Designing an autonomous environment for mission critical operation of the EUVE satellite

Since the launch of NASA's Extreme Ultraviolet Explorer (EUVE) satellite in 1992, there has only been a handful of occurrences that have warranted manual intervention in the EUVE Science Operations Center (ESOC). So, in an effort to reduce costs, the current environment is being redesigned to utilize a combination of off-the-shelf packages and recently developed artificial intelligence (AI) software to automate the monitoring of the science payload and ground systems. The successful implementation of systemic automation would allow the ESOC to evolve from a seven day/week, three shift operation, to a seven day/week one shift operation. First, it was necessary to identify all areas considered mission critical. These were defined as follows: (1) The telemetry stream must be monitored autonomously and anomalies identified. (2) Duty personnel must be automatically paged and informed of the occurrence of an anomaly. (3) The 'basic' state of the ground system must be assessed. (4) Monitors should check that the systems and processes needed to continue in a 'healthy' operational mode are working at all times. (5) Network loads should be monitored to ensure that they stay within established limits. (6) Connectivity to Goddard Space Flight Center (GSFC) systems should be monitored as well, not just for connectivity of the network itself but also for the ability to transfer files. (7) All necessary peripheral devices should be monitored. This would include the disks, routers, tape drives, printers, tape carousel, and power supplies. (8) System daemons such as the archival daemon, the Sybase server, the payload monitoring software, and any other necessary processes should be monitored to ensure that they are operational. (9) The monitoring system needs to be redundant so that the failure of a single machine will not paralyze the monitors. (10) Notification should be done by means of looking though a table of the pager numbers for current 'on call' personnel. The software should be capable of dialing out to notify, sending email, and producing error logs. (11) The system should have knowledge of when real-time passes and tape recorder dumps will occur and should know that these passes and data transmissions are successful. Once the design criteria were established, the design team split into two groups: one that addressed the tracking, commanding, and health and safety of the science payload and another group that addressed the ground systems and communications aspects of the overall system

A survey on surfactant concentration in southern Caspian Sea

We determined concentration of surfactants as mg/I of LAS using Sublation-Methylen Blue method in the south Caspian Sea coastal areas extending from Astara to Bandar-e-Tourkaman. The method was based on the American Standard Method for Examination of Water and Wastewater. We analyzed 53 water samples and found an average surfactant concentration of 0.019mgi1 with the minimum and maximum being 0.008mg/I and 0.038mgi1 respectively. We conclude that presently, surfactant concentration is not critical in the coastal areas. However, care must be exercised interpreting these results considering the synergistic effects between the surfactants and heavy metals and oil hydrocarbons

Thermal Stress Analysis of Absorber Tube for a Parabolic Collector under Quasi-Steady State Condition

AbstractThe design of parabolic trough collectors is based on the concentration of solar heat flux on its absorber tube. This may be subjected to high thermal stresses which could cause deflection of the absorber tube and failure of its cover glass tube. Investigation of earlier studies on thermal gradient and thermal stresses demonstrates that so far, the issue is considered for steady state condition based on the assumption of constant solar heat flux distribution during the day hours. However, in practice, solar heat flux distribution on the receiver tube has continues changes with respect to time and deformation is basically transient. Due the low speed of sun during a day and for specific time intervals, the average solar radiation could be considered constant for thermal stress and deflection analysis. Hence, in this study, thermal gradients as well as thermal stresses in the absorber tube are numerically investigated in quasi steady condition. Due to the wide changes of solar radiation during a year, computations are performed for four specific days of Spring Equinox, Summer Solstice, Autumnal Equinox and Winter Solstice. To compute solar heat flux distribution, SolTrace software is used and three dimensional heat flux distribution is applied as an external boundary condition to calculate temperature distribution in the absorber tube. By using Von-Misses theory, maximum equivalent of total stress is computed. Maximum deflection is evaluated for various different inlet temperatures and hot oil mass flow rates in the common range of solar thermal power plants for atypical parabolic trough collector which is under construction in Shiraz, Iran

Correlation Between Intra-Abdominal Free Fluid and Solid Organ Injury in Blunt Abdominal Trauma

Background: In previous studies, the diagnostic value of Focused Assessment with Sonography for Trauma (FAST) has been evaluated but few studies have been performed on the relationship between the amount of free intra-abdominal fluid and organ injury in blunt abdominal trauma. To select patients with a higher probability of intra-abdominal injuries, several scoring systems have been proposed based on the results of FAST. Objectives: The aim of this study was to determine the prognostic value of FAST according to the Huang scoring system and to propose a cut-off point for predicting the presence of intra-abdominal injuries on the Computed Tomography (CT) scan. The correlation between age and Glasgow Coma Scale (GCS) and the presence of intra-abdominal injuries on the CT scan was also assessed. Patients and Methods: This study was performed on 200 patients with severe blunt abdominal trauma who had stable vital signs. For all patients, FAST-ultrasound was performed by a radiologist and the free fluid score in the abdomen was calculated according to the Huang score. Immediately, an intravenous contrast-enhanced abdominal CT scan was performed in all patients and abdominal solid organ injuries were assessed. Results were analyzed using Kruskal-Wallis test, Mann-Whitney test and ROC curves. The correlation between age and GCS and the presence of intra-abdominal injuries on CT-scan was also evaluated. Results: The mean age of the patients was 29.6 ± 18.3 years and FAST was positive in 67% of the subjects. A significant correlation was seen between the FAST score and the presence of organ injury on CT scan (P < 0.001). Considering the cut-off point of 3 for the free fluid score (with a range of 0-8), sensitivity, specificity, positive predictive value and negative predictive value were calculated to be 0.83, 0.98, 0.93, and 0.95, respectively. Age and GCS showed no significant correlation with intra-abdominal injuries. Conclusions: It seems that FAST examination for intra-abdominal fluid in blunt trauma patients can predict intra-abdominal injuries with very high sensitivity and specificity. Using the scoring system can more accurately determine the probability of the presence of abdominal injuries with a cut-off point of three

Evaluating the Catalytic Performance of La1-xCexNi1-yZnyO3 Nanostructure Perovskites in the Carbon Dioxide Reforming of Methane

AbstractIn this research nanostructure perovskites La1-xCexNi1-yZnyO3 were prepared by sol-gel auto-combustion method and their application were evaluated for methane reforming with carbon dioxide and syngas production. Catalysts were designed by Response Surface Method (RSM) based on central composite design (CCD) with three factors of catalyst characteristics, x, y and Tc. The prepared catalysts were examined in methane reforming process at 750 ˚C temperature and atmospheric pressure. Analysis of variance (ANOVA) showed that parameters don’t have any linear effect on catalytic activity and their effect is proportional to square form. Among this investigated parameters, Ni content effect is considerable and calcination temperature (Tc) has a partial effect. In this research R2 value was 94.88%. The optimum catalyst which determined by RSM was La0.60Ce0.40Ni0.81Zn0.19O3 in 747 ˚C calcination temperature that corresponds to empirical result. The XRD characterization of optimum catalyst showed that perovskite catalyst was formed in rhombohedra phase with nanostructure crystals and the SEM of optimum catalyst confirmed the nano scale of prepared particles

Relationship of CD147 kidney expression with various pathologic lesions, biochemical and demographic data in patients with classes III and IV of lupus nephritis

Background: Systemic lupus erythematosus (SLE) is a chronic inflammatory disorder that affects the kidney in around 50% of patients Objectives: The aim of this study was to assess CD147 expression with various pathologic lesions, biochemical and demographic data in patients with classes III and IV lupus nephritis. Patients and Methods: These patients with lupus nephritis classes II and IV by renal biopsy and pathology were enrolled in this study. The strength of CD147 staining on tubules, Bowman’s capsules, vessels and tuft of glomeruli was expressed as proportion of involvement. Results: In this study, 23 renal biopsies for lupus nephritis of classes III and IV (documented by immunofluorescence and light microscopic studies) were included. No significant difference of CD147 staining between classes was detected (P > 0.05). In addition, proportion of proteinuria was not related to CD147 staining in tubules, Bowman’s capsules, vessels and tuft of glomeruli in classes III and IV lupus nephritis (P > 0.05). There was no significant association of CD147 staining in tubules, Bowman’s capsules and vessels with serum creatinine (P > 0.05). However, an association between CD147 staining in tuft of glomeruli with serum creatinine was detected (r=0.623, P = 0.002). None of chronicity or activity percent of glomerular involvement in two classes of III or IV had a significant association with CD147 staining (P > 0.05). Conclusions: The significant association between CD147 staining in glomeruli with serum creatinine in lupus nephritis of classes III and IV revealed that inflammation at this area may have prognostic implicatio

Relationship of CD147 kidney expression with various pathologic lesions, biochemical and demographic data in patients with classes III and IV of lupus

Background: Systemic lupus erythematosus (SLE) is a chronic inflammatory disorder that affects the kidney in around 50% of patients Objectives: The aim of this study was to assess CD147 expression with various pathologic lesions, biochemical and demographic data in patients with classes III and IV lupus nephritis. Patients and Methods: These patients with lupus nephritis classes II and IV by renal biopsy and pathology were enrolled in this study. The strength of CD147 staining on tubules, Bowman’s capsules, vessels and tuft of glomeruli was expressed as proportion of involvement. Results: In this study, 23 renal biopsies for lupus nephritis of classes III and IV (documented by immunofluorescence and light microscopic studies) were included. No significant difference of CD147 staining between classes was detected (P > 0.05). In addition, proportion of proteinuria was not related to CD147 staining in tubules, Bowman’s capsules, vessels and tuft of glomeruli in classes III and IV lupus nephritis (P > 0.05). There was no significant association of CD147 staining in tubules, Bowman’s capsules and vessels with serum creatinine (P > 0.05). However, an association between CD147 staining in tuft of glomeruli with serum creatinine was detected (r=0.623, P = 0.002). None of chronicity or activity percent of glomerular involvement in two classes of III or IV had a significant association with CD147 staining (P > 0.05). Conclusions: The significant association between CD147 staining in glomeruli with serum creatinine in lupus nephritis of classes III and IV revealed that inflammation at this area may have prognostic implication

First report on the percentiles of the glomerular filtration rate in iranian children using the 2009 schwartz equations

The glomerular filtration rate (GFR) is widely considered the best overall index of renal function. The Schwartz equations are designed for measuring the GFR in children between 1 and 16 years of age. In the present study, we investigated the percentiles of the GFR in a general population of Iranian children with no known renal disease via the 2009 Schwartz equations (updated and combined equations). Between 2010 and 2011, we selected 687 children aged 7�16 years from the Iranian province of Isfahan. Blood samples were analyzed for blood urea nitrogen, creatinine, and cystatin C. For each child, we calculated the GFR using 2 Schwartz equations. The Wilcoxon test was applied to examine the differences in the estimated GFRs between the equations. To determine the correlation between the GFRs obtained via the updated and combined Schwartz equations in the boys and the girls and also for the correlation between age and the GFR, we performed the Pearson or Spearman correlation coefficients. The statistical analyses were conducted using MedCalc, version 12.1.4.0 (MedCalc Software, Mariakerke, Belgium). The mean GFR was 100.06±19.80 mL/min/1.73 m2 based on the updated equation and 96.10±18.44 mL/min/1.73 m2 according to the combined equation. No significant differences were observed between these equations in estimating the GFRs. The correlation analysis for determining the association between age and the GFR estimated by the updated (r=0.05, P=0.1) and combined (r=0.06, P=0.09) Schwartz equations was not statistically significant. In conclusion, in the current study we showed that the updated and combined Schwartz equations exhibited high concordance in estimating GFR values in this age group. © 2018, Shiraz University of Medical Sciences. All rights reserved

Multiagent System Architecture for Short-term Operation of Integrated Microgrids

The forthcoming smart grids are comprised of integrated microgrids operating in grid-connected and isolated mode with local generation, storage and demand response (DR) programs. The proposed model is based on three successive complementary steps for power transaction in the market environment. The first step is characterized as a microgrid’s internal market; the second concerns negotiations between distinct interconnected microgrids; and finally, the third refers to the actual electricity market. The proposed approach is modeled and tested using a MAS framework directed to the study of the smart grids environment, including the simulation of electricity markets. This is achieved through the integration of the proposed approach with the MASGriP (Multi-Agent Smart Grid Platform) system