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Factors Influencing the Acidification Trends in Agriculture Soils: A Case Study of Slovakia

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Journal of Geoscience and Environment Protection 2024年第9期12卷 269-282页

作者： Jarmila Makovníková Stanislav Kološta boris Pálka National Agricultural and Food Centre/Soil Science and Conservation Research Institute Bratislava Regional Station Banská Bystica Slovakia Faculty of Ecomonics Matej Bel University in Banská Bystrica Tajovského Banská Bystrica Slovakia

This study aims to evaluate the development of soil reaction values in 15 key localities of soil Partial Monitoring System from 1994 to 2023, and to identify the most important regional drivers of pH value development. Soil samples were collected from the depth 0 - 0.10 m yearly in the spring (5 samples from each locality). In the dry soil, samples were determined actively and exchanged soil reaction. The most significant negative changes (decreases of soil reaction) were determined in Haplic Stagnosols group and Cambisols group. The pH value in topsoil is primarily controlled by soil type and soil substrate, soil management and land use, and to a lesser extent by climatic region.

关键词： pH Value Acidification Climatic Region Soil Type

What If the Protection against Oxidation of Chromia-Forming Alloys Was Not Always Due to the Chromia Layer?

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American Journal of Analytical Chemistry 2024年第9期15卷 286-302页

作者： boris Contri Stéphane Valette Marina Soustre Pierre Lefort IRCER European Ceramics Centre UMR CNRS 7315 University of Limoges 12 rue Atlantis Limoges Cedex France

Chromia-forming alloys have good resistance to oxidizing agents such as O2, CO2, … It is accepted that the protection of these alloys is always due to the chromia layer formed at the surface of the alloys, which acts as a barrier between the oxidizing gases and the alloy substrates, forming a diffusion zone that limits the overall reaction rate and leads to parabolic kinetics. But this was not verified in the study devoted to Inconel®625 the oxidation in CO2 that was followed by TGA, with characterizations by XRD, EDS and FIB microscopy. Contrary to what was expected and accepted in similar studies on other chromia-forming alloys, it was shown that the diffusion step that governs the overall reaction rate is not located inside the chromia layer but inside the alloy, precisely inside a zone just beneath the interface alloy/chromia, this zone being depleted in chromium. The chromia layer, therefore, plays no kinetic role and does not directly protect the underlying alloy. This result was demonstrated using a simple test that consisted in removing the chromia layer from the surface of samples partially oxidized and then to continue the thermal treatment: insofar as the kinetics continued without any change in rate, this proved that this surface layer of oxide did not protect the substrate. Based on previous work on many chromia-forming alloys, the possibility of a similar reaction mechanism is discussed. If the chromia layer is not the source of protection for a number of chromia-forming alloys, as is suspected, this might have major consequences in terms of industrial applications.

关键词： Chromia-Forming Alloys Chromia Layer Oxidation Protection Inconel®625 Kinetics

Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia

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Journal of Geoscience and Environment Protection 2024年第6期12卷 135-150页

作者： Jarmila Makovníková Stanislav Kološta boris Pálka National Agricultural and Food Centre Soil Science and Conservation Research Institute Bratislava Regional Station Bansk Bystica Bansk Bystrica Slovakia Faculty of Economics Matej Bel University Bansk Bystrica Slovakia

This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants).

关键词： Agroecosystem Services Climatic Zone Mapping Trade-Offs Synergies

Learning the continuous-time optimal decision law from discrete-time rewards

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National Science Open 2024年第5期3卷 130-147页

作者： Ci Chen Lihua Xie Kan Xie Frank leroy Lewis Yilu Liu Shengli Xie School of Automation Guangdong University of TechnologyGuangdong Key Laboratory of IoT Information Technology Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of Education School of Electrical and Electronic Engineering Nanyang Technological University 111 Center for Intelligent Batch Manufacturing Based on IoT Technology UTA Research Institute the University of Texas at Arlington Department of Electrical Engineering and Computer Science University of Tennessee Oak Ridge National Laboratory Guangdong-HongKong-Macao Joint Laboratory for Smart Discrete Manufacturing

The concept of reward is fundamental in reinforcement learning with a wide range of applications in natural and social sciences. Seeking an interpretable reward for decision-making that largely shapes the system's behavior has always been a challenge in reinforcement learning. In this work, we explore a discrete-time reward for reinforcement learning in continuous time and action spaces that represent many phenomena captured by applying physical laws. We find that the discrete-time reward leads to the extraction of the unique continuous-time decision law and improved computational efficiency by dropping the integrator operator that appears in classical results with integral rewards. We apply this finding to solve output-feedback design problems in power systems. The results reveal that our approach removes an intermediate stage of identifying dynamical models. Our work suggests that the discrete-time reward is efficient in search of the desired decision law, which provides a computational tool to understand and modify the behavior of large-scale engineering systems using the optimal learned decision.

关键词： continuous-time state and action decision law learning discrete-time reward dynamical systems reinforcement learning

Modelling of a WDM Network Using Graph Theory and Dijkstra Algorithm for Traffic Redirection

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Journal of Computer and Communications 2024年第7期12卷 78-93页

作者： Eric Michel Deussom Djomadji Ebude Carine Awasume Eloundou boris Donald Department of Electrical and Electronic Engineering College of Technology University of Buea Buea Cameroon Division of ICT National Advanced School of Post Telecommunication and ICT University of Yaounde I Yaounde Cameroon

Optical transport networks are now the basic infrastructure of modern communications systems, including the SDH and WDM backbone network of local network operators, in the case of Cameroon. Given the colossal investments required to deploy these networks, particularly related to the cost of equipment (optical fibers, transponders and multiplexers), the optimization of bandwidth and dynamic allocation of resources is essential to control operating costs and ensure continuity of service. Automatic switching technology for optical networks brings intelligence to the control plane to fully facilitate bandwidth utilization, traffic redirection, and automatic configuration of end-to-end services. This paper considers a local network operator’s WDM network without the implementation of the automatic switching technology, develops a network modeling software platform called Graphic Networks and using graph theory integrates a particularity of the automatic switching technology, which is the automatic rerouting of traffic in case of incident in the network. The incidents considered here are those links or route failures and node failures.

关键词： Graph Theory Backbone Network WDM Djikstra Algorithm

Evaluation of Four Anthropogenic Activity Impacts on Heavy Metal Quality of the Kumba River in the South West Region of Cameroon

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Journal of Water Resource and Protection 2024年第5期16卷 361-380页

作者： Martin Keghe Nkobe Barthelemy Ndongo Kanouo boris Merlain Djousse Salomon Nyasse Institute of Agricultural Research for Development (IRAD) Yaound&#233 Cameroon Faculty of Agronomy and Agricultural Sciences (FASA) University of Dschang Dschang Cameroon

Anthropogenic activities have contributed to pollution of water bodies through deposition of diverse pollutants amongst which are heavy metals. These pollutants, which at times are above the maximum concentration levels recommended, are detrimental to the quality of the water, soil and crops (plant) with subsequent human health risks. The objective of the work was to evaluate the impacts of human-based activities on the heavy metal properties of surface water with focus on the Kumba River basin. Field observations, interviews, field measurements and laboratory analyses of different water samples enabled us to collect the different data. The results show four main human-based activities within the river basin (agriculture, livestock production, domestic waste disposal and carwash activities) that pollute surface water. Approximately 20.61 tons of nitrogen and phosphorus from agricultural activities, 156.48 tons of animal wastes, 2517.5 tons of domestic wastes and 1.52 tons of detergent from carwash activities were deposited into the river each year. A highly significant difference at 1% was observed between the upstream and downstream heavy metal loads in four of the five heavy metals tested except for copper that was not significant. Lead concentrations were highest in all the activities with an average of 2.4 mg∙L−1 representing 57.81%, followed by zinc with 1.596 mg∙L−1 (38.45%) and manganese with 0.155 mg∙L−1 (3.74%) for the different anthropogenic activities thus indicating that these activities highly lead to pollution of the Kumba River water. The level of zinc and manganese was significantly influenced at ρ 005 by anthropogenic activities though generally the variations were in the order: carwash (3.196 mg∙L−1) −1) −1) −1) r

关键词： Metal Properties Human-Based Activities Kumba River Basin Surface Water

Artificial light at night(ALAN) pollution alters bat lunar chronobiology:insights from broad-scale long-term acoustic monitoring

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Ecological Processes 2024年第01期13卷 176-187页

作者： Han Li Pauline Allen Saige boris Samantha Lagrama Jade Lyons Christina Mills Pauline Moussi Casey Nichols Carter Tacosik Mc Kenzie Tsaousis Nyzaya Livingston Wilson John F.Grider Kevin A.Parker Matina C.Kalcounis-Rueppell Department of Biology University of Nebraska Omaha Department of Biology University of North Carolina Greensboro Colorado Parks and Wild-life Parker Ecology LLC Department of Biological Sciences University of Alberta

Background The timing of behavior and habitat use of nocturnal animals can be influenced by the lunar cycle in nature. The prevalence of artificial light at night(ALAN) has been recognized as a source of environmental pol-lution. The interaction between ALAN and the lunar cycle on bat behavior is important for understanding anthro-pogenic effects on bats. We utilized a decade(2012–2022) of acoustic monitoring data collected in North Carolina, United States, to investigate the relationship between bat activity, lunar cycle, and light pollution. We examined whether the amount of lunar illumination affected species-specific nightly activity and whether hourly bat activity patterns varied between nights with different moon phases. We further investigated if the relationship between bat activity and the lunar cycle might be altered by light *** We found that seven bat species showed activity variation across nights in relation to the amount of moon illumination when ALAN was absent. In general, bats were less active on full moon nights compared to new moon nights. Light pollution interacted with the bat–lunar relationship in five of the seven species, masking the effect of the lunar cycle. We identified delayed bat activity patterns on nights with a full or waxing moon in seven species, and light pollution altered that pattern in four species. Overall, ALAN was associated with decreased bat activity inde-pendent of lunar cycle *** Our study demonstrated that at a broad spatial scale, ALAN negatively affected many North American temperate bat species and altered their lunar chronobiology. As light pollution is spreading to historically dark areas and habitats, ALAN might couple with other threats, such as the white-nose syndrome or climate change, to cause cascading damage in the environment that depends on ecosystem services such as pest control provided by bats. We argue that further research and conservation actions are needed to mitigate

关键词： Artificial light at night ALAN Bats Chiroptera Chronobiology Light pollution Lunar cycle Moonlight

On the “Onion Husk” Algorithm for Approximate Solution of the Traveling Salesman Problem

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1557-1570页

作者： Mikhail E. Abramyan Nikolai I. Krainiukov boris F. Melnikov Faculty of Computational Mathematics and Cybernetics Shenzhen MSU-BIT University Shenzhen China Department of Algebra and Discrete Mathematics Southern Federal University Rostov-on-Don Russian Federation

The paper describes some implementation aspects of an algorithm for approximate solution of the traveling salesman problem based on the construction of convex closed contours on the initial set of points (“cities”) and their subsequent combination into a closed path (the so-called contour algorithm or “onion husk” algorithm). A number of heuristics related to the different stages of the algorithm are considered, and various variants of the algorithm based on these heuristics are analyzed. Sets of randomly generated points of different sizes (from 4 to 90 and from 500 to 10,000) were used to test the algorithms. The numerical results obtained are compared with the results of two well-known combinatorial optimization algorithms, namely the algorithm based on the branch and bound method and the simulated annealing algorithm. .

关键词： Branch and Bound Method Contour Algorithm “Onion Husk” Algorithm Simulated Annealing Method Traveling Salesman Problem

On Some Properties of Graph of Prefix Code

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1571-1581页

作者： Nikolai I. Krainiukov Mikhail E. Abramyan boris F. Melnikov Faculty of Computational Mathematics and Cybernetics Shenzhen MSU-BIT University Shenzhen China Department of Algebra and Discrete Mathematics Southern Federal University Rostov-on-Don Russian Federation

We investigate decomposition of codes and finite languages. A prime decomposition is a decomposition of a code or languages into a concatenation of nontrivial prime codes or languages. A code is prime if it cannot be decomposed into at least two nontrivial codes as the same for the languages. In the paper, a linear time algorithm is designed, which finds the prime decomposition. If codes or finite languages are presented as given by its minimal deterministic automaton, then from the point of view of abstract algebra and graph theory, this automaton has special properties. The study was conducted using system for computational Discrete Algebra GAP. .

关键词： Finite Languages Minimal Deterministic Automata Concatenation Codes Graph of Automaton Free Algebra