Evolutionary Structural Optimization Using the Minor Value of Material Efficiency

2014 ◽  
Vol 945-949 ◽  
pp. 1223-1226
Author(s):  
Xing Guo Hu ◽  
He Ming Cheng

In the tradition Evolutionary Structural Optimization (ESO), the maximum value of inefficient material efficiency equates to the product of the rejection rate and the maximum value of all material efficiency. However, the rejection rate cannot be adjusted flexibly according to the trend of optimization, and the maximum value of all material efficiency may mutate abruptly (become larger or smaller). These two factors may cause that material may sometimes be removed less, sometimes too much. In view of the defect of the traditional evolutionary structural optimization, the Evolutionary Structural Optimization Using the Minor Value of Material Efficiency (ESO-MVME) is proposed in this paper. The maximum value of the inefficient material is close to the minimum value of material efficiency, and has nothing to do with the reject rate and the maximum value of material efficiency. The study finds that the ESO-MVME method has a better applicability than the traditional ESO, and can obtain a better optimization result.

2013 ◽  
Vol 482 ◽  
pp. 317-321 ◽  
Author(s):  
Xing Guo Hu ◽  
He Ming Cheng

In the evolutionary structural optimization (ESO) using the rejection ratio, the criterion of the inefficient material removal cant generally be lowered during the optimization process because the rejection ratio cant be decreased. Owing to this, some sorts of structures in special load cases cannot be optimized smoothly; or the late optimization of an ordinary structure is terminated suddenly when the removal of material abruptly increases excessively. The paper puts forward the Evolutionary Structural Optimization using Material Efficiency Grades (ESO-MEG) in order to eliminate the unfavorable effects of the rejection ratio on the results of ESO. The ESO-MEG can determine inefficient material in a structural optimization according to the efficiency grades of each part of material, so it can adjust timely and flexibly the criterion of inefficient material removal. The research shows that the ESO-MEG is applicable to the optimization of different sorts of structures in varying sorts of load cases, so generalization of this method has a broad prospect.


2020 ◽  
Vol 7 (04) ◽  
Author(s):  
SATYA NARAYAN SINGH ◽  
RAJESH G BURBADE ◽  
HITESH SANCHAVAT ◽  
P S PANDIT

The cereals of today are more nutritious and healthful than ever before. Cereals processing is one of the oldest and the most essential part of all food technologies. Pasta products and noodles have been staple foods since ancient times in many countries all over the world. In this study pasta formulation was substituted with blending sapota powder in different proportions (4 levels i.e. 0%, 10%, 20%, 30%) into semolina and maida flour separately. Pasta products were prepared using eight different formulations and adding water (approximately 31% of total weight) in DOLLY pasta extruder machine. All the samples were evaluated for physical properties: specific length (mm/g), bulk density (kg/m3), specific density (kg/m3) and porosity (%); functional properties: water absorption index (%), water solubility index (%) and oil absorption capacity (ml/g) and nutritional compositions: moisture (%), crude protein (%), fat (%) and carbohydrate (%). Highest specific length 36.20 mm/g was observed for T5 treatment, low bulk density 368.10 kg/m3 was observed for T5 and highest porosity 9.24% was found for T1 treatment. The maximum WAI, WSI values 325.83%, 17.33% respectively was observed for T1 treatment and minimum value of oil absorption capacity 1.06 ml/g for T8 treatment. The moisture content of dried pasta products was found in the range of 6 to 7%. The maximum value of crude protein 13.07% was found for T5 and minimum value 8.81% for T4 treatments. The fat contents were varied from 1.02% to 1.28 %. The maximum value of carbohydrate was 76.20% for T1 and minimum value 65.41% for T8.


Author(s):  
A. Usman ◽  
B. B. Ibrahim ◽  
L. A. Sunmonu

Characteristic variation of ground heat flux and net radiation enhances the understanding of the significance of indicated trends of variability to everyday life and factors that might be responsible for such variations. This research work critically analyses some specific days with field data over grass-covered surface at Ile-Ife, Nigeria between ground heat flux and net radiation. For the field observations, an instrumented meteorological mast was set up at an experimental site (7°33’N, 4°35’E) located at Obafemi Awolowo University campus, Ile-Ife, Nigeria for a period of two weeks (31st May-14th June, 2013). The soil heat flux, net radiation and soil temperature from the soil heat flux plate; an all-wave net radiometer, and soil thermometer were recorded every 10 seconds and averaged over 2 minutes interval. The sampled data was stored in the data logger (Campbell Scientific, Model CR10X) storage module. After the removal of spurious measurement values (Quality Assurance and Quality Control), the data stored was further reduced to 30 minutes averages using the Microcal Origin (version 7.0) data analysis software. The results showed that the measured ground heat flux, HGM during the daytime increases until 1400 hrs with maximum value of about 136.86 Wm-2 and minimum value of about -72.87 Wm-2 at 0830 hrs (DOY 156). The measured net radiation, Rn value of 649.65 Wm-2 observed at 1400 hrs (DOY 156), represented the maximum value for the entire period of the study. -10.75 Wm-2 value observed at1800 hrs (DOY 154), represented the minimum value for the entire period of the study due to the cloudy condition of the sky which reduces the amount of incoming solar radiation reaching the earth surface.


2018 ◽  
Vol 6 (6) ◽  
pp. 453-460
Author(s):  
Chijioke C ◽  
Nwaiwu ◽  
Aginam ◽  
Anyadiegwu

This work focuses on the 100% replacement of river sand with quarry dust in the production of concrete. Two types of concrete were produced (concrete made with river sand and that made with quarry dust as fine aggregate), the concretes produces were cast into beams and cured for 28 days. The flexural strengths of the concrete beams cast was determine at 28 day strength. At 28 days target strength the maximum flexural strength of concrete made with river sand as fine aggregate is 5.375111N/mm2 and minimum flexural strength is 2.2155N/mm2, for the concrete made with quarry dust as fine aggregate the maximum flexural strength is 2.567 N/mm2. The maximum value of 2.567 N/mm2 for concrete made with quarry dust as fine aggregate is higher than the minimum value of 2.2155N/mm2 for concrete made with river sand as fine aggregate. With this result it shows that quarry dust is a good substitute to river sand in the production of concrete.


2017 ◽  
Vol 53 (3) ◽  
pp. 191
Author(s):  
Soetrisno Soetrisno ◽  
Isharyadi Isharyadi ◽  
Sri Sulistyowati

Preeclampsia is a multifactorial syndrome in pregnancy whose cause is still unknown. Several proangiogenic and antiangiogenic mediators such as Vascular Endothelial Growth Factor (VEGF) and Nitrite Oxide (NO) play important roles in preventing preeclampsia. VEGF can increase NO level that lowers maternal blood pressure, improves endothelial function and reduces placental hypoxia in preeclampsia. Recombinant VEGF 121 is expected to be an option in the prevention and treatment of preeclampsia. This experimental study used mice (Mus musculus) as the model. The objective of this study was to observe the effect of recombinant VEGF 121 in increasing the level of nitric oxide in mice (Mus musculus) model of preeclampsia. This was an experimental analytical study with Randomized Control Trial (RCT) design. The study enrolled 27 pregnant mice (Mus musculus) which met the restriction criteria divided into 3 groups. The first group (K1) were 9 normal pregnant mice. The second group (K2) were 9 pregnant mice of preeclampsia model without treatment. The third group (K3) were 9 pregnant mice of preeclampsia model receiving recombinant VEGF 121 therapy. The independent variable was the administration of recombinant VEGF 121 and the dependent variable was the serum NO level. Statistical analysis was performed by using anova statistics. NO level in the first group (K1) was 1.746±0.347, with minimum value of 1.00 µM, and maximum value of 2.28 µM, CI (1.479-2.013).  NO level in second group (K2) was 1.167±0.380, with minimum value of 0.64 µM, and maximum value of 1.94 µM, CI (0.875-1.460). NO level in the third group (K3) was 2.164±0.556, with minimum value of 1.56 µM, and maximum value of 5.96 µM, CI (1.842-2.486). With anova statistical test, there were significant differences between K1 group and K2 group (p value=0.004<0.05), K1 group and K3 group (p value=0.000<0.05) as well as K2 group and K3 group (p value=0.029<0.05). In conclusion, Recombinant VEGF 121 increased the level of nitric oxide in mice (Mus musculus) model of preeclampsia significantly.


2012 ◽  
Vol 204-208 ◽  
pp. 4422-4428
Author(s):  
Da Ke Zhang ◽  
Wen Pan Zhang ◽  
Han He ◽  
Chong Wang

The efficiency of the element removal or addition is of significance for evolutionary structural optimization (ESO) process. The key is to find an appropriate rejection criterion (RC) which allows to assess the contribution of each element to the specified behavior(stress, stiffness, displacement, etc.)of the structure, and to subsequently remove elements with least contribution. This paper proposed a varying elements removal ratio (VERR) method which uses a larger ERR (Element Rejection Ratio) value at early iterations where exist a lot of redundant material, and decreases the value of ERR in the optimal process to lessen the number of elements removed at later iterations. Meanwhile, this paper proposed a strategy for element addition based on stress level and the contribution of elements to the structure in order to decide which elements should be added to the model and the sequence of the element addition. With the proposed VERR and the strategy, the optimization procedure of the structure evolves more quickly and smoothly.


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