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1.
Heliyon ; 10(7): e28410, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560179

RESUMO

Higher entrepreneurial traits significantly increase the likelihood of graduate students venturing into entrepreneurship. This study intended to develop a scale for assessing the entrepreneurial traits of graduate students, recognizing a gap in existing literature and measurement tools predominantly developed for countries with conducive entrepreneurial climates. Aligned with Ajzen's theory of planned behavior, the study employed a modified Delphi method, including prototype development, two Delphi surveys, and subsequent statistical analyses. The robustness of the final items and scale in effectively capturing the entrepreneurial traits of graduate students is supported by descriptive statistical analyses (SD ≤ 1.5, Interquartile Range ≤1, and Level of Agreement ≥70%), content validity analysis (I-CVI≥ 0.8, S-CVI/Ave = 0.92; S-CVI/UA = 0.4), and Kendall's Coefficient of Concordance analysis (X2 (37, N = 30) = 700.504, W = 0.631, p < 0.01). Ultimately, the scale comprises 38 items organized into three overarching thematic areas: life philosophy, creating and utilizing mindset, and supportive and motivating environment. Consistent with existing literature, entrepreneurial traits are intricately linked to individuals' life perspectives, often characterized by a desire for self-autonomy. Additionally, the ability to create or leverage available resources and the presence of a conducive external environment emerge as pivotal dimensions in entrepreneurial traits. Notably, the study highlights the critical influence of a country's environment and policies, mainly through university courses and short-term programs, in shaping the development of entrepreneurial traits.

2.
Bioscience ; 74(3): 146-158, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38560618

RESUMO

What are social niches, and how do they arise and change? Our first goal in the present article is to clarify the concept of an individualized social niche and to distinguish it from related concepts, such as a social environment and a social role. We argue that focal individuals are integral parts of individualized social niches and that social interactions with conspecifics are further core elements of social niches. Our second goal in the present article is to characterize three types of processes-social niche construction, conformance, and choice (social NC3 processes)-that explain how individualized social niches originate and change. Our approach brings together studies of behavior, ecology, and evolution and integrates social niches into the broader concept of an individualized ecological niche. We show how clarifying the concept of a social niche and recognizing the differences between the three social NC3 processes enhance and stimulate empirical research.

3.
Waste Manag Res ; : 734242X241241607, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600740

RESUMO

The residential construction sector in New Zealand and worldwide is experiencing increased criticism for generating substantial waste that poses environmental concerns. Accordingly, researchers have advocated implementing residential construction waste reduction (RCWR) strategies as a sustainable solution to managing construction waste (CW). This article aims to provide a comprehensive overview of RCWR by analysing 87 articles from the Scopus database using bibliometric and critical review methods. The co-occurrence analysis of keywords revealed five clusters, in which five main themes emerged: (i) waste generation and management performance, (ii) prefabrication and life cycle assessment concepts, (iii) design concepts, (iv) circular economy and (v) decision-making concepts. The findings suggest that sustainable practices such as designing for waste reduction, prefabrication, waste quantification, three-dimensional printing and building information modelling can effectively achieve RCWR. The study also highlights the benefits of RCWR, including reducing environmental impacts, and identifies management, economic, legislative, technology and cultural barriers that affect the implementation of RCWR strategies. These results provide valuable insights to support future policy formulation and research direction for RCWR in New Zealand.

4.
Front Plant Sci ; 15: 1351466, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38584949

RESUMO

Genomic prediction (GP) using haplotypes is considered advantageous compared to GP solely reliant on single nucleotide polymorphisms (SNPs), owing to haplotypes' enhanced ability to capture ancestral information and their higher linkage disequilibrium with quantitative trait loci (QTL). Many empirical studies supported the advantages of haplotype-based GP over SNP-based approaches. Nevertheless, the performance of haplotype-based GP can vary significantly depending on multiple factors, including the traits being studied, the genetic structure of the population under investigation, and the particular method employed for haplotype construction. In this study, we compared haplotype and SNP based prediction accuracies in four populations derived from European maize landraces. Populations comprised either doubled haploid lines (DH) derived directly from landraces, or gamete capture lines (GC) derived from crosses of the landraces with an inbred line. For two different landraces, both types of populations were generated, genotyped with 600k SNPs and phenotyped as lines per se for five traits. Our study explores three prediction scenarios: (i) within each of the four populations, (ii) across DH and GC populations from the same landrace, and (iii) across landraces using either DH or GC populations. Three haplotype construction methods were evaluated: 1. fixed-window blocks (FixedHB), 2. LD-based blocks (HaploView), and 3. IBD-based blocks (HaploBlocker). In within population predictions, FixedHB and HaploView methods performed as well as or slightly better than SNPs for all traits. HaploBlocker improved accuracy for certain traits but exhibited inferior performance for others. In prediction across populations, the parameter setting from HaploBlocker which controls the construction of shared haplotypes between populations played a crucial role for obtaining optimal results. When predicting across landraces, accuracies were low for both, SNP and haplotype approaches, but for specific traits substantial improvement was observed with HaploBlocker. This study provides recommendations for optimal haplotype construction and identifies relevant parameters for constructing haplotypes in the context of genomic prediction.

5.
Materials (Basel) ; 17(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38591442

RESUMO

Africa is the third-richest continent in the world in terms of bamboo species. Despite these laudable natural resources, most African countries still use asbestos cement board as one of their major building materials. This is chiefly due to the high cost of equipment and technologies associated with non-asbestos-fiber cement board production. The current research seeks to underscore the possibility of utilizing these massive continent resources for non-asbestos-fiber cement board production by employing the existing production process in the asbestos cement industries via an innovatively developed laboratory-simulated Hatschek process. Non-asbestos-fiber cement boards incorporating kraft and bamboo fibers were successfully produced in the laboratory using this innovative method based on Hatschek technology, with natural fibre addition in the range of 2-6 wt.%. Experimental results revealed that the Flexural strength and deflection of the board improved significantly, producing optimum values of 10.41 MPa and 2.0 mm, respectively for composite board reinforced with 10 wt.% and 6 wt.% of kraft pulp and bamboo fibers, respectively. The SEM morphology of the fractured surfaces revealed the mode of composite fracture as well as good interaction at the fiber-matrix interface. Overall, the mechanical properties of the developed composite boards satisfy the minimum requirements of relevant standards based on fiber cement flat sheets and can be employed for internal building applications in low-cost housing estates in developing countries. The outcome of this research indicates that the current industrial production process based on Hatschek technology can be employed for non-asbestos-fiber cement board production using the studied natural fiber.

6.
MethodsX ; 12: 102675, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38585181

RESUMO

Intravenous self-administration in rats is used widely to study the reinforcing effects of drugs and serves as the gold standard for assessing their use and misuse potential. One challenge that researchers often encounter when scaling up experiments is balancing the cost, time investment to construct, and robustness of each implanted catheter. These catheters include multiple components such as surgical meshing and a variety of entry ports designed to facilitate the connection of the rat to a catheter port tethering system. Other considerations include maintaining the catheters free of blockage during the extent of the drug self-administration experiment. These large-scale studies provide ample opportunity for the catheter system to fail. The failure and replacement of commercially purchased catheters leads to ballooning expenses, and the failure of in-lab manufactured catheters requires the manufacture of reserves, also increasing costs, as these handmade products are inherently more variable. We have developed a catheter system that combines a commercially available implantable back-mounted entry connector system with inexpensive medical items such as surgical mesh, sutures, and an air-tight back flow prevention system to bolster the overall success of self-administration experiments.•Method to bolster commercially available jugular catheter components for long-lasting self-administration experiments.•Reduces the overall cost per unit of self-administration experiments.•Easily assembled by laboratory students and staff.

7.
J Child Lang ; : 1-34, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38646693

RESUMO

Many studies have explored children's acquisition of temporal adverbs. However, the extent to which children's early temporal language has discursive instead of solely temporal meanings has been largely ignored. We report two corpus-based studies that investigated temporal adverbs in Finnish child-parent interaction between the children's ages of 1;7 and 4;11. Study 1 shows that the two corpus children used temporal adverbs to construe both temporal and discursive meanings from their early adverb production and that the children's usage syntactically broadly reflected the input received. Study 2 shows that the discursive uses of adverbs appeared to be learned from contextually anchored caregiver constructions that convey discourse functions like urging and reassuring, and that the usage is related to the children's and caregivers' interactional roles. Our study adds to the literature on the acquisition of temporal adverbs by demonstrating that these items are learned also with additional discursive meanings in family interaction.

8.
Huan Jing Ke Xue ; 45(5): 2828-2839, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629545

RESUMO

It is of great practical significance for regional sustainable development and ecological construction to quantitatively analyze the impact of construction land expansion on terrestrial ecosystem carbon storage and to explore the optimization scheme of simulating construction land expansion to improve future ecosystem carbon storage. Based on the land use and cover change (LUCC) and other geospatial data of the Beijing-Tianjin-Hebei Urban Agglomeration from 2000 to 2020, this study utilized the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model and the patch-generating land-use simulation (PLUS) model to assess and analyze the changes in ecosystem carbon stocks and spatial patterns regionally. In this study, we performed linear regression analysis to investigate the relationship between urban land expansion and changes in ecosystem carbon stocks for varying urban land proportion levels during two distinct time intervals, 2000-2010 and 2010-2020, which was conducted at a spatial resolution of 2 km. Three distinct urban land expansion scenarios were subjected to simulation to forecast the prospective land use pattern by 2030. Subsequently, we quantified the ramifications of these scenarios on ecosystem carbon stocks during the period from 2020 to 2030. The results were as follows:① In the Beijing-Tianjin-Hebei Urban Agglomeration, the ecosystem carbon stocks exhibited notable variations over the study period, with values of 2 088.02, 2 106.78, and 2 121.25 Tg recorded for the years 2000, 2010, and 2020, respectively, resulting in a cumulative carbon sequestration of 33.23 Tg C during the study duration. It is noteworthy that forest carbon storage emerged as the dominant contributor, with an increase from 1 010.17 Tg in 2000 to 1 136.53 Tg in 2020. Throughout the study period, the spatial distribution of carbon stocks displayed relative stability. Regions characterized by lower carbon content were concentrated in the vicinity of the Bohai Rim region and in proximity to cities such as Beijing, Tianjin, and Shijiazhuang, as well as rural settlements. In contrast, grid units with moderate and high carbon stocks were predominantly situated in the western Taihang Mountain and the northern Yanshan Mountain. Additionally, there was a tendency of increasing carbon stocks in the Taihang Mountain and Yanshan Mountain region, whereas those surrounding major urban centers such as Beijing, Tianjin, Shijiazhuang, and Tangshan experienced a notable decline in carbon stocks. Such reductions were most pronounced in regions undergoing urban land expansion during the study period. ② In grid units with an urban land proportion exceeding 10% at each level, a strong correlation was observed between urban land expansion and changes in carbon stocks during both the 2000-2010 and 2010-2020 periods. The changes in urban land proportion adequately explained the variations in carbon stocks. However, the explanatory power of urban land on carbon stocks decreased during the 2010-2020 period, indicating that other factors played a more substantial role in influencing carbon stocks during this time. The regression coefficients for both periods exhibited a fluctuating upward trend. In comparison to that during the 2000-2010 period, the impact of urban land expansion on carbon stocks was relatively smaller during 2010-2020, indicating a weakening influence. ③ In light of three distinct development scenarios, namely natural development (Scenario Ⅰ), a 15% reduction in the rate of urban land expansion (Scenario Ⅱ), and a 30% reduction in the rate of urban land expansion (Scenario Ⅲ), the projected ecosystem carbon stocks for the Beijing-Tianjin-Hebei Urban Agglomeration in the year 2030 were estimated to be 2 129.12, 2 133.55, and 2 139.10 Tg, respectively. These projections indicated an increase of 7.88, 12.30, and 17.85 Tg in comparison to the current carbon stocks. All scenarios demonstrated that the terrestrial ecosystem would play a role of carbon sink, particularly with the greatest carbon sink observed in the scenario with a 30% reduction in urban land expansion. The fit performance between urban land expansion and carbon stock changes during the 2020-2030 period was significantly better than that during the 2000-2010 and 2010-2020 periods, and the regression coefficients showed a fluctuating increase with an increase in urban land proportion. Across grid units with different urban land proportion levels, the regression coefficients exhibited the order of Scenario Ⅰ < Scenario Ⅱ < Scenario Ⅲ. In pursuit of the carbon peaking and carbon neutrality goals, the Beijing-Tianjin-Hebei Urban Agglomeration should prioritize scenarios with reduced rates of urban land expansion, especially in regions with higher urban land proportions.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38630406

RESUMO

The in-depth implementation of the "Broadband China Strategy" is of great significance in promoting the synergistic governance of urban carbon reduction and pollution reduction. In this paper, based on the "Broadband China" pilot program implemented in China in 2014 as a quasi-natural experiment, the coupled synergy model is used to measure the carbon and pollution reduction synergy index based on the balanced panel data of 277 prefectural-level cities and above in China from 2006 to 2020, and the staggered and synthetic DID methods are applied to investigate the impact of the Broadband China strategy on carbon and pollution reduction synergy and its mechanism. strategy on carbon and pollution reduction synergy and its mechanism. The conclusions of the study show that (1) the Broadband China strategy significantly improves the synergistic governance of carbon reduction and pollution reduction. (2) The mechanism results show that Broadband China mainly realizes carbon and pollution synergistic governance by promoting source control and process innovation but does not have an effective mediating role in end-of-pipe treatment. (3) The results of heterogeneity analysis show that Broadband China weakens the traditional geographic advantage, narrows the carbon pollution synergistic governance gap at the national and regional levels, and significantly improves the regional carbon reduction and pollution reduction governance level. This paper examines the micro-mechanism of the Broadband China strategy on carbon pollution synergistic governance from the whole process of production activities, which provides a new perspective for the study of carbon pollution synergistic governance, and provides an empirical basis for carbon pollution synergistic governance in China.

10.
Artigo em Chinês | MEDLINE | ID: mdl-38604691

RESUMO

With the deepening reform of ideological and political education, Medical Parasitology teaching needs to update the teaching concept, change the teaching ideas, as well as keep trying to combine ideological and political education with the curriculum content closely. In addition to teaching students' basic knowledge and practical skills, teachers are needed to cultivate their moral literacy and political awareness through course teaching, so as to provide the basis for students' subsequent adaptations to social environments and jobs. Currently, the study of ideological and political education in Medical Parasitology teaching is still in the exploratory stage. Therefore, colleges and universities need to carry out effective construction of ideological and political education in Medical Parasitology teaching, in order to achieve good teaching outcomes and provide insights into ideological and political education in teaching.


Assuntos
Educação Médica , Estudantes , Humanos , Escolaridade , Currículo , Universidades
11.
Biotechnol J ; 19(4): e2400114, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622790

RESUMO

Molecular cloning facilitates the assembly of heterologous DNA fragments with vectors, resulting in the generation of plasmids that can steadily replicate in host cells. To efficiently and accurately screen out the expected plasmid candidates, various methods, such as blue-white screening, have been developed for visualization. However, these methods typically require additional genetic manipulations and costs. To simplify the process of visualized molecular cloning, here we report Rainbow Screening, a method that combines Gibson Assembly with chromoproteins to distinguish Escherichia coli (E. coli) colonies by naked eyes, eliminating the need for additional genetic manipulations or costs. To illustrate the design, we select both E. coli 16s rRNA and sfGFP expression module as two inserted fragments. Using Rainbow Screening, false positive colonies can be easily distinguished on LB-agar plates. Moreover, both the assembly efficiency and the construct accuracy can exceed 80%. We anticipate that Rainbow Screening will enrich the molecular cloning methodology and expand the application of chromoproteins in biotechnology and synthetic biology.


Assuntos
DNA , Escherichia coli , Escherichia coli/genética , RNA Ribossômico 16S , Clonagem Molecular , Plasmídeos , DNA/genética , Vetores Genéticos
13.
Front Glob Womens Health ; 5: 1352793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567108

RESUMO

Introduction: Most research on Intimate Partner Violence (IPV) focuses on the physical, sexual and psychological abuse, with less focus on the financial abuse. This study explores nursing mothers' experiences and perceptions of financial and material support from their significant others and traditional birth attendants' (TBA) observations of support to nursing mothers in their communities. Methods: Using purposive sampling, focus groups and interviews were conducted primarily in Ewe language among nursing mothers and TBAs in rural communities in Hohoe, Volta region, Ghana. All discussions were audio-recorded and transcribed for analysis. Thematic analysis guided by the social constructivist framework was used in data analysis. Results: Twenty-seven women participated in the study, ranging in ages from 19 to 82 (20 nursing mothers; 7 TBAs). Most participants were married (19) and about 65% reported working outside the home (10 nursing mothers; 7 TBAs). Two themes emerged from the data analysis: Lack of support from partners for housekeeping chores and finances; and TBAs as mediators. Nursing mothers who reported lack of financial support did not perceive it as abuse, rather as hinderance to their efforts to care for their children. TBAs act as mediators interceding on behalf of nursing mothers with their husbands and fathers of their children, while also seeking resources to support them. Discussion: Understanding the perceptions and socio-cultural meanings women attached to IPV experience is essential for effective intervention to reduce IPV. In addition, TBAs can be a resource in intervening to alleviate IPV in their communities, thereby improving maternal and child health.

14.
Front Plant Sci ; 15: 1371222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567138

RESUMO

Pan-genome studies are important for understanding plant evolution and guiding the breeding of crops by containing all genomic diversity of a certain species. Three short-read-based strategies for plant pan-genome construction include iterative individual, iteration pooling, and map-to-pan. Their performance is very different under various conditions, while comprehensive evaluations have yet to be conducted nowadays. Here, we evaluate the performance of these three pan-genome construction strategies for plants under different sequencing depths and sample sizes. Also, we indicate the influence of length and repeat content percentage of novel sequences on three pan-genome construction strategies. Besides, we compare the computational resource consumption among the three strategies. Our findings indicate that map-to-pan has the greatest recall but the lowest precision. In contrast, both two iterative strategies have superior precision but lower recall. Factors of sample numbers, novel sequence length, and the percentage of novel sequences' repeat content adversely affect the performance of all three strategies. Increased sequencing depth improves map-to-pan's performance, while not affecting the other two iterative strategies. For computational resource consumption, map-to-pan demands considerably more than the other two iterative strategies. Overall, the iterative strategy, especially the iterative pooling strategy, is optimal when the sequencing depth is less than 20X. Map-to-pan is preferable when the sequencing depth exceeds 20X despite its higher computational resource consumption.

15.
Sci Rep ; 14(1): 7890, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570561

RESUMO

This research aims to elucidate the relationship between circular design strategies (CDS) and the economic sustainability of construction projects (ESCP), examining the mediating role of organizational culture (OC). Motivated by the imperative to develop a sustainable circular economy (CE) model in the building industry, our study focuses on a crucial dimension of CE processes. Specifically, we investigate how construction firms' organizational values shape their pursuit of desired economic outcomes within CE theory. Through a comprehensive analysis of 359 responses from a cross-sectional survey of Chinese construction firms employing Partial Least Squares-Structural Equation Modeling (PLS-SEM), our findings reveal a positive albeit weakly impactful association between CDS and ESCP. Simultaneously, OC is identified as a factor detrimental to ESCP. Notably, this study unveils the influential roles of hierarchical culture (HC) and group culture (GC) in shaping the current state of ESCP in China. Emphasizing the significance of CDS, we propose that contract administrators proactively reposition their organizations to adopt strategies conducive to achieving the necessary economic output for construction projects. The originality aspect lies in this research contributes to the existing body of knowledge by offering empirical insights into the theoretical framework, marking the first such empirical study in northern China. We conclude by critically examining research outcomes and limitations while providing insightful recommendations for future research to foster sustainable construction practices in the Chinese context.

16.
Heliyon ; 10(7): e28744, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38576582

RESUMO

This study takes Shanghai's restaurants as a case study of urban soft infrastructure, employing big data sets from third-party website platforms for multi-source data fusion, to deeply analyze the impact of urban land expansion and population dynamics on the availability, affordability, acceptability, and accessibility of restaurants. The case study reveals that, despite the Shanghai municipal authorities' focus on mitigating overcrowding in the central urban areas, soft infrastructure such as restaurants in new urban districts remains at a relative disadvantage. The decentralization of soft infrastructure to peripheral urban areas has not met policy expectations, presenting a spatial imbalance characterized by greater provision in the main urban areas than in new urban districts, and higher in Puxi than in Pudong. The single-threshold model uncovers that the positive impact of land urbanization and population dynamics on restaurant convenience undergoes a transformation after reaching a certain critical point, where the linear relationship and synchronous growth shift. By controlling the development area of construction land and the population density within regions, a dynamic combination of availability, affordability, acceptability, and accessibility of restaurants can be achieved. This forms a spatio-temporal management strategy that integrates land, population, and comfort facilities, potentially alleviating the inequity of comfort facilities in Shanghai and the central urban areas' siphoning effect.

17.
Work ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38578911

RESUMO

Background: The body of literature regarding the use of an upper limb exoskeleton during authentic working conditions is sparse. Objective: The aim of this study was to evaluate the effectiveness of an upper limb exoskeleton in reducing muscle strain during authentic industrial construction work. Methods: Fifteen male participants, comprising of roofers, scaffolders, builders, bricklayers, and graders performing overhead work participated in the study. During work without (REF) and with exoskeleton (EXO), muscle activity from 8 muscles, heart rate (HR), metabolic equivalent (MET), and upper arm elevation angles were recorded. Results: When using the exoskeleton, a significant reduction of 20.2% in average muscle activity of 8 muscles was found. The largest effect focused on m. deltoideus, where 46.2 and 32.2% reduction occurred in medial and anterior parts of the muscle, respectively. HR and MET were unaffected. Upper arm elevation angles were similar between REF and EXO, indicating equal biomechanical loading. Conclusions: This study indicates that exoskeletons show great promise in reducing the potential for musculoskeletal strain during authentic overhead construction work.

18.
J Relig Health ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581542

RESUMO

The purpose of the study was to construct and validate a Belief in Divine Retribution Scale for the Pakistani Muslim population. The process of construction and validation was completed by following standardized guidelines for scale construction (Boateng et al., 2018). The present study was carried out in four phases. In phase I, the task of item generation was completed through literature review and interviews (inductive and deductive approaches). Phase II aimed at exploration of factor structure. Exploratory factor analysis was carried out on a sample of seven hundred Muslim participants. Data for EFA were collected through a purposive sampling technique, which comprised both men (n = 339) and women (n = 361) with an age range of 18 to 69 years. Results of EFA revealed a two-factor structure with a cumulative variance of 42.59 and with a Cronbach alpha reliability of .83. To confirm the obtained factor structure, Phase III was carried out on a sample of three hundred Muslim participants. The results of CFA confirmed the two-dimensional factor structure with a good model fit to the data. Phase IV provided evidence of convergent and discriminant validity of the scale. Moreover, data for validation were collected from an independent sample (N = 204). Finally, the results of validation revealed that there exists a significant positive correlation of Belief in Divine Retribution Scale with Belief in Just World Scale, which provided evidence of convergent validity. However, there exists a non-significant correlation of Belief in Divine Retribution Scale with Religious Practice Subscale of Short Muslim Practice and Belief Scale, and it provided evidence of discriminant validity. Implications along with limitations and suggestions for future research have also been mentioned.

19.
Sci Total Environ ; 927: 172312, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38599403

RESUMO

The surge in urban development has resulted in a substantial accumulation of construction solid waste (CSW). However, prevailing identification methods of CSW remain predominantly two-dimensional in scope and need to be more efficient. This study employs an approach, combining simulation and experimental analyses, to delve into the factors influencing the electromagnetic scattering characteristics of CSW, investigating the feasibility of employing Synthetic Aperture Radar (SAR) to recognize CSW. The findings show that the computational time of MLFMM and PO is only 3.28 % and 0.029 % of MM among different simulation methods. The results underscore the collective impact of material types, surface structures, and curvature on the scattering characteristics of CSW. The difference in average intensity between different materials can reach up to 13 dB. Exploiting these distinctions in scattering enables the precise identification of high-value waste components, such as intact bricks and steel bars, within the intricate landscape of CSW.

20.
Sci Rep ; 14(1): 8381, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600161

RESUMO

Preplaced aggregate concrete (PAC) also known as two-stage concrete (TSC) is widely used in construction engineering for various applications. To produce PAC, a mixture of Portland cement, sand, and admixtures is injected into a mold subsequent to the deposition of coarse aggregate. This process complicates the prediction of compressive strength (CS), demanding thorough investigation. Consequently, the emphasis of this study is on enhancing the comprehension of PAC compressive strength using machine learning models. Thirteen models are evaluated with 261 data points and eleven input variables. The result depicts that xgboost demonstrates exceptional accuracy with a correlation coefficient of 0.9791 and a normalized coefficient of determination (R2) of 0.9583. Moreover, Gradient boosting (GB) and Cat boost (CB) also perform well due to its robust performance. In addition, Adaboost, Voting regressor, and Random forest yield precise predictions with low mean absolute error (MAE) and root mean square error (RMSE) values. The sensitivity analysis (SA) reveals the significant impact of key input parameters on overall model sensitivity. Notably, gravel takes the lead with a substantial 44.7% contribution, followed by sand at 19.5%, cement at 15.6%, and Fly ash and GGBS at 5.9% and 5.1%, respectively. The best fit model i.e., XG-Boost model, was employed for SHAP analysis to assess the relative importance of contributing attributes and optimize input variables. The SHAP analysis unveiled the water-to-binder (W/B) ratio, superplasticizer, and gravel as the most significant factors influencing the CS of PAC. Furthermore, graphical user interface (GUI) have been developed for practical applications in predicting concrete strength. This simplifies the process and offers a valuable tool for leveraging the model's potential in the field of civil engineering. This comprehensive evaluation provides valuable insights to researchers and practitioners, empowering them to make informed choices in predicting PAC compressive strength in construction projects. By enhancing the reliability and applicability of predictive models, this study contributes to the field of preplaced aggregate concrete strength prediction.

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