Operation Mode Selection Research Articles

Supervisory control strategy for dual battery assisted solar water pumping using a 3-stage interleaved boost converter

This article proposes effective power management and battery protection strategies for a solar photovoltaic (SPV) powered dual-battery supported standalone water pumping approach propelled by a permanent magnet brushless direct current (PMBLDC) motor. A drift-avoidance perturb and observe MPPT algorithm is employed in conjunction with a 3-stage interleaved boost converter (TSIBC) and proposes a switching control scheme to enable double-stage solar photovoltaic generation system (SPGS) to operate at its maximum accessible power point (MPP) irrespective of any variation in climatic condition. The proposed dual battery control scheme (DBCS), which integrates a primary battery with an auxiliary battery, is connected to the 310 V DC link. This dual battery setup utilizes a parallel-active configuration facilitated by two bidirectional DC-DC converters (BDCs). The core idea behind dualization aims to maintain the state of charge (SoC) of the primary battery within upper and lower limits with the help of an auxiliary battery unit and regulate the DC link voltage at 310 V during fluctuations generated in the protection period. This scheme significantly extends the battery's lifespan, achieving an estimated 800 to 1000 cycles by maintaining its depth of discharge (DoD) at a level of 70 %. A centralized power handling unit (CPHU) is integrated for both the BDCs to facilitate the operating mode selection and regulate DC link voltage by alternatively charging/discharging both batteries. This approach enhances overall system efficiency by eliminating the need to oversize the solar array by up to 46 %, which would have been necessary to fully charge both batteries simultaneously. Previously, the DC link voltage regulation relied solely on MPPT control, resulting in significant deviations (up to ±38.43 %) during battery overcharging/deep-discharging (SoC ≥ 90 %/SoC ≤ 20 %). This work proposes a solution using an auxiliary battery controller within the DBCS, achieving near-zero (±0.5 %) DC link voltage deviation under all operating conditions. The effectiveness of the suggested DBCS controller is validated through a time-domain simulation conducted in MATLAB/Simulink, alongside real-time hardware-in-the-loop (HIL) digital simulator using the OPAL-RT platform. The acquired results corroborate enhanced performance for the standalone water pumping system (WPS) and demonstrate a seamless shift from the normal operational mode to battery protection mode, while ensuring steady regulation of the DC link voltage.

SELECTION OF A MRP SYSTEM FOR OIL AND GAS DEPOSITS

A number of serious problems arise in the development of sub-gas zones of oil and gas deposits due to the joint occurrence of oil and gas. The key problem is gas breakthrough from the gas cap to oil wells. This entails an increase in the gas factor (GOR), a rapid and intense decrease in pressure in the gas cap. If there is a reservoir pressure maintenance system or an active aquifer as a result of a decrease in reservoir pressure in the gas cap, oil may be pushed back into it, which leads to a rise in gas-oil contact, jamming of mobile oil in the «dry sandstones» of the gas cap, which in turn leads to a decrease in reserves of mobile oil and a decrease in the oil recovery factor (ORF). All this together allows us to consider oil in the sub-gas zones as hard-to-recover reserves.Preventing and combating the negative consequences of gas breakthrough from the gas cap to oil wells is a complex task and consists of several areas, such as selection of rational drilling of production and injection wells, selection of optimal operating modes for them, use of inflow control devices or performance of repair and isolation work to limit inflow from intervals with gas breakthrough, periodic shutdown of wells to disband gas cones. The ultimate goal of solving these problems is to increase the oil recovery factor and economic efficiency indicators for the development of sub-gas zones.Due to the variety of ways to optimize the development of oil and gas reservoirs, it is not possible to cover them all in one work, therefore, the tasks associated with optimizing the reservoir pressure maintenance system are considered. It is worth noting that in comparison with the development of oil reservoirs, the presence of a gas cap significantly complicates this task due to the lack of analytical solutions for three-phase filtration. For this reason, the selection of the optimal parameters of the reservoir pressure maintenance system is usually carried out either by multivariate calculations in the hydrodynamic model (HDM), or by the method of analogies or the implementation of pilot tests of various approaches.In this study, an approach based on multivariate numerical calculations using the sector model of the development element of the gas zone was used. As a result of calculations, it was shown that when choosing the optimal parameters of the reservoir pressure maintenance system, it is advisable to use a differentiated approach, which consists in the fact that these parameters must be set individually for zones with different ratios of oil-saturated and gas-saturated thicknesses.

Research and application of distributed photovoltaic precise dispatching and control technology

Abstract With the continuous development of the electricity market, the scale of power terminal access continues to expand, and distributed photovoltaic collection and control strategies have become an important research hotspot. The article studies the grid-connected control technology of distributed photovoltaic power plants from grid-connected system architecture, the photovoltaic array operation mode selection, the grid-connected structure between photovoltaic groups, and the series-parallel scheme. It proposes an application method for precise regulation through distributed photovoltaic peak shaving.

Human–Robot Collaboration on a Disassembly-Line Balancing Problem with an Advanced Multiobjective Discrete Bees Algorithm

As resources become increasingly scarce and environmental demands grow, the recycling of products at the end of their lifecycle becomes crucial. Disassembly, as a key stage in the recycling process, plays a decisive role in the sustainability of the entire operation. Advances in automation technology and the integration of Industry 5.0 principles make the balance of human–robot collaborative disassembly lines an important research topic. This study uses disassembly-precedence graphs to clarify disassembly-task information and converts it into a task-precedence matrix. This matrix includes both symmetry and asymmetry, reflecting the dependencies and independencies among disassembly tasks. Based on this, we develop a multiobjective optimisation model that integrates disassembly-task allocation, operation mode selection, and the use of collaborative robots. The objectives are to minimise the number of workstations, the idle rate of the disassembly line, and the energy consumption. Given the asymmetry in disassembly-task attributes, such as the time differences required for disassembling various components and the diverse operation modes, this study employs an evolutionary algorithm to address potential asymmetric optimisation problems. Specifically, we introduce an advanced multi-objective discrete bee algorithm and validate its effectiveness and superiority for solving the disassembly-line balancing problem through a comparative analysis with other algorithms. This research not only provides innovative optimisation strategies for the product-recycling field but also offers valuable experience and reference for the further development of industrial automation and human–robot collaboration.

Novel FPGA clock concept and dual-mode basic logic element

Typically, field programmable gate arrays (FPGAs) use a clock generator, which frequency is calculated based on the worst-case transient. Asynchronous circuits operate on real transient delays, but their design is much more complex. Self-timed (ST) circuits, proposed by D. Muller in the late 50s of the twentieth century, the asynchronous circuit subclass, have built-in means of the transition process completion acknowledging. Thanks to this property, ST circuits are characterized by a wide range of performance in terms of supply voltage and ambient temperature and ensure reliable operation at any logic cell delays determined by the current operating conditions. There are currently no commercially available self-timed FPGAs on the market. And numerous attempts to use traditional synchronous FPGAs and their design tools to create self-timed prototypes have not made it possible to fully realize their potential advantages. This article aims to improve the ST circuit FPGA-implementation efficiency. The Institute of Informatics Problems of the Federal Research Center "Computer Science and Control" of the Russian Academy of Sciences is the major center of competence in the self-timed direction in the Russian Federation. On the topic of joint scientific research with the Perm National Research Polytechnic University, a number of logical cells for ST-FPGA have been previously developed. Target. Formulation of the new FPGA type concept using the operating mode choice, clarification of the proposed logical element's structure and methods of its reconfiguration for a given operating mode, and features of cascading elements of this type for the construction of multi-bit logical elements. The concept of a new type of FPGA with increased flexibility and operating mode selection is proposed. It allows developers to select not only functions and connections, but also to build digital circuits cases with different operating modes using computer-aided design systems: both synchronous and self-timed, or a combination of both. The design of a dual-mode logic element and details of its reconfiguration, as well as scaling issues for bit capacity increase, are also clarified. The practical use of the proposed two-mode basic logic element increases the flexibility of digital equipment projects on FPGAs, which is especially important for critical application areas at the current stage of integrated technology development in the Russian Federation.

Sustainable supply chain operations driven by ‘remanufacturing + product sharing’: operation mode selection and decision optimisation

Consumers’ attention to sustainable production and consumption is promoting innovation in sustainable supply chain operations. We build an extended sustainable supply chain with remanufacturing (and/or) product sharing, and consider three operation modes: Sustainable supply chain operation with remanufacturing but No product Sharing mode (SNS), Sustainable supply chain operation with product sharing but No Remanufacturing mode (SNR), and Sustainable supply chain operation with both product Sharing and Remanufacturing mode (SSR). How does sustainable consumption (i.e. product sharing) affect sustainable production decisions and how to choose the optimal operation mode? Our findings: The SSR mode positively reinforces the sustainability-oriented market segmentation and can be globally optimal with an integrated value-added effect of ‘remanufacturing + product sharing’. From the perspective of total benefit optimisation, when the commission rate of a sharing platform and the proportion of service consumers are higher (lower), the transformation from the SNS mode to the SSR mode (from the SNR mode to the SSR mode) can be the best operational strategy. Maximising total benefits may have a compression effect on product sharing, which can be effectively adjusted by improving consumers’ perceived value of remanufactured products. This study provides guidance for selecting combination strategies for sustainable supply chains in the context of carbon emission reduction.

Climatic applicability of indirect evaporative cooling strategies for data centers in China

Modern digital developments have propelled data center (DC) to prominence, with the cooling requirement being an important driver of its energy consumption. This study explores the climate application potential of indirect evaporative cooling (IEC) technology, which utilizes water evaporation for cooling. The IEC technology is considered as a promising avenue for energy-efficient DC cooling system. This study reveals essential insights for optimizing DC cooling performance by analyzing different IEC operation modes, including dry mode, wet mode, and cascading hybrid mode. The selection of operation mode is closely related to climatic conditions, DC working conditions, and IEC cooling efficiency. Higher DC supply air temperatures extend dry mode cooling hours and decrease cascading hybrid mode hours. It enhances energy savings through better utilization of natural free cooling resources. Elevating IEC cooling efficiency expands dry mode cooling hours while reducing reliance on mechanical cooling, contributing to improved power usage effectiveness (PUE) and energy conservation. The analysis is based on a typical data center and considers representative cities in different climate zones of China, emphasizing the importance of reducing the PUE and energy consumption of the DC by adjusting the DC supply air temperature and improving the IEC cooling efficiency. This work provides a useful reference for customizing DC cooling strategies according to various climate differences, optimizing energy efficiency and promoting sustainable development.

Dynamic rule-based change-over ventilation strategy with weather-responsive air-conditioning setpoints

Recent studies have actively developed dynamic rule-based mixed-mode ventilation (MMV) strategies to manage indoor thermal quality in an energy-efficient manner. Existing research on the dynamic rule-based MMV control has mainly focused on window opening area ratio calculation with fixed setpoints of mechanical operation. However, using fixed setpoints tends to force mechanical operation, though the outdoor temperature is suitable for natural ventilation. For this reason, this study questions whether a rule-based MMV strategy can effectively manage indoor thermal quality and reduce air-conditioning (heating and cooling) load when incorporated with the methods adjusting operation variables of both active and passive systems. To address this research question, this study proposes a dynamic rule-based change-over ventilation strategy integrated with three control components. First, a rule-based control component for adjusting air-conditioning setpoints is developed. Second, an operation mode selection scheme is proposed to decide the appropriate mode for fulfilling thermal demands. Third, a dynamic window opening area ratio function is proposed to provide a sufficient cooling effect to rooms when natural ventilation is required. The proposed strategy integrated with these key components is optimized for each space by non-dominated sorting genetic algorithm II. As a result of the optimization, the proposed strategy reduces 59.77% of the total cooling and heating load against the baseline, which fully operates the building by mechanical systems while ensuring 97.75% of thermally comfortable periods relative to the entire occupied period. Conclusively, this study identified that dynamically adjusting operation thresholds in MMV strategy achieves a substantial load reduction rate and ensures thermal comfort.

Evolutionary Game Analysis on Operation Mode Selection of Big-Science Infrastructures

As big-science infrastructures (BSIs) become the new infrastructure to support the construction of strong science and technology in China, how to choose an operation mode that is more conducive to achieving the construction goals of BSIs has become a current focus issue. The existing literature focuses more on the governance relationship between BSIs and universities or research institutes, while the important role of government has not yet been thoroughly analyzed. This study argues that government plays a fundamental role in the selection of operation modes for BSIs. Therefore, this study builds an evolutionary game model between the government and the contractor based on the perspective of asset specificity by analyzing the practical basis for the strategic choices of the government and the contractor for the operation of BSIs. The model is numerically simulated and analyzed. The research results indicate that the government’s decisions on operation strategies, outsourcing strategies, and the combination of the two significantly affect the strategic choices of the contractor, thereby affecting whether the government can obtain the value of asset specificity of BSIs. The government’s choice of the “independent operation” strategy or the combination “dependent operation + controlled outsourcing” strategy is more conducive to encouraging the contractor to choose the “cooperation” strategy for producing specific value for BSIs. The main contribution of this study is to clarify that the allocation of the government control right is the key factor in obtaining the value of asset specificity of BSIs.

Development of a calculation scheme for selecting the optimal mode of operation of a gas condensate well taking into account the deformation conditions of the formation

To establish premature optimal well operation modes, it is necessary to consider the process of well operation within the framework of ongoing processes in the common reservoir-well hydrodynamic system and take into account the peculiarities of changes in the properties of the gas condensate mixture and the thermobaric conditions of the reservoir in it. Therefore, the object of the study is the operation of a gas condensate well in the event of technological complications in it, which requires the selection of the necessary optimal operating mode to prevent these complications by comprehensively taking into account the factors influencing this process in the “reservoir-well” system.
 The article proposes a calculation scheme for establishing the optimal operating mode of a gas condensate well without the formation of a liquid plug at the bottomhole, taking into account the formation deformation during field development in the depletion mode. The problem is solved by determining the required current working volume of produced gas (as well as condensate), bottomhole and contour values of reservoir pressure, condensate saturation and reservoir porosity. As a result of the study, it was revealed that the determined characteristics of the selected optimal mode of a gas condensate well are significantly affected by a change in the reservoir properties of the reservoir (for example, the permeability of the reservoir), which in turn leads to a change in the optimal working gas flow rate of the well.
 The considered problem has not been previously studied in its full formulation, which is presented in this article, where the solution of the problem under study is achieved taking into account the change in the physical properties of the reservoir fluid and gas, as well as the reservoir properties of the reservoir under conditions of a change in the state of the reservoir system due to emerging deformation processes in the reservoir

Study on Vehicle Supply Chain Operation Mode Selection Based on Battery Leasing and Battery Swapping Services

Considering the impact of the battery leasing service and battery swapping service on the vehicle supply chain operation mode, a vehicle supply chain with a vehicle manufacturer and a battery asset company is investigated. Decision models are formulated in three cases: (a) both battery leasing and battery swapping services are provided by the vehicle manufacturer; (b) both services are provided by the battery asset company; (c) the battery swapping service is provided by the vehicle manufacturer and the battery leasing service by the battery asset company. The optimal decisions for the vehicle manufacturer and the battery asset company in the three cases are derived and compared. The results show that: (1) When the battery leasing increasing time cost coefficient is smaller, it is advisable for the vehicle manufacturer to provide both services; otherwise, the vehicle manufacturer should only provide the battery swapping service. (2) The battery asset company should actively provide-the battery swapping service, since the provision of the battery swapping service can increase its profit. (3) The mode of the vehicle manufacturer providing both services is optimal for the supply chain. (4) When the battery asset company provides battery leasing service, the vehicle manufacturer can “free ride” to enjoy the benefits of the battery asset company extending battery leasing time. (5) With the high cost of new energy vehicles (NEVs) limiting their development in China, extending the battery leasing increasing time is an effective measure to facilitate the diffusion of new energy vehicles (NEVs).

Joint Optimization of Energy and Task Scheduling in Wireless-Powered IRS-Assisted Mobile-Edge Computing Systems

This paper studies the design of an intelligent reflecting surface (IRS)-assisted mobile edge computing (MEC) system, which consists of a mobile user, an IRS equipped with radio-frequency (RF) energy harvesting (EH) circuits, and a hybrid access point (HAP) connected with an MEC server. The IRS is deployed to reflect the users task offloading signals to enhance the received power at HAP, and it needs to harvest energy from the RF signals emitted by the HAP before reflecting signals. To save energy consumption at the user, we first propose a novel MEC protocol, in which the system is enabled to operate in three modes, namely an EH mode, an IRS-assisted task offloading mode, and an IRS-inactive task offloading mode, so that the energy at IRS and the tasks generated at user can be flexibly scheduled within a finite time horizon, depending on channel conditions, IRS energy states and users task queue states. Under the protocol, we optimize the operation mode selection and resource allocation in each mode with a task execution delay constraint. Due to the randomness of wireless channels and task arrivals, the optimization problem is a stochastic programming. To solve this problem, we first transform it into a deterministic one by assuming that noncausal channel state information (CSI) and task state information (TSI) are available, and then derive a practical algorithm where only causal CSI and TSI are required. Simulation results verify that our proposed design can save at most 80% energy consumption as compared with existing baseline schemes.

Optimal operation mode selection of sponge city PPP projects using IFSS-prospect theory and VIKOR approach: a case study in China.

The construction of sponge city (SC) public private partnership (PPP) projects is considered to be a feasible measure to solve the "water problems" in China. To ensure the success of SC PPP projects, how to select an appropriate operation mode for SC PPP projects is an urgent problem to be solved. In this paper, first, the evaluation index system of operation mode is established from the aspects of project characteristics, government capabilities, project benefits, project implementation, and cooperative partnership. Second, the DEMATEL method and entropy method are introduced to overcome the drawbacks of a single method, and the combination weights are calculated by game theory. Finally, the decision-making model based on intuitionistic fuzzy soft set (IFSS)-prospect theory and VIKOR approach is constructed to select operation mode for SC PPP projects. In this paper, the framework is applied to select an operation mode for the Qingshan demonstration zone project, and its feasibility and effectiveness are verified through sensitivity analysis and comparative analysis. The results show that BOT is the optimal operation mode for SC PPP projects, and government capabilities and project implementation are critical factors to be considered when selecting an operation mode. This study can provide guidance to the government in the OMS of SC PPP projects and improve the sustainability of the projects.

Dynamic time warping–based feature selection method for foot gesture cobot operation mode selection

Dynamic time warping–based feature selection method for foot gesture cobot operation mode selection

The influence of ultrasonic processing on the structure and electrophysical properties of fruit in combined drying

The intensification of ultrasonic vibrations for the processing of agricultural products is becoming increasingly important in the food industry, as it can reduce energy consumption for the dehydration of raw materials. The research aims to study the effect of sonication on the change of electrophysical parameters and structure of apple raw materials in the process of combined drying using direct electric heating. Using scanning electron microscopy, images of the surface structure of dried apple samples were obtained at different combinations of sonication duration and methods of heat supply to the raw material during the drying process. Based on the experimental studies, the dependences of the current flowing through the sample in the process of combined drying using direct electric heating on the duration of raw material processing in an ultrasonic bath were obtained. The influence of preliminary sonication on the maximum values of the current strength during direct electric heating was determined. The dependences of changes in the resistivity of apple samples during dehydration at different pretreatment durations were investigated. The effect of ultrasound on the initial resistivity of apples, the duration of electro-plasmolysis, and the resistivity values at which the maximum values of the direct electric heating current are observed were determined. The results of the experiments show that the pretreatment of raw materials in an ultrasonic bath can reduce the peak current values by up to 27%. The initial values of the resistivity of the raw material after sonication are reduced by 7.8-13.8% compared to the control samples. The obtained images of the dried fruit surfaces showed an increase in the porosity and roughness of the samples. The obtained results of experimental studies can become a prerequisite for the development of an energy-efficient technical means of ultrasonic processing of fruit and vegetable raw materials before drying and the selection of optimal operating modes

Event-Triggered Online Scheduling for Industrial-Integrated Energy System

Sound scheduling and allocation of multi-energy media is of paramount significance for reducing energy consumption and improving operation efficiency in an industrial integrated energy system of a steel industrial park, and the online optimization solution of various scheduling events can be regarded as the prerequisite for such challenging tasks. Thus, a novel granular-driven extended particle swarm optimization with meta-cognitive component in terms of what-to-learn, how-to-learn, and when-to-learn, termed as MC-GEPSO, is proposed in this study, which were realized by the observation, learning and selection of operation mode described by granularity. Furthermore, an adaptive interval type-2 fuzzy systembased on autonomous fuzzy rule learning mechanism is reported for achieving the selection of granularity described by equipment operation performance, and the multiple-objective optimizations of online-scheduling can be solved by GEPSO. The performance of the proposed MC-GEPSO is experimentally validated by a number of industry study cases, where the proposed approach outperforms manual scheduling in aspect of operation cost, operation efficiency, and carbon emissions.

Multi‐sided? Operation mode of sharing economy enterprises

AbstractTurning to the theoretical methods of two‐sided markets, we analyze the operation mode selection of the sharing economy. Considering the interactions of the operating enterprise, resource suppliers (basic service providers), value‐added service providers, and consumers, we show that the selection of one‐sided mode, two‐sided mode, or multi‐sided mode depends on enterprise service quality, pricing power and cross‐group externalities of sharing economy service, utility evaluation and access cost of the value‐added service. Further, we give a theoretical explanation of the operation mode evolution in China's online car‐hailing market and put forward two specific multi‐sided platform development paths.

High-Powered RF SOI Switch With Fast Switching Time for TDD Mobile Applications

This paper presents a fast switching and high-powered single-pole double-throw (SPDT) switch for RF switch circuits, such as TRx antenna switches and frequency band (or operation mode) selection switches in mobile handset applications. For fast switching time and performances of the RF switch, we proposed a novel method that can “selectively” control the impedance of a gate biasing circuit (“high” or “low” impedance). The proposed SPDT switch use the low impedance of the gate biasing circuit for fast switching time and use the high impedance of the gate biasing circuit to avoid the degradation of the insertion loss and harmonics. The proposed SPDT switch has no additional bias and no large payment for size consumption. According to measurement results, the turn-on switching time of the proposed SPDT switch was <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.35~\mu \text{s}$ </tex-math></inline-formula> (at 2 GHz). The insertion loss, isolation, and return loss at 2 GHz were 0.16 dB, 47.1 dB, and 24 dB respectively. 2nd and 3rd harmonic levels at 25 dBm input power at 2 GHz were −88.7 dBm and −78.9 dBm, respectively. Power handling capability was 39.5 dBm of input power at 2 GHz. The designed SPDT switch was implemented in a 0.13- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> partially depleted silicon-on-insulator (PD-SOI) process.

Design of a High-to-Low Voltage, Low-Power, Isolated DC/DC Converter for EV Applications

The design of a low-cost 800–12 V, 4 W isolated dc/dc converter for automotive applications is investigated. Such a converter is required to supply tiny systems directly from the high-voltage battery of an electric vehicle. In particular, a selected topology based on a multilevel flying-capacitor stage is analyzed. The converter operating mode selection is studied and simulation results reveal the interest of operating at the limit of the zero voltage switching (ZVS) mode. The design of a planar transformer adapted to the application is described. Design considerations of an IC brick that includes the main blocks required to control the power stage are discussed. The performances of a 4-W prototype with two transformer designs validate the choice of the operating mode. The peak efficiency is 87.4% which confirms the interest of the selected approach compared to existing solutions.

A Review of Urban Rail Transit PPP Research

To relieve the pressure of government investment and high-cost operation in major infrastructure projects, the PPP (Public-Private Partnership) is widely used in transportation engineering projects, especially urban rail projects. In this paper, we use Excel and Citespace software to categorize the research hotspots and analyze the trend changes to visualize the cooperation network analysis by searching 217 academic papers in core journals of Zhiwang, CSI, EI, CSSCI, and CSCD by keywords "PPP and transportation". Nowadays, the research of PPP-Transportation Engineering mainly focuses on the construction of risk management systems, performance evaluation systems, subsidy scheme decision systems, and operation mode selection methods for the whole life cycle of urban rail projects. This paper also analyzes the one-sidedness and research blind spots in the field of PPP_transportation, and provides research ideas for building a complete knowledge system and application development in the field of PPP-transportation in the future.