Helmert Variance Component Estimation for Multi-GNSS Relative Positioning

The Multi-constellation Global Navigation Satellite System (Multi-GNSS) has become the standard implementation of high accuracy positioning and navigation applications. It is well known that the noise of code and phase measurements depend on GNSS constellation. Then, Helmert variance component estimation (HVCE) is usually used to adjust the contributions of di¿erent GNSS constellations by determining their individual variances of unit weight. However, HVCE requires a heavy computation load. In this study, the HVCE posterior weighting was employed to carry out a kinematic relative Multi-GNSS positioning experiment with six short-baselines from day of year (DoY) 171 to 200 in 2019. As a result, the HVCE posterior weighting strategy improved Multi-GNSS positioning accuracy by 20.5%, 15.7% and 13.2% ineast-north-up(ENU) components, compared to an elevation-dependent (ED) priori weighting strategy. We observed that the weight proportion of both code and phase observations for each GNSS constellation were consistent during the entire 30 days, which indicates that the weight proportions of both code and phase observations are stable over a long period of time. It was also found that the quality of a phase observation is almost equivalent in each baseline and GNSS constellation, whereas that of a code observation is different. In order to reduce the time consumption off the HVCE method without sacrificing positioning accuracy, the stable variances of unit weights of both phase and code observations obtained over 30 days were averaged and then frozen as a priori information in the positioning experiment. The result demonstrated similar ENU improvements of 20.0%, 14.1% and 11.1% with respect to the ED method but saving 88% of the computation time of the HCVE strategy. Our study concludes with the observations that the frozen variances of unit weight (FVUW) could be applied to the positioning experiment for the next 30 days, that is, from DoY 201 to 230 in 2019, improving the positioning ENU accuracy of the ED method by 18.1%, 13.2% and 10.6%, indicating the effectiveness of the FVUW.Peer ReviewedPostprint (published version

Investigation of Carbon Tax Pilot in YRD Urban Agglomerations—Analysis and Application of a Novel ESER System with Carbon Tax Constraints

AbstractThis paper attempts to explore the dynamic behavior of energy-saving and emission-reduction (ESER) system in Yangtze River Delta (YRD) urban agglomerations, which has not yet been reported in present literature. The novel YRD urban agglomerations carbon tax attractor is achieved. A scenario study is carried out. The results show that, the ESER system in YRD urban agglomerations is superior to the average case in China, in which the impacts on economic growth are almost the same. The economic property of YRD urban agglomerations is the main cause why the ESER system of YRD urban agglomerations being superior

目次 : 『千葉医学雑誌 オープン・アクセス・ペーパー』 92E巻4号 2016年8月

<p>(a) Clustering evolution of oil importers. (b) Evolution of cluster ratios.</p

Well-posedness of the Solution to D-P Equation with Dispersive Term

Abstract: In this paper,we study the D-P equation with dispersive term.By applying Kato&apos;s semigroup approach, one can obtain the local well-posedness of the equation in Sobolev space (H s , s &gt; 3 2 ). By using the prior estimates we can obtain the existence of global smooth solutions under the initial value u 0 ∈ H s (R) , s &gt; 3 2

Electromagnetic complementary media with arbitrary geometries and non-conformal boundaries

A generalized folded transformation procedure is presented for the space with arbitrary shapes. General expressions for the constitute parameters of complementary media are deduced, which can be readily applied to design complementary media based transformation optics devices (CMTOD) with arbitrary shapes. It's no longer limited to the situation when the inner and outer boundaries of the CMTOD are conformal or similar shapes, and can be available for the non-conformal situations. Three kinds of CMTOD are designed and studied, which involves a super-lens, an external cloak that hides object outside the cloaking shell, and an illusion optics device that transforms one object to another. Full-wave simulations are carried out to validate the proposed approach. The generalization introduced here makes a step forward for the flexible design of CMTOD with arbitrary geometries

Can Carbon Trading Promote Low-Carbon Transformation of High Energy Consumption Enterprises?—The Case of China

This paper explores the effect of carbon trading on low-carbon transformation of high energy consumption enterprises in China. Based on the mechanism of interaction and restriction among high energy consumption enterprises, carbon verification agencies and the government, a tripartite evolutionary game model is constructed. The three-dimensional dynamic system is built to analyze the behavior patterns of the three parties. The evolution path of the tripartite game is visualized, and the low-carbon transformation states of high energy consumption enterprises in different situations are described. The results show that the high energy consumption enterprises, verification organization and the government cannot reach the optimal game equilibrium (low-carbon transformation, verification and supervision) temporarily when seeking their own interests. The corresponding measures should be taken with different situations of the tripartite game. No matter what strategy the government chooses, the low-carbon transformation could be promoted by carbon trading through carbon verification mechanism

Exploring the effectiveness of fiscal decentralization in environmental expenditure based on the CO2 ecological footprint in urban China

Abstract Under the fiscal decentralization of government environmental management, this paper investigates the relationship between local environmental protection expenditure (LEPE) and CO2 ecological footprint (CEF). Unlike conventional emissions-based greenhouse gas metrics, this research calculates per capita CEF for 253 Chinese cities, considering both carbon emissions and absorption. The dynamic spatial Durbin model demonstrates that LEPE not only reduces a city’s own CEF but also exerts a long-term influence on neighboring cities, signifying competitive dynamics among local governments in LEPE. This decentraliztion of environmental budget authority may yield adverse outcomes. Further analysis reveals an inverted U-shaped relationship between CEF and LEPE intensity, partly mirroring the environmental Kuznets curve. Different developmental stages should consider economic levels when allocating resources to environmental budgets. The low-carbon pilot policy strengthens LEPE, with varying effects across Chinese urban agglomerations, remaining consistent post-environmental protection tax introduction. These findings hold critical reference value for local policymakers aiming to collaboratively adjust market-oriented environmental policies

Principle of the sliding-time windows method.

<p>The time series of oil imports are sliced with 23 superposed windows.</p

Evolution of information entropy and standard information entropy of global oil trade network.

<p>The overall trend is increasing gradually and slowly. It means the global oil trade network tends to be homogeneous slightly.</p