77 research outputs found
Recommended from our members
Arbitrage strategy of renewable-based microgrids via peer-to-peer energy-trading
In this paper, an arbitrage strategy is proposed for renewable-based microgrids (MGs) to overcome the volatile behavior of renewable energy sources (RESs) such as photovoltaic and wind in a newly emerged business space in which peer-to-peer (P2P) energy-trading in transactive energy markets (TEMs) set up between a day-ahead market (DAM) and real-time markets (RTMs). To identify arbitrage opportunities created from the price difference between the P2P and real-time trades, a bi-level risk-constrained stochastic programming with interval coefficients (BRSPIC) is presented. In the first stage of the decision-making, scenarios are employed to deal with the DAM prices uncertainties. In the second stage, P2P energy-trading competition is modelled by a bi-level programming based on non-cooperative leader-follower games. While the social welfare of peers is maximized at the lower level, the MG maximizes its profit at the upper level. By getting closer to real-time, interval coefficients are considered in the third stage to cope with the uncertainties of RESs and loads, as well as RTM prices. The conditional value-at-risk (CVaR) is enforced the model to control the risk of profit variability. By using Karush-Kuhn-Tucker (KKT), the BRSPIC is transformed into a single level optimization. Then, it is linearized and solved by a mixed-integer linear programming (MILP) solver. By evaluating the proposed model on a test system, it is evident that the MG increases more than 3.1% of its profit by the arbitrage strategy. By considering CVaR, a fully risk-averse decision decreases the profit of MG by 27%, although it would be so conservative decision
Occurrence and intensity of parasites in Prussian carp, Carassius gibelio from Anzali wetland, southwest Caspian Sea
The aim of this study was to detect the occurrence of parasites in Prussian carp, Carassius gibelio as the most important alien fish in Anzali international wetland. This undesirable fish was introduced accidentally to Iran with Chinese carp fries which imported to the country during the last decades and then acceded to Anzali wetland. Today this fish has significant stocks in Anzali wetland but there have been limited studies about the parasites of this fish in Anzali wetland. During this study a total of 90 Prussian carp were collected by electrofishing and gillnets from April through July 2012. After recording biometric characteristics, common necropsy and parasitology methods were used. A total of 2715 individuals out of 11 parasite species were recovered. Parasitofauna consisted of: two protozoans, Ichthyophthirius multifiliis and Trichodina sp.; one nematode, Raphidascaris acus; one trematode, Diplostomum spathaceum; six monogeneans, Dactylogyrus formosus, Dactylogyrus dulkeiti, Dactylogyrus baueri, Dactylogyrus arquatus, Dactylogyrus inexpectatus and Gyrodactylus kobayashii; and one crustacean, copepodid stage of Lernaea cyprinacea. The monogeneans had the highest prevalence values (88.89%). The occurrence of D. inexpectatus in C. gibelio is reported for the first time in Iran
BQIABC: A new Quantum-Inspired Artificial Bee Colony Algorithm for Binary Optimization Problems
Artificial bee colony (ABC) algorithm is a swarm intelligence optimization algorithm inspired by the intelligent behavior of honey bees when searching for food sources. The various versions of the ABC algorithm have been widely used to solve continuous and discrete optimization problems in different fields. In this paper a new binary version of the ABC algorithm inspired by quantum computing, called binary quantum-inspired artificial bee colony algorithm (BQIABC), is proposed. The BQIABC combines the main structure of ABC with the concepts and principles of quantum computing such as, quantum bit, quantum superposition state and rotation Q-gates strategy to make an algorithm with more exploration ability. The proposed algorithm due to its higher exploration ability can provide a robust tool to solve binary optimization problems. To evaluate the effectiveness of the proposed algorithm, several experiments are conducted on the 0/1 knapsack problem, Max-Ones and Royal-Road functions. The results produced by BQIABC are compared with those of ten state-of-the-art binary optimization algorithms. Comparisons show that BQIABC presents the better results than or similar to other algorithms. The proposed algorithm can be regarded as a promising algorithm to solve binary optimization problems
Comparison of Intelligent Systems, Artificial Neural Networks and Neural Fuzzy Model for Prediction of Gas Hydrate Formation Rate
The main objective of this study was to present a novel approach for predication of gas hydrate formation rate based on the Intelligent Systems. Using a data set including about 470 data obtained from flow tests in a mini-loop apparatus, different predictive models were developed. From the results predicted by these models, it can be pointed out that the developed models can be used as powerful tools for prediction of gas hydrate formation rate with total errors of less than 4%
Effects of temperature on hematological and histopathological changes and survival rate of juvenile Fenneropenaeus vannamei experimentally challenged to White Spot Virus
Many shrimp farmers were suffering from White Spot Disease (WSD) onset in last decades. Oscillation of environmental factors could lead mortality in susceptible hosts. Our study was aimed to investigate the effect of different temperatures on juvenile Fenneropenaeus vannamei experimentally exposed to White Spot Virus (WSV). Five hundred and forty juveniles were distributed among 3 treatments in triplicates, 22, 25 and 30°C and experimentally WSV were injected in the shrimps. Our results showed mortality started at 36 h post inoculation (hpi) in the treatment at 25°C (T25), meanwhile the mean value of mortality percent at 54 hpi in T25 (71.10±17.35) showed the significant difference (p=.045) with T22 (3.33±3.33) and T30 (Not Observed, NO.). Our results suggest that in site selection, in primary stage of farm designing, water temperature at more than 29°C, should be considered as key environmental factor. This finding can lead us that why the White Spot Disease occurred with high mortality in some area when the days of shrimp culture were prolonged until mid autumn
A survey on some risk factors and evaluation of their impacts on streptococcosis in rainbow trout farms in some provinces in Iran (Mazandaran, Fars)
One of the most important bacterial fish diseases which has caused some outbreaks in rainbow trout farms in Iran is streptococcusis. The farmers were suffering from huge economic losses due to the disease outbreaks in different rainbow trout farms in Iran. The aim of our study was to determine rate of streptococcusis incidence in different stage of growth in farmed rainbow trout in Mazandaran and Fars province. Fish and water samples were randomly collected and measured randomly in selected farms, monthly throughout a year. After clinical observations, Isolation and recognition of strep strains were made using biochemical and molecular tests. Some Environmental factors include Nitrate, Nitrite, Temperature, pH, Ammonia and DO measure during sampling periods. According to our results incidence of disease in juvenile is more than growers. Some samples showed clinical signs of streptococcusis without strep. contamination. Main isolated strain were S. iniae and S. garviea and S. uberis recognized for first time in east of Mazandaran province (Haraz River). Incidence of streptococcusis in rainbow trout affected by fluctuation of Nitrite, temperature and DO. Management of these factors can decrease rate of disease outbreaks
Hemocytosis, a new disease in cultured shrimp, Fenneropenaeus indicus
Certain parasites can cause severe diseases in shrimp. Among these, protozoa are very important. The objective of our study was to describe the signs, prevalence, and intensity of hemocytosis, a new disease in shrimp, Fenneropenaeus indicus. The experimental design included three groups, one treatment as infected shrimp or group B and 2 controls with non-infected but exposure to White Spot Syndrome Virus (WSSV) shrimp as group A and non-infected non-exposure to WSSV shrimp as group C in triplicate. The results revealed that Hemocytosis associated with a decrease in hyalinocytes and large-granulocytes (less than 8%) and a considerable increase in semi-granulocytes in group A and B in contrast to group C that Hyalinocyte increased. This infection made the shrimp susceptible to WSSV disease. It is believed that Hemocytosis causes a condition which can result in a rapid mortality among susceptible species, F. indicus when exposure to WSSV is occurred
Adaptation, growth and survival of tilapia (Oreochromis niloticus) in Bafgh brackish water
An experiment was conducted to evaluate the possibility of adaptation, growth and survival of Nile tilapia (Oreochromis niloticus) with 0.3g initial weight and red tilapia (Oreochromis sp.) with 0.7g initial weight in underground brackish water. Fry of Nile tilapia and red tilapia imported from Indonesia and after passing larviculture (25g) were examined separately in fiber glass tank by two replicate. Fish were fed at a restricted feeding program according to standard table during the light period. The results showed that some growth factors such as final weight, final length, daily growth rate, specific growth rate and weight gain in Nile tilapia were slightly higher than red tilapia but other factors such as survival and feed conversion rate in red tilapia were slightly higher than Nile tilapia. There were no significantly differences at 99% level among these factors. Length-weight relationship equation was w = 0.012×TL3.189 in Nile tilapia and w = 0.014×TL3.119 in red tilapia (r2 = 0.99), b value were 3.189 and 3.119 respectively in Nile and red tilapia representing isometric growth. According to the reliable growth and high survival rate (98%), it seems that both Nile and red tilapia could be good candidates for rearing in brackish water condition
Towards minimal models for realistic granular materials: Tomographic analysis of bidispersed assemblies of ellipsoid
In this paper, we report experimental results on granular compaction in a model system made of mono- and bidisperse ellipsoidal packings as well as sand packings with grain size polydispersity. The packings are subject to vertical tapping of varying duration (number of taps) and their internal three-dimensional structure is obtained using x-ray computed tomography. Particles positions and orientations are reconstructed and the global packing densities are computed. The analysis of the vertical and horizontal local packing fraction profiles reveal a homogeneous densification in the ellipsoidal packings, however, sand packings exhibit radial density gradient, possibly linked to the onset of convection
Assessing the sustainability of Litopenaus vannamei on white spot virus vaccine and fed with yeast Sacchromayces cerevisiae and algae Gracilaria corticata in the face of white spot syndrome virus
Efficacy of G. corticata, S. cerevisiae and gamma irradiation WSSV as immunostimulants to white shrimp L. vannamei was investigated. 1200 healthy shrimp SPF L. vannamei subadult with average weight of 10±1.02 g were collected and divided to four groups. The first group (T1) fed with commercial pellet, second group (T2) fed S. cerevisiae (2 g/ Kg), third group (T3) fed G. corticata powder was mixed with shrimp feed (2 g/Kg) and fourth group (T4) fed commercial pellet and injected intramuscularly gamma irradiant WSSV (1µl/gbw). The shrimp were fed on these diets for a period of 10 days and then challenged injected with WSSV and maintained for 25 days. The control group maintained same manner but without inject with WSSV. Survival rate and immune parameters such as total hemocyte count (THC), total protein plasma (TPP), superoxide dismutase (SOD) activity, peroxidase (POD) activity and phenoloxidas activity (PO) were determined. The result indicated survival rate in shrimp group T4 was 57.05±3.52%, shrimp group T3 was 22.5±0.5% and shrimp group T2 was 15±1.05% and shrimp group T1 was 00.0±0%, respectively. The shrimp group T4 showed higher hematological data, i.e. THC, TPP, SOD, POD and PO at the end of experiment. This study showed that gamma irradiant WSSV are effective immunostimulants in shrimp L. vannamei and perform better than the G. corticata and S. cerevisiae
- …