Planting in Metallized Reflective Mulch Did Not Significantly Benefit Development of New Hybrid Citrus Seedlings

The U.S. Department of Agriculture citrus scion breeding program is urgently working on developing huanglongbing (HLB; pathogen Candidatus Liberibacter asiaticus)-tolerant cultivars with excellent fruit quality and productivity when HLB-affected. The slow process of assessing new citrus hybrids is a major impediment to delivery of these much-needed cultivars. We generate thousands of hybrids each year, germinate the seedlings, grow them for 2 years in the greenhouse, plant them at high density in a field where the disease HLB is abundant, grow them for 5 to 10 years, and make selections based on tree performance and fruit quality of these HLB-affected trees. Based on promising reports of accelerated citrus growth when grown in a metallized reflective mulch (MRM) system, we tested the hypothesis that the MRM system may accelerate growth and selection of new hybrid seedlings compared with conventional soil culture (CSC). In the MRM system, tree rows are covered with a layer of metallized plastic film and drip irrigation is installed beneath the plastic. In 2 years of analysis, tree canopy volume was significantly greater with MRM in 2020 (27% greater than CSC) but not in 2021, and MRM tree height was greater in 2021 (7% greater than CSC). Mortality was significantly greater with MRM in both 2020 and 2021(in 2021: 32% vs. 17% under CSC), and MRM trees had more chlorotic leaves. Because of staff limitations, plant debris and soil were not routinely cleared from MRM, thus diminishing any benefit from the reflective surface. Better maintenance might have resulted in more sustained evidence of MRM growth benefits. With the current resource availability, the MRM system does not appear to accelerate the assessment of hybrid seedling trees.

Application of Green Design and Manufacturing in Mechanical Engineering: Education, Scientific Research, and Practice

Green design and manufacturing strategies are necessary to cope with the current resource, energy, and environmental problems of the manufacturing industry. To meet various enterprises’ needs for green design and manufacturing, colleges and universities should integrate these concepts into their curricula. This study discusses the application of green strategies in the mechanical engineering field from the viewpoints of teaching, scientific research, and practical education. Based on its development and a basic connotation analysis, this study highlights the challenges and urgency of incorporating green concepts into teaching and research modules of mechanical engineering, as well as methods and implementation strategies to incorporate them in professional curricula using teaching method reform and the teaching and research integration method. An experimental training course of advanced manufacturing processes at the authors’ institution was amended to emphasize the integrated application of green design and manufacturing. This integration not only enriches the field of mechanical engineering but also provides scientific research directions and methods to educators, along with new ideas to imbibe students with mechanical talents for their technical development. These efforts lay the foundation for the sustainable development of China’s manufacturing industry.

Measuring the Differences of Public Health Service Facilities and Their Influencing Factors

The equitable distribution of public health facilities is a major concern of urban planners. Previous studies have explored the balance and fairness of various medical resource distributions using the accessibility of in-demand public medical service facilities while ignoring the differences in the supply of public medical service facilities. First aid data with location information and patient preference information can reflect the ability of each hospital and the health inequities in cities. Determining which factors affect the measured differences in public medical service facilities and how to alter these factors will help researchers formulate targeted policies to solve the current resource-balance situation of the Ministry of Public Health. In this study, we propose a method to measure the differences in influence among hospitals based on actual medical behavior and use geographically weighted regression (GWR) to analyze the spatial correlations among the location, medical equipment, medical ability, and influencing factors of each hospital. The results show that Wuhan presents obvious health inequality, with the high-grade hospitals having spatial agglomeration in the city-center area, while the number and quality of hospitals in the peripheral areas are lower than those in the central area; thus, the hospitals in these peripheral areas need to be further improved. The method used in this study can measure differences in the influence of public medical service facilities, and the results are consistent with the measured differences at hospital level. Hospital influence is not only related to the equipment and medical ability of each hospital but is also affected by location factors. This method illustrates the necessity of conducting more empirical research on the public medical service supply to provide a scientific basis for formulating targeted policies from a new perspective.

Is bribing a good strategy? Imbalanced interdependence and hazard of opportunism in bribery

PurposeIn fragile institutional environments, firms often have no choice but bribery as the means to access the services monopolized by the government. Corrupt government officials whose resources are valuable to many different firms can easily find other firms willing to offer bribes. The purpose of this paper is to examine whether and how this imbalanced interdependence exposes the bribing firm to the hazard of opportunism from the bribed officials.Design/methodology/approachThis study draws on World Business Environment Survey (WBES) data and the instrumental variable (IV) Probit estimator with Heckman correction for the potential selection bias.FindingsThe authors find that the more firms depend on bribery to acquire governmental resources, the severer the level of opportunism they encounter from the government officials. In addition, the authors find that although the presence of a legal alternative to bribery reduces the level of a corrupt government official's opportunism that a bribing firm experiences, the more firms depend on bribery despite the presence of a legal alternative, the higher the level of the corrupt official's opportunism that the firm will experience. Finally, the authors find that establishing a relational contract with government officials reduces the hazard of opportunism.Originality/valueThe study contributes to the resource dependence literature by finding that a greater imbalance in the interdependence between two parties in bribery exposes the more dependent party to a larger hazard of opportunism. The finding that an ineffective alternative to a current resource provider would not strengthen but weaken a resource seeker's bargaining power expands the literature. The authors also contribute to the corruption research by showing the significant strategic, not legal, risk to bribing firms of engaging in bribery, which to date has not been sufficiently discussed.

Reliable Service Function Chain Deployment Method Based on Deep Reinforcement Learning

Network function virtualization (NFV) is a key technology to decouple hardware device and software function. Several virtual network functions (VNFs) combine into a function sequence in a certain order, that is defined as service function chain (SFC). A significant challenge is guaranteeing reliability. First, deployment server is selected to place VNF, then, backup server is determined to place the VNF as a backup which is running when deployment server is failed. Moreover, how to determine the accurate locations dynamically with machine learning is challenging. This paper focuses on resource requirements of SFC to measure its priority meanwhile calculates node priority by current resource capacity and node degree, then, a novel priority-awareness deep reinforcement learning (PA-DRL) algorithm is proposed to implement reliable SFC dynamically. PA-DRL determines the backup scheme of each VNF, then, the model jointly utilizes delay, load balancing of network as feedback factors to optimize the quality of service. In the experimental results, resource efficient utilization, survival rate, and load balancing of PA-DRL were improved by 36.7%, 35.1%, and 78.9% on average compared with benchmark algorithm respectively, average delay was reduced by 14.9%. Therefore, PA-DRL can effectively improve reliability and optimization targets compared with other benchmark methods.

Design and comparison of scheduling strategy for teleconsultation

BACKGROUND: Telemedicine is playing an increasingly more important role in disease diagnosis and treatment. The market of telemedicine application is continuously promoted, thus bringing some issues on telemedicine operations management. OBJECTIVE: We aimed to compare the teleconsultation scheduling performance of newly designed proactive strategy and existing static strategy and explore the decision-making under different conditions. METHODS: We developed a discrete-event simulation model based on practical investigation to describe the existing static scheduling strategy of teleconsultation. The static strategy model was verified by comparing it with the historical data. Then a new proactive strategy was proposed, whose average waiting time, variance of waiting time and completed numbers were compared with the static strategy. RESULTS: The analysis indicated that the proactive strategy performed better than static under the current resource allocation. Furthermore, we explored the impact on the system of both strategies varying arrival rate and experts’ shift time. CONCLUSIONS: Under different shift times and arrival rates, the managers of telemedicine center should select different strategy. The experts’ shift time had a significant impact on all system performance indicators. Therefore, if managers wanted to improve the system performance to a greater extent, they needed to reduce the shift time as much as possible.

Marine current energy assessment and the hydrodynamic design of the hydrokinetic turbine for the Moroccan Mediterranean Coast

Generating electricity through renewable energies is growing increasingly to reduce the huge demand on electricity and the impact of fossil energies on the environment, the most common sources forms used are: the wind, the sun, the photovoltaic and the thermal, without forgetting hydropower by the bays of dams. Fortunately, 70% of our planet is covered by the seas and oceans, this area constitutes a huge potential for electricity production to be exploited. The scientific advances of recent years allow a better exploitation of these resources especially the marine current due to its reliability and predictability. The marine current energy is extracted using a hydrokinetic turbine (HKT) which transform the kinetic energy of water into an electrical energy. The exploitation of this resource needs in the first step the assessment of marine currents in the study area for implementing the HKT, and the second step is designing an adequate technology. The main goal of this study is the assessment of the marine current resource on the Moroccan Mediterranean coast to evaluate the suitable area to implement the HKT, and to determine the marine current speed intensities at different depths. As well as, to estimate an average potential existing in the site. Moreover, we will conduct a study based on the results of the assessment that was made to design a horizontal axis marine current turbine (HAMCT). Two hydrofoil profile were considered to design a HAMCT using the Blade Element Theory (BEM) and calculating their performances adapted to the site conditions Naca4415 and s8052. In addition, a comparison was made between this two HAMCT hydrofoil profile for deciding the best one for implementing in the studied area.

A leader-followers game of emergency preparedness for aderse events

Natural disasters occur across the globe, resulting in billions of dollars of damage eachyear. Effective preparation before a disaster can help to minimize damages, economic impact, and lossof human life. This paper uses a game theory framework to set up a leader-followers model for resourcedistribution to several geographic zones before an adverse event. The researchers model populationmembers who may choose to prepare in advance of an event by acquiring supplies, whereas othersmay wait until the last minute. Failure to prepare in advance could result in a significant loss dueto the chance that supplies may no longer be available. Numerical simulations are run to determinehow the leader should distribute supplies to maximize the preparedness of the overall population. Itwas found that population size is a significant factor for supply distribution, but the behaviour ofindividuals within a zone is also important. Much of the current resource allocation research focuseson the logistics and economics of supply distribution, but this paper demonstrates that social aspectsshould also be considered.

Why do inequality and deprivation produce high crime and low trust?

Humans sometimes cooperate to mutual advantage, and sometimes exploit one another. In industrialised societies, the prevalence of exploitation, in the form of crime, is related to the distribution of economic resources: more unequal societies tend to have higher crime, as well as lower social trust. We created a model of cooperation and exploitation to explore why this should be. Distinctively, our model features a desperation threshold, a level of resources below which it is extremely damaging to fall. Agents do not belong to fixed types, but condition their behaviour on their current resource level and the behaviour in the population around them. We show that the optimal action for individuals who are close to the desperation threshold is to exploit others. This remains true even in the presence of severe and probable punishment for exploitation, since successful exploitation is the quickest route out of desperation, whereas being punished does not make already desperate states much worse. Simulated populations with a sufficiently unequal distribution of resources rapidly evolve an equilibrium of low trust and zero cooperation: desperate individuals try to exploit, and non-desperate individuals avoid interaction altogether. Making the distribution of resources more equal or increasing social mobility is generally effective in producing a high cooperation, high trust equilibrium; increasing punishment severity is not.