SMSE: A serverless platform for multimedia cloud systems

Along with the rise of domain-specific computing (ASICs hardware) and domain-specific programming languages, we envision that the next step is the emergence of domain-specific cloud platforms. Considering multimedia streaming as one of the most trendy applications in the IT industry, the goal of this study is to develop serverless multimedia streaming engine (SMSE), the first domain-specific serverless platform for multimedia streaming. SMSE democratizes multimedia service development via enabling content providers (or even end-users) to rapidly develop their desired functionalities on their multimedia contents. Upon developing SMSE, the next goal of this study is to deal with its efficiency challenges and develop a function container provisioning method that can efficiently utilize cloud resources and improve the users' quality of service. In particular, we develop a dynamic method that provisions durable or ephemeral containers depending on the spatiotemporal and data-dependency characteristics of the functions. Evaluating the prototype implementation of SMSE under real-world settings demonstrates its capability to reduce both the containerization overhead, and the makespan time of serving multimedia processing functions (by up to 30%) in compare to the function provision methods that are being used in the general-purpose serverless cloud systems.     

通过双级固溶热处理制备新型高强Al−10.5Si−3.4Cu−0.2Mg合金

通过析出硬化提高Al?Si?Cu合金的力学性能.这些合金对时效硬化的反应非常缓慢.为了解决这一问题,在Al?10.5Si?3.4Cu合金中分别加入0.2％、0.4％和0.7％(质量分数)的镁.该新型合金在固溶处理阶段经过两种不同的析出硬化过程.结果表明,添加不同含量的镁可加速该合金对时效处理的响应,提高其硬度和强度.双...     

Retracted papers by Iranian authors: causes,journals, time lags,affiliations, collaborations

Scientometrics - This study aims to analyze 343 retraction notices indexed in the Scopus database, published in 2001–2019, related to scientific articles (co-)written by at least one author...     

A primary unit commitment approach with a modification process

This paper introduces an approach to one of the most important problems in electrical power system called the Unit Commitment (UC). The proposed method PUC-MP which stands for the primary unit commitment-modification process, addresses this problem firstly by using a simple and new priority for operating the generating units in each hour, and then, using a modification process which enhances the solution quality with lower cost. The PUC-MP takes advantage of both deterministic and stochastic algorithms in its structure to solve the discrete-variable part of the UC problem for choosing a suitable combination of units in each hour, and also, continuous-variable part of it which is dispatching the operating units’ output power to the power network load economically. The latter part which is called economic dispatch (ED) has been solved using an intelligent algorithm which in turn has been customized by two new ideas to increase its efficiency. Simulation results show that this new approach even without using its modification process can be considered as an effective approach which surpasses some other popular and recently reported methods in producing near-optimal and robust solutions.     

A356 Reinforced with Nanoparticles: Numerical Analysis of Mechanical Properties

Commercial casting Al-Si (A356)-based composites reinforced with different volume fractions of alumina (Al₂O₃) nanoparticulates (average particle size 50 nm) were synthesized in this study. Particle distribution, hardness, and tensile properties in the as-cast condition were experimentally investigated. The A356 alloy composite showed an increase in hardness, elastic modulus, and tensile strength compared with monolithic alloys. Finally, a combination of an artificial neural network and the finite element method (FEM) was implemented to predict the microstructure and mechanical properties including grain size, length of silicon rods, amount of porosity, hardness, tensile yield stress, ultimate tensile stress, and elongation percentage.     

Superior Tribological Properties of Particulate Aluminum Matrix Nano Composites

Aluminum is the best metal for producing metal matrix composites which are known as one of the most useful and high-tech composites in our world. Combining aluminum and nano Al₂O₃ particles will yield a material with high mechanical properties. Characterization of tribological properties revealed that the presence of nano particles significantly increased wear resistance of the composite. In case of unreinforced Al alloy, the depth of penetration is governed by the hardness of the specimen surface and applied load. But, in case of Al matrix composite, the depth of penetration of the harder asperities of hardened steel disk is primarily governed by the protruded hard ceramic reinforcement. The hard Al₂O₃ particles act as a protrusion over the matrix, carries a major portion of the applied load and protect the abrasives from penetration into the specimen surface.     

Energy use efficiency and economical analysis of almond production: a case study in Chaharmahal-Va-Bakhtiari province,Iran

The aim of this study was to analyse input–output energy and economical assessment of almond production in three age groups of orchards (group I 6–10, group II 11–15 and group III 16–20 years old) in Chahrmahal-Va-Bakhtiari province, Iran. Data for almond production were collected by administering questionnaire in face-to-face interviews from the orchards selected based on random sampling method during a 3-year period. The results showed that 57,027.13, 60,341.14 and 61,640.43 MJ ha^?1 energy was consumed by group I, group II and group III, respectively. The most energy input was consumed by electricity, followed by chemical fertilizer. Energy indices were calculated, and the results revealed that energy efficiency was 0.62, 1.12 and 0.81 in the triple groups of orchards, respectively. Economical assessment showed that total production cost of almond in group I, II and III was $4547.54, $5799.26 and $5687.05 ha^?1, respectively. In all orchard groups, the shares of variable and fixed production costs found to be same nearly. Net return for almond production was $14,516.22, $30,735.19 and $21,395.57ha^?1, respectively. According to the research results, it was concluded that although almond production in the study region was not an efficient process in terms of energy consumption, it was a profitable agricultural operation.