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The multipath effect is a critical factor that prevents the Global Navigation Satellite System (GNSS) from achieving millimeter-level positioning accuracy. A multipath hemispherical map (MHM) is a popular approach to achieving real-time multipath error mitigation. The premise of the constructed MHM model is that the residuals in the grid only contain multipath errors and noise without any outliers. However, when there are numerous obvious outliers in each grid, the traditional quality control method is unable to detect them effectively. Therefore, we propose a multipath hemispherical map with strict quality control (MHM-S) to mitigate multipath errors. This method first uses the maximum phase delay to eliminate obvious outliers. Then, the 3-sigma rule and F-test are applied to remove the remaining few outliers in the grid. After applying the proposed MHM-S method, the experimental results show that when the PRN20 satellite is affected by outliers, the standard deviation (STD) reduction rate of the MHM-S residuals is 12.03% compared with the residual STDs of the MHM model. In addition, we evaluate the capabilities of MHM-S with carrier phase observation (MHM-SC) and carrier phase and pseudo-range observation (MHM-SCP) models in multipath error mitigation. Especially in the east direction, the positioning accuracy of the MHM-SCP model is improved by 48% compared with the MHM-SC model.

The study aims to reveal the impact of three sequential strict-lockdowns of COVID-19 measures on the air pollutants including NO 2 , SO 2 , PM 10 , and PM 2.5 in Ulaanbaatar, Mongolia during November 2020–February 2021 based on air quality network and satellite data. Based on measurements of automatic air quality sites in Ulaanbaatar, we found a substantial decrease in NO 2 (up to 45%), PM 10 (72%), and PM 2.5 (59%) compared to the same periods in the previous five years. On the other hand, up to a threefold increase in SO 2 concentration was seen. Compared to 2015–2020, the number of days exceeding the national air quality standard level of NO 2 decreased by 55% during November 2020–February 2021. A similar trend was observed for PM 10 and PM 2.5 (30% and 14%, respectively). Conversely, days exceeding the national air quality standard level of SO 2 increased by 58%. The third strict-lockdown exhibited significant reductions in pollutant concentrations. The percentage exceeding the national standard level for NO 2 , PM 10 , and PM 2.5 constituted 23%, 50%, and 67% during the lockdown periods while it was 89%, 84%, and 91%, respectively, for the same periods in the previous five years. Even though Sentinel 5P-TROPOMI data do not fully reflect the above findings, they add valuable insights into the spatial pollution pattern during strict-lockdown and non-lockdown periods. The study demonstrates that measures taken during the strict-lockdown periods clearly influenced the values of daily patterns of NO 2 , PM 10 , and PM 2.5 concentrations. On the contrary, it is important to note that SO 2 concentration increased during the last two winter months after 2019.

The scarcity of environmental data means that other sources of information are needed to complement empirical evidence for conservation decisions. We, therefore, aimed to explore Local Ecological Knowledge (LEK) on mammal abundance and qualitative population trends through interviews from 331 local people in and around Kogyae Strict Nature Reserve, Ghana. The results show that 62% of the respondents perceived that mammal abundances had decreased, 31% perceived stability, and 8% perceived that mammals had increased between 2006 and 2017. The respondents attributed the decline to habitat degradation and illegal hunting. The knowledge of local people about mammal population trends is consistent with reported mammal encounters by law enforcement rangers. However, the length of residence, location of communities, and cardinal direction of communities influenced local peoples’ knowledge of mammal abundance and population trends. Our results highlight the ability of LEK to provide reliable ecological information on animal abundance and qualitative population trends. Integrating LEK into monitoring and management is appealing because it can be cost-effective, enhance community participation, and provide novel insights into sustainable resource use.

The National Environmental Policy Act (NEPA), the foundational statute of environmental law, is under intense scrutiny with calls from critics on both sides of the political spectrum for repeal or reform. Although calls for NEPA reform are not new, they have intensified recently as the United States attempts to build renewable energy infrastructure to combat climate change. The recent passage of the Inflation Reduction Act highlighted this scrutiny. In order to secure enough votes to pass the bill, Senate Majority Leader Chuck Schumer (D-N. Y.) agreed to submit a series of NEPA and federal permitting reforms authored by Senator Joe Manchin (D-W.Va.) to Congress for a vote. The clamor for reform is based on a popular misconception that NEPA review causes delay in large infrastructure projects. This Article uses several recent analytical studies to show that this popular perception is incorrect and obscures the real reasons for federal project delays. The Article shows that environmental impact statements (EIS) are not that common and that NEPA analyses do not take an inordinate amount of time. It also reveals that NEPA reviews are not litigated often nor does NEPA litigation result in significant delays. It argues that NEPA analyses provide essential benefits that would be reduced or lost if NEPA were reformed. Finally, the paper recommends actions that agencies, the Council on Environmental Quality (CEQ), and Congress can implement, using tools, techniques, and resources currently at their disposal to decrease the burden of NEPA review without requiring an overhaul of the statute.

Due to the global lack of action to address emissions that cause climate change, more extreme options such as geoengineering, direct air capture, and carbon capture and sequestration (CCS) are being touted as both necessary and a way to enable the world to continue utilizing fossil fuels into the future. While all of these extreme options are economically prohibitive, technologically, CCS is the furthest developed, with pilot projects and some commercialization activities occurring. In addition to cost, the uncertain legal liability for CCS in the United States has so far hindered wide-scale adoption and development. This Article argues that due to the nature of the potential harms of CCS projects—asphyxiation, releases to the atmosphere that contribute to climate change, and degradation of water quality—the United States should adopt a strict liability regime. Inadvertent releases of carbon dioxide stored in CCS projects would impact the whole world by increasing the amount of carbon dioxide in the atmosphere. However, the local impacts could be much more pronounced. As demonstrated by spontaneous releases of supersaturated carbon dioxide in Africa and the gassing of a small Mississippi town due to a rupture of the carbon dioxide pipeline that runs through it, a large release of carbon dioxide can sicken or kill. Given the technology currently envisioned, there is also a potential for water contamination, which could be especially problematic in the arid West. The push by some would-be CCS project developers is to dramatically limit liability. However, harms might not be discovered or occur until decades after the initial injection. But those harms are currently foreseeable, and catastrophic. After discussing the current experience with CCS, this Article discusses the technology, its limitations, harms and their foreseeability, and how the risks caution for the affirmative adoption of strict liability. While this Article focuses on the CCS, it could just as easily be written about hydrogen, coal gasification, or small module nuclear reactors. Using legal paradigms, we can stop chasing squirrels in the energy transition.

The approach to further development in engineering geologic mapping of mineral reserves with respect to quality levels based on geoinformation models of deposits is substantiated. The algorithm and methods for delineation of clusters in the area of a seam using a vector index composed of simple indicators characterizing useful and harmful properties of coal are explicated. The results of new software trial are presented in the form of distribution of coal reserves for coking and power generation by quality levels and visualization of delineated clusters by means of plotting quality maps.

This paper presents a generalized targeting model that subsumes most known targeting problems. In this paper, a recurrent state is defined as a condition that requires reprocessing or rework. The generalized model can accommodate one or two specifications limits and can be used for the following quality characteristics: The nominal-the-better, the larger-the-better, and the smaller-the-better. This model can be used to find the optimal mean of a quality characteristic, as well as the optimal specification limits. In addition, the paper studies the conditions under which the solution to the proposed model can provide a global solution. The paper shows that, for some of the special cases and under very general conditions, the optimal lower limit should be zero and the optimal upper limit should be infinity. This paper proves that the expected profits improve for the case where only a lower limit on the quality characteristic is used, if a recurrent state is included by adding an optimized upper limit. A special case of the model is used to study the problem of determining a common mean for multiple products, as well as the optimal upper specification limits for each product. A solution procedure for maximizing the expected profits and obtaining the optimal solution is introduced. A numerical example is presented.

The making of water management decisions is based on estimates of water quality characteristics. Variations of those characteristics over space and time make it necessary to use statistical characteristics, including the reliability, reflecting the confidence in the correctness of conclusions made by water control authorities, and economic efficiency, reflecting the acceptability of the method chosen to obtain the data. Algorithms are proposed for determining the chosen characteristics. It is shown that, in addition to the well-known reliability characteristics, such as the error of the first kind and the error of the second kind, which are required for testing statistical hypotheses, the constructive dialogue between the participants of water relationships gains from taking into account the error of statistical decision, which is also referred to as differential threshold. Practical examples illustrate the possibility of establishing economically acceptable level of the above data quality characteristics by processing laboratory study data.

This article examines a firm's incentives to recall its product after learning that the product may harm consumers. It discusses whether courts should protect consumers who do not comply with recalls. Under the \"no duty to return\" rule, the firm bears the same liability no matter whether it has made a recall or not. The firm then may not recall the product as often as socially desired or provide insufficient reimbursement for consumers' return costs. In contrast, the \"full duty to return\" rule denies the firm's future liabilities after it makes a recall. More consumers then return the product, which may reduce the firm's incentives to recall the product. We show that the \"full duty to return\" rule may or may not generate more product recalls or higher social welfare. We also discuss the \"partial duty to return\" rule, which partially reduces the firm's liability after it makes a recall.

We review the work on max-stable laws and their max domains of attraction introduced by Pancheva (Lect Notes Math 1155:284–309, 1984 ). We introduce the concept of general max domain of strict attraction of the general max-stable laws, a subclass of the general max domain of attraction and prove new results. Some interesting examples also are discussed.