Correspondence between solar load ratio method for passive water wall systems and f-Chart performance estimates

Acoustic emission (AE) is an important nondestructive evaluation (NDE) technique used in the field of structural engineering for both case local and global monitoring. In this study AE technique with a new approach was employed to investigate the process of fracture formation in reinforced concrete structure. A number of reinforced concrete (RC) one story frames were tested under loading cycle and were simultaneously monitored using AE. The AE test data was analyzed using the relaxation ratio and calm and load ratio method. Also, the relaxation ratio was dominated with approaching load to 58% of the ultimate load. In addition three levels of damage using calm and load ratio were distinguished. The trend of relaxation ratio and calm and load ratio method during loading and unloading showed that these methods are strongly sensitive with cracks growth in RC frame specimens and were able to indicate the levels of damage. Also, results showed that AE can be considered as a viable method to predict the remaining service life of reinforced concrete. In addition, with respect to the results obtained from relaxation ratio and, load and calm ratio indicated, a new chart is proposed.

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A Calibration of the Solar Load Ratio Method to Determine the Heat Gain in PV-Trombe Walls

Energies ◽

10.3390/en15010328 ◽

2022 ◽

Vol 15 (1) ◽

pp. 328

Author(s):

Roberto Bruno ◽

Piero Bevilacqua ◽

Daniela Cirone ◽

Stefania Perrella ◽

Antonino Rollo

Keyword(s):

Dimensionless Parameter ◽

Load Ratio ◽

Empirical Method ◽

Ratio Method ◽

Passive System ◽

Actual Performance ◽

Simulation Tools ◽

Trombe Wall ◽

Visual Impact ◽

Energy Gains

The Trombe wall is a passive system used in buildings that indirectly transfers thermal energy to the adjacent environment by radiation and convection, and directly by the thermo-circulation that arises in the air cavity delimited between a transparent and an absorbing surface. Nevertheless, the latter is painted black to increase the energy gains, but this produces a negative visual impact and promotes the overheating risk in summer. To mitigate these aspects, a hybrid Trombe wall equipped with PV panels can be employed. The PV installation results in a more pleasing wall appearance and the overheating risk reduces because part of the absorbed solar radiation is transformed into electricity. To determine the actual performance of a such system, transient simulation tools are required to consider properly the wall thermal storage features, variation of the optical properties, air thermo-circulation, and PV power production. Alternatively, regarding the traditional Trombe wall, the literature provides a simplified empirical method based on the dimensionless parameter solar load ratio (SLR) that allows for preliminary evaluations and design. In this paper, the SLR method was calibrated to determine the monthly auxiliary energy to be supplied in buildings equipped with PV-Trombe walls in heating applications. The SLR method was tuned by a multiple linear regression by data provided by TRNSYS simulation that allowed to obtain the energy performances in actual conditions of PV-Trombe walls installed on the same building but located in different localities. The comparison between the TRNSYS results and the calibrated SLR method determined average errors ranging between 0.7% and 1.4%, demonstrating the validity of the proposed methodology.

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X-Ray Analysis of Frozen Hydrated Sections:The Unconventional Approach

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100056065 ◽

1982 ◽

Vol 40 ◽

pp. 754-757

Author(s):

R. Beeuwkes ◽

A. Saubermann ◽

P. Echlin ◽

S. Churchill

Keyword(s):

Ratio Method ◽

Frozen Sections ◽

Technical Problems ◽

Sample Handling ◽

X Ray ◽

Common Group ◽

Ideal Method ◽

Classic Paper ◽

Physical Principles ◽

The Ideal

Fifteen years ago, Hall described clearly the advantages of the thin section approach to biological x-ray microanalysis, and described clearly the ratio method for quantitive analysis in such preparations. In this now classic paper, he also made it clear that the ideal method of sample preparation would involve only freezing and sectioning at low temperature. Subsequently, Hall and his coworkers, as well as others, have applied themselves to the task of direct x-ray microanalysis of frozen sections. To achieve this goal, different methodological approachs have been developed as different groups sought solutions to a common group of technical problems. This report describes some of these problems and indicates the specific approaches and procedures developed by our group in order to overcome them. We acknowledge that the techniques evolved by our group are quite different from earlier approaches to cryomicrotomy and sample handling, hence the title of our paper. However, such departures from tradition have been based upon our attempt to apply basic physical principles to the processes involved. We feel we have demonstrated that such a break with tradition has valuable consequences.

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Efficiency of classification as a function of number of jobs, percent rejected and validity and intercorrelation of job performance estimates

PsycEXTRA Dataset ◽

10.1037/e464492008-001 ◽

1956 ◽

Author(s):

Hubert E. Brogden

Keyword(s):

Job Performance ◽

Performance Estimates

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Are unskilled drivers aware of their deficiencies? How driving skills influence the accuracy of driving performance estimates

PsycEXTRA Dataset ◽

10.1037/e578572012-008 ◽

2009 ◽

Author(s):

David G. Kidd ◽

Christopher A. Monk

Keyword(s):

Driving Performance ◽

Driving Skills ◽

Performance Estimates

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Predicting Fetal Chromosome Anomalies in the First Trimester Using Pregnancy Associated Plasma Protein-A: A Comparison of Statistical Methods

Methods of Information in Medicine ◽

10.1055/s-0038-1634910 ◽

1993 ◽

Vol 32 (02) ◽

pp. 175-179 ◽

Cited By ~ 7

Author(s):

B. Brambati ◽

T. Chard ◽

J. G. Grudzinskas ◽

M. C. M. Macintosh

Keyword(s):

Logistic Regression ◽

General Population ◽

Likelihood Ratio ◽

False Positive ◽

False Positive Rate ◽

Ratio Method ◽

Detection Rates ◽

Gaussian Distributions ◽

Positive Rate ◽

Likelihood Ratio Method

Abstract:The analysis of the clinical efficiency of a biochemical parameter in the prediction of chromosome anomalies is described, using a database of 475 cases including 30 abnormalities. A comparison was made of two different approaches to the statistical analysis: the use of Gaussian frequency distributions and likelihood ratios, and logistic regression. Both methods computed that for a 5% false-positive rate approximately 60% of anomalies are detected on the basis of maternal age and serum PAPP-A. The logistic regression analysis is appropriate where the outcome variable (chromosome anomaly) is binary and the detection rates refer to the original data only. The likelihood ratio method is used to predict the outcome in the general population. The latter method depends on the data or some transformation of the data fitting a known frequency distribution (Gaussian in this case). The precision of the predicted detection rates is limited by the small sample of abnormals (30 cases). Varying the means and standard deviations (to the limits of their 95% confidence intervals) of the fitted log Gaussian distributions resulted in a detection rate varying between 42% and 79% for a 5% false-positive rate. Thus, although the likelihood ratio method is potentially the better method in determining the usefulness of a test in the general population, larger numbers of abnormal cases are required to stabilise the means and standard deviations of the fitted log Gaussian distributions.

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In Vivo Effect of Suloctidil as an Antiplatelet Agent

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646799 ◽

1979 ◽

Vol 41 (03) ◽

pp. 465-474 ◽

Cited By ~ 7

Author(s):

Marcia R Stelzer ◽

Thomas S Burns ◽

Robert N Saunders

Keyword(s):

Ex Vivo ◽

Antiplatelet Agent ◽

Ratio Method ◽

Platelet Aggregate ◽

Permanent Effect ◽

Platelet Aggregates ◽

5 Ht Uptake ◽

High Doses

SummaryThe relationship between the effects of suloctidil in vivo as an antiplatelet agent and in vitro as a modifier of platelet serotonin (5-HT) parameters was investigated. Suloctidil was found to be effective in reducing platelet aggregates formation in the retired breeder rat as determined using the platelet aggregate ratio method (PAR) with an ED50 of 16.1 mg/kg 24 hours post administration. In contrast to the hypothesis that 5-HT depletion is involved in the anti-aggregatory mechanism of suloctidil, no correlation was found between platelet 5- HT content and this antiplatelet activity. Reduction of platelet 5-HT content required multiple injections of high doses (100 mg/kg/day) of suloctidil. Suloctidil administration for 8 days at 100 mg/kg/day, which lowered platelet 5-HT content by 50%, resulted in no permanent effect on ex vivo platelet 5-HT uptake or thrombin-induced release, nor alteration in the plasma 5-HT level. However, these platelets exhibited a short-lived, significant increase in percent leakage of 5-HT after 30 minutes of incubation. Therefore, suloctidil treatment at high doses may with time result in platelet 5-HT depletion, however this effect is probably not related to the primary anti-aggregatory activity of the drug.

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