Multi-UAV Optimal Mission Assignment and Path Planning for Disaster Rescue Using Adaptive Genetic Algorithm and Improved Artificial Bee Colony Method

An optimal mission assignment and path planning method of multiple unmanned aerial vehicles (UAVs) for disaster rescue is proposed. In this application, the UAVs include the drug delivery UAV, image collection UAV, and communication relay UAV. When implementing the modeling and simulation, first, three threat sources are built: the weather threat source, transmission tower threat source, and upland threat source. Second, a cost-revenue function is constructed. The flight distance, oil consumption, function descriptions of UAV, and threat source factors above are considered. The analytic hierarchy process (AHP) method is utilized to estimate the weights of cost-revenue function. Third, an adaptive genetic algorithm (AGA) is designed to solve the mission allocation task. A fitness function which considers the current and maximum iteration numbers is proposed to improve the AGA convergence performance. Finally, an optimal path plan between the neighboring mission points is computed by an improved artificial bee colony (IABC) method. A balanced searching strategy is developed to modify the IABC computational effect. Extensive simulation experiments have shown the effectiveness of our method.

How COVID-19 Affects Agricultural Food Sales: Based on the Perspective of China’s Agricultural Listed Companies’ Financial Statements

Agricultural food is generally regarded as the basis of “national security” by most countries. Through marketing strategies, promoting the sales of agri-food products in the context of a pandemic is of great significance to national food security and economic growth. The purpose of our study is to understand how the COVID-19 crisis affects the sales of agri-food products as well as the organizational and management changes it brings. By understanding those points above, we can address the problem and policy challenges to better promote the recovery of the agri-food sector from the effects caused by COVID-19. The demand is today overwhelmingly urgent. Based on the data of China’s agricultural-listed companies from 2015 to 2020, this study adopted the perspective of financial statements and conducted empirical analysis through the translog revenue function, and the results showed that the COVID-19 pandemic has reduced the sales of agri-food products, and the sales of agri-food products by large agricultural companies have fallen more than those of small- and medium-sized ones. Based on the results of the study, the government can consider the policy of providing financial support and temporary subsidies to agri-food enterprises during the pandemic, while agri-food enterprises actively practice digital marketing to reduce the adverse impact of COVID-19 on agri-food sales.

The Impact of COVID-19 on the Revenue of the Livestock Industry: A Case Study of China

The COVID-19 pandemic has affected social order and people’s health and has also caused a heavy blow to the livestock industry, affecting animal management and welfare. The livestock industry is one of the main contributors to economic growth in many regions, and it is of great significance to people’s lives and regional economic growth. COVID-19 has reduced the livestock industry’s market as well as consumers’ opportunities to purchase livestock products, resulting in no sales or low sales of livestock or their products. The main purpose of this study is to consider the impact of the pandemic on the revenue of the livestock industry, and to study the challenges arising from the pandemic to the livestock industry. Based on the perspective of financial statements, we estimate the impact of COVID-19 through the translog revenue function of listed Chinese livestock companies from 2015 to 2020, and the study results show that the COVID-19 pandemic has reduced the revenue of the livestock industry, but the decline in revenue of large livestock enterprises is lower than that of small and medium-sized livestock enterprises. In the last two parts of this study, we make policy recommendations to livestock enterprises and the authorities.

The Impact of the COVID-19 Pandemic on Consumers’ Preferences for Wood Furniture: An Accounting Perspective

The COVID-19 pandemic has had a major impact on forest product markets and the forest product industry, and has also seriously affected the sales of forest products. This research aimed to analyze people’s preference for wood furniture and make policy recommendations. We examined the impact of the pandemic on consumers’ preferences for wood furniture from the perspective of accounting. Taking the accounting data of wood furniture enterprises as the research object, through the translog revenue function, and using the relationship between revenue and consumption in economics, we found that the COVID-19 pandemic has reduced consumers’ preferences for wood furniture, but the decline in preference is smaller for wood furniture produced by extra-large furniture manufacturers. This study contributes to the literature and in view of our research results and the severity of the COVID-19 pandemic, we provide policy suggestions for the related governmental agencies and wood furniture manufacturers, in this special environment, that can reduce the negative impact of a pandemic on the wood furniture industry.

The Impact of the National Nutrition Program 2017–2030 on People’s Food Purchases: A Revenue-Based Perspective

The General Office of the State Council of China promulgated the National Nutrition Program 2017–2030 in 2017 to guide the people to improve their food supply and nutritional intake. This study uses qualitative and quantitative information which are analyzed to estimate the change in people’s food purchases following the implementation of the National Nutrition Program 2017–2030, and puts forward measures that should be taken by the competent authorities and stakeholders. We use the translog revenue function of the food industry, and based on the data of listed companies of Chinese food enterprises from 2015 to 2020, and this study find that the National Nutrition Program 2017–2030 has had a positive impact on people’s food purchases, and the impact is more obvious in people’s food purchases from large food manufacturers. Finally, we also provide regulators with public policy implications, and provide food manufacturers with development suggestions.

Target Search Algorithm for AUV Based on Real-Time Perception Maps in Unknown Environment

For the problem of AUV target searches in unknown underwater environments, a target search algorithm for AUVs based on a real-time perception map is proposed. Real-time perception maps, including target existence probability maps, uncertainty maps, and pheromone maps and their updating rules, are established. Attraction source maps and search status maps based on the environmental information detected by the AUV are established. The maps are used for the AUV to search for corner areas that are unknown to a high degree and areas with low coverage around the current location. At the same time, a release mechanism for attraction and revisiting pheromones is established by combining a neural excitation network algorithm to make the gradient spread in the pheromone grid map. By setting up a search revenue function based on real-time perception maps, an AUV search decision-making method is established. When the AUV finds a suspected target, the AUV approaches the suspected target. The path planning of the AUV is carried out through an improved artificial potential field method. The short-distance confirmation of the target and obstacle avoidance in the search process are realized. The simulation results show that the algorithm has high search efficiency. Additionally, when the target exists in a corner area, the probability of the AUV to quickly search for the target is fast and feasible.

Macro and Micro Dynamics of Productivity: From Devilish Details to Insights

Firm-level, revenue-based productivity measures are ubiquitous in studies of firm dynamics and aggregate outcomes. One common measure is increasingly interpreted as reflecting “distortions” since in distortions’ absence, equalization of marginal revenue products should yield no dispersion in this measure. Another common but distinct measure is the residual of the firm-level revenue function, which reflects “fundamentals.” Using micro-level US manufacturing data, we find these alternative measures are highly correlated, exhibit similar dispersion, and have similar relationships with growth and survival. However, the distinction between these alternative measures is critically important for quantitative assessment of the level and decline of allocative efficiency. (JEL D21, D22, D24, G32, L60)

Maintenance Optimization Based on Three-Stage Failure Process under Performance-Based Contracting

As a new form of support contract, performance-based contracting has been extensively applied in both public and private sectors. However, maintenance policies under performance-based contracting have not gotten enough attention. In this paper, a preventive maintenance optimization model based on three-stage failure process for a single-component system is investigated with an objective of maximizing the profit and improving system performance at a lower cost under performance-based contracting. Different from conventional optimization models, the step revenue function is used to correlate profit with availability and cost. Then, a maintenance optimization model is proposed to maximize profit by optimizing the inspection interval. Moreover, the customers’ upper limit of funds is considered when we use the revenue function, which has rarely been considered in past studies. Finally, a case study on the cold water pumps along with comparison of linear and step revenue function and sensitivity analysis is provided to illustrate the applicability and effectiveness of our proposed approach.

An Optimal Compensation Agency Model for Sustainability under the Risk Aversion Utility Perspective

This paper explores how to construct a fair and optimal compensation system between the principal and the agent in the face of financial compensation agency problems during a limited period in relation to the concept of sustainability. In the construction of the principal’s compensation system, the agent’s degree of operational financial effort will affect the overall revenue function for reaching sustainability. Both the principal and the agent have a maximum expected utility in the negative exponential pattern of the general hyperbolic absolute risk aversion (HARA) utility function that satisfies their respective objective functions. The proposed model and numerical example analysis results prove that the compensation system for sustainability can provide a fair and optimal financial system, from a sustainability perspective. The main contribution of this study is the construction and development of an optimal compensation agency model for risk management, which is derived by considering the effect of risk aversion utility on revenue. The proposed model can provide a fair and feasible approach within the issue of compensation, from the viewpoint of sustainability, for an optimal compensation agency problem.

The Impact of the Amendment of Taiwan’s Certified Public Accountant Act in 2007 on Large Accounting Firms

Taiwan’s Financial Supervisory Commission of the Executive Yuan promulgated the fully amended Certified Public Accountant Act in 2007, which directly led to significant changes in accounting law. From the perspective of the economic theory of law, this study investigates the amendment of the Certified Public Accountant Act resulting in an increase or decrease in the overall revenue and different revenue shares of accounting firms, and puts forward measures that should be taken by accounting firms and stakeholders. We focus on large accounting firms and divide the sample period into before and after 2008. This study uses the translog revenue function and revenue share functions of the public accounting industry, and based on the 1989–2017 Survey Report of Audit Firms in Taiwan, and we find that the amendment of the Certified Public Accountant Act has had a positive effect on overall revenue, increasing overall revenue and the overall management advisory services shares, and in reducing the overall accounting and auditing shares and tax services shares of large accounting firms. Additional analyses provide regulators with public policy implications and provide accounting firms with managerial information.