scholarly journals A Study on the Effects of Vertical Mass Irregularity on Seismic Behavior of BRBFs and CBFs

2020 ◽  
Vol 10 (23) ◽  
pp. 8314
Author(s):  
Armin Karami ◽  
Shahrokh Shahbazi ◽  
Mahdi Kioumarsi
Keyword(s):  
Urban Areas ◽  
Seismic Behavior ◽  
Steel Structures ◽  
Mean Value ◽  
Far Field ◽  
Braced Frames ◽  
Regular Structures ◽  
Irregular Structures ◽  
The Mean ◽  
Economic Constraints

Today, architectural application and economic constraints require that vertical-irregular structures be constructed in urban areas. Proposing methods to minimize damage to these structures during earthquakes is therefore crucial. Strict regulations have been enforced for the design and analysis of irregular structures given their higher vulnerability to damage compared to that of regular structures. The present study aimed to evaluate eight regular and irregular 10-story and 15-story steel structures with buckling-restrained braces frames (BRBFs) and concentric braced frames (CBFs) in terms of their responses to twelve far-field earthquakes. According to the obtained results, the mean value of maximum drift, top floor displacement and floor acceleration were higher in both regular and irregular structures with BRBFs than in those with CBFs.

scholarly journals Mengevaluasi Efektivitas Pelaksanaan Program Kota Tanpa Kumuh (Studi Kasus pada Wilayah Kota Langsa)

2021 ◽  
Vol 12 (2) ◽  
pp. 200-213
Author(s):  
Safrizal Safrizal ◽  
Safuridar Safuridar ◽  
Muhammad Fuad
Keyword(s):  
Urban Areas ◽  
Mean Value ◽  
Primary Data ◽  
Community Members ◽  
Government Programs ◽  
City Community ◽  
The Mean ◽  
The Government ◽  
The City ◽  
Slum Areas

Population growth and development can lead to excesses for the emergence of slum areas, which are often seen as a potential problem in urban areas. To reduce the problems of housing and slum areas, one of the government programs is the City Without Slum (in Indonesia called KOTAKU) program. This study aims to analyze the effectiveness of the program in Langsa City and identify the inhibiting factors of this program. 166 respondents were all village chiefs in Langsa City, community members who were directly or indirectly involved in the program, as well as other stakeholders. Primary data were collected through a questionnaire. The effectiveness evaluation is calculated using the mean value as a percentage of each indicator. The results found that the KOTAKU program was considered effective as an effort to reduce slum settlements in Langsa City. However, several factors were identified that were the main obstacles in the implementation of the program.

A scenario-based methodology for determining fire resistance ratings of irregular steel structures

2019 ◽  
Vol 23 (1) ◽  
pp. 89-103
Author(s):  
Behrouz Behnam
Keyword(s):  
Fire Resistance ◽  
Safety Margin ◽  
Steel Structures ◽  
Soft Story ◽  
Regular Structures ◽  
Natural Fires ◽  
Irregular Structures ◽  
Fire Scenarios ◽  
Fire Resistance Rating ◽  
Resistance Rating

This article investigates the response of irregular steel structures under natural fires. As the severity and duration of natural fires depend on many factors, a probabilistic-based approach known as two-level factorial design is used, whereby possible fire scenarios are considered based on the minimum and maximum values of the involved factors. Two seven-story regular steel structures with three span lengths of 5500 and 7000 mm are designed to meet a 2.0-hr fire resistance rating based on the ISO834 fire. Two types of irregularities, setback and soft story, are then imposed on the regular structures to make them irregular. The regular and irregular structures are then exposed to the fire scenarios (32 in total) to evaluate their fire resistance ratings. The results show that while the regular structures are able to meet the required fire resistance rating under all of the fire scenarios, this is not the case for the irregular structures. It is shown that the reduction in the fire resistance ratings of the setback and the soft-story structures can be as low as 45% and 33% that of the required fire resistance ratings, respectively. Also, the setback irregular structures tend to collapse laterally, hence endangering the safety of adjacent buildings. To address the above deficiencies, it is proposed here that the maximum surface temperature on the structural members should be limited to 415°C–460°C. Alternatively, providing a 20%–25% increase in the insulation thickness can provide the required safety margin as dictated by fire codes.

scholarly journals Transmissibility of acute haemorrhagic conjunctivitis in small-scale outbreaks in Hunan Province, China

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Siyu Zhang ◽  
Qingqing Hu ◽  
Zhihong Deng ◽  
Shixiong Hu ◽  
Fuqiang Liu ◽  
...  
Keyword(s):  
Health Education ◽  
Urban Areas ◽  
Primary Schools ◽  
Mean Value ◽  
School Closure ◽  
Hunan Province ◽  
Small Scale ◽  
Rural And Urban Areas ◽  
Rural And Urban ◽  
The Mean

AbstractAcute haemorrhagic conjunctivitis (AHC) outbreaks are reported frequently in China. However, the transmissibility of AHC remains unclear. This study aimed to calculate the transmissibility of the disease with and without interventions. An AHC outbreak dataset from January 2007 to December 2016 in different schools was built in Hunan Province. A Susceptible-Infectious-Recovered (SIR) model was adopted to calculate the effective reproduction number (Reff) of AHC. Reff was divided into two parts (Runc and Rcon) where Runc and Rcon represent the uncontrolled and controlled Reff , respectively. Based on Runc and Rcon, an index of effectiveness of countermeasures (Ieff) was developed to assess the effectiveness of countermeasures in each outbreak. During the study period, 34 AHC outbreaks were reported in 20 counties of 9 cities in Hunan Province, with a mean total attack rate of 7.04% (95% CI: 4.97–9.11%). The mean Runc of AHC outbreaks was 8.28 (95% CI: 6.46–10.11). No significance of Runc was observed between rural and urban areas (t = −1.296, P = 0.205), among college, secondary, and primary schools (F = 0.890, P = 0.459), different levels of school population (F = 0.738, P = 0.538), and different number of index cases (F = 1.749, P = 0.180). The most commonly implemented countermeasures were case isolation, treatment, and health education, followed by environment disinfection, symptom surveillance, and school closure. Social distance, prophylaxis, and stopping eye exercises temporary were implemented occasionally. The mean value of Rcon was 0.16 (range: 0.00–1.50). The mean value of Ieff was 97.16% (range: 71.44–100.00%). The transmissibility of AHC is high in small-scale outbreaks in China. Case isolation, treatment, and health education are the common countermeasures for controlling the disease.

scholarly journals Impact of Nitrogen Fertilizer use on Soil Ecosystem Integrity in the Greater Port Harcourt Region, Nigeria

2021 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Wanjala, MP ◽  
Odokuma, L ◽  
Etela I ◽  
Ramkat, R ◽  
Odogwu, BA ◽  
...  
Keyword(s):  
Urban Areas ◽  
Crop Yields ◽  
Mean Value ◽  
Npk Fertilizers ◽  
Fertilizer Use ◽  
Soil Microbial ◽  
Port Harcourt ◽  
The Mean ◽  
Agricultural Areas ◽  
The Impact

Fertilizers are used in agriculture to increase crop yields, but if they are misused, they can harm the integrity of soil ecosystems. The study's aim was to look at the impact of inorganic fertilizers on soil microbial populations in selected soils in the Greater Port Harcourt Area using Lethal Concentration 50 (LC50). The results revealed that the use of inorganic fertilizer altered soil microbial characteristics in three different settings: agricultural, urban, and industrial. For agricultural areas the maximum NPKB mean value was 0.70±0.76 ppm which was higher than the mean value of the control location of 0.23±0.00 ppm. In the agricultural area, UREA tolerant fungi had a lower LC50 mean value (0.43±0.09 ppm) than the control, which had a mean value of 0.46±0.00 ppm. The mean values in the industrial and urban areas were significantly different (p = 0.001). This study concluded that applying UREA and NPK fertilizers to study area soils lowered the pH of soils in agricultural sites (A1, A2, and A3). Fertilizer use in the study areas increased the population of microorganisms at threshold concentrations but was harmful at concentrations of 1.50 % or higher. Furthermore, findings revealed that microorganisms were more tolerant to fertilizers in agricultural areas (higher LC50 values) than in urban and industrial areas (lower LC50 values). According to the findings of this study, fertilizers used in the study areas were linked to soil microorganisms developing tolerance to NPK and UREA. Farmers should use the recommended amounts of fertilizer to ensure the soil ecosystem's integrity.

scholarly journals Lead and coliform contaminants in groundwater sources in peri-urban areas of Makurdi, Nigeria

2021 ◽  
Vol 19 (3) ◽  
pp. 225-232
Author(s):  
R.A. Agyo ◽  
R.A. Ofukwu ◽  
C.A. Agada ◽  
A.E.J. Okoh
Keyword(s):  
Urban Areas ◽  
Pathogenic Bacteria ◽  
Water Shortage ◽  
Mean Value ◽  
Human Consumption ◽  
Biochemical Tests ◽  
E Coli ◽  
Potable Water Supply ◽  
Populated State ◽  
The Mean

Benue State has one of the most populated state capitals in North-central Nigeria, suffering from acute water shortage despite River Benue that runs through the town. The combined effect of inadequate potable water supply and the polluted nature of the River has pushed the populace, especially peri-urban residents, to resort to water from wells and boreholes. This study investigates the possible contamination by lead, and some waterborne pathogenic bacterial burden of water from wells and boreholes. Four peri-urban areas of Makurdi, Nigeria, were selected for the study. A total of 768 samples were randomly collected, 192 from each location.The presence of lead was quantified using Atomic Absorption Spectrophotometer, while the bacteriological assessment was done using Multiple Tube Fermentation Techniques and biochemical tests. The mean value for lead at the different sampling sites ranged from 0.030 to 0.079mg/L. The mean value of lead in all the wells and locations was significantly (P<0.05) higher than the WHO recommended values of 0.01 mg/L for lead. Five species of pathogenic bacteria were isolated and identified, namely E. coli, Salmonella subsp 3B, Enterobacter pagglomeran complex, Klebsiella pneumoniae and Citrobacter freundii. The mean value for E. coli at the different well types ranged from 0.000 to 0.401 CFUX10 and were significantly (P<0.05) different. Water from wells in Makurdi had high lead concentration as well as enteric pathogenic bacteria that render it not fit for human consumption. It is recommended that regulatory agencies should protect wells through the development of relevant guidelines to address the risk of water contamination.

Long-period modulated superstructures in Pd-12.5 at.%Ce and Pd-15 at.%Ce alloys

1990 ◽  
Vol 48 (4) ◽  
pp. 164-165
Author(s):  
Noriyuki Kuwano ◽  
Masaru Itakura ◽  
Kensuke Oki
Keyword(s):  
Electron Microscopy ◽  
Mean Value ◽  
Heavy Elements ◽  
Arc Furnace ◽  
X Ray ◽  
Long Period ◽  
Ultra High Purity ◽  
Heat Treated ◽  
Atomic Scattering ◽  
The Mean

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.

Partition Coefficient Ratios and Tumour Perfusion Studied with 85mKr and 133Xe

1987 ◽  
Vol 26 (06) ◽  
pp. 253-257
Author(s):  
M. Mäntylä ◽  
J. Perkkiö ◽  
J. Heikkonen
Keyword(s):  
Partition Coefficient ◽  
Partition Coefficients ◽  
Regional Blood Flow ◽  
Blood Perfusion ◽  
Compartmental Analysis ◽  
Malignant Tumour ◽  
Mean Value ◽  
Perfusion Rate ◽  
Biological Variables ◽  
The Mean

The relative partition coefficients of krypton and xenon, and the regional blood flow in 27 superficial malignant tumour nodules in 22 patients with diagnosed tumours were measured using the 85mKr- and 133Xe-clearance method. In order to minimize the effect of biological variables on the measurements the radionuclides were injected simultaneously into the tumour. The distribution of the radiotracers was assumed to be in equilibrium at the beginning of the experiment. The blood perfusion was calculated by fitting a two-exponential function to the measuring points. The mean value of the perfusion rate calculated from the xenon results was 13 ± 10 ml/(100 g-min) [range 3 to 38 ml/(100 g-min)] and from the krypton results 19 ± 11 ml/(100 g-min) [range 5 to 45 ml/(100 g-min)]. These values were obtained, if the partition coefficients are equal to one. The equations obtained by using compartmental analysis were used for the calculation of the relative partition coefficient of krypton and xenon. The partition coefficient of krypton was found to be slightly smaller than that of xenon, which may be due to its smaller molecular weight.

Detection of Soluble Fibrin Monomer Complexes in Blood by Means of Protamine Sulphate Test

1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski
Keyword(s):  
Human Subjects ◽  
Coronary Thrombosis ◽  
Mean Value ◽  
Healthy Human ◽  
Protamine Sulphate ◽  
Soluble Fibrin ◽  
Fibrin Monomer ◽  
Dog Plasma ◽  
The Mean ◽  
Precipitable Protein

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.

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.

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.

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