72 research outputs found
ODABIR NAJPRIKLADNIJEGA NAČINA BUŠENJA I MINIRANJA UPOTREBOM MADM METODA (STUDIJA SLUČAJA: RUDNIK ŽELJEZA SANGAN, IRAN)
Drilling is the first stage of open pit mining that has a considerable effect on the other stages of mining, including blasting, loading, hauling and crushing. An unsuitable drilling pattern may lead to undesirable results such as poor fragmentation, back break and fly rock that not only results in technical and safety issues but also increases the operating cost of the mine. Multi-Attribute Decision-Making (MADM) methods can be useful approaches to select the appropriate drilling pattern among various alternatives, performed previously. This paper aims to select the most proper drilling and blasting pattern for Sangan Iron Mine, Iran. To achieve this, in the first step, rock fragmentation, back break, fly rock, specific charge and specific drilling were considered as the decision criteria and their degree of importance was calculated using the AHP method under a fuzzy environment. Then, TOPSIS and PROMETHEE methods were used to select the most proper alternative. The results of this study show that the drilling pattern with a spacing of 5 m, burden 4 m, hole depth 10 m, and hole diameter 15 cm is the most suitable one. The stemming length and powder factor of the suggested pattern are 2.3 m and 2.6 gr/cm3, respectively.Bušenje je prva faza površinske eksploatacije koja ima znatan utjecaj na ostale faze rudarenja, uključujući miniranje, utovar, transport i drobljenje. Neprimjeren način bušenja može dovesti do nepoželjnih rezultata poput loše fragmentacije, povratnoga loma i odbacivanja stijena, što ne samo da rezultira tehničkim i sigurnosnim problemima, već i povećava operativne troškove rudnika. Metode donošenja odluka s više atributa (MADM) mogu biti korisne za odabir odgovarajućega načina bušenja među raznim prethodno izvedenim alternativama. Cilj je ovoga rada odabrati najpogodniji način bušenja i miniranja za rudnik željeza Sangan, Iran. Da bi se to postiglo, u prvome koraku kao kriteriji za odlučivanje razmatrani su fragmentacija stijena, povratno lomljenje, odbacivanje stijena, specifično punjenje i specifično bušenje, a njihova važnost izračunana je korištenjem AHP metode u neizrazitome okruženju. Zatim su korištene metode TOPSIS i PROMETHEE za odabir najprikladnije alternative. Rezultati ove studije pokazuju da je najprikladniji način bušenja s razmakom od 5 m, opterećenjem od 4 m, dubinom rupe od 10 m i promjerom rupe od 15 cm. Duljina čepa bušotine i specifična potrošnja eksploziva predloženoga uzorka iznose 2,3 m, odnosno 2,6 g/cm3
Scheduling trucks in cross docking systems with temporary storage and dock repeat truck holding pattern using GRASP method
Cross docking play an important role in management of supply chains where items delivered to a warehouse by inbound trucks are directly sorted out, reorganized based on customer demands, routed and loaded into outbound trucks for delivery to customers without virtually keeping them at the warehouse. If any item is held in storage, it is usually for a short time, which is normally less than 24 hours. The proposed model of this paper considers a special case of cross docking where there is temporary storage and uses GRASP technique to solve the resulted problem for some realistic test problems. In our method, we first use some heuristics as initial solutions and then improve the final solution using GRASP method. The preliminary test results indicate that the GRASP method performs better than alternative solution strategies
A comparison of hydroponic and soil-based screening methods to identify salt tolerance in the field in barley
Success in breeding crops for yield and other quantitative traits depends on the use of methods to evaluate genotypes accurately under field conditions. Although many screening criteria have been suggested to distinguish between genotypes for their salt tolerance under controlled environmental conditions, there is a need to test these criteria in the field. In this study, the salt tolerance, ion concentrations, and accumulation of compatible solutes of genotypes of barley with a range of putative salt tolerance were investigated using three growing conditions (hydroponics, soil in pots, and natural saline field). Initially, 60 genotypes of barley were screened for their salt tolerance and uptake of Na+, Cl–, and K+ at 150 mM NaCl and, based on this, a subset of 15 genotypes was selected for testing in pots and in the field. Expression of salt tolerance in saline solution culture was not a reliable indicator of the differences in salt tolerance between barley plants that were evident in saline soil-based comparisons. Significant correlations were observed in the rankings of genotypes on the basis of their grain yield production at a moderately saline field site and their relative shoot growth in pots at ECe 7.2 [Spearman’s rank correlation (rs)=0.79] and ECe 15.3 (rs=0.82) and the crucial parameter of leaf Na+ (rs=0.72) and Cl– (rs=0.82) concentrations at ECe 7.2 dS m−1. This work has established screening procedures that correlated well with grain yield at sites with moderate levels of soil salinity. This study also showed that both salt exclusion and osmotic tolerance are involved in salt tolerance and that the relative importance of these traits may differ with the severity of the salt stress. In soil, ion exclusion tended to be more important at low to moderate levels of stress but osmotic stress became more important at higher stress levels. Salt exclusion coupled with a synthesis of organic solutes were shown to be important components of salt tolerance in the tolerant genotypes and further field tests of these plants under stress conditions will help to verify their potential utility in crop-improvement programmes
Simulation-based optimization approach with scenario-based product sequence in a Reconfigurable Manufacturing System (RMS): A case study
In this study, we consider a production planning and resource allocation problem of a Reconfigurable Manufacturing System (RMS). Four general scenarios are considered for the product arrival sequence. The objective function aims to minimize total completion time of jobs. For a given set of input parameters defined by the market, we want to find the best configuration for the production line with respect to the number of resources and their allocation on workstations. In order to solve the problem, a hybridization approach based on simulation and optimization (Sim-Opt) is proposed. In the simulation phase, a Discrete Event Simulation (DES) model is developed. On the other hand, a simulated annealing (SA) algorithm is developed in Python to optimize the solution. In this approach, the results of the optimization feed the simulation model. On the other side, performance of these solutions are copied from simulation model to the optimization model. The best solution with the best performance can be achieved by this manually cyclic approach. The proposed approach is applied on a real case study from the automotive industry
An imperialist competitive algorithm for a bi-objective parallel machine scheduling problem with load balancing consideration
In this paper, we present a new Imperialist Competitive Algorithm (ICA) to solve a bi-objective unrelated parallel machine scheduling problem where setup times are sequence dependent. The objectives include mean completion time of jobs and mean squares of deviations from machines workload from their averages. The performance of the proposed ICA (PICA) method is examined using some randomly generated data and they are compared with three alternative methods including particle swarm optimization (PSO), original version of imperialist competitive algorithm (OICA) and genetic algorithm (GA) in terms of the objective function values. The preliminary results indicate that the proposed study outperforms other alternative methods. In addition, while OICA performs the worst as alternative solution strategy, PSO and GA seem to perform better
An imperialist competitive algorithm for a bi-objective parallel machine scheduling problem with load balancing consideration
In this paper, we present a new Imperialist Competitive Algorithm (ICA) to solve a bi-objective scheduling of parallel-unrelated machines where setup times are sequence dependent. The objectives include mean completion tasks and mean squares of deviations from machines workload from their averages. The performance of the proposed ICA (PICA) method is examined using some randomly generated data and they are compared with three alternative methods including particle swarm optimization (PSO), original version of imperialist competitive algorithm (OICA) and genetic algorithm (GA) in terms of the objective function values. The preliminary results indicate that the proposed study outperforms other alternative methods. In addition, while OICA performs the worst as alternative solution strategy, PSO and GA seem to perform better
Comparison of cytotoxicity of Miltefosine and its niosomal form on chick embryo model
© 2024 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Various drugs have been used for the treatment of leishmaniasis, but they often have adverse effects on the body's organs. In this study, we aimed to explore the effects of one type of drug, Miltefosine (MIL), and its analogue or modifier, liposomal Miltefosine (NMIL), on several fetal organs using both in silico analysis and practical tests on chicken embryos. Our in silico approach involved predicting the affinities of MIL and NMIL to critical proteins involved in leishmaniasis, including Vascular Endothelial Growth Factor A (VEGF-A), the Kinase insert domain receptor (KDR1), and apoptotic-regulator proteins (Bcl-2-associate). We then validated and supported these predictions through in vivo investigations, analyzing gene expression and pathological changes in angiogenesis and apoptotic mediators in MIL- and NMIL-treated chicken embryos. The results showed that NMIL had a more effective action towards VEGF-A and KDR1 in leishmaniasis, making it a better candidate for potential operative treatment during pregnancy than MIL alone. In vivo, studies also showed that chicken embryos under MIL treatment displayed less vascular mass and more degenerative and apoptotic changes than those treated with NMIL. These results suggest that NMIL could be a better treatment option for leishmaniasis during pregnancy.Peer reviewe
Additive effects of Na+ and Cl– ions on barley growth under salinity stress
Soil salinity affects large areas of the world’s cultivated land, causing significant reductions in crop yield. Despite
the fact that most plants accumulate both sodium (Na+) and chloride (Cl–) ions in high concentrations in their shoot
tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects
of Na+ accumulation. It has previously been suggested that Cl– toxicity may also be an important cause of growth
reduction in barley plants. Here, the extent to which specific ion toxicities of Na+ and Cl– reduce the growth of barley grown in saline soils is shown under varying salinity treatments using four barley genotypes differing in their salt tolerance in solution and soil-based systems. High Na+, Cl–, and NaCl separately reduced the growth of barley, however, the reductions in growth and photosynthesis were greatest under NaCl stress and were mainly additive of the effects of Na+ and Cl– stress. The results demonstrated that Na+ and Cl– exclusion among barley genotypes are independent mechanisms and different genotypes expressed different combinations of the two mechanisms. High concentrations of Na+ reduced K+ and Ca2+ uptake and reduced photosynthesis mainly by reducing stomatal conductance. By comparison, high Cl– concentration reduced photosynthetic capacity due to non-stomatal effects:
there was chlorophyll degradation, and a reduction in the actual quantum yield of PSII electron transport which was
associated with both photochemical quenching and the efficiency of excitation energy capture. The results also
showed that there are fundamental differences in salinity responses between soil and solution culture, and that the
importance of the different mechanisms of salt damage varies according to the system under which the plants were
grown
The inhibitory effect of 6-gingerol and cisplatin on ovarian cancer and antitumor activity: In silico, in vitro, and in vivo
© 2023 Salari, Khosravi, Pourkhandani, Molaakbari, Salarkia, Keyhani, Sharifi, Tavakkoli, Sohbati, Dabiri, Ren and Shafie’ei. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). https://creativecommons.org/licenses/by/4.0/Background: Epithelial ovarian cancer is very common in women and causes hundreds of deaths per year worldwide. Chemotherapy drugs including cisplatin have adverse effects on patients’ health. Complementary treatments and the use of herbal medicines can help improve the performance of medicine. 6-Gingerol is the major pharmacologically active component of ginger. In this study, we compared the effects of 6-gingerol, cisplatin, and their combination in apoptotic and angiogenetic activities in silico, in test tubes, and in in vivo assays against two ovarian cancer cell lines: OVCAR-3 and human umbilical vein endothelial cells (HUVECs). Methods: The drug-treated cell lines were evaluated for their cytotoxicity, cell cycle, and apoptotic and angiogenetic gene expression changes. Results: The proportion of apoptosis treated by 6-gingerol coupled with cisplatin was significantly high. In the evaluation of the cell cycle, the combination therapy also showed a significant promotion of a higher extent of the S sequence. The expression of p53 level, Caspase-8, Bax, and Apaf1 genes was amplified again with combination therapy. Conversely, in both cell lines, the cumulative drug concentrations reduced the expression of VEGF, FLT1, KDR, and Bcl-2 genes. Similarly, in the control group, combination treatment significantly decreased the expression of VEGF, FLT1, KDR, and Bcl-2 genes in comparison to cisplatin alone. Conclusions: The findings of the present study demonstrated that the cisplatin and 6-gingerol combination is more effective in inducing apoptosis and suppressing the angiogenesis of ovarian cancer cells than using each drug alone.Peer reviewe
High concentrations of Na+ and Cl– ions in soil solution have simultaneous detrimental effects on growth of faba bean under salinity stress
Despite the fact that most plants accumulate both sodium (Na+) and chloride (Cl–) ions to high concentration in their shoot tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects of Na+ accumulation. There have also been some recent concerns about the ability of hydroponic systems to predict the responses of plants to salinity in soil. To address these two issues, an experiment was conducted to compare the responses to Na+ and to Cl– separately in comparison with the response to NaCl in a soil-based system using two varieties of faba bean (Vicia faba), that differed in salinity tolerance. The variety Nura is a salt-sensitive variety that accumulates Na+ and Cl– to high concentrations while the line 1487/7 is salt tolerant which accumulates lower concentrations of Na+ and Cl–. Soils were prepared which were treated with Na+ or Cl– by using a combination of different Na+ salts and Cl– salts, respectively, or with NaCl. While this method produced Na+-dominant and Cl–-dominant soils, it unavoidably led to changes in the availability of other anions and cations, but tissue analysis of the plants did not indicate any nutritional deficiencies or toxicities other than those targeted by the salt treatments. The growth, water use, ionic composition, photosynthesis, and chlorophyll fluorescence were measured. Both high Na+ and high Cl– reduced growth of faba bean but plants were more sensitive to Cl– than to Na+. The reductions in growth and photosynthesis were greater under NaCl stress and the effect was mainly additive. An important difference to previous hydroponic studies was that increasing the concentrations of NaCl in the soil increased the concentration of Cl– more than the concentration of Na+. The data showed that salinity caused by high concentrations of NaCl can reduce growth by the accumulation of high concentrations of both Na+ and Cl– simultaneously, but the effects of the two ions may differ. High Cl– concentration reduces the photosynthetic capacity and quantum yield due to chlorophyll degradation which may result from a structural impact of high Cl– concentration on PSII. High Na+ interferes with K+ and Ca2+ nutrition and disturbs efficient stomatal regulation which results in a depression of photosynthesis and growth. These results suggest that the importance of Cl– toxicity as a cause of reductions in growth and yield under salinity stress may have been underestimated
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