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In this work, we investigate the influence of ZnO nanoparticles on the performance of paper-based humidity sensors. The sensors were developed on standard, commercial printing paper with laser-patterned gold interdigitated electrodes (IDE) and ZnO nanoparticles spin-coated by various sol-gels. Blank devices were used as reference sensors in an effort to elucidate the role of ZnO and the dependence of the device performance on the concentration of the sol-gels and the number of spin-coated layers. Resistive measurements were conducted at room temperature to evaluate the devices’ response on known relative humidity levels. Relatively fast rise and response times were observed even at room temperature, while all devices tested did not require refreshing procedures. The deposition of ZnO was found to affect the sensor response, resulting in reduced sensor signal, due to the blocking of water diffusion in the porous paper material. [ABSTRACT FROM AUTHOR]

Abstract: Mold deterioration of historical library materials in archives and libraries is a frequent and complex phenomenon that may have important economic and cultural consequences. Compactus shelving is one of the systems utilised for the conservation of library materials, because it allows for a more efficient use of space and protection against dust deposition. However, in the last ten years there have been many reports on single species mould infections within Compactus shelves in spite of conventional control of environmental temperature and humidity to recommended standards. Contamination was commonly characterized by white spots of mycelium, measuring 0.5–1.0 cm in diameter and observed on volume binding, especially those of leather, parchment or textile. Until now, the identification of the causal agent at species level has not been reported since attempts to grow it on media for subsequent identification were unsuccessful. Using a range of sampling techniques, including adhesive tape and nitrocellulose membrane, and a combination of conventional culturing methods, direct microscopic observations and molecular methods, we have for the first time identified to species level the fungus causing infections inside Compactus shelves. [Copyright &y& Elsevier]

One of the buzz words in current research depends for a weather forecast is the atmospheric temperature, and this value may change at any time. Predicting air temperature exactly is necessary since it is particularly important for various communities and events. In today's world of massive amounts of data and unforeseen data fluctuations, long-short term memory (LSTM), a sort of neural network method, is becoming more and more popular. The present work employed a sequence to sequence LSTM autoencoder to forecast Indian weather patterns. The prediction model was trained using historical data obtained from the Khordha district administration. The proposed method primarily emphasizes two phases of the procedure. The present study involves an examination of a proposed model, wherein a comparison is made between four distinct variants of LSTM techniques: vanilla LSTM, stacked LSTM, bidirectional LSTM, and convLSTM. The objective of this analysis is to predict temperature patterns. Additionally, this paper utilizes an LSTM autoencoder model to forecast the temperature for the subsequent two-year period in the Khordha district of Odisha, India. The experimental investigation demonstrates that the utilization of Stacking encoder-decoders with bidirectional LSTM cells leads to a notable enhancement in the accuracy of the model, resulting in maximum efficacy. A notably lower Mean Absolute Error (MAE) result suggests that the 9-layer stacked autoencoder model has superior performance in predicting both the minimum and maximum temperature. [ABSTRACT FROM AUTHOR]

• The outdoor air relative humidity also has an impact on the threshold temperature of frost accumulation. • Under certain conditions, higher efficiency of heat recovery may be safer in terms of frost risk. • The largest ' frost ' accumulation area is formed for the middle values of the return air relative humidity (in analyzed case RH 2 i =38.5 %). In this paper, a process of frost accumulation inside the non-hygroscopic rotary heat exchanger depending on operating conditions is investigated. The study was based on the results of the numerical simulations conducted in the original computer program. The analysis considers both the threshold conditions of frost accumulation and the conditions of frost layer growth. For this purpose, three indicators related to frost accumulation were distinguished: a frost accumulation limit temperature, a surface of the matrix covered with the accumulated frost layer, a maximum thickness of the accumulated frost layer. The analyzes assessed the influence of operating parameters on these indicators, focusing on the return air relative humidity. It was revealed that the highest values of this parameter cause the greater thickness of the frost layer. However, the largest ' frost ' accumulation area was created in the range of average return air relative humidity values – in the analyzed cases it was RH 2 i =38.5 %. The paper also includes a detailed analysis of the threshold temperature of frost accumulation. These limits of outdoor air temperature were determined for a wide range of operating parameters' values: both airstream relative humidity and nominal temperature effectiveness. Additionally, eight probable configurations of active heat and mass transfer areas within rotary heat exchanger channels were revealed, which are related to the initiation of frost accumulation. Consequently, the locations of the initial ' frost ' accumulation area were predicted. It was also found that the greatest impact on the frost accumulation threshold temperature has the return air relative humidity RH 2 i , although this influence is not unequivocal. The most unfavorable conditions regarding nominal temperature effectiveness in terms of frost accumulation are also unclear. In some cases, it was even demonstrated that an increase in the effectiveness can eliminate the ' frost ' accumulation area. [ABSTRACT FROM AUTHOR]

A composite thermo-hygroscopic material with loose surface, neat and single pore size distribution for lightweight envelope structure was hereby prepared in this paper by compounding inorganic minerals with polymer materials using the sol–gel method. The moisture storage capacity, isothermal humidity control characteristics of this material were studied through static isothermal humidity controlling performance experiments. Besides, its performance in terms of the air temperature, relative humidity, moisture content in the light-weight assembly building (movable panel house), laying thickness, and laying area on the indoor air parameters were studied under the action of outdoor climate conditions and indoor periodic humidity load using the effective humidity penetration thickness model. It was found that under winter conditions, the laying of CHPCMs can moderate the effects of outdoor temperature and humidity load changes on indoor temperature, relative humidity and moisture content, and effectively delay the fluctuation of indoor air parameters. CHPCM exhibits an optimal laying thickness value, and the deviation from the optimal thickness value can weaken its ability to regulate indoor environmental parameters. The average air relative humidity of the naturally ventilated room with a laying area of 24 m2 is about 4.6 % lower than the average air relative humidity with a laying area of 12 m2. [ABSTRACT FROM AUTHOR]

• The 1D model of an open heat storage reactor containing zeolite 13X is presented. • Model validation is based on simultaneous mass and heat transfer measurements. • Three adsorption isotherm models (Langmuir, DA, modified BET) are compared. • The modified BET model provides the best results (> DA > Langmuir). • Proper characterization of the sorbent (isotherms, heat of sorption) is essential. Efficient modeling of thermochemical heat storage reactors is required to predict their performance in various operating conditions and optimize their design. Such modeling necessitates an accurate description of the properties of storage materials, which is still challenging to this day. This paper specifically investigates the influence of the choice of the sorption isotherm model. To this aim, the Langmuir, Dubinin-Astakhov (DA) and modified Brunauer-Emmet-Teller (BET) isotherm models are studied. The 1D model of an open fixed bed reactor based on the hydration and dehydration of zeolite 13X is presented. The model couples heat and mass transfer and uses the linear driving force approximation. Experimental investigations are also performed to characterize the sorption equilibrium of the material, its adsorption kinetics at the reactor scale and the resulting heat storage performance. The model is validated simultaneously on the basis of mass and of heat transfer measurements (i.e., breakthrough and temperature curves). The BET isotherm is shown to be the most relevant for the description of water adsorption on zeolite 13X because it considers multilayer adsorption. It fits the experimental isotherm best. At the reactor scale, the modified BET model also provides the best results, closely followed by the DA model. Still, for consistent predictions, the characterization of the chosen sorbent (i.e., the experimental data used to correlate the isotherm model or the heat of sorption) is of utmost importance and the initial water loading must be adequately specified. [ABSTRACT FROM AUTHOR]

• Made a small-area analysis of greenspace exposure and heat-mortality associations. • Examined which type and location of greenspace matter most in heat health risk reduction. • Unlike grassland, forests yielded significant health benefits under heat. • Greenspace, especially forests, within a 1 km radius of residents matter most. • More apparent effects were observed for greenspace nearby than area-level exposure. While vegetation type, population density and proximity to greenspaces have been linked to human health, what type and location of greenspace matter most have remained unclear. In this context, there are question marks over investment-style metrics. This paper aims at establishing what vegetation type may matter most in modifying heat-mortality associations, and what the optimal buffer distances of total and specific types of greenspace exposure associated with reduced heat-related mortality risks are. We conducted small-area analyses using daily mortality data for 286 Territory Planning Units (TPUs) across Hong Kong and 1 × 1 km gridded air temperature data for the summer months (2005–2018). Using a case time series design, we examined effect modifications of total and specific types of greenspaces, as well as population-weighted exposure at varying buffer distances (200–4000 m). We tested the significance of effect modifications by comparing relative risks (RRs) between the lowest and highest quartiles of each greenspace exposure metric; and explored the strength of effect modifications by calculating the ratio of RRs. Forests, unlike grasslands, showed significant effect modifications on heat-mortality associations, with RRs rising from 0.98 (95 %CI: 0.92,1.05) to 1.06 (1.03, 1.10) for the highest to lowest quartiles (p -value = 0.037) The optimal distances associated with the most apparent effects were around 1 km for population-weighted exposure, with the ratio of RRs being 1.424 (1.038,1.954) for NDVI, 1.191 (1.004,1.413) for total greenspace, and 1.227 (1.024,1.470) for forests. A marked difference was observed in terms of the paired area-level and optimal distance-based exposure to total greenspace and forests under extreme heat (p -values < 0.05). Our findings suggest that greenspace, particularly nearby forests, may significantly mitigate heat-related mortality risks. [ABSTRACT FROM AUTHOR]

The high temperature of PV panels during power generation not only reduces their efficiency but also leads to increased heat transfer to the room. The impact of using PV panels on the indoor thermal environment should not be overlooked. A novel roof structure is proposed in this paper, which is composed of PV panels, phase change materials (PCMs) and ventilation layer from top to bottom. The thermal performance of PV-PCM- ventilation roof room is compared with that of PV roof room and PV-PCM roof room under active and passive conditions respectively. Results show that under passive conditions: Compared to PV roof, the PV-PCM-ventilation roof internal surface temperature fluctuation decreases by 44.12%, the correlation coefficient between the back surface temperature of PV panel and outdoor air temperature decreases from 0.79 to 0.69, and the correlation coefficient with solar radiation decreases from 0.66 to 0.60. Compared to PV-PCM roof, the back surface temperature of the PV panel decreases by 3.31 °C during the day. Under active conditions, when the set temperature is 26 °C and 28 °C, the energy consumption of the PV-PCM-ventilation roof room decreases by 15.61% compared to the PV roof room. In summary, the new roof demonstrates good insulation and energy-saving performance. [ABSTRACT FROM AUTHOR]

Air-cooled chillers are extensively employed to meet cooling demand in commercial and tertiary sectors. To enhance their performance during part-load operation, variable-speed drives have been integrated into compressors and condenser fans. In existing systems, condenser fans are either operated at a fixed speed or modulated to maintain a predetermined condensing pressure or temperature difference between the refrigerant and outdoor air. In the search for increased efficiency, it is worth investigating innovative control strategies aimed at minimizing energy consumption. A preliminary mapping of chiller performance at different fan speeds, loads, and operating conditions is required to achieve this goal. In this respect, this paper investigates the operation of air-cooled chillers equipped with variable-speed condenser fans, both in the case of constant- and variable-speed compressors. An ad hoc matrix test is adopted to cover appropriate ranges conditions, in terms of load and outdoor air temperatures. Performance maps are developed for a 50-kW c chiller using a 1-D simulator. As the main findings, it may be stated that (i) in the case of the variable-speed chiller, the energy efficiency ratio increases almost linearly with fan speed, resulting in an 8.8% increase when increasing the speed from the nominal to the maximum; (ii) in the case of constant-speed chillers, the system exhibits a different behavior with the cooling capacity and the energy efficiency ratio increasing with the fan speed between 380 and 980 rpm and then decreasing (slightly or sharply, at full and part load respectively) with fan speed between 980 and 1280 rpm, and a percentage increase of EER in the range 7.8–45% is observed. Also, the sensitivity of such results to the system design is investigated, analyzing a chiller equipped with a larger condenser that resulted in achieving minimum energy consumption at an optimal 980 rpm fan speed. Finally, for a constant-speed chiller serving an office building in the Mediterranean, the proposed fan control strategy could yield an electricity saving of up to 12.1% compared to the base case, confirming the potential for energy savings through optimized and system-tailored management of condenser fan speed. • The effect of variable-speed fans on the performance of air-cooled chillers is investigated. • Maps are developed for chillers with both variable-speed and constant-speed compressors. • Fan speed significantly influences the cooling capacity of constant-speed chillers. • In variable-speed chillers, it is advisable to always run the condenser fan at high speed. • The enhanced fan strategy enables 12.1% energy savings for a chiller in an office building. [ABSTRACT FROM AUTHOR]

Abstract Winter road maintenance is costly but it is necessary in order to keep roads accessible and safe during winter. Current winter road maintenance methods use 600,000 tons of salt annually, in the Nordic countries. The salt ends up in the environment along the roads and results in environmental challenges. Alternative winter maintenance methods that use heat instead of salt are in use today. However, those systems are designed to use high temperature of about 20–35 °C. This paper presents a numerical model for designing low temperature (4–8 °C) hydronic heated pavements (HHP). The model is validated against an experimental setup and different control strategies are evaluated. The validation indicated that the developed model can predict the behavior of the HHP with a root mean square error (RMSE) <1.4 °C for surface temperatures and <0.4 °C for the return fluid. In this paper the model is used with two different control strategies. A basic strategy controlling the system based on air temperature and one strategy based on dew point temperature. With dew point regulation the energy consumption can be reduced by 62%. However, the energy consumption is still in the range of 125–180kWh/m2 for the location of Östersund, Sweden. We found that the HHP system can utilize low temperature sources like waste energy or geothermal energy that is freely available. By using renewable energy for winter road maintenance, the environmental impact from winter road maintenance can be reduced. Highligths • Dewpoint control reduces the energy demand for heated pavements. • Low supply temperatures of 2-8 °C makes it possible to use renewable energy sources. • Presents a 3-D numerical model including the fluid domain for heated pavements. • Snow ploughing strategies affects the energy usage more a low temperature. [ABSTRACT FROM AUTHOR]

Highlights • This paper presents a dam health monitoring model based on long-term air temperature. • Radial basis function networks are adopted to mine the temperature effect on the dam displacement. • The proposed dam health monitoring model is verified on a real concrete gravity dam. • Results show that the proposed approach can obtain better results than models using harmonic sinusoidal functions. Abstract Dam health monitoring is usually achieved by using the hydrostatic-season-time model that simulates the temperature effect through harmonic sinusoidal functions. The model is convenient, but does not take into account the effect of temperature variations in different years on dam response. This paper presents a dam health monitoring model using long-term air temperature for thermal effect simulation. In the model, harmonic sinusoidal functions are replaced by long-term air temperature to simulate the temperature effect on the dam response. The machine learning technique RBFN is adopted to mine the temperature effect from long-term air temperature series. The proposed dam health monitoring model was verified using monitoring data of a real concrete gravity dam. Results show that the nonlinear RBFN model utilizing long-term air temperature achieves better results than the model using harmonic sinusoidal functions. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the correlations between the continuously monitored gamma dose rate (GDR) and meteorological parameters, including precipitation, air temperature, relative humidity, air pressure, wind direction, and wind speed, were analyzed by using one year of the hourly dataset from a monitoring system with ten stations. The correlation coefficients are varied by the range of each meteorological parameter. Precipitation would enhance the GDR up to 84%, which is highly related to precipitation intensity and ground type. Strong and positive correlation between the GDR and light precipitation was identified, while the correlation was reduced with increasing of precipitation. Air temperature could cause a fluctuation of the average GDR within the range 1.8–5.3 nGy h−1, and different correlation characteristics were indicated for low and high air temperature. The GDR was positively correlated with relative humidity, though relative humidity is inversely correlated with air temperature. Correlations between the GDR and air pressure were mainly negative. Diurnal variations between the GDR and the air temperature, relative humidity, and air pressure were also analyzed. The wind played an important role also in the fluctuation of the GDR with the GDR difference up to 2.00 nGy h−1 averaged from the sixteen wind-directions. Lower GDR can be found in the direction of prevailing wind because of the dilution effect of the radon progenies in the surface air. In this paper, some exploratory interpretation of physical influence mechanisms of meteorological parameters on the GDR was also presented, which suggests further work should be carried out to explore the variation and correlation principle. Highlights • The GDR at ten monitoring stations is statistically analyzed. • The quantitative analysis for correlation between GDR and the meteorological parameters is presented. • Different characteristics of GDR at ground station and roof station are identified. • The impact mechanisms from the meteorological parameters are explanatorily discussed. [ABSTRACT FROM AUTHOR]

Abstract This paper demonstrates the thermodynamic performance analysis of direct evaporative cooling system by increasing sides of cooling media. In this paper, a different configuration of cooling media has been developed for determining the behaviour pattern of the direct evaporative cooling system based on performance characteristics using Aspen fibers media. The effect of inlet air temperature, humidity and mass flow rate of air has been discussed in detail by using the different configuration of cooling media. The result indicates that the saturation efficiency is approximately same for entire developed top flow and ordinary lateral flow configurations excluding triangle top flow configuration. The highest saturation efficiency were observed for triangle configuration 97% for case-I. Maximum saturation efficiency of the triangular configuration of an evaporative cooling system was found to be 97%, 88%, nil and 89% for case-I, case-II, case-III and case-IV respectively, over ordinary and other top flow DEC system. [ABSTRACT FROM AUTHOR]

High-speed railway tunnels in the cold region, whose numbers are increasing, are widely exposed to the threat of frost damage caused by extremely negative temperatures. The operation of high-speed trains has made this problem even more pronounced. But there are fewer studies focusing on the dynamic changes in temperature during train operation. In this paper, the air thermodynamic behavior of trains passing through a tunnel and its consequences were investigated with the help of the CFD method. In numerical simulations, conditions of different natural airflows, different train speeds, different blockage ratios, as well as two trains intersecting in the tunnel were involved. The following valuable results were obtained. In cold environments, train-induced pressure wave effects will affect the air thermodynamic behavior, but the overall trend in air temperature is mainly influenced by the heat transfer between cold and warm air. The high-speed train will lead to massive cold air being carried into the tunnel and some warm air inside being pushed out. Heat transfer between cold and warm air will cause a significant decrease in tunnel air temperature. This air thermodynamic behavior is particularly prominent in the case of large blockage ratios. When there are same-direction natural airflows, they will be coupled with train-induced airflows, causing a greater decrease in tunnel air temperature. In contrast, opposite-direction natural airflows can reduce the negative effects of the train. Taking the case of opposite-direction natural airflow velocity of 5 m/s as an example, the temperature changes of the three cross-sections are only 16.7 %, 14.8 %, and 42.1 % of those in the case of no natural airflow. Whatever the direction of natural airflows, coupling effects between them and train-induced airflows will be more significant as the natural airflow speed increases. Greater train speed means more cold air entering the tunnel and stronger heat transfer between cold and warm air, causing a more significant temperature decrease. When two trains intersect through the tunnel, airflows caused by them will be coupled. As a result, only a little air enters the tunnel from the entrance and exit, and the heat transfer between air with different temperatures is weak. In this case, the air temperature doesn't decrease but slightly increases as the air is compressed. [ABSTRACT FROM AUTHOR]

Air–water heat transfer is a crucial method for achieving stable air supply in cleanrooms. This paper models the heat transfer process in the specific scenarios, enabling estimation of the heat exchangers' outlet temperature response based on variations in the inlet temperature. Additionally, considering practical requirements, we derive the outlet performance in scenarios involving multiple heat exchangers in series. An experimental setup was established to evaluate the time-domain and frequency-domain responses of the heat exchanger outlet airflow under different flow rates and numbers of heat exchangers. The spectral distribution fits of the outlet air consistently exceeded 82%. Furthermore, precise estimation error at the m ° C level was achieved, with the average error ratio of the outlet air approaching 10%. The experimental results validated the model's accuracy and provided guidance for achieving high-precision air supply, particularly in maintaining a temperature-stable output airflow through constant-temperature water and air–water heat exchange processes. • Developing the air–water cross-flow heat transfer process model. • Deriving the output performance under series heat exchangers. • Achieving accurate heat exchanger outlet temperature estimates. • Reference for realizing high-precision supply air temperature in cleanrooms. [ABSTRACT FROM AUTHOR]

The Human Development Index (HDI) is one of the most widely used composite indicators of socio-economic development. However, the HDI is at the cross-roads. In order to retain its flagship role in the development arena, many scholars have called from the HDI to reinvent itself by adding sustainability dimensions. The aim of this paper is to introduce the Sustainable Human Development Index (SHDI), based on Multidimensional Synthesis of Indicators (MSI) – a new class of indexes that can be used for monitoring Sustainable Human Development (SHD). The approach we propose aims to address two primary issues regarding the HDI. The first issue involves the integration into the SHDI of two important sustainability-related dimensions that are missing in the HDI; namely, the environment and freedom (defined here in terms of political rights and civil liberties). The second issue focuses on the method of aggregation using the new class of indexes proposed. We aim to expand on the three standard HDI dimensions while avoiding problems associated with the geometric mean that tends to collapse to zero. In doing so, we manage to retain the same theoretical intuitions of the post-2010 HDI approach, i.e. to penalize the heterogeneity of outcomes. Moreover, we rely on the flexibility of the MSI approach to develop another index, the Environmentally-centered Sustainable Human Development Index (ESHDI), which puts the environmental dimension at the core of the analysis. In the first part of the paper we introduce the theoretical debate on the multidimensionality of the HDI, and consider the two new dimensions of sustainability, as well as the MSI aggregation approach. In the second part, the SHDI and the ESHDI are introduced, tested through a simulation analysis, and are compared with the HDI geometric mean using 2013 data. The simulations and the results of the empirical analysis show how the new class of indexes provide a more flexible approach to the procedure of aggregation, especially when the number of dimensions increases and/or when there is the need to stress the importance of one or more dimensions. The introduction of the two environmental and freedom sustainability dimensions greatly increases the potential of the HDI to address the SHD paradigm by capturing two core issues for the humanity and its common future. [ABSTRACT FROM AUTHOR]

Refrigerators are a common appliance in developed and emerging economies around the world. These appliances consume significant energy globally and improving their efficiency is an important aspect of future climate change mitigation. It is widely understood that the energy consumption of household refrigerating appliances is strongly influenced by room temperature and many analysts have identified ambient temperature as the most important factor in normal use. Room temperature has two main effects on the energy consumption of refrigerating appliances. Firstly, the temperature difference between the compartment and the room dictates the heat gain into the appliance through the wall insulation and door seals. A second effect is that a change in room temperature affects the condensing temperature. An increase in room temperature reduces overall refrigeration system efficiency by increasing the difference between the evaporating and condensing temperature. This paper examines laboratory data for 111 appliances where energy consumption is measured at four ambient temperatures from 10 °C to 40 °C. Field data for 235 appliances in homes is also examined. This is more complex to analyse, but it does provide useful information on underlying energy changes due to changes in room temperature during normal use. This paper determines the ratio of energy at 16–32 °C (energy conditions in IEC62552-3) and explores the shape of the energy curve at intermediate temperatures in order to develop a generalised energy curve as a function of temperature for the refrigerating appliances measured. The field data gave highly comparable shape data to that measured in the laboratory. The results provide a useful method to estimate the likely power consumption of different appliance types under a wide range of operating conditions, even where limited data is available. [ABSTRACT FROM AUTHOR]

Land Use and Land Cover (LULC) maps are vital prerequisites for weather prediction models. This study proposes a framework to generate LULC maps based on the U.S. Geological Survey (USGS) 24-category scheme using Google Earth Engine. To realize a precise LULC map, a fusion of pixel-based and object-based classification strategies was implemented using various machine learning techniques across different seasons. For this purpose, feature importance analysis was conducted on the top classifiers considering the dynamic (seasonal) behavior of LULC. The results showed that ensemble approaches such as Random Forest and Gradient Tree Boosting outperformed other algorithms. The results also demonstrated that the object-based approach had better performance due to the consideration of contextual features. Finally, the proposed fusion framework produced a LULC map with higher accuracy (overall accuracy = 94.92% and kappa coefficient = 94.19%). Furthermore, the performance of the generated LULC map was assessed by applying it to the Weather Research and Forecasting (WRF) model for downscaling wind speed and 2-m air temperature (T2). The assessment indicated that the generated LULC map effectively reflected real-world conditions, thereby impacting the estimation of wind speed and T2 fields by WRF. Statistical assessments demonstrated enhancements in RMSE by 0.02 °C, MAE by 1 °C, and Bias by 0.03 °C for T2. Additionally, there was an improvement of 0.06 m/s in MAE for wind speed. Consequently, the framework can be implemented to produce accurate and up-to-date high-resolution LULC maps in various geographical areas worldwide. The source codes corresponding to this research paper are available on GitHub via https://github.com/Mganjirad/GEE-LULC-WRF. • A framework was developed to create a LULC using GEE for WRF model. • Fusing seasonal features from object and pixel based methods improved LULC accuracy. • Ensemble ML algorthims, outperformed other models in classification accuracy. • The GEE-generated LULC map improved WRF accuracy for T2 and wind speed estimation. • The developed framework improves global LULC mapping and weather parameter accuracy. [ABSTRACT FROM AUTHOR]

Atmospheric particle matters which contribute the most to the haze weather in China have raised the public awareness in recent years. This paper collected the current research status of PM2.5 and the hourly data which were recorded from authoritative websites shows the outdoor concentration of PM2.5 and PM10 from July 2015 to December 2015 in Tangshan urban area. The indoor data recorded by dust monitor were compared with outdoor counterparts to analyze the variation and factors of indoor concentration of PM2.5. The results indicate the close correlation between the indoor and outdoor concentration of PM2.5 in Tangshan urban district in the paper. [ABSTRACT FROM AUTHOR]

The energy consumption of air conditioning system accounts for a significant proportion of the total energy consumed in data center. To reduce the energy consumption of the cooling system, an integrated system, which combines pumped refrigerant two-phase cycle (PRTC) with vapor compression cycle (VCC), is proposed in this paper. The impacts of input frequency and outdoor air temperature on the performances of PRTC, and that of the outdoor air temperature on the performances of VCC have been investigated. It was found that PRTC had higher EER than VCC, but its cooling capacity was limited by outdoor air temperature. In PRTC, the designed cooling capacity of 2500 W could be obtained when the outdoor air temperature was −3.0 °C. In addition, 80% and 50% of the designed cooling capacity can be obtained at ambient temperatures 3.2 °C and 12.0 °C, respectively. Besides, the feasibility of the system in different climate zones in China was demonstrated by analysis of the climate data in Harbin, Beijing, Wuhan, Guangzhou and Guiyang, respectively. Results indicated the proposed system had high feasibility in Harbin and Beijing. The results of this paper can provide valuable insights into the cooling system driven by both liquid refrigerant pump (LRP) and vapor compressor, targeting at reducing the cooling energy consumption and maximizing the economic efficiency of the cooling system in data center. [ABSTRACT FROM AUTHOR]

In this paper, a coordinated strategy of distributed model predictive control (DMPC) is proposed to accommodate Air Handling Unit (AHU) and Variable Air Volume boxes (VAV boxes) in a multi-zone HVAC (Heating Ventilation and Air Conditioning) system. A modified distributed model predictive control with equivalent local cooling cost and a total-air-mass-rate penalty term is implemented to local VAV boxes to regulate indoor temperature. The penalty term and AHU supply air temperature are updated in the upper coordinated layer to guarantee the total air mass rate within the limit and economic operation. In this framework, with the help of coordination from both DMPC and the upper layer, the operational cost from the HVAC system can be reduced. The effectiveness of the proposed scheme is proved by a numerical simulation. • A coordinated DMPC is proposed to accommodate equipment in multi-zone HVAC system. • A modified DMPC is implemented to regulate indoor temperature. • The coordinated layer is used to keep the total air mass rate within the limit. • The supply air temperature PID generates a suitable value for subsystems. [ABSTRACT FROM AUTHOR]

This paper is dedicated to creep buckling predictions. Thin walled cylinders having an aspect ratio of one are subjected to an uniform external pressure. The material is a special type of nickel which “creeps” at ambient temperature. The material parameters for the creep law are identified from experimental results. The creep failure experiments are described and corresponding failure times are given. The paper then compares three alternatives of finite element modeling of the experiments (3D Shell with integration through the thickness with a periodic or non periodic initial imperfection are compared with COMU quasi axi-symmetric imperfect shell element). These 3 modeling show consistent predictions. The simulation time is a hundred times faster with the COMU model. It is shown that the prediction of failure time of these experiments is extremely sensitive to the initial imperfection amplitude. The effect of creep law modeling is also important. Finally a parametric analysis on different types of cylinders is given: some general trends are proposed for this type of delicate predictions. [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 examines the local and non-local climatic effects of wetter arid areas of Northwestern China (ANWC) in summer using a fully coupled climate model. In response to soil moisture increase, the local air temperature significantly decreases, and precipitation increases in summer. The wetter ANWC results in a warmer and rainless climate over the Central part of North China Plain (CNCP). While the influence of increasing soil moisture on the Tibetan Plateau (TP) precipitation is negligible due to the high altitude. A cooler climate over ANWC leads to an abnormal descending motion occurring. Meanwhile, an anomalous high pressure and an abnormal anticyclonic circulation occurs in 500 hPa over the west of ANWC. Correspondingly, a huge anomalous cyclone circulation occurs over the northeastern part of China and Mongolia, which can hinder the northward movement of the East Asian summer Monsoon (EASM) and reduce the water vapor transport into Central China Plain. As a result, the weakened EASM thus leads to rainless over CNCP. As soil moisture increases over ANWC is stronger, the magnitudes of the influence on the atmospheric field become larger. This study highlights the wetter ANWC effect on local climate and provides more information about the mechanism of wetter ANWC remote effect on non-local climate. • This paper examines the local and non-local climatic effects of wetter arid areas of Northwestern China (ANWC) in summer using a fully coupled climate model. • It finds that the wetter ANWC can result in a warmer and rainless climate over the Central part of North China Plain (CNCP) through a complex atmospheric circulation response. • A cooler climate leads to an abnormal descending motion occurring over ANWC. • A huge anomalous cyclone circulation over the northeastern part of China and Mongolia can block the East Asian summer Monsoon northward and decrease the water vapor transport into Central China Plain. • This study highlights the wetter ANWC effect on local climate and provides more information about the mechanism of wetter ANWC remote effect on non-local climate. [ABSTRACT FROM AUTHOR]

By measuring practical temperature and performing questionnaire surveys, this paper investigates the energy consumption and existing indoor thermal condition in rural residential buildings during heating season in severe cold areas in northeast of China. Research is conducted on the characteristics of heating and energy consumption in rural residential buildings in severe cold areas from heating system such as Chinese “kangs”, rustic heaters, stoves and heated walls. The main results in the paper can be summarized as follows: (1) The remarkable characteristic of thermal environment in rural residential buildings is the uneven distribution of temperature both in one room and in different rooms; (2) Installation of insulation layers can effectively improve indoor thermal environment; (3) Income level of rural residents is the main factor that influences indoor thermal environment; (4) The main ways of heating are Chinese “kangs”, rustic heaters, stoves and heated walls in rural residential buildings in severe cold areas. These factors and laws obtained can influence the energy consumption in rural residential buildings in heating season in severe cold areas in northeast of China. [ABSTRACT FROM AUTHOR]

The paper considers the problems of improving the operational safety of the two-way tunnel subway under weather conditions characteristic of Russian megapolises. A significant difference is indicated between annually mean, monthly mean and extreme outdoor air temperatures affecting thermodynamic parameters of the intra-subway atmosphere in Russia and foreign countries having subways. Comparative characteristics are given for the factors determining temperature regimes of the subway lines with single-way and two-way tunnels in case conventional ventilation schemes are used. The paper also describes alternative ventilation schemes involving constructive elements widely used for venting motor-road tunnels. Based on specific initial data, calculations have been performed whose results characterize temperature distribution in running single-way and two-way tunnels vented by using the ventilation scheme comprising vent ducts and air recirculation. The efficiency of the two-way tunnel ventilation scheme comprising a ventilation duct and air recirculation has been justified. Mathematical simulation of the dynamics of smoke propagation in case of a fire in tunnels and at stations has been accomplished. Efficiency of the emergency ventilation scheme comprising a vent duct in smoke protection of the fire evacuation passages for people and in smoke removal has been proved. The paper presents such station complex layout solutions that, contrary to historical prototypes, imply integrating the station ventilation and smoke removal systems into the general structure of the station space-planning solutions so that they are in close vicinity of all the designed passenger flows with retention of the comfortable space necessary for passengers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Misuse of the Redlich–Peterson isotherm is widespread. • Errors are found in papers published in prominent journals. • Deficiencies encompass faulty mathematical forms, flawed linearized versions, incorrect parameter units. • Guidelines for avoiding pitfalls are provided. The Redlich–Peterson isotherm, a variant of the Sips isotherm, is widely used to describe the adsorption characteristics of water contaminants. Despite its popularity, this isotherm is susceptible to misuse and misinterpretation. In this article, we aim to bring to light the various deficiencies associated with the Redlich–Peterson equation, encompassing faulty mathematical formulations, unverified mechanistic interpretations, erroneous linearized versions, unnecessary parameter constraints, incorrect parameter units, inappropriate model comparisons, model misidentifications, and flawed thermodynamic calculations. These deficiencies often stem from a lack of mathematical expertise or a poor understanding of adsorption modeling, and occasionally, from egregious negligence. Our primary goal is to draw attention to these pitfalls and encourage researchers to steer clear of them. By providing guidance and shedding light on these issues, we aim to foster the judicious application of the Redlich–Peterson equation in the analysis and interpretation of adsorption equilibrium data. [ABSTRACT FROM AUTHOR]

• The effect of coolant preheating strategy on cold start performance is investigated. • One-dimensional model of fuel cell systems is established by AMESim software. • The accuracy of the model is verified by corresponding cold start experiments. • Air inlet temperature, air inlet flow rate, and heating power effects are clarified to improve the cold start performance. The rapid cold start capability of fuel cell vehicles in low-temperature environments is one of the key factors restricting their commercialization. Reasonable and effective strategies are crucial to improving the low-temperature cold start capability of fuel cell vehicles. In this paper, a cold start model of fuel cell system is established, and the model is verified based on the cold start experiment of a hybrid fuel cell vehicle. The necessity of the coolant preheating strategy in the cold start is analyzed, and the important role of the coolant preheating strategy in helping the fuel cell system to start quickly at -10°C and below is demonstrated. Furthermore, the effects of air inlet temperature, air inlet flow rate, and external heater power on the cold start performance are investigated. The results show that when the air inlet temperature rises from -13°C to 65°C, the start time is shortened from 279 s to 234 s (reduced by 16.13 %). And at low air inlet temperatures, the lower flow rate of air can significantly reduce the temperature difference and maintain uniformity of temperature inside the stack, while at a higher temperature, the higher air flow rate causes the temperature of the cell stack to rise rapidly. For heating power, the start time is shortened from 421 s to 126 s (reduced by 70.07 %) when the heating power is increased from 3 kW to 11 kW. However, it will cause a larger temperature difference between the inlet and outlet of the coolant, which is not conducive to the uniform distribution of the temperature inside the stack. Thus, the start time can be shortened by increasing the air inlet temperature, air inlet flow rate, and heating power with the consideration of the temperature difference that the stack can withstand. The model developed by this study provides an effective way to analyze the fuel cell system during cold start, which is useful for the development of control strategies in the future. [ABSTRACT FROM AUTHOR]

The energy crisis caused by climate change is the most significant challenge of the 21st century. Single-objective and multi-objective optimization studies for buildings often only consider the building itself, without considering the impacts of climate change. However, in the future, energy-efficient design and appropriate operating parameters will be crucial considerations in the face of global climate change. This paper aims to discuss the impact of climate change in the humid-hot region over the past 60 years on the energy consumption of office buildings and propose countermeasures. Firstly, the meteorological data of Guangzhou from 1960 to 2020 is statistically analyzed, and four typical meteorological years and corresponding air conditioning design days are established. Secondly, Energyplus is used to simulate the building's energy consumption, and the energy consumption factors are analyzed for sensitivity using jEplus. Finally, a multi-objective optimization is performed using jEPlus + EA with the Non-dominated Sorting Genetic Algorithm (NSGA-II). The results found that climate change led to a significant increase in the duration of high outdoor temperatures during summer. Specifically, the daily dry-bulb temperature for air conditioning design increased by 0.4–0.7 °C, and due to climate change, the energy consumption of the office building increased by about 4.6 %. The main factor affecting the cooling energy consumption in summer was the indoor cooling set point (8.29%–30%), infiltration air volume (1.0%–8.6%), fresh air volume (3.2%–16.06%), the glazing solar transmission rate (1.25%–9.0%), building orientation (0%–1.43%), and relatively small influence of envelope insulation performance. The operation scheme determined by multi-objective optimization can reduce the cooling energy consumption of the building by 10.6%–16.8%, which can mitigate the rise in energy consumption resulting from climate change to a greater extent. [Display omitted] • Discuss the impact of climate change over the past 60 years on the energy consumption of office buildings. • There was a significant increase in the duration of high outdoor temperatures during the summer. • Multi-objective optimization is performed using jEPlus + EA. • Climate change caused energy consumption to increase by about 4.6 %. • Optimal solutions can reduce the cooling energy consumption of the building by 10.6%–16.8%. [ABSTRACT FROM AUTHOR]

The conventional HVAC system for multi-area buildings includes both centralized and in-situ equipment to collectively regulate indoor air temperature to meet the preferences of its occupants. However, due to the limited capacity of the total supply air mass rate in centralized equipment, maintaining comfortable indoor air temperature for all areas can face conflicts. The first conflict arises between satisfying diverse preferences and limited global resources, while the second conflict is between centralized air supply and distributed regulation. In this paper, a distributed zone model predictive control (DZMPC) with priority conflict resolution is proposed for the multi-area HVAC systems. This strategy is composed of a zone parameter optimization with dynamic priority as a coordinated upper layer and a lower DZMPC layer. In the upper layer, a zone parameter optimization with priority is presented to coordinate sub-controllers by adjusting variable references' bounds for DZMPC, to solve the resource competition when it occurs. In the lower layer, model predictive control with zone control is formed to mitigate the tension of the shared resource. By integrating dual decomposition and Augmented Lagrange function to address global constraints, a distributed solvable control structure is formed. The resulting optimization can be solved using a distributed primal–dual algorithm. The effectiveness of the proposed scheme is proved by simulation examples. [ABSTRACT FROM AUTHOR]

During the years, adsorption has garnered considerable attention being one of the most cost-effective and efficient methods for separating contaminants out of liquid phase. A comprehensive understanding of adsorption mechanisms entails several crucial steps, including adsorbent characterization, batch and column adsorption tests, fitting of predefined kinetic and isotherm models, and meticulous thermodynamic analysis. These combined efforts serve to provide clarity and insights into the intricate workings of adsorption phenomena. However, the vast amount of literature published in the field each year is riddled with ill-considered model selections and incorrect parameter analyses. Therefore, the aim of this paper is to establish guidelines for the proper employment of these numerous kinetic, isotherm, and fixed-bed models in various applications. A thorough review has been undertaken, encompassing more than 45 kinetic models, 70 isotherm models, and 45 fixed bed models available hitherto, with their classification determined based on the adsorption mechanisms expounded within each of them. Moreover, five general approaches for modifying fixed-bed models were provided. The physical meanings, assumptions, and interconversion relationships of the models were discussed in detail, along with the information criterion used to evaluate their validity. In addition to commonly used activation energy and Gibbs energy analysis, the methods for calculating site energy distribution were also summarized. [Display omitted] • Over 45 kinetic models, 70 isotherms and 45 fixed bed models were reviewed and categorized. • Models' physical meanings, application conditions, and misconceptions were analyzed. • Two information criteria were recommended to evaluate the validity of the models. • Calculation methods for thermodynamics including site energy distribution were provided. • Associations and disparities between fixed-bed and solute transport models were discussed. [ABSTRACT FROM AUTHOR]

• Experiment in three homes using mixed-methods and physical measurements. • Indoor air temperature fluctuations like those of EMPC of space heating. • Night setback-users found the heating control unacceptable. • Acceptance was motivated by economic or environmental benefits. Recent simulation-based studies have indicated that Economic Model Predictive Control (EMPC) of space heating systems can exploit the thermal mass in residential buildings for demand response (DR) purposes in district heating systems. However, there is a lack of studies on residents' perception and acceptance of the fluctuating indoor air temperature behaviour inherent in EMPC of space heating. This paper reports on a case study featuring the residents of three one-story houses located in Denmark. The houses were equipped with technology enabling remote actuation of radiator thermostats and collection of various indoor environmental data. Four different temperature boost interventions mimicking the typical behaviour of EMPC of radiators were executed while a mixed-methods triangulation design, employing questionnaires and semi-structured interviews, was used to collect subjective data. Data showed that residents accepted the behaviour but only after the benefits of the EMPC were explained. The acceptance was motivated by either the prospect of saving money, environmental benefits, or a combination of both. The results thereby indicate that explaining the benefits of EMPC is important if residents are to abandon their current preferences and practices in favour of an EMPC concept. The explanation should consider the diversity in current preferences, expectations, and level of technological pre-knowledge. In addition, the paper also reports on a range of findings related to technical aspects of realising EMPC in practice. [ABSTRACT FROM AUTHOR]

In buildings, occupant behaviour is recognised as a major contributing factor to energy demand and in particular to heating consumption. To achieve thermal comfort within the heating season, people report to use heat in very different ways; for example behaviours include switching on the heating system, putting on warm clothes, drawing curtains, changing rooms, making a hot drink and using a hot water bottle. While research has focused on subjective accounts using interviews, diaries and questionnaires, little is known about the frequency and probability of these behaviours. Using a mixed-method approach, this paper reports on the results of a field study in dwellings using wearable and environmental sensors. The analysis investigates the probability of these behavioural responses as a function of seven independent variables; (1) external and (2) internal monitored temperature, (3) probability of heating being on or off, (4) time of the week, (5) time of the day, (6) the three categories of the predictive thermal comfort model, and (7) the three categories of the adaptive thermal comfort model. Results show that participants were more likely to increase their clothing and activity level as internal temperature decreased, although there was no significant change in activity level throughout the course of a day. Methodologically, this paper demonstrates the effectiveness of different statistical tools in analysing occupants’ behaviours. Substantively, this paper emphasises the need for future research to gather objective data on what people do. [ABSTRACT FROM AUTHOR]

Improving energy-saving performance and the indoor thermal environment of village room has become a social hot issues. This paper presented a kind of new encapsulation way of packaging 48 # paraffin phase change material in the structure of Kang and Firewall to improve its thermal performance, this method fundamentally improves energy-saving performance and the indoor thermal environment of rural residential housing. Using temperature and heat flux of inspection equipment, this paper tested the change rule of temperature both phase change storage and ordinary Kang and Firewall. By using automatic temperature recording devices, air temperature of the two rooms are also tested. According contrast and analysis of the test result, it is found that the temperature fluctuation of Kang, Firewall with phase change energy storage is smaller than the other one without phase change energy storage; the temperature fluctuation of the phase change room is the other one without phase change energy storage. So the indoor thermal environment is improved. The research proved the advantage of adapting 48 # paraffin phase change material in Kang and Firewall and provides a new idea for the development of phase change storage Kang and Firewall. [ABSTRACT FROM AUTHOR]

This paper investigates the dynamic cooling performance of a novel system combining natural ventilation with diffuse ceiling inlet and thermally activated building systems (TABS). This system is tested in the lab under three climatic conditions representing typical seasons in Denmark, including a typical winter day, a typical day in the transitional season and a typical summer day. The corresponding dynamic control strategies have been designed for these three cases in the measurements. In the winter case, TABS have to be activated for two hours to supply extra heating to ensure a comfortable indoor environment. In the case representing the transitional season, changing the ventilation rate during both occupied and un-occupied hours can ensure the thermal autonomy of the room without extra heating or cooling from TABS. In the summer case, the free cooling potential of ventilation air is limited due to the relatively high inlet air temperature. Therefore, TABS are activated for ten hours to supply the extra cooling. Due to the use of the diffuse ceiling, the whole-body and local thermal comfort conditions are quite good in the measurements. The dynamic measurements in the paper are beneficial to the future design and application of this system. [ABSTRACT FROM AUTHOR]

The goal of this paper is to identify the effects of in-pore transport of liquid water and water vapor as well as phase changes on the hygrothermal behavior of earthen buildings. Indeed, one of the main assets used to promote these constructions is their role in moisture buffering hence temperature and relative-humidity quality controlling. However, there is no clear consensus yet concerning the impact of these phenomena on the global energy performance of the buildings. A coupled model is therefore proposed in this paper, based on heat and mass balances inside the earthen walls, in order to clarify this question. This model considers separately the kinematics of each phase (e.g. liquid water, vapor, dry air and solid matrix), in interaction with each other. It also takes into account the impact of pore water confinement on the liquid-to-vapor phase change, in particular on the resulting latent heat released or absorbed. The model is successfully compared to experimental results on instrumented full-scale rammed earth wall subjected to temperature cycles. It eventually allows identifying the singular hygrothermal behavior of earth material by testing the range of applicability of the simplifying assumptions which are commonly made in function of the permeability of the tested material. [ABSTRACT FROM AUTHOR]

To address the problems and limitations identified through a comprehensive evaluation in Part I paper, several modifications are made in model inputs, treatments, and configurations and sensitivity simulations with improved model inputs and treatments are performed in this Part II paper. The use of reinitialization of meteorological variables reduces the biases and increases the spatial correlations in simulated temperature at 2-m (T2), specific humidity at 2-m (Q2), wind speed at 10-m (WS10), and precipitation (Precip). The use of a revised surface drag parameterization further reduces the biases in simulated WS10. The adjustment of only the magnitudes of anthropogenic emissions in the surface layer does not help improve overall model performance, whereas the adjustment of both the magnitudes and vertical distributions of anthropogenic emissions shows moderate to large improvement in simulated surface concentrations and column mass abundances of species in terms of domain mean performance statistics, hourly and monthly mean concentrations, and vertical profiles of concentrations at individual sites. The revised and more advanced dust emission schemes can help improve PM predictions. Using revised upper boundary conditions for O 3 significantly improves the column O 3 abundances. Using a simple SOA formation module further improves the predictions of organic carbon and PM 2.5 . The sensitivity simulation that combines all above model improvements greatly improves the overall model performance. For example, the sensitivity simulation gives the normalized mean biases (NMBs) of −6.1% to 23.8% for T2, 2.7–13.8% for Q2, 22.5–47.6% for WS10, and −9.1% to 15.6% for Precip, comparing to −9.8% to 75.6% for T2, 0.4–23.4% for Q2, 66.5–101.0% for WS10, and 11.4%–92.7% for Precip from the original simulation without those improvements. It also gives the NMBs for surface predictions of −68.2% to −3.7% for SO 2 , −73.8% to −20.6% for NO 2 , −8.8%–128.7% for O 3 , −61.4% to −26.5% for PM 2.5 , and −64.0% to 7.2% for PM 10 , comparing to −84.2% to −44.5% for SO 2 , −88.1% to −44.0% for NO 2 , −11.0%–160.3% for O 3 , −63.9% to −25.2% for PM 2.5 , and −68.9%–33.3% for PM 10 from the original simulation. The improved WRF/Chem is applied to estimate the impact of anthropogenic aerosols on regional climate and air quality in East Asia. Anthropogenic aerosols can increase cloud condensation nuclei, aerosol optical depth, cloud droplet number concentrations, and cloud optical depth. They can decrease surface net radiation, temperature at 2-m, wind speed at 10-m, planetary boundary layer height, and precipitation through various direct and indirect effects. These changes in turn lead to changes in chemical predictions in a variety of ways. [ABSTRACT FROM AUTHOR]

Improving the performance of air-to-air heat recovery systems, as measured by supply air temperature efficiency, is an important energy saving strategy that is often regulated by building codes. The high nonlinearity of supply air temperature efficiency with airflow rate in a run-around heat recovery system makes the trend prediction of supply air temperature efficiency especially challenging for field measurement. This paper proposes a simple and novel field measurement based methodology, supported by the power law relationship of air-side heat transfer, to evaluate the performance of run-around heat recovery systems. A system dependent power, signature power , is proposed that establishes a linear relationship between the supply air temperature increment across the supply air heat exchanger and a parameter—the maximum temperature difference between exhaust and supply airstreams divided by the signature power of the supply airflow rate. This methodology can predict the supply air temperature efficiency and is verified using four run-around heat recovery systems with field measurements. This new methodology can possibly be applied to other types of air-to-air heat recovery systems. This paper also describes a tuning method for determining the signature power based on field measurements and addresses the heat recovery efficiency of run-around heat recovery systems. [ABSTRACT FROM AUTHOR]

In two earlier papers we proposed a process assumption - based design method, one aim of which is the determination of the thermal requirement of a building by investigating the building functioning as a dynamic thermal system. The principal constraint of that determination is the building indoor temperature range to be no more than 2 °C. In this paper we focus on the thermal requirement of maximum WWR (window-to-wall ratio) allowed by the constraint as a function of envelope U -value and ambient temperature amplitude. Seven US cities are studied to represent a range of ambient temperature amplitudes. As the window part of a building’s envelope is a prominent architectural feature of the building, WWR and its allowed maximum in terms of thermal autonomy are the signature/reflection of local ambient temperature amplitude and the variety of envelopes of building stock in each locality. Such signal characteristics are otherwise referred to as regional architecture. [ABSTRACT FROM AUTHOR]

This paper is focused on increasing the knowledge on methods for calibrating BES models and to get more insights of different approaches for the optimization of the calibration process. The paper will be centred in the evaluation of a multistage guided search approach. It defines an iterative optimization procedure which starts with the assignment of probabilistic density functions to the unknown parameters, followed by a random sampling and running batch of simulations. It then finishes with an iterative uncertainty and sensitivity analysis combined with a re-assignment of the ranges of variation of the strong parameters. The procedure converges when no new influencing parameters are found. This method is applied to a real case study consisting of an unoccupied office building located in Lleida (Spain). The measured indoor temperature has been used to determine the uncertainty and precision of the method. The effect of the size of the sampling, the number of iterations and the parameters of the global sensitivity method are analyzed in detail. The results of this paper exemplify the degree of accuracy of multistage guided search approaches, and illustrate the reasons how these analyses can contribute to the improvement of more refined calibration methods. [ABSTRACT FROM AUTHOR]

Given the need to rein in the rise in the global average temperature, decarbonizing the electricity sector, which accounts for nearly 50% of global greenhouse gas (GHG) emissions, is crucial. The suitability of nuclear power as a base-load technology and its relatively negligible GHG emissions raised expectations of a nuclear renaissance, until the Fukushima disaster brought discussions about nuclear power’s potential to a standstill. However, completely ruling out nuclear may not be sustainable owing to the realities of rising energy demand, climate change considerations, and the need for reliable base-load supply technology, especially in the case of fast growing economies in the Association of South East Asian Nations (ASEAN). The Fukushima disaster was a wake-up call for both governments and the nuclear industry. Led by the International Atomic Energy Agency, the more advanced economies conducted stringent reviews of safety standards and emergency response procedures in the event of a catastrophe. Meanwhile the industry responded with strong commitments towards “Fukushima proof” designs, alongside other advancements towards “safer” fission power. In the ASEAN context, we argue in this paper that in addition to the economic advantage, nuclear power can help address the twin objectives of energy security and mitigating climate change effects. In ASEAN, there is still a strong momentum towards nuclear power development due to strategic considerations. In this paper, we reviewed in a holistic approach the various factors influencing decision making on nuclear power. Using ASEAN as a case study, we argue that nuclear power remains an important option and should be taken up rapidly if decarbonizing electricity generation is a grave concern. We also provide some recommendations towards the “safer nuclear” for ASEAN at the end of this paper. [ABSTRACT FROM AUTHOR]

In this paper a dynamic model suitable for simulating real operating conditions of air-based photovoltaic thermal (PVT) systems is presented. The performance of the model is validated by using the operational data collected from the building integrated photovoltaic (PVT) systems installed in two unique buildings. The modelled air outlet temperature and electrical power match very well with the experimental data. In Solar Decathlon house PVT, the average (RMS) error in air outlet temperatures was 4.2%. The average (RMS) error in electrical power was also 4.2%. In the Sustainable Buildings Research Centre PVT, the average errors (RMS) of PV and air temperatures were 3.8% and 2.2%, respectively. The performance of the PVT system under changing working condition is also analysed in this paper. The analysis includes the effect of ambient air temperature, air inlet temperature, air flow rate and solar irradiation on thermal, electrical, first law and second law efficiencies. Both the thermal and the 1st law efficiencies almost linearly increased with the increase of the ambient temperature. However, the PVT electrical efficiency and the second law efficiency decreased with the increase of the ambient temperature. All efficiencies expect the second law efficiency decreased with increase of the PVT air inlet temperature. The second law efficiency first increased and then reduced. With increasing the air flow rate all the efficiencies increased. The electrical and second law efficiencies become less sensitive when the air flow rate exceeded 300 l/s. Both the thermal and the 1st law efficiencies decreased while the electrical efficiency and the second law efficiency increased with the increase of the solar irradiation. The efficiencies found to be very sensitive for low level of solar irradiations. At about 400 W m −2 irradiation efficiencies became less sensitive. [ABSTRACT FROM AUTHOR]

Rainfall is one of the climate components which is very important for an agrarian country with a tropical climate like Indonesia. There are so many variables that can affect the intensity of rainfall, including humidity, air temperature, speed and wind direction. However, not all of these variables can have a significant effect, therefore, we need a modeling technique that can select and shrink the predictor variables so as to make the model simpler. One of the techniques used is the Lasso (least absolute shrinkage and selection operator). The purpose of this study is to model rainfall intensity using lasso regression and determine which variable have the greatest influence on rainfall intensity. This paper also designs an application system that can be used to implement Lasso regression. The response variables in the form of daily rainfall at the Citeko observation station, Bogor Indonesia is assumed to have normal distribution. Rainfall intensity modeling involves 16 predictor variables, namely the maximum temperature, minimum temperature, average temperature, average humidity, sun exposure, maximum wind speed, wind direction when maximum wind speed and 8 other categorical variables are the most frequent wind direction. The resulting Lasso regression model successfully select and shrink the variables used to 9 variables only. In addition, based on the AIC and coefficient of determination indices for the model evaluation, the Lasso regression shows satisfying results rather than classical multiple linear regression. In Lasso regression, AIC value is 5901.20 where in classical model it is 5911.43. Also, Lasso regression coefficient of determination value is greater that is 22.73% while in classical model is 21.41%. From lasso regression model that has been obtained, it is known that the most frequent wind direction to the north is the variable that has the greatest influence on rainfall intensity. The Lasso regression application has been successfully created so that it can facilitate the user in uploading data, exploration of data and variables, Lasso regression analysis and report result. [ABSTRACT FROM AUTHOR]

In this paper, Ag doped MnO 2 -CNT nanocomposite was fabricated by using simple co-precipitation route. The synthesized nanocomposite was employed as adsorbent for elimination of Acridine Orange dye. The structural analysis of as synthesized Ag doped MnO 2 -CNT nanocomposite confirms the presence of (111) plane of Ag, (104) of carbon and (110) plane of MnO 2. Processing of operational variable parameters such as, pH, adsorbent dose, and initial dye concentration with respect to contact time on adsorption of Acridine Orange was optimized and evaluated using Response Surface Methodology. The fit of the predictive model for the removal of dye was in good agreement with the experimental value. Isotherm data was modelled by means of Langmuir, Freundlich, Temkin and Dubinin- Radushkevich isotherm. Langmuir isotherm offered the best fit to experimental data proposing homogeneous dispersion of adsorption sites. Furthermore, the suitability of the adsorbent was also investigated by fitting the adsorption data with pseudo-second-order kinetic model. The recuperation and reusability of the adsorbent and adsorbate has made this process inexpensive and appropriate for large scale applications. Image 1 • Synthesis of Ag-doped MnO 2 (AgMC) nanocomposites by co-precipitation method. • AgMC exhibits remarkable adsorption properties optimized by RSM approach. • Investigation of adsorption in real water sample using AgMc. [ABSTRACT FROM AUTHOR]

Causes of the brittle fracture of the locomotive draw hook are investigated in this paper. The failure occurred when the heavy freight train accelerated after stop at signal between the two stations in winter time (the air temperature of −2 °C). The performed analysis showed that the brittle fracture was caused by the superimposition of several factors. As the main factor heavily coarsened microstructure, exhibiting insufficient toughness can be considered. Based on the analysis, it was found that the relevant standard, prescribing mechanical properties of the locomotive draw hooks, should be critically revised, to ensure safety operation in various conditions. • In the study, the brittle fracture of the locomotive draw hook is investigated. • Examined draw hook exhibit insufficient mechanical properties, especially the low impact toughness at low temperatures. • The FEM analysis showed an important contribution of the additional bending loading on the final failure. • To prevent similar failures in the future, the significant changes in the relevant standards about the draw hooks properties are required. [ABSTRACT FROM AUTHOR]

High-Altitude Ice Crystals (HAIC) constitute a hazard to commercial aircraft flying near deep convective weather due to jet-engine power loss and air data probes malfunction. HAIC can stick to warm metal surfaces in jet-engines and cause engine surge, stall, flameout and rollback, power loss, as well as engine compressor damage due to ice shedding. Along with these events, disruption to aircraft systems are noted when HAIC are ingested into air data probes (Pitot tube and/or Total Air Temperature -TAT- sensor), causing erroneous measurements of temperature and air speed. Particularly, the TAT probe incorrectly reporting zero degrees Celsius or in error is known to be evidence of ice crystals in the atmosphere surrounding the aircraft. These TAT anomalies are due to the accumulation of ice crystals in the TAT sensor, producing a zero degrees Celsius reading, generating failures in airspeed indicators and acting as potential incident/accident precursors. In this paper, TAT events from pilot reports and Flight Data Monitoring (FDM) are analyzed. TAT FDM data analysis covers two types of engines, which are used on short, medium and long-range routes. The study includes eight aircraft fleet types. Based on these analyses, we present a sensor-failure-tolerant heuristic that generates a reliability indicator, founded on the differences between the TAT and the engine's inlet temperature sensors. It aims to provide early warnings to pilots regarding HAIC events and prevent potential data errors and system failures. • High-Altitude Ice Crystals (HAIC) can obstruct aircraft pitot probes during the cruise phase. • Total Air Temperature (TAT) probe anomalies are evidence of ice crystals in the atmosphere. • TAT events from pilot reports and Flight Data Monitoring are analyzed. • We present different heuristics that generates reliability indicators regarding TAT events. • Routes flying through the Inter-Tropical Convergence Zone are more likely to experience TAT events. [ABSTRACT FROM AUTHOR]

• Eight methods to obtain near-surface temperature to monitor CLUHI. • Two kinds of human thermal indices for CLUHI research. • Urban-rural contrast and regression analysis methods to calculate CLUHI intensities. • Spatiotemporal variation and six types of associated factors of CLUHI. • Five potential research directions. The urban thermal environment is closely related to the well-being of many city dwellers. Rich achievements have been obtained for canopy layer urban heat island (CLUHI) studies. Nevertheless, the monitoring and associated factors of CLUHI have not been systematically and timely reviewed. Therefore, this paper aimed to solve this issue to some extent by reviewing the fruitful research progress of CLUHI from the above-mentioned two aspects. The main findings were as follows. (1) Eight methods were adopted to obtain near-surface temperature data for CLUHI research, including four observation, two numerical modeling, remote sensing and data assimilation methods. (2) Air temperature was usually used rather than apparent temperature indices. Obvious differences existed between them, especially under humid hot or cold windy conditions. (3) The CLUHI intensity was generally defined as the differences in temperature between urban and suburban or rural stations or regions by population, land cover/land use, etc, or derived using regression analysis between temperature and impervious surface percentage. (4) The diurnal, monthly, seasonal or interannual variation of CLUHI has been generally analyzed in various global regions. (5) Six types of factors were analyzed, including meteorological conditions, air pollution, socioeconomic factors, urban underlying surface condition, inland or coastal type and landform conditions, and combined effects of some factors. (6) Five potential research directions were proposed, including improvement of data acquisition, sharing and use, considering apparent thermal indices, focus on the rarely studied regions, cities and scales, improving the calculation of CLUHI intensity, and attention to more associated factors and driving force analysis methods. This review can provide references for future CLUHI research and the construction of climate-resilient, livable, low-carbon cities. [ABSTRACT FROM AUTHOR]

Traditional air conditioning may be inappropriate for electric vehicles due to its moving parts noise besides using chlorofluorocarbons that harm the environment. In addition, it consumes a significant portion of the stored energy in batteries, reducing the vehicle's driving range. So, in this paper, a novel design of thermo-electric cooling (TEC) system coupled with a photovoltaic (PV) panel replacing the vehicle roof is studied. This system consists of a sandwich of PV panel outside the vehicle and TEC inside with a heat sink system integrated between them. The air temperature variation in the cabin during the daytime is predicted by solving a complete mathematical transient thermal model of the whole system before and after mounting the cooling system. The air streams through the vehicle moving are exploited to improve the TEC and PV system performance. The system performance is investigated for different cases during the day with and without including the PV output power and for the vehicle parks inside or outside. The results indicate that, for each scenario, the number of used TEC modules influences the system performance where the best number varies between 128 and 98. Coupling the PV panel with the TEC system reduces the daily required energy from batteries by about 19%. Running the TEC system during parking from 8 to 10 am decreases the cabin air temperature from 47.5 to 34°C while the input power declines by about 45%, which reduces the interior temperature to 25°C in 10 min (transition time). The contribution of the PV panel based on the studied conditions can increase the range of the vehicle by 10.4 km/day and about 160kWh/year energy saving. The reduction in the input power during transition time reaches 27.8% when the vehicle speed increases from 30 to 60 km/h, while this ratio declines to 10.8% as the vehicle speed rises from 60 to 90 km/h. During vehicle moving, powering the TEC system by the PV panel only can prevent the cabin temperature from rising over 40°C, whereas during parking, there is an optimum fan air velocity that gives the maximum reduction of the cabin temperature. • A novel design of a thermo-electric air conditioning system for electric vehicles is studied. • Contribution of the PV panel reaches 19% of the daily energy consumption in some scenarios. • PV panel increases the range of the vehicle by 10.4 km and can save 160kWh/year. • The best number of TEC modules is about 128 for scenarios 1 and 2 and 98 for the others • Power the TEC by PV power in parking reduces the vehicle temperature less than ambient. [ABSTRACT FROM AUTHOR]

The intraseasonal reversal of the temperature over East Asia and the sudden stratospheric warming (SSW) are two abrupt events during the winter of 2020/21. The characteristics of these two events and their relationship are the focused issues in this paper. In winter 2020/21, there was a transition from cold to warm over East Asia. The surface air temperature (SAT) in East Asia suddenly changed from cold to warm with long duration. The cold period lasted from 21 November 2020 to 11 January 2021, while the warm period lasted from 19 January to 28 February 2021. And the transition of the cold to the warm was from 12 to 18 January 2021.There were significant differences of the atmospheric circulations between the cold and warm periods in the upper and lower troposphere. During the cold period, both of Ural Mountain High(UH) and Siberian High(SH) were stronger than normal, the Westerly Jet (WJ) was weakened and located to the area farther southerly than usual, the northerly wind anomalies and the cold advection occurred in East Asian; vice versa during the warm period. The mutations of the atmospheric circulations in the upper and lower levels were obvious during the transition period, especially for UH and SH. A strong SSW event occurred in the stratosphere at the beginning of 2021. As a result, the stratospheric polar vortex was largely weakened and deviated to the areas over Ural Mountains and nearby, the polar westerly wind turned to easterly wind and the temperature gradient reversed. The abnormal changes of the temperature and the geopotential height over the Ural Mountains area in the stratosphere were closely related to the SSW. These abnormal signals caused by the SSW gradually transmitted from stratosphere to troposphere over the Ural Mountains and the polar region, leading to the weakening and collapse of tropospheric UH and further caused the transition from cold to warm in East Asia. The SSW may be the most critical factor leading to the turning from cold to warm over East Asia during the winter of 2020/21. • Focuses on two newest and unexpected events during the winter 2020/21. • The intraseasonal reversal of the temperature over East Asia and the sudden stratospheric warming (SSW). • The characteristics of these two events and their relationship are examined.Apart from SSW. • Other factors of affecting the intraseasonal turning are also pointed out and discussed in this paper. [ABSTRACT FROM AUTHOR]

Changes in winter low flow (WLF) in cold-region rivers affect engineering design, water quality, and river ecosystem health. This paper aims to quantify to what extent WLF will change under climate warming and to propose a practical forecasting model for WLF predictions. The new concept of cumulative watershed temperature (CWT) is used as a convenient lumped surrogate for complicated hydrological processes that influence WLF. Statistical analyses of century-long flow data from the Fraser River in British Columbia, Canada show a strong dependence of WLF on CWT. In winter season, time series of CWT and WLF are shown to each divide into a falling and a rising limb at the data point of their lowest values, being −358 °C and 827 m3/s (historical averages), respectively. The falling and rising limbs describe the cumulative freezing and thawing effects of air temperatures fluctuating around the freezing point on WLF changes. The correlation between CWT and WLF (time series) data points on the rising limbs forms the forecasting model, expressing WLF as a function of CWT in terms of their z-scores. The model takes input of Global Circulation Model (GCM) projections of temperature increases by the end of 21st century under different Representative Concentration Pathways (RCPs), and predicts changes of Fraser River WLF from the historical average. RCP4.5 causes a 22.6% increase (ensemble average from six GCMs). RCP8.5 increases WLF by 20% (for some future years) to 44% (for others). The methods reported in this paper can be adapted to other cold regions. • Climate warming causes future winter low flow of the Fraser River in B.C. to increase. • Cumulative watershed air temperature controls the magnitude of winter low flow. • Design low flows from traditional methods need corrections due to climate warming. [ABSTRACT FROM AUTHOR]