Reasonable Scheme Research Articles

Refined standards for simulating UV–vis absorption spectra of acceptors in organic solar cells by TD-DFT

Photoexcitation property of acceptor plays a vital role to understand fundamental physical process of acceptor excitation in organic solar cells (OSCs), which should be described at a reliable level and characterized by ultraviolet-visible (UV–vis) absorption spectra. Generally, adiabatic linear-response time-dependent density functional theory (LR-TD-DFT) as a suitable framework, which requires to select exchange correlation functionals (XCFs) and basis sets to concentrate the approximation of models, is widely recognized. However, selecting reliable theoretical methods tends to consume computational cost and time, and optimal selections have not yet reached general standards. Herein, a systematic investigation including XCF, basis set, calculation density, solvation effect, and full width at half maximum (FWHM) was undertaken to quantify the photoexcitation properties of typical fullerene acceptors (FAs) and non-fullerene acceptors (NFAs). The results reveal that maximum absorption wavelength (λmax) of NFAs is strongly correlated with the fraction of “exact” Hartree-Fock exchange (EEX), thus establishing selection standards. Moreover, calculation density is the primary factor to ensure the integrity of spectra. This work provides reasonable schemes for characterization conditions, which further lays foundation for the reliability of theoretical calculations that will help to advance the theoretical characterization of optical properties of organic materials.

Gate Optimization Analysis of Injection Molding for Mobile Phone Panel Based on Moldflow and Drop Simulation

Aiming at the gate design problem of a mobile phone panel, the plastic forming analysis software Moldflow and drop simulation were used to optimize the gate design. Six different gate design schemes were compared and studied, and the weld lines positions and injection molding results under each gate scheme were analyzed.Through the simulation analysis of the falling process of the mobile phone panel by the display dynamics analysis software ANSYS Workbench LS-DYNA, five analysis schemes were set according to the falling angle, and the stress distribution at the weld lines positions of the mobile phone panel in each scheme was studied. The reasonable gate scheme was given by synthesizing the force condition, the mold flow analysis and the drop simulation results of the mobile phone panel in use. Based on the results of die flow analysis and drop simulation the optimal gate design scheme 2 is found, and the weld line position avoids the lower part of the elliptical hole, which is the weak part of the structure. The research results had certain reference significance for the optimization of injection process of plastic products.

A controller deployment scheme in 5G-IoT network based on SDN

Due to the wide spread of 5G networks, network users have higher requirements for communication delays. Software-defined network is a new paradigm of decoupling the control logic from packet forwarding devices. We can reduce communication latency in the network by optimizing the location of the controller and improve the communication performance of the network. In this paper, the controller deployment problem of multi-network area is studied in order to reduce the average communication latency. In order to solve this problem, we proposed an optimized DPC algorithm. Specifically, on the basis of DPC algorithm we quoted the idea of triangular stability from the BeeDPC algorithm, and introduced SC measurement indicators, the degree of separation between sub-network regions and the degree of aggregation within the sub-network region, so as to divide the network region more reasonably. At the same time, we have break out of the constraints in the DPC algorithm and introduced closeness centrality to get a more reasonable placement scheme and reduced the limitations of the DPC algorithm. Simulation results have shown that the optimized DPC algorithm can effectively reduce the average delay between the control layer and the data layer, improve the network performance, and enhance network stability and reliability.

Performance evaluation for solar combined gas heating system

A test platform for solar combined gas heating system was designed and established in Tianjin, control strategy for system operation was determined to meet domestic heating and hot water supply needs; basing on performance test, a series of evaluation indexes in energy saving, environmental protection and economic benefit for system operation were put forward; selecting 6 typical heating days in winter, the weight of each evaluation index in the series was analyzed by entropy weight method, it was found that, the index of renewable energy guarantee rate occupied the maximum weight, the indexes of static investment payback period and cost-benefit ratio occupied the minimum ones with the same weight ratio, finally a comprehensive evaluation method for system performance under different operating conditions was established. This study provided a comprehensive evaluation for system operation across meteorological states and operating conditions, so that making actual operation and testing data comparable and providing a reasonable evaluation scheme for the optimal configuration and operation of the system.

Wind Turbine Lubrication Based on Parallel Control of Multiple Factors

The lubrication needs of wind turbines vary with the operating conditions. To provide a dynamic lubrication scheme for wind turbines under variable conditions, this paper designs a dynamically adjustable lubrication scheme through parallel control of multiple influencing factors. Based on mid- and long-term loads, the proposed scheme fully considers the influence of various sudden changes in addition to slowly changing factors like load, operating hours, and speed, such as to dynamically adjust the injection flow as per the specific operating condition of the turbine. The ideal lubrication effect was tracked through the adjustment of the injection flow or injection time, and used to determine the optimal dynamic lubrication control strategy during turbine operation. The proposed control strategy overcomes the defects of the traditional fixed-time fixed-flow lubrication approach, and provides reasonable on-demand lubrication schemes for wind turbines in different operating conditions. The on-demand injection of lubricant prevents under- or over-lubrication, reduces the rate of mechanical failure, and extends the service life of wind turbines. Suffice it to say that the proposed control strategy can lower power generation cost and save energy, making wind turbines more profitable.

Power Control for Full-Duplex Device-to-Device Underlaid Cellular Networks: A Stackelberg Game Approach

In spectrum sharing cognitive radio networks, unauthorized users (secondary users) are allowed to use the spectrum of authorized users (primary users) to improve spectrum utilization. Due to limited spectrum resources, how to formulate a reasonable spectrum allocation scheme is very important. As a mathematical analysis tool, game theory can solve the problem of resource allocation well. In recent years, it has been applied to the research of resource allocation in spectrum sharing networks by some literatures. In a cellular network consisting of multiple cellular users and full-duplex end-to-end communication users D2D (device-to-device), the self-interference caused by full-duplex communication and the interference caused by the D2D users to the cellular users will significantly reduce system throughput. In order to reduce the interference in the network, this paper introduces a power control algorithm based on Stackelberg game, which sets the cellular users and D2D users as the leaders and followers, respectively. The cellular users and the D2D users compete with each other to minimize the cost, and we propose new utility functions. We build an optimization problem under the outage probability constraint and power constraint and the transmission power of the users is obtained by using the Lagrangian dual decomposition method. The simulation results show that the proposed game algorithm improves network performance compared with other existing schemes.

An enhanced multi‐objective differential evolution algorithm for dynamic environmental economic dispatch of power system with wind power

AbstractDynamic environmental economic dispatch (DEED) with wind power is an important extension of the classical environmental economic dispatch (EED) problem, which could provide reasonable scheduling scheme to minimize the pollution emission and economic cost at the same time. In this study, the combined dynamic scheduling of thermal power and wind power is carried out with pollutant emission and economic cost as optimization objectives; meanwhile, the valve‐point effect, power balance, ramp rate, and other constraints are taken into consideration. In order to solve the DEED problem, an enhanced multi‐objective differential evolution algorithm (EMODE) is proposed, which adopts the superiority of feasible solution (SF) and nondominated sorting (NDS) two selection strategies to improve the optimization effect. The suggested algorithm combines the total constraint violation and penalty function to deal with various constraints, due to different constraint techniques could be effective during different stages of searching process, and this method could ensure that each individual in the Pareto front (PF) is feasible. The results show that the proposed algorithm can deal with DEED problem with wind power effectively, and provide better dynamic scheduling scheme for power system.

Tangible and intangible incentives of key executives of management bodies of regions and districts: Modeling and assessment

Subject. This article explores the relationship between financial and non-financial motivations of top executives of State administration agencies in the context of aligning the interests of board-level managers and the general public. Objectives. The article aims to create a model for assessing the financial and non-financial incentives of top managers of the administration bodies of regions and districts to develop a reasonable reward and recognition scheme. Methods. For the study, we used a multi-objective genetic algorithm. Results. The article presents a developed model for assessing the financial and non-financial incentives of top managers of the administration bodies of regions and districts. As well, it presents certain results of an analysis of board-level managers' incentives use through applying the model. Relevance. The results obtained can be useful to government agencies to develop a reasonable system of financial and non-financial incentives of the agencies' top leadership.

A novel classification regression method for gridded electric power consumption estimation in China

Spatially explicit information on electric power consumption (EPC) is crucial for effective electricity allocation and utilization. Many studies have estimated fine-scale spatial EPC based on remotely sensed nighttime light (NTL). However, the spatial non-stationary relationship between EPC and NTL at prefectural level tends to be overlooked in existing literature. In this study, a classification regression method to estimate the gridded EPC in China based on imaging NTL via a Visible Infrared Imaging Radiometer Suite (VIIRS) was described. In addition, owing to some inherent omissions in the VIIRS NTL data, the study has employed the cubic Hermite interpolation to produce a more appropriate NTL dataset for estimation. The proposed method was compared with ordinary least squares (OLS) and geographically weighted regression (GWR) approaches. The results showed that our proposed method outperformed OLS and GWR in relative error (RE) and mean absolute percentage error (MAPE). The desirable results benefited mainly from a reasonable classification scheme that fully considered the spatial non-stationary relationship between EPC and NTL. Thus, the analysis suggested that the proposed classification regression method would enhance the accuracy of the gridded EPC estimation and provide a valuable reference predictive model for electricity consumption.

Analysis of nonpoint source pollution load in Ulansuhai Nur basin

The aim of this study is to explore the specific situation of nonpoint source pollution in Ulansuhai Nur basin, so as to provide reasonable and scientific pollution control and water area protection schemes. According to the socioeconomic statistics and water quality information of Ulansuhai Nur basin from 2008 to 2019, taking chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) as the control indicators, the sources of nonpoint source pollutants (urban domestic sewage, livestock breeding, rural domestic area pollution, rural agricultural production area pollution, and aquaculture pollution) are analyzed. And the amount of each pollution source into the lake is analyzed according to the discharge coefficient and inflow coefficient. The inflow amount and the changing trends of COD, TN, and TP discharged from each pollution source are compared and analyzed, and the main sources of pollution for each control indicator are explored. The causes of water pollution in Ulansuhai Nur basin in recent 10 years are analyzed so as to provide theoretical basis for water pollution control in Ulansuhai Nur basin. The results show that the COD and TN intake in the Ulansuhai Nur basin increase year by year between 2008 and 2019, the pollution load is serious, and it mainly comes from urban domestic sewage and rural agricultural production pollution; the TP intake shows a trend of increasing first and then gradually decreasing, and the inflow amount of pollutants is relatively small and is mainly from livestock breeding; which indicate that the load of nonpoint source pollution in Ulansuhai Nur basin has exceeded the capacity of the lake greatly, causing serious harm to water quality, so proper measures should be taken to control it.

Numerical Simulation of Shallow Geothermal Field in Operating of a Ground Source Heat Pump System—A Case Study in Nan Cha Village, Ping Gu District, Beijing

The inefficient use of single energy and cold accumulation in the shallow geothermal field seriously affect the efficient operation of the ground source heat pump system (GSHPS). The operation of solar-assisted GSHPS can effectively solve the above problems. In this paper, a shallow geothermal utilization project in Nan cha Village, Ping Gu District of Beijing, is chosen as the study area. A three-dimensional numerical model of groundwater flow and heat transfer considering ambient temperature and backfill materials is established, and the level of model integration and validation are novel features of this paper. The thermal response test data in summer and winter conditions are used to validate the model. The results show that increasing hydraulic gradient has a positive impact on the heat exchange. The mixture of sand and barite powder is recognized as a more efficient and economical backfill material. The changes of thermal influence radius, heat balance, and shallow geothermal field are simulated and analyzed by three schemes. It is demonstrated that the thermal influence radius is 5 m, 3.9 m and 3.9 m for Scheme 1, Scheme 2 and Scheme 3, respectively. The ground temperature is always lower than the initial formation temperature in Scheme 1 and Scheme 2; however, under Scheme 3 it is higher than the initial values. The closer the hole wall is, the larger the difference between the initial formation temperature and the ground temperature, and vice versa. The thermal equilibrium of Scheme 1, Scheme 2 and Scheme 3 is −728 × 106 KJ, −269 × 106 KJ and +514 × 106 KJ. Through comprehensive analysis of the above three factors, Scheme 3 is regarded as the most reasonable scheme for a solar system to assist GSHPS.

China’s initial allocation of interprovincial carbon emission rights considering historical carbon transfers: Program design and efficiency evaluation

Establishing a fair and reasonable initial allocation scheme for carbon emission rights is a prerequisite for the efficient and stable operation of the carbon market and an important guarantee for China to achieve its emission reduction target. This study considers the historical transfer of carbon emissions and measures the cumulative net carbon emissions of China's provinces based on the principle of consumer responsibility. It draws up an initial allocation plan for carbon emission rights in China's provinces in 2020, based on the principles of equity, efficiency, and sustainability. The carbon emission and carbon intensity efficiencies of the provinces under this distribution scheme were also evaluated. The results show that the historical net carbon export area mainly consists of energy-intensive provinces and economically underdeveloped poor and remote provinces. Additionally, the historical net carbon import area mainly consists of energy-starved and economically developed provinces. Provinces with high-value ecological services (Xinjiang, Heilongjiang, and Inner Mongolia) or with large economies and dense populations (Shandong, Guangdong, and Sichuan) will receive higher carbon emission rights, while those with developed economies (Shanghai, Beijing, and Tianjin) will receive lower carbon emission rights. Provinces with a good ecological environment (Inner Mongolia, Heilongjiang, and Xinjiang) as well as certain economically underdeveloped western provinces (Chongqing, Sichuan, and Yunnan) will have abundant carbon space in the future. Provinces with rapid economic development (Beijing, Shanghai, and Jiangsu) and resource-based provinces (Shanxi and Liaoning) with a high historical carbon output have little carbon space. Considering the historical carbon transfer, the carbon emission rights allocation system will benefit resource-based industrial provinces (Shanxi, Inner Mongolia, and Liaoning) and less developed western provinces (Shaanxi, Ningxia, and Xinjiang) in improving their carbon emission efficiency. This study provides a new research idea for formulating a more equitable and efficient allocation scheme for carbon emission rights.

Parking Space Reservation Behavior of Car Travelers from the Perspective of Bounded Rationality: A Case Study of Nanchang City, China

For travelers who inevitably use motor vehicles, in the case of limited parking spaces, reserving parking spaces in destination in advance helps reduce the time and emissions of searching for parking spaces and alleviate road traffic pressure. From the perspective of bounded rationality, this paper comprehensively considers the impact of traveler’s personal attributes and behavioral characteristics on parking reservations. The data processing analysis shows that the traveler’s age, gender, monthly income, and other characteristics have a certain impact on the parking reservation choice behavior. Reservation price is the key factor affecting the parking reservation policy. Travelers show different value perceptions of the reserved price of parking spaces, and this process has been verified to be roughly the same as the prospect theoretical model. As the reference point for highest reservation price becomes larger, travelers tend to choose to pay less than the ideal reservation price and become more sensitive to losses. It can be found from the model functions and survey data that the ideal reserved parking space price in the survey area is 5 yuan per hour which equals the normal parking fee, and the ideal parking reservation time is less than 2 hours. The research results provide a basis for formulating reasonable parking reservation schemes and parking policies.

Surrounding rock control technology for the fault passing of mining face by removing gangue in advance from excavation roadways

This study presents a new technology for passing through faults quickly by removing gangue in advance from driving roadways of working faces; this technology has the advantages of short moving time and good coal quality during fault passing. However, in practice, driving roadways are affected by mining pressure during the driving and mining period; thus, roadway support is difficult. This study aims to develop appropriate support for driving roadways, not only to ensure the stability of the roadway and satisfy the space requirements for the working face when it passes through the fault but also to reduce the strength of the rock pillars in the roadway. In this manner, the shearer can directly reduce the working strength during the period of fault passing. In this study, UDEC numerical simulation software is used to explore the size of rock pillars and the parameters of bolt support. In addition, the supporting effect of ordinary, high-strength prestressed, and high-strength prestressed yielding bolts is compared. On the basis of the simulation results, a reasonable control scheme of surrounding rock in advanced driving roadways is proposed. Moreover, the successful application of the technology in field practice shows the remarkable effect of this scheme on the surrounding rock control when passing faults. Thus, this study provides some references for surrounding rock control during the fault passing of the mining face.

Some Thoughts on the Design for At-grade Intersections of Urban Road

Road intersections, as nodes in the road network, are the key to improving operational efficiency. Extensive practice has shown that a reasonable design of the intersection scheme will help to release the road capacity and improve the smoothness of traffic for various participants including motor vehicles and slow traffic. This paper, based on relevant domestic and foreign codes and other achievements, has put forward some thoughts on the design principles, design ideas and follow-up development of intersection engineering, aiming to provide a certain reference for relevant management, analysis and design work. Urban roads are the lifeblood of urban economic life and one of the important signs of development of urbanization. In the process that urban municipal roads are continuously being built into a network and road traffic demand is continuously being tapped and released, the “throat” effect of at-grade intersections of the road is constantly emerging. At the at-grade intersections, under the background of low traffic speed and a large number of people flows and vehicle flows interweaving at the intersection, designing a scientific and reasonable traffic organization scheme for intersections will help to improve the efficiency of the intersection and even the road section. However, the change in the design space brought about by the property line planning concepts such as “narrow roads, dense road networks” and “street all-factor planning and design”, as well as the trend of increasing complexity of urban underground pipelines and underground facilities, have put forward new requirements for the design of road intersections. But at the same time, for some intersection schemes designed according to the new design concept, due to the lack of a clear basis for examination and approval, there is a space for discussion. In view of this, it is necessary to think about and sort out the planning and design process of at-grade intersections, and on the basis of fully examining the three stages of planning design, engineering design and management control design, to put forward suggestions on planning design in the new era and new situation. The author is mainly engaged in the stage of engineering design, so this paper will put forward some thoughts on the at-grade intersection design from the perspective of engineering design and management control design.

Research on Mining Scheme Design Based on 3D Real Scene Model

Reasonable mining scheme is of great significance for safety and efficiency of mining activity and environmental protection. In view of the limitation that the traditional mine surveying and mapping method can’t provide accurate terrain data for the mining scheme design, moreover, the common mining design software can’t be combined with the 3D real scene mining situation for scheme analysis and evaluation, this paper proposed a design method based on 3D real scene model by combining the UAV Remote sensing technology and 3D geographic information technology. This method can make the mining design agree with the demand of mining efficiency and environmental protection, improving the rationality of mining design.

Correction to: Phase-field modeling of fracture in heterogeneous materials: jump conditions, convergence and crack propagation

In this contribution, a variational diffuse modeling framework for cracks in heterogeneous media is presented. A static order parameter smoothly bridges the discontinuity at material interfaces, while an evolving phase-field captures the regularized crack. The key novelty is the combination of a strain energy split with a partial rank-I relaxation in the vicinity of the diffuse interface. The former is necessary to account for physically meaningful crack kinematics like crack closure, the latter ensures the mechanical jump conditions throughout the diffuse region. The model is verified by a convergence study, where a circular bi-material disc with and without a crack is subjected to radial loads. For the uncracked case, analytical solutions are taken as reference. In a second step, the model is applied to crack propagation, where a meaningful influence on crack branching is observed, that underlines the necessity of a reasonable homogenization scheme. The presented model is particularly relevant for the combination of any variational strain energy split in the fracture phase-field model with a diffuse modeling approach for material heterogeneities.

A Data-Driven Timetable Optimization of Urban Bus Line Based on Multi-Objective Genetic Algorithm

Reasonable bus timetable can reduce the operating costs of bus company and improve the quality of bus services. A data-driven method is proposed to optimize bus timetable in this study. Firstly, a bi-objective optimization model is constructed considering minimize the total waiting time of passengers and the departure times of bus company. Then, Global Positioning System (GPS) trajectories of buses and passenger information collected from Smart Card are fused and applied to calculate the key parameters or variables in optimization model, including time-dependent travel time, bus dwell time and passenger volume. Finally, by adopting a specific coding scheme, an improved Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is designed to quickly search Pareto optimal solutions. Furthermore, an experiment is conducted in Beijing city from one bus line to validate the effectiveness of the proposed method. Comparing with empirical scheduling method and traditional single-objective optimization base on GA, the results show that the proposed model could quickly provide high-quality and reasonable timetable schemes for the administrator in urban transit system.

Phase-field modeling of fracture in heterogeneous materials: jump conditions, convergence and crack propagation

In this contribution, a variational diffuse modeling framework for cracks in heterogeneous media is presented. A static order parameter smoothly bridges the discontinuity at material interfaces, while an evolving phase-field captures the regularized crack. The key novelty is the combination of a strain energy split with a partial rank-I relaxation in the vicinity of the diffuse interface. The former is necessary to account for physically meaningful crack kinematics like crack closure, the latter ensures the mechanical jump conditions throughout the diffuse region. The model is verified by a convergence study, where a circular bi-material disc with and without a crack is subjected to radial loads. For the uncracked case, analytical solutions are taken as reference. In a second step, the model is applied to crack propagation, where a meaningful influence on crack branching is observed, that underlines the necessity of a reasonable homogenization scheme. The presented model is particularly relevant for the combination of any variational strain energy split in the fracture phase-field model with a diffuse modeling approach for material heterogeneities.

On the Differences Between Practical and Cognitive Presumptions

The study of presumptions has intensified in argumentation theory over the last years. Although scholars put forward different accounts, they mostly agree that presumptions can be studied in deliberative and epistemic contexts, have distinct contextual functions (guiding decisions vs. acquiring information), and promote different kinds of goals (non-epistemic vs. epistemic). Accordingly, there are “practical” and “cognitive” presumptions. In this paper, I show that the differences between practical and cognitive presumptions go far beyond contextual considerations. The central aim is to explore Nicholas Rescher’s contention that both types of presumptions have a closely analogous pragmatic function, i.e., that practical and cognitive presumptions are made to avoid greater harm in circumstances of epistemic uncertainty. By comparing schemes of practical and cognitive reasoning, I show that Rescher’s contention requires qualifications. Moreover, not only do practical and cognitive presumptions have distinct pragmatic functions, but they also perform different dialogical functions (enabling progress vs. preventing regress) and, in some circumstances, cannot be defeated by the same kinds of evidence. Hence, I conclude that the two classes of presumptions merit distinct treatment in argumentation theory.