Low computational cost technique for predictive management of thermal comfort in non-residential buildings

In France, non-residential buildings account for a significant part of energy consumption. A large part of this consumption is due to HVAC (Heating, Ventilation and Air-Conditioning) systems, which are in most cases poorly handled. The present work deals with an efficient approach allowing energy consumption to be minimized while still ensuring thermal comfort. We propose a predictive control strategy for existing zoned HVAC systems and consider the PMV (Predicted Mean Vote) index as a thermal comfort indicator. In order to test this strategy, we modelled a non-residential building located in Perpignan (south of France) using the EnergyPlus software. The twofold aim is to limit the times during which the HVAC sub-systems are turned on and to ensure a satisfactory thermal comfort when people are working in the considered building. This predictive approach, computationally tractable, allows thermal comfort requirements to be met without wasting energy.     

Analysis of early-design timber models for sound insulation

Timber construction is associated with a low carbon footprint and offers a high degree of sustainability. However, it poses challenges considering sound insulation. Acoustic analyses, which could require major expensive and time consuming changes in the building design, are typically performed once the design is already in the detailed stage. By using building information modelling (BIM), it is possible to shift the planning of the building physics, including acoustic analysis, to earlier phases. To make this possible, building models must include all the information necessary to perform acoustic analyses. One important part of acoustic analysis is identifying junctions between elements and map them to the junction types in standards. Until now, this investigation involves tedious manual processing for extracting multiple topological dependencies between different elements. Hence, this paper presents a framework for a seamless workflow between building models and acoustic analysis tools, based on an analysis of data models. The framework extracts and analyzes the element types, their geometry, and the connections of the individual elements in relation to each other. Through topological reasoning, along with a set of logical rules, the proposed framework identifies fifteen types of junctions, which can be distinguished acoustically for timber construction. The approach was evaluated in a prototypical implementation using a real-world model based on Industry Foundation Classes (IFC) as an example, in which the potential connection types were successfully extracted. This paper shows that junction analysis can be done with a geometric analysis to fill in missing semantic information about junctions of elements from the original data model.     

Objective and subjective evaluation of the acoustic comfort in classrooms

The acoustic comfort of classrooms in a Brazilian public school has been evaluated through interviews with 62 teachers and 464 pupils, measurements of background noise, reverberation time, and sound insulation. Acoustic measurements have revealed the poor acoustic quality of the classrooms. Results have shown that teachers and pupils consider the noise generated and the voice of the teacher in neighboring classrooms as the main sources of annoyance inside the classroom. Acoustic simulations resulted in the suggestion of placement of perforated plywood on the ceiling, for reduction in reverberation time and increase in the acoustic comfort of the classrooms.     

A flexible building management framework based on wireless sensor and actuator networks

Future buildings will be constantly monitored and managed through intelligent systems that allow having information about the building health, keeping a good comfort level for the building inhabitants and optimizing the energy spent. Despite many WSN programming frameworks have been to date developed and, in some cases, applied to support monitoring of buildings, none of them possesses all the specific features needed to develop WSN-based building applications. In this article a multi-platform domain specific framework based on Wireless Sensor and Actuator Networks (WSANs) for enabling efficient and effective management of buildings is presented. The proposed Building Management Framework (BMF) provides powerful abstractions that capture the morphology of buildings to allow for the rapid development and flexible management of pervasive building monitoring applications. The functionalities of the framework are shown in an emblematic case study concerning the SmartEnergyLab that is an effective operating scenario related to the monitoring of the usage of workstations in laboratories and offices. Finally, a performance evaluation of a WSAN running the BMF in terms of network usage and system lifetime is shown.     

Building a sonar map in a specular environment using a singlemobile sensor

The physical properties of acoustic sensors are exploited to obtain information about the environment for sonar map building. A theoretical formulation for interpreting the sensor databases on the physical principles of acoustic propagation and reflection is presented. A characterization of the sonar scan that allows the differentiation of planes, corners, and edges in a specular environment is described. A single sensor mounted on an autonomous vehicle in a laboratory verifies the technique. The implications for sonar map building and the limitations of differentiating elements with one sensor are discussed     

城市有轨电车引发的建筑结构振动响应

为分析城市有轨电车运行引发的建筑结构振动舒适度,基于MATLAB设计结构振动舒适度的计算程序,可结合结构健康监测系统的监测数据对建筑结构的振动舒适度进行分析。采用某有轨电车运行中的实测数据,分析车辆段和行车段电车引发的振动,研究有轨电车的振动响应特性。分析结果表明：有轨电车运行引发的高频振动传至上盖结构几乎已完全消散;上盖结构的振动频率集中在16~20 Hz区间,以有轨电车的低频振动和结构相关附属机器的振动为主。减小有轨电车的行驶速度、增加建筑物与振动源的距离或控制楼内附属机器的振动可明显控制振动。在加速过程中,电车与地面和轨道会产生共振,因此存在振动加速度级的极大值。     

基于温湿度的模糊传感器舒适度合成法研究

人类舒适感涉及多方因素 ,具有主观性、多维性和模糊性 ,舒适度传感器是未来传感器发展应用的一个趋势。从应用的角度 ,提出并探讨了基于温湿度的模糊传感器舒适度合成方法 ,相关参量的隶属函数取典型的正态分布 ,考虑到多维概念合成的不完备性 ,提出了由例子推导建立规则库的方法。     

Multi-objective optimization of a hatchback rear end utilizing fractional factorial design algorithm

Air flow has significant effects on fuel consumption, performance, and comfort. Decreasing drag coefficient enhances fuel consumption and vehicle performance. Moreover, omitting or reducing the power of aerodynamic noise sources provides passengers comfort. In this paper, optimization of a hatchback rear end is conducted considering drag and aerodynamic noise objectives. To this end, five geometrical parameters of the hatchback rear end are chosen as design variables in two levels. Numerical simulation is applied to survey air flow features around the models in the wind tunnel. To reduce the number of runs, fraction factorial design algorithm is applied to generate layout of the simulations which decreased the number of case studies to half. Main and interaction effects of these factors on drag coefficient and acoustic power of the rear end source are derived using analysis of variance. Optimum level for each parameter is chosen considering simultaneous drag and noise goals. Finally, characteristics of air flow and acoustic power around optimum model are discussed.

     

Acoustic evaluation and adjustment of an open-plan office through architectural design and noise control

Arranging office space into a single open room offers advantages in terms of easy exchange of information and interaction among coworkers, but reduces privacy and acoustic comfort. Thus, the purpose of this work was to evaluate the acoustic quality of a real open-plan office and to propose changes in the room to improve the acoustic conditioning of this office. The computational model of the office under study was calibrated based on RT and STI measurements. Predictions were made of the RT and STI, which generated the radius of distraction r(D), and the rate of spatial decay of sound pressure levels per distance doubling DL(2) in the real conditions of the office and after modifications of the room. The insertion of dividers between work stations and an increase in the ceiling's sound absorption improved the acoustic conditions in the office under study.     

计算机技术在楼宇智能化方面的应用

建筑技术的发展,要求自动化技术提高在建筑工程中得以运用,以提高建筑功能和建筑的舒适性.计算机的高速发展和广泛引用,其已经涉及到了人类生活的各个方面.楼宇智能化是计算机技术在建筑方面运用的必然趋势,本文从介绍楼宇智能化的概念和特征入手,分析计算机在我国楼宇智能化的应用现状和其未来的发展趋势.     

Expected versus experienced neck comfort

There is certainly room for economy‐class travelers to make their trips more pleasant. A travel pillow might improve comfort. In this study, the comfort expectations and experience of travel pillows were examined. Comparing these 2 aspects indicated that it is not always possible to predict the comfort experience associated with a product based on a picture, and that there is a discrepancy between expected and experienced comfort. Experienced comfort is highest for travel pillows that restrict head movements in all directions in order to maintain a neutral posture. The results of this study also support earlier studies that suggested that discomfort experience can be predicted by observing the number of participants’ in‐seat movements; more movements result in higher experienced discomfort.     

Designing buildings for minimal energy consumption

A dynamic model for predicting the thermal behaviour and energy consumption of a full-scale building has been developed. The model can include most of the design and climatological factors affecting the building. The time-dependent equation for the heat flow through the walls is converted into an implicit scheme and solved numerically. Special effort has been devoted to producing a model capable of aiding the architect during the various steps of building design, so as to approach thermal comfort with minimal energy consumption. The results are presented in graphical form, which allows the architect to detect easily the crucial factors in the thermal performance of the building.     

Multi-objective optimization design of a complex building based on an artificial neural network and performance evaluation of algorithms

While optimization studies focusing on real-world buildings are somewhat limited, many building optimization studies to date have used simple hypothetical buildings for the following three reasons: (1) the shape and form of real buildings are complex and difficult to mathematically describe; (2) computer models built based on real buildings are computationally expensive, which makes the optimization process time-consuming and impractical and (3) although algorithm performance is crucial for achieving effective building performance optimization (BPO), there is a lack of agreement regarding the proper selection of optimization algorithms and algorithm control parameters. This study applied BPO to the design of a newly built complex building. A number of design variables, including the shape of the building’s eaves, were optimized to improve building energy efficiency and indoor thermal comfort. Instead of using a detailed simulation model, a surrogate model developed by an artificial neural network (ANN) was used to reduce the computing time. In this study, the performance of four multi-objective algorithms was evaluated by using the proposed performance evaluation criteria to select the best algorithm and parameter values for population size and number of generations. The performance evaluation results of the algorithms implied that NSGA-II (with a population size and number of generations of 40 and 45, respectively) performed the best in the case study. The final optimal solution significantly improves building performance, demonstrating the success of the BPO technique in solving complex building design problems. In addition, the findings on the performance evaluation of the algorithms provide guidance for users regarding the selection of suitable algorithms and parameter settings based on the most important performance criteria.     

基于乘坐舒适、节能的电梯变频调速系统设计及实现

电梯作为高层建筑中大量使用的机电一体化设备,为了改善乘坐的舒适度、节能,电梯的控制系统中广泛使用交流变压变频调速,作为变压变频控制装置,变频器以其成熟的技术和可靠性被应用于电梯控制系统中,与其他类型交流调速系统相比具有运行效率高、节能效果显著,电梯运行乘坐舒适等优点。本文以日本富士电梯专用变频器5000G11UD为控制器,组成电梯变频调速系统,从理论上分析了实现电梯乘坐舒适、节能的控制关键点,并给出了实际操作方法,具体应用取得了较好的效果。     

Prioritised objectives for model predictive control of building heating systems

Advantages of Model Predictive Control (MPC) strategies for control of building energy systems have been widely reported. A key requirement for successful realisation of such approaches is that strategies are formulated in such a way as to be easily adapted to fit a wide range of buildings with little commissioning effort. This paper introduces an MPC-based building heating strategy, whereby the (typically competing) objectives of energy and thermal comfort are optimised in a prioritised manner. The need for balancing weights in an objective function is eliminated, simplifying the design of the strategy. The problem is further divided into supply and demand problems, separating a high order linear optimisation from a low order nonlinear optimisation. The performance of the formulation is demonstrated in a simulation platform, which is trained to replicate the thermal dynamics of a real building using data taken from the building.     

Distributed control for a multi-evaporator air conditioning system

An autonomous hierarchical distributed control (AHDC) strategy is proposed for a building multi-evaporator air conditioning (ME A/C) system in this paper. The objectives are to minimize peak demand and energy costs, and to reduce communication resources, computational complexity and conservativeness while maintaining both thermal comfort and indoor air quality (IAQ) in acceptable ranges. The building consists of multiple connected rooms and zones. The proposed control strategy consists of two layers. The upper layer is an open loop optimizer, which only collects local measurement information and solves a distributed steady state resource allocation problem to autonomously and adaptively generate reference points, for low layer controllers. This is achieved by optimizing the demand and energy costs of a multi-zone building ME A/C system under a time-of-use (TOU) rate structure, while meeting the requirements of each zone’s thermal comfort and IAQ within comfortable ranges. The lower layer also uses local information to track the trajectory references, which are calculated by the upper layer, via a distributed model predictive control (DMPC) algorithm. The control strategy is distributed at both layers because they use only local information from the working zone and its neighbors. Simulation results are provided to illustrate the advantages of the designed control schemes.     

An on-the-road experiment into the thermal comfort of car seats

This paper presents an evaluation of thermal comfort in an extended road trial study. Automobile seats play an important role in improving the thermal comfort. In the assessment of thermal comfort in autos, in general subjective and objective measurements are used. Testing on the road is very difficult but real traffic conditions affect the comfort level directly, as well as the driver's experience to real conditions. Thus, for such cases real traffic situations should not be neglected in the evaluation of comfort. The aim of this study was to carry out, on an extended road trial study, an evaluation of thermal comfort using human subjects. In the experiments used, the 100% polyester seat cover had three different cover materials, which were velvet, jacquard and micro fiber. All experiments were carried out on a sunny day with ten participants over 1h. They were carried out at air temperatures of 25 degrees C in a Fiat Marea 2004, which had an automatic climate function. Skin temperature at eight points and skin wettedness at two points on the human body were measured during the trials. Participants were required to complete a questionnaire of 15 questions, every 5 min. It can be concluded that there was negligible difference in participants' reported thermal sensation between the three seats. According to objective measurement results, all seat cover materials have the same degree of thermal comfort. On the road the participants feel warmer around their waist than any other area of the body. It was suggested that the effects of real traffic conditions must be accounted for in comfort predictions.     

基于PLC的电梯运行速度控制设计与实现

电梯是高层建筑中垂直运行的交通运输工具,其上升、下降、停靠的平稳性、舒适性受到人们的关注。首先介绍了电梯的工作原理、控制主回路,分析了电梯运行舒适性的主要影响因素,最后用三菱PLC实现了电梯运行速度的控制设计。     

Joint angles of isocomfort for female subjects based on the psychophysical scaling of static standing postures

This study investigated the joint angles of isocomfort (JAIs) for females based on the psychophysical scalings for static standing postures held for 60 s, which were obtained in a laboratory experiment. The subjects were instructed to rate their comfort levels for varyious joint postures by using the free modulus method of magnitude estimation. The comfort scores for the joint postures and the related verbal comfort categories were subjected to regression analysis in order to obtain the JAIs corresponding to verbal categories. The results showed that the JAIs were significantly different depending upon the joints and joint postures investigated (p < 0.01), and that the JAIs for female subjects were significantly different than those for males (p < 0.01) which had been obtained in an earlier study (Kee and Karwowski, 2001). Compared to the corresponding range of joint motion values, the JAIs for hip postures were the smallest of all joint postures dealt with in this study, while those for the neck were the largest of all postures, which means that hip postures are more stressful than any other joint posture. Based on this study, it is recommended that the gender-based JAI values should be used for design applications.