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We consider the initial and progressive enlargements of a filtration generated by a marked point process (called the reference filtration) with a strictly positive random time. We assume Jacod's equivalence hypothesis, that is, the existence of a strictly positive conditional density for the random time with respect to the reference filtration. Then, starting with the predictable integral representation of a martingale in the initially enlarged reference filtration, we derive explicit expressions for the coefficients which appear in the predictable integral representations for the optional projections of the martingale on the progressively enlarged filtration and on the reference filtration. We also provide similar results for the optional projection of a martingale in the progressively enlarged filtration on the reference filtration. This paper represents the continuation of research contained in our previous paper in EJP [11].

When trading American and Asian options in the FX derivatives market, banks must calculate prices using a complex mathematical model. It is often observed that different models produce varying prices for the same exotic option, which violates the non-arbitrage requirement of derivative risk management. To address this issue, we have studied a fully parameterized local volatility model for pricing American/Asian options. This model, when implemented using a grid or Monte-Carlo numerical method, can be efficiently and accurately calibrated to FX market skew volatilities. As a result, the model can provide reliable prices for exotic options during daily trading activities.

We consider the initial and progressive enlargements of a filtration generated by a marked point process (called the reference filtration) with a strictly positive random time. We assume Jacod's equivalence hypothesis, that is, the existence of a strictly positive conditional density for the random time with respect to the reference filtration. Then, starting with the predictable integral representation of a martingale in the initially enlarged reference filtration, we derive explicit expressions for the coefficients which appear in the predictable integral representations for the optional projections of the martingale on the progressively enlarged filtration and on the reference filtration. We also provide similar results for the optional projection of a martingale in the progressively enlarged filtration on the reference filtration.

Climate change is a hot issue in the global scale. The some varieties of phenological phase of plants (trees, grasslands and crops et al.) can directly and objectively reflected climate change and Commonly, the response of plant phenology to climate change is sensitive, especially to climatic factors such as precipitation, temperature, soil characteristics in the growing environment, and sometimes can be considered as an indicator of climate change. Those meteorology and soil factors must be taken into account when we build phenological model so as to quantitatively study the relationship between climate change and plant phenology. Beside of those factors, the high frequency and multi-scale acquisition of phenological observation data is also the basis for phenological model researches. Since February of 2020, China Meteorological Administration (CMA) has established 25 vegetation ecological observation sites in Inner Mongolia autonomous region, Shaanxi, Hebei, Sichuan, Guangxi, Fujian and Anhui provinces. The automatic vegetation eco-meteorological observation instruments, whichi are composed of image sensor (digital camera), multispectral sensor, laser altimeter, point cloud laser radar and sound sensor, have been installed in the sites. They can provide so much products as image of plant community, normal difference vegetation index (NDVI), plant height, canopy height and animal sound at present. Of all these products, image data of plant community can be further retrieved to generate the greenness chromatic coordinate (Gcc) data, which can be widely applied into the phenological studies and the validations of satellite terrestrial vegetation products. After months of experimental operation, these equipments show the great ability to monitor the growth and development of terrestrial plants in China. This ability also lays a foundation for the establishment of the plant ecological observation network in China (China Vegetation Ecological Meteorological Observation Network).KEYWORDS：Plant phenology, near-surface-based measurement, observation network

We consider the initial and progressive enlargements of a Brownian filtration with a random time, that is, a strictly positive random variable. We assume Jacod’s equivalence hypothesis, that is, the existence of a strictly positive conditional density for the random time with respect to the Brownian filtration. Then, starting with the predictable integral representation of a martingale in the initially enlarged Brownian filtration, we derive explicit expressions for the components which appear in the predictable integral representations for the optional projections of the martingale on the progressively enlarged filtration and on the Brownian filtration. We also provide similar results for the optional projection of a martingale in the progressively enlarged filtration on the Brownian filtration.

Soil moisture plays a crucial role in the study of agricultural drought monitoring, yield prediction, soil erosion, and so on, which is of great significance for agriculture, drought, and climate. With the advantages of high precision, high spatial and temporal resolution, and non-destructive, the automatic soil moisture observing instrument has become an important component of automatic soil moisture observation station for the meteorological department in china. In the process of observing soil moisture, the accuracy of data is seriously affected by the calibration methods, equipment stability, soil texture, etc. Therefore, it is especially important to establish a quality control method for the automatic soil moisture observation data from the origin of affecting the observation quality. To solve the outstanding quality problems in the automatic soil moisture observation data, firstly, based on the historical data, the inherent variation characteristics of soil moisture were studied. Secondly, combined with the instrument observation principle, data characteristics and error sources of abnormal data, classified and statistical analyzed the form of abnormal data caused by various reasons and given the threshold, this paper preliminarily puts forward a practical set of quality control methods for the hourly soil moisture observation data. Finally, the application effect of the quality control method was verified by using the data in china in 2019. The result shows that: (1) Four mainly categories of abnormal data are gross errors, mutation, abnormal high values, and stiffness, which are mostly caused by instrument failure, abnormal soil hydrological constant, and unreasonable calibration of sensors. (2) The method of frequency characteristic detection can identify the error caused by instrument fault. (3) This quality control method can effectively detect abnormal data in china. At present, the method has been applied to the Integrated Meteorology Observation Data Quality Control System.

The observations of soil moisture are invaluable for researching the trends in the water cycle related to climate or land-surface cover change. Nevertheless, the data quality of soil moisture observation stay in a low level and the acquaintance of equipment operation monitoring is lacking, which lead the soil moisture data unavailable. This paper introduces a soil moisture observation system briefly we have designed based on the Atmospheric Observing System Operation and Monitoring. Then the emphasis is mentioned on the quality control of observational data. The vertical distributions of soil moisture observation in September for example are presented after the data quality control, and the soil in the north is dry and in the south is wet while considering the Yangtze River as the boundary.

Condensable particulate matter is the predominant contributor to the total particulate matter emissions of coal-fired power plants. In the studied ultralow-emission coal-fired power plant, the emission concentrations of condensable and filterable particulate matter in the stack were 1.6 mg/Nm3 and 7.9 mg/Nm3. The organic fraction in condensable particulate matter was mainly composed of alkanes, esters, and other complex organic compounds. The organic fraction comprised 54% of the total concentrations of condensable particulate matter tested at the stack. The organic fraction in condensable particulate matter might contribute significantly to the organic carbon in atmospheric PM2.5. SO42– accounted for the highest concentrations in the inorganic fraction of condensable particulate matter. Na and Ca were predominant metal elements in the inorganic fraction. The inorganic fraction of condensable particulate matter mainly contributed to the water-soluble ions in atmospheric PM2.5. The total particulate matter...

The low-low temperature electrostatic precipitator (LLT-ESP) has been developed recently to improve the performance of traditional low temperature electrostatic precipitators. In this study, the particulate matter emission characteristics and removal efficiencies of were investigated on an LLT-ESP. Filterable particulate matter (FPM) was tested according to ISO standard 23210-2009, and condensable particulate matter (CPM) was tested according to U.S. EPA Method 202. The LLT-ESP showed excellent removal efficiency for FPM, with total FPM removal efficiencies of more than 99.9%. The removal efficiencies of FPM increased with the rising particulate diameter; for FPM2.5, removal efficiencies ranged from 96.5 to 98.2%. The LLT-ESP also showed remarkable removal efficiencies for CPM, with CPM removal efficiencies of more than 60.9%. The removal mechanism of CPM in the ESP was different from that of FPM. After the LLT-ESP, the quantity relationship between FPM and CPM reversed. For further reduced emission of PM...

In this paper, we consider two kinds of enlargements of a Brownian filtration F: the initial enlargement with a random time τ , denoted by F (τ) , and the progressive enlargement with τ , denoted by G. We assume Jacod's equivalence hypothesis, that is, the existence of a positive F-conditional density for τ. Then, starting with the predictable representation of an F (τ)-martingale Y (τ) in terms of a standard F (τ)-Brownian motion, we consider its projection on G, denoted by Y G , and on F, denoted by y. We show how to obtain the coefficients which appear in the predictable representation property for Y G (and y) in terms of Y (τ) and its predictable representation. In the last part, we give examples of conditional densities.

The low-low temperature electrostatic precipitator (LLT-ESP) is one of the most used devices for pollutant control in ultra-low emission coal-fired power plants. This study investigated the influence of the LLT-ESP on polycyclic aromatic hydrocarbons (PAHs) distributions in flue gas from an ultra-low emission coal-fired power plant. The total gas-phase PAH concentration was reduced from 27.52 μg/m3 to 3.38 μg/m3. The total particulate-phase PAH concentration decreased from 14.36 μg/m3 to 0.34 μg/m3. The removal efficiency of the LLT-ESP for gas-phase and particulate phase carcinogenic higher molecular weight (HMW) PAHs was 85% and 99%, respectively. The total concentration of 16 selected PAHs in feed coal was 98.16 μg/g. The fly ash particle size successively decreased from Electric Field 1 (F1) to Electric Field 4 (F4). The total PAH concentration decreased from F1 to F2 but increased again from F3 to F4. The flue gas cooling process significantly contributed to the elimination of both gas- and particulate-phase PAHs in the flue gas. Presumably, most of the condensed PAHs were adhered to or absorbed in the fly ash and were scavenged in Field 1. Both gas- and particulate-phase 5- and 6-ring PAHs in the flue gas were completely removed in Field 1. The discharge process in the electric fields may promote the formation of several 4- or 5-ring PAHs. In this study, benzo[k]fluoranthene (BKF) and benzo[a]pyrene (BaP) were regenerated in the particles rather than in the flue gas during the discharge process in the electric fields.

This paper presents a prototype ECDIS as developed by the Research Group on ECDIS (RGE) of Dalian Maritime University (DMU). It describes the configuration, the functions and the characteristics of the system. The results of sea and land trials are also presented.