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Lighting system design is a significant component of building and is considered as an important aspect when addressing sustainability of buildings. Achieving sustainability in buildings would tackle through energy conservation and waste savings. In most of the industrialised countries, rising energy costs make indoor artificial lightings as a significant contributor. Thus, visual comfort within the indoor environment could be affected by an energy-saving strategy. This paper organises a systematic state of the art review of indoor lighting simulation related to the buildings research. Simulation allows artificial objects and dynamical role variations to optimise the maximal use of lighting systems in buildings. Thus, it allows equivalent lighting system design and the synthetic environment in a virtual world. This strategy makes it possible to design and select the subjective state of the physical and virtual well-being of the visual comfort in the buildings. The main objective of this paper is to find out the most popular simulation tool adopted for the simulation of lighting in the building prototypes by various researchers. The simulation platforms are categorised in simple tools and integrated tools. The survey comprises of seventy papers which were thoroughly reviewed. It is observed that various relevant studies were carried out by different researchers in the energy savings and lighting in buildings and their prototypes were found during the survey. This research can positively aid the researchers and energy managers in deciding the feasible simulation tool for simulating their respective prototypes.

Background: Peripheral arterial disease is defined as a clinical disorder in which there is a stenosis or occlusion of the arteries of the limbs. The most common etiology is ischemia due to occlusive disease. The objective of this study is to assess the severity of lower-limb peripheral arterial diseases based on various Doppler parameters. Methods: This descriptive cross-sectional study comprised 55 patients with clinical signs and symptoms of lower-limb peripheral arterial disease. Both inpatients and outpatients attending the authors' institute were taken up for the study. In this study, Doppler sonography was performed using 3–12 MHz linear array and 1–7 MHz curvilinear array transducers (SAMSUNG RS80A Ultrasound System). Results: Out of 55 patients, Doppler sonography demonstrated echogenic plaques in 32 patients and corkscrew collaterals in 15 patients. Monophasic waveform with peak systolic velocity ratio of >2:1 was found in 42 patients, which is consistent with significant stenoses. Conclusion: Our study shows that Duplex Doppler sonography aided by color Doppler sonography can accurately locate the site and severity of stenosis/occlusion. It is safe, cost-effective, repeatable, and noninvasive.

Jaya algorithm (JA) is a single-step metaheuristic optimization technique that is free from algorithm-specific parameters. Regardless of its simplicity, JA proved its effective performance against the variety of optimization algorithms (Du et al., 2018). However, like other swarm-based optimization techniques, the JA also suffers from the inadequacies of slow or premature convergence (Farah and Belazi, 2018). In this study, an improved variant of JA (IJaya) is proposed whose functioning depends on the randomly initiated bounds based grid-oriented weight parameters. Initially, aiming to balance the global exploration and local exploitation capabilities of JA, a dynamic weight parameter is introduced as a varying coefficient for the entire solution updating expression of JA. Then, to maintain the population diversity and to mitigate the complexity of parameter tuning, the introduced weight parameter is dealt with the randomly selected parameter bounds based grid-search mechanism. The proposed IJaya algorithm is benchmarked on well-known 15 unconstrained mathematical test functions, and its performance is analyzed against the standard JA, one modified variant of JA, some well-known state-of-the-art, and few newly introduced optimization algorithms. Furthermore, the non-parametric Friedman and Quade rank tests are also conducted which confirmed the superiority of proposed IJaya both in convergence rate and solution quality. The paper also presents the results obtained by IJaya in two classical structural design problems (a cantilever beam and a 3-bar truss) and a real-world electrical power engineering problem. Numerical results clearly prove the efficiency of the proposed algorithm.

Carica papaya Linn is the member of Caricaceae family of Kingdom Plantae. The study was executed for the development of qualitative standards of male and female leaves of the plant. The study included evaluation of macroscopial, physico-chemical and preliminary phytochemical parameters to authorize the purity and authenticity of leaf of Carica papaya Linn based on guidelines provided by WHO. Qualitative phytochemical screening of extracts revealed the existence of alkaloids, flavonoids, tannins, phenolic compounds, glycosides including cardiac glycosides, proteins and carbohydrate in different extracts of Carica papaya Linn which are majorly rich in female leaves as compared to male. Mean ash values, acid insoluble ash, water soluble ash, foaming index, swelling index and moisture contents were also evaluated which are more or less similar. FTIR profile of the samples were also generated that confirmed distinct peak values with respective functional groups exhibited by Carica papaya male and female plant. The current research reflected that female and male plant showed variations in phyto-constituents. This data will be utilized for additional Pharmacological and Instrumental evaluation of the plant which can not only be beneficial in discriminating and refining the type as well as nature of various phytochemicals present in Carica papaya male and female leaves but also establish the quality standards for future researches.

Bacterial cellulose (BC) is a promising biopolymer with wound healing and tissue regenerative properties but lack of antimicrobial property limits its biomedical applications. Therefore, current study was proposed to combine wound healing property of BC with antimicrobial activity of montmorillonite (MMT) and modified montmorillonites (Cu-MMT, Na-MMT and Ca-MMT) to design novel artificial substitute for burns. Designed nanocomposites were characterized through Fe-SEM, FTIR and XRD. The antimicrobial activities of composites were tested against Escherichia coli, Salmonella typhimurium, Citrobacter fruendii, Pseudomonas aeruginosa, Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus. Tissue regeneration and wound healing activities of the composites were assessed in burn mice model. Physico-chemical characterization confirmed the loading of MMT onto surface and BC matrix. Modified MMTs-BC nanocomposites showed clear inhibitory zone against the tested pathogens. Animals treated with modified MMTs-BC nanocomposites exhibited enhanced wound healing activity with tissue regeneration, reepithelialization, healthy granulation and vascularization. These findings demonstrated that modified MMTs-BC nanocomposites could be used as a novel artificial skin substitute for burn patients and scaffold for skin tissue engineering.

This paper presents the performance analysis of an integrated renewable energy based power generation system with DC micro grid setup. The designed system comprises of wind generator (WG) system, photovoltaic (PV) panels, battery, charge controllers and DC loads as its major components. PV panels have the major contribution of supply hence it is the primary source for the designed system. WG acts as a secondary source because of its lower contribution in the supply. Lead acid battery is used as an energy storage system (ESS) to make the system more reliable by fulfilling the supply demand gap between the source and load. The proposed system presents a low cost, simple design integrated system based on basic electronic components with key features of stable voltages at load terminals, overvoltage and low voltage protection for load, back feed power flow protection for sources and overcharge and discharge protection for the battery backup. Real time results have been presented and proved that voltages have been maintained at the load terminals with small variation of 10–12%. This makes the system efficient and does not create much adverse effects on the load performance. The proposed system is suitable for off-grid remote areas facilities which offers reliable, cost effective and efficient system that maintains the voltage stability and improves the battery life.

Due to the lack of inertia and uncertainty in the selection of optimal Proportional Integral (PI) controller gains, the voltage and frequency variations are higher in the islanded mode of the operation of a Microgrid (MG) compared to the grid-connected mode. This study, as such, develops an optimal control strategy for the voltage and frequency regulation of Photovoltaic (PV) based MG systems operating in islanding mode using Grasshopper Optimization Algorithm (GOA). The intelligence of the GOA is utilized to optimize the PI controller parameters. This ensures an enhanced dynamic response and power quality of the studied MG system during Distributed Generators (DG) insertion and load change conditions. A droop control is also employed within the control architecture, alongside the voltage and current control loops, as a power-sharing controller. In order to validate the performance of the proposed control architecture, its effectiveness in regulating MG voltage, frequency, and power quality is compared with the precedent Artificial Intelligence (AI) based control architectures for the same control objectives. The effectiveness of the proposed GOA based parameter selection method is also validated by analyzing its performance with respect to the improved transient response and power quality of the studied MG system in comparison with that of the Particle Swarm Optimization (PSO) and Whales Optimization Algorithm (WOA) based parameter selection methods. The simulation results establish that the GOA provides a faster and better solution than PSO and WOA which resulted in a minimum voltage and frequency overshoot with minimum output current and Total Harmonic Distortion (THD).

The cyclical nature and high investment costs of the wind and photovoltaic renewable energy sources are the two critical issues seeking attention for the use of such systems in backup or isolated applications. This paper aims to present the experimental and economic analysis of a wind–photovoltaic-based hybrid direct current microgrid (DCMG) system for backup power and off-grid isolated power generation system for emergency purposes. The two distributed generating units comprising photovoltaic panels and wind generator were designed and developed for the experimental study. A lead-acid battery is also added as an energy storage system to enhance the system supply. The electric load of this system comprise of 42 DC light emitting diode (LED) lamps of 12 Watt each and a 25 Watt DC fan. The charge controller provides the control and protection features for the designed system. The complete system design and fabrication of this system have been undertaken at Mehran University of Engineering & Technology (MUET, Jamshoro, Pakistan). The compatibility of the designed system has been analysed by comparing the Levelized Cost of Energy (LCOE) with a conventional gasoline generator system of the same capacity. The capital, running and lifetime costs of DCMG are found to be 1.29, 0.15 and 0.29 times those of the gasoline generator, respectively. Moreover, it is found that per unit cost of gasoline generator is $0.3 (i.e., PKR 31.4) which is almost 3.4 times higher than that of the hybrid DCMG system. The performance and cost evaluation of the designed system indicate its broad potential to be adopted for commercialisation to meet backup power and off-grid power requirements. This study concludes that proposed DCMG system is a not only low cost, but also a pollution-free alternative option compared to the existing traditional small gasoline generator system.