Search Results (81)

In the context of building a new type of power system, the optimal operation of high-proportion new-energy distribution networks (HNEDNs) is a current hot topic. In this paper, a stochastic distribution robust optimization method for HNEDNs that considers energy-storage refinement modeling is proposed. First, an energy-storage lifetime loss model based on the rainfall-counting method is constructed, and then an optimal operation model of an HNEDN considering energy storage refinement modeling is constructed, aiming to minimize the total operation cost while taking into account the energy cost and the penalty cost of abandoning wind and solar power. Then, a source-load uncertainty model of HNEDN is constructed based on the Wasserstein distance and conditional value at risk (CvaR) theory, and the HNEDN optimization model is reconstructed based on the stochastic distribution robust optimization method; based on this, the multiple linearization technique is introduced to approximate the reconstructed model, which aims to both reduce the difficulty in solving the model and ensure the quality of the solution. Finally, the modified IEEE 33-bus power distribution system is used as an example for case analysis, and the simulation results show that the method presented in this paper, through reducing the loss of life in the battery storage device, can reduce the average daily energy storage depreciation cost compared to an HNEDN optimization method that does not take the energy storage life loss into account; this, in turn, reduces the total operating cost of the system. In addition, the stochastic distribution robust optimization method used in this paper can adaptively adjust the economy and robustness of the HNEDN operation strategy according to the confidence level and the available historical sample data on new energy-output prediction errors to obtain the optimal HNEDN operation strategy when compared with other uncertainty treatment methods. Full article

This paper develops a nonlinear optimization model for the optimal allocation of labor and investment resources in a three-sector open economy. The model is based on the Cobb–Douglas production function and incorporates sectoral interdependencies, capital depreciation, trade balances, and import quotas. The resource allocation problem is formalized as a constrained optimization task, solved analytically using the Lagrange multipliers method and numerically via the golden section search. The model is calibrated using real statistical data from Kazakhstan (2010–2022), an open resource-exporting economy. The results identify structural thresholds that define balanced growth conditions and resource-efficient configurations. Compared to existing studies, the proposed model uniquely integrates external trade constraints with analytical solvability, filling a methodological gap in the literature. The developed framework is suitable for medium-term planning under stable external conditions and enables sensitivity analysis under alternative scenarios such as sanctions or price shocks. Limitations include the assumption of stationarity and the absence of dynamic or stochastic features. Future research will focus on dynamic extensions and applications in other open economies. Full article

This study evaluates the impact of grape variety and harvesting method—manual versus mechanized—on must composition, wine quality, and economic performance in the Târnave viticultural area of Romania. Four grape varieties—Pinot Noir, Sauvignon Blanc, Fetească Regală, and Muscat Ottonel—were analyzed. Manual harvesting increased reducing sugars by 4.3–5.1 g/L and decreased titratable acidity by 0.6–0.8 g/L, particularly in Pinot Noir and Muscat Ottonel. Alcohol content was higher by 0.4–0.6 vol% in manually harvested samples, and dry extract increased by 1.0–1.3 g/L. Mechanized harvesting raised catechin concentrations by 15–19 mg/L due to enhanced skin maceration, but also slightly elevated volatile acidity (by ~0.1 g/L). From an economic perspective, labor cost was reduced from 480 lei/ton (approx. EUR 96) for manual harvesting to 120 lei/ton (approx. EUR 24) with mechanization. Fuel and maintenance costs for mechanized equipment averaged 85 lei/ha (EUR 17), and equipment depreciation was estimated at 100 lei/ton (EUR 20). The total harvesting cost per ton decreased from 480–520 lei to 300–320 lei (approx. EUR 96 to EUR 64), representing a ~38% reduction. The study supports a hybrid approach: manual harvesting for sensitive or premium cultivars, and mechanization for cost-efficient, large-scale production, aligning wine quality goals with economic sustainability. Full article

Glycerin has a similar energy value to corn and can partially replace it. However, there is a need to find the ideal level for using glycerin in pig feed without negatively interfering with performance parameters. The objective of this study was to determine the digestibility of glycerin through a mixture (MIX) or inserted on top of feed (ONTOP) using chromium indicator (Cr) and total collection (TC) methods. Ten barrows weighed 42.63 ± 4.23 kg in a 2 × 2 + 1 factorial scheme, with two forms of inclusion of the test ingredient (MIX or ONTOP), two digestibility methods (Cr or TC), and a basal diet (BD). The experimental design was completely randomized, and the evaluation period was used as split-plots, with two repetitions per period, totaling four repetitions per diet. The DE and ME values for glycerin were 3443 and 3356 kcal/kg (by the TC method) and 3411 and 3293 kcal/kg (by the Cr method), respectively (p < 0.05). There was no difference in MIX or ONTOP (p > 0.05), except for the digestibility coefficient (DC) of ethereal extract (p < 0.05). The DC and energy values obtained by Cr were lower than those obtained by TC. The inclusion of the test ingredients in the MIX and ONTOP forms did not present any difference, whereas Cr depreciated the nutritional value of glycerin for pigs. Full article

In the wine production chain, climate change affects the yields and quality of the wine. Several studies have found that high temperatures have a significant impact on the value of wine production. In this context, adaptation measures represent a good practice to face the damage caused by negative climatic events. Since these practices have a cost, this study aims to provide an estimate of economic convenience for their adoption, using the methodology developed within the LIFE Adaptation in Agriculture project. In this paper, four measures used in winemaking processes and useful for reducing damage induced from climatic events were analyzed. The findings show that the adaptation measures considered in the wine sector usually have an initial investment cost of medium/high. Large farms, due to their size and resources, can opt for one or more measures with a greater ease of cost depreciation. Overall, the analysis shows that although the implementation of measures presents medium/high investment costs, it is always appropriate to assess the specific business case, even where the results indicate a lower degree of cost-effectiveness. When deciding on the adoption of measures, it should be kept in mind that costs depend not only on farm characteristics but also on the choice of implementation method and staff training and specific public subsidies. Full article

While achieving common prosperity necessitates a focus on the efficiency and equity of the primary income distribution, income inequality persists in China. As a critical tax incentive mechanism, China’s Accelerated Depreciation Policy (ADP) of fixed assets not only promotes important changes in corporate productivity and production methods but also significantly influences the primary income distribution within enterprises. However, current research offers a limited understanding of the importance of the ADP in the primary income distribution. Given that the core of the primary distribution lies in adjusting the labor income share, we regard 2014’s ADP as an exogenous “quasi-natural experiment”. After theoretically analyzing this policy’s effect on the labor income share of enterprises, our use of difference in differences (DID) validates our theoretical expectations with respect to China’s A-share listed companies during 2010–2022. The results show that the ADP can significantly increase enterprises’ labor income share; all hypotheses proved to be robust. The analysis of mechanisms shows that the ADP mainly affects the labor income share as it upgrades the corporate human capital structure as well as rent-sharing. Analyzing for heterogeneity, we find that positive effects due to the ADP affecting the labor income share are more prominent among private enterprises, medium and small-sized firms, companies with high financing constraints, capital-intensive industries, manufacturing enterprises, and those with a high level of skilled labor. The conclusions of this study contribute to uncovering the impacts of the ADP on income distribution, offering a clearer identification of particular mechanisms explaining the ADP’s effect on the labor income share. It holds significant theoretical value for understanding the micro-mechanisms of economic impacts generated by relevant policies. Furthermore, it provides policy insights in achieving common prosperity. Full article

The increasing requirement for distillates, accompanied by higher quantities of heavy crude oil in world production, has positioned gas oil hydrocracking as one of the most significant processes in refineries. In the petrochemical industry, hydrocracking is an essential process that converts heavy hydrocarbons into lighter and more valuable products such as LPG (liquefied petroleum gas), diesel, kerosene, light naphtha, and heavy naphtha. This method uses hydrogen and a catalyst to break down the gas oil feedstock through hydrogenation and hydrocracking reactions. However, the gas oil hydrocracking process faces significant technical, economic, and financial obstacles that must be overcome to reveal its full potential. In this study, a computer-assisted technical–economic evaluation and an evaluation of the technical–economic resilience of the gas oil hydrocracking process at an industrial scale was carried out. Twelve technical–economic and three financial indicators were evaluated to identify this type of process’s current commercial status and to analyze possible economic performance parameter optimizations. The economic indicators listed include gross profit (GP), profitability after taxes (PAT), economic potential (EP), cumulative cash flow (CCF), payback period (PBP), depreciable payback period (DPBP), return on investment (ROI), internal rate of return (IRR), net present value (NPV), annual cost/revenues (ACR), break-even point (BEP), and on-stream efficiency at the BEP. On the other hand, the financial indicators proposed by the methodology are earnings before taxes (EBT), earnings before interest and taxes (EBIT), and earnings before interest, taxes, depreciation, and amortization (EBITDA). The technical–economic resilience of the process was also evaluated, considering the costs of raw materials, the market prices of the products, and processing capacity. The gas oil hydrocracking plant described, with a useful life of 20 years and a processing capacity of 1,937,247.91 tonnes per year, achieved a gross profit (GP) of USD 58.97 million and a return after tax (PAT) of USD 39.77 million for the first year, operating at maximum capacity. The results indicated that the process is attractive under a commercial approach, presenting a net present value (NPV) of USD 68.87 million at the end of the last year of operation and a cumulative cash flow (CCF) of less than one year⁻¹ (0.34 years⁻¹) for the first year at full processing capacity, which shows that in this process, variable costs have more weight on the economic indicators than fixed costs. Full article

Acquired long-term tangible assets of water management companies generate depreciation costs during operation. The cost item naturally reduces the profit/loss and income tax deduction and, at the same time, creates financial space for the future restoration of this property, reinvestment by being able to include it in the unit price of water and/or sewerage charge rates if certain rules are met. On the basis of these legislative rules, it follows that property financed by subsidies cannot be depreciated in this way, i.e., cannot generate funds for future reinvestment. The contribution aims to present a methodical procedure for deciding on a strategy for the development of the profit/loss of enterprises when “predicted” (modeled) depreciation of fixed assets acquired from subsidies is included in the model, with a focus on the indicator of financial performance—profitability of sales. Basic methods and selected indicators from ratio indicator methods used in financial analysis were used in the methodical procedure. The methodological procedure, which was developed on the basis of a case study as part of a research report for a selected water management enterprise, was further implemented and verified on a sample of water management enterprises, which have almost a 50% share in the value of all assets in the form of infrastructure assets in the Czech Republic. The output of the article is the fact that when “predicted” (modeled) depreciation is included in the profit/loss, the profitability of sales decreases. The study shows that there is up to a 15% change in the profitability of sales. The contribution of the article is a proven methodological procedure that takes into account the generation of profit/loss with regard to the necessary reinvestment of assets acquired with subsidies. This strategy can generally be used by all companies that acquire assets from public subsidy sources. Full article

Clostridium species are known for their impact on animal and human health, but also for the spoilage of foodstuffs. Their spores contaminate milk and result in germination and gas production, the latter being particularly evident in the cheeses that suffer severe depreciation. To address this issue, the Primary Production Department of the IZSLER institute in Brescia, Italy conducts the Most Probable Number (MPN) method on bovine milk samples collected from Northern Italian dairies between 2004 and 2023. This approach leverages two semi-quantitative protocols, S2 and S3, to detect Clostridium species spore forms upon customer request. Here, we would like to present an a-posteriori analysis on the results of the S2 and S3 protocols. The goal of this study is to highlight the differences between these two methods and provide evidence of the actual decrease in Clostridium species in raw cow milk over a 20-year period. Our analysis shows that client demand for S2 has progressively decreased, while S3’s has remained constant, and both protocols reveal a significant reduction in positives; furthermore, S3’s greater sensitivity made it more responsive to environmental changes. This highlights the necessity of choosing the appropriate testing protocol that accounts for both regulatory standards and environmental factors. Overall, our findings underscore the importance of continued monitoring to manage Clostridium species contamination and ensure milk quality. Full article

Throughout this article, an alternative depreciation method for electric vehicles (EVs) is presented, addressing the challenge of information asymmetry—a common issue in secondary markets. The proposed method is contrasted with traditional models, such as the Straight-Line Method (SLM), the Declining Balance Method, and the Sum-of-Years Digits (SYD) method, as these classic approaches fail to adequately consider key factors such as mileage and secondary aspects like battery degradation and rapid technological obsolescence, which critically impact the residual value of used EVs. The presented approach employs an adverse selection model that incorporates buyers’ and sellers’ perceptions of vehicle quality from the information recorded on e-commerce platforms, improving the depreciation estimation. The results show that the proposed method offers greater accuracy by leveraging asymmetric information extracted from web portals. Specifically, the method identifies a characteristic intersection point, marking the moment when the model aligns most closely with the data obtained through traditional methods in terms of precision. The analysis through the density of price estimations by vehicle model year indicates that, beyond 1.8 months, the proposed model provides more reliable results than traditional methods. The proposed model allows buyers to identify undervalued assets and sellers to obtain a fair market value, mitigating the risks associated with adverse selection, reducing uncertainty, and increasing market transparency and trust. It fosters equitable pricing between buyers and sellers by addressing the implications of adverse selection, where sellers—possessing more information about the vehicle’s condition than buyers—can dominate market transactions. This model restores balance by ensuring fairer valuation based on vehicle usage, primarily addressing the lack of critical data available on e-commerce platforms, such as battery certifications, among others. Full article

Assessing the new quality productive forces (NQPF) of new energy vehicle (NEV) companies is crucial for promoting the sustainable development of the NEV industry. This paper systematically evaluated and analyzed the NQPF of Chinese listed NEV companies from 2018 to 2022 using a novel multi-criteria decision analysis (MCDA) model. To address limitations in traditional MCDA models, such as unbalanced weight distribution, insufficient ranking differentiation, and incomplete identification of key influencing factors, this study introduced a new model, IDOCRIW-PROBID (integrated determination of objective criteria weights—preference ranking on the basis of ideal-average distance). First, an evaluation index system tailored to NEV companies’ NQPF was developed. Then, the IDOCRIW method was used to objectively assign weights to the indicators, enhancing the scientific rigor of the weight distribution. The PROBID method was employed to rank companies based on their NQPF, identifying differences between them. Additionally, an obstacle degree model was introduced to analyze key influencing factors, compensating for the traditional MCDA model’s limitations in this regard. The results showed, first, that the proposed IDOCRIW-PROBID model has a high degree of consistency with the classical Entropy-TOPSIS (technique for order of preference by similarity to ideal solution) model in terms of ranking the results (correlation coefficient = 0.91), and that IDOCRIW-PROBID offers higher differentiation compared to other MCDA models, validating its reliability and superiority. Second, during the study period, the development levels of NQPF in Chinese listed NEV companies varied significantly, with most companies at a low level of development and showing a downward trend, indicating that companies face considerable challenges in improving their NQPF. Third, the obstacle degree analysis revealed that R&D lease fees, R&D depreciation and amortization, and direct R&D investment were the primary factors hindering NQPF growth. This research provides theoretical support and decision-making insights for strategic optimization in NEV companies and informs government policy formulation. Full article

The motivation for this research was the desire to disclose the social nature of the financial risks of global companies: the authors attempted a scientific explanation of the influence of corporate social responsibility, which is manifested through the preservation and creation of additional jobs, on the financial risks of global companies. The research aims to establish the interdependence between financial risks and sustainable employment in global companies. This goal is achieved using the SEM (structural equation modeling) method based on corporate statistics from the Fortune “Global 500” rankings for 2021–2023. As a result, the consequences of global companies’ CSR (corporate social responsibility) practices in personnel management and financial risk management are modeled and described through quantitative and qualitative patterns. The established regularities proved that for developed and developing countries, the larger the number of employees, the lower the financial risks of global companies—the risk of a decrease in profitability, the risk of loss of profit, and the risk of depreciation of assets. The main conclusion is that there is a close systemic relationship between the financial risks of global companies and their workforce size, suggesting that CSR is key to highly effective financial risk management. A clear distinction between the practices of financial risk management through CSR in developed and developing countries forms the basis of the theoretical significance of the research results. The authors provide recommendations to improve the current practice of financial risk management in global companies by integrating it more closely with personnel management practices, highlighting their managerial relevance. It is proposed that corporate strategies for global companies in developed countries should focus on reducing the risk of declining profitability, as CSR has the most pronounced and consistent impact on this particular financial risk. In developing countries, corporate strategies are recommended to be structured by diversifying the areas of CSR application, with the most promising in financial risk management being the reduction in asset depreciation risk and the reduction in profitability risk. The findings of this research have practical significance because they enhance the predictability of CSR activities of global companies and open up opportunities for highly accurate forecasting of the financial risk implications of ensuring sustainable employment by global companies, considering the specificities of developed and developing countries. Full article

Introduction: Over the years, welding fumes’ harmful effects have been demonstrated countless times in the scientific literature. Recently, studies in the field have shown an increasing interest in the negative consequences that these fumes may have on the tissues of the oral cavity. Materials & method: The current study aimed to investigate the impact that welding fumes have on the structure of human dental enamel by analyzing the microhardness of the dental enamel in 15 extracted human teeth, after various exposure times, using the Vickers method. Results: The results obtained after 48, 96, 168, and 336 h of direct exposure of the extracted specimens to the welding fumes show a statistically significant increase in the depreciation of the dental enamel’s microhardness, related to the duration of exposure (p < 0.05). An average of 305 Vickers units was observed at the longest exposure time, 336 h, in the present study, whereas in the control group, the microhardness analysis showed an average of 327 Vickers units. Full article

To address the complexity and high computational burden in the design of drip irrigation networks, the Jaya algorithm is utilized to study factors affecting project costs, including equipment and pipeline depreciation and the operation and management costs of the irrigation area. A mathematical model of synchronization optimal design of pipe layout and pipe diameter selection in a drip irrigation network system with constraints on pipe diameter, flow velocity, and pipe pressure is established. Using an irrigation district in Xinjiang, China, as an example, the Jaya algorithm optimization design program was run independently 50 times, and the relative deviation of each optimization result from the optimal solution was calculated. The results show that the annual cost per unit area o is reduced to 635.99 RMB/hm², a 25.34% reduction compared to the original engineering program, and the investment-saving effect is obvious. The relative deviation is controlled within 3%, which shows that the algorithm has stable convergence performance and can meet the requirements of actual engineering design. The Jaya algorithm eliminates the need for parameter tuning, and it excels in cost savings, algorithm stability, and computational accuracy, making it an effective method for the single-objective optimization design of drip irrigation networks. Full article

Persistent exchange rate depreciation and its debilitating effects on rising inflation have remained a concern in Nigeria. This article explores the effects of exchange rate pass-through on producer prices, consumer prices, export prices, import prices and the Taylor rule from 2000 to 2023, using quarterly data and adopting threshold autoregression and self-exciting smooth threshold regression methods. The findings suggest that there are non-linearities in the way that exchange rate depreciation affects prices in Nigeria. Furthermore, the findings suggest a threshold of 5 percent depreciation. Two sub-sample analyses corroborate the main findings, showing that a threshold of 5 percent is the optimum benchmark if demand and supply are not to be weakened. At this level or below, the effects of exchange rate depreciation on inflation are much lower, even though prices will rise. However, above this benchmark, the effects of depreciation on inflation are much larger, weakening consumer demand for both imported and domestic goods as well as producer supply of both exported and domestic goods and services in the economy. This result implies that an average exchange rate depreciation not higher than 5 percent within a quarter is reasonable if the Nigerian economy is to remain competitive both domestically and globally. Finally, the results suggest that the exchange rate pass-through to prices is considerably higher in Nigeria below the threshold, while it overshoots for producer prices, export prices, and import prices above the threshold. To keep inflation in check, this paper suggests that the monetary authorities should try to keep exchange rate depreciation below the established thresholds, while also considering adjusting the policy rate to take into account the exchange rate depreciation thresholds in order to keep domestic prices stable. Full article