Set Of Indices Research Articles

Domino: A new framework for the automated identification of weather event precursors, demonstrated for European extreme rainfall

AbstractA number of studies have investigated the large‐scale drivers and upstream precursors of extreme weather events, making it clear that the earliest warning signs of extreme events can be remote from the impacted region in both time and space. Integrating and leveraging our understanding of dynamical precursors provides a new perspective on ensemble forecasting for extreme events, focused on building storylines of possible event evolution. This then acts as a tool for raising awareness of the conditions conducive to high‐impact weather and providing early warning of their possible development. However, operational applications of this developing knowledge base are limited, perhaps for want of a clear framework for doing so. Here, we present such a framework, supported by open software tools, designed for identifying large‐scale precursors of categorical weather events in an automated fashion and reducing them to scalar indices suitable for statistical prediction, forecast interpretation, and model validation. We demonstrate this framework by systematically analysing the precursor circulations of daily rainfall extremes across 18 regional‐ to national‐scale European domains. We discuss the precursor rainfall dynamics for three disparate regions, and show our findings are consistent with, and extend, previous work. We provide an estimate of the predictive utility of these precursors across Europe based on logistic regression, and show that large‐scale precursors can usefully predict heavy rainfall between two and six days ahead, depending on region and season. We further show how, for more continental‐scale applications, the regionally specific precursors can be synthesised into a minimal set of indices that drive heavy precipitation. We then provide comments and guidance for generalisation and application of our demonstrated approach to new variables, timescales, and regions.

Characterization of the recent (2019–2022) La Plata Basin hydrological drought from a centennial-scale perspective

Several major rivers within the La Plata Basin (LPB), the third largest basin in the world, have experienced record-low water levels between 2019 and 2022, with significant impacts for the economy of the region. This hydrological drought originated from a precipitation deficit over the headwaters of the Paraná, Paraguay, and Uruguay rivers, in response to an unusual multi-year La Niña episode. The objective of this study is to characterize the hydrological drought and quantify its unusualness by analyzing a set of indices based on daily, monthly, and annual streamflow and water levels of the main rivers of LPB, using centennial records. The results indicate that the recent hydrological drought was unprecedented in the context of the past 50 years in terms of severity and duration, featuring extreme drought conditions and duration over 25 months. The atmospheric drivers of the drought are analyzed, and future perspectives for water management are discussed.

On unconditionality of fractional Rademacher chaos in symmetric spaces

We study density estimates of an index set $\mathcal{A}$ under which the unconditionality (or even the weaker property of random unconditional divergence) of the corresponding Rademacher fractional chaos $\{r_{j_1}(t) \cdot r_{j_2}(t) \cdots r_{j_d}(t)\}_{(j_1,j_2,…,j_d) \in \mathcal{A}}$ in a symmetric space $X$ implies its equivalence in $X$ to the canonical basis in $\ell_2$. In the special case of Orlicz spaces $L_M$, unconditionality of this system is also shown to be equivalent to the fact that a certain exponential Orlicz space embeds into $L_M$.

Burning, edge burning & chromatic burning classification of some graph family

Graph ‘G’ is a Simple and undirected graph, which has a lowest number of color that is required to color the edge is called chromatic index. It is denoted by the symbol χ1(G). In order to burn a graph, a minimum source of edges is required which is called edge burning index or edge burning number and it is denoted by the symbol b1(G). A minimum cardinality of color graph set and the source of the burning index set are called edge chromatic burning and let us assume that it is represented by the symbol χb1(G). In this paper we are mainly concentrating on identifying the chromatic burning and edge chromatic burning graphs and their chromatic burning index using a specific graph family. They are Petersen graph, Helm graph and n- Sunlet graph.

Symbolic dynamics for active sets of a class of constrained nonlinear optimal control and MPC problems

Solutions to optimal control problems are usually understood to provide optimal trajectories. In this paper, we show that the optimal state-space system dynamics induce a dynamics of the active sets. More specifically, given the optimal active set at the solution obtained at the current time, its successor optimal active set (which, in turn, defines the successor solution) can be found with index set operations. These operations do not involve any optimal control (or other optimization or integration) problem, but they can be described with simple rules. These rules constitute the symbolic dynamics for active sets. The present paper treats a particular constrained nonlinear problem class, extending earlier results for the constrained linear-quadratic case.

An integrated accounting system of the economic-social-ecological framework for assessing the value of intensive land use: A case study of the Taihu Lake governance project

Assessing the value of land resources is a prerequisite for resource management, as well as for resolving the conflict between supply and demand. In the realm of intensive land use (ILU), a standardized framework for accounting methods from a project perspective has yet to be established. Therefore, taking the Taihu Lake governance project (TLGP) (which includes the Xingou River project, Xinmeng River project and Zoumatang River project) as a case study, this paper firstly constructs an integrated value accounting system based on economic, social and ecological frameworks. Furthermore, with consideration of physical parameters, we incorporated the integrated land section price method, income reduction method, alternative market method, and equivalent factor method are all incorporated to assess the value of ILU at distinct stages within the research area. This approach serves to elucidate the evolving dynamics of ILU valuation. The results showed that: (1) There were significant differences in the values generated by the ILU in different projects. The integrated value of the TLGP brought about by ILU was 177,189,300 yuan, and the ILU of the Xinmeng River project was significantly higher than the Zoumatang River project and the Xingou River project. (2) The ILU at different stages basically displayed the law of diminishing marginal utility. Consistent with changes in the different stages of the TLGP, the value of ILU in Stage I of the Zoumatang River project and the Xingou River project was significantly higher than that in Stage II. Additionally, the accounting system proposed in this study has the advantages of reasonable index setting and simple process operability. This helps to realize the comparison of ILU values across projects and stages. The results of this study can provide a reference for the management and sustainable use of land resources during the construction of water conservancy and other projects.

Criteria for Implementation of Circular Economy: Experiences from China and Implications for Vietnam

The global trend towards the development of a circular economy (CE) is of great significance, including for Vietnam. In recent years, Vietnam has made efforts to establish and improve its legal and policy framework related to CE. This research study aims to examine the evaluation criteria used for assessing CE development in China, a country that has achieved remarkable progress in this area. The findings of this study can provide valuable insights and serve as a crucial reference for Vietnam as it strives to formulate an evaluation criteria set for the effective implementation of the CE policies in the future. Building upon the experiences and lessons learned from the implementation of evaluation and monitoring criteria in China, this study also offers several recommendations for Vietnam's forthcoming implementation efforts. These recommendations encompass the development of comprehensive guidelines for data collection and computation of the evaluation index set, along with the establishment of transparent monitoring and auditing mechanisms for locally sourced data. Furthermore, fostering collaboration among relevant government agencies in data collection and consolidation is crucial. Specific communication strategies and reporting mechanisms tailored to local contexts should be devised, and nationally standardized reference values for evaluation criteria need to be established. Additionally, there is a need to design an evaluation criteria set specifically for the implementation of circular economy practices at the industrial park and enterprise levels in Vietnam.
 Keywords: Evaluation criteria, circular economy, China.

Changes in thermal niche position and breadth of bird assemblages in Spain in relation to increasing temperatures

AbstractAimAnimal communities around the world are responding to climate change by altering their taxonomic composition, mainly through an increase in the colonisation rate of warm‐dwelling species and the local extinction of cold‐dwelling ones. We assessed whether the taxonomic composition of bird assemblages in peninsular Spain has changed in accordance with the recent increase in temperature. We also evaluated the role of species thermal affinities and population dynamics on these changes.LocationPeninsular Spain.TaxonBirds.MethodsWe compared assemblages reported in the last Spanish breeding bird atlases (1998–2002 vs. 2014–2018) in 10 × 10 km squares. We described species' thermal niches by overlaying global species breeding distributions and world temperature metrics (based on mean, minimum, maximum and range), and then aggregated them to obtain a set of community thermal indices for each assemblage (CTIs and CTR for ranges). Long‐term average temperatures and local current temperatures were related to changes in CTIs using spatial GLMMs, which considered habitat change. We identified the species most responsible for variation in assemblages and regressed species' influence on thermal affinities and population dynamics.ResultsCTIs increased with temperature and warm‐dwelling species became more prevalent to the detriment of cold‐dwelling ones. However, we found a counteracting effect of temperature and habitat. Cold‐dwelling forest species were among the most influential species, mainly through colonisation, while warm‐dwelling farmland species contributed through local extinctions (both attenuated local increases in CTI). The mean thermal breadth of assemblages (CTR) decreased with temperatures.Main conclusionsThe taxonomic composition of bird assemblages shifted in line with the main expectations due to global change (thermophilisation), mainly due to local colonisation of warm‐dwelling species, although it did not show the pattern of thermal homogenisation suggested elsewhere. Our results add further evidence of the interplay between climate warming and land‐use change in the ongoing adjustment of animal communities.

Active moss biomonitoring of airborne potentially toxic elements in recreational areas of Moscow.

Active biomonitoring using the moss bag technique was applied to examine the atmospheric deposition of potentially toxic and other elements in recreational areas of Moscow. Moss bags with Sphagnum girgensohnii were placed in the territory of seven parks (Losiny Ostrov, Victory Park, Ostankino, Sokolniki, Izmailovo, Kuzminki-Lyublino, Tsaritsyno) at three locations in each park from June to September 2018. The content of 32 chemical elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Mn, Fe, Co, Zn, As, Br, Rb, Sr, Mo, Sb, Cs, Ba, La, Sm, Tb, Hf, Ta, W, Au, Th, U, Cu, Pb, and Cd in moss samples was determined by instrumental neutron activation analysis and atomic absorption spectrometry. After a 3-month exposure period, high uptake of Sb, U, Th, Sm, La, Mo, Zn, Co, Fe, V, Sc, etc. was observed in some of the moss samples. The physiologically active elements Cl and K and alkaline elements Rb and Cs were depleted from the moss tissue during the exposure. The high accumulation of Zn, Pb, Cu, Co, V, and Sb in moss samples evidenced an anthropogenic impact on the parks, mainly associated with road traffic. To determine the level of pollution, a set of environmental indices was calculated: contamination factor (CF), enrichment factor (EF), total pollution index (TPI), and relative accumulation factor (RAF). The highest RAF values were obtained for Sb on the territory of all parks. According to EF, the samples were enriched in Al, Fe, U, Pb, Cd, Au, Sb, Th, and Ta. High CF values were obtained for sites in Losiny Ostrov, Izmailovo, Tsaritsyno, and Kuzminki-Lyublino located close to roads. According to TPI, the level of air pollution on the territory of the abovementioned parks varied from moderate to high. To identify the major sources of pollution, correlation analysis and principal component analysis were applied.

The Full m Index Sets of P2×Pn

Shiu and Kwong (2008) studied the full friendly index set of P2×Pn, which only addressed the cases where m=0 or 1. In this paper, we significantly extend their work by determining the full m index set MP2×Pn for all values of m. Our key approach is to utilize graph embedding and recursion methods to deduce MP2×Pn for general m. In particular, we embed small graphs like C4 and K2 into P2×Pn and apply recursive techniques to prove the main results. This work expands the scope of previous graph labeling studies and provides new insights into determining the full m index set of product graphs. Given the broad range of applications for labeled graphs, this research can potentially impact fields like coding theory, communication network design, and more.

Does energy consumption play a key role? Re-evaluating the energy consumption-economic growth nexus from GDP growth rates forecasting

Given the strong link between economic growth and energy consumption, we construct a new set of energy consumption indices (ECI) to forecast GDP growth rates. The findings demonstrate the strong predictive power of the new indices. In particular, the electricity consumption index from the industrial sector has an excellent predictive performance and deserves the attention of the government and academia to help formulate economic growth targets. The mixed-frequency model with the Least Absolute Shrinkage and Selection Operator approach (MIDAS-LASSO) enables the full exploitation of energy consumption information for stable forecasting performance, even in the context of crisis fluctuations and geopolitical risk shocks. Furthermore, we apply forecast encompassing tests and variable selection to statistically investigate the predictive information. By analyzing energy consumption characteristics, we contribute to the economic growth hypothesis at the level of energy consuming sectors and provide new insights into GDP forecasting.

A novel CGBoost deep learning algorithm for coseismic landslide susceptibility prediction

The accurate prediction of landslide susceptibility shortly after a violent earthquake is quite vital to the emergency rescue in the 72-h “golden window”. However, the limited quantity of interpreted landslides shortly after a massive earthquake makes landslide susceptibility prediction become a challenge. To address this gap, this work suggests an integrated method of Crossing Graph attention network and xgBoost (CGBoost). This method contains three branches, which extract the interrelations among pixels within a slope unit, the interrelations among various slope units, and the relevance between influencing factors and landslide probability, respectively, and obtain rich and discriminative features by an adaptive fusion mechanism. Thus, the difficulty of susceptibility modeling under a small number of coseismic landslides can be reduced. As a basic module of CGBoost, the proposed Crossing graph attention network (Crossgat) could characterize the spatial heterogeneity within and among slope units to reduce the false alarm in the susceptibility results. Moreover, the rainfall dynamic factors are utilized as prediction indices to improve the susceptibility performance, and the prediction index set is established by terrain, geology, human activity, environment, meteorology, and earthquake factors. CGBoost is applied to predict landslide susceptibility in the Gorkha meizoseismal area. 3.43% of coseismic landslides are randomly selected, of which 70% are used for training, and the others for testing. In the testing set, the values of Overall Accuracy, Precision, Recall, F1-score, and Kappa coefficient of CGBoost attain 0.9800, 0.9577, 0.9999, 0.9784, and 0.9598, respectively. Validated by all the coseismic landslides, CGBoost outperforms the current major landslide susceptibility assessment methods. The suggested CGBoost can be also applied to landslide susceptibility prediction in new earthquakes in the future.

Edge geo chromatic number of a graph

The Edge Geodetic Number is also known as the smallest size among all sets of edges that make up Edge Geodetic sets and is represented by the symbol g1(G). Assuming G is a finite connected graph, we can define a set S contained in V(G) as an Edge Geodetic set if, for any pair of vertices u and v in set S, every edge in G lies on the shortest path between u and v. A set C contained in E(G) is referred to as a chromatic index set when it contains all of the proper k-edge colors of G. The chromatic index is determined by the set's lowest cardinality among its edges. The "Chromatic Index Number" is a term used to refer to the collection of these minimum cardinality chromatic index values and is represented by the symbol chi'(G). By combining an Edge Geodetic set with a Chromatic Index set, the Edge Geo Chromatic set of G is created, providing an innovative concept. The Edge Geo Chromatic Number, abbreviated as X, is the least cardinality among all Edge Geo Chromatic sets of G. In essence, an Edge Geodetic set and a Chromatic Index set combine to form an Edge Geo Chromatic graph. We talk about an edge geo chromatic linked graph with n orders. For a number of common graphs, we have computed the Edge Geo Chromatic Number and established its bounds. Furthermore, we have shown that when G represents a graph of diameter d, then chi'_gc(G) lessthan or equal to n - d +2.

Multi-loop Nesting Algorithm and Response Analysis of Cable Forces of Long Span Cantilever Cast Arch Bridges during Construction

The existing calculation process of the cantilever cast arch-cable force has a poor fit with the actual process, leading to the lack of good parameter corrections. To improve the overall control quality of the linearity and stress of the arch ring, there is an urgent need for a solution method with higher flexibility and better practicability. Combined with the existing research results, this study proposes a multi-loop nesting algorithm. The algorithm decomposes the whole construction process into individual subsystem control modules, and sets the control indexes of stress and displacement in individual control modules. Subsequently, the analysis and calculation of other modules are completed according to the construction sequence until structure closure. Finally, we determine whether the overall construction control indexes meet the requirements. According to the findings, the results obtained by this algorithm meet the design requirements, and its applicability is verified. Compared with other algorithms, the algorithm is more effective in controlling the stress and deformation of the arch ring during the construction process. This algorithm solves the dispersion between structural systems in previous calculations and has more flexible parameter and control index settings. Additionally, the calculation control idea of this algorithm can be further extended to the construction control of the “cable-beam” cantilever structure.

Constant Sum Group Flows of Graphs

As an analogous concept of a nowhere-zero flow for directed graphs, zero-sum flows and constant-sum flows are defined and studied in the literature. For an undirected graph, a zero-sum flow (constant-sum flow resp.) is an assignment of nonzero integers to the edges such that the sum of the values of all edges incident with each vertex is zero (constant h resp.), and we call it a zero-sum k-flow (h-sum k-flow resp.) if the values of the edges are less than k. We extend these concepts to general constant-sum A-flow, where A is an Abelian group, and consider the case A=Zk the additive Abelian cyclic group of integer congruences modulo k with identity 0. In the literature, a graph is alternatively called Zk-magic if it admits a constant-sum Zk-flow, where the constant sum is called a magic sum or an index for short. We define the set of all possible magic sums such that G admits a constant-sum Zk-flow to be Ik(G) and call it the magic sum spectrum, or for short, the index set of G with respect to Zk. In this article, we study the general properties of the magic sum spectrum of graphs. We determine the magic sum spectrum of complete bipartite graphs Km,n for m≥n≥2 as the additive cyclic subgroups of Zk generated by kd, where d=gcd(m−n,k). Also, we show that every regular graph G with a perfect matching has a full magic sum spectrum, namely, Ik(G)=Zk for all k≥3. We characterize a 3-regular graph so that it admits a perfect matching if and only if it has a full magic sum spectrum, while an example is given for a 3-regular graph without a perfect matching which has no full magic sum spectrum. Another example is given for a 5-regular graph without a perfect matching, which, however, has a full magic sum spectrum. In particular, we completely determine the magic sum spectra for all regular graphs of even degree. As a byproduct, we verify a conjecture raised by Akbari et al., which claims that every connected 4k-regular graph of even order admits a 1-sum 4-flow. More open problems are included.

Graphene-based phononic crystal lenses: Machine learning-assisted analysis and design

The advance of artificial intelligence and graphene-based composites brings new vitality into the conventional design of acoustic lenses which suffers from high computation cost and difficulties in achieving precise desired refractive indices. This paper presents an efficient and accurate design methodology for graphene-based gradient-index phononic crystal (GGPC) lenses by combing theoretical formulations and machine learning methods. The GGPC lenses consist of two-dimensional phononic crystals possessing square unit cells with graphene-based composite inclusions. The plane wave expansion method is exploited to obtain the dispersion relations of elastic waves in the structures and then establish the data sets of the effective refractive indices in structures with different volume fractions of graphene fillers in composite materials and filling fractions of inclusions. Based on the database established by the theoretical formulation, genetic programming, a superior machine learning algorithm, is introduced to generate explicit mathematical expressions to predict the effective refractive indices under different structural information. The design of GGPC lenses is conducted with the assistance of the machine learning prediction model, and it will be illustrated by several typical design examples. The proposed design method offers high efficiency, accuracy as well as the ability to achieve inverse design of GGPC lenses, thus significantly facilitating the development of novel phononic crystal lenses and acoustic energy focusing.

Dominant Characteristics of Subject Categories in a Multiple-Category Hierarchical Scheme: A Case Study of Scopus

The Scopus journal classification method, known as All Science Journal Classification (ASJC), follows a hierarchical organization of subject categories: minor, major, and supergroups. At the minor level, journals are assigned to one or more subject categories. We refer to this classification scheme as a multiple-category hierarchical scheme. The objective of this study is to investigate the dominant characteristics of subject categories within the Scopus database and quantify their dominance using various subject indices. To conduct the study, we formulated a set of subject category indices, including the Number of Journals (J), Total Instances of Subject Categories (SC), Number of Unique Subject Categories (USC), and Dominance Index (DOMI). The results showed that high DOMI values in subject categories indicate specialization and limited associations with other fields. There were minimal correlations between DOMI and other subject category indices like J, SC, and USC, demonstrating their uniqueness and independence. The study also revealed that subject categories within the Health Sciences exhibited higher DOMI values and greater specialization compared to those in the Physical Sciences, indicating a pronounced dominance in Health Sciences minor categories. Finally, minor subject categories exhibited more variation in subject category indices compared to their upper-level subject categories, highlighting the intricate variations within the hierarchical system of the Scopus classification. These findings have implications for researchers, emphasizing the need to consider a subject category’s dominance and associations when selecting journals for their research.

Climatic effects on landscape multifunctionality in urban parks: a view for integrating ecological supply and human benefits

The rapid and relentless development of urban areas highlights the importance of landscape multifunctionality. However, there is limited research on the temporal dynamics and climatic effects of urban landscape multifunctionality. This study aimed to address this gap by analyzing the features of multiple landscape functions triggered by seasonal climate change in different urban park types. In this study, we investigated five typical urban landscape functions (alleviating urban heat islands, vegetation growth, biodiversity promotion, alleviation of waterlogging, and provision of recreational activities) by establishing a set of indices: ecological supply capability (SP ), proportion of ecological supply (SPP ), capability of human benefits (BP ), and human benefits efficiency (BEP ) of urban parks. The average SP of the landscape functions was 58% in summer and 46% in winter. During the transition from summer to winter, urban parks witnessed a significant decrease in SPP for alleviating the urban heat island, dropping from 34% to 5%. The primary landscape functions shifted from alleviating the urban heat island (34%) and providing recreation (29%) to providing recreation (38%) and biodiversity promotion (29%). Concerning park types, nature parks provided the highest SP , whereas community parks provided the highest BEP . This study has useful implications for landscape management in urban parks, particularly regarding timely adjustments across seasonal climates. It is possible to promote sustainable and effective human well-being by maximizing landscape functions.

The Impact of Foreign Trade in the Graduation Process of Asian Least-Developed Countries (LDCs)

AbstractThe importance of development studies comes from the need to assess and solve economic problems. Graduation from LDC status represents an important milestone in their development path. This research tries to deepen on the relationship between the fulfillment of the “graduation criteria” established by the United Nations and the evolution of the foreign trade indices of a group of Asian LDCs about to graduate (Bangladesh, Bhutan, Laos, Timor-Leste, Nepal, and Myanmar), checking how trade, one of its engines for economic development, has involved during the last years and, specifically, on their way to graduation. First, the characteristics of the LDCs and the criteria to exclude them from the list are analyzed. Second, a set of indices are presented to find out the trade flows throughout the period observed. Finally, conclusions and future lines of research are proposed. The results show that all the countries studied have succeeded in expanding their share in world trade. The high participation of Bangladesh is justified by the size of its economy and its weight within the textile trade. Regarding diversification, all of countries present a highly concentrated pattern of exports and their exchanges are carried out with few countries. This lack of trade diversification places them in a vulnerable position. The relative trade balance index indicates that all of them are competitive with their trading partners in the products analyzed and the six have comparative advantage. To conclude, the analysis confirms that the trade structure of the LDCs considered has improved, but with differences due to their characteristics.

Predicting bird diversity through acoustic indices within the Atlantic Forest biodiversity hotspot

The increasing conversion of natural areas for anthropic land use has been a major cause of habitat loss, destabilizing ecosystems and leading to a biodiversity crisis. Passive acoustic sensors open the possibility of remotely sensing fauna on large spatial and temporal scales, improving our understanding of the current state of biodiversity and the effects of human influences. Acoustic indices have been widely used and tested in recent years, with an aim towards understanding the relationship between indices and the acoustic activity of several taxa in different types of environments. However, studies have shown divergent relationships between acoustic indices and the vocal activity of most soniferous taxa. A combination of indices has, in turn, been reported as a promising tool for representing biodiversity in different contexts. We used uni- and bivariate models to test different combinations of 8 common indices in relation to bird assemblage metrics. We recorded twenty-two study sites in Brazil’s Atlantic Forest and three different types of environments in each site (forest, pasture, and swamp). Our results showed that 1) the best acoustic indices for explaining bird richness, abundance, and diversity were Bioacoustic and Acoustic Complexity; 2) the type of environment (forest, pasture, and swamp) influenced the performance of acoustic indices in explaining bird biodiversity, with the highest score model (biggest R2 value) being a combination between Acoustic Diversity and Bioacoustic indices. Our results do support the use of acoustic indices in monitoring the acoustic activity of birds, but combining indices is encouraged since it provided the best results. However, given the divergence we found across environments, we recommend that sets of indices are tested to determine which of them best describe the biodiversity pattern models for a specific habitat. Based on our results, we propose that biodiversity patterns can be predicted through acoustic patterns. However, the level of confidence will depend on the acoustic index used and on focal taxa of interest (i.e., birds, amphibians, insects, and mammals).