Analysis and Comparison of the Thermal Retention Properties of Shading Devices in the Real-World and Dynamic Thermal Models within the UK Built Environment

The built environment accounts for 40% of the UK’s carbon footprint, with half of this involving building operations. Additionally, as approximately 50% of the building energy is linked to heating applications, managing thermal loss has become critical in reducing the energy load of buildings. One of the methods to reduce heat loss in buildings is utilising shaded devices. However, most research into the effectiveness of utilising window coverings to reduce heat loss has been carried out in experimental situations within a controlled laboratory, which does not reflect real-life conditions. To investigate the gap in knowledge in the UK around the use of shading devices, a survey study was conducted with the participation of UK building industry professionals. The results highlighted the lack of awareness of the impact shading devices can have on thermal retention. To assess the effects of shading devices on thermal retention, two real-world case studies were conducted using internal cellular blinds. These studies illustrated the importance of correct installation methods when using shading devices, as well as the effectiveness of sealed blinds in reducing heat loss through windows. A further survey was conducted to evaluate the effectiveness of BEMS software packages in modelling shading devices amongst UK building energy modellers which indicated that the software databases had insufficient information on shading devices. To further assess the capability of BEMS software packages illustrating the impact of shading devices, the results from the case study were compared with dynamic thermal model results generated by four software packages. The real-world study demonstrated a positive trend between the correct use of shading devices and the reduction of key energy performance indicators, such as heat loss and heating energy consumption. By comparing this to the results from the simulations, inefficiencies in the software were exposed specifically when assessing the total heating consumption

Self-esteem, general and sexual self-concepts in blind people

Background: People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. Materials and Methods: This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-concept using Eysenck self-esteem and Rogers’ self-concept questionnaires. The correlation between above two variables was measured using Statistical Package for the Social Sciences (SPSS) software by Pearson correlation test. Results: Mean [± standard deviation (SD)] age of patients was 30.9 ± 8 years. The mean (±SD) of general self-concept score was 11 ± 5.83. The mean (±SD) of self-esteem score was 16.62 ± 2.85. Pearson correlation results showed a significant positive correlation between self-esteem and general self-concept (r = 0.19, P = 0.025). The mean of sexual self-concept scores in five subscales (sexual anxiety, sexual self-efficacy, sexual self-esteem, sexual fear, and sexual depression) were correspondingly 11 ± 4.41, 19.53 ± 4.53, 12.96 ± 4.19, 13.48 ± 1.76, and 5.38 ± 2.36. Self-esteem and self-concept had significant positive correlation with sexual anxiety (r = 0.49; P < 0.001) (r =-.23; P < 0.001) and sexual fear (r = 0.25; P = 0.003) (r = 0.18; P = 0.02) and negative correlation with sexual self-efficacy (r =-0.26; P = 0.002) (r =-0.28; P = 0.001) and sexual-esteem (r =-0.34; P < 0.001) (r =-0.34; P < 0.001). Conclusion: Self-esteem and self-concept had significant correlation with sexual anxiety and sexual fear; and negative correlation with sexual self-efficacy and sexual-esteem. © 2015 Journal of Research in Medical Sciences

A Pareto Front Approach to Bi-objective of Distillation Column Operation Using Genetic Algorithm

In this paper, an exergy analysis approach is proposed for optimal design of distillation column by using Genetic algorithm. First, the simulation of a distillation column is performed by using the shortcut results and irreversibility in each tray is obtained. The area beneath the exergy loss profile is used as Irreversibility Index for exergy criteria. Then, two targets optimization algorithm (SA, Simulated Annealing) is used to maximize recovery and minimize irreversibility index in a column by six different variables (Feed Condition, Reflux Rate, Number of theoretical stage, Feed Trays (Feed Splitting, three variables)). SA uses one objective function for the purpose or alters two targets optimization to one target optimization. Then, GA optimization algorithm is used for two targets optimization except Pareto set which is used instead of objective function; finally, the results are compared with SA results. Then, one pump-around is considered to obtain better results (OPT2). Irreversibility index criterion is compared with exergetic efficiency, constant and variable feed composition splitters are considered.Key words: Exergy analysis; Irreversibility index; Genetic algorithm; Process optimization; Distillation colum

Simulation and Microstructure Prediction of Resistance Spot Welding of Stainless Steel to Carbon Steel

Joining of stainless steel to carbon steel is widely used in various industries. Resistance spot welding (RSW) is a suitable process for joining steel sheets. Due to the complexity and importance of optimizing the parameters, numerical simulation of this process was considered. In this research, the electrical-thermal-mechanical simulation of RSW of 304 stainless steel to St37 carbon steel was performed using finite element method (FEM). Then, the simulated weld nugget size was compared with the experimental results of optical microscopy (OM). In addition, diffusion of metallic elements of the steels in the molten region was simulated using Fick’s equation and compared with experimental results of energy-dispersive X-ray spectroscopy (EDS). It was shown that diffusion of Cr and Ni through the weld nugget, would make a new stainless steel structure. Microstructure prediction of the heat affected zone (HAZ) was performed using Koistinen–Marburger and Leblond–Devaux equations to predict the percentage of martensite and ferrite-perlite phases during the heating and cooling stages of the specimens from room temperature to the peak temperature and cooling down under the Mf temperature. The results of this simulation were validated by scanning electron microscopy (SEM) images and shear tensile and micro-hardness test results. The simulation results showed that increasing the heat input from 1250 A during 0.5 s to 3750 A during 1.5 s, increases the percentage of martensite, from 40% to 80%, in the HAZ and widens the martensite region

Pan-PPAR Agonist, Bezafibrate, Restores Angiogenesis in Hindlimb Ischemia in Normal and Diabetic Rats

Introduction. The aim of this study was to investigate the effect of bezafibrate as a pan-PPAR agonist on angiogenesis and serum nitrite, the main metabolite of nitric oxide (NO), vascular endothelial growth factor (VEGF) and VEGF receptor-2 (VEGFR-2) concentrations in hindlimb ischemia model of normal and type I diabetic rats. Methods. 28 male Wistar rats were divided into control and diabetic groups. Then, all rats underwent unilateral hindlimb ischemia. After recovery, they were randomly assigned to one of the following experimental groups: (1) control; (2) control + bezafibrate (400 mg/kg/day); (3) diabetic; (4) diabetic + beztafibrate. After three weeks, blood samples were taken and capillary density was evaluated in the gasterocnemius muscle of ischemic limb. Results. Bezafibrate increased capillary density and capillary/fiber ratio in ischemic leg of diabetic and control rats (P < 0.05). Serum VEGF and VEGFR-2 concentrations did not alter after bezafibrate administration, however, serum nitrite concentration was significantly higher in bezafibrate-treated groups than non-treated groups (P < 0.05). Discussion. It seems that bezafibrate, as a pan PPAR agonist, restores angiogenesis in hindlimb ischemic diabetic animals and is useful for prevention and/or treatment of peripheral artery disease in diabetic subjects

Improving the Segmentation of Anatomical Structures in Chest Radiographs using U-Net with an ImageNet Pre-trained Encoder

Accurate segmentation of anatomical structures in chest radiographs is essential for many computer-aided diagnosis tasks. In this paper we investigate the latest fully-convolutional architectures for the task of multi-class segmentation of the lungs field, heart and clavicles in a chest radiograph. In addition, we explore the influence of using different loss functions in the training process of a neural network for semantic segmentation. We evaluate all models on a common benchmark of 247 X-ray images from the JSRT database and ground-truth segmentation masks from the SCR dataset. Our best performing architecture, is a modified U-Net that benefits from pre-trained encoder weights. This model outperformed the current state-of-the-art methods tested on the same benchmark, with Jaccard overlap scores of 96.1% for lung fields, 90.6% for heart and 85.5% for clavicles.Comment: Presented at the First International Workshop on Thoracic Image Analysis (TIA), MICCAI 201

Assessing the performance gap of two dynamic thermal modelling software tools when comparing with real-time data in relation to thermal loss

Managing thermal loss is a key topic that needs further investigation as it has a direct link to reducing the energy load in buildings. One of these thermal loss management methods can be the use of shading devices. Dynamic thermal models normally used at the early stages of the building design can play an important role in the decision-making process regarding the use of shading devices. This paper presents the results of a real-world study assessing the potential of using a sealed cellular blind as a passive energy conservation method, where the real-world results are compared with the simulated results generated with environmental design solutions limited thermal analysis software (EDSL Tas) and integrated environmental solutions virtual environment (IES VE). During the real-world study, a positive impact of having blinds was seen whereby the window surface temperature increased and office heating energy consumption was lowered. Both software tools were able to predict a similar trend of results for the window surface temperature in with and without blind scenarios whereas for energy consumption although in the presence of a blind a consistent correlation is seen between measured and calculated values but not without a blind. This can be attributed to the inability of the software tools in demonstrating the effect of in filtration in the absence of a blind or shading device i.e., a clear window scenario.Practical Application: The performance gap analysis regarding thermal loss between dynamic thermal models and real-world settings within buildings can enhance the predictability of the building energy software tools used by designers. Early design inputs within buildings can prevent costly building re-work to improve the building’s energy performance. This can also improve the understanding within the building industry of the importance of reducing thermal loss through the use of shading devices and ensuring the software tools used to model these devices are as close to real-world settings as possible