Drones, or Unmanned Aerial Vehicles (UAVs), are among the most beneficial and emerging technologies, with a wide range of applications that can support the sustainability concerns of smart cities and ultimately improve citizens' quality of life. The goals of this systematic review were to explore the involvement of surveillance drones in smart cities in terms of application status, application areas, proposed models, and characteristics of drones. We conducted this systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched the Web of Science and Scopus for journal articles and conference papers written in English and published up to August 2021. Of the 323 records identified, 43 met the inclusion criteria. Findings showed that surveillance drones were used in seven distinct research fields (transportation, environment, infrastructure, object or people detection, disaster management, data collection, and other applications). Air pollution and traffic monitoring were the dominant application areas. The majority of reviewed models were based on the application of rotary-wing single-drones with the camera as the aerial sensor. Reviewed models showed that the adoption of a single or multiple UAVs, either as a stand-alone technology or integrated with other technologies (e.g., internet of things, wireless sensor networks, convolutional neural networks, artificial intelligence, machine learning, computer vision, cloud computing, web applications), can offer efficient and sustainable solutions compared to conventional surveillance methods. This review can benefit academic researchers and practitioners.

No abstract

No abstract

A small portion of oil can be extracted during primary and secondary stages of oil production, and significant quantities of oil remain in reservoirs. Enhanced oil recovery methods are used to extract the trapped oil with high viscosity in reservoirs and improve the efficiency of the production wells. Ultrasonic-based enhanced oil recovery method has become of considerable interest to researchers in recent years. This paper mainly presents the in-depth literature review of ultrasonic wave to investigate its application development trend in enhanced oil recovery. Besides, it also presents an overview of conventional enhanced oil recovery techniques such as chemical, gas, and thermal methods and nonconventional techniques such as electromagnetic and microwave heating. The results exhibit an increasing implementation of the ultrasonic waves for oil recovery since it is an inexpensive and ecologically sound method, can be applied in any type of reservoir, protects the well against damage, prevents heat loss, and enables stimulation freely.

No abstract

No abstract

One of the most important criteria in freight modal choices is the transport operating cost in which fuel price changes has a significant effect on it. This paper presents the impact of fuel price increases on the operating cost of the different transport modes for the containerized freight transportation. In this study, an operating cost equation was applied to compare the operating cost of different freight transport vehicles as well as evaluation of the operating cost changes across a range of fuel prices between the current price and one-hundred percent increase. The equation consists of influential parameters such as fuel cost, driver wage and maintenance cost of a vehicle. It has been concluded that the effect of the fuel price increase on the operating cost of different freight transportation modes is not in the same rate. According to equation and effective parameters considered, comparing the results showed that truck has the highest cost, train has the largest increase in price. Finally, the ship is the most influenced vehicle in terms of operating cost percentage increase when the rate of fuel price increase, followed by train and truck.

No abstract