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Regression-based Model for Predicting Simulated vs Actual Building Performance Discrepancies

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Procedia Computer Science 2024年 251卷 633-638页

作者： Ivan Izonin Roman Tkachenko Rosana Caro Antonio LaTorre de la Fuente Kyrylo Yemets Stergios Aristoteles Mitoulis Department of Artificial Intelligence Lviv Polytechnic National University Kniazia Romana str. 5 Lviv 79905 Ukraine Department of Civil Engineering School of Engineering University of Birmingham Birmingham B15 2TT United Kingdom Department of Construction and Technologies in Architecture Escuela Técnica Superior de Arquitectura Universidad Politécnica de Madrid Avenida Juan de Herrera 4 28040 Madrid Spain Center for Computational Simulation Universidad Politécnica de Madrid Avenida Juan de Herrera 4 28040 Madrid Spain

Accurately predicting discrepancies between simulated and actual building performance is becoming increasingly crucial in building management and optimization of e.g., Digital Twins and energy efficiency assessments. This challenge is amplified by the growing dependence on simulation models which predict building behavior, energy consumption, and operational efficiency. Despite advancements in simulation technology, aligning these models with real-world data remains a persistent challenge. This study addresses this challenge by developing a regression-based model designed to predict discrepancies between simulated and actual operational characteristics of buildings. The model identifies differences between synchronized time series data to generate a new series that highlights these discrepancies. By employing a sliding window technique, the model processes actual operational data to predict discrepancies. They implemented this approach using AdaBoost and Random Forest, evaluating performance across eight datasets of Indoor Air Temperature from two cities. The results demonstrate that the Random Forest algorithm significantly outperforms AdaBoost, with improvements in R² scores of up to 23 percent and reductions in RMSE by up to 4.5 times.

关键词： regression model performance gap modeling gap discrepancy simulation building performance time series EnergyPlus

Directivity Improvement of MIMO Array Antenna using Novel Eight Element Array Configuration

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Directivity Improvement of MIMO Array Antenna using Novel Ei...

Advancement in Electronics & Communication engineering (AECE), International Conference on

作者： Alaa M. Lafta Abdul Razzaq T. Zaboun Shakhlokhon Kosimova Alaa. Shather Hawraa Ali Sabah Haider Alchilibi National University of Science and Technology Dhi Qar Iraq Forensic sciences department Al-Esraa University College Baghdad Iraq Department of Architecture Fergana Polytechnic Institute Fergana Uzbekistan Department of Computer Engineering Technology Al Kitab University Altun Kopru Kirkuk Iraq Medical Laboratory Techniques Department Al-Farahidi University Baghdad Iraq

In this study, the Directivity of the Microstrip Patch MIMO Antenna is a Novel Eight element array configuration in comparison with its performance of a Single element patch antenna. Directivity improvement and Return loss measured for different frequencies and values are compared with a Single element patch antenna. Novel Eight element MIMO array antenna is designed and compared with a Single patch element antenna. In this work, there are two groups (Eight element patch & Single element patch) each consisting of 20 samples with pre-test power or G-power of 80%. The mean Return loss in the Novel eight element MIMO array antenna is -18.39 dB and in the Single element antenna is -15.21 dB. These results showed that the Novel eight element array exhibited a better Directivity improvement (4.483 dB) than the single element antenna (2.261 dB) with the two-tailed significance of (p < 0.05). The Directivity improvement is significantly better for a Novel eight element array antenna when compared with a single element patch antenna.

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A Method for Estimating Occupant Carbon Dioxide Generation Rates

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SSRN 2023年

作者： Li, Yanyan Gao, Siru Fang, Tianyu Gao, Yunfei Liu, Shichao Zhang, Hui Wang, Xue Zhai, Yongchao State Key Laboratory of Green Building Xi'an University of Architecture and Technology Shaanxi Xi’an710055 China College of Architecture Xi'an University of Architecture and Technology Shaanxi Xi’an710055 China School of Architecture and Design China University of Mining and Technology Jiangsu Xuzhou221008 China School of Civil and Transportation Engineering Guangdong University of Technology Guangdong Guangzhou510006 China Department of Civil Environmental and Architectural Engineering Worcester Polytechnic Institute WorcesterMA01609 United States Center for the Built Environment UC Berkeley BerkeleyCA94720 United States

In most applications of indoor CO2, such as building ventilation rate estimation and demand-controlled ventilation, the CO2 generation rate of building occupants is a crucial parameter. Currently, ASTM D6245-18 provides an estimation formula for the CO2 generation rate, but there are indications that its results tend to be underestimated. This paper utilized more than 7,200 sets of CO2 generation rate data from over 1100 participants aged 5 to 70 to propose a segmented regression model for estimating CO2 generation rates based on gender, age, and activity intensity as independent variables. Based on the patterns of CO2 generation rate in relation to age, two critical age breakpoints were identified: 9/10 years for girls/boys entering puberty and 13/15 years for girls/boys entering the stable growth phase. The reliability of the established model was validated through literature-based data across various scenarios. The results revealed that using the activity intensity determined by the recommended metabolic rates in the ASHRAE Handbook, our estimations were closer to the experimental values compared to ASTM D6245-18, which required higher metabolic rates for compensation. The prediction method in this paper requires only age, gender, and activity metabolic rate to estimate the mean CO2 generation rate for different population groups, offering a simple calculation approach for key parameters in CO2 applications within buildings. © 2023, The Authors. All rights reserved.

关键词： Metabolism

Investigating the Size Effect of Calcareous Sand Using a Critical State-Based Model with Cma-Es Optimization

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SSRN 2024年

作者： Wang, Xing Yin, Zhen-Yu Jin, Yin-Fu Peng, Mao-Zhu Cui, Jie School of Architecture and Civil Engineering Xihua University Chengdu610039 China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong College of Civil and Transportation Engineering Shenzhen University Shenzhen518060 China State Key Laboratory of Intelligent Geotechnics and Tunnelling Shenzhen University Shenzhen518060 China School of Civil Engineering Guangzhou University Guangzhou510006 China Earthquake Engineering Research & Test Center Guangzhou University Guangzhou510405 China

Particle size of natural calcareous sands (CSs) varies significantly. It is of great interest for engineering practice if the mechanical behaviours of coarse-grained CSs can be easily extended from behaviours of fine-grained CSs using a constitutive model, for which the size effect is the key issue. For this purpose, drained triaxial test results on CSs with five different particle sizes are first re-interpreted in this study to reveal this effect. The critical state-based sand constitutive model—SIMSAND model considering particle breakage effect is adopted for describing mechanical behaviours of CSs. The optimization theory with the covariance matrix adaptation evolutionary strategies (CMA-ES) algorithm is integrated with SIMSAND for identifying model parameters of five CSs. The applicability of the SIMSAND model to CS and the rationality of CMA-ES algorithm in determining model parameters are thus verified. Then, based on the analysis of model parameters of five CSs, six size-dependent parameters are selected. Six relationships between the size-dependent parameters and particle size are proposed based on three CSs, together with which the SIMSAND model can consider both particle size and breakage effects. The rationality of the model is verified by simulating tests of another two CSs (one for interpolation and the other for extrapolation). The results of this study can lay a foundation for predicting the mechanical behaviour of CSs with different particle sizes. © 2024, The Authors. All rights reserved.

关键词： Constitutive models

Numerical Modeling of the Mechanical Response of Asphalt Concrete in Tension and Compression

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SSRN 2023年

作者： Tan, Zhifei Leng, Zhen Jelagin, Denis Cao, Peng Jiang, Jiwang Ashish, Prabin Kumar Li, Rui Zou, Fuliao Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hong Kong Department of Civil and Architectural Engineering KTH Royal Institute of Technology Brinellvägen 23 Stockholm10044 Sweden College of Architecture and Civil Engineering Beijing University of Technology Beijing China School of Transportation Southeast University Jiangsu Nanjing210000 China Department of Civil Engineering Indian Institute of Technology Kanpur India National & Local Joint Engineering Research Center of Transportation and Civil Engineering Materials Chongqing Jiaotong University Chongqing China

Due to the aggregate contact effect, asphalt concrete (AC) shows tension-compression (TC) asymmetry, i.e., different properties in tension and compression (T&C). This asymmetry may profoundly affect AC’s performance and deterioration in the field, but very few studies have been performed to quantify this behavior. This study aims to quantitively characterize the mechanical response of AC in T&C through numerical micromechanical modeling. To this end, the TC properties of three AC mixtures: the gap-graded SMA10, dense-graded AC20, and open-graded mixtures PA13, were evaluated experimentally and numerically. The image-based AC models with contact region (CR) were generated to account for the aggregate contact effect in AC modeling. The measured and predicted master curves for AC in T&C agreed qualitatively and showed significant asymmetry by displaying substantially higher moduli but lower phase angles in compression than in tension. However, this asymmetry weakened with increasing frequencies. PA13 showed the most remarkable asymmetry among the three mixtures, followed by SMA10 and AC20. In addition, the local stress and strain distributions in AC mixtures were also examined statistically, and the influence of loading mode and rate on the stress and strain localization was discussed. It was found that the aggregate phase displays much higher stress but lower strain than the matrix phase. This trend is more remarkable in compression and at low frequencies. The outcomes of this study are expected to the design of more durable AC. © 2023, The Authors. All rights reserved.

关键词： Finite element method

Mechanisms of Recycled Fine Aggregates With Different Saturation Degree on Mechanical Properties and Autogenous Shrinkage Behaviour Of Ultra-High Performance Concrete

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SSRN 2024年

作者： Cheng, Shukai Wang, Hongtao Li, Shunkai Chen, Xuyong Chen, Kang Zhang, Dongfang Fan, Zhihong Lu, Jian Xin School of Civil Engineering and Architecture Wuhan Institute of Technology Wuhan430074 China Hubei Provincial Engineering Research Center for Green Civil Engineering Materials and Structures Wuhan430074 China Guangxi Key Laboratory of Green Building Materials and Construction Industrialization Guilin University of Technology Guilin541004 China CCCC Fourth Harbor Engineering Institute Co. Ltd Guangzhou510230 China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

To curtail the over-exploitation of natural aggregates and alleviate the shortage of non-renewable resources, the usage of construction and demolition (C&D) waste provides new fields of application in the building industry. Recycled fine aggregate (RFA) obtained from C&D waste has high porosity and water absorption and releasing characteristics that potentially mitigate excessive autogenous shrinkage of ultra-high performance concrete (UHPC). RFA was utilized to substitute quartz sand in the preparation of low-carbon UHPC. Additionally, the workability, compressive strength, autogenous shrinkage, resistance to chloride ion penetration, and microstructure of UHPC incorporating RFA with different saturation degree (0, 50%, and 100%) were explored. The findings indicated that the degree of saturation and content of RFA were the key factors that affected the compressive strength and autogenous shrinkage of UHPC. The early autogenous shrinkage of UHPC was significantly reduced as the saturation degree and content of RFA increase, while compressive strength was not obviously affected. Overall, the presence of RFA with 20% replacement and 100% saturation degree was beneficial for mitigating autogenous shrinkage and enhanced the 28-day compressive strength. Compared to UHPC without RFA, the 28-day compressive strength increased by 16.6%, while its 7-day autogenous shrinkage decreased by 90.47%. Furthermore, the incorporation of 20% RFA with 100% saturation degree exhibited an efficient internal curing effect, thus improved the hydration degree, and decreased the porosity of UHPC. This study successfully provides a practical method for preparing environmentally friendly and low-shrinkage UHPC using RFA with different saturation degree. © 2024, The Authors. All rights reserved.

关键词： Ultra-high performance concrete

Effects of Speech Intelligibility and Reverberation Time on the Serial Recall Task in Chinese Open-Plan Offices: A Laboratory Study

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SSRN 2023年

作者： Kang, Shengxian Mak, Cheuk Ming Ou, Dayi Zhou, Xinxin Department of Building Environment and Energy Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong School of Architecture Huaqiao University Xiamen361021 China State Key Laboratory of Subtropical Architecture Science South China University of Technology Guangzhou510640 China Guangzhou Design Institute Group CO. LTD. Guangzhou510620 China

Speech intelligibility is an essential index for evaluating acoustic performance in open-plan offices. Both speech-to-noise ratio (SNR) and reverberation time (RT) are critical parameters for determining the Speech Transmission Index (STI). STI is an important parameter for the objective prediction of speech intelligibility. Many studies explored the effects of speech intelligibility on work performance and acoustic environmental perceptions in open-plan offices by changing the SNR to obtain various STI conditions. However, few studies research how RT affects speech intelligibility and then influences work performance and perceptions of acoustic environments in open-plan offices. This study conducted a laboratory experiment to identify the changing trends of work performance and acoustic environment perceptions with the increase in STI under different RT conditions and to explore how room RT affects work performance and perceptions of the acoustic environment under the same STI condition. The acoustic conditions tested in this study varied in speech intelligibility (STI of 0.21, 0.42, and 0.61) and reverberation time (RT of 0.4s and 1.4s). The main outcome of this study is that occupants have less mental workload, faster task completion speed, and higher acoustic adaptability in a long RT environment compared to a short RT environment at an STI of 0.42. Furthermore, the data show a decreased work performance and an increased speech disturbance with the increase in STI in the short RT environment, while that trend was not observed in the long RT environment. The effects of STI conditions on occupants may differ by gender and noise sensitivity. © 2023, The Authors. All rights reserved.

关键词： Speech intelligibility

'Do It Yourself' and 'digital fabrication' for new way of founding life

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'Do It Yourself' and 'digital fabrication' for new way of fo...

World Sustainable Built Environment - Beyond 2020, WSBE 2020

作者： Parisi, N. Department of Civil Engineering Sciences and Architecture DICAR Polytechnic University of Bari 4 Via Edoardo Orabona Bari BA70125 Italy

In architecture, 'Do It Your Self' has always been a prerogative of those who need to build a home or a place dedicated to a life necessity with few resources. Even today, as in the past, self-construction is applied in very poor contexts and is implemented using traditional techniques and technologies. Today, however, the new dimension of Digital Fabrication offers a completely new scenario in architecture, including the world of 'Do It Your Self'. Machines and robots can enhance the possibilities available to those who want to get involved in it. Several companies innovate production processes by connecting the construction traditions of the past with new digital technologies. Young communities in search of self-determination feel the need to be personally involved in the regeneration and foundation of their living environment. Thus, the designer becomes a technical process consultant in the production and an animator of the community that builds its own architecture. Through four examples applied in the four editions of the International Summer Academy 'Self Made architecture', the FabLab team of the polytechnic University of Bari proposes a new approach to lead the new urban and peri-urban communities to found again their own places of life. The latest experimentation concerns the fourth edition still in the planning phase focused on the application of additive printing in architecture through the use of a mixture of raw earth. This technological advancement can represent a major resource to root the 'Do It Yourself' approach in the processes of Self-determination of local communities. This project results from the collaboration of the FabLab Poliba group with the development and research department of WASP, an Italian leading company in 3D printing, and from the scientific collaboration between the polytechnic University of Bari and the Faculty of architecture of Damascus. © Published under licence by IOP Publishing Ltd.

关键词： architecture

Producing sustainable concrete with plastic waste: A review

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Environmental Challenges 2022年 9卷

作者： Almohana, Abdulaziz Ibrahim Abdulwahid, Mohanad Yaseen Galobardes, Isaac Mushtaq, Jasir Almojil, Sattam Fahad Department of Civil Engineering Faculty of Engineering King Saud University Saudi Arabia Department of Civil Engineering Faculty of Engineering Koya University Iraq School of Architecture Planning & Design Polytechnic University Mohammed VI Morocco Environmental Consultant Tehkeek International India

Plastics are cheap, lightweight, versatile, and readily accessible material. The utilization of plastic has become a necessary facet of our day-to-day lives, and its production has risen exponentially in the last 50 years. As a result, there is an increase in the generation of waste related to plastic that leads to undermining the environment. This encourages researchers to use this waste in concrete manufacturing as a sustainable material. However, this paper reviews recent research on how the utilization of recycled plastic in concrete is an effective solution to enhance sound and thermal insulation. The aggregate comprises the largest and heaviest portion of concrete, which accounts for 85% of its weight. Besides, the plastic has a low density compared to the aggregate. As a result, the use of plastic waste as a partial replacement (50% to 75%) for the total aggregate significantly boosts the efficiency of thermal and sound lightweight concrete insulation. In addition, the cost of its manufacturing is drastically diminishing in comparison to that of ordinary concrete, and plastic can be installed and utilized quickly with less labor due to its lightweight nature. Plastic waste may be considered a typical material for the production of lightweight green concrete that can be used as a non-structural component in building construction. © 2022

关键词： Concrete Economic Insulation Lightweight concrete Plastic waste Sustainability