Convective heat transfer induced in open cavities is one of the main pillars that the topic of energy saving relies on. This article reviews and categorizes the results of researches on mixed convection in open cavity connected with a channel and highlights the gap that should be filled in future works. It is found that the best heat and mass transfer is attained when the source of heat and/or species is located at a vertical wall of the cavity where it opposites the flow direction. The review has revealed that the experimental studies are relatively scare where it 10% of the total reviewed studies, while those dealing with nanofluids and porous media are 9% for each. It is found that the process of injection or aspiration of the flow have received very few studies despite its promised improvement of the heat and mass transfer. Furthermore, few researches have studied the contamination removing from the cavity.

This paper provides multiband antenna-based Metamaterial for gains improvement. Here, the developed antenna constitutes patches such that the first is square-shaped and printed on a Taconic FR-30 substrate. In addition, for exciting the first patch, the process used conduction, whereas the other was capacitively coupled to the source as the impedance of either should be matched accordingly. Furthermore, the second patch constitutes a metasurface layer designed and placed on it as a superstrate, which increases the antenna gain towards the CRLH. The results show a maximum gain of 14.5 dBi at 5.7 GHz with maximum dimensions of 200x 200mm2. Moreover, this antenna operates at additional frequency bands (1.1 GHz, 1.3 GHz, 1.7 GHz, 3 GHz, 3.1GHz,3.4 GHz,4.7 GHz,4.9 GHz,5.7 GHz and 5.9 GHz), with a minimum reflection coefficient of -18.2db,-11.75db, -11.52db, -20.3db -17.47dB,-14.27dB,-11.3dB,-13.9dB -10.16dB and,-14.69dB respectively. The proposed antenna is designed and analyzed using the CST MWS simulator.

This paper presents a novel, compact, and high gain metasurface (MS) patch antenna. The antenna structure consists of a slotted square patch in a fractal shape, integrated with a metasurface layer stacked on Taconic RF-30 dielectric material. The individual cells are arranged periodically, creating a 5 x 5-layer configuration. The proposed antenna is designed with physical dimensions of 290 x 290 mm² and achieves a maximum gain of 13.3 dBi at a frequency of 2.2 GHz. Moreover, it achieves a satisfactory minimum reflection coefficient of -10.9 dB. The design process and analysis were performed using the CST MWS simulation software. Based on the performance results obtained from this study, the suggested antenna can be considered suitable for applications in 5G communication.

This paper describes a flexible and frequencyreconfigurable antenna with a unique structure that suppresses interference for multiple wireless applications. The antenna design is based on a square shape with etched slots and utilizes pin diodes to achieve frequency reconfigurability by connecting and disconnecting the stubs and the rectangular patch. The antenna is designed on a conformal substrate. It resonates at five different reconfigurable bands (1.4GHz, 2.1GHz, 2.3GHz, 2.5GHz, 4.6GHz, 5GHz, 5.6GHz, 6GHz) that are commonly used for 5G sub-6 GHz. Simulated results demonstrate excellent performance in impedance matching, controllable resonant bands, and high gain (>10 dBi). The antenna exhibits consistent radiation patterns and achieves an efficiency of over 88%. Additionally, conformal analysis indicates that the antenna maintains its performance in both flat and bending conditions, rendering it suitable for flexible electronics. Furthermore, the antenna is compared with state-of-the-art works in similar applications to demonstrate its potential across targeted band spectrums.

In this paper, the thin-film ferroelectric material equation (TFFME) which enables the propagation of solitary polarization in thin-film ferroelectric materials is investigated, and also illustrated through the nonlinear evolution equations. Ferroelectrics are dielectric materials that exhibit nonlinear behaviors in wave propagation. Thin films constructed from the ferroelectric materials are utilized in different modern electronic devices. To investigate the characteristics of new waves, the solitary wave dynamics of the mentioned equation is used in the generalized trial equation scheme. The bright and periodic solutions are obtained by semi-inverse variational principle scheme. Many alternative responses may be obtained through different formulae; each of these solutions offers a distinct graph. The validity of such methods and solutions may be demonstrated by assessing how well the relevant techniques and solutions match up. The effects of free variables on the behavior of few achieved solutions for nonlinear rational exact cases are also plotted and explored depending upon the nature of nonlinearities. The dynamic properties of the obtained results are shown and analyzed by some density, two- and three-dimensional images. The results provide a way for future research on generating optical memories based on the nonlinear solitons.

This paper presents a new design and analysis of a reconfigurable antenna with a switchable slot held using PIN diodes for multifunction reconfiguration, including frequency multiplexing. The performance of the proposed antenna in terms of reflection coefficient spectra and radiation patterns is evaluated. From the results obtained, it is observed that the antenna can be operated for different frequencies: 1.8 GHz, 2.7 GHz, 3.1 GHz, 3.3 GHz, 4.1 GHz, 5.1 GHz, and 5.4 GHz. A maximum gain of 11.1 dBi is also significantly achieved at 5.1 GHz. Moreover, this antenna is designed to provide a high Q-factor and low-frequency ratio (FR) for using the spectrum efficiently. Upon the advantage of spatial diversity, multiple independent data streams can be transmitted over the same frequency simultaneously. All results obtained in this work were produced based on the simulation process using CST Microwave Studio simulator software at different switching scenarios.

This research suggests a multiband antenna-based Metasurface for improved gains and beam splitting. Here, the development of a smart antenna for contemporary wireless applications through the use of a Metasurface technology is the main goal. The initial patch of the proposed antenna is square in shape and is positioned on Taconic substrate. The suggested patch appears to be U-shaped at the end of the design process to guarantee that the antenna beam is splitting at the intended frequency ranges. Furthermore, the first patch is excited by conduction using a 50 Omega discrete port, whereas the second patch is excited via capacitive coupling. Moreover, to boost the antenna gain in the bore-sight direction, a metasurface layer is created and affixed to the second patch as a superstrate. The outcomes indicate a maximum gain. The results indicate a maximum size of 280x 280mm2 and a maximum gain of 8 dBi at 4.2 GHz. Furthermore, this antenna has a minimum reflection coefficient of -18.5 dB, 11.1 dB, -25.2 dB, -25.2 dB, -17.4 dB, and -11.5 dB, respectively, and operates at additional frequency bands (1.9 GHz, 3.3 GHz, 3.8 GHz, 4, 4.5 GHz, and 5.9 GHz). The CST MWS simulator is used in the design and analysis of the suggested antenna.

Locating facilities such as factories or warehouses is an important and strategic decision for any organization. Transportation costs, which often form a significant part of the price of goods offered, are a function of the location of the plans. To determine the optimal location of these designs, various methods have been proposed so far, which are generally definite (non-random). The main aim of the study, while introducing these specific algorithms, is to suggest a stochastic model of the location problem based on the existing models, in which random programming, as well as programming with random constraints are utilized. To do so, utilizing programming with random constraints, the stochastic model is transformed into a specific model that can be solved by using the latest algorithms or standard programming methods. Based on the results acquired, this proposed model permits us to attain more realistic solutions considering the random nature of demand. Furthermore, it helps attain this aim by considering other characteristics of the environment and the feedback between them.

The relative phase of the applied lights has been used to explore the position dependence of the transmitted and reflected light from a defective dielectric medium. The duplicated two-level atomic system that makes up the dielectric medium interacts with a position-dependent standing wave (SW) coupling light and a weak probe laser field. We found that identical behaviors can be produced for the transmitted and reflected light in various directions due to the relative phase of the applied light. Furthermore, we understood that the transmitted and reflected spectra of the incident light become asymmetric for the asymmetric profile of the coupling light, and that these circumstances will cause the probing field to be amplified. In this instance, we found that altering the relative phase of the applied lights can modify the position of the subluminal and superluminal light.

Robotic surgery has become one of the necessary techniques in many surgeries, including gynecological surgeries, urology, prostate, cardiac operations, catheters, arteries, and brain surgeries. The research problem is small wounds that, in the past, required a high level of expertise and an absolute focus to perform them. The robot helps the surgeon in surgeries that require working through tiny incisions; the robot can fix the telescope without movement or fatigue. The doctor was able to control its movements very accurately. Robots today assist the surgeon in many surgical interventions; minimally, the robot supports the surgeon with excellent vision, image, and precision to perform accurate surgeries with minimal surgical intervention. In this research, a general systematic literature review was performed on surgery robots.

The SO2 oxidation by using of the Cu-carbon nanotube and Cu-borne nitride nanotube is investigated by LH and ER mechanisms. The Eformation values of CNT (7, 0), BNNT (7, 0), Cu-CNT (7, 0) and Cu-BNNT (7, 0) are negative and so the CNT (7, 0), BNNT (7, 0), Cu-CNT (7, 0) and Cu-BNNT (7, 0) are stable structures, from thermodynamic viewpoint. Based on abilities of Cu-CNT and Cu-BNNT, SO2 is joined to Cu-surface-O2* to produce intermediate. The cis-Cu-surface-O-SO2-O* in ER is more stable than corresponding complex in LH. Results indicated that the most stable complexes of O2, SO2 and SO3 species have lower EHLG values than other corresponding complexes, significantly. The ER pathway can be considered to oxidize of SO2 molecule via Cu-CNT and Cu-BNNT surfaces. The ER pathway is recommended pathway to creation of primary SO3 molecule as main step in SO2 oxidation (SO2 + Cu-surface-O2* -> SO3 + Cu-surface-O*). Finally, the Cu-CNT and Cu-BNNT can catalyze oxidation of SO2, efficiently.

Graphene is one of the most important two-dimensional carbon allotropes with a plate structure similar to honeycomb nets. Due to its high thermal conductivity (TC), it is an excellent material for the thermal management of electronic nano-components. Investigating and obtaining thermal attributes of graphene for use and replacement in electronic components to study the cooling of parts is one of the important topics discussed by researchers. This research investigates monolayer graphene (MG) and helical graphene (HG). First, the TC of MG is calculated and compared using the equilibrium method (Green-Kubo) and the non-equilibrium method. The produced graphene sheets are usually not perfect and have various defects affecting graphene’s thermal and mechanical attributes. Then, the impact of nitrogen doping defect on the TC of MG is investigated. In addition, three samples of HG in different dimensions are simulated using the non-equilibrium method. The TC for each of these samples is obtained and compared. Finally, as an innovation of this research, simulated graphene coated with hydrogen atoms and TC are calculated for this model. The results show that nitrogen doping in the graphene structure reduces the amount of TC. The TC of HG depends on the effective length of the structure and the cross-sectional area of the structure. Also, the TC was reduced by hydrogenating the HG structure.

This study focuses on distributed generation (photovoltaic power plant).We evaluated material theories and solar energy distribution difficulties.The 100-kilowatt photovoltaic power plant's technical and economic features were then determined.Growing global population, finite energy supplies, and the negative environmental effects of irresponsible fossil fuel consumption have pushed renewable energy to the forefront of global concern.These factors have influenced the global trend toward renewable energy.This article introduces photovoltaic systems as a new energy source and calculates their technical and economic characteristics.Promoting the use of these systems, especially in areas remote from the electricity distribution network, while mitigating network development and fuel supply problems could reduce fossil fuel consumption.This method works in rural areas without electrical distribution.During the summer, the deviation angle is 15 to 20 degrees less than the latitude, and vice versa during the rest of the year.It reduces greenhouse gas emissions significantly, and in the near future, it will be economically feasible to do so if production of these systems is increased and construction costs are reduced.

Environmental concerns and higher energy demand require more energy.Solar and wind are renewable energies.One of the most important and available renewable energy sources is the use of wind and solar sources.This study examines energy generation and battery storage systems for lowering peak load and smoothing a residential substation's load curve.This study aims to present a useful and effective mechanism for improving the design of a hybrid system using solar panels and wind turbines to provide the common peak load and as much actual load demand as possible at the desired location.The proposed method provides the optimal solution after obtaining light radiation, wind speed, and load demand.Training and learning-based algorithms optimize.This study focuses on reducing lifetime costs.Prices and equipment are accurate, and power plant costs include initial and ongoing costs.PSO optimizes Karachi's anemometer and radiation data.The results showed that the network's summer, fall, and winter peak outputs are 12368 kW, 14865 kW, and 77 147 kW; the systems are 68.31kW, 29.38 kW, and 2337 kW.Using the seasonal average rather than the annual average improves the system's dependability and provides a more accurate response to the desired peak load.Wind and solar hybrid systems connected to the grid can reduce the grid's peak load and total cost over time.

Due to the widespread use of antibiotics in geese, water contamination by antibiotics has become a major problem. Photocatalyst semiconductors can play an important role in removing these pollutants from the aquatic environment by using sunlight. In this work, ZnO/Co3O4 nanocomposites as a new magnetic semiconductor is introduced to remove the antibiotics azithromycin and ciprofloxacin. First, the nanocomposite is synthesized by a simple co-precipitation method. Then, the crystalline and morphological properties of the prepared nanocomposite are identified by X-ray powder diffraction (XRD) and scanning electron microscope (SEM) methods. Also, the magnetic properties of the sample are analyzed by vibratingsample magnetometer (VSM) technique. Because the photocatalytic properties of semiconductors directly depend on their optical properties and energy gap, the optical properties of the prepared nanocomposite are fully studied by the UV method. Photocatalytic results showed that the prepared nanocomposite could significantly remove antibiotics from the waste water. The prepared nanocomposite was able to degradation 84.5 % and 71.7% of ciprofloxacin and azithromycin in 80 minutes under visible light respectively.

The practice of urban landscaping has many positive effects, both on the environment and the local economy. By shading buildings, absorbing sunlight, reducing UV light, cooling the air, and decreasing wind speed, these advantages include a reduction in indoor temperature. In the present study, tree planting patterns as a green belt surrounding an office building (Pematangsiantar Road Administration building) have been explored in an effort to reduce energy consumption. For this objective, three potential tree planting layouts at a distance of 10 m from the structure were examined. The cuckoo search method was used to identify 21 ideal planting situations out of 1020 possibilities. The tree was modeled using quantitative parameters of the Yackandandah species, including crown diameter, height, and trunk diameter. To validate the results, the temperature and relative humidity diagrams from the simulated building were compared with the actual data from the heat and humidity sensors. The results demonstrated that there is a substantial difference in building energy usage across different arboricultural models and instances. Compared to directed models, simultaneous tree planting in all directions of the building led to the lowest energy use. This phenomena can reduce the surface temperature of buildings and the need for cooling energy by up to 16 percent during warm seasons. According on the findings of an annual energy audit, annual energy savings could range between $400 and $1100.