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Load management and cost optimization are among the important factors in trigeneration systems and combined cooling, heating and power (CCHP) systems. In this study, an innovative CCHP system uses a gas turbine as the prime mover and has a heat recovery steam generator (HRSG) in addition to an auxiliary boiler, electric and absorption chillers. The system is tied with the bulk electric grid; to export and sell excess power or import power when necessary. This study analyzes load management and cost optimization of CCHP systems. A heuristic strategy to optimize the total energy cost is then presented. The optimal size of CCHP is determined from the study results. This paper proposes a model... 

The authors regret that there was an error in the SEM image presented in Fig. 4(c) of the previously print version of the article. Please refer to the corrected SEM image as presented here. It is noteworthy that this change does not affect any of the conclusions. The authors would like to apologise for any inconvenience caused. © 2021 Elsevier Ltd  

Maintenance costs in airlines change as time passes. As airplane ages, it needs more often and more expensive checks. Due to these growing expenses, airlines are getting more interested in cost analysis. Under financial pressure, they avoid buying new airplanes and try to maintain the old ones, but sometimes try to cut the maintenance costs by ignoring or delaying some checks. In other words, they are more disposed to spend small amount of money frequently through time, than to spend a great deal on a new airplane with low maintenance costs. Therefore, in such situations, the following questions raise that what solution is more efficient as we look dynamically to the system? For answering... 

Over-the-air (OTA) software download is a key enabling technology for terminal reconfigurations. With increasing the number of network protocols, variety of software products with different software providers and new software threats, it becomes important to download and install assured software on the mobile terminals. Most of the related research works on downloading assured software, focus on software validation after download, and mainly on the terminal. In this paper, a model is proposed in which an Assurance Agency is exploited. This agency is responsible for performing software examination and validations. Unlike related work, examination and validation operations are centrally... 

Today, energy and fresh water play a vital role in human life and the development of economics and also in industry. The energy density in water desalination process is remarkable, so using the renewable energy sources for this purpose can be interesting especially in the high potential renewable energy sources (solar energy) like Middle East. The simulation and feasibility study of solar water desalination system coupled with lithium battery energy storage is considered in the case study of Iran. For these purposes, a complete simulation of the considered system is done. Then, using simulation results, the economic study is carried out using tem economic method. Also, the parametric study... 

Past earthquakes revealed that while fulfilling the requirements of the conventional design codes guarantees the life safety of the occupants, considerable economic losses may still be incurred. This highlights the importance of considering life cycle losses in the design procedure of structures. In this research, the significance of the life cycle seismic risk costs in the optimal design of steel framed tube tall buildings is investigated. Typical 20- and 40-story buildings are optimally designed based on three approaches: the code-based, the cost-based, and the fixed weight approach. The first approach only minimizes the initial cost of the building while in the second and third approaches... 

In this paper, the influence of the excitation angle on the Endurance Time (TCT) analysis of skewed slab-on-girdcr bridges is studied. The excitation of the structure due to the critical angle produces maximum seismic responses that are sometimes significantly higher than the average. The modeled bridges are of slab-on-girder type that are typically used as highway bridges. The bridge models have skew angles of 0, 15, 30, 45, and CO degrees. The ET excitations exerted on structures cover a broad range of hazard levels. The results provide some insight with regard to choosing multiple excitation angles so as to balance computational costs and retain acceptable accuracy for practical design... 

In this paper, the influence of the excitation angle on the Endurance Time (TCT) analysis of skewed slab-on-girdcr bridges is studied. The excitation of the structure due to the critical angle produces maximum seismic responses that are sometimes significantly higher than the average. The modeled bridges are of slab-on-girder type that are typically used as highway bridges. The bridge models have skew angles of 0, 15, 30, 45, and CO degrees. The ET excitations exerted on structures cover a broad range of hazard levels. The results provide some insight with regard to choosing multiple excitation angles so as to balance computational costs and retain acceptable accuracy for practical design... 

In this study, a two-echelon single-vendor supply chain is selected to do a cost-based comparison between short-term performances of a Vendor Managed Inventory (VMI) and a Retailer Managed Inventory (RMI). While the inventory costs include ordering and storing expenses, the rate of consumption and the price of goods are constant, the rate of production and pace of transportation are infinite and shortage is not allowed. This paper, after a comprehensive literature review, is followed by three cases of single retailer, n-retailer and two-retailer chains. Unlike the second case, in the first case, VMI shows an absolute superiority to RMI, and this is the reason for devising the third case in... 

In this paper, the interaction between various window specifications and different climate conditions is investigated. For this purpose, simultaneous effects of several aspects including glazing system, glass type, filling gas, glass thickness, window frame fraction, and interior shading are considered under three different climatic conditions. To evaluate the energy performance of various considered alternatives, the energy simulation of a base case building is evaluated in a computer environment. Using the validated model, the energy analysis is quantitatively performed, and cost-benefit analyses from the viewpoints of both residents and government are carried out based on the domestic and... 

The Social Cost of nuisance noise from a wind turbine is defined here as the additional cost to reduce the noise level at a receptor to an exceptable, non-nuisance value, i.e. to mitigate this cost. This acceptable sound level is considered to be 35 dB. Our example is a 10-kW (nominal power) wind turbine considered to supply the electrical energy needs of a 3-storey residential building in Tehran and Manjil. The turbine generates sound at 75 dB. To reduce the sound level at the third floor of the building to 35 dB, it was necessary to increase the height of the turbine from 24 m to 48 m. The initial installed cost of the turbine thereby increased from US$45.000 to US$55,000. The cost of... 

In recent years, the management of health systems is a main concern of governments and decision-makers. Home health care is one of the newest methods of providing services to patients in developed societies that can respond to the individual lifestyle of the modern age and the increase of life expectancy. The home health care routing and scheduling problem is a generalized version of the vehicle routing problem, which is extended to a complex problem by adding special features and constraints of health care problems. In this problem, there are multiple stakeholders, such as nurses, for which an increase in their satisfaction level is very important. In this study, a mathematical model is...