The increasing demand for sustainable cooling technologies and the shift away from fossil fuels have heightened interest in solar-assisted thermal systems, particularly for powering absorption refrigeration units in hot environments. This study evaluated the performance of a closed-loop solar water heating system used to supply hot water to an absorption refrigeration machine. The analysis was carried out using the utilizability (f-chart) method and the MATHLAP computer program. The study considered various operating conditions and four types of flat-plate solar collectors: Type A: Single transparent cover solar collector with absorbent surface painted in standard black color; Type B: Single transparent cover solar collector with absorbent surface coated in black selective material; Type C: Solar collector with two transparent covers with absorbent surface painted in standard black color; and Type D: Solar collector with two transparent covers with absorbent surface coated in black selective material. The system was analyzed for different solar collector areas and storage capacities over several summer months. The solar fraction (f) was used as the primary performance metric. The results indicated that Type D collectors performed the best owing to their improved thermal insulation and selective absorption. Type A exhibited the lowest performance because of its higher heat losses. Types B and C yielded intermediate results. The study also examined the effect of five storage capacities (25, 50, 75, 100, and 125 kg of water per m²) and five collector areas (40, 60, 80, 100, and 120 m²) on system efficiency. Both parameters positively affected the thermal performance. This study aims to determine the thermal performance of a closed-loop solar water heating system for powering an absorption refrigeration machine by estimating the solar fraction under different conditions.
Ahmed Jasim Obaid, Hassan K. Al-Musawi, Majid Valizadeh
Within the last ten years, several modern technologies were invented, and different types of services were subscribed to and used in daily life. All these are in need of high data rate and wide coverage in respect to mobile communication, and it thus needs an advanced generation to meet these performances as dictated by the end users. This paper is intended to advocate radio-over-fiber technique in 5G systems, improving standards of techniques for ensuring effective wireless communications coverage. But the problem was an issue of nonlinear effect causing some failure in the system performance, especially at a distance of 400km in transmission and data rate impact at fifth generation-the data downloaded is up to 100 GBps. It uses a major concept from signal processing within NG5 RoF for transmission and reception. The defects take place starting off with the use of the transmitted signal at first instance within modulated 16QAM while it reaches receiving through the power account until the filtering to BER, which is taken up to distance transmission, initially starting from the 100 n right up to a distance of 400 km, hence. Worth remarking is that all the models presented in this report were simulated using Optisystem 18.
ABSTRACT As a country that implements sustainable development, Indonesia sets goals for energy efficiency, especially in the building sector. School buildings as representative building stock are the target of this study. The surveys and data collection were done from 28 high schools in Makassar. In the early stage of energy efficiency design, it is important to investigate the actual condition of school buildings as a foundation for further studies in energy consumption and energy efficiency planning. This paper comprehensively analyzes a typical school building, energy consumption patterns, and constant usage. Besides that, the effect of building conditions on school energy consumption is discussed. The findings of this study indicate that typical school buildings are usually in the south direction where site plan adjacent to the buildings around could lead to some challenges in energy efficiency. The energy consumption pattern reveals two categories, Category 1 has high fluctuation for monthly energy consumption and Category 2 has relatively flat consumption. Thus, two categories may have different site conditions. The study also found that the constant energy use, which assumes as a lighting energy consumption, is 5.87–7.78 W/m2 or 15.22–20.17 kWh/m2 per year.
Architecture, Architectural engineering. Structural engineering of buildings
Building information modelling (BIM) is an appreciated technology in the field of architecture and construction management. Collaboration of information in BIM has not been fully utilized in the structural engineering stream as many engineers keep on working with previous prevailing design approaches. Failure to adequately facilitate automation in design could lead to structural defects, construction rework, or even structural clashes, with major financial implications. Given the inherent complexity of large-scale construction projects, the ‘manual design and detailing’ of structure is a challenging task and prone to human errors. Against this backdrop, this study developed a 4D building information management approach to facilitate automated structural models for professionals designing all the elements required in reinforced concrete (RC) structures like slabs, beams, and columns. The main contribution of this study is to obtain structural models directly from architecture models automatically, which reduces effort and possible errors in the previous prevailing approaches. The framework enables execution of all the model design works automatically through coding. This is achieved by executing a script which is beneficial for integrated project delivery (IPD). The 3D structural model in BIM software presented in this study extracts and transfers the geometrical data and links these data in Industry Foundation Classes (IFC) files using integration facilitated by Python 3.6 and IFCopenshell. The developed automated programme framework offers a cost-effective and accurate methodology to address the limitations and inefficiencies of traditional methods of structural modelling, which had been carried out manually. The authors have developed a novel tool to extract structural models from architectural models without proprietary software, greatly benefiting BIM managers by enhancing 3D BIM models. This advancement toward Open BIM, crucial for the architecture, engineering, and construction (AEC) industry’s future, is accessible to educators and beginners and highlights BIM’s effectiveness in improving structural analysis and productivity. The core finding of this study is to generate a structural model from an architecture model by automating the script with Python integration of IFC and IFCopenshell. The merits of the developed framework are reduced clashes, more economical structural modelling, and fully automated smart work as functions of the IPD.
Abstract The sound field characteristics due to room modes are considered to have strong influences on the low‐frequency sound insulation between rooms in field. In this paper, the sound field analysis using the propagation mode expansion method proposed by the authors was applied to the test rooms where the dwelling rooms and the separating wall of an RC apartment building were reproduced. First, the proposed method was validated through the reconstruction of the expanded sound fields and the measurement of the incident directivity. Next, the comparison of the multiple geometries of the source room with two finishing conditions of the RC separating wall demonstrated the influence of the incident sound field on the sound insulation. The mechanism of the sound insulation between rooms was investigated using the proposed method. For the RC single wall, the sound field analysis showed an influence of mode matching between rooms on the low‐frequency transmitted sound. For the composite wall which was composed of the RC separating wall and the additional linings, it was demonstrated that the low‐frequency resonance transmission phenomenon is affected by the matching of the oblique incidence resonance frequency of the wall and the incident characteristics.
Architecture, Architectural engineering. Structural engineering of buildings
High Performance Concrete (HPB) is an innovative concrete that finds its place in modern constructions. New techniques for formulating and designing high-performance concrete have improved durability and achieved outstanding mechanical properties compared to conventional concrete, acause thanks to the improvement of its rheological qualities and its very limited porosity.
This has allowed to expand his field of employment especially in aggressive environments. Natural aggregates, frequently used, are now a non-renewable resource whose accessibility is continually declining.
Recycling of High Performance Concrete (HPC) waste in the form of recycled aggregates in the manufacture of a new range of high-performance recycled concrete with improved properties will lead to an understanding between performance and cost in order to achieve a resistant material with durability increased.
The aim of this study is to identify and analyse the characteristics of high performance recycled concrete aggregates based on two types of mineral additions (silica smoke, slag) which influence the properties of the concrete in a fresh and hardened state.
This study highlights the effects of substitution of natural aggregates by recycled aggregates (30% sand and gravel 25%, 50%, 100%) on the mechanical resistance of recycled high-performance concrete.
Examination of the results obtained has made it possible to establish the correlations between natural and recycled aggregates and on the physico-mechanical characteristics.
The analysis of these results also showed the interest of total or partial substitution of recycled aggregates based on silica smoke compared to recycled aggregates based on Algerian slag in the formulation of High Performance Recycled Concrete (HPRC) from the point of view of mechanical performance (strength).
Gold is one of the valuable metals and an important asset class for investors. People in India are emotionally attached to gold. Thousands of tonnes of idle gold are lying with Indian temples, trusts, and individuals. Investors consider capital appreciation; interest income and safety are major factors that influence buying of gold [1][4][7]. India is one of the biggest importers of gold every year. The government of India has introduced a few gold-related schemes to reduce gold imports. Sovereign gold bond [2] scheme and Re-vamped gold deposit scheme are introduced in the year 2015 under the Swarna Bharath initiative [9]. The present study is an attempt to find the association between awareness of investors and demographic factors towards gold ETFs, gold bonds, and gold deposits. The results reveal that there is a significant association at a 5% significance level between awareness of investors and all demographic factors used in the study except the gender of the respondent.
Kathryn Lucas-Healey, Hedda Ransan-Cooper, Hugo Temby
et al.
This paper represents the decentralised energy order as a matter of care: so as to make visible the unequal burden of care and to encourage active caring. It extends an emerging overlap that exists in studies of repair and maintenance of material objects from science and technology studies (STS) and an increasing interest in the creation and maintenance of relationships of care in energy systems. Inspiration is drawn from feminist STS work that calls attention to the continuous labour of repair and maintenance necessary to enact and sustain a socio-technical order. Fieldwork involved virtual interviews and small focus groups with 55 Australian householders who purchased decentralised energy technologies (solar, batteries and electric vehicles) and 18 intermediaries from industry and civil society. The analysis exposes how invisible care practices not only underpin householders’ material engagement with the energy system, but also how they are inextricably entangled with making a decentralised energy ‘order’ work in practice. Relying on ‘good hearted’ intermediaries is unlikely to be a workable basis for a functioning and fair energy system. An alternative approach is called for: an exploration of what a caring decentralised energy system might look like. 'Policy relevance' Care is significant for making energy systems work, and care has a role in building new energy orders and liveable futures. This research reveals that decentralised energy is enabled and made workable by the care people have for the future and their ability to take responsibility and action. It highlights those excluded from care-giving and -receiving, gaps that hamper the flow of care, and ways in which existing gender relations are reinforced by and reinforce these gaps and exclusions. Policymakers can recognise the importance, but also the limitations, of bureaucratic and market care in the energy system, and the need for policies and projects to recognise, support, and empower diverse abilities and care practices. This could be achieved through meaningful co-creation of policies, rules and processes. Energy businesses and intermediaries are encouraged to go beyond a transactional approach to installing technologies.
Architectural engineering. Structural engineering of buildings
Akinluyi Muyiwa L., Fadamiro Joseph A., Ayoola Hezekiah A.
et al.
This study reviewed the theoretical issues relating to morphological and psychological design issues in hospital building design evaluation. The study of morphological configurations design issues, concentrates on the elements of building, shape/form, the structure of the environment, the structural efficiency and the architectural appearance of the hospital building forms. The psychological design issues focused on the essential issues relating to Proximity, Privacy and Wayfindings. Through the literature review of previous models such as, Khan (2012) Operational Efficiency Model, Haron, Hamid and Talib Usability Framework, (2012), Zhao, Mourshed & Wright (2009) Model, Alalouch, Aspinall & Smith Model (2016) and Hill & Kitchen (2009). A conceptual framework for physical facilities design evaluation and satisfaction in hospital buildings was developed. The study, however, provides useful information for the development of a design framework that can inform policy on hospital buildings.
Natural light is essential in the design of a kindergarten class, but it must also be accompanied by an an artificial lighting system. Therefore using DiaLUX Evo, a kindergarten class was modeled with a specific zoning, where different types of light and building locations depending on the cardinal points were tried. Analyzing the information gathered, it was concluded that the best solution is option 3 in terms of location depending on the cardinal points and in terms of light color it was found that neutral light is optimal for a kindergarten classroom.
Architectural engineering. Structural engineering of buildings, Engineering design
Este artigo constitui-se em um estudo sobre o hotel em uma perspectiva teórica, histórica e crítica, buscando ampliar o conhecimento sobre as mutações das tipologias arquitetônicas na modernidade no contexto de um desígnio mais amplo e promover a discussão conceitual e transdisciplinar entre a arquitetura e o turismo. O objetivo do trabalho é compreender as articulações entre a gênese e metamorfoses do hotel na modernidade e as práticas sociais relacionadas à hospitalidade, à viagem e, mais recentemente, às atividades de lazer e turismo. O trabalho busca ainda discutir continuidades e descontinuidades no processo de transformação dessa categoria de edifícios, levantando como argumento a ideia de que os hotéis são, por excelência, tipologias arquitetônicas híbridas. Por fim, duas categorias de hotéis importantes surgidas na modernidade são analisadas: o “Grande Hotel” e o “Hotel de Turismo” que, por terem caráter híbrido, possuem significativo potencial de conservação na contemporaneidade, por intermédio de intervenções e estratégias de reuso para outros fins programáticos.
Architectural engineering. Structural engineering of buildings
Sharing with other colonial regimes the paradigm of a gap between the colonized society and colonizing one, urban policies undertaken by the French colonial administration in the Moroccan context carried a particular interest for a necessity of modernizing the local society through the urban space via a “civilizing mission”. The extensive operations of creation of new cities in Morocco generated new strategies of urban planning and management, which transformed not only the urban landscapes of cities and territories of these countries, but also went along with a deep mutation in the social structure within the cities. Willing to avoid previous mistakes in Algeria and to protect local culture from a “civilizational shock”, colonial cities built under the French protectorate by Hubert Lyautey, general resident of colonial administration, sought a the first place a separation between local population and European one. However, the subsequent approaches that followed evolved gradually towards a new order of spatial and socio-economical segregation that departed from the initial colonial policies; as the initial ethnical separation shifted to a socio-economical segregation, carried in the process, by complex socio-spatial dynamics in which the local society took part at and influenced the colonial administration and its spatial projections. By looking beyond the colonized/colonizing paradigm, this article aims, through the case of the city of Casablanca, to reassess the power of the local social dynamics. Stressing that while colonial policies initiated the shift to a modern city, social segregations that occurred after, carried by its own dynamics, need to be examined as a powerful process in reshaping our current cities.
Architectural engineering. Structural engineering of buildings
La industria de construcción genera una parte significativa de los residuos sólidos generados en los centros urbanos. En parte esto se debe a la falta de una cultura de reducción de generación o reutilización de los residuos. Este sector puede mejorar esta situación, tratando de desarrollar sistemas de gestión. El objetivo de este trabajo es presentar una propuesta para un sistema de gestión para planificar y controlar los residuos de la construcción en pequeñas y medianas empresas de construcción. Se llevó a cabo un estudio de caso en una empresa de Novo Hamburgo, Brasil. El sistema de planeamiento y control de residuos fue desarrollado con base en el sistema de producción existente en la empresa. El sistema propuesto fue testado en las obras de la empresa y los resultados apuntan a la viabilidad de implantación del sistema.
Architectural engineering. Structural engineering of buildings
O foco do trabalho é o ser humano, em seu caminhar, observar e fazer-se presente na contemplação. O trabalho propõe a aproximação de pessoas anônimas, o estranhamento do comum e a representação no espaço-tempo da vida de outros. Fazer um recorte desse corpo manifesto que está em ação nas ruas e trazê-lo para o mesmo ambiente em que ele foi capturado faz com que a presença de sua imagem gere novos vínculos com o espaço urbano, tanto no plano estético como no social. Isso se dá por ser a rua um território em constante transformação — um espaço de liberdade, que deve ser consumido, explorado e manifestado. É um ambiente onde é preciso que se esteja presente para haver alguma alteração. Ele estando vazio, gera uma ausência, e é exatamente essa ausência que gera um espaço passível de apropriação. A manifestação urbana ajuda a construir esse território. A expressividade cotidiana dos transeuntes da cena urbana é captada e impressa em tamanho real para compor cenários sugestivos que definem a essência do trabalho. Essas imagens incitam as pessoas nas ruas a questionar sua presença na ausência de um corpo-não-corpo, estabelecendo vínculos simbólicos na apropriação do espaço e do tempo da vida anônima. Abrem portas para mundos perceptivos novos, criam novos olhares e ampliam o horizonte, deixando a informação de sua presença em sua ausência. Assim, essas interferências urbanas convidam o expectador a uma fuga de seu próprio corpo. A face oculta do anônimo e a iconofagia1 das imagens (ora as imagens devoram os homens e ora estes as devoram), muitas vezes simultaneamente, criam conexões entre a imagem reproduzida e a inserida no espaço urbano com seus transeuntes reais.
Architectural engineering. Structural engineering of buildings
Este artigo visa elaborar um balanço crítico sobre a atuação governamental no que se refere aos assentamentos precários situados na área de proteção aos mananciais da metrópole paulistana, particularmente a bacia da represa Billings de 1991 a 2018. O olhar retrospectivo sobre a atuação ou a omissão do poder público, em diferentes períodos, fornece elementos para questionar de que forma a diretriz de recuperação ambiental contida da legislação estadual e nos programas de intervenção se efetivou no território dos municípios, destacando as consequências sociais. Para isso, a análise se estrutura em três períodos, nos quais identificam-se alterações na legislação e nos programas de intervenção e financiamento; e baseia-se em pesquisas documentais e empíricas, que se articulam à perspectiva teórica da ecologia política urbana para problematizar a urbanização da natureza em suas múltiplas dimensões.
Architectural engineering. Structural engineering of buildings
This article presents a parametric study on the lateral-torsional coupling behaviour of the simplified bidirectional asymmetric multi-storey dual lateral load-resisting model. The implementation process for establishing the simplification model is shown in an illustrative example on a three-storey reinforced concrete building system. Combined with the force–displacement relationships of the lateral load-resisting members and the inter-story restoring force models, the dynamic stiffness matrix and the equations of motion under different loading conditions can also be determined. On this basis, parametric analyses for the systems are carried out through the whole loading process from the elastic stage to the inelastic stage. Effects of uncoupled torsion to lateral frequency ratios (Ω) and the stiffness eccentricities on the frequencies are investigated. The analysis shows that the asymmetrical system with a smaller Ω value has a smaller torsional stiffness and a stronger lateral-torsional coupling effect. The effects of the eccentricities in both directions on the frequencies are remarkably different. Smaller Ω values and greater eccentricities lead to greater reductions in the effects of Ω and eccentricities on the frequencies in the inelastic stage.
A development of the ‘first-order storey pseudo-stiffness-based damage index’ of high-rise buildings is presented in this article. The proposed damage index is based on identification of an input set of one modal eigenpair, consisting of one modal frequency and the corresponding mode shape, overcoming the need and the difficulties of identifying multiple sets of eigenpairs in operational modal analyses of multistorey buildings. The calculation of first-order storey pseudo-stiffness-based damage index is expressed as a simple numerical procedure for comparison between the dynamic parameters of undamaged and damaged structures. The accuracy of the proposed damage assessment approach has been verified in two different tests – numerical and experimental. The numerical tests are based on the calculation of first-order storey pseudo-stiffness-based damage index in numerical models in which the structural damage is simulated with previously defined storey stiffness degradation. The experimental test consists of first-order storey pseudo-stiffness-based damage index accuracy test on the structure of the Urban Disaster Prevention Research Center, located in Tsukuba, Japan, and comparison to the results obtained by previously proven accurate damage detection method. The test results have shown that the proposed first-order storey pseudo-stiffness-based damage index index, based on the first modal eigenpair, can be applied as an instant damage detection method in structural health monitoring of multistorey buildings, providing the location and severity of structural damage.
Despite increasing attention is paid to the development of strategies and innovative technology solutions for the energy efficiency of building components and systems, especially in the residential sector not much has been deepened on the optimal management of the building-HVAC system. In relation to the specific Mediterranean climatic context of the city of Bari, and in reference to a single-family-residential buildings type, different solutions for the energy efficiency and its optimal management have been evaluated through dynamic energy and economic analyzes.
Architectural engineering. Structural engineering of buildings
Buildings designed with floors suspended on mega supporting structures (core tubes/frames) are referred to as suspended buildings. Such buildings can meet some practical requirements such as the gaining of large open spaces. Some aspects, including seismic performance and structural stability, however, are not completely understood by the engineering community. This motivated an investigation into the performance of suspended buildings subjected to gravity and ground earthquake motion. The stability of suspended floors and their mega supporting structures is discussed in relation to P-delta effect. A suspended-floor section is able to gain stiffness from gravity, but the stability of its mega supporting structure may be a problem due to the up-shifted gravity. This leads to a discussion of the storey-based stability method for assessing the critical load multipliers to be applied to the supporting frames. In view of the pros and cons of suspended buildings, a passive control system with three-performance levels is presented using pendulum floors and connection dampers to dissipate energy and avoid pounding. Optimal control system parameters were studied in order to help with the selection of connection stiffnesses and damping coefficients during the design of suspended buildings. Initial results show that, as opposed to a pendulum TMD, the large suspended-floor masses themselves play a key role in reducing the seismic response, and buildings are able to be designed as types of suspended systems which are effective against strong earthquake motion combined with gravity.