A Parameter Self-Calibration Method for GNSS/INS Deeply Coupled Navigation Systems in Highly Dynamic Environments

The GNSS/INS (Global Navigation Satellite System/Inertial Navigation System) navigation system has been widely discussed in recent years. Because of the unique INS-aided loop structure, the deeply coupled system performs very well in highly dynamic environments. In practice, vehicle maneuvering has a big influence on the performance of IMUs (Inertial Measurement Unit), and determining whether the selected IMUs and receiver parameters satisfy the loop dynamic requirement is still a critical problem for deeply coupled systems. Aiming at this, a new parameter self-calibration method based on the norm principle is proposed which explains the relationship between IMU precision and the velocity error of the system; the method will also provide a detailed solution to calculate the loop steady-state tracking error, so it will eventually make a judgment about the stability of the tracking loop under present system parameter settings. Lastly, a full digital simulation platform is set up, and the results of simulations show good agreement with the proposed method

Product and Metal Stocks Accumulation of China's Megacities: Patterns, Drivers, and Implications

The rapid urbanization in China since the 1970s has led to an exponential growth of metal stocks (MS) in use in cities. A retrospect on the quantity, quality, and patterns of these MS is a prerequisite for projecting future metal demand, identifying urban mining potentials of metals, and informing sustainable urbanization strategies. Here, we deployed a bottom up stock accounting method to estimate stocks of iron, copper, and aluminum embodied in 51 categories of products and infrastructure across 10 Chinese megacities from 1980 to 2016. We found that the MS in Chinese megacities had reached a level of 2.6-6.3 t/cap (on average 3.7 t/cap for iron, 58 kg/cap for copper, and 151 kg/cap for aluminum) in 2016, which still remained behind the level of western cities or potential saturation level on the country level (e.g., approximately 13 t/cap for iron). Economic development was identified as the most powerful driver for MS growth based on an IPAT decomposition analysis, indicating further increase in MS as China's urbanization and economic growth continues in the next decades. The latecomer cities should therefore explore a wide range of strategies, from urban planning to economy structure to regulations, for a transition toward more "metal-efficient" urbanization pathways

Tafolecimab in Chinese patients with non-familial hypercholesterolemia (CREDIT-1): a 48-week randomized, double-blind, placebo-controlled phase 3 trialResearch in context

Summary: Background: Tafolecimab, a fully human proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibody developed for the treatment of hypercholesterolemia, demonstrated robust lipid-lowering efficacy and favorable safety in previous short-term studies. We aimed to assess the long-term efficacy and safety of tafolecimab in Chinese non-familial hypercholesterolemia (non-FH) patients. Methods: Non-FH patients at high or very-high cardiovascular risk with screening low-density lipoprotein cholesterol (LDL-C) level ≥1.8 mmol/L or non-FH patients with screening LDL-C level ≥3.4 mmol/L and on stable lipid-lowering therapy for at least 4 weeks, were randomized in a 2:2:1:1 ratio to receive subcutaneous tafolecimab 450 mg Q4W, tafolecimab 600 mg Q6W, placebo 450 mg Q4W, or placebo 600 mg Q6W, respectively, in the 48-week double-blind treatment period. The primary endpoint was the percent change from baseline to week 48 in LDL-C levels. Findings: A total of 618 patients were randomized and 614 patients received at least one dose of tafolecimab (n = 411) or placebo (n = 203). At week 48, tafolecimab induced significant reductions in LDL-C levels (treatment differences versus placebo [on-treatment estimand]: −65.0% [97.5% CI: −70.2%, −59.9%] for 450 mg Q4W; −57.3% [97.5% CI: −64.0%, −50.7%] for 600 mg Q6W; both P < 0.0001). Significantly more patients treated with tafolecimab achieved ≥50% LDL-C reductions, LDL-C < 1.8 mmol/L, and LDL-C < 1.4 mmol/L than placebo group at both dose regimens (all P < 0.0001). Furthermore, tafolecimab significantly reduced non-HDL-C, apolipoprotein B, and lipoprotein(a) levels. The most commonly-reported treatment emergent adverse events in the tafolecimab groups included upper respiratory infection, urinary tract infection and hyperuricemia. Interpretation: Tafolecimab dosed at 450 mg Q4W and 600 mg Q6W was safe and showed superior lipid-lowering efficacy versus placebo, providing a novel treatment option for Chinese hypercholesterolemia patients. Funding: This study was sponsored by Innovent Biologics, Inc