Effect of the Use Pattern on Performance of Heat Pump Water Heater

This paper presents the performance of the Heat Pump Water Heater (HPWH) in warm-up and recovery at different draw rates and draw amount. Performance is evaluated based on COPsys and Recovery Efficiency as measure. Results show that the recovery efficiency is proportional to draw amount. With increase of draw rate, stratification worsens causing lower recovery efficiency. This paper also presents numerical investigations to validate the influence of draw rate and analyze the influence of baffle, nozzle and inlet position on tank stratification by Three-Dimensional Computational Fluid Dynamics (CFD) methods. CFD results are confirmed with the experimental data indicating that higher draw rate destroys the tank stratification. Thermal performance of HPWH systems is strongly influenced by the thermal stratification in the water tank. The simulation results also show that the baffle, nozzle and inlet position helps preserving the stratification in the water tank. A dimensionless coefficient, the MIX number, ranging from 0 to 1, with 0 representing a perfectly stratified tank and 1 representing a fully mixed tank, has been used to characterize the tank stratification level

The Application of Evolutionary Algorithms to the Classification of Emotion from Facial Expressions

Emotions are an integral part of human daily life as they can influence behaviour. A reliable emotion detection system may help people in varied things, such as social contact, health care and gaming experience. Emotions can often be identified by facial expressions, but this can be difficult to achieve reliably as people are different and a person can mask or supress an expression. Instead of analysis on static image, the computing of the motion of an expression’s occurrence plays more important role for these reasons. The work described in this thesis considers an automated and objective approach to recognition of facial expressions using extracted optical flow, which may be a reliable alternative to human interpretation. The Farneback’s fast estimation has been used for the dense optical flow extraction. Evolutionary algorithms, inspired by Darwinian evolution, have been shown to perform well on complex,nonlinear datasets and are considered for the basis of this automated approach. Specifically, Cartesian Genetic Programming (CGP) is implemented, which can find computer programme that approaches user-defined tasks by the evolution of solutions, and modified to work as a classifier for the analysis of extracted flow data. Its performance compared with Support Vector Machine (SVM), which has been widely used in expression recognition problem, on a range of pre-recorded facial expressions obtained from two separate databases (MMI and FG-NET). CGP was shown flexible to optimise in the experiments: the imbalanced data classification problem is sharply reduced by applying an Area under Curve (AUC) based fitness function. Results presented suggest that CGP is capable to achieve better performance than SVM. An automatic expression recognition system has also been implemented based on the method described in the thesis. The future work is to propose investigation of an ensemble classifier implementing both CGP and SVM

Improvements on performance of a heat pump water heater system

Heat Pump Water Heater (HPWH) is classified as one renewable energy efficient technology, which could be explained by their environmentally friendly nature with low energy consumption. The Coefficient of Performance (COP) of the HPWH can be influenced by multiple factors: ambient temperature, relative humidity, hot water usage profile, the size and shape of heat exchangers (evaporator and condenser), type and shape of compressor, refrigerant, filling capacity of refrigerant, etc. Therefore, in this study, the performance of HPWH is critically examine to ascertain its optimal operation condition. Three main factors are considered here: use pattern of water in tank, drop-in refrigerant R1234yf and condenser configuration. This study examines two different models, HPWH-66 and HPWH-50. Simulation is employed and suggestions are made towards a better performance. The performance of HPWH system is found to strongly depend on the stratification of water in the storage tank, then 3D CFD simulation has been used to explore the entrance effects on the thermal tank. In the drop-in experiments, it is shown that R1234yf can be a desirable alternative for the baseline R134a without any special changes to the heat pump facility. By closing the valves at the inlet and outlet of one condenser circuit, a one-circuit condenser system could be achieved. For both refrigerant system, one-circuit condenser only brings the COP down within 5.5%. Finally, a linked EES-Fluent model has been developed to simulate the transient heating-up performance of the HPWH system with the validation by experimental data

Model-based evaluation and process development of continuous chromatography

Multi-column periodic counter-current (PCC) chromatography has been proposed as continuous capturing technology to improve the process productivity and resin capacity utilization, as well as reduce buffer consumption and equipment footprint, which is applying for monoclonal antibody (mAb) capture with Protein A affinity resin. Due to the complexity of continues chromatography, some mathematical framework should be developed to aid the process development. Please click Additional Files below to see the full abstract

BMP Signaling Mediated by BMPR1A in Osteoclasts Negatively Regulates Osteoblast Mineralization Through Suppression of Cx43

Osteoblasts and osteoclasts are well orchestrated through different mechanisms of communication during bone remodeling. Previously, we found that osteoclast‐specific disruption of one of the BMP receptors, Bmpr1a, results in increased osteoblastic bone formation in mice. We hypothesized that BMPR1A signaling in osteoclasts regulates production of either membrane bound proteins or secreted molecules that regulated osteoblast differentiation. In our current study, we co‐cultured wild‐type osteoblasts with either control osteoclasts or osteoclasts lacking BMPR1A signaling activity. We found that loss of Bmpr1a in osteoclasts promoted osteoblast mineralization in vitro. Further, we found that the expression of Cx43/Gja1 in the mutant osteoclasts was increased, which encoded for one of the gap junction proteins connexin 43/gap junction alpha 1. Knockdown of Gja1 in the mutant osteoclasts for Bmpr1a reduced osteoblastic mineralization when co‐cultured. Our findings suggest that GJA1 may be one of the downstream targets of BMPR1A signaling in osteoclasts that mediates osteoclast–osteoblast communication during bone remodeling. J. Cell. Biochem. 118: 605–614, 2017. © 2016 Wiley Periodicals, Inc.Disruption of Bmpr1a in osteoclasts promoted osteoblast mineralization when co‐cultured. Up‐regulation of gap junction Cx43/Gja1 in mutant osteoclasts is responsible for the enhanced osteoblast function.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135668/1/jcb25746_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135668/2/jcb25746.pd

The progress and prospect of sentinel lymph node mapping in endometrial carcinoma

Sentinel lymph node (SLN) refers to the initial site of the lymphatic drainage from a primary tumor area. Identifying the SLN and analyzing tumor involvement can predict the status of the remaining lymph nodes. Accordingly, sentinel lymph node mapping (SLN mapping) has been brought up and widely applied to cancer therapy for its illuminating role in clinical lymph node resection. Sufficient information to guide surgical pathological staging and adjuvant treatment in endometrial cancer can be rendered by SLN mapping, hence minimizing surgery injury and reducing the incidence of complications. Evidence suggests that using SLN mapping does not affect progression-free survival (PFS) and overall survival (OS) of endometrial cancer patients. Furthermore, there is increasing evidence that using SLN mapping has a high detection rate (DR), sensitivity, and negative predictive value (NPV) for patients with early-stage lower-risk endometrial cancer. This review aims to systematically summarize the advances and application prospects of SLN mapping in endometrial cancer, with an expectation of furnishing reference for the clinical application