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Production of sludge as waste in pulp and paper plants can be considered as one of the serious environmental problems that have to be solved. While landfilling is not a suitable solution from the environmental point of view, thermal treatment proved to be the most appropriate one.This paper describes an efficient way of processing sludge including waste-to-energy aspects. A thermal treatment unit with a capacity of more than 100 tons of wet sludge per day had been built in a large pulp and paper plant some years ago. This pulp and paper plant is located in a mining area. When built, this unit was quite modern. However, because of more and more sweeping environmental laws affecting the process industry, the unit needed a complete retrofit. The retrofit has been realised in three stages.A brief description of the unit for the thermal treatment of sludge is as follows: the waste sludge (after transport from a sludge storage system) is burnt in a multiple hearth incinerator with a fluidised-bed chamber. Then, the flue gas enters a secondary combustion chamber (afterburner chamber). During the first stage of retrofit, only a part of heat from flue gas was utilised for heat recovery (pre-heating air for combustion and fluidisation) and a contact cooler was involved in the unit. The second stage of retrofit can be characterised as a “waste-to-energy” one. The contact cooler was replaced by a system for preheating water for steam generation. Off-gas cleaning system consists of a filter for particulate removal and a three-stage scrubber system. (Several alternatives of retrofit were considered and simulated and the most promising one was selected.) [Copyright &y& Elsevier]

The article offers information on chronic obstructive pulmonary disease, initiation of nocturnal non-invasive ventilation at home is non-inferior to initiation during a hospital admission.

In a construction environment, project scheduling is an essential tool to measure the success of all projects. This research paper will use project crashing of Activity to decrease the project completion schedule through the CPM method of time-cost trade-off and to minimize project cost. It includes linear programming with the aid of Microsoft Excel Solver to determine the result. And at the end of the research paper, it will show the impact of crashing the activities for the HVAC mechanical installation in a project for both normal and crash time, which displays that the selected Activity that had been crashed generated an increase of 9.8 % total cost from the total project cost. [ABSTRACT FROM AUTHOR]

Mixed-mode ventilation system (MMVS) can significantly decrease the energy consumption of Egyptian office buildings while meeting indoor air quality requirements and thermal comfort of occupancy. This paper studies the effect of using mixed-mode ventilation system (MMVS) in achieving both energy efficiency and thermal comfort in office buildings. The research specifically focuses on investigating the energy-saving potential and thermal performance of existing office buildings in Egypt by merging natural ventilation (NV) with mechanical ventilation (MV) to reach an effective mixed-mode ventilation system (MMVS). Additionally, an energy performance simulation was used to study how to achieve thermal comfort and the building's indoor temperature. Firstly, a selected office building in Cairo was used as a case study, and its thermal performance was studied by simulation. Secondly, site measurements were conducted to record the real thermal performance of the tested office building. These measurements were used for the validation phase. The validation demonstrated a satisfactory agreement between the building simulation and measurement data for air temperature (T) and relative humidity (RH). Thirdly, building energy simulations and analysis were used for testing the energy performance and thermal comfort of the tested scenarios that have different alternatives in the operation settings. The results revealed that it is possible to increase the thermal comfort hours by merging natural ventilation and applying the mixed-mode ventilation system only by changing the operation settings on the MMVS performance. The building's annual energy consumption was reduced by approximately 27 % compared with the use of HVAC in the building. Natural Ventilation hours increased by approximately 27 % to reach 427 hours (h) and the HVAC hours decreased by 17 % to reach 898 hours (h). [ABSTRACT FROM AUTHOR]

Astronauts are at risk for pneumothorax, a condition where injury or disease introduces air between the chest wall and the lungs (i.e., the pleural cavity). In a worst-case scenario, it can rapidly lead to a fatality if left unmanaged and will require prompt treatment in situ if developed during spaceflight. Chest tube insertion is the definitive treatment for pneumothorax, but it requires a high level of skill and frequent practice for safe use. Physician astronauts may struggle to maintain this skill on medium- and long-duration exploration-class missions, and it is inappropriate for pure just-in-time learning or skill refreshment paradigms. This paper proposes semi-automating tool insertion to reduce the risk of complications in austere environments and describes preliminary experiments providing initial validation of an intelligent prototype system. Specifically, we showcase and analyse motion and force recordings from a sensorized percutaneous access needle inserted repeatedly into an ex vivo tissue phantom, along with relevant physiological data simultaneously recorded from the operator. When coupled with minimal just-in-time training and/or augmented reality guidance, the proposed system may enable non-expert operators to safely perform emergency chest tube insertion without the use of ground resources. • System design of a desktop testbed that facilitates data-driven event labelling. • Use of a lightweight robot enables semi-automation during simulated surgical tasks. • Needle-tissue interaction forces are useful for surgical semi-automation. • Robotics and wearables allow for human-in-the-loop system performance monitoring. [ABSTRACT FROM AUTHOR]

Robot-assisted airway intubation application needs high accuracy in locating targets and organs. Two vital landmarks, nostrils and glottis, can be detected during the intubation to accommodate the stages of nasal intubation. Automated landmark detection can provide accurate localization and quantitative evaluation. The Detection Transformer (DeTR) leads object detectors to a new paradigm with long-range dependence. However, current DeTR requires long iterations to converge, and does not perform well in detecting small objects. This paper proposes a transformer-based landmark detection solution with deformable DeTR and the semantic-aligned-matching module for detecting landmarks in robot-assisted intubation. The semantics aligner can effectively align the semantics of object queries and image features in the same embedding space using the most discriminative features. To evaluate the performance of our solution, we utilize a publicly accessible glottis dataset and automatically annotate a nostril detection dataset. The experimental results demonstrate our competitive performance in detection accuracy. Our code can be accessible at https://github.com/ConorLTH/airway-intubation_landmarks-detection. [ABSTRACT FROM AUTHOR]

• Estimation of three-dimensional respiratory displacements of chest and abdomen using wearable inertial sensors. • Estimation of thoracoabdominal asynchrony during labored breathing using Lissajous curves and a cross correlation phase angle calculation method. • Nonlinear observer design and rigorous analysis to ensure global exponential stability of estimation algorithms. • Compensation of tilt and roll motions during breathing for accurate computation of respiratory displacements.. This paper develops and evaluates a wearable sensor-based system for the estimation of three-dimensional thoracoabdominal displacements and the detection of respiratory asynchrony between chest and abdomen. Such estimation is useful for a number of respiratory diagnosis applications, including detection of paradoxical breathing, quantification of tidal volume, and decision-support for initiation of, or weaning from, mechanical ventilation. The use of inertial sensors on the body to estimate respiratory displacements is challenging due to the tilting of the body that occurs with breathing, causing continuous changes in the gravity component at the same frequency as the breathing frequency. A method to estimate the front-to-back and side-to-side tilt angles is developed using a nonlinear observer. Due to the complex multivariable nonlinear measurement functions involved, a switched gain nonlinear observer is found to be necessary. The global stability of the observer is analyzed using Lyapunov analysis. Respiratory asynchrony is evaluated using Lissajous curves and a cross correlation phase angle calculation method. Example experimental results are presented using data from three subjects at various breathing frequencies, tidal volumes, and inspiratory resistances. Displacement estimates are found to be typically within ± 1 mm compared to a gold standard reference for most data sets. Phase angles are found to increase monotonically with inspiratory resistive or elastic loading. [ABSTRACT FROM AUTHOR]

• The method automatically classifies the breathing phases within a lung sound recording, which can help clinicians when using lung sound recordings to diagnose or monitor disease. • The method was tested on a large, heterogeneous data set of real lung sounds (1263 recordings) recorded from 125 subjects (with and without respiratory disease) at different chest locations including recordings with both crackles and wheeze. • The method showed very good and well-balanced performance, with sensitivity (92.51 (12.93) %), positive predictive value (91.09 (15.42) %), and F1-score (90.78 (12.37) %); where results are shown as mean (standard deviation)). • The method utilizes fast, time domain signal processing steps that make it computationally efficient compared to recently published deep learning methods. This paper presents a new method for automatic identification of the inspiratory and expiratory breathing phases in lung sound recordings. Adventitious lung sounds (wheezes and crackles), superimposed on the breath sounds, are generally an early indication of the disease, and their timing in the breathing cycle (early/mid/late inspiratory or expiratory) has clinical significance for monitoring or diagnosing disease. Therefore, the identification of the phases of the breathing cycle is an essential step for clinical interpretation of pulmonary auscultation. The proposed algorithm is designed to be robust in the presence of adventitious lung sounds or where the breath sounds may be noisy compared to healthy lung sounds. The algorithm uses the Savitzky & Golay (SG) filter to estimate the second derivative of the lung sound signal then calculates its normalized absolute value. A threshold value is used to clip any large amplitude peaks and, following low-pas filtering, the breathing phases are visible in the plotted signal. A rule-based approach to locating peaks and troughs is then used to identify inspirations and expirations. The performance of the method is evaluated using four different datasets: (a) a longitudinal dataset recorded from 19 subjects with a diagnosis of idiopathic pulmonary fibrosis (IPF), (b) a cross-sectional dataset recorded from 55 subjects who were referred for high-resolution computed tomography (HRCT) scan of the chest for various clinical indications, (c) a longitudinal dataset recorded from 10 healthy subjects, and (d) an open access lung sounds dataset containing recordings from 41 subjects with wheeze (9 with chronic obstructive pulmonary fibrosis and 32 with asthma). On average for inspiratory phase identification the algorithm had a sensitivity of (mean (standard deviation)) 92.84 (12.88)%, positive predictive value of 90.64 (15.96)%, and F 1 -score of 90.67 (12.53)%. For identification of the expiratory phase, the algorithm had an average sensitivity of 92.19 (13.44)%, an average positive predictive value of 91.55 (15.23)%, and an average F 1 -score of 90.89 (12.45)%. The method shows good potential for automatic identification of breathing phases in recorded lung sounds. [ABSTRACT FROM AUTHOR]

Patients undergoing bone marrow transplantation or chemotherapy for cancer are profoundly immunosuppressed. They are at risk for both endogenous and exogenous infections and require enhanced protection from infection while in hospital. The aim of this narrative review was to determine the optimal design features of bone marrow transplant (BMT) units for reducing infection risk in these vulnerable patients. A literature search was performed on PubMed and other databases for documents published between January 2000 and October 2021. Keywords were: bone marrow transplant unit OR hematopoietic stem cell transplant unit OR haematology unit OR haemato-oncology unit AND design OR design guidelines OR design criteria OR ventilation specification OR HEPA filtration OR water outbreaks OR water system design. Guidelines and other papers pertaining to BMT unit design are discussed. Key design features identified from the literature to reduce infection risks include high efficiency particulate air filtration, positive-pressure ventilation, sufficient air changes and sealed rooms. The evidence for each of these parameters and other findings are discussed. We found no guidelines specific to water quality and control in BMT units. Guidelines on the various components of design were found, but no comprehensive guidance documents addressing all relevant aspects, such as ventilation, water, and other design features, were found. Literary publications and policy documents were combined and summarised to highlight key design features aimed at reducing infection risk in this vulnerable patient group. We propose the development of international guidance for the design of BMT units encompassing all components. [ABSTRACT FROM AUTHOR]

Highlights • Development of a heat exchanger semi-empirical model accounting for frost formation. • Experimental validation of the HX model in partially frost regime. • Frost control strategies numerically implemented and compared. • Strategies lead to trade-offs between ventilation quality and energy consumption. Abstract This paper tackles the issue of frost formation in air-to-air heat recovery devices dedicated to single room ventilation by means of both numerical simulations and experimental approaches. In such heat exchangers, it is commonly known that the formation of a frost layer on the surface generates an additional thermal resistance and a flow section reduction, which leads to an overall degradation of the overall unit performance. This paper proposes a three-zone model, considering a dry, a wet and a frost zone, by determining the location of moving boundaries. Each zone is handled independently and the relative proportion of each zone is determined by means of the exchanger wall temperature. Besides this frost model, a defrost model is also envisaged. Once validated with experimental data collected on a U-flow-type heat exchanger, the developed model is used to implement different strategies to reduce or prevent frost formation in the exchanger. Based on three different criteria, these strategies are compared with each other to evaluate their benefits and drawbacks. The criteria give information on the energy efficiency of the ventilation, on the air renewal quality and on the pressure balance between the inside and the outside of the building. [ABSTRACT FROM AUTHOR]

Abstract The ventilation effect in different places in the teaching building is different. The aim of this paper is to study the relative ventilation relationship of the rooms in "line" type middle school teaching building. Taking Xiamen in the subtropical region as a typical city, a number of parameters such as the inside and outside corridors, different room sizes and different ventilation angles were set as variables, using the CFD simulation method. Combined and separated effects of the defined parameters on natural ventilation performance are evaluated using the ratio of air-age area as criteria. The result shows that the "line" type teaching building with outside corridor ventilation is 35.55% better than the inside corridor. In addition, the ventilation in large room is 30.84% better than that in small rooms. In 0°–35° wind direction, the closer the room to the incident wind the better in ventilation, but in a certain angle range of 59°–90°, the room farther away from the incident wind, the better in ventilation. The best wind angle of "line" teaching building ventilation is 305°–55°. The research results in this paper can help architects to design buildings more scientifically and reasonably. Highlights • "Line" type teaching building should adopt outside corridor form, it is conducive to ventilation in subtropical area. • The outside corridor ventilation effect is 35.55% better than the inside corridor. • Large room is suitable for laboratory and small room is suitable for temporary lounge cause ventilation feature. • The ventilation effect of the classrooms is related to the wind direction and classroom positions. [ABSTRACT FROM AUTHOR]

Highlight • New on/off controller for residential applications validated using minute-level field data. • On/off controller improves the HVAC accuracy around 19% in terms of NMBE. • On/off cycling makes the operation and associated energy use more realistic. Abstract Heating, ventilation, and air-conditioning (HVAC) systems are sized using design conditions, conditions that occur only a small percentage of time each year. As a result, HVAC systems frequently operate at part-load conditions since their capacity is larger than necessary except in the most extreme weather conditions. Most HVAC systems for residential and small commercial buildings in the U.S. use on/off controls, however, most energy modeling software tools do not simulate the on/off nature of this type of HVAC controls. This paper presents the development and validation of an on/off controller for residential applications in EnergyPlus using a custom EMS (energy management system). This controller is validated using minute-level field data collected for a house located in Sacramento, California with simulated occupancy and internal loads. The results obtained from EnergyPlus with and without the use of the developed on/off controller are also compared. The application of the developed on/off controller improves the HVAC energy use results accuracy around 19% in terms of the Normalized Mean Bias Error (NMBE) at the one-minute level compared to the results without the application of the on/off controller. It also makes the nature of operation and associated energy use signal of the HVAC system more realistic in terms of the on/off nature of the residential direct expansion coils. Furthermore, in this paper, the accuracy improvement of the results dominated by the internal loads is investigated by applying the one-minute schedule compared to the usual hourly schedules for the internal thermal loads. [ABSTRACT FROM AUTHOR]

Highlights • Photovoltaic powered ventilation system for parked electric car. • Solar photovoltaic car roof charging system for parked car's ventilation. • Photovoltaic powered electro-mechanical system for climate control of parked electric car. Abstract This paper explores the use of electric car roof mounted photovoltaic (PV) powered ventilation for cabin heat management/ventilation. A fully-functional Renault Zoe electric car has been used for performance evaluation of parked electric car ventilation directly powered by PV. This work has been part of a research project of testing electric cars in the urban environment and it has been conducted at the Edinburgh Napier University's Transport Research Institute. In this work, parked electric car ventilation has been reported, when roof-mounted PV modules were used to operate DC powered fans for ventilation. It has been found that the DC motor-fan selection for removing the hot air from cabin space is of important (i.e. operating characteristics of motor-fan have been very close to the maximum power points locus of the PV modules at different solar insolation). The electric car cabin temperature models with reference to solar radiation have been presented and it will be useful for knowing the parked car cabin temperature variations and designing the car roof mounted PV powered ventilation system. In this paper, performance evaluation of parked electric car's cabin heat management is presented and analysed. Results from this work will be helpful for designing electric car ventilation system (operating at parking time), when powered by vehicle roof integrated PV modules. [ABSTRACT FROM AUTHOR]

Increasing use of volatile renewable energy sources causes challenges in balancing supply and demand. Therefore, demand-side flexibility has rising importance for system operators and balancing authorities. Flexibility management methods are needed to integrate loads like ventilation systems of different buildings (e.g., residential and commercial) into flexibility service. However, the available methods described in research papers require further development for implementation in practice. Heating and cooling systems have received much attention from researchers, but the potential of ventilation systems has been left out of focus. Therefore, this paper provides a complete set of novel flexibility management methods for ventilation systems created from an aggregator's viewpoint. The flexibility is quantified through capacity (e.i. the amount of power consumption that can be altered), forced ventilation rate duration, and the tendered price for the service. The proposed methods were tested on a building model constructed and simulated in IDA ICE. The data processing and flexibility management methods were applied in MATLAB. Two types of ventilation systems with different sensor configurations were considered: constant and variable air volume. Forced ventilation rate duration is calculated using energy and mass balance analysis where the root means squared error was 10 to 33 min, depending on the system type, measured parameter, and sensor location. The flexibility service pricing model was tested on the 2022 years' manual frequency restoration reserve (mFRR) activation and balance energy market data. [ABSTRACT FROM AUTHOR]

• Climate change and urban setting impact energy use of buildings. • Energy use is higher due to overlapping effect of climate change and microclimate. • A method is proposed to account for future and urban environment in thermal simulation. • The results can assist in sizing passive ventilation systems. Urban settings and climate change both impact on energy use and thermal comfort inside buildings. This paper first presents a study of changes in energy demand in residential buildings considering the overlapping effect of climate change and urban heat island intensity in two European locations; Cadiz (Spain) and London (United Kingdom), representing temperate and hot European climates and moderate and dense urban settings. Future-urban weather files were generated and simulations were run considering energy demand and indoor thermal comfort. In hot climate regions such as the one of Cadiz, future climate will increase the cooling demand and the additional impact of the UHI leads to a further increase of up to +28% of total energy demand compared to the current climate without considering urban effects. Future-urban weather conditions will be detrimental also for buildings in London, where the annual energy demand is predicted to increase by up to the 16% if future climate and urban effects are included. This is due to a higher increase in cooling demand compared to the reduction for the heating need. The paper also presents a method to take into account microclimatic conditions in naturally ventilated buildings, especially the effect of wind variations around the building which impacts natural ventilation rates. Air and surface temperature and wind speeds were studied using ENVImet and the resulting microclimatic conditions were used as inputs to the EnergyPlus Airflow Network model for the calculation of the building ventilation rates. It was found that ventilation rates are reduced (in comparison to meteorological weather files) and this reduction impacts negatively on internal operative temperatures. A thermal comfort analysis was carried out indicating that the selection of a suitable weather file and microclimatic conditions is essential for more accurate predictions of internal thermal comfort and will assist in the sizing of passive and active systems to avoid overheating. [ABSTRACT FROM AUTHOR]

Highlights • A dynamic model is established for PVT-TEV system. • The system heat fresh air by PVT coupled with thermoelectric ventilator system. • Sensitivity analysis is implemented for model parameters optimization. • The average COP of the PVT-TEV system can reach 13.85. Abstract This paper presents a dynamic model for a photovoltaic thermal-compound thermoelectric ventilator (PVT-TEV) system, in which photovoltaic thermal (PVT) collector generates electricity in winter and simultaneously preheats the fresh air to achieve comprehensive utilization of solar energy. The preheated fresh air is further heated by the thermoelectric ventilator (TEV) and then pumped into the indoor room. The PVT-TEV system has the function of the sunshade, power generation, waste heat recovery and fresh air supply for buildings. The model is validated by the data collected from PVT-TEV system under real climate conditions. The results show that the simulated value is in good agreement with the experimental value. The performance of the PVT-TEV system under different working condition is also analyzed by using the model. Increasing the fresh air mass flow rate can improve the electrical and heating performance of PVT-TEV system. However, the total coefficient of performance (COP total) of PVT-TEV system does not grow when the fresh airflow rate rises from 93 m3/h to 123 m3/h and 153 m3/h due to the increase of fan power. The heat gain of the TEV system and the fresh air outlet temperature of the PVT-TEV increase with the working current. The growth of indoor temperature can improve the performance of PVT-TEV system. The model of PVT-TEV system proposed in this paper provides a foundation for the structural design and annual performance optimization of PVT-TEV system. [ABSTRACT FROM AUTHOR]

Highlights • This paper uses building structural attributes such as shapes of buildings, relative compactness(RC), glazing area(GA), roof area(RA), surface area(SA), wall area(WA), orientation(OR), overall height(OH) and glazing area distribution(GAD) for prediction of heating and cooling load. • The paper explores the data set and features to get insights with feature correlation, mutual information their association strengths etc and their relation with heating and cooling load. • The paper proposes novel group of methods based on emerging machine learning method extreme learning machine(ELM) which has shallows architecture. • The paper proposes novel method based on ELM variant online sequential extreme learning machine(OSELM) for heating and cooling load prediction in online and adaptive environment. This model also helps when data is trained in chunk by chunk fashion. • The paper demonstrates several models based on combination of learning mode, activation function and features sets and compare their results with existing work extensively. Abstract In the present day environment, smart buildings require optimization of energy consumption through monitoring, consumption prediction and making policy decisions accordingly. Attributes related to building design and structure play a vital role in heating load(HL) and cooling load(CL) of the building which directly affects the energy performance of the buildings. For prediction of HL and CL, emerging machine learning approaches can help in improving accuracy and efficiency in real time. This paper provides improvements in energy load assessment of the buildings. It is the first is the in-depth study and analysis of design and structural attributes and their correlation with HL and CL, the novel methods based on ELM and its variants online sequential ELM(OSELM) to predict HL and CL. This study also proposes OSELM based online/real-time prediction when data is coming in stream The total 24 models have been developed including 12 models based on ELM and 12 models based on OSELM with different feature sets and activation functions. Models have been compared on the basis of accuracy, computational performance and efficiency with few existing models. The experimental results show that the proposed models learn better and outperform other popular machine learning approaches such as the artificial neural network(ANNs), support vector machine(SVM), radial basis function network(RBFN), random forest(RF) and existing work in the energy and building domain. [ABSTRACT FROM AUTHOR]

Abstract The current safety regulations and its correlative specifications of the coal industry ignore the problem of malfunction. To solve the issue completely, an optimized location model based on the methane sensor is proposed in this paper. The proposed model is not only economic but also reliable for a sensor of methane. In the procedure of establishing the optimized model, this paper selects the nodes of mine ventilation network as candidates, and the points specified by Mine regulations and specifications. A three-stage hybrid Pareto ant colony algorithm (HPACA) based on the column reduction, tabu search (TS) and Pareto ant colony algorithm (HPACA) is also designed. Finally, practical application of the proposed model is displayed with an example of the mine ventilation network.The computation results show that the HPACA algorithm can achieve the optimal solution or the approximate optimal solution of the location model quickly and effectively. [ABSTRACT FROM AUTHOR]

This paper examines the provision of demand-side ancillary services using building thermodynamics and heating ventilation and air-conditioning (HVAC) systems. In particular, we consider the secondary frequency control service where the load has to declare a power capacity and a nominal power at the beginning of the regulation period and then in real-time track the received regulation signal around its declared nominal power. A hierarchical control scheme is proposed in this paper. The local building controllers at the lowest level track the temperature setpoints received from the thermal flexibility controller which maximizes the flexibility of building’s thermal consumption. At the highest level, the electrical flexibility controller controls the HVAC system while maximizing the flexibility provided to the grid. The two flexibility control layers are based on robust optimization methods. A control oriented model of a typical HVAC system is developed, and simulations are carried out to demonstrate the efficacy of the proposed approach. Results show that extra flexibility may be attained by exploiting the coefficient of performance (COP) of the chiller. Furthermore, occupant comfort increases as a consequence of providing ancillary services. [ABSTRACT FROM AUTHOR]

In an effort to minimise electricity consumption and greenhouse gases emissions, the heating, ventilation and air-conditioning sector has focused its attention on developing alternative solutions to electrically-driven vapour-compression cooling. Liquid desiccant air-conditioning systems represent an energy-efficient and more environmentally friendly alternative technology for dehumidification and cooling, particularly in those cases with high latent loads to maintain indoor air quality and comfort conditions. This technology is considered particularly efficient in hot and humid climates. As a matter of fact, the choice of the desiccant solution influences the overall performance of the system. The current paper reviews the working principle of liquid desiccant systems, focusing on the thermodynamic properties of the desiccant solutions and describes an evaluation of the reference thermodynamic properties of different desiccant solutions to identify which thermodynamic, physical, transport property influences the liquid desiccant process and to what extent. The comparison of these thermodynamic properties for the commonly used desiccants is conducted to estimate which fluid could perform most favourably in the system. The economic factors and the effect of different applications and climatic conditions on the system performance are also described. The paper is intended to be the first step in the evaluation of alternative desiccant fluids able to overcome the problems related to the use of the common desiccant solutions, such as crystallization and corrosion to metals. Ionic liquids seem a promising alternative working fluid in liquid desiccant air-conditioning systems and their characteristics and cost are discussed. [ABSTRACT FROM AUTHOR]

This paper proposes an initial proof-of-concept validation for a method that estimates the respiratory effort during pressure support ventilation, based solely on the signals provided by a standard commercial ventilator. The study is carried out on a test bench with an Active Servo Lung 5000 mechanical simulator. The asymptotic behavior of the respiratory mechanics during expiration is exploited to analyze its identifiability (the fact that two sets of respiratory mechanics parameters necessarily generate distinct signals). Furthermore, we propose a method of estimation of the patient's respiratory muscle pressure, based on the degree of smoothness of a signal constructed from the airway pressure and flow measurements. The proposed method was validated on a commercial ventilator, under a wide range of respiratory mechanics parameters and respiratory efforts. Our approach provides a non-invasive estimation of the respiratory effort, which allows for accurately detecting over- and under-assistance. Compared to existing muscle pressure estimation methods, our approach clarifies the conditions under which the respiratory effort of a patient can be estimated and offers a simple way to compute it in real time, without using invasive devices or occlusion-based techniques. [ABSTRACT FROM AUTHOR]

The radiation dose of workers in underground uranium mines mainly comes from radon and radon progeny. To ensure a healthy and safe work environment, it is necessary and urgent to optimize the design of ventilation systems. As such, based on the simplified radon diffusion-advection migration model of the rocks, this paper proposes 1) two methods for determining the radon exhalation rate modified by pressure drop, 2) three methods for calculating radon activity concentration of single-branch, and 3) the novel adjustment algorithm and solving procedures for calculating and adjusting the radon activity concentration in ventilation networks by modifying the radon exhalation rate, demonstrated on a specific ventilation network in a simulated underground uranium mine with calculation and analysis via MATLAB. The results show that 1) the radon exhalation rate of different branches can be modified by their pressure drop, and 2) the proposed method can be used to reveal the influences of different ventilation methods and fan pressures on the radon activity concentration in the ventilation network and the radon release rate to the atmosphere. • Two methods to modify the radon exhalation rate of roadway-surrounding rocks by pressure drop were developed. • Three methods were proposed for reasonably calculating the radon activity concentration in single branch. • The novel adjustment algorithm and solving procedures for analyzing radon-containing ventilation networks were established. • The ventilation methods and its operating parameters of radon reduction were evaluated and optimized. [ABSTRACT FROM AUTHOR]

This paper introduces a novel approach for controlling the operational ventilation in complex road tunnels. Basically, the control structure is feed-forward with an adaptive logic. The feed-forward part includes the static optimization which uses the mathematical model of airflow dynamics. The adaptive logic is based on the recursive least squares with exponential forgetting, which compensates deviations between the mathematical model and real measured data, and thus provides a feedback. During the standard operation of road tunnels, requirements to maintain indoor air quality (IAQ) and protect the surrounding area of a tunnel from pollution, are necessary. Moreover, reducing electricity costs is desirable, as the ventilation in road tunnels forms a significant part of electricity costs. The control scheme has been validated through the long-term evaluation of operation in the Blanka tunnel complex in Prague, Czech Republic, which is the largest city tunnel in Central Europe. The experimental validation of the proposed control scheme is the main contribution of the paper. [ABSTRACT FROM AUTHOR]

In order to obtain satisfactory effect of air conditioning and ventilation, the floor–supply displacement ventilation has widely applied in many civil buildings. Swirl diffusers mounted on the floor are widely used to provide fresh air into the occupied zone in the floor–supply displacement ventilation system. This paper studied the air distribution performance of swirl diffuser by 2D-PIV (particle image velocimetry). The experiment was implemented in a full-scale room to achieve reliable data of swirl diffusers. Flow visualizations have been carried out to determine the shape of the swirl jet. The whole velocity field was measured by 2D-PIV system, which is very useful to analyze air distribution above the swirl diffuser. With the aid of the flow visualizations and PIV test technology, the macro and micro structure of the air flow above the swirl diffuser is specified in more detail. Moreover, the centerline velocity decay coefficient (K value) and entrainment ratio were obtained. The research work of this paper provides detailed experimental data of air flow above the swirl diffuser, which provide the reference for selection of air terminal devices and a basis for follow-up numerical simulation study. [ABSTRACT FROM AUTHOR]

Improved ventilation in an urban residential neighborhood is a determinant for better energy efficiency and air quality of the neighborhood. This is particularly important for the real estimates recently developed in many cities in China, as these neighborhoods are built with high density. In this paper, we consider in an idealized neighborhood with two categories of packaging building densities ( λ p ) of 0.25 and 0.44, which respectively represent medium and compact urban development. For each packaging density, the frontal area density of arrays is varied from 0.125 to 0.5 through adding building blocks and reducing building size simultaneously. Computational fluid dynamics simulations are carried out to predict the wind flow through the building arrays by the use of renormalization group (RNG) k - ε turbulence model. Our predictions are validated by comparing with experimental data. Numerical results reveal that ventilation rate could be greatly enhanced when a low level of packaging building density is maintained. The momentum exchange rate at the canopy roof level is effectively strengthened when the frontal area density decreases, together with a reduction of ventilation in the urban canopy layer (UCL). Additionally, a linear relationship is found between the UCL ventilation rate and the momentum exchange rate at the urban canopy roof level. For a constant packaging density, reducing frontal area density improves the city block ventilation by enhancing the air exchange rate at the roof level rather than increasing horizontal drag. This paper also illustrates a practical strategy in optimum neighborhood building layout design to minimize the pollutant level. [ABSTRACT FROM AUTHOR]

The oily wastewater through union station was between 40-70 ℃. The sewage was injected to the ground or direct discharge after treatment and it resulted in heat waste in union station. In the meaning time, there were many energy demands in union station, such as building heating, the crude oil heating, the liquid heating and so on. Paper summarized the current status of heat waste in oilfield and absorption heat pump technology. The paper took the absorption heat pump heating project in Kenxi Oilfield Station as an example. The paper introduced the program design. And the energy consumption was compared before and after the transformation. The energy-saving efficiency (ζ) is up to 63% and the COP of lithium bromide unit was 1.54. It proved the absorption heat pump technology had distinct advantages of energy-saving in the union station. [ABSTRACT FROM AUTHOR]

This paper investigates the overall energy performance of a ventilated amorphous silicon photovoltaic (a-Si PV) window under different operation strategies in the hot-summer and cold-winter zone. A validated numerical model based on EnergyPlus was developed and utilized to simulate the thermal, power and overall energy performance of the a-Si PV window. With the integrated numerical model, the effects of air gap depth and ventilation modes on the electricity generation, energy consumption of the air conditioning system and building net energy consumption was investigated. The results indicate that the natural ventilation mode of the ventilated a-Si PV window performs best in summer while the non-ventilation mode is the best choice in winter in the hot-summer and cold-winter zone, Changsha. With the increasing of air gap depth, the net electricity use decreases first and then increases. Based on the simulation results, the optimal structure designing and ventilation operation strategy are recommended. The findings of this paper could provide guidelines for optimizing the structure and the operation strategy of the ventilated a-Si PV windows in hot-summer and cold-winter zone in China. [ABSTRACT FROM AUTHOR]

At present, dynamic simulation and analysis on building thermal environment and energy consumption achieved by computer software become a reality. However, it is found that defined gaps exist between simulation and on-site measurement. To explore the gaps, this paper takes typical air-conditioned university dormitories located in Chongqing as a case study. Simultaneously, the gaps are explored with a DeST-h building energy simulation model and on-site measurement. Indicators including indoor temperature, relative humidity and air conditioning energy consumption under different setting temperature are simulated and measured. Then, a comparison between simulation results and measured data is explored as well as the cause of these gaps. This paper studies thermal environment and energy consumption by combining on-site measurement and numerical simulation, and the conclusion is that the gaps can from occupant behaviour and physical parameters of the indoor and outdoor environment, which provides a reference for thermal environment of the dormitory and building simulation. [ABSTRACT FROM AUTHOR]

Inverter is one of the most important equipment in photovoltaic power plant. Ventilation cooling can affect inverter efficiency, and then affect the photovoltaic power plant reliability. This paper analyses several different ventilation schemes for integrated inverter, and compares two CFD models which are ventilation with and without hood and duct using simulation software “ANSYS FLUENT”. The CFD simulation shows that hood and duct can improve the cooling effect. The paper shows that inverter ventilation with hood and duct can reduce the energy cost and ensures the photovoltaic power plant reliability, this ventilation scheme is recommend for inverter room ventilation. [ABSTRACT FROM AUTHOR]

In order to clarify the influence of outdoor inhalable particulate matter on the interior of existing public office buildings in Cold area, this paper uses the method of weight method and instantaneous detection to measure the indoor and outdoor inhalable particulate matter concentration of two existing office buildings in Shenyang in summer. The changes of daily average, instantaneous concentration and I/O ratio of PM 2.5 and PM 10 in the indoor and outdoor are analyzed, and the influence of outdoor particulate matter on the concentration of indoor and outdoor inhalable particulate matter in two buildings was analyzed by analyzing the correlation of indoor and outdoor concentration change and regression. This paper provides a reference for the study of the different airtight buildings on the barrier properties of outdoor inhalable particulate matter and the improvement of the indoor environment quality. [ABSTRACT FROM AUTHOR]

Ultra-low-energy buildings in China are still in the early stage of development. In the guide documents of the 13th plan of five-year national development published by Science and Technology Ministry, an energy consumption limit of 15kWh/m2 for heating, cooling and ventilation throughout the year was pointed out for residential buildings in hot summer and cold winter region. In this paper, current situation of winter heating in Shanghai was investigated, including analysis of heating energy consumption of more than 40,000 households, a large number of questionnaires about heating status, and the actual indoor heating environment monitoring. This paper also investigated the indoor ventilation environment under real living conditions, taking a typical residence in Shanghai as the research subject via continuous field measurements. The indoor CO2 concentration, air temperature and relative humidity were monitored and two behavior-related parameters, the electricity consumption of air conditioner and the open/closed state of the window/door were recorded from summer to spring. Based on the investigation, the questionnaires and the monitored data for winter heating, heating strategies in winter for residential buildings in Shanghai will be discussed, from the perspective of gap analysis. [ABSTRACT FROM AUTHOR]

As one of the complex underlying surfaces, the water body improved the local thermal climate in the surrounding area especially on water vapor diffusion and temperature. Therefore, this paper, taking the water effect and factor analysis as the research object, based on the CFD method, key factors were analyzed which influencing thermal and humidity environment in the waterfront areas. The factors mainly discussed in this paper are building type, building floor area ratio, embankment height, distance from water body, and landscaping. Each factor includes five levels. The results indicated that the influence scales of thermal and humidity environment were highly dependent on the geometry of ventilation gallery in the residential areas of the waterfront. The results also indicated that the temperature in area with the low plot ratio and large ventilation gallery was more easily affected by the waterbody. [ABSTRACT FROM AUTHOR]

• This paper presents a comprehensive review of cross ventilation research in buildings. • The advantages and disadvantages of different research methods are compared. • The ventilation models of cross ventilation are reviewed. • The influencing parameters of cross ventilation are summarized. • The future perspectives of cross ventilation research and practical applications are proposed. There is a growing body of literature that recognizes that natural ventilation plays a vital role in indoor air quality, thermal comfort and building energy consumption. This paper systematically reviews the previously published research of the most efficient and typical natural ventilation type - cross ventilation, aiming to present the main research topics in contemporary research and provide an agenda for future studies. The methodologies, airflow pattern, ventilation models and influencing parameters of cross ventilation were comprehensively summarized and discussed. The chained analysis and data-driven methods are the potential approaches to study cross ventilation more efficiently. The comparisons of different ventilation models of cross ventilation help to better understand the basic mechanisms that drive the cross ventilation airflow. [ABSTRACT FROM AUTHOR]

This paper investigates the theoretical capacity of the Swiss peri-urban dwelling stock to meet energy efficiency requirements through incremental scenarios. The notion of “typical dwelling” allows the assessment of housing energy efficiency at the country scale. The “2000-W society” concept and federal policies provide the assessment framework of the daily-mobility and housing operational energy demand along with embodied energies of the dwelling stock. The typical dwellings’ current performance for several territorial entities highlight the extent of the challenge the peri-urban housing stock is facing today. Therefore, the paper investigates which conditions would allow the peri-urban typical dwelling to meet “2000-W society” intermediary targets. Eight incremental scenarios present theoretical improvements of mobility and housing. They assume an evolution of social practices and individual behaviours, as well as the development of improved technologies. Results show a drastic reduction of primary non-renewable energy (PNRE) demand and greenhouse gas (GHG) emissions for both mobility and dwelling-related consumption. The main findings are that the current MINERGIE-A label is sufficient to build energy efficient buildings, but the current mobility practices remain very far from targets. An optimization of trips and a broader recourse to low carbon conveyances are required to reduce the overall environmental footprint. [ABSTRACT FROM AUTHOR]

The paper deals with an influence of the ventilation system to the tunnel tube parts according to the traffic intensity. Simulations have been made by the PLC based tunnel simulator TuSim and the tools MATLAB and Simulink. The connection between MATLAB and TuSim has been made by free OPC server. The aim of this paper is to demonstrate dependence between base tunnel inputs like traffic intensity, lighting, atmospheric condition, air and car velocity and output pollutions. The obtained model is used to predict the output pollution values to the future. [ABSTRACT FROM AUTHOR]

Computer fire modelling and design fire scenarios are traditionally used in the tunnel design process to challenge tunnel systems, e.g. smoke ventilation, evacuation routes and strategy, and the exposure of structural members. In general, any such fire scenario should be reasonably severe, however, not unrealistically, which may lead to unnecessary over-designing and cost increase. This approach is commonly referred to as the worst-case design fire approach. The objective of the paper is to analyze the impact of uncertainties associated with input data and design fire selection on the representativeness of the design fire scenario. Firstly, the design fire scenario specifications are mapped and uncertainties relating to input data identified and quantified. Subsequently, a risk-based design fire selection approach is introduced taking into account the objective of the analysis: life safety or property protection. The paper is concluded with recommendations regarding the significance of selected input parameters, given analysis objectives, and the possibilities of their uncertainty treatment. [ABSTRACT FROM AUTHOR]

Concerning the building environment HVAC facilities, even if a great effort has been made in developing components and systems with high nominal efficiencies, less attention has been paid to the problem of system maintenance. The main objective of the thermoeconomic diagnosis is to detect possible anomalies and their location inside a component of the energy system. The second objective, and indeed the one to be achieved in this paper, is indicated as inverse problem. It is associated with the quantification of the effects of anomalies in terms of thermoeconomic quantities. Its rigorous application in building thermal installations has some difficulties relating to the strong interrelation between the different components and the fact that energy supply facilities are continuously changing with time. The way to deal with dynamic circumstances is thoroughly explored in this article. Likewise, this paper’s main goal is to demonstrate an application of two thermoeconomic diagnosis methodologies in the building sector, one based on the malfunction and dysfunction analysis and the other one based on the characteristic curves of the components. The results obtained allow us to point out the advantages and limitations of both methodologies as well as to combine them and then develop a more reliable diagnosis. [ABSTRACT FROM AUTHOR]

HVAC systems in buildings are composed of many subcomponents which consume energy in huge amounts. In recent years, energy consumption becomes very important aspect due to the lack of energy resources and environmental reasons. In terms of energy consumption, the components of HVAC systems account for large portion of total energy used in buildings. Therefore optimization of energy consumption in HVAC applications is an essential requirement in terms of thermodynamic and economic point of views. Besides, the efforts for decreasing energy consumption turn into economic recovery. It also provides benefits for human health and cleaner environment. In this paper, as originality, thermodynamic and economic analyses of an existing social and cultural building which has a heating and cooling area of 8852 m 2 are presented by comparing of a conventional HVAC and a VRF system. A novel contribution is given to the open literature by comparing two systems with actual data measured from the existing system. The other originality is to apply and test a VRF system to a complex-structured building. This study is a rare one which contains insulation, heating and cooling accounts of a building together. In this paper, VRF system is modelled to the existing building for the comparison of the conventional HVAC system. Both systems have been compared in terms of heating and cooling capacity, initial, operation and maintenance costs. It is found that the VRF system is more economic and efficient such that the VRF system is found to have 44% cost profit when compared with the conventional HVAC system. [ABSTRACT FROM AUTHOR]

A sleeping person is naturally immobile in a relatively small space. Hence, task\ambient air conditioning (TAC) can be best applied to a sleeping environment because of its proven performances in energy saving. However, when using previously developed the TAC systems for sleeping environment applications, cold draft was a serious issue and could hardly be avoided due to a high air velocity and a low air temperature inside an occupied zone. Therefore, in the experimental study reported in this paper, a radiation-based TAC (R-TAC) system has been developed, and its performances experimentally evaluated. In this paper, firstly, an experimental setup for a prototype R-TAC system, and experimental conditions and methods are reported. This is followed by presenting experimental results on the thermal comfort and ventilation performance. Finally, the issues of condensation risk when using the proposed R-TAC system are discussed. The study results presented in this paper have shown that the use of the R-TAC system could not only result in better thermal comfort and ventilation performances, but also effectively resolve the cold draft problem. In addition, the potential problem of potential condensation on a surface may be resolved by raising the panel surface temperature, or using a lower fresh air supply humidity. [ABSTRACT FROM AUTHOR]

This paper investigates the potential for incorporation of human commercial building design modelling into the pig production industry. During the last decades pig building design has relied heavily on building manufacturers compared to human commercial buildings that regulate standards to improve the sustainability of the building. Thus, the aim of this paper was to gain a greater understanding of the design requirements for sustainable forms of pig housing, which could potentially improve the welfare of the pig and promote greater resource use efficiency. Part of an existing mechanically ventilated UK pig production building, which represents three adjacent fully-slatted units each capable of holding approximately 292 pigs and measuring approximately 18 m x 14m, was used as a basis to create a dynamic thermal model of the building. The model takes into account the possibility of future rises in environmental temperature and the effect of this climate change on building performance and pig growth, feed efficiency and welfare. The results of the model showed that as the finishing pigs increased in size they have the potential to be subject to increasingly poor indoor air quality, during the winter months. The model also shows that improving the thermal properties of the building not only helps with reducing the amount of time that the pigs could potentially spend at extreme low temperatures, by approximately 1115 h (46 days), but can also help with reducing the number of hours the pigs spend above 26 °C during the summer months, by approximately 8 h. [ABSTRACT FROM AUTHOR]

In this paper the authors have set off from a critical approach in order to evaluate the CO 2 emission in a lecture hall (amphitheater) with a high number of occupants – 62 -, in order to determine the moment when it is required for the ventilation systems to intervene in the provision of air exchanges necessary to assure the hygienic conditions. The notion of stress used in this context refers to the continuous and degrading action of the CO 2 emissions against the occupants, we named the CO 2 emission external agent, and the increase of CO 2 emission will lead to the decrease of the efficiency of occupants activity inside the amphitheatre. The CO 2 measurements were made in the amphitheatre on a group of students, and it helped to evaluate the phenomenon and the mathematical apparatus confirmed the application of the theory of reliability stress in the studied problem. We hope that this approach will contribute to the establishment of some practices referring to the control and management of the functioning of ventilation systems in buildings with a significant number of occupiers and will contribute to the design of a device to command and control the functioning of the ventilation installation in concordance with the CO 2 emissions on the basis of the theory presented in this paper. [ABSTRACT FROM AUTHOR]

The paper presents a numerical solution to the unsteady form of the Navier-Stokes (N-S) equations along with the heat transfer equation. The problem of mass transfer with the energy transfer is very common in engineering, for instance, in designing ventilation systems or in founding. Solving the Navier-Stokes equations causes many numerical problems regardless of the chosen discretization method. What is more, numerical methods of solving the N-S equations are characterized by the significant time of calculations. The finite element method is often used when solving heat transfer equations. However, problems arise when it is used for solving the Navier-Stokes equations. They are related, for example, to the LBB condition (Ladyzhenskaya-Babuska-Breezi). In the paper, we have used the stabilized finite element method (FEM) form to solve the N-S equations. It is characterized by the ease of implementation and it does not have a negative influence on the efficiency of calculations. It also makes it possible to bypass the LBB condition. Integration over the time has been done with the help of widely known one-step theta scheme. The paper presents the result, which allows for the quality assessment of the obtained solution with the use of the aforementioned methods. To find the solution, a computer implementation of the presented mathematical problems has been created. On the basis of the obtained results, it is possible to state that the application of stabilization for FEM in the relation to the Navier-Stokes equations is an effective way to find the numerical solution. The authors of this paper are planning to further develop the software to apply it to simulations connected with the problems in the foundry process. [ABSTRACT FROM AUTHOR]

This paper presents the designing aspects and first experimental characterization of an adaptable Smart Modular Heat Recovery Unit (SMHRU) developed under the scope of the E2VENT Project. This SMHRU is being designed as a part of an adaptable renovation module for the retrofitting of multi-storey residential building from the 60 's, 70 's across Europe that embeds the SMHRU and an energy storage system based on a phase change material. This heat recovery unit will be adjustable to be integrated into the ventilated façade cavity, and able to recover heat from ventilation air, preheating the ventilation air in winter and precooling it in summer. This will allow an efficient combination of consumption reduction and acceptable air indoor quality. The first part of the paper presents designing considerations and thermal stationary analysis of the heat recovery unit, which is based on experimental correlations obtained for air-to-air compact offset-strip-fin plate heat exchangers. Secondly CFD analysis of the distributor of the SMHRU is presented. Finally prototype first performance estimation based on experimental results is presented. [ABSTRACT FROM AUTHOR]

This paper presents the basic methodologies used for Natural Smoke and Heat Ventilation Systems design under wind conditions, along with chosen numerical tools such as Computational Fluid Dynamics method and evacuation modelling as their supplement. First, results of comparison of different natural ventilation systems a series of transient CFD simulations are shown, illustrating potential problems in the system design with traditional approach. Later in the paper, authors focus on complete analysis of fire related phenomena in wind conditions, for a real historical shopping mall in Warsaw with vertical natural smoke ventilators. All of the steps of the analysis are described, together with some practical remarks. The reference analysis were carried in ANSYS Fluent CFD model, followed by evacuation study with building Exodus software. [ABSTRACT FROM AUTHOR]

Split Air Conditioner(AC) is a very popular cooling system not only for residential spaces but also commercial spaces.. Typically the split AC units are installed without adding any supply of outside air. While the supply of outside air is unregulated for residential spaces, the commercial spaces do have a ventilation requirement. The elimination of outside air supply is usually justified by a myth that the space is leaky enough that the infiltration can provide the ventilation requirement. This study aims at debunking the myth by presenting measurement data on the infiltration rate for air conditioned spaces. The measurement method used in this study is the tracer gas method with the CO2 is used as the tracer gas. This paper focuses at the development of an affordable instrument. The primary component of the instrument is the CO2 sensor that will trace the concentration of CO2 in the room. This paper shows how the components are assembled, tested and calibrated. The final product is about four times cheaper than the instrument available in the market. This paper also presents one measurement result that shows a very low infiltration rate for a space equipped with a split AC unit. [ABSTRACT FROM AUTHOR]

The former research of UHIis lack of universal operation and guide significance due to the obvious regional characteristics. This paper studied the spatial forming mechanism of UHI and planning mitigation countermeasures both theoretically and practically, and proved part of theory by taking Xi’an-Xianyang new district as an example. By analyzing the spatial forming mechanism from two scales, that is urban and community, we put forward planning mitigation countermeasures to different spatial scales. And then in case study, the paper analyzes the characteristics of Xi’an-Xianyang new district UHI in two scales, which to prove and deepen the former discussion. [ABSTRACT FROM AUTHOR]

The work in this paper involves the investigation of an office room in cooling mode ventilated by a 4-way cassette air-conditioner, which is increasingly being installed in Eastern China. A comparison of the 4-way cassette AC is made against a typical wall-mounted mixing ventilation system based on ADPI calculations as well as difference in air temperature and velocity. The results in this paper, which are carried out by computational fluid dynamics (CFD) simulation, indicate that a superior air distribution performance is achieved by the 4-way cassette AC when compared to the wall-mounted system. The results also show potentials for energy saving using the 4-way cassette AC. [ABSTRACT FROM AUTHOR]

This paper presents validation of the neural network model for predicting airtightness of residential and non-residential units. Proposed model developed in previous research utilizes a neural network in prediction of airtightness and it is obtained based on in situ measurements at 58 units in Croatia. Model applicability earlier was tested by independent validation through 20 additional measurements in Croatia and on 5 measurements in Serbia. This paper presents validation of neural network model for predicting airtightness of residential and non-residential units on database formed beyond the regional area. Database used for model validation in this paper consists of 20 residential and non-residential units from Poland with building construction technology similar to Croatian ones. Comparison of the results obtained by measurements and prediction model indicates that the model gives consistent results on the validation data set with similar building construction technology and demonstrates that model is not locally conditioned. [ABSTRACT FROM AUTHOR]

Spirometer is used as a major diagnostic tool for obstructive airway diseases and a monitoring tool for therapy response and disease staging over time. It is a sophisticated medical device employed to quantify flow and volume of air exhaled by a subject during a specific testing period. The essential metrics obtained from the spirometry test, play a crucial role in enabling healthcare professionals to thoroughly evaluate the respiratory health and condition of the individual under examination. Several spirometer measurements including Forced Vital Capacity (FVC) and Forced Expiratory Volume (FEV) serve as guidelines for diagnosis and prognosis of Chronic Obstructive Pulmonary Diseases (COPD) and asthma. However, user errors caused by different reasons, including improper handling of the equipment and poor performance during the maneuvers of the expiratory airflow, end up in incorrect treatment directions. To ensure accurate results, spirometry tests traditionally require the presence of a skilled professional to identify and address these errors promptly. A novel machine learning approach is proposed in this paper to automatically identify four such user errors based on Volume-Time and Flow-Volume graphs. By detecting specific errors and providing immediate feedback to patients, reliability and accuracy of spirometry results will be improved and the need for trained professionals will be reduced. The implementation facilitates the widespread adoption of spirometry, particularly in low-resource telemedicine settings. This work implements a binary classification model distinguishing between normal and error test samples, achieving a prediction accuracy of 93%. Additionally, a 4-way classification model is presented for identifying individual error sub-types, demonstrating a prediction accuracy of 94%. • Errors: Early Terminus, Extra Breath, Excessive Extrapolated Volume, SubMaximal Blast • Flattening and concatenation of 2 CNN Pipelines, one each for FV and VT graph inputs • Stratified 5-fold CV on categorical cross entropy loss and leaky ReLU activation unit • Error detection model - 93% accuracy and error classification model - 94% accuracy [ABSTRACT FROM AUTHOR]

Retrofitting the design of a ductwork system is often a critical aspect when renovating a centralized air distribution system. However, the existing approaches rely on the rules of thumb due to the absence of a standardized guideline for the design retrofitting process. Consequently, design engineers face costly and time-consuming challenges in generating retrofitted designs, particularly when dealing with the complexities of reusing the existing ductwork system. Although their design output may achieve functionality, it is not necessarily optimal in terms of cost and performance. To overcome these challenges, this paper proposes a simulation-based ductwork design strategy that utilizes metaheuristic optimization techniques to generate optimized ductwork designs for retrofits. The proposed method offers an automated solution for generating optimized ductwork configurations (i.e., layout and sizes). It strategically maximizes the reuse of existing ductwork components while simultaneously fulfilling the design performance criteria desired by the system and minimizing its life cycle cost. A case study was conducted to present the effectiveness of the developed method in retrofitting the ductwork design for a multi-story school building. This study involved a comparison between the design solution generated by the proposed method and the design solution generated through a conventional retrofitting design approach. The results from the proposed design retrofitting method showed a 17 % lower LCC and an approximately equally well-balanced design. These findings indicate the method's promising potential to contribute to the HVAC industry by providing an effective simulation-based method for automatically optimizing ductwork designs for retrofits. [ABSTRACT FROM AUTHOR]