Study on Mitigation Method of Solder Corrosion for Crystalline Silicon Photovoltaic Modules

The corrosion of 62Sn36Pb2Ag solder connections poses serious difficulties for outdoor-exposed photovoltaic (PV) modules, as connection degradation contributes to the increase in series resistance (RS) of PV modules. In this study, we investigated a corrosion mitigation method based on the corrosion mechanism. The effect of added sacrificial metal on the reliability of PV modules was evaluated using the oxidation-reduction (redox) reaction under damp heat (DH) conditions. Experimental results after exposure to DH show that the main reason for the decrease in power was a drop in the module’s fill factor. This drop was attributed to the increase of RS. The drop in output power of the PV module without added sacrificial metal is greater than that of the sample with sacrificial metal. Electroluminescence and current-voltage mapping analysis also show that the PV module with sacrificial metal experienced less degradation than the sample without sacrificial metal

Gender Differences and Relationships among Lifestyle and Reproductive Health in University Students

PURPOSE: University students happen to be in a transitional period at the beginning of one's adult life and thereby establish the basis for their health care. The negative lifestyles followed by students during this period can also affect their reproductive health. The purpose of this study was to identify lifestyle, reproductive health, gender differences and relationships between lifestyle and reproductive health in university students. METHODS: We used a descriptive cross-sectional design. A total of 300 subjects were enrolled. Data were collected using structured questionnaires between October 11 and 25, 2017 and analyzed using SPSS 25.0. Subjects agreed to undergo a face-to-face interview, including administration of the Health Promotion Lifestyle Profile II (HPLP-II) and reproductive health (knowledge, attitude, and behaviors). RESULTS: The mean age of the subjects was 21.4 years. HPLP-II and reproductive health behaviors were significantly different between the genders. The scores of physical activity and nutrition in females were significantly lower than males. The scores of safe sex and sexual responsibility in females were significantly higher than males, and the score of genital health management was significantly lower in females than males. High HPLP-II score was observed to be in correlation with high reproductive health attitudes and behaviors. CONCLUSION: The result revealed differences in lifestyle and reproductive health between both the genders. For improvement of reproductive health of university students, provision of lifestyle intervention including healthy nutritional habits and physical activity is imperative

End-to-End Differentiable Learning to HDR Image Synthesis for Multi-exposure Images

Recently, high dynamic range (HDR) image reconstruction based on the multiple exposure stack from a given single exposure utilizes a deep learning framework to generate high-quality HDR images. These conventional networks focus on the exposure transfer task to reconstruct the multi-exposure stack. Therefore, they often fail to fuse the multi-exposure stack into a perceptually pleasant HDR image as the inversion artifacts occur. We tackle the problem in stack reconstruction-based methods by proposing a novel framework with a fully differentiable high dynamic range imaging (HDRI) process. By explicitly using the loss, which compares the network's output with the ground truth HDR image, our framework enables a neural network that generates the multiple exposure stack for HDRI to train stably. In other words, our differentiable HDR synthesis layer helps the deep neural network to train to create multi-exposure stacks while reflecting the precise correlations between multi-exposure images in the HDRI process. In addition, our network uses the image decomposition and the recursive process to facilitate the exposure transfer task and to adaptively respond to recursion frequency. The experimental results show that the proposed network outperforms the state-of-the-art quantitative and qualitative results in terms of both the exposure transfer tasks and the whole HDRI process

The Relationship between Land Use and Temperature Change in Dallas County, Texas

This study examines the relationship between land use and temperature change in Dallas County, TX. The purpose of this research is to analyze the relationship between temperature and land use and to identify the primary factors contributing to the formation of urban heat islands based on different categories of land use. Specifically, this research analyzes the elements that contribute to the urban heat island effect in Dallas County using temperature data provided by remote sensing imagery and parcel-based land use data using Geographic Information System (GIS) technique and a correlation analysis method, which was employed to analyze the relationship between temperature and land use. The results of this study showed that every land use category has different temperature averages and those patterns were observed similarly in both 2000 and 2005. Parking, airport, commercial, industrial, and residential areas have relatively high temperatures. In contrast, water, undeveloped area and parks showed relatively low temperatures. Another major finding was ratio of land use composition affected the temperature of census tracts. Correlation analyses of land use and temperature in 2000 and 2005 indicate that various types of land use categories have significant relationships with temperature. Among them commercial, industrial, residential, parking, and infrastructure, are positively associated with temperature, while undeveloped, parks, water, and dedicated areas are negatively associated with temperature. Areas with a high ratio of commercial use showed the highest and undeveloped areas showed the lowest relationship. Furthermore, through the analysis of the relationship between land use and temperature change for five years (2000-2005), this study finds that temperature change depends on the ratio of each land use category change. The results of this study can help local planning and policy decisions which are related to urban land use planning concerning temperature change such as zoning, environmental regulations and open space preservation