801 research outputs found
How to reduce cost and increase efficiency of shipping enterprises in developing service supply chain
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The Approach to Increase Incomes of Peasants in China at the Present Stage
Revive, Restore, Revitalize: An Eco-economic Methodology for Maasai Mara
The Maasai Mara in Kenya, renowned for its biodiversity, is witnessing
ecosystem degradation and species endangerment due to intensified human
activities. Addressing this, we introduce a dynamic system harmonizing
ecological and human priorities. Our agent-based model replicates the Maasai
Mara savanna ecosystem, incorporating 71 animal species, 10 human
classifications, and 2 natural resource types. The model employs the metabolic
rate-mass relationship for animal energy dynamics, logistic curves for animal
growth, individual interactions for food web simulation, and human intervention
impacts. Algorithms like fitness proportional selection and particle swarm
mimic organism preferences for resources. To guide preservation activities, we
formulated 21 management strategies encompassing tourism, transportation,
taxation, environmental conservation, research, diplomacy, and poaching,
employing a game-theoretic framework. Using the TOPSIS method, we prioritized
four key developmental indicators: environmental health, research advancement,
economic growth, and security. The interplay of 16 factors determines these
indicators, each influenced by our policies to varying degrees. By evaluating
the policies' repercussions, we aim to mitigate adverse animal-human
interactions and equitably address human concerns. We classified the policy
impacts into three categories: Environmental Preservation, Economic Prosperity,
and Holistic Development. By applying these policy groupings to our ecosystem
model, we tracked the effects on the intricate animal-human-resource dynamics.
Utilizing the entropy weight method, we assessed the efficacy of these policy
clusters over a decade, identifying the optimal blend emphasizing both
environmental conservation and economic progression.Comment: 25 pages, 16 figure
Research on the impact of asteroid mining on global equity
In the future situation, aiming to seek more resources, human beings decided
to march towards the mysterious and bright starry sky, which opened the era of
great interstellar exploration. According to the Outer Space Treaty, any
exploration of celestial bodies should be aimed at promoting global equality
and for the benefit of all nations. Firstly, we defined global equity and set a
Unified Equity Index (UEI) model to measure it. We merge the factors with
greater correlation, and finally, get 6 elements, and then use the entropy
method (TEM) to find the dispersion of these elements in different countries.
Then use principal component analysis (PCA) to reduce the dimensionality of the
dispersion, and then use the scandalized index to obtain the global equity.
Secondly, we simulated a future with asteroid mining and evaluated its impact
on Unified Equity Index (UEI). Then, we divided the mineable asteroids into
three classes with different mining difficulties and values, identified 28
mining entities including private companies, national and international
organizations. We considered changes in the asteroid classes, mining
capabilities and mining scales to determine the changes in the value of
minerals mined between 2025 and 2085. We convert mining output value into
mineral transaction value through allocation matrix. Based on grey relational
analysis (GRA). Finally, we presented three possible versions of the future of
asteroid mining by changing the conditions. We propose two sets of
corresponding policies for changes in future trends in global fairness with
asteroid mining. We test the separate and combined effects of these policies
and find that they are positive, strongly supporting the effectiveness of our
model.Comment: 19 page
Automatic Segmentation of Sinkholes Using a Convolutional Neural Network
Sinkholes are the most abundant surface features in karst areas worldwide. Understanding sinkhole occurrences and characteristics is critical for studying karst aquifers and mitigating sinkhole-related hazards. Most sinkholes appear on the land surface as depressions or cover collapses and are commonly mapped from elevation data, such as digital elevation models (DEMs). Existing methods for identifying sinkholes from DEMs often require two steps: locating surface depressions and separating sinkholes from non-sinkhole depressions. In this study, we explored deep learning to directly identify sinkholes from DEM data and aerial imagery. A key contribution of our study is an evaluation of various ways of integrating these two types of raster data. We used an image segmentation model, U-Net, to locate sinkholes. We trained separate U-Net models based on four input images of elevation data: a DEM image, a slope image, a DEM gradient image, and a DEM-shaded relief image. Three normalization techniques (Global, Gaussian, and Instance) were applied to improve the model performance. Model results suggest that deep learning is a viable method to identify sinkholes directly from the images of elevation data. In particular, DEM gradient data provided the best input for U-net image segmentation models to locate sinkholes. The model using the DEM gradient image with Gaussian normalization achieved the best performance with a sinkhole intersection-over-union (IoU) of 45.38% on the unseen test set. Aerial images, however, were not useful in training deep learning models for sinkholes as the models using an aerial image as input achieved sinkhole IoUs below 3%
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