Numerical study the influence of balcony in college dormitory on indoor environment in winter: A case study in Jinan, China

The ventilation rate of dormitory in winter affects the living quality and learning state of students, while the balcony will affect the indoor ventilation of dormitory. In order to explore the influence of different locations, floor heights and building types on the ventilation rate and indoor environment of the dormitory in winter, this paper used the computational fluid dynamics software PHOENCIS and the multi-area network model software CONTAM coupling calculation method to simulate the indoor ventilation conditions of the dormitory in a university with or without balconies under three building types. The results show that the average ventilation volume with balcony is 44.04 m3/h lower than that without balcony. When there are balconies, the room ventilation rate of the first floor of ordinary rectangular building, the second floor of L-type building and the first floor of rectangular-ambulatoryplane building are the largest. The room ventilation rate of different positions on the same floor of ordinary rectangular building is the lowest. Considering comprehensively, it is better to choose rectangular-ambulatory-plane dormitory buildings when there is a balcony.publishedVersio

A study of modelling and monitoring time-between-events with control charts

Ph.DDOCTOR OF PHILOSOPH

Numerical Evaluation of the Local Weather Data Impacts on Cooling Energy Use of Buildings in an Urban Area

AbstractAccurate weather data plays an important role in the evaluation of building energy consumption in urban areas. The local air temperature and local wind speed can vary significantly due to the influence of microclimate conditions, while those parameters have a significant effect on energy demand especially in the summer. This study provides a new coupled numerical approach that building energy simulation (BES), using the airport weather data, transfers building surface temperature data to computational fluid dynamics (CFD) as the boundary conditions. In addition, the outdoor thermal environment is simulated using the CFD method and local weather data is calibrated and transferred to BES as the real-time meteorological data. A daily coupled simulation is performed for a building located in a specified urban density accounting for actual wind speed and direction. The comparison shows that the difference for daily building energy consumption is up to 2.5% using the airport weather data and local weather data. Therefore, accurate estimation of local weather data is necessary when on-site measured data is not available

Prediction of Electricity Consumption of a HVAC System in a Multi-Complex Building Using Back Propagation and Radial Basis Function Neural Networks

This study examined approaches to predict electricity consumption of a Heating, Ventilation and Air- Conditioning (HVAC) system in a multi-complex building using two neural network models: Back Propagation (BP) and Radial Basis Function (RBF) with input nodes, e.g., temperature, humidity ratio, and wind speed. Predicting HVAC energy consumption of buildings is a crucial part of energy management systems. We used two main neural network models, BP and RBF, to evaluate the prediction performance of electricity consumption of HVAC systems. The BP neural network method exhibited good performance, but it exhibited relatively large fluctuations and slow convergence in the training process. In contrast, RBF exhibited relatively fast learning and reduced computing costs. The HVAC energy consumption rate of working days was higher than that of non-working days. The results indicate that the prediction of HVAC energy consumption using neural networks can effectively control the relationship between the HVAC system and environment conditions.publishedVersio

Origin and tuning of the magnetocaloric effect for the magnetic refrigerant MnFe(P1-xGex)

Neutron diffraction and magnetization measurements of the magneto refrigerant Mn1+yFe1-yP1-xGex reveal that the ferromagnetic and paramagnetic phases correspond to two very distinct crystal structures, with the magnetic entropy change as a function of magnetic field or temperature being directly controlled by the phase fraction of this first-order transition. By tuning the physical properties of this system we have achieved a maximum magnetic entropy change exceeding 74 J/Kg K for both increasing and decreasing field, more than twice the value of the previous record.Comment: 6 Figures. One tabl

Single image super resolution based on multi-scale structure and non-local smoothing

In this paper, we propose a hybrid super-resolution method by combining global and local dictionary training in the sparse domain. In order to present and differentiate the feature mapping in different scales, a global dictionary set is trained in multiple structure scales, and a non-linear function is used to choose the appropriate dictionary to initially reconstruct the HR image. In addition, we introduce the Gaussian blur to the LR images to eliminate a widely used but inappropriate assumption that the low resolution (LR) images are generated by bicubic interpolation from high-resolution (HR) images. In order to deal with Gaussian blur, a local dictionary is generated and iteratively updated by K-means principal component analysis (K-PCA) and gradient decent (GD) to model the blur effect during the down-sampling. Compared with the state-of-the-art SR algorithms, the experimental results reveal that the proposed method can produce sharper boundaries and suppress undesired artifacts with the present of Gaussian blur. It implies that our method could be more effect in real applications and that the HR-LR mapping relation is more complicated than bicubic interpolation

Use-wear experimental studies for differentiating flint tools processing bamboo from wood

Bamboo is widespread in south China and is one of the major organic resources in daily use through history due to its similar potential use value as wood. Due to the unfavourable preservation conditions and taphonomic alteration, the rare discovery of well-preserved organic remains from Palaeolithic sites means there is a lack of direct studies on the technology and behaviour of early prehistoric humans. Use-wear analysis has been proved as a reliable method to detect evidence left by working wood and bamboo on stone artefacts. This study aims to provide an experimental reference of use-wear features and patterns to identify and interpret the exploration of bamboo and wood resources in prehistory. In this experiment, 12 flint flakes were selected for processing bamboo stems and pine branches with working motions of whittling, sawing, and chopping. The results show that the use-wear features, including edge scarring, edge rounding, and polish, of bamboo-working and wood-working are distinctive. Edge scarring is closely related to the working motion, and moderate bright to very bright polish is a significant feature associated with bamboo-working. It is possible to distinguish wear traces caused by bamboo-working from those by wood-processing through a combination of low-power and high-power techniques under a 3D digital microscope

A Macroscopic Perspective on Lithic Technology and Human Behavior during Pleistocene in Zhejiang Province, Southeastern China

Paleolithic archeological remains were not reported from Zhejiang until 2002. Up to now, over 70 Paleolithic sites and/or localities have been recovered through a series of surveys mainly in the north part of Zhejiang. An overview of the Paleolithic record and archeological sequence in this region during the Early to Late Pleistocene are present from a macroscopic perspective in this article, as well as the brief introduction of lithic technology and human adaptation in south China. In general, the lithic assemblages in Zhejiang represent the features of Pebble Industry in south China and show a trend of reduction on the size of stone artifacts since the Late Paleolithic. It is presumed that prehistoric humankind has shown the behavioral strategies as followed: a) exploited local raw material; b) the utilization of core and the degree of proficiency in knapping have been improved gradually; c) the retouching focused on the areas of edges; and d) preferred to use sharp edges of tools