Parallel experimental study of a novel super-thin thermal absorber based photovoltaic/thermal (PV/T) system against conventional photovoltaic (PV) system

Photovoltaic (PV) semiconductor degrades in performance due to temperature rise. A super thin-conductive thermal absorber is therefore developed to regulate the PV working temperature by retrofitting the existing PV panel into the photovoltaic/thermal (PV/T) panel. This article presented the parallel comparative investigation of the two different systems through both laboratory and field experiments. The laboratory evaluation consisted of one PV panel and one PV/T panel respectively while the overall field system involved 15 stand-alone PV panels and 15 retrofitted PV/T panels. The laboratory testing results demonstrated the PV/T panel could achieve the electrical efficiency of about 16.8% (relatively 5% improvement comparing with the stand-alone PV panel), and yield an extra amount of heat with thermal efficiency of nearly 65%. The field testing results indicated that the hybrid PV/T panel could enhance the electrical return of PV panels by nearly 3.5%, and increase the overall energy output by nearly 324.3%. Further opportunities and challenges were then discussed from aspects of different PV/T stakeholders to accelerate the development. It is expected that such technology could become a significant solution to yield more electricity, offset heating load freely and reduce carbon footprint in contemporary energy environment

Case study of smart meter and in-home display for residential behavior change in Shanghai, China

Smart meters and in-home displays (IHD) have been recently adopted to help give residential consumers more control over energy consumption, and to help meet environmental and security of supply objectives. The paper aims to identify the effectiveness of smart meters and real-time IHDs in reducing Shanghai household energy consumption through a pilot investigation. The research results demonstrate the improved awareness, understanding, and attitudes towards the energy saving by smart meters and IHDs

Enterprise Knowledge Creation Entropy Theoretical Analysis and Knowledge Entropy Model Study

Entering the 21st century, the knowledge economy as a new economic realizes the alternative of intellectual resources of material resources in the economic operational process, and it can greatly save energy and improve economic efficiency. Thus the value of existence of the enterprises in the context of knowledge economy is that the enterprises can conduct knowledge creation, transfer and use more efficient compared with the market. In essence, enterprises are the entity of knowledge production, the peculiarity of it owned to the difference between knowledge production ability and using ability. This paper used the similarity fundamental of the cross and comprehensive of natural science and social science, and imported the basic principles of entropy theory in thermodynamics to study the mechanism of knowledge creation, the key pathways and mechanisms, pointed out that the knowledge entropy can greatly save energy and improve economic efficiency. At the same time constructed a mathematical model of knowledge creation, and pointed out that any enterprises must continue to carry out knowledge creation and knowledge transfer to increase negative entropy to promote sustained and have a healthy development. Key words: Entropy theory; Knowledge creation; Mode

Improving Viewpoint Robustness for Visual Recognition via Adversarial Training

Viewpoint invariance remains challenging for visual recognition in the 3D world, as altering the viewing directions can significantly impact predictions for the same object. While substantial efforts have been dedicated to making neural networks invariant to 2D image translations and rotations, viewpoint invariance is rarely investigated. Motivated by the success of adversarial training in enhancing model robustness, we propose Viewpoint-Invariant Adversarial Training (VIAT) to improve the viewpoint robustness of image classifiers. Regarding viewpoint transformation as an attack, we formulate VIAT as a minimax optimization problem, where the inner maximization characterizes diverse adversarial viewpoints by learning a Gaussian mixture distribution based on the proposed attack method GMVFool. The outer minimization obtains a viewpoint-invariant classifier by minimizing the expected loss over the worst-case viewpoint distributions that can share the same one for different objects within the same category. Based on GMVFool, we contribute a large-scale dataset called ImageNet-V+ to benchmark viewpoint robustness. Experimental results show that VIAT significantly improves the viewpoint robustness of various image classifiers based on the diversity of adversarial viewpoints generated by GMVFool. Furthermore, we propose ViewRS, a certified viewpoint robustness method that provides a certified radius and accuracy to demonstrate the effectiveness of VIAT from the theoretical perspective.Comment: 14 pages, 12 figures. arXiv admin note: substantial text overlap with arXiv:2307.1023

Towards Viewpoint-Invariant Visual Recognition via Adversarial Training

Visual recognition models are not invariant to viewpoint changes in the 3D world, as different viewing directions can dramatically affect the predictions given the same object. Although many efforts have been devoted to making neural networks invariant to 2D image translations and rotations, viewpoint invariance is rarely investigated. As most models process images in the perspective view, it is challenging to impose invariance to 3D viewpoint changes based only on 2D inputs. Motivated by the success of adversarial training in promoting model robustness, we propose Viewpoint-Invariant Adversarial Training (VIAT) to improve viewpoint robustness of common image classifiers. By regarding viewpoint transformation as an attack, VIAT is formulated as a minimax optimization problem, where the inner maximization characterizes diverse adversarial viewpoints by learning a Gaussian mixture distribution based on a new attack GMVFool, while the outer minimization trains a viewpoint-invariant classifier by minimizing the expected loss over the worst-case adversarial viewpoint distributions. To further improve the generalization performance, a distribution sharing strategy is introduced leveraging the transferability of adversarial viewpoints across objects. Experiments validate the effectiveness of VIAT in improving the viewpoint robustness of various image classifiers based on the diversity of adversarial viewpoints generated by GMVFool.Comment: Accepted by ICCV 202

Design, fabrication and experimental study of a novel loop-heat-pipe based solar thermal facade water heating system

This paper investigated a novel loop-heat-pipe based solar thermal facade heat-pump system for hot water from concept design, prototype fabrication and experimental test. Given the specific testing conditions, the solar thermal efficiency of the facade module achieved nearly 0.71 in average and the mean system's COP was about 5.0. It is expected that such novel LHP based solar thermal facade technology would further contributed to the development of the renewable (solar) driven heating/hot water service and therefore lead to significant environmental benefits

Reduced expression of Metastasis Suppressor-1 (MTSS1) accelerates progression of human bladder uroepithelium cell carcinoma

Background: Metastasis suppressor 1 (MTSS1) is a multi-functional cytoskeletal protein. Recent research showed that MTSS1 is a potential tumor suppressor in many types of cancer cells, including kidney and bladder cancer cells. However, the clinical implication of MTSS1 in human bladder uroepithelium cell carcinoma (BUCC) and its potential in suppressing BUCC tumorigenesis remains undetermined. In the present study, the expression of MTSS1 in human BUCC tissue samples, and correlations between MTSS1 and pathological grade and stage of the tumors were examined in BUCC specimens. The function of MTSS1 in BUCC progression was explored. Materials and Methods: The mRNA and protein expression of MTSS1 were examined in 68 BUCC tissue samples with matching adjacent normal bladder tissues using quantitative real-time PCR and western blotting. Furthermore, the bladder cancer cell line 5637 was used to determine the anticancer effect of MTSS1. Results: Lower MTSS1 mRNA expression was recorded in BUCC tissues compared to normal bladder tissues. A lower MTSS1 mRNA level was observed in tumors with high clinical stage and with high pathological nuclear grade. Likewise, MTSS1 protein expression in normal bladder tissue was significantly higher than that in BUCC tissue. The protein level of MTSS1 significantly negatively correlated with clinical stage and pathological nuclear grade of BUCC. Cumulative survival curves indicated that MTSS1 expression was negatively correlated with survival time: patients with a high level of MTSS1 had significantly longer survival time than those with a low level of MTSS1 (p<0.001). Overexpression of MTSS1 reduced BUCC cell proliferation, cell-cycle progression and colony formation, but had no influence on BUCC cell apoptosis. Conclusion: Overexpression of MTSS1 suppresses BUCC development, providing a novel perspective for BUCC tumorigenesis and a potential therapeutic target for BUCC

Numerical study on the thermal performance of earth-tube system in ningbo china

Earth tube system (ETS), which capitalizes on the high soil thermal inertia, is gaining popularity in recent years as an alternative to conserve energy for space cooling/heating in buildings. This paper presents a numerical study of the thermal performance of the basic ETS in Ningbo, China, through Computational Fluid Dynamic (CFD) modeling and then assesses its corresponding energy saving potential in the local climate. The primary impact parameters, i.e. pipe diameter and inlet air velocity, are discussed in terms of their influences on the ETS thermal performance. It is found that (1) the outlet temperature increased as the inlet velocity was higher as a result of reduced contact time between soil and airflow; (2) the outlet temperature increased when the diameter of the pipe was larger due to more airflow was passed through in a unit time; (3) a balance between outlet temperature required and volumetric airflow rate stipulated by regulations needed to be established provincially; (4) the ETS was estimated being able to provide cooling of 1185kWh in summer period (i.e. 86% of the projected energy demand) in Ningbo and attained a COP of 3.3. The overall research indicated the ETS has the potential to become the effective energy saving technology in Ningbo buildings and thus could contribute to the related carbon emission reduction in China.Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016