Operative Loss Research Articles

Grey wolf optimizer for the design optimization of a DC-DC boost converter

Design optimization of a DC-DC boost converters for minimizing overall operational losses is the problem under study. The optimum design contains selecting the best value of circuit inductance, capacitance, and switching frequency for the continuous conduction mode (CCM) operation. The design constraints selected are the current ripple content, ripple content of voltage, and bandwidth for operation in CCM. Grey wolf optimizer (GWO) algorithm is implemented for the boost DC-DC converter’s optimal design. The comparative investigation of algorithms reveals that GWO outperforms other established optimization algorithms like the particle swarm optimization (PSO), moth flame optimization (MFO) algorithm, simulated annealing (SA) and firefly algorithm (FFA) in terms of convergence time, computational effort, and the minimized system losses while finding the most efficient design of the converter. Parametric study on statistical performance indicates that the GWO algorithm outperforms the rest of the optimization algorithms on comparing with previously reported results. The optimized results obtained in the current work provides and improved converter design with reduction in the power loss in the optimized design of the converter by over 15% from previously reported works.

The potential impacts of the digital revolution on the operational risk profiles of banks

Society is undergoing a digital revolution. This is altering the business profiles of banks in terms of their systems, processes, controls and usage of third parties; their competitive landscape, ie competition from both digitising incumbents and new BigTech and FinTech entrants; and the behaviours of stakeholders, ranging from customers to cyber-criminals. This digital revolution is amplifying some of their existing risks, while also creating new risks, eg the potential for artificial intelligence (AI) tools to change behaviours over time (AI model drift). Some of these changes in operational risk profile will be transient, as they are associated with digital transformation, while others will be both ongoing and characterised by a high degree of dynamism. In this digitised endstate higher frequency/lower value human errors, may be replaced by lower frequency/higher impact systemic losses, arising from both catastrophic and silent failures. The influence of the digital revolution spans almost all of the Basel operational risk event categories, and may also lead to the enhancement of some controls (eg surveillance), while others may be undermined (eg by voice-spoofing). There is no silver bullet to mitigate these risks; instead, a portfolio of existing control frameworks need to be enhanced, including the following: change management; model risk management; third party vendor management; business continuity management, disaster recovery and operational resilience; and cybersecurity, with new controls required to address the new risks associated with AI. This will be a key factor in the operational risk losses of banks over the next decade.

The Origin of Mineral Waste from Constanta Port and the Necessity to Introduce it into the Circular Economy

Abstract Constanta Port is the largest port on the Black Sea. Only here are operated the largest ships that have access through the Bosporus and Dardanelles straits. Of these, the largest tonnage is operated in berths 80 – 84 belonging to COMVEX SA. In the port there are also terminals for operating bulk cargo belonging to SOCEP and Minmetal. During the operation of ships, transport and storage of bulk cargo, basic activities of the terminal, losses of bulk materials occur, which periodically collected are waste because they no longer meet the original characteristics of the goods. According to GD 111/2002, these quantities of materials are called technological losses and are a mixture of iron ore, bauxite, coke and coal. The mineral components of this waste, defined as mineral waste, are from the handled materials, and which are of the highest quality. This quantity cannot be shipped to customers and therefore the respective quantities of goods represent operating and storage losses. Periodically, this mixture must be removed so that the land surfaces on which the stacks of materials are formed remain clean. The production of mineral waste is closely linked to the activity of the Ore Terminal. The mineral mixture from cleaning operations is stored in temporary storage dumps. In addition to the fact that these quantities of goods represent losses, they also represent an impact on the environment. The storage of this waste involves occupying important, available, adjacent areas and sometimes production areas. This also has implications for the operator's handling capacity as it requires additional operations involving energy consumption, labour consumption, vehicle use, etc. In conclusion, this scenario negatively affects the economic and social development of the company operating with bulk materials. Due to the specificity of the bulk cargo handling terminal, between 1991 and until now, significant quantities of mineral waste valued at approx. 650.000 t. Similar wastes are a characteristic of large ports, which transit such bulk goods, such as: Rotterdam – EMO operator – Netherlands, Dunkirk and Sollac sur Mer – France, Tianjin – China.

The TCJA and Domestic Corporate Tax Rates

We study changes in tax positions for U.S. C corporations following passage of the 2017 tax legislation commonly known as the Tax Cuts and Jobs Act (TCJA). While existing research has focused primarily on publicly traded companies, data limitations have prevented more holistic analyses of the corporate sector. Using a representative sample of U.S. corporate tax returns, we highlight how trends in effective tax rates (ETRs) and exposure to the legislation’s main provisions varied for public, private, multinational, domestic, and large versus small firms. We document several novel facts, including that ETRs increased on average for privately held, domestic firms and for firms in the bottom 90% of the firm sales distribution after TCJA. In contrast, public, multinational, and large firms saw substantial ETR cuts on average. We find that firms' pre-TCJA exposure to changes in the corporate tax rate and treatment of net operating losses have the strongest correlation with post-TCJA ETR changes. Overall, the analysis underscores the divergent impacts of TCJA on different firm types and illuminates the economic scope and relative significance of TCJA’s myriad provisions.

Adaptation to the new energy side of the configuration of energy storage optimization analysis

Energy storage technology is the key to achieving a high proportion of new energy generation, but the current optimization analysis of renewable energy side configuration of energy storage technology is not comprehensive enough and does not consider different application scenarios and operating conditions. In order to better select the appropriate energy storage technology and formulate the corresponding policy, this paper takes the western region of China as an example, and uses the particle swarm algorithm to determine the optimal energy storage configuration scheme; finally, comparing with the traditional scheme, the proposed optimization scheme takes into full consideration the stochastic nature of the wind and light power and the load in the microgrid, and reduces the cost of the energy storage configuration. Also, the grid operation loss is reduced and the economy of the grid operation is improved.

Distribution network reconfiguration using improved colonial competition optimization algorithm

The implementation of a distribution network is generally aimed at increasing system efficiency, increasing the level of optimal operation, increasing the stability of the power grid, reducing blackouts, and increasing reliability. By providing general definitions of networks and the principles of optimal operation and reliability indicators and loss reduction in power systems, the general principles of network control and optimal operation are presented and finally, practical ideas for the optimal operation of power networks with The approach of increasing system reliability and maximum productivity of distributed production resources is presented. In the presence of a distribution network and by using appropriate control algorithms, it is possible to optimize the power network in different working conditions; After the occurrence of a disturbance in the network, the power system is exposed to instability. The network can restore the stability of the system by communicating critical conditions to the subscribers as well as rearranging the network structure and shut down the least number of subscribers. Implementation of a distribution network in general with the aim of increasing system efficiency, increasing the level of optimal exploitation, increasing the stability of the power grid, reducing outages and increasing reliability.

Stochastic MILP Model for Merging EV Charging Stations with Active Distribution System Expansion Planning by considering Uncertainties

Radial Power Distribution Networks (PDNs) often suffer from limited reliability, flexibility, and efficiency, leading to service interruptions. Planning for radial PDNs is essential to enhance redundancy resilience, reduce disruptions, and improve overall efficiency. However, traditional PDN planning methods have become obsolete due to the proliferation of Distributed Generation (DG) resources and energy storage systems. Additionally, the rise of Electric Vehicles (EVs) demands sophisticated charging infrastructure planning. This article presents a Mixed-Integer Linear Programming (MILP) model for joint expansion planning of PDN and Electric Vehicle Charging Stations (EVCSs). The model takes into account the construction or reinforcement of substations and circuits, along with the integration of EVs, the installation of DGs, and the placement of capacitor banks, all regarded as traditional conventional expansion options alternatives. To address uncertainties associated with DG generation, conventional loads, and EV demand, our model identifies optimal installation and asset locations. We formulate this as a stochastic scenario-based program with chance constraints for Power Distribution Network Expansion Planning (PDNEP), minimizing investment, operational, and energy loss cost costs over a planning horizon. Through two deterministic and stochastic approaches, encompassing six case studies on an 18-node test system, we evaluate the effectiveness of our model. Results are further validated on a 54-node system, confirming the model’s robustness. Notably, the numerical findings underscore the substantial cost reduction achieved by including EVCSs in the stochastic expansion planning approach, demonstrating its cost-effectiveness. In case study I, where all EVs charge at home during peak hours, it’s the worst case for the PDN. The 54-node system, more complex, demands longer computational time. In the 18-node system, costs improve from 9.97% (case study II) to 3.96% (case study VI) versus the worst-case (case I). In the 54-node system, improvements range from 10.47% (case study II) to 1.40% (case study VI). As a result, In comparative analyses against deterministic and stochastic approaches, our model consistently outperforms in diverse test case studies. The proposed model’s adaptability to address uncertainties underscores its suitability for solving the PDNEP problem in PND.

A navigation method for paddy field management based on seedlings coordinate information

Compared to tillage, transplanting, and harvesting operations in paddy fields, field management operations such as spraying and weeding require completing tasks along the rice seedling rows to minimize seedling damage and reduce operational losses. Visual navigation, as a commonly used navigation method, can identify rice seedling rows, but it is susceptible to complicated paddy field environments. To address these challenges, our study combines UAV (unmanned aerial vehicle) surveying technology with the YOLOv5s object detection algorithm and proposes a navigation method for paddy field management based on seedling coordinate information. Firstly, the YOLOv5s object detection algorithm was used to identify and locate rice seedling points in the UAV image, and a coordinate transformation model was established to extract the geographic coordinates of the seedling points. Secondly, in order to classify the recognized seedling points into different seedling rows, a classification algorithm was proposed, and the improved RANSAC algorithm further promoted the classification effect. Once again, to obtain a smooth navigation path for agricultural machinery navigation, B-spline curves were used to approximate the classified seedling points. Finally, the generated navigation paths were written into the navigation controller, and the navigation performance was tested on flat ground and paddy fields using a vehicle platform. The results of the flat ground test indicated that different bending degrees have a significant impact on the lateral error. When the bending degree was large, the maximum lateral error was less than 7 cm, and when the bending degree was small, the maximum lateral error was less than 4 cm. The navigation accuracy of RMS in the flat ground test was 2.7 cm. In the paddy field experiment, due to the influence of loose soil surfaces and potholes, the maximum lateral error was about 16 cm. The navigation accuracy of RMS in the paddy field experiment was 5.9 cm, which can meet the operational requirements. The experimental results show that the proposed navigation method can achieve automatic navigation of agricultural machinery along curved rice seedling rows under complex paddy field environments, such as light change, seedling shortage, uneven road surfaces, and curved seeding rows.

Разработка мощного пологого пласта с выпуском угля подкровельной толщи роботизированным комплексом

Introduction. When developing coal deposits using underground method, the greatest success was achieved for the seams with the thickness of up to 7 m by means of complex mechanization in one layer. The productivity of a cleared face reaches 6–8 thousand tons per day. A method of coal extraction from the top coal layer is used to mine seams of greater thickness. The limiting factor is the inability to control of the extraction process and, as a result, significant operational losses. Objective. The research aims to develop promising technologies for efficient and safe mining of thick flat coal seams using a robotic complex with controlled extraction from the top coal layer. Methods. The research is based on the analogy method. Results. By closing the gates installed on the extended sides of the line conveyor sections during the operation of the coal cutterloader and opening them during the release of coal, penetration of the loosened coal into the “pockets” of the support sections is eliminated. This reduces the operational loss of coal, the likelihood of “floating” sections of the support, as well as risks of emergencies. Due to the presence of an additional bunker on the side of the mined-out space, the coal from the top layer is collected, temporarily withheld, and then gravity fed into the outlet opening. Elimination of the advance preparation of the top coal layer in the area above the planned break-down chamber prevents man-induced discontinuities inside the rock mass above the breakdown chamber, which increases its stability. Construction of the break-down chamber with an inclination against the working face provides a sequential introduction of the support sections into the break-down chamber, one at a time, which allows timely preparation and release of coal.

The Influence of the Directors Boaards and Operational Profit and Loss on Tax Avoidance (Empirical Study of Sub-Oil and Natural Gas Companies Listed on the Indonesia Stock Exchange 2017-2022)

The phenomenon of taxation in Indonesia is Indonesia's low tax ratio in 2021 which is recorded at only 9.11%, a low tax ratio indicates a high level of tax avoidance in a country. This study aims to determine the influence of the Board of Directors and Operational Profit and Loss on Tax Avoidance. Tax avoidance in this study is measured by the Cash Effective Tax Rate. This study used a sample of oil and gas companies listed on the Indonesia Stock Exchange during 2017 – 2022 using a purposive sampling method. The analytical method used is quantitative descriptive analysis. The results of this study indicate that the proxy for the board of directors, operational profit and loss has no effect on tax avoidance

Pendampingan Rebranding Kemasan Produk Sayuran Segar (Keran Payung Bambu) Kelompok Wanita di RPTRA Payung Tunas Teratai dan Bambu Petung

According to a survey conducted by the Bank of Indonesia (BI) in July 2021, the Economic Conditions Index (IKE) was recorded at 67.1. IKE is composed of three components, namely the Current Income Index, Job Availability Index, and Durable Goods Purchase Index. On the other hand, the rapid expansion of internet access in Indonesia has been influencing consumer shopping trends, especially among those aged 25-38. Through various e-commerce platforms, consumers can access a wide range of products relevant to their daily lives, such as fresh fruits and vegetables. Therefore, it is essential to empower the community through robust and healthy entrepreneurial activities to support the local economy. This can be achieved through various means, including mentorship and training. The role of the community in the RPTRA Payung Tunas Teratai and Bambu Petung areas, through independent business activities, cannot rely on external entities. Hence, the development of micro and small-scale businesses accessible to the community is necessary. The community is encouraged to utilize available land for agriculture, including in RPTRA Payung Tunas Teratai and Bambu Petung. The types of vegetables produced are diverse, including water spinach, long beans, mustard greens, pumpkin, and more. The goal of these activities is to enhance marketing and income through rebranding. Special thanks to the Directorate General of Higher Education, Research, and Technology, Ministry of Education, Culture, Research, and Technology, for providing research funding in 2023, RPTRA Payung Tunas Teratai and RPTRA Bambu Petung, as well as the involvement of the Manpower, Transmigration, and Energy Office, Sub-district Office of Tourism and Creative Economy in East Jakarta, Satpel PPUKM, Satpel KPKP, and Satpel Dinsos in the Cipayung District, who participated and coordinated in the series of research activities. The activities took place on Friday, September 8, 2023, in RPTRA Payung Tunas Teratai in the Cipayung Sub-district and on Wednesday, September 12, 2023, in RPTRA Bambu Petung in the Bambu Apus Sub-district. A total of 79 participants attended, divided into two groups in RPTRA Payung Tunas Teratai and Bambu Petung. The results of this research were increased income, skills, and empowerment of partners. The research outputs include a national accredited journal publication (published in PAMAS, Sinta 4), electronic media coverage (Radar), video documentation (Website and YouTube URINDO), and additional intellectual property (Flyer) with certification. The impact of these activities on the achievement of higher education Key Performance Indicators (IKU) includes students gaining experience outside the campus (IKU-2), faculty members engaging in off-campus activities (IKU-3), and Faculty Work Results Used by the Community (IKU-5). Through these research activities, the beneficiary community members received information on how to process and package vegetables to prolong their shelf life and increase their market value. This series of research activities has proven to be highly beneficial, reducing losses for business operators through appropriate product packaging methods to maintain product freshness, durability, and appeal.
 
 Keywords: Rebranding, Fresh Vegetables, Women's Groups

Investigation of active voltage support control approach of DC distribution networks based on virtual inertia coordination

AbstractDC distribution networks (DCDNs) possess the advantages of high power efficiency, low operation loss, and favourable control flexibility, and are regarded as an essential form of future power distribution systems. In order to increase the voltage transient performance of DCDNs against disturbances, this paper proposes a methodology for realising the active voltage support control of DCDNs based on virtual inertia coordination. Firstly, the impact of the inertia of DCDNs towards the transient voltage change is analysed, and the active voltage support mechanism considering the variable droop inertia control and virtual DC motor inertia (VDCMI) control is explored. Then, a time sequence coordination strategy based on the voltage grading of DCDNs is developed, and an adaptive inertia coefficient is designed to achieve the inertia adjustment in terms of the voltage sag and recovery processes. Using MATLAB/Simulink, a detailed model of the double‐terminal DCDNs is created to check the efficacy of the proposed approach. Different voltage disturbance scenarios are imitated, and the comparative simulations demonstrate that the proposed approach can fully utilise the inertia potential of the DCDNs to suppress the voltage sag and smooth the voltage recovery procedure. The proposed method's validity and feasibility can be well validated.The cover image is based on the Original Article Investigation of active voltage support control approach of DC distribution networks based on virtual inertia coordination by Lei Chen et al., https://doi.org/10.1049/esi2.12123.

Analisis Risiko Operasional dengan Menggunakan Metode Failure Mode and Effect Analysis pada PT Hasjrat Abadi Manado

This research uses qualitative methods with a case study approach. Data analysis was carried out using the Failure Mode and Effect Analysis method. This study aims to analyze the operational risk of Toyota product sales at PT Hasjrat Abadi Manado. Data shows that several things that cause operational losses are an increase in indent cancellations, the presence of deadstock goods, slow moving products, the availability of car stock that consumers are interested in less, the existence of laping in the process of indenting Toyota products. The difference in the hospitalization of Toyota parts stock, so researchers focused this study on operational activities for Toyota product sales. The results of this study show the results of risk identification using the Risk Breakdown Structure method of operational risk at PT Hasjrat Abadi Manado specifically for Toyota products (Cars and Spare Parts) obtained a total of 45 risks identified for the entire of each risk indicator. Internal process risk indicators have 22 sub-risks, external risk indicators have 12 sub-risks, HR risk indicators have 9 sub-risks, and system risk indicators have 2 sub-risks. Critical risks obtained from FMEA calculations that need recommendation actions are units not supplied, sales to agencies are not paid, sales using customer indent money, and network disruptions.

Impact of climate change on berthing areas in ports of the Balearic Islands: adaptation measures

Climate change generates impacts on coastal areas due to sea-level rise and potential modifications in wave and storm surge patterns. Since harbours are located in littoral areas, they will experience different impacts associated to such processes. In this paper, the effects of climate change on port berthing areas in terms of operability are quantified. The study is focused on the ports of the Balearic Islands (Western Mediterranean Sea) and analyses the loss of operability due to the reduction of freeboard in berthing structures and the potential variation in agitation within these harbours during the 21st century, considering two different climate scenarios (RCP4.5 and RCP8.5) and two-time horizons (2045 and 2100). In addition, adaptation measures to address such impacts are proposed and their cost estimated. The results indicate that climate change will not generate significant changes in wave agitation due to negligible variations in wave patterns under future scenarios. On the contrary, sea-level rise will cause huge increases of inoperability for berthing structures due to insufficient freeboard: 10.5% under RCP4.5 or 20.5% under RCP8.5 in 2045, increasing to 57.1% (RCP4.5) and even 83.2% (RCP8.5) in 2100.

Utilization of Stockwell Transform and Random Forest Algorithm for Efficient Detection and Classification of Power Quality Disturbances

Power quality disturbances (PQDs) can lead to significant operational and financial losses in power systems. Accurate detection and classification of PQDs are essential for maintaining power quality and preventing power system failures. This research article introduces an innovative approach for the precise detection and classification of single- and multiple-state power quality disturbances (PQDs) using the Stockwell transform (ST) and a random forest classifier. To create realistic PQD signals, seventeen distinct classes are generated in accordance with IEEE Standard 1159, employing mathematical equations implemented in MATLAB software. The ST is employed to extract relevant features from the PQD signals, which are subsequently utilized as input for the random forest classifier. The classifier employs bootstrapping sampling to generate multiple training sets from the original dataset. Each training set is used to construct a decision tree by recursively partitioning the data based on significant features. To mitigate overfitting and enhance robustness, a random subset of features is selected at each node of the decision tree, thereby reducing tree correlation. The performance of the random forest classifier is compared with other widely utilized machine learning classifiers. The results exhibit the efficacy of the proposed approach in accurately detecting and classifying PQ events, highlighting its superiority over alternative methods.

Outcomes of 1-Stage Versus 2-Stage Revisions After Hip Prosthetic Joint Infection

Background: Prosthetic joint infections (PJIs) are significant complications of total joint arthroplasties. The incidence of this dangerous complication is expected to rise, but there is not a unanimous solution. Two-stage surgical revisions are the traditional gold standard of treatment, but recent literature suggests that 1-stage revisions can be equally effective. A comparison of the outcomes of 2-stage revisions vs. 1-stage revisions has not been thoroughly investigated. This systematic review and meta-analysis were designed to compare the outcomes of 2-stage exchanges vs. 1-stage exchanges in the treatments of hip PJI based on comparison studies. Methods: MEDLINE, Embase, and Cochrane were searched for relevant studies that compared the effectiveness and outcomes of 1-stage and 2-stage procedures from January 2000 to May 2023. Keywords relating to hip PJI were used, and comparison studies of 1-stage vs. 2-stage procedures that reported patient characteristics and outcomes including success rates, rates of reinfection, or other outcomes such as functional outcomes (e.g., mean Harris hip scores), infection-free survival, and blood loss were included. Statistical analysis for this study was conducted using Review Manager 5.4 with a standard p-value of ≤ 0.05 for statistical significance. Results: Fifteen articles and 1,017 patients were included in the meta-analysis. One-stage revision procedures (320 patients) were found to have greater success rates (i.e., lower rates of reinfection) than 2-stage revisions (697 patients) (p = 0.04). One-stage revisions (184 patients) had shorter durations of operation and less blood loss than 2-stage revisions (90 patients) (p < 0.05). Conclusion: One-stage revision procedures are associated with lower reinfection rates, blood loss, and durations of operation compared with 2-stage revisions. Level of Evidence: I.

A Model of Risk Management Strategy at Banks in their Operational Activities

By partnering with the business, the operational-risk discipline can create a more secure and profitable institution. Successful banks embrace risks while developing powerful mechanisms to prevent or manage risk and stay ahead. This study is devoted to the problems of improving the banking risk management, taking into account the new regulatory and technological requirements based on the use of modern technology and combining the latest achievements in numerical mathematics, statistics and information technology. Focusing on literature and by conducting a case study on operational risk management on one of largest retail banks, this paper aims on answering how operational risk management can be improved by implicating risk governance and internal control frameworks. It was concluded that although improvements have taken place in how operational risks are being managed, there is still room for improvements. An intersection of risk type and business/functional area of focus, prioritized based on the business environment is critical when fulfilling this life cycle of risk management activities. When too linear, the steps are not agile enough, so the cycle needs to be performed on a micro-level and aggregated for macro-level insights/risk decision-making. The suggested model outlines the understanding of the safe and prudent management of risks under the current prudential framework. It also demonstrates the ability of appropriate operations management techniques to reduce operational risk losses in the banking industry significantly.

Operational loss estimation in irrigation canals by integrating hydraulic simulation and crop growth modeling

Operational loss estimation in irrigation canals by integrating hydraulic simulation and crop growth modeling

A comprehensive study of techniques utilized for structural health monitoring of oil and gas pipelines

An extensive network of pipelines is extensively employed worldwide to carry oil and gas fluids over millions of kilometers. The pipeline channel was constructed to resist environmental dynamic loading conditions to provide safe and reliable oil and gas fluids transportation from the production well sites to depot stations installed at sea coastlines. However, pipeline infrastructure damages such as fractures, cracks, leakages, etc., are significant sources of economic losses in pipeline operations. Moreover, pipeline failures can cause considerable ecological catastrophes, human deaths, and financial loss. Important research initiatives have been committed to establishing pipeline breach detection and localization using various techniques to avoid these threats and maintain a secure and dependable pipeline network. This paper reviews different state-of-the-art damage detection methods and their recent advancement with a case study explaining the application of light detection and ranging for pipeline damage detection. The pros and cons of diverse damage detection methods in pipeline networks are also discussed. Research gaps for pipeline damage detection systems are also provided for better understanding and future research.

Scenario analysis loss of heat removal from the spent fuel pool on nuclear power plant

The spent nuclear fuel storage system is designed to store and cool spent fuel for several years taking into account scheduled reloads and unloading of the entire core accumulated after use in a nuclear reactor. It consists of special pools or containers where spent fuel is placed for temporary storage before final treatment or disposal. These systems provide safe and efficient storage of spent fuel to prevent radioactive material from leaking into the environment and minimize risks to human health and the natural environment. The events that occurred during the Fukushima nuclear disaster on March 11, 2011, underscored the importance of safe storage of spent fuel in the spent fuel storage pool. Storage safety has therefore become a key aspect in this area. This article describes the heat sink loss calculations for the analytical substantiation of the emergency response instructions for the shutdown state of the Armenian NPP power unit No.2 using the RELAP5/Mod3.2 computer code. The initiating event in the event of loss of heat removal from the spent fuel pool is considered. The analysis of nuclear safety in the course of the development of a beyond design basis accident with a long NPP blackout was carried out in relation to the spent fuel pool of a power unit with a reactor plant WWER-440 (project V-270). The radiation consequences are estimated. The article provides calculations of the following accidents to determine the necessary actions of the operator: loss of heat removal from the spent fuel pool without operator action and loss of heat removal from the spent fuel pool from the organizations of subsequent make-up of the spent fuel pool with a boron cleaning pump (2NBO-2). The calculations are based on boundary and initial conditions corresponding to the assumptions of the «better estimate».