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The industrial sector of Pakistan is currently facing severe load-shedding, which ultimately affects its unit production. The greater dependency on conventional energy resources (Thermal, Nuclear, etc.) results in higher production costs and environmental pollution. A sustainable, cost-effective, and environment-friendly solution can help the industrial growth of Pakistan. This article proposes an optimal hybrid energy system (HES) for the industrial sector of Pakistan to overcome the mentioned challenges. The proposed HES is developed in HOMER Pro. Three different energy cases (Case I: Existing energy system including a utility grid and diesel generator, Case II: On-grid Biogas system, and Case III: On-grid PV system with batteries) are considered for the Gourmet food Industry in the Sundar Industrial estate, Pakistan. The Load profile of the selected site was calculated through on-site visits and data provided by the designated utility grid feeder. The analysis shows that Case III is more effective than other cases, indicating reduced Net Present Cost (NPC), Cost of Energy (COE), and Operating Cost (OC) to $ 19.2 million, $0.034/kWh, and $ 573,371/year respectively. Moreover, the On-grid PV system with batteries (Case III) provides an environmentally friendly solution by reducing 63.82% by and 62.22% . Comparing the sensitivity analysis for various grid sell-back prices ($0/kWh, $0.043/kWh, $0.061/kWh, and $0.09/kWh), Case III is more cost-effective than Case II. The revenue generation in Case III is $128,499.41/yr, considering the supply of excess electricity into nearby small industrial loads at $0.065/kWh, this indicates that installing optimal HES in industries will not only help in overall cost reduction but also support in mitigating environmental pollution and load shedding. [ABSTRACT FROM AUTHOR]

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This study suggests a new measure for a firm's operating cost flexibility. Flexible firms are less risky and, therefore, require lower stock returns. This analysis of 126,202 firm-year observations from the U.S. cross-section of stock returns finds that the new measure explains a negative significant rate of return. The new measure's impact extends beyond that of operating leverage. In addition, the new measure's impact is both statistically and economically significant, and it is sustainable for a variety of in-sample and out-of-sample robustness tests. The new findings are beneficial to researchers and practitioners alike. [ABSTRACT FROM AUTHOR]

The performance of electrocoagulation (EC) was studied by conducting experiments for the removal of Reactive Orange 4 dye from its synthetic aqueous solution. The effect of operational parameters (initial solution pH, current density, inter-electrode distance, electrolysis time and retention time, solution temperature, conductivity and different electrode combinations) on the efficiency of EC was studied and the results were analysed in terms of colour removal efficiency (CRE), electrical energy consumption (EEC) and operating cost (OC). The effect of different anions on the efficiency of EC was studied by conducting experiments with electrolytes containing chloride, sulphate, carbonate and nitrate ions. The characterisation of EC generated sludge was performed using XRD. A maximum CRE of 95% was obtained for EEC of 1.7 kWh/m3 and OC of 0.45 US $/m3. It was found that the addition of electrolyte containing chloride ions resulted in higher CRE (93–95%) compared to electrolytes containing sulphate and carbonate ions as their presence can lead to passivation of the electrode surface & thereby resulting in a reduction in CRE (60% and 41%, respectively). The addition of sodium chloride as an electrolyte resulted in minimum EEC and OC. The Al/Al electrode combination provided the maximum CRE and least EEC & OC. The increase in solution temperature leads to reduction in CRE and CE due to formation of passive layer on the surface of electrodes. However, a reduction in cell potential and EEC was noticed with an increase in solution temperature. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) play a crucial role in modern urban water environmental protection. However, they face challenges related to high operational costs and carbon emissions. This study focused on addressing these issues through an analysis of four urban WWTPs in Jiujiang city, China. The study involved comparing the size and processes of the plants, evaluating influent and effluent water quality, assessing energy consumption and chemical usage, and calculating both direct and indirect carbon emissions. The results demonstrated that the high operational costs and increased carbon emissions in these WWTPs were primarily attributed to low hydraulic loadings, low influent concentration, and high energy and chemical consumption. In response, three targeted scenarios were proposed to enhance the efficiency of the WWTPs and reduce carbon emissions. These scenarios involved adjusting the amount of wastewater imported into the WWTPs to meet the designed capacity, optimizing operating costs, or combining both approaches. Among the scenarios, Scenario 3 emerged as the most effective in terms of improving efficiency and reducing carbon emissions. The operational costs for WWTPs could be reduced in the range of 0.42-1.04 RMB/m3, representing a reduction rate of 35%-57%. Additionally, carbon emissions could be lowered from 15.02 to 598.85 gCO2e/m3, corresponding to a reduction of 2.91%-41.38%. Although Scenario 2 exhibited a lower carbon emission reduction of 14.8-316.33 gCO2e/m3, it was identified as the most feasible and easily implementable high-efficiency solution at present, with a reduction in operational costs ranging from 0.43 to 1.31 RMB/m3. To achieve zero energy consumption and zero carbon emissions in wastewater treatment in the future, it is recommended to undertake additional measures, such as enhancing dosing system accuracy, implementing tail gas collection, adopting photovoltaic power generation, implementing carbon sequestration techniques, and exploring wastewater heat source recycling. These findings provide valuable insights for optimizing the operational efficiency of urban WWTPs, reducing carbon emissions, and promoting sustainable wastewater treatment practices in Jiujiang city, China. [ABSTRACT FROM AUTHOR]

Due to the high cost and complex challenges faced by offshore wind power transmission, economic research into offshore wind power transmission can provide a scientific basis for optimal decision-making on offshore wind power projects. Based on the analysis of the topology structure and characteristics of typical wind power transmission schemes, this paper compares the economic benefits of five different transmission schemes with a 3.6 GW sizeable onshore wind farm as the primary case. Research includes traditional high voltage alternating current (HVAC), voltage source converter high voltage direct current transmission (VSC-HVDC), a fractional frequency transmission system (FFTS), and two hybrid DC (MMC-LCC and DR-MMC) transmission scenarios. The entire life cycle cost analysis model (LCCA) is employed to thoroughly assess the cumulative impact of initial investment costs, operational expenses, and eventual scrap costs on top of the overall transmission scheme's total cost. This comprehensive evaluation ensures a nuanced understanding of the financial implications across the project's entire lifespan. In this example, HVAC has an economic advantage over VSC-HVDC in the transmission distance range of 78 km, and the financial range of a FFTS is 78–117 km. DR-MMC is better than the flexible DC delivery scheme in terms of transmission capacity, scalability, and offshore working platform construction costs in the DC delivery scheme. Therefore, the hybrid DC delivery scheme of offshore wind power composed of multi-type converters has excellent application prospects. [ABSTRACT FROM AUTHOR]

This study investigates the combined effects of UV/TiO2 and UV/H2O2 processes on the degradation of 1,2-dichlorobenzene in aqueous media, employing a recycled current photo-reactor equipped with a water jacket. Evaluation of various factors—initial pH, TiO2 dosage, initial H2O2 concentration, pollutant concentration, and temperature—contributed to the optimization of degradation rates and operational costs for both processes. For the degradation of 50 mg/L of DCB, the optimal operating conditions were found to be for UV/TiO2: pH = 3, [TiO2] = 30 mg/L and T = 25 °C, and for UV/H2O2: pH = 3, [H2O2]0 = 350 mg/L and T = 25 °C. After 60 min of irradiation time, the degradation efficiency, pseudo first order rate constant and operational cost value for the UV/TiO2 and UV/H2O2 processes were as 98.9%, 0.0771 min−1, 11.6 $/m3 and 96.3%, 0.0573 min−1, 11.8 $/m3 respectively. Also, thermodynamic parameters of activation energy, enthalpy change, entropy change and standard Gibbs free energy were calculated as 21.78 (kJ/mol), 19.37 (kJ/mol), − 0.20 (kJ/mol K) and 73.34 (kJ/mol at 25 °C) for UV/TiO2 process and 7.62 (kJ/mol), 5.18 (kJ/mol), − 0.25 (kJ/mol K) and 80.14 (kJ/mol at 25 °C) for UV/H2O2 process. The investigation also encompassed the exploration of 13 hybridization scenarios, including UV/TiO2/H2O2 and UV/H2O2/TiO2, revealing notable findings. Notably, a specific hybridization scenario, namely UV/TiO2 (30 mg/L)/H2O2(250 mg/L), demonstrated a significant synergistic effect (29.5%). Evaluating pollutant mineralization unveiled compelling results, with approximately 85% mineralization achieved after 90 min for the UV/TiO2(30 mg/L)/H2O2(250 mg/L) scenario, showcasing a remarkable synergism (44%) in the mineralization process. [ABSTRACT FROM AUTHOR]

Water pollution is one of the major problems for humankind. Various pollutants could be detected in wastewater because of human activities such as industrialization, agriculture, domestic waste and etc. Removal of pollutants such as heavy metals, dyes, oils and pesticides are of great importance which affects human life negatively. Many methods have been extensively used to provide "clean water" for environment and human. Heavy metals are important industrial pollutants that need to be quickly removed from wastewater due to their high toxicity and non-biodegradable structure. In this paper, the heavy metals including copper, nickel and zinc have been examined in real wastewater from metal plating industry in Bursa, Türkiye. Concentrations of pollutants (Cu, Ni, Zn, chemical oxygen demand (COD) and SO4) in the effluent as a result of coagulation-flocculation process were determined and their compliance with sewage discharge standards was investigated. Moreover, the removal efficiencies of the pollutants were examined (Cu and Ni: 97-100%; Zn: 82-98%; COD: 32-54%; SO4: 16-23%) and the effect of the coagulant doses used on the operating cost, sludge quantity were also discussed. [ABSTRACT FROM AUTHOR]

Nordic forests, like those found in Canada, used to consist of large and relatively homogeneous mature stands. Such a spatial pattern allows for harvest operations to be highly concentrated, minimizing procurement costs. However, the growing fragmentation of these forests makes planning difficult and increases the costs of road building and machinery relocation. While operational solutions have been developed in regions with small harvest areas, their transferability to different settings is unknown. Finding the most suitable combination of equipment for a given context is challenging considering the multitude of possibilities. The objective of this study is to identify, from all possible options, a subset of harvest systems expected to perform well in fragmented boreal forests. The results from this research are two-fold. First, a comprehensive review of forest machines and harvest systems is provided. Second, a multi-criteria decision analysis (MCDA) methodology is proposed to evaluate the alternatives. In a boreal forest context, the conventional harvester-forwarder system (CTL) was ranked among the best solutions, along with mild adaptations of the usual configurations. Several whole-tree (WT) system configurations were also highly ranked. While the results are specific to the case studied, the review and selection methodology can serve in different operational contexts. [ABSTRACT FROM AUTHOR]

Purpose: Consumer goods firms often tie up inventory and accounts receivable resources, creating cost and liquidity issues. Dynamic working capital management (DWCM) can mitigate these concerns and enhance operational profitability. The study investigates DWCM's impact on operational efficiency (OE). Design/methodology/approach: The empirical estimation uses pooled ordinary least squares (OLS), random effect and system generalized method moments (GMM) regression analysis of consumer goods firms in Scandinavia from 2005 to 2022 to present the results. Findings: The findings indicate that DWCM has an inverse relationship with operating cost, while positively impacting operating profit. The final outcome demonstrates that DWCM enhances OE. Furthermore, the working capital ratio (WCR) consistently exceeds the cash conversion cycle (CCC) in all models, indicating that prudent management of cash in accounts receivable, inventory and accounts payable leads to higher cost savings and superior performance. Practical implications: The results suggest that organizations that prioritize the management of the absolute cash committed to inventory, receivables and payables as much as the CCC experience improved OE. Originality/value: This paper adds to the literature on how DWCM affects OE in the consumer goods sector. It also highlights the impact of time management and cash management in WCM on OE. Additionally, it analyzes how DWCM variables affect operating costs and profits, shedding light on their efficiency impact. [ABSTRACT FROM AUTHOR]

This study proposes an innovative hydrogen storage capacity optimization configuration method that considers multiple demand factors, addressing the issue that traditional methods for optimizing hydrogen storage capacity in hybrid microgrids cannot simultaneously balance economic efficiency and grid connection quality. This method breaks through the traditional optimization framework and adopts a double-layer optimization model, combining the peak shaving operation cost of the hybrid microgrid with the interactive power deviation and power fluctuation penalty terms of the interconnection line during the frequency regulation stage, achieving dual optimization of economy and grid connection quality. Through precise mathematical modeling and efficient optimization algorithms, we have successfully obtained the minimum operating cost corresponding to the minimum power fluctuation, the minimum interconnection line interactive power deviation penalty term, and the optimal hydrogen storage capacity configuration scheme. Identify two typical days through cluster analysis. Option 1 (considering peak shaving, frequency regulation, and hydrogen electrolysis) has the lowest net load and a total operating cost of 3.0331 million yuan, which is better than Option 2 (3.0973 million yuan) and Option 3 (5.0398 million yuan). This plan effectively reduces wind and solar power waste, shortens the operating time of thermal power units, and demonstrates the rationality and economy of optimizing hydrogen storage capacity configuration.

The purpose of this research is to identify the optimal configuration of a diesel generator with a hybrid renewable energy system that can sustainably meet the energy demands of a rural area. Some of the main challenges of using diesel generators to supply the required electric load in remote areas are the high operating cost, unmet electric load, carbon dioxide emissions, very high total net cost, and the quality of electricity. This study, which combined diesel generators with renewable resources, accurately analyzed eight different system outputs from the hybrid optimization of multiple energy resources software. The analysis considered factors such as site-specific conditions, fuel costs, and solar radiation levels. The software prefers a load following strategy over a cycle charging strategy. This load following strategy involves combining a diesel generator with renewable energy sources, specifically configured as a combination of photovoltaic cells, a diesel generator, a wind turbine, and a battery. This configuration, with a total net cost of approximately $180,065.43 and a levelized cost of energy of $0.32, is identified as the most effective configuration chosen. Operating cost, carbon dioxide emission, and total net present cost are reduced by 53.17 %, 60.46 %, and 30.02 %, respectively. It highlighted the combination of diesel generator with renewable energies and their role in promoting environmental sustainability. By providing 100 % of the load demand, it increased the quality of electricity such that the unmet electric load is reduced to zero.

Reactive power planning has attained a pivotal role for improved coordination in modern power system as minimization of transmission loss is an essential criterion for secured power system operation. This article proposes a meta-heuristic nature inspired Harris Hawk Optimizer (HHO) and Oppositional based Harris Hawk Optimizer (OHHO) algorithms which are implemented on standard Ward hale 6 bus system and IEEE 30 bus system. The HHO is a derivative free algorithm and does not exhibit any internal dependent parameters. Further, the search space is modified by hybridizing HHO with oppositional based learning technique in order to achieve enhanced approximation for the prevailing solution and the OHHO is proposed in the current work for minimization of transmission losses, operating cost and enhancement of voltage profile at the buses. The influence of updating mechanism of the optimizers is investigated with respect to the objective functions. The work majorly focuses on the constraints like reactive power generated by generator buses, shunt capacitors and transformer tap changing position. The simulation results obtained on standard test systems manifest the improved performance of proposed HHO and OHHO in comparison with the other optimization techniques that have emerged in the recent state-of-the-art literature. [ABSTRACT FROM AUTHOR]

Textile industries are water intensive and the effluent generated contains salts, dyes, and heavy metals as well as having a high biological oxygen demand (BOD) and chemical oxygen demand (COD), therefore it must be treated before being discharged into the aquatic environment to prevent its contamination. Electrocoagulation (EC) is a promising technique to treat domestic and industrial effluent, where in situ coagulants are produced by sacrificial dissolution of the anode by application of an electric current across the electrodes. The effect of punched-hole electrodes on the performance of EC—color removal efficiency (CRE), electrical energy consumption (EEC), and operating cost (OC)—was studied by varying the number and diameter of holes in the electrode. It was observed that the use of punched electrodes resulted in higher CRE, lower EEC, and lower OC as compared with plane electrodes. The difference in CRE obtained using plane and punched electrodes was found to increase with an increase in current. The effect of punched-hole electrodes on the treatment of real dye effluent was studied and COD removal of 78.79% was obtained using punched-hole electrodes as compared with 69.30% using plane electrodes. The EEC and the OC were found to be 0.5 kW·h/m3 and US$0.424/m3, respectively, for punched-hole electrodes. [ABSTRACT FROM AUTHOR]

The analysis of energy consumption in reverse osmosis desalination plants is the most important and relevant factor to study, because this parameter indicates the level of efficiency and competitiveness of the plant. The direct consequence of the high specific energy consumption (SEC) of a desalination plant in the production of water is one of the main obstacles to the exponential expansion of this technology worldwide. The methodological procedure used to carry out the work is based on the analysis of energy consumption, maintenance costs, staff, membranes, and reagents of three desalination plants with a production of more than 23,000 m3/day located in the Canary Islands (Spain); all data are obtained from real analyses collected "in situ" from 2015 to 2018. One of the main objectives of the current research on desalination plants is to reduce the SEC of seawater desalination plants (SWRO), incorporating energy recovery systems (ERS) and high efficiency pumps (HEP), and to implement different operational configurations with the aim of minimizing the energy requirements necessary to obtain a good product quality at minimum production cost. [ABSTRACT FROM AUTHOR]

The confectionery wastewater contains high amount of biodegradable organic matter with an acidic characterization that should be treated before the discharge to receiving water bodies. The post-treatment method should be combined with biological treatment in order to enhance the treatment performance. In this study, chemical coagulation (CC) and electrocoagulation (EC) processes were studied as post-treatment methods for anaerobically treated confectionery wastewater. The influences of operational conditions such as pH, coagulant dosage for CC process and pH, current density, treatment time, electrode connection type for EC process were investigated. The conditions were optimized based on treatment performance and operating cost. Scanning electron microscopy–energy-dispersive index (ESEM–EDX) analysis was performed for the sludge samples. The removals of 65% COD, 84% SS and 93% DFZ436 were obtained using ferric chloride in CC process. EC process with Fe electrode achieved better removals compared with CC providing 77% COD, 93% SS, 93% DFZ436, 84% sulphate and 60% chloride removals under the optimized conditions (pH 8, 90 A/m2, 75 min, MP–P). Although EC process provided a higher operating cost (5.9 $/m3) compared with CC process (5.4 $/m3), it was able to meet the discharge standards for confectionery industry effluent. [ABSTRACT FROM AUTHOR]

AbstractHospitals play a crucial role in providing medical care to patients, but they also have a significant environmental impact due to their high energy consumption and resource use. In recent years, there has been growing interest in the concept of green hospital design, which aims to reduce the environmental footprint of hospitals while simultaneously improving patient outcomes.10 articles were finalized for review and were coded in QDA Miner qualitative analysis software for descriptive and link analysis. Results indicated a strong correlation between green design aspects of hospital and patient well-being, it failed to provide any evidence of concrete relation between relation between green hospital design and lower operation cost.” [ABSTRACT FROM AUTHOR]

This paper introduces an optimal bi-objective optimization methodology customized for microgrid systems, encompassing economic, technological, and environmental considerations. The framework portrays the objectives of an intelligent microgrid, aiming to minimize operational costs, CO2 emissions, peak-to-average ratio (PAR), and energy consumption while concurrently enhancing user comfort (UC). A scheduled power allocation strategy is formulated to efficiently cater to the energy needs of residential loads. The stochastic nature of wind and solar resources is characterized by modeling wind speed and solar radiation intensity using a beta probability density function (PDF). The non-dominated sorting genetic algorithm II (NSGA-II) is employed to address optimization challenges. A decision-making process is implemented to select the optimal solution from the non-dominated alternatives. The study presents three scenarios illustrating the optimal operational values for various parameters and energy consumption, providing a comprehensive analysis of the proposed algorithm’s efficacy. Leveraging the NSGA-II algorithm, coupled with renewable energy resources and optimal energy storage system scheduling, yielded significant reductions in overall expenses, PAR, CO2 emissions, user discomfort, and energy consumption. MATLAB simulations were conducted to substantiate the efficacy of our proposed approach. The obtained results underscore the effectiveness and productivity of our devised NSGA-II-based approach. Notably, the proposed algorithm demonstrated a substantial reduction in electricity costs by 19.0%, peak-to-average ratio (PAR) by 30.7%, and carbon emissions by 21.7% in scenario-3, as evidenced by a comparative analysis with the unscheduled case.

This study suggests a new measure for a firm’s operating cost flexibility. Flexible firms are less risky and, therefore, require lower stock returns. This analysis of 126,202 firm-year observations from the U.S. cross-section of stock returns finds that the new measure explains a negative significant rate of return. The new measure’s impact extends beyond that of operating leverage. In addition, the new measure’s impact is both statistically and economically significant, and it is sustainable for a variety of in-sample and out-of-sample robustness tests. The new findings are beneficial to researchers and practitioners alike.

The entire ecology is contaminated by the synthetic dyes that are widely utilised in the textile industries. They can be handled using a variety of technologies, but an eco-friendly method called electrocoagulation has been used to prevent additional contamination. Textile wastewater containing disperse dyes are successfully treated in Electrocoagulation (EC) utilizing Al, Fe, and Stainless Steel (SS), but it is not cost effective, also the treated water contains certain mg/L of the metals used, along with dye components, which obstructs the reuse of the same. The effects of initial pH, applied voltage, dye concentration, supporting electrolyte, and treatment time on the colour removal efficiency (CRE) and consumption of energy were examined in EC process followed by activated charcoal filtration (hybrid process) with a monopolar Ti/Ti electrode on the remediation of aqueous solution of Dispersive Blue-79 (dye 3G). The maximum CREobtained was 99.4%, chemical oxygen demand (COD) 93%, and biological oxygen demand (BOD) 85%, under the following optimized operating conditions, applied voltage 15 V, pH = 7, concentration of dye, electrolyte 110 mg/L, 0.2 g/L and time = 15 min. The overall operating cost for the treatment of aqueous dye 3G was 0.455US/m3. The mechanism of EC was studied using XPS analysis in the sludge obtained. For the purpose of the reuse, FTIR, AAS, and ICP-OES analysis were done and compared with the aqueous dye 3G, after EC and hybrid process to ensure the maximum removal of the degraded dye components and metal. ICP-OES results showed that there were no traces of metal in the treated aqueous dye 3G using this method. Throughout the study, the experimental outcomes indicated that the hybrid process upgraded the quality of the treated aqueous dye 3G. [ABSTRACT FROM AUTHOR]

This paper provides a cost-effective energy management method for the microgrid's standalone and on-grid operational modes. The considered microgrid based on Green-to-Green systems such as a photovoltaic array (PV), wind turbine (WT) as renewable generators, hydrogen fuel cell (FC) system, microturbine (MT), and battery storage system. The suggested technique is based on the marine predator algorithm (MPA) that and created for a scheduling horizon of one day. The main objective of this paper is to reduce operating costs while satisfying the demand power. To approve the performance of the suggested management strategy, the simulation results are compared with other recent optimization algorithms. These algorithms include particle swarm optimization (PSO), salp swarm algorithm (SSA), and coot optimization algorithm (COOT). To approve the performance of the proposed EMS, the system will be evaluated for three cases: free renewable generation, restricted generation mode, and unlimited main grid power mode. For the first case, the proposed EMS reduces the operating costs by 0.8732%. For case 2, the economic benefits have been raised by 1.0815% and by 0% for the last case because of the reduced problem complexity. • A cost-effective energy management strategy for the microgrid based PEM fuel cells is proposed. • Implementation of marine predator algorithm to minimize the operating costs. • The performance has been investigated under various operating conditions. [ABSTRACT FROM AUTHOR]

Natural water contaminated with nitrates can pose serious problems for human health and aquatic ecosystems. Thus, effective, and low-cost treatment systems that can be implemented on both large and small scales are needed. The main goals of this work were to quantify nitrate pollution of groundwater (i.e., underground well water used for drinking purposes), to identify its causes, to evaluate the performance of the electrocoagulation (EC) process in nitrate removal, optimizing the treatment procedure using synthetic water, and to estimate the process cost. A total of thirty domestic wells, located in Sidi Bel Abbes city in North-West Algeria, used for drinking water were subject to sampling. Results indicated that most of the wells had nitrate contents that exceeded the World Health Organization (WHO) guideline value as well as the Algerian permissible limit of 50 mg.L-1, with a maximum NO3- concentration of 162 mg.L-1. The pollution was presumed to be due to agricultural activity, human and animal waste, and the nature of the soil. The EC treatment tests with aluminum electrodes exhibited a high nitrate removal efficiency of 90% at a current density of 5.12 mA.cm-2, electrolysis time 15 min, pH 8.8, agitation speed 400 rpm and at an initial nitrate concentration of 50 mg.L-1. Under optimum operating conditions, nitrate removal was 88% for an initial [NO3-] of 87 mg.L-1 in groundwater. The operating cost was estimated at 0.27 US $/m³ or 0.12 US $/Kg nitrate removed. The findings from this study showed that EC is an economically viable technique for dealing with nitrate contamination for small-scale water treatment applications. [ABSTRACT FROM AUTHOR]

In order to further tap the potential of multi-energy complementarity of energy Internet, improve the operating income of energy system and reduce the operating cost, an optimization method of load-source coordination of multi-energy hub considering consumption benefit was proposed. Considering the constraints of multi-energy system, the residential energy hub model was constructed according to minimizing the total operating cost of residential energy hub, and the industrial energy hub model was constructed with the goal of maximizing the total operating income of industrial energy hub. According to the constraints of the above two-layer model, the problems existing in the coordinated optimization of load and source are obtained, and the multi-objective mixed integer linear programming model was designed by using the multi-objective weighted optimization algorithm to realize the coordinated optimization of load and source. The simulation results show that the designed optimization method of load-source coordination of multi-energy hub considering consumption benefit can promote the consumption of renewable energy, reduce the operating cost of multi-energy hub, effectively reduce the overhead and improve the operating income of energy system, which provides a new technical way for the economic operation and load-source coordination optimization of multi-energy hub. [ABSTRACT FROM AUTHOR]

The energy management issue of microgrids typically adopts demand response programs and reconfiguration of distribution networks to improve the technical and financial characteristics of microgrids. This manuscript proposes an energy management optimization in micro grids using IoT by applying the GBDT-JS technique to account for the uncertainty introduced by renewable energy sources and electric demands. The proposed technique is a combination of gradient boosting decision tree algorithm (GBDT) and jellyfish search (JS); hence, it is called GBDT-JS technique. The proposed method is to include maximizing the benefits of microgrids and reducing power fluctuations to the main grid. This proposal presents a GBDT-JS to develop the suitable adaptive day-ahead real-time energy dispatch under the occurrence of operating uncertainty based on the energy management system (EMS). Energy dispatch is achieved to satisfy the many operating criteria based on optimum solutions which are further implemented, for example minimum power fluctuation and operating cost. The main aim of the works contributions is shortened as below: (1) The optimum GBDT system is decided day-ahead depending on the predictive microgrid system levels consider a many operating objects. (2) JS technique is improved a day-to-day basis, adopted to execute the energy dispatch, and directly present in the uncertainty system. The GBDT-JS technique is done on MATLAB, and their performance is compared to different existing techniques, such as slime mould optimization algorithm, side-blotched lizard algorithm, and jellyfish search (JS). [ABSTRACT FROM AUTHOR]

The aim of this paper is the optimal scheduling of an active distribution network at the feeder scale to achieve minimum operating costs. To achieve this goal, a two-stage stochastic programming approach is presented that consists of here-and-now and wait-and-see decisions. In order to handle the uncertain parameters in the model, with the Monte Carlo simulation approach, different scenarios were produced, and then the scenarios were reduced. As a result, the mathematical problem is formulated as a linear model programmed in GAMS and then resolved with CPLEX solver. The effectiveness of the proposed model is assured through simulation studies on the standard IEEE 33-bus test system. The operating costs were calculated under different network conditions and were compared among themselves and according to the availability of storage. Obtained operating cost results have indicated that there is 6.4% cost reduction in the case where storage is used under the same conditions, compared to the case where no storage is used. [ABSTRACT FROM AUTHOR]

Textile production is one of the largest sectors in the manufacturing industry; however, the textile dyeing process produces a voluminous amount of highly colored wastewater. The dyes used are organic compounds of different dye classes that are stable in an aquatic environment with low decomposition rates. This study investigated the removal efficiency of five textile dyes of different dye classes (Disperse Orange 30, Acid Blue 324, Basic Yellow 28, Reactive Black 5, Vat Brown 1) from wastewater by electrocoagulation (EC) process that was equipped with aluminum electrodes. EC process achieved 91.98, 98.13, 47.46, 92.55, and 82.60% removal efficiencies for AB324, BY28, VBI, and RB5, respectively, at a current density of 0.83 mA/cm2. The energy consumption for dyestuff removal was in the following order: DO30 < VB1 < RB5 < AB324 < BY28. The total operating cost per kilogram of dyestuff removed in 15 min at 0.0502 mA/cm2 was determined as 0.250, 0.274, 0.550, 0.647, and 0.764 $/kg for DO30, VB1, RB5, AB324, and BY28, respectively. The removal mechanism was well fitted to the pseudo-first-order kinetic model with R2 above 0.94 for AB324, BY28, and RB5 dyes. However, the removals for DO30 and VBI dyes were exponential and neither fitted the first-order kinetic nor second-order kinetic model. The overall removal trend was as follows: DO30 > VB1 > AB324 > RB5 > BY28. Therefore, the use of dyes that can easily be removed from wastewater should be encouraged to preserve the quality of water in the receiving environments and to reduce the cost of wastewater treatment. [ABSTRACT FROM AUTHOR]

Hua Wang,1 Xiao-Li Hu,2 Qiu-Fang Li,3 Jie Zhou,1 Ming-Yuan Wu1 1Department of NICU, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, People’s Republic of China; 2Department of Obstetrics, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, People’s Republic of China; 3Department of Nursing, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, People’s Republic of ChinaCorrespondence: Ming-Yuan Wu, Department of NICU, Women’s Hospital, Zhejiang University School of Medicine, No. 1 of Xueshi Road, Shangcheng District, Hangzhou, 310006, People’s Republic of China, Tel + 86 13958115502, Email wumy@zju.edu.cnObjectives: This study aimed to investigate the matching degree between the donated supply and demand, clinical characteristics of both donors and recipients, along with the operation cost.Methods: From January 1, 2018 to December 31, 2021, the data on human milk donation and usage, the clinical characteristics of donors and recipients, and the cost of each operating center were collected from the Manual Donation Registration Form and Information Management System of the selected human milk bank.Results: During the four years that the human milk bank was in operation, the volume of donated milk was slightly greater than the volume of consumed milk. A total of 1364 donors donated 2434.63 liters of qualified human milk, for RMB 1,791,000 (USD 257, 202), ie, RMB 385.3 (USD 55.3)/L; 97.8% of the donors were preterm puerperae, and 59% of the donors donated between 1 week and 1 month after delivery. All recipients were preterm infants and received donated human milk for a duration of 9.4 days on average. During the four years of operation, the proportion of donors who had previously received donated milk among all donors showed an overall increasing trend, while the incidence of NEC in preterm infants gradually decreased.Conclusions: The increasingly optimized structure of donors, the more economical operation, and the fact that the use of donated milk may not affect breastfeeding of the recipients have made it a human milk bank operation mode worthy of promotion.Keywords: donated human milk, human milk bank, NEC, operating cost, preterm infants

Abstract Reactive power management has grown more crucial for increased synchronization in modern power systems, since transmission loss minimization is a basic condition for secure power system operation. This paper proposes the Oppositional-based Harris Hawk Optimizer technique as an advanced meta-heuristic nature inspired methodology, which is applied on the conventional Ward Hale 6 bus system and the IEEE 30 bus system. The solution space is further altered by combining HHO with the Oppositional Based Learning technique in order to enhance approximation for the current solution. The suggested OHHO outperforms HHO as well as other optimization methodologies recently published articles, according to simulation results obtained on typical test systems.

Nordic forests, like those found in Canada, used to consist of large and relatively homogeneous mature stands. Such a spatial pattern allows for harvest operations to be highly concentrated, minimizing procurement costs. However, the growing fragmentation of these forests makes planning difficult and increases the costs of road building and machinery relocation. While operational solutions have been developed in regions with small harvest areas, their transferability to different settings is unknown. Finding the most suitable combination of equipment for a given context is challenging considering the multitude of possibilities. The objective of this study is to identify, from all possible options, a subset of harvest systems expected to perform well in fragmented boreal forests. The results from this research are two-fold. First, a comprehensive review of forest machines and harvest systems is provided. Second, a multi-criteria decision analysis (MCDA) methodology is proposed to evaluate the alternatives. In a boreal forest context, the conventional harvester-forwarder system (CTL) was ranked among the best solutions, along with mild adaptations of the usual configurations. Several whole-tree (WT) system configurations were also highly ranked. While the results are specific to the case studied, the review and selection methodology can serve in different operational contexts.

The study aims to analyze the effect of operating costs, production costs and sales on net profit. Net profit is the profit obtained from the amount of income deduction with tax withholding expenses. The research population is manufacturing entities in the basic industrial and chemical sectors listed on the Indonesia Stock Exchange in 2019-2021. Non probability sampling technique with purposive sampling method with total data 57. Multiple regression analysis is a research data analysis technique. The results showed that operating costs negatively affect net income, meaning that high operating costs have an effect on reducing the value of net profit. Production costs do not affect net profit and sales have a positive effect on net income. Future research is expected to enlarge the scope of observations so that the results obtained are more general and applicable to many business sectors.

In this paper, we propose a distributed secondary FM control method for microgrids to address the problem that the operating cost of microgrids increases significantly under load dropout and use the consistency algorithm to make the system reasonably distribute the load power to re-achieve the stable state. In the actual microgrid, the communication delay discusses the influence of information transmission and system stability. Simulation experiments are used to verify and set different convergence coefficients to obtain a suitable range of convergence coefficients. Then, the microgrid economic power allocation algorithm was used to describe the operating cost of microsources and limit the generator output power of the microgrid system to obtain the microgrid economic power allocation values. The cost amount of MG1 is $1327.3 in the equal micro-increase rate consistency calculation. The control condition test reduced 73.14 kWh in the overall load outage of intelligent microgrid control. The power system’s efficiency can be improved through a control method using intelligent information processing.

In this paper, an economically feasible and reliable operation of the IEEE 57 bus system for Optimal Power Flow (OPF) is proposed. The Improved Symbiotic Organisms Search (ISOS) algorithm is proposed for effective reactive power planning as an OPF issue. Further, the optimal position of Flexible AC Transmission Systems (FACTS) is taken into consideration, by including the existing system controlling variables like reactive power generators output, transformer tapping and capacitors connected at shunt. The objective of the work is two-fold; i.e., to reduce the energy loss and to enhance the voltage profile within the prescribed limit by ensuring the economic operation and investment cost of FACTS in the system. In this work, two FACTS devices like Static Var Compensator (SVC) and Thyristor-Controlled Series Controller (TCSC) have been taken into consideration. Voltage sensitivity indicator and reactive power flow are two tools that are utilised in order to locate weak nodes for the implementation of FACTS. Finally, the performance of the ISOS algorithm is compared with that of three other state- of-the -art optimization techniques, such as, Symbiotic Organisms Search (SOS), Differential Evolution (DE) and Teaching Learning Based Optimization (TLBO). A Non-parametric statistical analysis is also performed to investigate the dominance of the ISOS algorithm over others.

The widespread use of drones in various fields has initiated a discussion on their cost-effectiveness and economic impact. This article analyzes in detail a methodological evaluation framework for the levelized cost of drone services for law enforcement purposes. Based on the data availability, we compared two vehicles: Phantom 4 Pro and Thunder-B. Moreover, we calculated their levelized costs per surveillance time and trip distance. Our approach helps users calculate the real costs of their vehicles' services and produce equations for rapid estimations. We observed economies of scale for time and distance and showed differentiations per aircraft capacity. Furthermore, using the produced equations, we formulated a case study and compared the costs in a 4 km area constantly monitored by the two types of drones to support the best vehicle selection. We found that the Phantom 4 Pro costs less than the Thunder-B drone, for example. Thus, we demonstrate how, by applying this methodology beforehand, decision makers can select the most appropriate vehicle for their needs based on cost. Cost research estimations will improve UAV use and will help policymakers include UAV technology in crime prevention programs, especially when more data are available. [ABSTRACT FROM AUTHOR]

Yeast production wastewater is an industrial wastewater with a high organic pollutant content, and it has different adverse effects on the environment as untreated discharge. To treat this kind of wastewater with a high chemical oxygen demand (COD), advanced wastewater treatment technologies have to be used and evaluated with economic parameters for their applicability. The objective of the study was the technoeconomic optimization of ultraviolet Fenton oxidation (UV/FO) and ultraviolet electrochemical Fenton oxidation (UV/EFO) processes as a subsection of hybrid advanced-oxidation processes (AOPs) for the effective degradation of COD from ultrafiltration filtrate wastewaters, a byprocess of yeast production. In optimization studies, the influence of operating parameters such as pH, current density (CD)/Fe2+ concentration, H2O2 concentration, and economic parameters such as sludge disposal, chemical cost, electrode cost, energy cost, and total operating cost was investigated. A double-criteria optimization option has been used to maximize the COD removal efficiency and minimize the total operating cost of the processes by the response surface methodology (RSM), and parametric effects of main factors on the processes were evaluated in a detail. The optimal conditions using the UV/FO process were determined to be an initial pH of 3, Fe2+ concentration of 3.52 g/L , and H2O2 concentration of 79.76 g/L , in which the COD removal was 99.96% and the total organic carbon (TOC) removal was 76%, with a total operating cost of 16.96 $/m3 (1.73 $/kg CODrem). In the UV/EFO process, the optimum conditions were observed to be an initial pH of 3.07, current density of 5.68 mA/cm2 , and H2O2 concentration of 180.63 g/L , in which COD removal was 99% and TOC removal was 81%, with a total operating cost of 13.00 $/m3 (1.34 $/kg CODrem). Based on the obtained results, it was found that UV/FO and UV/EFO processes resulted in a considerable amount of COD removal. Almost for the same COD removal efficiency, the UV/EFO process was observed to have a lower cost in terms of sludge disposal and the chemicals used. The UV/EFO process is an effective technology improving the wastewater quality for potential reuse and a cost-effective approach. [ABSTRACT FROM AUTHOR]

This research article presents a technoeconomic analysis of an RET-based model for powering a hilly remote area telecom tower in Chamba district of Himachal Pradesh, India. Using the HOMER software tool with various evolutionary algorithms, the study found that the most feasible configuration was 30 kW of SP panels, 10 kW of DG units, 20 batteries, and 10 units of converter with a minimum energy cost value of 0.256 $/kWh. The energy cost values from various evolutionary techniques such as HHO, WOA, PSO, and GA were also observed to be competitive. After policy intervention and government subsidies, the cost of energy reduced to 0.167 $/kWh, which is significantly less compared to the diesel-powered system. Furthermore, sensitivity analysis was carried out for changes in solar radiations, ambient temperature, and diesel fuel prices to determine the best optimal configuration for the study. [ABSTRACT FROM AUTHOR]

Reactive power management has grown more crucial for increased synchronization in modern power systems, since transmission loss minimization is a basic condition for secure power system operation. This paper proposes the Oppositional-based Harris Hawk Optimizer technique as an advanced meta-heuristic nature inspired methodology, which is applied on the conventional Ward Hale 6 bus system and the IEEE 30 bus system. The solution space is further altered by combining HHO with the Oppositional Based Learning technique in order to enhance approximation for the current solution. The suggested OHHO outperforms HHO as well as other optimization methodologies recently published articles, according to simulation results obtained on typical test systems. [ABSTRACT FROM AUTHOR]

The analysis and optimization of the operational and maintenance costs of water management systems is one of the key issues of their exploitation. This article presents a general model, supported by specially designed software, able to process the analysis of exploitation costs of multistate renewable systems. The proposed model allows for the consideration of costs related to preventive inspections and repairs and additional reliability associated costs, such as costs of the system in a state of deteriorated reliability and financial losses related to reduced serviceability of the system or a lack of rendering of services. By means of a multistate approach to the reliability analysis, the model allows for the determination of the level corresponding to the appropriate reliability state that, if exceeded, should result in undertaking the repair of the system. In this study, the MATLAB 9.13 (R2022b) environment was used for simulation and estimation of the costs of system maintenance and repairs according to the proposed model. The article presents the results of the optimization of exploitation and repair costs of water management systems, allowing the estimation of the optimal period between regular inspections while maintaining the safe operation of the system. The model and software proposed can be of assistance in supporting the decision process of maintenance planning for water management systems. [ABSTRACT FROM AUTHOR]

In most of the research works, similar metal electrodes were used, resulting in high operating costs, and the reuse of the treated water was not explored. The major goal of this research is to lower the cost of the electrocoagulation (EC) process by employing electrodes made of different metals and to investigate whether it is possible to reuse the water that has been treated by doing so. It was done to optimize the operational parameters such as pH, voltage, time, electrolyte, and dye concentrations. The energy and electrode consumption was calculated as 0.29 kWh.m-3 and 3.5x10-2 kg.m-3, respectively. The HPLC and LC-MS studies shows the degradation of dye and the formation of intermediary compounds, which were less toxic. The sludge obtained from the EC process was subjected to EDX and XPS analysis to know the composition of metals and the formation of metal hydroxide coagulants. The phytotoxicity of the treated water after EC was examined using Trigonella foenumgraecum seeds. The results showed an utmost color removal efficiency (CRE%) and COD removal of 99.78% and 92.86% with an operating cost of US$ 0.028, which is comparatively 98.12% lower than the other conventional electrodes. The treated toxicity test of water was comparable to the toxicity test of tap water. [ABSTRACT FROM AUTHOR]

The analysis of energy consumption in reverse osmosis desalination plants is the most important and relevant factor to study, because this parameter indicates the level of efficiency and competitiveness of the plant. The direct consequence of the high specific energy consumption (SEC) of a desalination plant in the production of water is one of the main obstacles to the exponential expansion of this technology worldwide. The methodological procedure used to carry out the work is based on the analysis of energy consumption, maintenance costs, staff, membranes, and reagents of three desalination plants with a production of more than 23,000 m3/day located in the Canary Islands (Spain); all data are obtained from real analyses collected “in situ” from 2015 to 2018. One of the main objectives of the current research on desalination plants is to reduce the SEC of seawater desalination plants (SWRO), incorporating energy recovery systems (ERS) and high efficiency pumps (HEP), and to implement different operational configurations with the aim of minimizing the energy requirements necessary to obtain a good product quality at minimum production cost.

With increasingly serious environmental problems, a circular economy production system is in urgent needs. This study explores whether green manufacturing (GM) is expensive and how external institutional environmental pressures influence the cost of GM among industrial enterprises in emerging economies. Through an analysis of 10,380 observations of 1470 listed manufacturing firms in the Chinese share market from 2008 to 2015, this paper finds that GM increases operating cost (OC). In addition, the positive relationship between GM and OC is strengthened with reduced pollution level in the local city. Furthermore, synergistic effects of the local pollution level and the local government's pollution information transparency are found. Firms' OC increases more as firms carry out GM when both the local pollution level and pollution information transparency of local government are high, or when the local pollution level and the local government's pollution information transparency are low. [ABSTRACT FROM AUTHOR]

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Background and objectives: Rangeland create various products and services for the users, but currently livestock grazing (forage) is considered the first priority for the exploitation of rangeland. Paying attention to the differents types of services provided by rangeland and determining the economic value of these services helps managers in improving planning and optimal management, creating jobs and increasing the income of users. The purpose of the current research is to investigate the economic value and compare the income of forabge and medicinal production of Jalambadan rangeland in Joveyn County. Methodology: In order to determine the homogeneous areas of vegetation and to study more accurately and easily different parameters related to rangeland production, the rangeland was classified. Then the floristic list of plant types was prepared. Vegetation sampling was done in the representative area of each vegetation type using six 50-meter transects and 1x2 rectangular plots, and the number of plots was estimated to be 368 based on Cochran's formula. In order to calculate the annual plant production in each type of rangeland, the double method was used. Based on this, the amount of fodder production has been estimated in all the plots and only 25% of the plots were cut. In this research, 50% exploitation limit is considered. The estimation of the production of medicinal plants is different according to the organ used for them. Therefore, after identifying medicinal plants and edible organs, the appropriate production estimation method was chosen. Alternative cost method was used for economic estimation of fodder production. Therefore, among the exchangeable plants, the barley plant has been chosen as an alternative product due to its exchangeability in global and local markets. The market price method was used to determine the economic value of medicinal plants. Results: Six plant classes and 119 plant species were identified in the study area. The results showed that the total forage production rangeland was 1180 tons in the entire area of the and the available forage was 590 tons, and the average forage production per hectare of Jalambadan rangeland was 144 kg. The economic value of fodder available in the entire area of pasture is equal to 805,775,000 Tomans. The economic value of each hectare of rangeland in terms of available forage was estimated as 98,241 Tomans. According to the results, the production of available medicinal plants is equal to 256 tons and its economic value is equal to 2,845,000,000 Tomans in 2019. The income of medicinal plants after deducting harvesting costs in 2019 was 1,440,000,000 tomans. The medicinal plants income per hactare estimated 175,672 Tomans. The results show that the exploitation of medicinal plants has 1.78 times higher income than the exploitation of forage plants. Conclusion: Exploitation of medicinal plants is an activity with high economic value and is a good source of income for rangeland users. In addition to forage, as a source of income for the pastoralists, the harvesting of medicinal plants and their processing can be developed to reduce the pressure on the rangeland. [ABSTRACT FROM AUTHOR]

The separation performance, energy demand, and operating costs of electro-coagulation (EC) are compared to conventional chemical coagulation for oil–water separation using a simulated oil-and gas-produced water matrix. An iron-based chemical coagulant and sacrificial iron electrodes are evaluated. Effluent turbidity, chemical oxygen demand (COD), total organic carbon (TOC), and oil and grease (O&G) removal were determined for various coagulant concentrations and reaction times and current densities. Chemical coagulation produced superior turbidity removal when scaled by the total iron dose. At lower iron doses (