scholarly journals A Methodology for Buildings Access to Solar Radiation in Sustainable Cities

2019 ◽  
Vol 11 (23) ◽  
pp. 6596 ◽  
Author(s):  
L. M. Fernández-Ahumada ◽  
J. Ramírez-Faz ◽  
R. López-Luque ◽  
A. Márquez-García ◽  
M. Varo-Martínez
Keyword(s):  
Solar Radiation ◽  
Regression Model ◽  
Mean Value ◽  
Urban Morphology ◽  
Sustainable Cities ◽  
Energy Sustainability ◽  
Solar Radiation Incident ◽  
Solar Access ◽  
The One

The growing need to improve the environmental and energy sustainability of buildings involves the use of solar radiation incident on their surfaces. However, in cities, this task is complicated due to the constructive geometry that leads to shading between buildings. In this context, this work presents a study of solar access to the façades of buildings in cities. The methodology is based on the determination of the incident annual solar radiation in 121 significant points of each façade considering the twelve representative days of the year. To characterize the influence of the different city typologies on solar access, the urban solar coefficient is proposed. A study of two neighborhoods in Cordoba (Spain) with different urban settings have been analyzed. Specifically, two typologies of neighborhoods have been compared: one with “L-shaped” and “U-shaped blocks” and another with “Grouped blocks”. For both of them, the Urban Solar Coefficient has been calculated, obtaining a higher mean value for the neighborhood with “L-shaped” and “U-shaped blocks” (0.317) than for the one with “Grouped blocks” (0.260). Accordingly, the results show that urban morphology can influence the Urban Solar Coefficient and solar access. Finally, a regression model for each neighborhood has been obtained in order to determine the dependence of the Urban Solar Coefficient on neighborhood geometry factors.

Determination of the Red Blood Cell Apparent Membrane Elastic Modulus From Viscometric Measurements

1990 ◽  
Vol 112 (3) ◽  
pp. 241-249 ◽  
Author(s):  
A. Drochon ◽  
D. Barthes-Biesel ◽  
C. Lacombe ◽  
J. C. Lelievre
Keyword(s):  
Elastic Modulus ◽  
Heat Exposure ◽  
Mean Value ◽  
Good Discrimination ◽  
Shear Elastic Modulus ◽  
Dilute Suspensions ◽  
Dilute Suspension ◽  
The One ◽  
Internal Viscosity

Rhelogical measurements on a dilute suspension of red blood cells (RBCs) are interpreted by means of a microheological model that relates the shear evolution of the apparent viscosity to the intrinsic properties of the suspended particles. It is then possible to quantify the average deformability of a RBC population in terms of a mean value of the membrane shear elastic modulus, Es. Dilute suspensions of erthrocytes exhibit a shear-thinning behavior with a constant high shear viscosity. This behavior is identical to the one predicted for a suspension of spherical capsules where the same phenomena of deformation and orientation prevail. A comparison between theoretical and experimental curves yields a mean value of Es, assuming all other cell properties—internal viscosity, geometry—to be otherwise equal. In Dextran, the values of Es for normal RBCs are found to be of order 3.10−6 N/m. For erythrocytes hardened by heat exposure for 15 minutes at 48°C, the increase in Es reaches 45 percent. This procedure of shear elastic modulus determination is easy to perform and seems to give a good discrimination between normal and altered erythrocytes.

scholarly journals Environmental, economic and energetic benefits from implantation of several modes of solar collector movements

2021 ◽  
Vol 12 (3) ◽  
pp. 313-321
Author(s):  
Mustafa Hamad ◽  
Mhanna Obaid
Keyword(s):  
Solar System ◽  
Solar Radiation ◽  
Solar Collector ◽  
The Other ◽  
Tracking Systems ◽  
Optical Efficiency ◽  
Solar Radiation Intensity ◽  
Solar Radiation Incident ◽  
The One ◽  
East West

In this research, the performance of a moving solar system on two axes was studied, the east-west axis, this axis represents the tilt angle of the solar collector. The other movement is the surface's rotation around the perpendicular axis on the surface in the east and west directions, which in turn represents the azimuth angle of the solar collector. All possibilities for these movements were also studied, in order to reach the optimal option, which in turn depends on the importance of alication and the available space on the one hand, and the economic conditions on the other hand. The maximum value of solar radiation intensity was adopted as a guide to compare the performance of six options for tracking systems. Despite the high costs of tracking systems, they often have a positive economic return, as these systems increase the efficiency of the solar system, whether it is electric or thermal twice, the first one by increasing the intensity of the solar radiation incident on the solar collector, and the second one by increasing the optical efficiency of the solar collectors and thus increasing the overall efficiency of the device. The percentage of increase in the sixth type of solar energy is about 38% compared to the fixed mode. The minimum optical efficiency of the dual tracking mode has been found as 84%, while for fixed mode is about 48%.

The mystery of Copernicus’ star catalogue (The second part) The system of time and determination of the Earth’s triple motion

2020 ◽  
Vol 960 (6) ◽  
pp. 56-64
Author(s):  
S.A. Tolchelnikova
Keyword(s):  
Mean Value ◽  
Time System ◽  
Star Catalogue ◽  
The Earth ◽  
Mechanical Models ◽  
The Mean ◽  
Axis Rotation ◽  
The One ◽  
The Universe

Objecting to those who consider Copernicus’s work as repeating the achievements of Antiquity, we pay attention to his determination of uniform time necessary for applying any mathematical theory in particular, the one describing the observed uneven movements through a composition of circular and uniform rotations. Using the Egyptian year of 365 solar days, Copernicus analyzed the observations for the period from the first Olympiad up to his own observations. Generalizing the results of observations of two millennia and reducing them to the unique time system enabled his explaining the observed precession of equinoxes, and changes in the angle of inclination of the Earth’s equator to ecliptic by the lag of the Earth’s center rotation from that of its axis, simultaneously to exclude empty spheres from the medieval mechanical models of the Universe. Analyzing the observations of the period 4 times longer than that of Ptolemy, Copernicus managed to obtain the mean value of precession and the period of the Earth axis rotation practically coinciding with modern determinations. The proof of “the triple motion of the Earth” was necessary for affirmation of heliocentric system of the world.

A computer linear regression model to determine ventilatory anaerobic threshold

1982 ◽  
Vol 52 (5) ◽  
pp. 1349-1352 ◽  
Author(s):  
G. W. Orr ◽  
H. J. Green ◽  
R. L. Hughson ◽  
G. W. Bennett
Keyword(s):  
Gas Exchange ◽  
Linear Regression ◽  
Regression Model ◽  
Anaerobic Threshold ◽  
Break Point ◽  
Mean Value ◽  
Ventilatory Anaerobic Threshold ◽  
Response To Exercise ◽  
Exchange Data

The anaerobic threshold has generally been determined by simple visual inspection of ventilation or other gas-exchange data obtained during incremental exercise. To establish objective criteria for the determination of anaerobic threshold, a computer algorithm has been developed that models the ventilatory response to exercise using multisegment linear regression. The best-fit regression model is chosen by minimizing the pooled residual sum of squares . The anaerobic threshold is reported as the first break point in that model. The computer-determined anaerobic threshold values for 37 subjects were compared with subjectively determined values as chosen by four independent observers. The observers' estimates, when pooled to yield a single a single value for each subject, gave a mean value for the gas-exchange anaerobic threshold of 2.26 +/- 0.69 l/min. The estimates by the computer method averaged 2.21 +/- 0.65 l/min. The correlation coefficient for these two methods was 0.94.

scholarly journals Determination of solar window for Baghdad city using pv system program

2014 ◽  
Vol 11 (2) ◽  
pp. 590-597
Author(s):  
Baghdad Science Journal
Keyword(s):  
Solar Radiation ◽  
Tilt Angle ◽  
Solar Panel ◽  
Pv System ◽  
Solar Radiation Incident ◽  
Left And Right ◽  
Solar Window ◽  
Fixed Panel ◽  
System Program

Been using a pv system program to determine the solar window for Baghdad city . the solar window for any location can be determine by deviating left and right from the geographical south as well as deviation according to the amount of tilt angle with the horizon for fixed panel so that will not change the average of solar radiation incident over the whole year and this lead to help in the process of installation of fixed solar panel without any effect on annual output .the range of solar window for Baghdad city between two angles ( -8 - +8 ) degrees left to right of the geographical south and tilt angle that allowed for the horizon range between angles (21- 30) degrees so that the amount of solar radiation that falling on the solar panel in this range of fixed angles about5.6 kw.h/m2 yearl.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

1967 ◽  
Vol 18 (01/02) ◽  
pp. 198-210 ◽  
Author(s):  
Ronald S Reno ◽  
Walter H Seegers
Keyword(s):  
Prothrombin Time ◽  
Factor Vii ◽  
Two Stage ◽  
Pronounced Increase ◽  
One Stage ◽  
Assay Procedure ◽  
Bovine Plasma ◽  
The One ◽  
Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

SIMPLIFIED DEXAMETHASONE SUPPRESSION TEST

1969 ◽  
Vol 61 (2) ◽  
pp. 219-231 ◽  
Author(s):  
V. H. Asfeldt
Keyword(s):  
Cushing’S Syndrome ◽  
Normal Subjects ◽  
Cushing's Syndrome ◽  
Dexamethasone Suppression Test ◽  
Clinical Value ◽  
Suppression Test ◽  
The One ◽  
Steroid Excretion ◽  
Dexamethasone Suppression

ABSTRACT This is an investigation of the practical clinical value of the one mg dexamethasone suppression test of Nugent et al. (1963). The results, evaluated from the decrease in fluorimetrically determined plasma corticosteroids in normal subjects, as well as in cases of exogenous obesity, hirsutism and in Cushing's syndrome, confirm the findings reported in previous studies. Plasma corticosteroid reduction after one mg of dexamethasone in cases of stable diabetes was not significantly different from that observed in control subjects, but in one third of the insulin-treated diabetics only a partial response was observed, indicating a slight hypercorticism in these patients. An insufficient decrease in plasma corticosteroids was observed in certain other conditions (anorexia nervosa, pituitary adenoma, patients receiving contraceptive or anticonvulsive treatment) with no hypercorticism. The physiological significance of these findings is discussed. It is concluded that the test, together with a determination of the basal urinary 17-ketogenic steroid excretion, is suitable as the first diagnostic test in patients in whom Cushing's syndrome is suspected. In cases of insufficient suppression of plasma corticosteroids, further studies, including the suppression test of Liddle (1960), must be carried out.

Determination of the Probability Distribution of the Mean Sound Level

2010 ◽  
Vol 35 (4) ◽  
pp. 543-550 ◽  
Author(s):  
Wojciech Batko ◽  
Bartosz Przysucha
Keyword(s):  
Probability Distribution ◽  
Probability Distribution Function ◽  
Mean Value ◽  
Sound Level ◽  
Function Form ◽  
Noise Levels ◽  
Logarithmic Mean ◽  
The Mean ◽  
Estimation Of Uncertainty

AbstractAssessment of several noise indicators are determined by the logarithmic mean <img src="/fulltext-image.asp?format=htmlnonpaginated&src=P42524002G141TV8_html\05_paper.gif" alt=""/>, from the sum of independent random resultsL1;L2; : : : ;Lnof the sound level, being under testing. The estimation of uncertainty of such averaging requires knowledge of probability distribution of the function form of their calculations. The developed solution, leading to the recurrent determination of the probability distribution function for the estimation of the mean value of noise levels and its variance, is shown in this paper.

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