Load balancing in cloud data centers with optimized virtual machines placement

So far, various solutions have been proposed for symmetric distribution of load cloud computing environments. In this article, a new solution to the optimal allocation of virtual machines in the cloud data centers is presented to provide a good load balancing among servers. The proposed method offers a solution uses learning automata as a reinforcement learning model to improve the performance of the optimization algorithm for optimal placement of virtual machines. Also, it helps the search algorithm to converge more quickly to the global optimum. The simulation results show the proposed method has been able to perform good level of load balancing in cloud data centers

Reducing energy consumption of cloud data centers using proper placement of virtual machines

In today's world, the use of cloud data centers for easy access to data and processing resources is expanding rapidly. Rapid technology growth and increasing number of users make hardware and software architectures upgrade a constant need. The necessary infrastructure to implement this architecture is the use of virtual machines in physical systems. The main issue in this architecture is how to allocate virtual machines to physical machines on the network. In this paper we have proposed a method to use virtualization for minimizing energy consumption and decreasing the cloud resource waste. We have used learning automata as a reinforcement learning model for optimal placement of virtual machines. The simulation results show the proposed method has good performance in reducing energy consumption of servers in cloud data centers.Comment: arXiv admin note: substantial text overlap with arXiv:2311.1614

Cocos Frillgoby, Bathygobius cocosensis (Bleeker, 1854): an additional fish element for the Iranian marine waters (Teleostei: Gobiidae)

Members of the pantropical/subtropical genus Bathygobius are small and common gobies in sheltered and exposed shallow rocky or sandy shorelines, reef crests, mangroves, seagrass beds, rock jetties and seawalls in the Atlantic and Indo-Pacific regions. This report documents a significant range extension of Cocos Frillgoby, Bathygobius cocosensis into the western parts of Indo-Pacific regions, in the Iranian intertidal coast of Makran Sea. The morphological description of collected individuals and its comparison with morphologically similar related goby species, B. meggitti is given and discussed

Qanat system, an ancient water management system in Iran: History, architectural design and fish diversity

Ancient Iran is one of the leading civilizations that actively appear to water resources management, especially by the invention of "Qanat", an artificial underground system/ subterranean tunnel-wells system where the water flows through gravity on a slight slope in arid and semi-arid regions at least 5000 years ago. Qanats were innovated in ancient Iran, spread throughout much of the Middle East, and extended into North Africa, Spain, Italy, and South Asia. Tools preparation, size selection, digging the first and deepest vertical shaft known as "mother-well", digging several other vertical shafts along a line between the mother-well and Qanat outlet, and constructing a horizontal connection between vertical shafts (known as the main tunnel), which guides the water out through an outlet, are the main steps in Qanat construction. By this innovation, Iranian solved their water-related problems using the basic concepts of Hydraulics. In the same way, water-related infrastructures were built using locally available materials to make a better life for humans and other wonderful well-designed and well-adapted organisms in dry and semi-dry regions, yielding great civilization with a simple, but a fantastic architecture that provides cold water in hot summer and warm water in cold winter. By means of these ancient underground structures, water was funneled from mountainous areas and aquifers to lower lands and thus alluvial fans could be opened up to settlement, and an agrarian civilization developed and evolved. In addition, Qanat provides a continual flow suitable for many aquatic organisms, including crabs, amphipods (gamarids), freshwater shrimps, and fishes. Qantas are home and refugia to about 42 fish species (36 native and 6 exotic species) belonging to 20 genera, 7 families, and 2 orders. The Qanat ichthyofauna is dominated by Cyprinidae with 19 species (45.2 %) followed by Leuciscidae and Nemacheilidae (6 species, 14.28% each), Poeciliidae and Aphaniidae (4 species, 9.52%), and Cobitidae (1 species 2.38%). It is about 14% of the total ichthyofauna of Iran. The Qanat ichthyofauna comprises 36 natives (including 20 endemics) and 6 exotic species. Qanat fauna dominates by species that are generally of small size, are broadcast spawners, nonmigratory, and have a wide tolerance of environmental conditions

UGROŽENE VRSTE RIBA U SVIJETU: Aphanius farsicus Teimori, Esmaeili i Reichenbacher, 2011 (Cyprinodontidae)

Tooth-carp Aphanius farsicus Teimori, Esmaeili and Reichenbacher, 2011 (Cyprinodontidae), or Farsi endemic tooth-carp, was once common in the Maharloo Lake Basin (Fars), but is disappearing now from its native region. This fish has not been listed in IUCN Red Data Book even though it should be due to criteria such as restricted distribution, destruction of spawning grounds and environmental pollution and drought. This vulnerable species has considerable ecological importance, but there are little data on its biology. The limited available data on its systematics, distribution, ecology, reproduction and threats are summarized and discussed.Vrsta šaranozupke Aphanius farsicus Teimori (Esmaeili i Reichenbacher, 2011) iz porodice Cyprinodontidae ili endemična farska vrsta nekoć je bila česta u slivu jezera Maharloo, a danas nestaje iz autohtonog staništa. Ova vrsta šaranozupke još se ne nalazi na popisu IUCN-ove Crvene knjige ugroženih vrsta, iako zadovoljava sve kriterije za svrstavanje na spomenuti popis – ograničena joj je distribucija, mrijestilišna područja se razaraju, zagađuje se okoliš i javlja se suša. Ova osjetljiva vrsta ima veliku ekološku važnost, ali postoji malo podataka o njezinoj biologiji. U ovom članku iznose se i analiziraju ograničeni dostupni podaci o njezinoj sistematici, distribuciji, ekologiji, reprodukciji i prijetnjama koje joj ugrožavaju stanište

Gonad morphology and histology of an endemic tooth-carp, Aphanius sophiae (Heckel, 1847) from Iran

This study presents the first details on morphological and histological characteristics of gonads and gonadal development stages of an endemic tooth-carp, Aphanius sophiae (Heckel, 1847) from a spring-stream system (south of Iran). The sampling was done from March 2012 to March 2013 using dip net, and a total of 226 individuals were collected. The gonads of specimens were removed, and then fixed in 10% formalin solution after checking their morphology and measuring their weights, lengths and widths. Based on the size, shape and weight of the gonads, degree of occupation of the body cavity, presence or absence of ripe oocytes or milt, diameter of the oocytes in the ovary, and histological observations, five stages of sexual maturation in females and males were determined by macroscopic and microscopic criteria. The results of the gonadal stages indicated that A. sophiae spawns at the beginning of spring

Food and feeding habits of silver carp, Hypophthalmichthys molitrix (Val., 1844) in Gobindsagar Reservoir, India.

Investigation on the food and feeding habits of silver carp in Gobindsgar reservoir indicated that the diet of silver carp was dominated by Cyclotella spp. (diatom) followed by Chlorophyceae, Cyanophyceae, Crustacea, Dianophyceae and Rotifera. The size range of Cyclotella spp. varied between 5-25 µm indicating that silver carp is capable to collect the food particles smaller than distance between its gill rakers. Probably, excretion of mucus plays an important role in collecting such small particles. By applying Costello method, it was concluded that Cyclotella spp. is very important food item while the others are general food items in the diet of silver carp in this water body. Study of diet overlap index of different size groups revealed that the value of “D” varied between 0.461 (moderate) to 0.972 (high), indicating that the diet of small size groups was significantly different from those of large size groups. The present observations indicated that the diet overlap index between female and male silver carp was very high (0.915), clearly indicating that the diet of male and females specimens did not differ significantly. Analysis of gut contents of silver carp indicated that zooplankton comprised only 7.7% by number and 19.3% by volume in the fore–gut contents of this fish, hence, silver carp can be considered as microphytoplankton feeder

Morpho-histological characteristics of gonads and reproductive index in an endemic fish species, Oxynoemacheilus persa (Heckel, 1847) (Teleostei: Nemacheilidae) from Kor River

This study presents the first details on morphological and histological characteristics of gonads, gonadal development stages and reproductive index of the Persian loach, Oxynoemacheilus persa (Heckel, 1847), an Iranian endemic species. Sampling was done from April 2010 to April 2011 using electrofishing device and a total of 196 individuals were collected. The gonads of specimens were removed, their sexes determined and then were fixed in 10% formalin solution after checking their morphology and measuring their weights, lengths and widths. Based on the size, shape and weight of the gonads, degree of occupation of the body cavity, presence or absence of ripe oocytes or milt, diameter of the oocytes in the ovary, and histological observations, five stages of sexual maturation in females and four stages in males were determined by macroscopic and microscopic criteria. The results of the gonadal stages showed that the O. persa spawns in the middle of spring and these stages were correlated to the gonado-somatic index (GSI)

Population dynamic parameters of the highly endemic fish, Alburnoides qanati Coad and Bogustkaya 2009, (Teleostei: Cyprinidae) in the Kor River Basin, Iran

The present study provides the data on the population parameters of an endemic qanat spirlin, Alburnoides qanati from the endorheic Kor River basin of Iran to assess the stock status of this cyprinid fish species, which is highly important from management and conservation points of views. Fish specimens (387) were collected from Moshkan Stream, Kor River basin, Iran in 2011-2012. Asymptotic length (L∞) and growth coefficient (K) were estimated at 123.9 mm and 0.31/year for females and 93 mm and 0.49/year for males, respectively. Growth performance index (Ø') was calculated as 8.47 and 8.35 for female and male specimens, respectively. Total mortality (Z) of females (1.56/year) was higher than males (1.14/year) whereas natural mortality (M) of female specimens (0.44/year) was lower than male specimens (0.65/year). Data on growth and mortality parameters and also length-weight relationship of A. qanati revealed significant differences with corresponding data from other Alburnoides species from Iran and other countries, which could be attributed to habitat’s differences and specific species characteristics