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With the development of modern data collection techniques, researchers often encounter high-dimensional data across various research fields. An important problem is to determine whether several groups of these high-dimensional data originate from the same population. To address this, this paper presents a novel k-sample test for equal distributions for high-dimensional data, utilizing the Maximum Mean Discrepancy (MMD). The test statistic is constructed using a V-statistic-based estimator of the squared MMD derived for several samples. The asymptotic null and alternative distributions of the test statistic are derived. To approximate the null distribution accurately, three simple methods are described. To evaluate the performance of the proposed test, two simulation studies and a real data example are presented, demonstrating the effectiveness and reliability of the test in practical applications. [ABSTRACT FROM AUTHOR]

For high-dimensional two-sample Behrens–Fisher problems, several non-scale-invariant and scale-invariant tests have been proposed. Most of them impose strong assumptions on the underlying group covariance matrices so that their test statistics are asymptotically normal. However, in practice, these assumptions may not be satisfied or hardly be checked so that these tests may not be able to maintain the nominal size well in practice. To overcome this difficulty, in this paper, a normal reference scale-invariant test is proposed and studied. It works well by neither imposing strong assumptions on the underlying group covariance matrices nor assuming their equality. It is shown that under some regularity conditions and the null hypothesis, the proposed test and a chi-square-type mixture have the same normal and non-normal limiting distributions. It is then justifiable to approximate the null distribution of the proposed test using that of the chi-square-type mixture. The distribution of the chi-square type mixture can be well approximated by the Welch–Satterthwaite chi-square-approximation with the approximation parameter consistently estimated from the data. The asymptotic power of the proposed test is established. Numerical results demonstrate that the proposed test has much better size control and power than several well-known non-scale-invariant and scale-invariant tests. [ABSTRACT FROM AUTHOR]

The separator, as an important inner part of the sodium‐ion battery (SIB), has a significant impact on the electrochemical performance and security of the battery. However, conventional polyolefin separators are inapplicable for SIBs due to their poor wettability to liquid electrolytes and unsatisfactory heat resistance. To address these problems, a novel polyethylene (PE)‐ hydroxyethyl cellulose (HEC)‐TiO2 composite separator modified on the PE matrix is proposed and successfully prepared by a multistep synthesis procedure of HEC coating and TiO2 in situ self‐growth, while almost maintaining the initial separator thickness. Compared with conventional PE separators, this composite separator possesses remarkable wettability which benefits from the introduction of a polar HEC‐TiO2‐incorporated coating. Besides, thanks to a significant improvement in wettability, the separator presents high electrolyte uptake of up to 186.5% and an extraordinary ionic conductivity of 0.342 mS cm−1. As expected, a Na|Na3V2(PO4)3 battery with the PE‐HEC‐TiO2 separator exhibits a reversible capacity of 99.0 mAh g−1 and a capacity retention of 94.8% after 1000 cycles at 5 C with a steady Coulombic efficiency of nearly 100%. These brilliant performances convincingly make it a promising separator for advanced SIBs with high reversibility, high capacity, and long life. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries receive widespread attention in the past decade as a result of their high theoretical specific capacity. However, the shuttle effect of soluble polysulfides produced in the battery cycle can result in low sulfur utilization and slow reaction kinetics, which seriously hinders its practical application. Herein, a carrageenan (CG)–acetylene black (AB)‐modified separator for long‐life Li–S batteries is proposed. The batteries with modified separator exhibit excellent electrochemical performance, fast redox kinetics (733 mAh g−1 at 6 C), and a low‐capacity decay of 0.042% per cycle at 2 C. More importantly, a high reversible capacity of 805 mAh g−1 can be obtained at a high sulfur loading of 3.2 mg cm−2. The performance improvement of the separator can be attributed to the outstanding adsorbing polysulfides ability of CG and the better conductivity of AB. Combined with the natural source of CG, simple preparation process, and excellent electrochemical performance, our research results provide a kind of Li–S batteries promising modification idea. [ABSTRACT FROM AUTHOR]

While Product-Service Systems (PSS) have a potential sustainability impact by increasing a product's life and reducing resource consumption, the lack of ownership might lead to less responsible user behavior. Smart PSS can overcome this obstacle and guarantee correct and safe PSS use. In this context, intelligent connected vehicles (ICVs) with PSS can effectively reduce traffic accidents and ensure the safety of vehicles and pedestrians by guaranteeing optimal and safe vehicle operation. A core subsystem to support that is the collision-warning system (CWS). Existing CWSs are, however, limited to in-car warning; users have less access to the warning information, so the result of CWS for collision avoidance is insufficient. Therefore, CWS needs to be extended to include more elements and stakeholders in the collision scenario. This paper aims to provide a novel understanding of extended CWS (ECWS), outline the conceptual framework of ECWS, and contribute a conceptual modeling approach of ECWS from the smart PSS perspective at the functional level. It defines an integrated solution of intelligent products and warning services. The function is modeled based on the Theory of Inventive Problem Solving (TRIZ). Functions of an ECWS from the perspective of smart PSS can be comprehensively expressed to form an overall solution of integrated intelligent products, electronic services, and stakeholders. Based on the case illustration, the proposed method can effectively help function modeling and development of the ECWS at a conceptual level. This can effectively avoid delays due to traffic accidents and ensure the safety of vehicles and pedestrians. [ABSTRACT FROM AUTHOR]

The energy density of lithium cobalt oxide (LiCoO2)‐based cells can be increased by charging at voltages above 4.2 V. However, the poor interface stability of the cathode/electrolyte deriving from the continuous severe decomposition of the electrolyte on the cathode/electrolyte surface and the instability of the structure of the cathode at high‐voltage operation limits their wider commercial application. Herein, a new fluoro‐functionalized electrolyte additive, tetrafluoroethane beta‐sultone (TFBS), is used for promoting the electrochemical performance of LiCoO2‐based cells. Upon cycling between 3.0 and 4.5 V (vs. Li/Li+) with 0.5 C (1 C=274.4 mAh/g), it is shown that the capacity retention of the LiCoO2/graphite pouch‐cell with TFBS‐controlled electrolyte reaches 96.8 % (183.9 mAh g−1), yet it is 66.5 % (126.3 mAh g−1) for the pouch‐cell without TFBS in baseline electrolyte at the 100th cycle. All the results indicate that TFBS can be decomposed prior to the solvents in the electrolyte and can then form low‐resistance, high‐conductivity interface layers on the surfaces of the cathode‐electrolyte and the anode‐electrolyte, respectively, thus improving the cycling stability of the cells at a high charging cutoff voltage (4.5 V). [ABSTRACT FROM AUTHOR]

SUMMARY: A Pneumatic Muscle Actuator (PMA) is a new pneumatic component sharing similar characteristics with biological muscles, and the flexible manipulator actuated by PMAs can better reflect the flexibility of the mechanism. First and foremost, based on the study of the characteristics of human shoulder joints, the configuration design of the flexible manipulator is analyzed, and its kinematics and dynamics models are established. Furthermore, with regard to the nonlinearity, time-invariance and uncertainty of the control system, three aspects of improvement are proposed, which are based on the Radial Basis Function (RBF) network torque control algorithm. The Genetic Algorithm is used to optimize the initial values of RBF network parameters; RBF network parameters are adjusted dynamically by using the additional momentum method; the Levenberg--Marquardt (LM) algorithm, instead of the gradient descent method, is adopted to adjust Proportion Integration Differentiation (PID) parameters online in real time. At last, to test the effects that the improved algorithm exerts on the flexible manipulator control system, some physical platform experiments are carried out. It turns out that the control accuracy and robustness of the improved algorithm are well improved, and the mechanism can be controlled better to track the circular arc trajectory. It lays fundamental importance to the practical application for the working environment. [ABSTRACT FROM AUTHOR]

Today, the commercial application of silicon oxides (SiO x , 1 < x < 2) in lithium-ion batteries (LIBs) still faces the challenge of rapid performance degradation. In this work, by integrating hydrothermal and physicomechanical processes, water-soluble locust bean gum (LBG) and xanthan gum (XG) are utilized to in situ form an LBG@XG binder network to improve the performance of SiO x /C anodes. As a synergy of LBG and XG polysaccharides in hydrogel polymerization, LBG@XG can tightly wrap around SiO x /C particles to prevent plate damage. The flexible SiO x /C anode with the LBG@XG binder exhibits capacity retentions of 74.1% and 76.4% after 1000 cycles at 0.5 A g -1 and 1 A g -1 , respectively. The full battery capacity remains stable for 100 cycles at 1 C and the rate performance is excellent (103 mAh g -1 at 3 C). This LBG@XG is demonstrated to be highly electronegative and has a strong attraction to SiO x /C particles, thereby reducing the expansion and increasing the stability of the SiO x /C anodes when coupled with the flexible binder network. In addition to the promising LBG@XG binder, this work also provides a research idea for developing green water-based binders suitable for application in the SiO x /C anodes of LIBs.

For high-dimensional two-sample Behrens-Fisher problems, several non-scale-invariant and scale-invariant tests have been proposed. Most of them impose strong assumptions on the underlying group covariance matrices so that their test statistics are asymptotically normal. However, in practice, these assumptions may not be satisfied or hardly be checked so that these tests may not be able to maintain the nominal size well in practice. To overcome this difficulty, in this paper, a normal reference scale-invariant test is proposed and studied. It works well by neither imposing strong assumptions on the underlying group covariance matrices nor assuming their equality. It is shown that under some regularity conditions and the null hypothesis, the proposed test and a chi-square-type mixture have the same normal and non-normal limiting distributions. It is then justifiable to approximate the null distribution of the proposed test using that of the chi-square-type mixture. The distribution of the chi-square type mixture can be well approximated by the Welch-Satterthwaite chi-square-approximation with the approximation parameter consistently estimated from the data. The asymptotic power of the proposed test is established. Numerical results demonstrate that the proposed test has much better size control and power than several well-known non-scale-invariant and scale-invariant tests., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2020 Informa UK Limited, trading as Taylor & Francis Group.)

Parathyroid adenoma can cause primary hyperparathyroidism. Too much parathyroid hormone effects on bone, kidney and small intestine, which can cause parathyroid hormone, serum calcium, urine calcium and serum alkaline phosphatase elevated, while serum phosphate decreased. Clinical manifestations of osteoporosis, kidney stones, high calcium crisis and a serise of performance. There were 2 cases suffered from parathyroid adenoma and parathyroid hyperfunction in our hospital from December 22,2010 to March 11,2011. Surgical operation is the best treatment method.