The designed UCNPs were firstly applied in enhancing TSTF UCL. The amplified UCL was attributed to reduction of surface quenching and improvement of 1550 nm absorption. The design provided a novel strategy for studying the mechanism of TSTF UCL.
This paper presented a novel solar collector that can work in air or water heating mode depending on the seasonal requirement. The dual-function solar collector (DFSC) integrated with a building as well as a reference building without the DFSC were built to test thermal behavior in passive air heating mode during winter. The buildings were equipped with an apparatus to control the room temperature. During the testing procedure, experimental study on the DFSC system was carried out under two conditions, where the indoor temperature was controlled and non-controlled. The results showed that the average temperature of the test room was about 3.43 °C higher than that of the reference room under the non-controlled condition. When the room temperature was controlled at 18 °C, the power consumptions of the test room and reference room were 4.322 kWh and 7.796 kWh, respectively. Consequently, the corresponding daily power consumption saved could reach up to around 3.5 kWh. Moreover, a dynamic numerical model on the DFSC along with the building was developed taking the fin effect of the Cu-tubes into account. The numerical results are found to be well consistent with the measured data. A parametric study on with/without Cu-tubes and depth of the air channel was carried out. It is found that the existing Cu-tubes functioning as water heating can enhance the air heating efficiency when the depth of air channel is of a suitable size.
4 April 2024 in Environmental Monitoring and Assessment
A new method for improving the retrieved aerosol fine-mode fraction (550) based on the current Moderate Resolution Imaging Spectroradiometer (MODIS) ocean algorithm is proposed. In the current MODIS ocean algorithm, the top of the atmosphere (TOA) apparent reflectance needs calculation from lookup tables (LUTs). The weighting parameters used in the calculation show an obvious spectral dependence, which is not taken into account in the current algorithm. The main measure taken in this study is to consider the spectral dependence of the weighting parameters. The MODIS aerosol products and the Aerosol Robotic Network (AERONET) data of Hong Kong Hok Tsui, Midway Island, Martha’s Vineyard Coastal Observatory (MVCO) and COVE, Virginia, where aerosols exhibit different loading and size distribution, are used to test the new method. The results show that the new method improves the retrieved fine-mode fraction, which is underestimated in anthropogenic-dominated aerosol conditions and overestimated in the sea salt-dominated aerosol conditions by the current algorithm. The correlation of the retrieved fine-mode fraction between the new method and AERONET is much higher (correlation coefficient, r = 0.92) than that between the current MODIS and AERONET (r = 0.80). The retrieved aerosol optical depth (AOD) is also improved. More AODs retrieved from the new method lie within the expected error bars.
1 December 2012 in Journal of the Atmospheric Sciences
Coastal and island Aerosol Robotic Network (AERONET) sites are used to determine characteristic aerosol modes over marine environments. They are compared with the assumed modes used in the operational Moderate Resolution Imaging Spectroradiometer (MODIS) ocean aerosol algorithm, and the results show that 1) the standard deviation values of three fine aerosol modes (0.6) and one dustlike aerosol mode (0.8) are much higher than the corresponding statistical AERONET modal values (0.45 and 0.6, respectively). The values of three sea salt aerosol modes (0.6) are somewhat lower than the corresponding statistical AERONET modal value (0.675). 2) The number median radius of the current fine and dustlike aerosol modes cannot span the dynamic range of corresponding aerosol distribution properly. 3) AERONET products show that the standard deviation and the number median radius exhibit an obvious negative correlation, especially for sea salt and dustlike aerosol modes. According to this, a refinement of the current aerosol modes is made. These revised modes are used in a version of the MODIS retrieval over ocean. Compared with the current aerosol modes: 1) more retrieved aerosol optical depths (AODs) from the revised aerosol modes lie within the expected error bars and 2) the linear regression lines of the retrievals from the revised aerosol modes and AERONET are closer to the 1:1 line.
20 June 2009 in International Journal of Remote Sensing
A non‐linear iterative physical algorithm that simultaneously retrieves atmospheric temperature, water vapour distribution and surface skin temperature from Moderate Resolution Imaging Spectroradiometer (MODIS) longwave infrared radiances is presented. The retrieval algorithm uses clear‐sky radiances measured by MODIS in Taiwan Strait for both day and night, and shows that it is capable of retrieving medium‐scale atmospheric temperature and water vapour. Sea surface temperature is retrieved with an accuracy similar to that achieved by MOD07 products. Evaluation of retrieval total precipitable water vapour (TPW) is performed by comparisons with retrievals from MOD07 products and data from a ground‐based sunphotometer. These show that MODIS retrieval of TPW, in general, agrees with other sounder retrievals of TPW. The total totals index (TTI) distribution retrieved from MODIS data is similar to that from MOD07 products.