Hasil untuk "Building construction"

赵巍, 韩雅倩, 张华 et al.

In order to investigate the critical snow formation height of the mixed single-aperture nucleator within the artificial snow machine, an industrial microscope was used to observe the microstructure of the snow crystals, measure the critical snow formation height threshold, and analyse the effect of the air-to-water pressure ratio (0.4MPa:0.4MPa, 0.5MPa:0.45MPa, and 0.5MPa:0.4MPa) and the ambient temperatures (-5℃, -10℃, and -15℃) on the critical snow formation height. The results showed that under the working condition of air-water pressure ratio of 0.4MPa:0.4MPa, when the temperatures were -5℃ and -10℃, the threshold of critical snow formation height did not exist, and when the temperature was -15℃, it was able to form snow, and the threshold of critical snow formation height was 50~55cm; when the air-water pressure ratios were 0.5MPa:0.45MPa, 0.5MPa:0.4MPa, the three ambient temperatures can form snow. And the gas-water pressure ratio and ambient temperature will have a certain effect on the critical snow height, under the same ambient temperature, the larger the gas-water pressure ratio, the smaller the critical snow height; The critical snow formation height increases as the ambient temperature increases from -15°C to -5°C while keeping the air-water pressure ratio constant. When the gas-water pressure ratio is 0.5MPa:0.45MPa, the trend of critical snow formation height with temperature is larger, and the temperature has a greater impact on the critical snow formation height. The results of the study can provide a basis for the design of the optimized arrangement between the nucleator and the nozzle of the snow-making machine.

Mohammed Saleh Alshaikh

The performance of Organic Solar Cells (OSCs) is intrinsically linked to the molecular, electronic, and structural properties of donor and acceptor materials. This study employs various machine learning techniques, namely the Generalized Regression Neural Network (GRNN), Support Vector Machine (SVM), and Tree Boost, to predict key performance metrics of OSCs, including power conversion efficiency (PCE), short-circuit current density (JSC), open-circuit voltage (VOC), and fill factor (FF). The models are trained and evaluated using an experimentally reported dataset compiled by Sahu et al. Correlation analysis demonstrates that material characteristics such as polarizability, bandgap, dipole moment, and charge transfer are statistically associated with OSC performance. The predictive performance of the GRNN model is compared with that of the SVM and Tree Boost models, showing consistently lower prediction errors within the considered dataset. In addition, sensitivity analysis is performed to assess the relative importance of the predictor variables and to examine the influence of kernel functions on GRNN performance. The results indicate that machine learning models, particularly GRNN, can serve as effective data-driven tools for predicting the performance of organic solar cells and for supporting computational screening studies.

Seran Jeon, Myounghoon Lee, Seiyong Kim

We investigated the determinants of awareness, utilization, and satisfaction regarding financial aid programs for single-person households in South Korea and proposed policy enhancements. Our analysis employed logistic regression on microdata from the “2020 Housing Survey” by Statistics Korea, covering the nation and all age groups. We categorized single-person household traits affecting program awareness, utilization, and satisfaction into demographic, socio-economic, housing, and housing perception factors. The dependent variables included awareness, utilization status, and satisfaction levels of government-sponsored financial support programs, which were measured on a four-point Likert scale. The independent variables encompassed demographic, socio-economic, and housing characteristics, which were analyzed comprehensively. We identified factors that influenced awareness, utilization, and satisfaction and recommended tailored policy measures. The findings revealed lower awareness among elderly individuals, women, rural residents, and rental households. Moreover, older age, lower income, rental, and one-room dwelling households exhibited lower utilization rates, with decreased housing and residential environment satisfaction correlating with diminished program satisfaction. Due to the diverse characteristics of single-person households, strategic interventions are crucial. Measures to bridge information gaps, establish comprehensive long-term support systems, and develop differentiated policies tailored to single-person household traits are imperative for improving financial aid programs for this demographic.

Kanat Burak Bozdogan, Erdinc Keskin

In shear wall-frame systems, the foundation rotation that may occur under the shear walls changes the displacements and interstory drift ratios and changes the internal force distribution. This study investigates the effect of foundation rotations under shear walls on internal force distribution in shear-frame systems. The originality of the study lies in considering parabolic loads and dynamic analysis (first mode), in addition to static uniform or triangular distributed loads, when determining the shear wall moment contribution ratio under the influence of foundation rotation. The shear wall contribution ratio, a key parameter in many earthquake codes, is defined as the ratio of the sum of bending moments taken by the shear walls at the base to the overturning moment. It plays a crucial role in determining the building’s behavior. Depending on this ratio, the load-reduction coefficient is changed. This study investigates the effect of foundation rotation on the moment distribution at the base for three different static load cases and the first mode in the dynamic analysis. The multi-story building is modeled as an equivalent sandwich beam. The moment contribution ratio (MCR) was calculated with the help of analytical solutions of the differential equations written for three different load cases in static conditions, and graphs were created for practical use directly calculating the MCR. In the methodology of the study, the initial step involves the calculation of the equivalent sandwich beam stiffness parameters and the foundational rotational spring. Subsequent to these calculations, the MCR values can be directly obtained with the help of graphs. This approach facilitates the rapid and practical determination of the MCR and can be used in the preliminary sizing phase to eliminate possible errors in the data entry of software that performs detailed analysis. In addition, in the presented study, it has been shown that taking a single mode into account is sufficient when calculating MCR values in dynamic analysis.

Chandrawanshi Shrish, Garg Vivek

Rapid urbanization and land scarcity lead to the construction of multiple structures in proximity, supported on common soil media. This proximity increases soil stress, influencing the deformation characteristics of nearby footings. Hence, there is a need to investigate the effect of structure–soil–structure interaction (SSSI) on the footing settlement. In the present study, the effect of SSSI on the footing settlement of a three-storey building is investigated due to the presence of similar adjacent buildings arranged in various patterns (single adjacent building, side-by-side, L-shape, and inverted T-shape). The various interaction analyses are performed using finite element software ANSYS under gravity loading. The vertical and differential settlement of footings obtained from soil–structure interaction (SSI) and SSSI analyses are compared to evaluate the effect of SSSI under various adjacent building arrangements. The results indicate that in SSI case, inner footings show greater settlement compared to peripheral footings which causes high value of differential settlement between peripheral footings and those immediately adjacent to them. However, the presence of an adjacent structure in SSSI cases provides higher settlement in adjacent footings, which in turn reduces the differential settlement in these footings. Moreover, the SSSI effect on vertical settlement in SSSI (L-shaped) and SSSI (inverted T-shaped) is found to be more in corner footing located near to the adjacent buildings due to overlapping of soil stresses from two sides. The study quantifies the extent of settlement increase in various SSSI cases compared to SSI case, contributing valuable insights to mitigating potential settlement issues in densely developed areas.

Chengbin Yuan, Yu Cai, Qiang Gu et al.

Abstract In order to improve the construction technology level of the connection nodes of prefabricated buildings and improve the mechanical properties, fluidity and economy of the connection mortar, this paper adopts the orthogonal experimental design to improve the cement mortar by adding polymer dispersible polymer powder. A modified high-performance mortar with 1d compressive strength of 11Mpa, 3d compressive strength of 19Mpa, 7d compressive strength of 26Mpa, fluidity of 102 mm and final compressive strength higher than M25 was studied. The factors and levels of the orthogonal test are: mortar ratio 1:3,1:4,1:5; silica powder content of 4%,6%,8%; dispersible polymer powder content of 3%,5%,7%. After research, the optimal mixing ratio of modified high-performance mortar is 1:3, the content of silicon powder is 6%, the content of redispersible latex powder is 3%, the content of early strength water reducing agent is 0.1%, and the content of defoamer is 0.5%. The new modified high-performance cement mortar is characterized by short setting time and high early strength, which provides a new idea for the connecting materials of prefabricated buildings, which is of great significance for improving the integrity of prefabricated buildings and the durability of the connection.

Qiuhu Shao, Jingfeng Yuan, Jin Lin et al.

The community and home-based elderly care service system has been proved an effective pattern to mitigate the elderly care dilemma under the background of accelerating aging in China. In particular, the participation of social organizations in community and home-based elderly care service has powerfully fueled the multi-supply of elderly care. As the industry of the elderly care service is in the ascendant, the management lags behind, resulting in the waste of significant social resources. Therefore, performance evaluation is proposed to resolve this problem. However, a systematic framework for evaluating performance of community and home-based elderly care service centers (CECSCs) is absent. To overcome this limitation, the SBM-DEA model is introduced in this paper to evaluate the performance of CECSCs. 186 social organizations in Nanjing were employed as an empirical study to develop the systematic framework for performance evaluation. Through holistic analysis of previous studies and interviews with experts, a systematic framework with 33 indicators of six dimensions (i.e., financial management, hardware facilities, team building, service management, service object and organization construction) was developed. Then, Sensitivity Analysis is used to screen the direction of performance optimization and specific suggestions were put forward for government, industrial associations and CECSCs to implement. The empirical study shows the proposed framework using SBM-DEA and sensitivity analysis is viable for conducting performance evaluation and improvement of CECSCs, which is conducive to the sustainable development of CECSCs.

Sokolov Nikolay

The problem of strengthening weak or overloaded bases is an important objective of underground space development. It is especially urgent if there are alternating weak layers in the base. The paper presents a practical geotechnical case of strengthening the overloaded base of a reinforced concrete foundation plate for a 25-storey residential building under construction. Combined soil piles that consist of Jet (type 1) soil concrete piles reinforced along the longitudinal axis with drilled injection piles made by electric discharge technology (EDT piles) are used as buried structures. This method of arrangement of a combined buried reinforced concrete structure is conditioned by the need to increase the load-bearing capacity of a pile in soil by two or more times.

Davide Simeone

This paper presents the development of a modelling and simulation approach oriented to the prediction of possible re-use phenomena in the field of existing buildings and built heritage. Its scope is to support the complex balancing of conservation and functional requirements. The approach is based on an Agent-Based Modeling approach that includes entities belonging to the three macro areas - building, use process and users – considered.

Alessandro Rigolon, Travis L. Flohr

Although repeated contact with nature helps foster mental and physical health among young people, their contact with nature has been diminishing over the last few decades. Also, low-income and ethnic minority children have even less contact with nature than white middle-income children. In this study, we compared accessibility to play in parks for young people from different income and racial backgrounds in Denver, Colorado. Park access for children and youth was measured using a geographic information system (GIS). Each neighborhood was classified according to income level, residential density, and distance from downtown; and then each park was classified based on formal and informal play, and level of intimacy. Comparisons between neighborhoods show that that low-income neighborhoods have the lowest access and high-income neighborhoods have the highest access to parks, and that differences are even higher for parks with play amenities and high levels of intimacy. To overcome this issue, the paper proposes a framework for action to improve access to parks for low-income children and youth and to help planners, decision makers and advocacy groups prioritize park investments.

G.I. Abdullaev

Influence of organizational and technological factors on management efficiency can be considered on the elements of system of the organization and technology of building. Organizational and technological factors substantially cause level of organizational-technological reliability of building manufacture, and their level, in turn, depends on work quality of a control system. Regulation and management of building on the basis of organizational-technological decisions includes change of technological schemes of execution phase and erection of constructions, redistribution of labor and technical resources, change of sequence of development of particular work fronts, change of methods of work organization. It leads to changes of values of organizational-technological parameters and, hence, change of the sizes of financial expenses. Development of the operating decision should provide minimization of deviation from the size of planned financial expenses and with it to provide the efficiency of operating system. The primary goal of the operating decision is preservation of the basic planned targets at the minimum increase in financial expenses. In the article the calculation of functioning efficiency of the management system against a background of organizational and technological parameters of construction is given. This calculation makes it possible to select the most rational parameters of organization and technology of construction.

Mara Elaine Fonseca Rodrigues

Resumo A presente pesquisa tem como desafio apresentar aos docentes envolvidos no processo educativo-formativo do profissional da informação caminhos alternativos para a formação desse profissional. Apoiada no referencial teórico do paradigma científico emergente propõe-se a investigar as experiências inovadoras adotadas no processo de formação dos profissionais da informação, tendo o ensino com pesquisa como principal indicador para caracterizar essas inovações. Para tanto, utiliza uma abordagem de predominância qualitativa o que possibilita análises mais detalhadas e significativas. Os resultados alcançados evidenciam que os professores, de maneira geral, demonstram preocupação em vincular e articular ensino e pesquisa, reconhecendo a pesquisa como a grande geradora da construção do conhecimento. Pelos depoimentos colhidos pode-se dizer que os professores favorecem a articulação do ensino com a pesquisa, fazem referências às pesquisas que realizam e se utilizam de seus resultados na sua metodologia de ensino.  No entanto, todo esse movimento não chega a representar uma ruptura paradigmática no processo de ensino-aprendizagem nas áreas de Biblioteconomia e Ciência da Informação. Palavras-chave formação profissional e inovação; profissional da informação; articulação ensino-pesquisa Abstract This research faces the challenge of presenting to teachers involved in education-training of information professionals alternative paths for the formation of this professional. Building on the theoretical framework of the emerging scientific paradigm it proposes to investigate the innovative projects adopted in the process of training of information professionals, and teaching with research as the main indicator to characterize such innovations. We also use a predominantly qualitative approach which enables more detailed and meaningful analysis. The results obtained show that teachers in general show concern and interest in linking teaching and research, recognizing research as a major generator of knowledge construction. Testimonies reveal that teachers favor the articulation of education through research, make references to the research they perform and their results are used in their teaching methodology. However, all this movement is not enough to represent a paradigmatic rupture in the process of teaching and learning in the areas of Library and Information Science. Keywords vocational training and innovation; information professionals; linking teaching and research

Žygimantas Blaževičius, Audronis Kazimieras Kvedaras

A certain amount of analytical methods for determining fire resistance of concrete filled steel tubular columns are developed. Mostly those methods refer to or have as an origin the data about the results of real experiments. The research work on this kind of composite column behaviour under fire conditions with a wide range of different parameters measuring was performed. The behaviour of 16 axially loaded HC‐FST (hollow concrete filled steel tubular) columns without fire protection under conditions similar to ISO‐834 fire and under normal conditions was experimentally investigated and the results are presented in this paper. The experimental values of fire resistance were measured and the failure mode was determined for 4 axially loaded columns. And for the comparison of test parameters, 4 axially loaded HC‐FST columns were tested under normal conditions. In addition, 8 hollow concrete‐filled steel tubular stub columns and 4 hollow concrete tubular stub columns under normal conditions were tested. The final objective was to prepare experimental data for analysis and to find some analytical dependence between test parameters with the most significant influence on the fire results of HC‐FST columns. Centriškai gniuždomų hc-fst kolonų atsparumo ugniai eksperimentinis tyrimas Santrauka Yra sukurta keletas analitinių metodų vamzdinių plieno kolonų su betono šerdimi atsparumui kaitros sąlygomis nustatyti. Didžiuma šių analitinių metodų yra paremti arba buvo kuriami analizuojant eksperimentinių kaitrinių tyrimų duomenis. Buvo atlikti vamzdinių plieno kolonų su tuščiavidure betono šerdimi elgsenos kaitros sąlygomis eksperimentiniai tyrimai, matuojant skirtingus bandymo parametrus. Eksperimentiškai ištirta 16-kos centriškai gniuždomų HC-FST (centrifuguotų tuščiavidurių betonšerdžių plieninių vamzdinių) kolonų, nepadengtų apsauginėmis (atsparumą kaitrai didinančiomis) dangomis, elgsena kaitros sąlygomis (panašiomis į ISO-834 standartinį gaisrą), ir tyrimo rezultatai yra pateikti šiame straipsnyje. Nustatytos 4-ių centriškai gniuždomų HC-FST kolonų atsparumo kaitrai eksperimentinės reikšmės ir suirimo pobūdis. Bandymų parametrams palyginti buvo išbandytos 4-ios centriškai gniuždomos HC-FST kolonos normaliomis sąlygomis, taip pat centrišku gniuždymu buvo išbandyti 8 HC-FST trumpi elementai ir 4 betoniniai žiedai normaliomis sąlygomis. Pagrindiniai straipsnyje aprašyto tyrimo tikslai – gauti eksperimentinių duomenų analizei ir priklausomybėms tarp bandymo parametrų, darančių didžiausią įtaką HC-FST kolonų atsparumui kaitrai, išvesti. First Published Online: 14 Oct 2010 Reikšminiai žodžiai: eksperimentinis tyrimas, ašinė apkrova, betonšerdės plieninės vamzdinės kolonos, laikomoji galia, atsparumas ugniai.