Journal articles on the topic 'Structural complexity index'
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Beckschäfer, Philip, Philip Mundhenk, Christoph Kleinn, Yinqiu Ji, Douglas W. Yu, and Rhett D. Harrison. "Enhanced Structural Complexity Index: An Improved Index for Describing Forest Structural Complexity." Open Journal of Forestry 03, no. 01 (2013): 23–29. http://dx.doi.org/10.4236/ojf.2013.31005.
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Sabatini, FM, S. Burrascano, F. Lombardi, G. Chirici, and C. Blasi. "An index of structural complexity for Apennine beech forests." iForest - Biogeosciences and Forestry 8, no. 3 (June 1, 2015): 314–23. http://dx.doi.org/10.3832/ifor1160-008.
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Hossny, Hossam E., Ahmed H. Ibrahim, and Abeer Elnady. "Assessment of Construction Project Complexity." Open Civil Engineering Journal 15, no. 1 (December 28, 2021): 414–23. http://dx.doi.org/10.2174/1874149502115010414.
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Objective: Project complexity is a crucial factor in project management that presents auxiliary obstacles to reaching project objectives (cost, time, safety, and quality). This study aims at understanding project complexity and factors affecting project complexity. The overall objective of the study is to determine the nature of complexity and characteristics, identify the important complex factors that influence the complexity of the project, factor weight of the complex factors, and develop a proposed construction complexity index (CCI). Methods: According to the literature review, the Analytic Hierarchy Process (AHP) method is used to measure the affecting factors of project complexity. Results: This paper developed an index to measure complexity based on factor weights called construction complexity index (CCI). The validity of this index was verified by studying 3 cases. The construction complexity index (CCI) proposed here allows measuring the complexity of the projects in Egypt. The results of this paper provide guidelines on how to successfully manage the complexity of the project. Conclusion: Project complexity management relates to the challenge of dealing with technical competence, professional diversity, uncertainties, and unforeseen events in project implementation. Project managers, who are critical to effectiveness or failure, need skills such as adaptation, creativity, and flexibility to meet this challenge. Therefore, this study provides guidelines to help practitioners to develop their capabilities in managing complex projects. Moreover, this paper enables participants to identify factors affecting the complexity of projects and how to calculate this complexity through the complex index. The outcomes of this study can be used by practitioners to develop a complexity assessment and management tool, which would enable industry practitioners to allocate resources effectively on complex construction projects. This research aimed to develop a measure by which the complexity of construction projects in Egypt can be evaluated and establish guidelines on avoiding complexity in projects.
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Pasher, Jon, and Douglas J. King. "Development of a forest structural complexity index based on multispectral airborne remote sensing and topographic dataThis article is one of a selection of papers from Extending Forest Inventory and Monitoring over Space and Time." Canadian Journal of Forest Research 41, no. 1 (January 2011): 44–58. http://dx.doi.org/10.1139/x10-175.
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This paper presents development of a multivariate forest structural complexity index based on relationships between field-based structural variables and geospatial data. Remote sensing has been widely used to model individual forest structural attributes at many scales. As opposed to, or in addition to, individual structural parameters such as leaf area index or tree height, overall structural complexity information can enhance forest inventories and provide a variety of information to forest managers, including identifying damage and disturbance as well as indicators of habitat or biodiversity. In this study, a multivariate modelling technique, redundancy analysis, was implemented to derive a model incorporating both horizontal and vertical structural attributes as predicted by an ensemble of high-resolution multispectral airborne imagery and topographic variables. The first redundancy analysis axis of the final model explained 35% of the total variance of the field variables and was used as the complexity index. With a root mean squared error of 19.9%, the model was capable of differentiating four to five relative levels of complexity. This paper presents the forest ecological and modelling aspects of the research. A related paper presents the remote sensing aspects, including application of the model to map predicted structural complexity, map validation, and testing of the method at multiple scales.
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Gebrerufael, Samson Gebresilasie. "Dynamics of Product Complexity in Africa: Structural Estimation Using Structuralists Model." Journal of Heterodox Economics 4, no. 1 (June 1, 2017): 11–35. http://dx.doi.org/10.1515/jheec-2017-0002.
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Abstract Applying the linear LAS (Latin American Structuralists) technological intensity model in Africa, this paper presents African nations are still diversifying their outputs towards the ubiquitous (fewer complexes) products. Put it simple, using the economic complexity index of Africa (explanatory variable) as a proxy for the technological intensity in Africa and per capita GDP gap (explanatory variable) as a proxy for technology gap, the paper presents a significant and positive relationship between economic complexity index of Africa and the time derivative of the economic complexity index of Africa (the explained variable). This implies that “weak” effort African nations exerted so far in diversifying their outputs towards the less ubiquitous commodities and absence of “automatic catch up tendency” (unlike what is presupposed by the mainstream neo-classical growth models). The linear panel data regression is employed on sample of 23 African economies and OECD member economies for the period 1996-2014.
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Põldveer, Eneli, Aleksei Potapov, Henn Korjus, Andres Kiviste, John A. Stanturf, Tauri Arumäe, Ahto Kangur, and Diana Laarmann. "The structural complexity index SCI is useful for quantifying structural diversity of Estonian hemiboreal forests." Forest Ecology and Management 490 (June 2021): 119093. http://dx.doi.org/10.1016/j.foreco.2021.119093.
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Rodrigues, Lenise Chagas, Fabricio Simões Correa, Leandro Juen, and Maria Cristina dos Santos-Costa. "Effects of pond structural complexity on the reproduction of Physalaemus ephippifer (Anura, Leptodactylidae)." Animal Biology 68, no. 4 (2018): 405–15. http://dx.doi.org/10.1163/15707563-17000152.
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Abstract Habitat structure is a factor that strongly affects the distribution of organisms. Habitats with high structural complexity provide a high number of microhabitats, allowing the coexistence of species with different behavioral, ecological and physiological requirements. We analyzed the effects of structural complexity of ponds on the number of males and foam nests of Physalaemus ephippifer, and the substrates to which individuals attach their foam nests. We sampled 41 ponds and recorded the number of individuals of P. ephippifer and environmental data (type of vegetation in, adjacent and around the pond; type of bottom substrate in the pond) to measure the degree of structural complexity of the ponds through an index ranging between 0 and 1. We found a positive influence of pond structural complexity on mean number of calling males, but not on number of foam nests. We found most foam nests attached to gramineans and herbaceous plants. Vegetation is an important component of habitats with high complexity, providing refuges for adults and tadpoles. The index was an efficient tool to measure habitat structural complexity, and may be used in further studies with other species.
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Gutierrez-Clellen, Vera F., and Richard Hofstetter. "Syntactic Complexity in Spanish Narratives." Journal of Speech, Language, and Hearing Research 37, no. 3 (June 1994): 645–54. http://dx.doi.org/10.1044/jshr.3703.645.
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Syntactic complexity in the movie retellings of 77 school-age Spanish-speaking children was examined using a structural constituent analysis. The results demonstrated developmental differences in the length of T-units, index of subordination, use of relative clauses, and prepositional phrases. There were also differences in the length of T-units, use of nominal clauses, and adverbial phrases across Spanish language groups. The analysis underscores the significance of subordination as a cohesive device and as an indicator of narrative proficiency.
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McElhinny, C., P. Gibbons, and C. Brack. "An objective and quantitative methodology for constructing an index of stand structural complexity." Forest Ecology and Management 235, no. 1-3 (November 2006): 54–71. http://dx.doi.org/10.1016/j.foreco.2006.07.024.
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Modrak, Vladimir, and David Marton. "Complexity Metrics for Assembly Supply Chains: A Comparative Study." Advanced Materials Research 629 (December 2012): 757–62. http://dx.doi.org/10.4028/www.scientific.net/amr.629.757.
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In this paper, we study the complexity metrics for systematically generated assembly supply chains structures. We define three structural complexity indicators, such as the index of vertex degree, the supply chain length and the flow complexity. By a comparative study of 190 mathematically selected supply chain networks, we obtained Spearman correlation coefficients among three defined metrics and find some interesting results.
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Roff, George, Jennifer Joseph, and Peter J. Mumby. "Multi-decadal changes in structural complexity following mass coral mortality on a Caribbean reef." Biogeosciences 17, no. 23 (December 1, 2020): 5909–18. http://dx.doi.org/10.5194/bg-17-5909-2020.
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Abstract. In recent decades, extensive mortality of reef-building corals throughout the Caribbean region has led to the erosion of reef frameworks and declines in biodiversity. Using field observations, structural models, and high-precision U–Th dating methods, we quantify changes in structural complexity in the major framework-building coral Orbicella annularis over a 20-year period at Long Caye (Belize). Despite extensive mortality following the mass coral bleaching event of 1998, the structural complexity of frameworks remained largely unchanged between 1998 (rugosity index, R, of 2.35±0.1) and 2018 (R of 2.29±0.1). Colony-scale structural complexity was maintained, as the rapid growth of surviving ramets (0.69±0.1 cm yr−1) offset the slower bioerosion of dead ramets (-0.11±0.16 cm yr−1). Despite the apparent stability of the structural complexity at colony scales, bioerosion of individual dead ramets over 2 decades led to declines in microhabitat complexity, with an overall reduction in the depth of microhabitats within frameworks. Altered microhabitat complexity appears to have negative effects on cryptic fauna, with the grazing urchin Echinometra viridis declining from 1.5±0.4 individuals m−2 in 1998 to 0.02± individuals m−2 in 2018. Changes in microhabitat complexity have the potential to alter ecological interactions that can impact recovery dynamics on coral reefs in ways that are undetectable using traditional rugosity metrics of structural complexity.
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Peterson, Chris. "Damage Diversity as a Metric of Structural Complexity after Forest Wind Disturbance." Forests 10, no. 2 (January 23, 2019): 85. http://dx.doi.org/10.3390/f10020085.
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This study presents a new metric for quantifying structural complexity using the diversity of tree damage types in forests that have experienced wind disturbance. Structural complexity studies of forests have to date not incorporated any protocol to address the variety of structural damage types experienced by trees in wind disturbances. This study describes and demonstrates such a protocol. Damage diversity, defined as the richness and evenness of types of tree damage, is calculated analogously to species diversity using two common indices, and termed a ‘Shannon Damage Heterogeneity Index’ (Sh-DHI) and an inverse Simpson Damage Heterogeneity Index (iSi-DHI). The two versions of the DHI are presented for >400 plots across 18 distinct wind disturbed forests of eastern North America. Relationships between DHI and pre-disturbance forest species diversity and size variability, as well as wind disturbance severity, calculated as the fraction of basal area downed in a wind disturbance event, are examined. DHIs are only weakly related to pre-disturbance tree species diversity, but are significantly positively related to pre-disturbance tree size inequality (size diversity). Damage diversity exhibits a robust curvilinear relationship to severity; both versions of the DHI show peaks at intermediate levels of wind disturbance severity, suggesting that in turn structural complexity may also peak at intermediate levels of severity.
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Famiglietti, Caroline A., T. Luke Smallman, Paul A. Levine, Sophie Flack-Prain, Gregory R. Quetin, Victoria Meyer, Nicholas C. Parazoo, et al. "Optimal model complexity for terrestrial carbon cycle prediction." Biogeosciences 18, no. 8 (April 30, 2021): 2727–54. http://dx.doi.org/10.5194/bg-18-2727-2021.
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Abstract. The terrestrial carbon cycle plays a critical role in modulating the interactions of climate with the Earth system, but different models often make vastly different predictions of its behavior. Efforts to reduce model uncertainty have commonly focused on model structure, namely by introducing additional processes and increasing structural complexity. However, the extent to which increased structural complexity can directly improve predictive skill is unclear. While adding processes may improve realism, the resulting models are often encumbered by a greater number of poorly determined or over-generalized parameters. To guide efficient model development, here we map the theoretical relationship between model complexity and predictive skill. To do so, we developed 16 structurally distinct carbon cycle models spanning an axis of complexity and incorporated them into a model–data fusion system. We calibrated each model at six globally distributed eddy covariance sites with long observation time series and under 42 data scenarios that resulted in different degrees of parameter uncertainty. For each combination of site, data scenario, and model, we then predicted net ecosystem exchange (NEE) and leaf area index (LAI) for validation against independent local site data. Though the maximum model complexity we evaluated is lower than most traditional terrestrial biosphere models, the complexity range we explored provides universal insight into the inter-relationship between structural uncertainty, parametric uncertainty, and model forecast skill. Specifically, increased complexity only improves forecast skill if parameters are adequately informed (e.g., when NEE observations are used for calibration). Otherwise, increased complexity can degrade skill and an intermediate-complexity model is optimal. This finding remains consistent regardless of whether NEE or LAI is predicted. Our COMPLexity EXperiment (COMPLEX) highlights the importance of robust observation-based parameterization for land surface modeling and suggests that data characterizing net carbon fluxes will be key to improving decadal predictions of high-dimensional terrestrial biosphere models.
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E.G., Kavilal, Shanmugam Prasanna Venkatesan, and Joshi Sanket. "An integrated interpretive structural modeling and a graph-theoretic approach for measuring the supply chain complexity in the Indian automotive industry." Journal of Manufacturing Technology Management 29, no. 3 (April 16, 2018): 478–514. http://dx.doi.org/10.1108/jmtm-03-2017-0032.
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Purpose Easily employable quantitative supply chain complexity (SCC) measures considering the significant dimensions of complexity as well as the drivers that represent those dimensions are limited in the literature. The purpose of this paper is to propose an integrated interpretive structural modeling (ISM) and a graph-theoretic approach to quantify SCC by a single numerical index considering the interdependence and the inheritance of the SCC drivers. Design/methodology/approach In total, 18 SCC drivers identified from the literature are clustered according to the significant dimensions of complexity. The interdependencies established through ISM and inheritance values of SCC drivers are mapped into a Variable Permanent Matrix (VPM). The permanent function of this VPM is then computed and the resulting single numerical index is the measure of SCC. Findings A scale is proposed by computing the minimum and maximum threshold values of SCC with the help of expert opinions of the Indian automotive industry. The complexity of commercial and passenger vehicle sectors within the automotive industry is measured and compared using the proposed scale. From the results, it is identified that the number of suppliers, increase in spare-parts due to shortened product life-cycle and demand uncertainties increase the SCC of the passenger vehicle sector, while number of parts, products and processes, variety of products and process and unreliability of suppliers increase the complexity of the commercial vehicle sector. The result indicates that various SCC drivers have a different impact on determining the SCC level of these two sectors. Originality/value The authors propose an integrated method that can be readily applied to measure and quantify SCC considering the significant dimensions of complexity as well as the interdependence and the inheritance of the SCC drivers that contribute to those dimensions. This index further helps to compare the complexity of the supply chain which varies between industries.
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Seidel, Dominik, Peter Annighöfer, Christian Ammer, Martin Ehbrecht, Katharina Willim, Jan Bannister, and Daniel P. Soto. "Quantifying Understory Complexity in Unmanaged Forests Using TLS and Identifying Some of Its Major Drivers." Remote Sensing 13, no. 8 (April 14, 2021): 1513. http://dx.doi.org/10.3390/rs13081513.
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The structural complexity of the understory layer of forests or shrub layer vegetation in open shrublands affects many ecosystem functions and services provided by these ecosystems. We investigated how the basal area of the overstory layer, annual and seasonal precipitation, annual mean temperature, as well as light availability affect the structural complexity of the understory layer along a gradient from closed forests to open shrubland with only scattered trees. Using terrestrial laser scanning data and the understory complexity index (UCI), we measured the structural complexity of sites across a wide range of precipitation and temperature, also covering a gradient in light availability and basal area. We found significant relationships between the UCI and tree basal area as well as canopy openness. Structural equation models (SEMs) confirmed significant direct effects of seasonal precipitation on the UCI without mediation through basal area or canopy openness. However, annual precipitation and temperature effects on the UCI are mediated through canopy openness and basal area, respectively. Understory complexity is, despite clear dependencies on the available light and overall stand density, significantly and directly driven by climatic parameters, particularly the amount of precipitation during the driest month.
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Ibrahim, Issah, Mohammad Hossain Mohammadi, Vahid Ghorbanian, and David Lowther. "Correlating structural complexity and acoustic noise performance of electric motors." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 41, no. 3 (March 29, 2022): 925–37. http://dx.doi.org/10.1108/compel-03-2021-0094.
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Purpose Acoustic noise is a crucial performance index in the design of electrical machines. Due to the challenges associated with modelling a complete motor, the stator is often used to estimate the sound power in the prototyping stage. While this approach greatly reduces lengthy simulations, the actual sound power of the motor may not be known. But, from the acoustic noise standpoint, not much is known about the correlation between the stator and complete motor. This paper, therefore, aims to use the sound pressure levels of the stator and the full motor to investigate the existence of correlations in the interior permanent magnet synchronous motor. Design/methodology/approach A multiphysics simulation framework is proposed to evaluate the sound pressure levels of multiple motor geometries in a given design space. Then, a statistical analysis is performed on the calculated sound pressure levels of each geometry over a selected speed range to compare the correlation strength between the stator and the full model. Findings It was established that the stator and the complete motor model are moderately correlated. As such, a reliance on the stator sound power for design and optimization routines could yield inaccurate results. Originality/value The main contribution involves the use of statistical tools to study the relationship between sound pressure levels associated with the stator geometry and the complete electric motor by increasing the motor sample size to capture subtle acoustic correlation trends in the design space of the interior permanent magnet synchronous motor.
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Bell, SS, RA Brooks, and WE Ellis. "Structural spacing and the determination of habitat complexity: examining the Bartholomew et al. (2000) index." Marine Ecology Progress Series 248 (2003): 293–95. http://dx.doi.org/10.3354/meps248293.
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Buscema, Massimo, Masoud Asadi-Zeydabadi, Weldon Lodwick, and Marco Breda. "The H0 function, a new index for detecting structural/topological complexity information in undirected graphs." Physica A: Statistical Mechanics and its Applications 447 (April 2016): 355–78. http://dx.doi.org/10.1016/j.physa.2015.12.055.
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Du Preez, Cherisse. "A new arc–chord ratio (ACR) rugosity index for quantifying three-dimensional landscape structural complexity." Landscape Ecology 30, no. 1 (November 15, 2014): 181–92. http://dx.doi.org/10.1007/s10980-014-0118-8.
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Liu, Yan, Wenjing Tong, Qianqian Li, Fuyi Yao, Yan Li, Hong Xian Li, and Jiaxin Huang. "Study on Complexity of Precast Concrete Components and Its Influence on Production Efficiency." Advances in Civil Engineering 2022 (April 14, 2022): 1–18. http://dx.doi.org/10.1155/2022/9926547.
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Prefabricated construction has been well recognized for its benefits, including accelerated construction cycle time and improved sustainability. However, low efficiency in the production of precast concrete components due to component and production complexity has not been sufficiently addressed in previous research. This paper explores the complexity of precast concrete components by establishing complexity indices and evaluating their influence on production efficiency. First, referring to research on product complexity in the machinery manufacturing industry, we define the complexity of precast concrete components in the construction industry. Then, based on a literature review, field studies, and expert interviews, we systematically construct the complexity indices of precast concrete components using the three-stage coding method, Grounded Theory. The overall complexity index system for precast concrete components constructed comprises 16 constituent complexity indices in three dimensions (i.e., structural complexity of the component, production complexity, and management complexity). The relationship between complexity indices and production efficiency is then explored using structural equation model analysis based on the data collected through a questionnaire survey. The results reveal that complexity indices have a significant impact on the production efficiency for precast concrete components, where the number of embedded parts, waiting time in production, operating proficiency of workers, and degree of automation of the production line are found to be the most influential complexity indices. This study provides a foundation upon which production managers improve production efficiency for precast concrete components based on an analysis of their product complexity.
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Arseniou, Georgios, David W. MacFarlane, and Dominik Seidel. "Measuring the Contribution of Leaves to the Structural Complexity of Urban Tree Crowns with Terrestrial Laser Scanning." Remote Sensing 13, no. 14 (July 14, 2021): 2773. http://dx.doi.org/10.3390/rs13142773.
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Trees have a fractal-like branching architecture that determines their structural complexity. We used terrestrial laser scanning technology to study the role of foliage in the structural complexity of urban trees. Forty-five trees of three deciduous species, Gleditsia triacanthos, Quercus macrocarpa, Metasequoia glyptostroboides, were sampled on the Michigan State University campus. We studied their structural complexity by calculating the box-dimension (Db) metric from point clouds generated for the trees using terrestrial laser scanning, during the leaf-on and -off conditions. Furthermore, we artificially defoliated the leaf-on point clouds by applying an algorithm that separates the foliage from the woody material of the trees, and then recalculated the Db metric. The Db of the leaf-on tree point clouds was significantly greater than the Db of the leaf-off point clouds across all species. Additionally, the leaf removal algorithm introduced bias to the estimation of the leaf-removed Db of the G. triacanthos and M. glyptostroboides trees. The index capturing the contribution of leaves to the structural complexity of the study trees (the ratio of the Db of the leaf-on point clouds divided by the Db of the leaf-off point clouds minus one), was negatively correlated with branch surface area and different metrics of the length of paths through the branch network of the trees, indicating that the contribution of leaves decreases as branch network complexity increases. Underestimation of the Db of the G. triacanthos trees, after the artificial leaf removal, was related to maximum branch order. These results enhance our understanding of tree structural complexity by disentangling the contribution of leaves from that of the woody structures. The study also highlighted important methodological considerations for studying tree structure, with and without leaves, from laser-derived point clouds.
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Yameogo, Nadege Desiree, Tiguene Nabassaga, Abebe Shimeles, and Mthuli Ncube. "Diversification and Sophistication as drivers of structural transformation for Africa: The Economic Complexity Index of African Countries." Journal of African Development 16, no. 2 (October 1, 2014): 1–39. http://dx.doi.org/10.5325/jafrideve.16.2.0001.
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Abstract African countries have achieved impressive growth performance during the recent years despite the multiple crises the western world is experiencing. However, this growth has not been inclusive for several reasons. It has been driven mainly by the extractive industry at the detriment of the industrial and manufacturing sectors. These sectors contribution has even stagnated during the last fifteen years to least than 10% of the continent's GDP. Because much of the efforts were put in the extractive industry, and the industrial sector including the manufacturing were neglected for long time, it has resulted that most African countries productive structure have remained weakly sophisticated and diversified. The productive structures have not benefited from the recent growth observed across the continent. Since Adam smith (1776), it is recognized that the level of wealth of a nation depends mainly on the lever of knowledge that the society holds. This is translated in the nation's productive structure and the products it make. By exporting mainly commodities and raw materials that do not require any advanced technology, African countries have not yet been able to structurally transform their economies. Yet, it is acknowledges in the literature that development and growth are a process of structural transformation whereby resources were transform from lower productivity activities to higher productivity activities. And this transformation has not yet been observed in African societies. This paper attempted to measure the level of complexity of African economies by adopting the same approach recently introduced by Hidalgo et al. (2007) and Hidalgo and Hausmann (2009). We generated a large database that includes detailed information related to technology intensiveness of African countries exports, their revealed comparative advantages, indicators related to diversity, ubiquity, and economic and product complexity. We found that not only African economies are not complex. Their exports are weakly diversified and weakly sophisticated. This could contribute to explain why the recent growth has not been inclusive. This study is a starting point and could be extended to deeper macro-econometric analysis which will provide policy recommendations to African countries on which areas they should focus their efforts in order to really transform their economies and create sustainable prosperity for the majority of their population.
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Hniezdovskyi, Oleksii, Oleksii Kudin, Yuriy Belokon, Dmytro Kruglyak, and Sergii Ilin. "Designing an object-oriented architecture for the finite element simulation of structural elements." Eastern-European Journal of Enterprise Technologies 6, no. 2 (120) (December 30, 2022): 78–84. http://dx.doi.org/10.15587/1729-4061.2022.268018.
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This paper reports the development of an architecture and software implementation of the library of classes for the finite-element analysis of problems in the theory of elasticity with an open-source code. The practical necessity of such systems is due to the fact that in modern equipment there are new types of materials whose structural elements' calculation has certain features. As a result, it is necessary to update the relevant scientific software or even devise a new one. A flexible software architecture is designed to reduce the time and complexity of such updates. Existing implementations of the method of finite elements with open source have been analyzed: it was revealed that there are no systems aimed at the most flexible and user-friendly architecture. The system of abstract classes proposed in the current work corresponds to known SOLID principles of object-oriented design and makes it possible to scale the already developed analysis program for new tasks in an easy and understandable way. To test the quality of the developed system from the point of view of software engineering, the maintainability index and cyclomatic complexity code metrics were used. The values of these metrics for the modules of the PyFEM system core vary in the following ranges: from 1 to 18 for the maintainability index, and from 22 to 100 for cyclomatic complexity. PyFEM testing was performed on the task of determining the stressed-strained state of the turbine rotor blade. Due to the ease of implementation, it was possible to build a set of effective and intuitive classes that make it possible to solve numerically the static and dynamic problems in the theory of elasticity. The developed class library can be used in the development of both universal and specialized software designed to analyze multiphysics problems.
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Chen, Wei, Man Zhou, and Kai Man Chen. "Study on System Complexity of Mega Infrastructure Projects System – Taking Wuhan East Lake Channel Project as Case Study." Advanced Materials Research 1079-1080 (December 2014): 1211–15. http://dx.doi.org/10.4028/www.scientific.net/amr.1079-1080.1211.
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The mega-infrastructure projects system complexity will increase along with the growing rate of stakeholders` quantity, changeable construction environment and multidisciplinary technical implementation. The research aims to analyze the characteristics of this kind of projects progress in the time dimension and evaluate the complexity of the mega infrastructure project system. The complexity evaluation system including 18 measurement indicators is proposed based on the theory of complex system and the structural equation model are applied to be calculated the solution which indicated the key factors and measurement of the mega-infrastructure projects. The conclusion has been drawn and tested by the Wuhan East Lake Channel Project as case study which showed that the measure index and the evaluation model can be applied in evaluating complexity of the mega-infrastructural projects scientifically.
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Tang, Juan, and Yongsheng Rao. "A New Block Structural Index Reduction Approach for Large-Scale Differential Algebraic Equations." Mathematics 8, no. 11 (November 18, 2020): 2057. http://dx.doi.org/10.3390/math8112057.
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A new generation of universal tools and languages for modeling and simulation multi-physical domain applications has emerged and became widely accepted; they generate large-scale systems of differential algebraic equations (DAEs) automatically. Motivated by the characteristics of DAE systems with large dimensions, high index or block structures, we first propose a modified Pantelides’ algorithm (MPA) for any high order DAEs based on the Σ matrix, which is similar to Pryce’s Σ method. By introducing a vital parameter vector, a modified Pantelides’ algorithm with parameters has been presented. It leads to a block Pantelides’ algorithm (BPA) naturally which can immediately compute the crucial canonical offsets for whole (coupled) systems with block-triangular form. We illustrate these algorithms by some examples, and preliminary numerical experiments show that the time complexity of BPA can be reduced by at least O(ℓ) compared to the MPA, which is mainly consistent with the results of our analysis.
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Chen, Qiu-Feng, Xiao-Hong Zhang, Tian-Xiu Zou, Nao-Xin Huang, and Hua-Jun Chen. "Reduced Cortical Complexity in Cirrhotic Patients with Minimal Hepatic Encephalopathy." Neural Plasticity 2020 (March 18, 2020): 1–7. http://dx.doi.org/10.1155/2020/7364649.
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Purpose. Gray matter volume loss, regional cortical thinning, and local gyrification index alteration have been documented in minimal hepatic encephalopathy (MHE). Fractal dimension (FD), another morphological parameter, has been widely used to describe structural complexity alterations in neurological or psychiatric disease. Here, we conducted the first study to investigate FD alterations in MHE. Methods and Materials. We performed high-resolution structural magnetic resonance imaging on cirrhotic patients with MHE (n=20) and healthy controls (n=21). We evaluated their cognitive performance using the psychometric hepatic encephalopathy score (PHES). The regional FD value was calculated by Computational Anatomy Toolbox (CAT12) and compared between groups. We further estimated the association between patients’ cognitive performance and FD values. Results. MHE patients presented significantly decreased FD values in the left precuneus, left supramarginal gyrus, right caudal anterior cingulate cortex, right isthmus cingulate cortex, right insula, bilateral pericalcarine cortex, and bilateral paracentral cortex compared to normal controls. In addition, the FD values in the right isthmus cingulate cortex and right insula were shown to be positively correlated with patients’ cognitive performance. Conclusion. Aberrant cortical complexity is an additional characteristic of MHE, and FD analysis may provide novel insight into the neurobiological basis of cognitive dysfunction in MHE.
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Low, Jean M. "Differences in Cognitive Complexity of Adolescents with Foreclosed and Achieved Identity Status." Psychological Reports 85, no. 3_suppl (December 1999): 1093–99. http://dx.doi.org/10.2466/pr0.1999.85.3f.1093.
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The purpose of this study was to assess whether the complexity of the self-concept differs based on identity status in late adolescence. Adolescents in the achieved status have a strong sense of identity that has emerged following an intense period of exploration. Adolescents in the foreclosed status also have a strong sense of identity, but they have never been through a period of exploration. It was expected that adolescents in the achieved status would have more complex self-concepts than those in the foreclosed status. 62 university students were classified into the achieved or foreclosed identity status based on their scores on the Extended Version of the Objective Measure of Ego Identity Status–2. They then completed a trait sort to measure the complexity of their self-concepts. Complexity scores were calculated based on the H statistic, an index of dispersion derived from information theory. The results were as expected. Possible structural changes underlying the process of developing identity are presented, and the usefulness of structural self-concept models for studying development of identify is examined.
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Afzal, Farman, Shao Yunfei, Muhammad Sajid, and Fahim Afzal. "Integrated priority decision index for risk assessment in chaos: cost overruns in transport projects." Engineering, Construction and Architectural Management 27, no. 4 (October 24, 2019): 825–49. http://dx.doi.org/10.1108/ecam-02-2019-0079.
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Purpose Cost overrun is inherent to project chaos, which is one of the key drivers of project failure. The purpose of this paper is to explore the critical elements of complexity-risk interdependency for cost-chaos in the construction management domain by utilizing a multi-criteria decision model. Design/methodology/approach A total of 12 complexity and 60 risk attributes are initially identified from the literature and using expert’s judgements. For the development of a structured hierarchy of key complexity and risk drivers, a real-time Delphi process is adopted for recording and evaluating the responses from experts. Afterwards, a pair-wise comparison using analytical network processing is performed to measure complexity-risk interdependencies against cost alternatives. Findings The findings of the integrated priority decision index (IPDI) suggest that uncertainties related to contingency and escalation costs are the main sources of cost overrun in project drift, along with the key elements such as “the use of innovative technology,” “multiple contracts,” “low advance payment,” “change in design,” “unclear specifications” and “the lack of experience” appear to be more significant to chaos in complexity-risk interdependency network. Research limitations/implications This study did not address the uncertainty and vulnerability exit in the judgment process, therefore, this framework can be extended using fuzzy logic to better evaluate the significance of cost-chaos drivers. Practical implications These results may assist the management of cost overrun to avoid chaos in a project. The proposed model can be applied within project risk management practices to make better-informed technical decisions in the early phases of the project life cycle where uncertainty is high. Originality/value This research addresses the importance of cost overruns as a source of project chaos in dynamic systems where projects reach the edge of chaos and progress stops. A new IPDI index contributes toward evaluating the severity of complexity and risk and their interdependencies which create cost-chaos in infrastructure transport projects.
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Hamood, Mounir Taha. "New Decimation-In-Time Fast Hartley Transform Algorithm." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 4 (August 1, 2016): 1654. http://dx.doi.org/10.11591/ijece.v6i4.10469.
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This paper presents a new algorithm for fast calculation of the discrete Hartley transform (DHT) based on decimation-in-time (DIT) approach. The proposed radix-2^2 fast Hartley transform (FHT) DIT algorithm has a regular butterfly structure that provides flexibility of different powers-of-two transform lengths, substantially reducing the arithmetic complexity with simple bit reversing for ordering the output sequence. The algorithm is developed through the three-dimensional linear index map and by integrating two stages of the signal flow graph together into a single butterfly. The algorithm is implemented and its computational complexity has been analysed and compared with the existing FHT algorithms, showing that it is significantly reduce the structural complexity with a better indexing scheme that is suitable for efficient implementation.
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Hamood, Mounir Taha. "New Decimation-In-Time Fast Hartley Transform Algorithm." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 4 (August 1, 2016): 1654. http://dx.doi.org/10.11591/ijece.v6i4.pp1654-1661.
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This paper presents a new algorithm for fast calculation of the discrete Hartley transform (DHT) based on decimation-in-time (DIT) approach. The proposed radix-2^2 fast Hartley transform (FHT) DIT algorithm has a regular butterfly structure that provides flexibility of different powers-of-two transform lengths, substantially reducing the arithmetic complexity with simple bit reversing for ordering the output sequence. The algorithm is developed through the three-dimensional linear index map and by integrating two stages of the signal flow graph together into a single butterfly. The algorithm is implemented and its computational complexity has been analysed and compared with the existing FHT algorithms, showing that it is significantly reduce the structural complexity with a better indexing scheme that is suitable for efficient implementation.
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Frey, Julian, Bettina Joa, Ulrich Schraml, and Barbara Koch. "Same Viewpoint Different Perspectives—A Comparison of Expert Ratings with a TLS Derived Forest Stand Structural Complexity Index." Remote Sensing 11, no. 9 (May 13, 2019): 1137. http://dx.doi.org/10.3390/rs11091137.
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Forests are one of the most important terrestrial ecosystems for the protection of biodiversity, but at the same time they are under heavy production pressures. In many cases, management optimized for timber production leads to a simplification of forest structures, which is associated with species loss. In recent decades, the concept of retention forestry has been implemented in many parts of the world to mitigate this loss, by increasing structure in managed stands. Although this concept is widely adapted, our understanding what forest structure is and how to reliably measure and quantify it is still lacking. Thus, more insights into the assessment of biodiversity-relevant structures are needed, when aiming to implement retention practices in forest management to reach ambitious conservation goals. In this study we compare expert ratings on forest structural richness with a modern light detection and ranging (LiDAR) -based index, based on 52 research sites, where terrestrial laser scanning (TLS) data and 360° photos have been taken. Using an online survey (n = 444) with interactive 360° panoramic image viewers, we sought to investigate expert opinions on forest structure and learn to what degree measures of structure from terrestrial laser scans mirror experts’ estimates. We found that the experts’ ratings have large standard deviance and therefore little agreement. Nevertheless, when averaging the large number of participants, they distinguish stands according to their structural richness significantly. The stand structural complexity index (SSCI) was computed for each site from the LiDAR scan data, and this was shown to reflect some of the variation of expert ratings (p = 0.02). Together with covariates describing participants’ personal background, image properties and terrain variables, we reached a conditional R2 of 0.44 using a linear mixed effect model. The education of the participants had no influence on their ratings, but practical experience showed a clear effect. Because the SSCI and expert opinion align to a significant degree, we conclude that the SSCI is a valuable tool to support forest managers in the selection of retention patches.
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Schruth, David M., Christopher N. Templeton, and Darryl J. Holman. "On reappearance and complexity in musical calling." PLOS ONE 16, no. 12 (December 17, 2021): e0218006. http://dx.doi.org/10.1371/journal.pone.0218006.
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Music is especially valued in human societies, but music-like behavior in the form of song also occurs in a variety of other animal groups including primates. The calling of our primate ancestors may well have evolved into the music of modern humans via multiple selective scenarios. But efforts to uncover these influences have been hindered by the challenge of precisely defining musical behavior in a way that could be more generally applied across species. We propose an acoustic focused reconsideration of “musicality” that could help enable independent inquiry into potential ecological pressures on the evolutionary emergence of such behavior. Using published spectrographic images (n = 832 vocalizations) from the primate vocalization literature, we developed a quantitative formulation that could be used to help recognize signatures of human-like musicality in the acoustic displays of other species. We visually scored each spectrogram along six structural features from human music—tone, interval, transposition, repetition, rhythm, and syllabic variation—and reduced this multivariate assessment into a concise measure of musical patterning, as informed by principal components analysis. The resulting acoustic reappearance diversity index (ARDI) estimates the number of different reappearing syllables within a call type. ARDI is in concordance with traditional measures of bird song complexity yet more readily identifies shorter, more subtly melodic primate vocalizations. We demonstrate the potential utility of this index by using it to corroborate several origins scenarios. When comparing ARDI scores with ecological features, our data suggest that vocalizations with diversely reappearing elements have a pronounced association with both social and environmental factors. Musical calls were moderately associated with wooded habitats and arboreal foraging, providing partial support for the acoustic adaptation hypothesis. But musical calling was most strongly associated with social monogamy, suggestive of selection for constituents of small family-sized groups by neighboring conspecifics. In sum, ARDI helps construe musical behavior along a continuum, accommodates non-human musicality, and enables gradualistic co-evolutionary paths between primate taxa—ranging from the more inhibited locational calls of archaic primates to the more exhibitional displays of modern apes.
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Hendrie, Gilly A., John Coveney, and David N. Cox. "Defining the complexity of childhood obesity and related behaviours within the family environment using structural equation modelling." Public Health Nutrition 15, no. 1 (August 2, 2011): 48–57. http://dx.doi.org/10.1017/s1368980011001832.
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AbstractObjectiveThe present study aimed to define the complexity of the relationships between the family environment, health behaviours and obesity. A conceptual model that quantifies the relationships and interactions between parent factors, family environment, and certain aspects of children's behaviour and weight status is presented.DesignExploratory structural equation modelling was used to quantitatively model the relationships between parent, child and family environmental factors.SettingAdelaide, South Australia.SubjectsFamilies (n157) with children aged 5–10 years completed self-reported questionnaires, providing data on parents’ knowledge, diet quality and activity habits; child feeding and general parenting styles; and the food and physical activity environments. Outcome variables included children's fruit and vegetable intake, activity and sedentary habits and weight status.ResultsThe proposed model was an acceptable fit (normed fit index = 0·457; comparative fit index = 0·746; root-mean-squared error associated = 0·044). Parents’ BMI (β= 0·32) and nutrition and physical activity knowledge (β= 0·17) had the strongest direct associations with children's BMIZ-score. Parents’ dietary intake and energy expenditure behaviours were indirectly associated with children's behaviour through the creation of the home environment. The physical activity and food environments were associated with children's sedentary (β= −0·44) and activity habits (β= 0·29), and fruit and vegetable intake (β= 0·47), respectively.ConclusionsA conceptual model that quantifies the complex network of family environment factors influencing children's behaviour and weight status is presented. The model provides a basis for future research on larger representative samples with a view to guiding obesity prevention interventions.
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Zhao, Zhonghua, Gangying Hui, Wenzhen Liu, Yanbo Hu, and Gongqiao Zhang. "A Novel Method for Calculating Stand Structural Diversity Based on the Relationship of Adjacent Trees." Forests 13, no. 2 (February 18, 2022): 343. http://dx.doi.org/10.3390/f13020343.
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Understanding the diversity and complexity of stand structure is important for managing the biodiversity of forest ecosystem, and stand structural diversity is essential for evaluating forest management activities. Based on the relationship of adjacent trees, a quantitative method of stand structure diversity is proposed to express the heterogeneity of stand structure in tree species, distribution pattern, species separation and size differentiation. In this study, we defined the diversity of structural unit types and derived a new index of forest structural diversity (SD′) employing the additivity principle of the Shannon–Weiner index. The efficiency of the index was verified by applying the new measure to sixteen field survey samples at different locations. The mountain rainforest in Hainan had the highest forest structural diversity, followed by broad-leaved Korean pine forests in Jiaohe (2), Jiaohe (1) and an oak-broadleaved mixed natural forest at Xiaolongshan (2). The SD′ values of plantations and pure natural forest were lower. The simulated data of different thinning methods and the intensity of broad-leaved Korean pine forests show that the new measure can reflect forest management changes on stand structure diversity. The value of SD′ compared with no treatments and the differences were greater as thinning intensity increased. The SD′ index provides minimum and maximum values for different structural unit types in forests to achieve a unified comparative basis for calculating forest structure diversity. It has the characteristics of the general diversity index and can well express the diversity of tree species, distribution pattern and size differentiation simultaneously. The SD′ index can not only calculate the structural diversity of mixed species forests but can also be used to calculate the structural diversity of pure forests. It can also be used to evaluate the change in stand structure diversity after management interventions.
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Zhang, Fangyuan, and Sibo Wang. "Effective indexing for dynamic structural graph clustering." Proceedings of the VLDB Endowment 15, no. 11 (July 2022): 2908–20. http://dx.doi.org/10.14778/3551793.3551840.
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Graph clustering is a fundamental data mining task that clusters vertices into different groups. The structural graph clustering algorithm ( SCAN ) is a widely used graph clustering algorithm that derives not only clustering results, but also special roles of vertices like hubs and outliers. In this paper, we consider structural graph clustering on dynamic graphs under Jaccard similarity. The state-of-the-art index-based solution focuses on static graphs and incurs prohibitive update costs to maintain indices. Lately, an efficient approximate dynamic structural graph clustering algorithm Dyn-StrClu under Jaccard similarity is proposed. However, their solution needs to fix input parameters while parameter settings of SCAN usually need to be fine-tuned to achieve good clustering results. Motivated by these limitations, we present a study on devising effective index structures for SCAN algorithm on dynamic graphs. Similar to the state-of-the-art dynamic scheme, our main idea to reduce the time complexity is still by bringing approximation to clustering results. However, our solution does not need to fix the input parameters. To achieve this, our solution includes two key components. The first is to maintain a bottom- k sketch for each vertex so that the similarities of affected vertices can be easily updated. The second key is a bucketing strategy that allows us to update clustering results and roles of vertices efficiently. Our theoretical analysis shows that our proposed algorithm achieves O (log n · log M + m / pf ) expected update cost and guarantees to return approximate clustering results with probability 1 - pf after up to M updates. Extensive experiments show that our solution is up to two orders of magnitude faster than the state-of-the-art index-based solution while still achieving high-quality clustering results.
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Asbeck, Thomas, and Julian Frey. "Weak relationships of continuous forest management intensity and remotely sensed stand structural complexity in temperate mountain forests." European Journal of Forest Research 140, no. 3 (February 13, 2021): 721–31. http://dx.doi.org/10.1007/s10342-021-01361-4.
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AbstractUnderstanding the relationship of stand structural complexity and forest management is relevant to create desired stand structures by adapting management strategies under changing disturbance scenarios and climatic conditions. To overcome difficulties in differentiating between strict categories of silvicultural practices and to describe the impact of forest management more appropriate, we used a continuous indicator of forest management intensity (ForMI). The ForMI consists of three components including volumes of natural deadwood, non-native tree species and harvested trees. There are a great number of approaches to quantify stand structure; here we used the recently established stand structural complexity index (SSCI) which represents a density-dependent as well as vertical measure of complexity based on the distribution of points in 3D space inventoried by terrestrial laser scanning. The data collection took place in 135 one-hectare plots managed under close-to-nature forest management (CTNFM) located in the Black Forest, Germany. We build generalized additive models to test the relationship of the SSCI with the ForMI. The model results did not prove a significant relationship between the SSCI and the ForMI, but components of the ForMI showed significant relationships to the SSCI. Our results indicate that the relationship between stand structural complexity and forest management intensity is, while plausible, not trivial to demonstrate. We conclude that forest managers have a relatively wide range of choices in CTNFM to adapt forests within a similar range of management intensity as presented here to future challenges, since management intensity does not change the forest structure drastically.
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McKernan, Stuart, and C. Barry Carter. "Characterization of structural units in tilt grain boundaries." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 120–21. http://dx.doi.org/10.1017/s0424820100121004.
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General tilt grain boundaries can be viewed in terms of small structural units of varying complexity. High-resolution electron microscope (HREM) images of these boundaries in many materials show this repetitive similarity of the atomic structure at the boundary plane. The structure of particular grain boundaries has been examined for several special cases and commonly observed configurations include symmetric tilt grain boundaries and asymmetric tilt grain boundaries with one grain having a prominent, low-index facet. Several different configurations of the boundary structure may possibly occur, even in the same grain boundary. There are thus many possible ways to assemble the basic structural units to form a grain boundary. These structural units and their distribution have traditionally been examined by high-resolution electron microscopy. The images of the projection of the atomic columns (or the tunnels between atomic columns) providing a template for constructing “ball-and-stick ” models of the interface.
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Asok, Anjusha, and Joseph Varghese Kureethara. "The QSPR Study of Butane derivatives: (A Mathematical Approach)." Oriental Journal of Chemistry 34, no. 4 (July 31, 2018): 1842–46. http://dx.doi.org/10.13005/ojc/3404018.
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The QSPR analysis provides a significant structural insight into the physiochemical properties of Butane derivatives. We study some physiochemical properties of fourteen Butane derivatives and develop a QSPR model using four topological indices and Butane derivatives. Here we analyze how closely the topological indices are related to the physiochemical properties of Butane derivatives. For this we compute analytically the topological indices of Butane derivatives and plot the graphs between each of these topological indices to the properties of Butane derivatives using Origin. This QSPR model exhibits a close correlation between Heavy atomic count, Complexity, Hydrogen bond acceptor count, and Surface tension of Butane derivatives with the Redefined first Zagreb index, the Redefined third Zagreb index, the Sum connectivity index and the Reformulated first Zagreb index, respectively.
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YAEGER, LARRY S. "IDENTIFYING NEURAL NETWORK TOPOLOGIES THAT FOSTER DYNAMICAL COMPLEXITY." Advances in Complex Systems 16, no. 02n03 (May 2013): 1350032. http://dx.doi.org/10.1142/s021952591350032x.
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We use an ecosystem simulator capable of evolving arbitrary neural network topologies to explore the relationship between an information theoretic measure of the complexity of neural dynamics and several graph theoretical metrics calculated for the underlying network topologies. Evolutionary trends confirm and extend previous results demonstrating an evolutionary selection for complexity and small-world network properties during periods of behavioral adaptation. The resultant mapping of the space of network topologies occupied by the most complex networks yields new insights into the relationship between network structure and function. The highest complexity networks are found within limited numerical ranges of clustering coefficient, characteristic path length, small-world index, and global efficiency. The widths of these ranges vary from quite narrow to modest, and provide a guide to the most productive regions of the space of neural topologies in which to search for complexity. Our demonstration that evolution selects for complex dynamics and small-world networks helps explain biological evidence for these trends and provides evidence for selection of these characteristics based purely on network function—with no physical constraints on network structure—thus suggesting that functional and structural evolutionary pressures cooperate to produce brains optimized for adaptation to a complex, variable world.
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Liu, Jia-Bao, Qian Zheng, and Sakander Hayat. "The Normalized Laplacians, Degree-Kirchhoff Index, and the Complexity of Möbius Graph of Linear Octagonal-Quadrilateral Networks." Journal of Mathematics 2021 (October 12, 2021): 1–25. http://dx.doi.org/10.1155/2021/2328940.
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The normalized Laplacian plays an indispensable role in exploring the structural properties of irregular graphs. Let L n 8,4 represent a linear octagonal-quadrilateral network. Then, by identifying the opposite lateral edges of L n 8,4 , we get the corresponding Möbius graph M Q n 8,4 . In this paper, starting from the decomposition theorem of polynomials, we infer that the normalized Laplacian spectrum of M Q n 8,4 can be determined by the eigenvalues of two symmetric quasi-triangular matrices ℒ A and ℒ S of order 4 n . Next, owing to the relationship between the two matrix roots and the coefficients mentioned above, we derive the explicit expressions of the degree-Kirchhoff indices and the complexity of M Q n 8,4 .
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Prado, Luis, and Juan Carlos Castilla. "The bioengineer Perumytilus purpuratus (Mollusca: Bivalvia) in central Chile: biodiversity, habitat structural complexity and environmental heterogeneity." Journal of the Marine Biological Association of the United Kingdom 86, no. 2 (March 13, 2006): 417–21. http://dx.doi.org/10.1017/s0025315406013282.
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The mussel Perumytilus purpuratus is distributed from Ecuador to the Strait of Magellan on the Pacific coast; and also extends along the Atlantic coast up to La Lobería, Argentina. The species forms dense three-dimensional matrices which constitute a microhabitat for a wide variety of organisms. Here we test the hypothesis that factors determining habitat structural complexity and environmental heterogeneity of Perumytilus matrices have significant effects on the associated macrofaunal community. In total we found 92 invertebrate taxa in P. purpuratus matrices. The number of layers (stratification) in the matrix had a significant effect on evenness: the greater the stratification, the lower the evenness index. Sediment retention by matrices in sheltered sectors had a significant effect on evenness: greater sediment retention resulted in lower evenness. Sediment retention also determined significant differences in macrofaunal assemblages. In matrices without sediment retention, mussel layering and the presence of algae on the shells of P. purpuratus determined significant macrofaunal differences. As a dominant competitor, P. purpuratus plays a major role in intertidal rocky shores where it is present, structuring communities and determining local biodiversity.
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Ge, Haimiao, Liguo Wang, Haizhu Pan, Yuexia Zhu, Xiaoyu Zhao, and Moqi Liu. "Affinity Propagation Based on Structural Similarity Index and Local Outlier Factor for Hyperspectral Image Clustering." Remote Sensing 14, no. 5 (February 28, 2022): 1195. http://dx.doi.org/10.3390/rs14051195.
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In hyperspectral remote sensing, the clustering technique is an important issue of concern. Affinity propagation is a widely used clustering algorithm. However, the complex structure of the hyperspectral image (HSI) dataset presents challenge for the application of affinity propagation. In this paper, an improved version of affinity propagation based on complex wavelet structural similarity index and local outlier factor is proposed specifically for the HSI dataset. In the proposed algorithm, the complex wavelet structural similarity index is used to calculate the spatial similarity of HSI pixels. Meanwhile, the calculation strategy of the spatial similarity is simplified to reduce the computational complexity. The spatial similarity and the traditional spectral similarity of the HSI pixels jointly constitute the similarity matrix of affinity propagation. Furthermore, the local outlier factors are applied as weights to revise the original exemplar preferences of the affinity propagation. Finally, the modified similarity matrix and exemplar preferences are applied, and the clustering index is obtained by the traditional affinity propagation. Extensive experiments were conducted on three HSI datasets, and the results demonstrate that the proposed method can improve the performance of the traditional affinity propagation and provide competitive clustering results among the competitors.
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Anari, Vahid, Farbod Razzazi, and Rasoul Amirfattahi. "A Sparse Analysis-Based Single Image Super-Resolution." Computers 8, no. 2 (May 27, 2019): 41. http://dx.doi.org/10.3390/computers8020041.
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In the current study, we were inspired by sparse analysis signal representation theory to propose a novel single-image super-resolution method termed “sparse analysis-based super resolution” (SASR). This study presents and demonstrates mapping between low and high resolution images using a coupled sparse analysis operator learning method to reconstruct high resolution (HR) images. We further show that the proposed method selects more informative high and low resolution (LR) learning patches based on image texture complexity to train high and low resolution operators more efficiently. The coupled high and low resolution operators are used for high resolution image reconstruction at a low computational complexity cost. The experimental results for quantitative criteria peak signal to noise ratio (PSNR), root mean square error (RMSE), structural similarity index (SSIM) and elapsed time, human observation as a qualitative measure, and computational complexity verify the improvements offered by the proposed SASR algorithm.
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Wang, Shuangjing, Yujie Wang, Xu Li, Lipeng Liu, Hai Xing, and Yunpei Zhang. "Big Data-Based Boring Indexes and Their Application during TBM Tunneling." Advances in Civil Engineering 2021 (September 24, 2021): 1–18. http://dx.doi.org/10.1155/2021/2621931.
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Tunnel boring machine (TBM) tunneling data have been extensively collected to utilize TBM information technology by analyzing and mining the data for achieving a safe and efficient TBM tunneling. Feature extraction of big data could reduce the complexity for problems, but conventional indexes based on feature extraction, such as field penetration index (FPI), specific penetration (SP), and boreability index (BI), have some disadvantages. Thus, we present novel boring indexes derived from tunneling data in the Yinchao TBM project. Linear thrust-penetration and torque-penetration relationships in filtered ascending sections ( p ≥ 2 mm/r) are proposed using statistical features and through physical mechanism analysis of parameters in the TBM cyclic tunneling process. Boring indexes, such as normal boring difficulty index, initial rock mass fragmentation difficulty index, and tangential boring difficulty index, are defined using the coefficients of the linear thrust-penetration and torque-penetration relationships. Subsequently, the defined boring indexes are verified using performance prediction of 291 cyclic tunneling processes. Finally, a preliminary application of support measure suggestions is conducted using the statistical features of boring indexes, where certain criteria are proposed and verified. The results showed that the criterion of boring indexes for support measure suggestions could achieve a reasonable confirmation, potentially providing quantitative quotas for support measure suggestions in the subsequent construction process.
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Wang, Gang, Dongsheng Guan, Qiuping Zhang, Mervin Richard Peart, Xiao Ling, Yujuan Chen, and Zhu Yuanwei. "Assessment of Changes in Agroecosystem Health in Guangzhou, China." Journal of Environmental Science and Management 22, no. 1 (September 25, 2019): 20–35. http://dx.doi.org/10.47125/jesam/2019_1/03.
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Agroecosystem health refers to the extent to which a healthy agroecosystem can meet socioeconomic and biophysical needs of all residents over time. According to the attempts at assessing agroecosystem health, agroecosystem health depends on both functional and structural characteristics at regional level. However, both functional and structural characteristics have been altered from their natural state by industrialization and urbanization. Thus, this study reports a system-based assessment index to evaluate the health statue of agroecosystem in Guangzhou, South China. Agroecosystem health index (AHI) of Guangzhou decreased from 0.78 in 2000 to 0.71 in 2010. It indicated that this agroecosystem was at relatively healthy state. However, functions of both cultural service and economic sustainable development were not successful as they represented ‘worst’ and ‘sub-healthy’, respectively. With the decreased values between 0.7 and 0.9, the other indices also revealed the need for caution. Particularly, both habitat structure index and provisioning service index exhibited well defined declines during this study period. This study suggests that AHI can be potentially employed to monitor the temporal change in agroecosystem health status, although AHI has some certain limitations and needs further improvement for the complexity of agroecosystems.
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Hickey, Laura J., Jeff Atkins, Robert T. Fahey, Mark T. Kreider, Shea B. Wales, and Christopher M. Gough. "Contrasting Development of Canopy Structure and Primary Production in Planted and Naturally Regenerated Red Pine Forests." Forests 10, no. 7 (July 8, 2019): 566. http://dx.doi.org/10.3390/f10070566.
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Globally, planted forests are rapidly replacing naturally regenerated stands but the implications for canopy structure, carbon (C) storage, and the linkages between the two are unclear. We investigated the successional dynamics, interlinkages and mechanistic relationships between wood net primary production (NPPw) and canopy structure in planted and naturally regenerated red pine (Pinus resinosa Sol. ex Aiton) stands spanning ≥ 45 years of development. We focused our canopy structural analysis on leaf area index (LAI) and a spatially integrative, terrestrial LiDAR-based complexity measure, canopy rugosity, which is positively correlated with NPPw in several naturally regenerated forests, but which has not been investigated in planted stands. We estimated stand NPPw using a dendrochronological approach and examined whether canopy rugosity relates to light absorption and light–use efficiency. We found that canopy rugosity increased similarly with age in planted and naturally regenerated stands, despite differences in other structural features including LAI and stem density. However, the relationship between canopy rugosity and NPPw was negative in planted and not significant in naturally regenerated stands, indicating structural complexity is not a globally positive driver of NPPw. Underlying the negative NPPw-canopy rugosity relationship in planted stands was a corresponding decline in light-use efficiency, which peaked in the youngest, densely stocked stand with high LAI and low structural complexity. Even with significant differences in the developmental trajectories of canopy structure, NPPw, and light use, planted and naturally regenerated stands stored similar amounts of C in wood over a 45-year period. We conclude that widespread increases in planted forests are likely to affect age-related patterns in canopy structure and NPPw, but planted and naturally regenerated forests may function as comparable long-term C sinks via different structural and mechanistic pathways.
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Yalamova, Rossitsa. "Traders Network before Market Crashes." International Journal of Economics and Statistics 9 (December 31, 2021): 128–30. http://dx.doi.org/10.46300/9103.2021.9.19.
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The goal is to reveal scale-dependent topology of the network structure of stock market participants. The correlation structure of stock price series reveals the correlation network between traders. The partition decoupling method reveals the topological structure. The relation of the structural organization to dynamical complexity involves synchronization of trading that may lead to crashes. Log-periodic oscillations of index prices as precursory patterns of crashes are hypothesized to appear as a result of information cascade and herding among traders.
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Yalamova, Rossitsa. "Traders Network before Market Crashes." International Journal of Economics and Statistics 10 (January 25, 2022): 13–15. http://dx.doi.org/10.46300/9103.2022.10.2.
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The goal is to reveal scale-dependent topology of the network structure of stock market participants. The correlation structure of stock price series reveals the correlation network between traders. The partition decoupling method reveals the topological structure. The relation of the structural organization to dynamical complexity involves synchronization of trading that may lead to crashes. Log-periodic oscillations of index prices as precursory patterns of crashes are hypothesized to appear as a result of information cascade and herding among traders.
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Bovshik, A. S. "Dostoevsky on Twitter: Twitterfiction as a Learning Tool in SLA." Язык и текст 7, no. 1 (2020): 99–100. http://dx.doi.org/10.17759/langt.2020070109.
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The article examines the benefits of twitterfiction, a relatively new form of literary production, as a means of second language acquisition in the context of recreational reading. Pushed forward by the influential American educational researcher Stephen Krashen, free voluntary reading (FVR) has been proven to be an extremely powerful factor in developing various aspects of second language competence and getting students committed to reading more. This paper attempts to evaluate both quantitative and qualitative complexity measures of twitterfiction as in the case of TWITTERATURE by Alexander Aciman and Emmett Rensin to better understand the educational potential of the above type of prose. Readability formulas such as the Gunning Fog index and the Coleman-Liau index are deployed to evaluate the structural complexity of the text. ‘Attentive reading’, being a subjective factor in many ways, is a tool we apply to assess the text on the levels of semantics and pragmatics. The research concludes that twitterfiction, as demonstrated in the book, is an adequate ESL supplementary material alongside comics, graphic novels and level 4 graded readers.
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Asgarnezhad, Razieh, Safaa Saad Abdull Majeed, Zainab Aqeel Abbas, and Sarah Sinan Salman. "Providing an Efficient Method to Identify Structural Balanced Social Network Charts using Data Mining Techniques." Wasit Journal of Computer and Mathematics Science 1, no. 1 (April 1, 2022): 49–59. http://dx.doi.org/10.31185/wjcm.vol1.iss1.22.
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As social communications become widespread, social networks are expanding day by day, and the number of members is increasing. In this regard, one of the most important issues on social networks is the prediction of the link or the friend's suggestion, which is usually done using similarities among users. In the meantime, clustering methods are very popular, but because of the high convergence velocity dimensions, clustering methods are usually low. In this research, using spectral clustering and diminishing dimensions, reducing the amount of information, reduces clustering time and reduces computational complexity and memory. In this regard, the spectroscopic clustering method, using a balanced index, determines the number of optimal clusters, and then performs clustering on the normal values of the normalized Laplace matrix. First, the clusters are divided into two parts and computed for each cluster of the harmonic distribution index. Each cluster whose index value for it is greater than 1 will be redistributed to two other clusters, and this will continue until the cluster has an index of less than 1. Finally, the similarity between the users within the cluster and between the clusters is calculated and the most similar people are introduced together. The best results for the Opinions, Google+ and Twitter data sets are 95.95, 86.44 and 95.45, respectively. The computational results of the proposed method and comparison with previous valid methods showed the superiority of the proposed approach.