead, Intra-day and Real Time Market...... are introduced with the congestion constraints complied. Pre-Contingency strategy is proposed as the advance preparation for the future congestion, and In-Day re-dispatch is used for regulation. Accordingly, the requirements on facilities considering telemetry and remote control in a fast manner are discussed...

  18. Real time lobster posture estimation for behavior research

    Yan, Sheng; Alfredsen, Jo Arve


    In animal behavior research, the main task of observing the behavior of an animal is usually done manually. The measurement of the trajectory of an animal and its real-time posture description is often omitted due to the lack of automatic computer vision tools. Even though there are many publications for pose estimation, few are efficient enough to apply in real-time or can be used without the machine learning algorithm to train a classifier from mass samples. In this paper, we propose a novel strategy for the real-time lobster posture estimation to overcome those difficulties. In our proposed algorithm, we use the Gaussian mixture model (GMM) for lobster segmentation. Then the posture estimation is based on the distance transform and skeleton calculated from the segmentation. We tested the algorithm on a serials lobster videos in different size and lighting conditions. The results show that our proposed algorithm is efficient and robust under various conditions.

  19. Reduction Methods for Real-time Simulations in Hybrid Testing

    Andersen, Sebastian


    Hybrid testing constitutes a cost-effective experimental full scale testing method. The method was introduced in the 1960's by Japanese researchers, as an alternative to conventional full scale testing and small scale material testing, such as shake table tests. The principle of the method...... is to divide a structure into a physical substructure and a numerical substructure, and couple these in a test. If the test is conducted in real-time it is referred to as real time hybrid testing. The hybrid testing concept has developed significantly since its introduction in the 1960', both with respect...... without introducing further unknowns into the system. The basis formulation is shown to exhibit high precision and to reduce the computational cost significantly. Furthermore, the basis formulation exhibits a significant higher stability, than standard nonlinear algorithms. A real-time hybrid test...

  20. Modeling and Real-Time Simulation of UPFC

    Kimura, Misao; Takahashi, Choei; Kishibe, Hideto; Miyazaki, Yasuyuki; Noro, Yasuhiro; Iio, Naotaka

    We have developed a digital real time simulator of Power Electronics Controllers, so called FACTS (Flexible AC Transmission Systems) Controllers and/or Custom Power by using MATLABTM/SIMULINKTM and dSPACETM System. This paper describes the modeling and the calculation accuracy of a UPFC (Unified Power Flow Controller) model. Hence the developed simulator operates at a large time step, in order to improve simulation accuracy, a correction processing of the switching delay is implemented into the UPFC model. Calculation accuracy of the real time UPFC model is the same level as EMTDCTM results. We confirm stable operation of the developed UPFC model with connecting a commercial real time digital simulator (RTDSTM).

  1. An optimal real-time controller for vertical plasma stabilization

    Cruz, N; Coda, S; Duval, B P; Le, H B; Rodrigues, A P; Varandas, C A F; Correia, C M B A; Goncalves, B S


    Modern Tokamaks have evolved from the initial axisymmetric circular plasma shape to an elongated axisymmetric plasma shape that improves the energy confinement time and the triple product, which is a generally used figure of merit for the conditions needed for fusion reactor performance. However, the elongated plasma cross section introduces a vertical instability that demands a real-time feedback control loop to stabilize the plasma vertical position and velocity. At the Tokamak \\`a Configuration Variable (TCV) in-vessel poloidal field coils driven by fast switching power supplies are used to stabilize highly elongated plasmas. TCV plasma experiments have used a PID algorithm based controller to correct the plasma vertical position. In late 2013 experiments a new optimal real-time controller was tested improving the stability of the plasma. This contribution describes the new optimal real-time controller developed. The choice of the model that describes the plasma response to the actuators is discussed. The ...


    K. Susheel Kumar


    Full Text Available This paper presents an automated system for human face recognition in a real time background world fora large homemade dataset of persons face. The task is very difficult as the real time backgroundsubtraction in an image is still a challenge. Addition to this there is a huge variation in human face imagein terms of size, pose and expression. The system proposed collapses most of this variance. To detect realtime human face AdaBoost with Haar cascade is used and a simple fast PCA and LDA is used torecognize the faces detected. The matched face is then used to mark attendance in the laboratory, in ourcase. This biometric system is a real time attendance system based on the human face recognition with asimple and fast algorithms and gaining a high accuracy rate..

  3. Real-Time Statistical Modeling of Blood Sugar.

    Otoom, Mwaffaq; Alshraideh, Hussam; Almasaeid, Hisham M; López-de-Ipiña, Diego; Bravo, José


    Diabetes is considered a chronic disease that incurs various types of cost to the world. One major challenge in the control of Diabetes is the real time determination of the proper insulin dose. In this paper, we develop a prototype for real time blood sugar control, integrated with the cloud. Our system controls blood sugar by observing the blood sugar level and accordingly determining the appropriate insulin dose based on patient's historical data, all in real time and automatically. To determine the appropriate insulin dose, we propose two statistical models for modeling blood sugar profiles, namely ARIMA and Markov-based model. Our experiment used to evaluate the performance of the two models shows that the ARIMA model outperforms the Markov-based model in terms of prediction accuracy.

  4. Towards Real Time Simulation of Ship-Ship Interaction

    Lindberg, Ole; Bingham, Harry B.; Engsig-Karup, Allan Peter


    We present recent and preliminary work directed towards the development of a simplified, physics-based model for improved simulation of ship-ship interaction that can be used for both analysis and real-time computing (i.e. with real-time constraints due to visualization). The goal is to implement...... the model into a large maritime simulator for training of naval officers, in particular tug boat helmsmen. Tug boat simulators are used for training of communication and situation awareness during manoeuvre involved with towing of large vessels. A main objective of the work is to improve and enable more...... accurate (realistic) and much faster ship-wave and ship-ship simulations than are currently possible. The coupling of simulation with visualization should improve the visual experience such that it can be perceived as more realistic in training. Today the state-of-art in real-time ship-ship interaction...

  5. Compiling graphical real-time specifications into silicon

    Fränzle, Martin; Lüth, Karsten


    The basic algorithms underlying an automatic hardware synthesis environment using fully formal graphical requirements specifications as source language are outlined. The source language is real-time symbolic timing diagrams [FeyerabendJosko97], which are a metric-time temporal logic such that hard...... real-time constraints have to be dealt with. While automata-theoretic methods based on translating the specification to a finite automaton and constructing a winning strategy in the resulting omega-regular game could in principle be used, and do indeed provide the core algorithm, complexity withstands...... practical application of these methods. Therefore, a compositional extension is explored, which yields modular synthesis of multi-component controllers. Based on this, a second extension is proposed for efficiently dealing with hard real-time constraints....

  6. Real-time Flame Rendering with GPU and CUDA

    Wei Wei


    Full Text Available This paper proposes a method of flame simulation based on Lagrange process and chemical composition, which was non-grid and the problems associated with there grids were overcome. The turbulence movement of flame was described by Lagrange process and chemical composition was added into flame simulation which increased the authenticity of flame. For real-time applications, this paper simplified the EMST model. GPU-based particle system combined with OpenGL VBO and PBO unique technology was used to accelerate finally, the speed of vertex and pixel data interaction between CPU and GPU increased two orders of magnitude, frame rate of rendering increased by 30%, which achieved fast dynamic flame real-time simulation. For further real-time applications, this paper presented a strategy to implement flame simulation with CUDA on GPU, which achieved a speed up to 2.5 times the previous implementation.

  7. FPGA Implementation of Real-Time Ethernet for Motion Control

    Chen Youdong


    Full Text Available This paper provides an applicable implementation of real-time Ethernet named CASNET, which modifies the Ethernet medium access control (MAC to achieve the real-time requirement for motion control. CASNET is the communication protocol used for motion control system. Verilog hardware description language (VHDL has been used in the MAC logic design. The designed MAC serves as one of the intellectual properties (IPs and is applicable to various industrial controllers. The interface of the physical layer is RJ45. The other layers have been implemented by using C programs. The real-time Ethernet has been implemented by using field programmable gate array (FPGA technology and the proposed solution has been tested through the cycle time, synchronization accuracy, and Wireshark testing.

  8. Analyzing Real-Time Systems: Theory and Tools

    Hune, Thomas Seidelin

    The main topic of this dissertation is the development and use of methods for formal reasoning about the correctness of real-time systems, in particular methods and tools to handle new classes of problems. In real-time systems the correctness of the system does not only depend on the order in which...... actions take place, but also the timing of the actions. The formal reasoning presented here is based on (extensions of) the model of timed automata and tools supporting this model, mainly UPPAAL. Real-time systems are often part of safety critical systems e.g. control systems for planes, trains......, and successfully tested on a number of case studies. In particular, part of the Sidmar steel production plant, which is a case study of the Esprit VHS project, has been studied. Schedulability, without considering cost and optimality, has also been addressed using standard timed automata and UPPAAL. In order...

  9. A real-time VLC to UART protocol conversion system

    Deng, Jian-zhi; Yao, Meng; Cheng, Xiao-hui; Deng, Zhuo-hong


    A real-time visible light communication (VLC) to universal asynchronous receiver/transmitter (UART) conversion system is made up of a transmitter with a light emitting diode (LED) and a receiver with a photodiode (PD), by which a VLC system is connected to traditional communication modes, and the data are transferred by wireless visible light. UART packets are converted to light packets by the modulation of a 10 kHz on-off-keying (OOK) light signal, and the data losses in the transportation are avoided by the protection of a data buffer mechanism. The experimental results reveal that the real-time VLC to UART conversion system can provide a real-time VLC transmission way for two UART devices in not less than 10 m at a baud rate not less than 19 200 Bd with stable ambient lighting at the same time.

  10. Analysis of hybrid viscous damper by real time hybrid simulations

    Brodersen, Mark Laier; Ou, Ge; Høgsberg, Jan Becker


    Results from real time hybrid simulations are compared to full numerical simulations for a hybrid viscous damper, composed of a viscous dashpot in series with an active actuator and a load cell. By controlling the actuator displacement via filtered integral force feedback the damping performance...... of the hybrid viscous damper is improved, while for pure integral force feedback the damper stroke is instead increased. In the real time hybrid simulations viscous damping is emulated by a bang-bang controlled Magneto-Rheological (MR) damper. The controller activates high-frequency modes and generates drift...... in the actuator displacement, and only a fraction of the measured damper force can therefore be used as input to the investigated integral force feedback in the real time hybrid simulations....

  11. The VLBA Correlator---Real-Time in the Distributed ERA

    Wells, Donald C.


    The Correlator is the signal processing engine of the Very Long Baseline Array [VLBA]. Radio signals are recorded on special wideband digital recorders at the 10 VLBA antennas and are shipped to the Array Operations Center in Socorro, New Mexico, where they are played back simultaneously into the Correlator. Real-time software and firmware controls the playback drives to achieve synchronization, compute models of the wavefront delay, control the numerous modules of the Correlator, and record FITS files of the fringe visibilities at the back-end of the Correlator. The Correlator system contains a total of more than 100 programmable computers, which communicate by means of various protocols. The VLBA Correlator's dependence on network protocols is an example of the radical transformation of the real-time world over the past five years: real-time is becoming more like conventional computing.

  12. Real time capable infrared thermography for ASDEX Upgrade

    Sieglin, B.; Faitsch, M.; Herrmann, A.; Brucker, B.; Eich, T.; Kammerloher, L.; Martinov, S.


    Infrared (IR) thermography is widely used in fusion research to study power exhaust and incident heat load onto the plasma facing components. Due to the short pulse duration of today's fusion experiments, IR systems have mostly been designed for off-line data analysis. For future long pulse devices (e.g., Wendelstein 7-X, ITER), a real time evaluation of the target temperature and heat flux is mandatory. This paper shows the development of a real time capable IR system for ASDEX Upgrade. A compact IR camera has been designed incorporating the necessary magnetic and electric shielding for the detector, cooler assembly. The camera communication is based on the Camera Link industry standard. The data acquisition hardware is based on National Instruments hardware, consisting of a PXIe chassis inside and a fibre optical connected industry computer outside the torus hall. Image processing and data evaluation are performed using real time LabVIEW.

  13. Simultaneous real-time monitoring of multiple cortical systems

    Gupta, Disha; Hill, N. Jeremy; Brunner, Peter; Gunduz, Aysegul; Ritaccio, Anthony L.; Schalk, Gerwin


    Objective. Real-time monitoring of the brain is potentially valuable for performance monitoring, communication, training or rehabilitation. In natural situations, the brain performs a complex mix of various sensory, motor or cognitive functions. Thus, real-time brain monitoring would be most valuable if (a) it could decode information from multiple brain systems simultaneously, and (b) this decoding of each brain system were robust to variations in the activity of other (unrelated) brain systems. Previous studies showed that it is possible to decode some information from different brain systems in retrospect and/or in isolation. In our study, we set out to determine whether it is possible to simultaneously decode important information about a user from different brain systems in real time, and to evaluate the impact of concurrent activity in different brain systems on decoding performance. Approach. We study these questions using electrocorticographic signals recorded in humans. We first document procedures for generating stable decoding models given little training data, and then report their use for offline and for real-time decoding from 12 subjects (six for offline parameter optimization, six for online experimentation). The subjects engage in tasks that involve movement intention, movement execution and auditory functions, separately, and then simultaneously. Main results. Our real-time results demonstrate that our system can identify intention and movement periods in single trials with an accuracy of 80.4% and 86.8%, respectively (where 50% would be expected by chance). Simultaneously, the decoding of the power envelope of an auditory stimulus resulted in an average correlation coefficient of 0.37 between the actual and decoded power envelopes. These decoders were trained separately and executed simultaneously in real time. Significance. This study yielded the first demonstration that it is possible to decode simultaneously the functional activity of multiple

  14. New real time needle segmentation technique using grayscale Hough transformation

    Qiu, Wu; Zhou, Hua; Ding, Mingyue; Zhang, Songgeng


    Real-time needle segmentation and tracking is very important in image-guided surgery, biopsy, and therapy. In this paper, we described an automated technique to provide real-time needle segmentation from a sequence of 2-D ultrasound images for the use of guidance of a needle to the target in soft tissues. The Hough transform is used to find straight lines or analytic curves in binary image. Hough transform is applied usually to binary images. Hence one needs to convert, initially, the gray level image to a binary one (through thresholding, edge detection, or thinning) in order to apply the HT. While in the process of binarization, some information about line segments in the image may be lost when an inappropriate threshold is used. Gray-Scale Hough Transform can detect the line without binarization. Unfortunately, its high computational cost often prevents it from being applied in real-time applications without the help of specially designed hardware. In this paper, we proposed a needle segmentation technique based on a real-time gray-scale Hough transform. It is composed of an improved Gray Hough Transformation and a coarse-fine search strategy. Furthermore, the RTGHT (Real-Time Gray-Scale Hough Transform) technique is evaluated by patient breast biopsy images. Experiments with patient breast biopsy ultrasound (US) image sequences showed that our approach can segment the biopsy needle in real time (i.e., less than 60 ms) with the angular rms error of about 1° and the position rms error of about 0.5 mm an affordable PC computer without the help of specially designed hardware.

  15. High performance real-time flight simulation at NASA Langley

    Cleveland, Jeff I., II


    In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be deterministic and be completed in as short a time as possible. This includes simulation mathematical model computational and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, personnel at NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to a standard input/output system to provide for high bandwidth, low latency data acquisition and distribution. The Computer Automated Measurement and Control technology (IEEE standard 595) was extended to meet the performance requirements for real-time simulation. This technology extension increased the effective bandwidth by a factor of ten and increased the performance of modules necessary for simulator communications. This technology is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications of this technology are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC have completed the development of the use of supercomputers for simulation mathematical model computational to support real-time flight simulation. This includes the development of a real-time operating system and the development of specialized software and hardware for the CAMAC simulator network. This work, coupled with the use of an open systems software architecture, has advanced the state of the art in real time flight simulation. The data acquisition technology innovation and experience with recent developments in this technology are described.

  16. Infrared Image Real-time Enhancement Based on DSP

    DAI Shao-sheng; YUAN Xiang-hui; XUE Lian


    Since image real- time processing requires vast amount of computation and high- speed hardware,it is difficult to be implemented with general microcomputer system. In order to solve the problem,a powerful digital signal processing (DSP) hardware system is proposed,which is able to meet needs of image real-time processing. There are many approaches to enhance infrared image. But only histogram equalization is discussed because it is the most common and effective way. On the basis of histogram equalization principle, the specific procedures implemented in DSP are shown. At last the experimental results are given.

  17. The StarLite Project Prototyping Real-Time Software


    An Annual Report ( -A D-A242 032 Grant No. N00014-91-J-1102 t 1III iII I 1IIIII 11111i II’ October 1, 1990 - September 30, 1991 THE STARLITE PROJECT...1990 - September 30, 1991 THE STARLITE PROJECT PROTOTYPING REAL-TIME SOFTWARE I Submitted to: Scientific Officer Code: 1211 Dr. James G. Smith Office...DATES COVERED 4 October 1991 Annual 10/1/90 - 9/30/91 4. TITLE AND SUBTITLE S. FUNDING NUMBERS The Starlite Project - Prototyping Real-Time Software

  18. Requirements Specifications Checking of Embedded Real-Time Software

    WU Guoqing(毋国庆); SHU Fengdi(舒风笛); WANG Min(王敏); CHEN Weiqing(陈伟清)


    After introducing the overview of our requirements description model HRFSM,the paper presents a dynamic software execution model (DERTS) of embedded real-time software, which can integrate control flow, data flow and time. Based on DERTS, a checking method is also presented. It consists of three kinds of checking and can check the consistency and completeness of the requirement specifications of embedded real-time software. Besides providing information helpful to improve the efficiency of analyzing and checking specifications,the checking method is flexible, and easy to understand and to use for the analyst.

  19. Integration of Real-Time Data Into Building Automation Systems

    Mark J. Stunder; Perry Sebastian; Brenda A. Chube; Michael D. Koontz


    The project goal was to investigate the possibility of using predictive real-time information from the Internet as an input to building management system algorithms. The objectives were to identify the types of information most valuable to commercial and residential building owners, managers, and system designers. To comprehensively investigate and document currently available electronic real-time information suitable for use in building management systems. Verify the reliability of the information and recommend accreditation methods for data and providers. Assess methodologies to automatically retrieve and utilize the information. Characterize equipment required to implement automated integration. Demonstrate the feasibility and benefits of using the information in building management systems. Identify evolutionary control strategies.

  20. Weak Serializable Concurrency Control in Real-time Broadcast Environments


    Given the asymmetric communication capabilities in mobile real-time environments, traditional serializability-based approaches are too restrictive, unnecessary, and impractical. Thus propose the use of a new weaker correctness criterion is proposed. This paper first formally defines the new notion of correctness called weak serializability. After the necessary and sufficient conditions for weak serializability are shown, corresponding concurrency control protocol based on this criterion is outlined for real-time broadcast environments. Finally, the simulation results confirmed that the proposed techniques help mobile transactions to meet their deadlines and improve query response time.

  1. System security assessment in real-time using synchrophasor measurements

    Jóhannsson, Hjörtur; Wache, Markus


    assessment and sheds light on ongoing research activities that focus on exploiting wide-area synchrophasor measurements for real-time security assessment of sustainable power systems. At last, an mathematical mapping enabling informative visualization of the system state in respect to aperiodic rotor angle...... measures to ensure stable and secure operation of the system are necessary. Time stamped synchrophasor measurements lay the foundation for development of new real-time applications for security and stability assessment. The paper provides overview of existing solutions for synchrophasor based security...

  2. Towards Real Time Diagnostics of Hybrid Welding Laser/GMAW

    Timothy Mcjunkin; Dennis C. Kunerth; Corrie Nichol; Evgueni Todorov; Steve Levesque; Feng Yu; Robert Danna Couch


    Methods are currently being developed towards a more robust system real time feedback in the high throughput process combining laser welding with gas metal arc welding. A combination of ultrasonic, eddy current, electronic monitoring, and visual techniques are being applied to the welding process. Initial simulation and bench top evaluation of proposed real time techniques on weld samples are presented along with the concepts to apply the techniques concurrently to the weld process. Consideration for the eventual code acceptance of the methods and system are also being researched as a component of this project. The goal is to detect defects or precursors to defects and correct when possible during the weld process.

  3. Real time visual tracking of targets in six dimensions

    Walsh, Peter M.; Shawaga, Larry


    Six dimensional target information is produced by a target tracking vision system for use in real time target tracking by a robotic system. The vision system described in this paper produces three axes of position data and three axes of orientation data using a single camera which views a three dimensional target. The system performs target detection, target discrimination and determines the target position and orientation relative to the camera. As the target information is determined, it is communicated to a computer which is controlling the robot motion in real time. Details of the image processing algorithms and image processing hardware used in the vision system are discussed in the paper.

  4. Real-time Social Internet Data to Guide Forecasting Models

    Del Valle, Sara Y. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    Our goal is to improve decision support by monitoring and forecasting events using social media, mathematical models, and quantifying model uncertainty. Our approach is real-time, data-driven forecasts with quantified uncertainty: Not just for weather anymore. Information flow from human observations of events through an Internet system and classification algorithms is used to produce quantitatively uncertain forecast. In summary, we want to develop new tools to extract useful information from Internet data streams, develop new approaches to assimilate real-time information into predictive models, validate approaches by forecasting events, and our ultimate goal is to develop an event forecasting system using mathematical approaches and heterogeneous data streams.

  5. A Contribution to Real-Time Experiments in Remote Laboratories

    Zoltán Janík


    Full Text Available The paper is focused on realization of hard real-time control of experiments in on-line laboratories. The presented solution utilizes already developed on-line laboratory portal that is based on open-source Scilab environment. The customized solution is based on Linux RTAI platform with RTAI-XML server, Comedi and jRTAILab with support of ScicosLab environment. It generates real-time executable code that is used to operate student experiments performed on Humusoft CE152 Magnetic Levitation plant.

  6. Real-time digital signal processing fundamentals, implementations and applications

    Kuo, Sen M; Tian, Wenshun


    Combines both the DSP principles and real-time implementations and applications, and now updated with the new eZdsp USB Stick, which is very low cost, portable and widely employed at many DSP labs. Real-Time Digital Signal Processing introduces fundamental digital signal processing (DSP) principles and will be updated to include the latest DSP applications, introduce new software development tools and adjust the software design process to reflect the latest advances in the field. In the 3rd edition of the book, the key aspect of hands-on experiments will be enhanced to make the DSP principle

  7. Real-time medical collaboration services over the web.

    Andrikos, Christos; Rassias, Georgios; Tsanakas, Panayiotis; Maglogiannis, Ilias


    The gradual shift in modern medical practice, from working alone clinical doctors to MDTs (Multi-Disciplinary Teams), raises the need of online real-time collaboration among geographically distributed medical personnel. The paper presents a Web-based platform, featuring an efficient medical data management and exchange, for hosting real-time collaborative services. The presented work leverages state-of-the-art features of the web (technologies and APIs) to support client-side medical data processing. Moreover, to address the typical bandwidth bottleneck and known scalability issues of centralized data sharing, an indirect RPC (Remote Process Call) scheme is introduced through object synchronization over the WebRTC paradigm.

  8. Real-Time Information Extraction from Big Data


    I N S T I T U T E F O R D E F E N S E A N A L Y S E S Real-Time Information Extraction from Big Data Robert M. Rolfe...Information Extraction from Big Data Jagdeep Shah Robert M. Rolfe Francisco L. Loaiza-Lemos October 7, 2015 I N S T I T U T E F O R D E F E N S E...AN A LY S E S Abstract We are drowning under the 3 Vs (volume, velocity and variety) of big data . Real-time information extraction from big

  9. Atomic Stretch: Optimally bounded real-time stretching and beyond

    Jensen, Rasmus Ramsbøl; Nielsen, Jannik Boll


    Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color-modification, co......Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color...

  10. An Intelligent Real-Time System Architecture Implemented in ADA


    performed by the system is procedural in nature [ Wilber , 1989:75]. For example, if one was to create a fully autonomous system to pilot a modem fighter...Tindell, Ken , Bums, Alan, and Wellings, Andy, Allocating Hard Real Time Tasks (An NP-Hard Problem Made Easy), e-mail via ftp, 1992, Real Time Systems...Technology/ENS Wright-Patterson AFB, Ohio 45433-6583, Distribution Limited to DoD and DoD contractors only, April 1990. [ Wilber , 1989]. Wilber , George

  11. Organic semiconductors as real-time radiation detectors

    Suzuki, T., E-mail: [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan); Miyata, H., E-mail: [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Katsumata, M. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Nakano, S.; Matsuda, K. [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan); Tamura, M. [Carlit Holdings Co., Ltd., Tokyo 104-0031 (Japan)


    In this study, the possibility of using π-conjugated organic semiconducting polymers as real-time radiation detectors was explored. Polyaniline (PAni) was used to fabricate radiation sensors because of its relative long-term stability in air. Each fabricated sensor was then subjected to irradiation by α- and β-particles, and the real-time response was measured. The multichannel analyzer (MCA) data of the response signal for each irradiation was acquired and the detection efficiency, relative to the electrode bias voltage of the detector, was extracted.

  12. Real-time alerts and reminders using information systems.

    Wanderer, Jonathan P; Sandberg, Warren S; Ehrenfeld, Jesse M


    Adoption of information systems throughout the hospital environment has enabled the development of real-time physiologic alerts and clinician reminder systems. These clinical tools can be made available through the deployment of anesthesia information management systems (AIMS). Creating usable alert systems requires understanding of technical considerations. Various successful implementations are reviewed, encompassing cost reduction, improved revenue capture, timely antibiotic administration, and postoperative nausea and vomiting prophylaxis. Challenges to the widespread use of real-time alerts and reminders include AIMS adoption rates and the difficulty in choosing appropriate areas and approaches for information systems support.

  13. The Challenges Of Using Multicomputing In Real Time Visualapplications

    Ajay Anant Joshi


    Full Text Available Displaying visual data in a graphical distributed application is one of the main challenges and constraintsthat should be studied in real time applications. Many problems could be reported in using multicomputingfor real time visual applications. These problems are identified throughout this survey, and areclassified into two main categories. The first is computation and transfer time while the second is displayspeed. The real bottleneck in using grid or cloud computing in such applications is whether thecommunication time between nodes (inside the cloud increases to the point of degrading overallapplication performance. This survey paper describes the impact of time and communication speed onapplying visual systems on a grid or in cloud computing.

  14. Towards real time diagnostics of Hybrid Welding Laser/GMAW

    McJunkin, T. R.; Kunerth, D. C.; Nichol, C. I. [Idaho National Laboratory, Idaho Falls, ID 83415-3570 (United States); Todorov, E.; Levesque, S. [Edison Welding Institute, Columbus, OH (United States)


    Methods are currently being developed towards a more robust system real time feedback in the high throughput process combining laser welding with gas metal arc welding. A combination of ultrasonic, eddy current, electronic monitoring, and visual techniques are being applied to the welding process. Initial simulation and bench top evaluation of proposed real time techniques on weld samples are presented along with the concepts to apply the techniques concurrently to the weld process. Consideration for the eventual code acceptance of the methods and system are also being researched as a component of this project. The goal is to detect defects or precursors to defects and correct when possible during the weld process.

  15. A real time method for surface cleanliness measurement

    Bilmes, Gabriel Mario; Orzi, Daniel Jesús Omar; Martínez , Oscar E.; Lencina, Alberto


    The measurement of surface cleanliness is a signifi cant problem in many industrial and technological processes. Existing methods are based on laboratory procedures, that are not performed in real time, can not be automated, and usually are restricted to a small portion of the sample. In this study we describe a new method for real time measurement of the amount of surface dirt or contamination deposited on a surface. It relies on the ablation of the surface dirt film by means of a short l...

  16. Magneto-optical system for high speed real time imaging

    Baziljevich, M.; Barness, D.; Sinvani, M.; Perel, E.; Shaulov, A.; Yeshurun, Y.


    A new magneto-optical system has been developed to expand the range of high speed real time magneto-optical imaging. A special source for the external magnetic field has also been designed, using a pump solenoid to rapidly excite the field coil. Together with careful modifications of the cryostat, to reduce eddy currents, ramping rates reaching 3000 T/s have been achieved. Using a powerful laser as the light source, a custom designed optical assembly, and a high speed digital camera, real time imaging rates up to 30 000 frames per seconds have been demonstrated.

  17. Handheld portable real-time tracking and communications device

    Wiseman, James M [Albuquerque, NM; Riblett, Jr., Loren E. (Edgewood, NM); Green, Karl L [Albuquerque, NM; Hunter, John A [Albuquerque, NM; Cook, III, Robert N. (Rio Rancho, NM); Stevens, James R [Arlington, VA


    Portable handheld real-time tracking and communications devices include; a controller module, communications module including global positioning and mesh network radio module, data transfer and storage module, and a user interface module enclosed in a water-resistant enclosure. Real-time tracking and communications devices can be used by protective force, security and first responder personnel to provide situational awareness allowing for enhance coordination and effectiveness in rapid response situations. Such devices communicate to other authorized devices via mobile ad-hoc wireless networks, and do not require fixed infrastructure for their operation.

  18. Facial landmark detection in real-time with correlation filtering

    Contreras, Viridiana; Díaz-Ramírez, Víctor H.


    An algorithm for facial landmark detection based on template matched filtering is presented. The algorithm is able to detect and estimate the position of a set of prespecified landmarks by employing a bank of linear filters. Each filter in the bank is trained to detect a single landmark that is located in a small region of the input face image. The filter bank is implemented in parallel on a graphics processing unit to perform facial landmark detection in real-time. Computer simulation results obtained with the proposed algorithm are presented and discussed in terms of detection rate, accuracy of landmark location estimation, and real-time efficiency.

  19. Real-time PCR in Food Science: Introduction.

    Rodriguez-Lazaro, David; Hernandez, Marta


    Food safety and quality control programmes are increasingly applied throughout the production food chain in order to guarantee added value products as well as to minimize the risk of infection for the consumer. The development of real-time PCR has represented one of the most significant advances in food diagnostics as it provides rapid, reliable and quantitative results. These aspects become increasingly important for the agricultural and food industry. Different strategies for real-time PCR diagnostics have been developed including unspecific detection independent of the target sequence using fluorescent dyes such as SYBR Green, or by sequence-specific fluorescent oligonucleotide probes such as TaqMan probes or molecular beacons.

  20. Dynamic real-time hierarchical heuristic search for pathfinding.

    Naveed, Munir; Kitchin, Diane E.; Crampton, Andrew


    Movement of Units in Real-Time Strategy (RTS) Games is a non-trivial and challenging task mainly due to three factors which are constraints on CPU and memory usage, dynamicity of the game world, and concurrency. In this paper, we are focusing on finding a novel solution for solving the pathfinding problem in RTS Games for the units which are controlled by the computer. The novel solution combines two AI Planning approaches: Hierarchical Task Network (HTN) and Real-Time Heuristic Search (RHS)....