Search

This article proposes a rotor attitude estimation (RAE) method for spherical motors using the multiobject Kalman kernel correlation filter (MKKCF) algorithm in monocular vision. A permanent magnet spherical motor (PMSpM) is adopted as the research object, and a monocular area scan camera is equipped in the RAE system with a visual feature component mounted on top of the rotor output shaft. In the proposed MKKCF algorithm, the Kalman filter is used to enhance the robustness and accuracy of KCF tracker for each object. To simplify the proposed algorithm verification, a one-object tracking comparison is conducted among the KCF algorithm, the fast discriminative scale space tracking (FDSST) algorithm, and the Kalman KCF algorithm, and the results show that Kalman KCF tracker is more applicable for RAE. In addition, an RAE test bench is developed, and the MKKCF-based RAE method and the micro-electro-mechanical system (MEMS) (MPU9250) method are compared when estimating the rotor attitude. To set a benchmark, the contact rotor position measurement with encoders is used. The comparison results indicate that the MKKCF-based RAE method works with higher accuracy than the MEMS method. Finally, a closed-loop PMSpM control experiment is conducted by using the proposed MKKCF-based RAE method, and the practicability of the proposed method is proved. [ABSTRACT FROM AUTHOR]

A permanent magnet spherical motor (PMSpM) is a representative multiple degree-of-freedom electric apparatus. This paper proposes new analytical models for the PMSpM with stepped cylindrical permanent magnets (PMs). The research is not only to obtain the magnetic field and torque models of the PMSpM but also to yield a potential analytic tool for the spatial magnetic field and torque decomposition. The model decomposition aims to acquire a potential tool for the future research on PMSpM topology optimization and working mechanism. To achieve the two research targets above, the toroidal expansion method is used for magnetic field modeling, and the finite element method verification and experimental verification are conducted. Then, forces and torques are deduced from the Lorentz force law. In addition, a prototype PMSpM has been produced and the comparison studies of the air-gap flux density and torque among decomposed components are conducted using finite element analysis results and experimental results. It is concluded that the proposed analytical PMSpM models and the model decomposition method are proved. [ABSTRACT FROM AUTHOR]

This paper proposes a monolayer Halbach array based permanent magnet spherical motor (PMSpM) using cubic permanent magnets (PM). The research aims to provide a fast computing model to calculate the magnetic field for this PMSpM, which helps for future PMSpM optimization and control study. Three thickness equivalence principles are provided and compared for cubic PMs. The magnetic scalar potential is introduced, and the spherical harmonics expansion is implemented for rotor magnetic field analysis. Engineering revision is used to reduce the Legendre function deviation in polar angle direction. Torques and forces are deduced using the Lorentz force law, and relatively simple models of this PMSpM for both magnetic fields and torques are acquired. In addition, a prototype motor has been developed, and the analytic results of air-gap flux density and torque are compared with their finite element simulation and experimental results, which are proved consistent. It is concluded that the fundamental component of the spherical harmonics can be used to present the magnetic field model, which uses fewer integrals than the Biot-Savart law based solution, and the modeling results of the magnetic field flux density, forces and torques are in line with the expectations. The analytic models are proved correct. [ABSTRACT FROM AUTHOR]

In the last 20 years, humane education (HE) has undergone a paradigm shift from a simple animal welfare education model to a teacher-led positive education approach that cultivates kindness, love, and empathy in children and youth. While teachers' humane attitudes are considered a prerequisite for HE program success in school settings, their attitudes toward animals have received little attention to date. This study investigated pre-service teachers' humane attitudes toward animals and assessed whether and to what extent these attitudes are correlated with empathetic tendencies as well as variables such as gender and current and previous pet ownership. A total of 226 pre-service teachers in Hong Kong completed the Animal Attitude Scale (AAS) and the Davis Interpersonal Reactivity Index (IRI). The results showed that pre-service teachers showed moderate concern for the humane treatment of animals, and a difference in humane attitude was identified based on sex: female pre-service teachers tended to express more humane attitudes than their male counterparts. Moreover, pre-service teachers with greater tendencies toward warmth and compassion demonstrated a more welfare-oriented attitude toward animals. The results of the current study support using HE as a positive education approach and imply that the provision of training for pre-service teachers and teachers should be given higher priority by humane educators. Humane educators are recommended to recruit pre-service teachers as HE program instructors in their research projects. [ABSTRACT FROM AUTHOR]

We study the effect of political power on resource allocation for knowledge production dictated by central planning in a non-market system. Our empirical results suggest that, compared to non-connected scholars, political connected (PC) scholars have 15.7% more allocation granted by the national Natural Science Foundation of China (NSFC). Variations in grant allocation is related to weaker institutional environments, less reputable universities, and hard-to-value project. Additional analysis suggests that access to the NSFC fund not only benefits individual PC scholars in terms of their research quality, but also brings more high-impact publications for their affiliated institution. • Political connected (PC) scholars have 15.7% more allocation granted by NSFC. • Political favoritism is related to weaker institutional environment. • NSFC fund benefits political connected scholar's research quality. • NSFC fund brings high-impact publications for PC scholar's affiliated institution. [ABSTRACT FROM AUTHOR]

The thermal energy storage technology based on phase change materials (PCMs) can solve the mismatch problem between thermal energy supply and demand, and improve energy utilization efficiency. However, the fluid leakage problem and low thermal conductivity of PCMs are not suitable for solar thermal storage application. The solar thermal collector combined with PCM seeks for the rapid storage of thermal energy and reduces the heat exchange with external environment, requiring PCM to possess specific directional thermal conduction. In this paper, inspired by the principle of directional transport of water in the cellulose channel of natural trees, the porous structure with anisotropic thermal conductivity is formed by carbonization of pine at 1000 °C. The CPCM with directional thermal conductivity is prepared by combining magnesium nitrate hexahydrate (MNH) with carbonized wood (CW). The axial thermal conductivity of the MNH/CW composite PCM (CPCM) is 1.86 times than that of the radial direction. The photo-thermal conversion efficiency of MNH/CW CPCM is 83%. This structure changes the direction of thermal energy transmission, and reduces the dissipation of thermal energy and the use of thermal insulation medium. This work provides an innovative idea for the design and manufacture of CPCM related to low and medium temperature solar thermal energy storage. • The anisotropic thermal conductivity structure of CW is formed by carbonization. • The axial thermal conductivity is 1.86 times than that of radial direction. • The photo-thermal conversion efficiency of CPCM is 83%. [ABSTRACT FROM AUTHOR]

This article proposes a position detection method for a multi-to-one wireless power transmission (WPT) system for the first time and applies it to the position detection of a spherical motor. The traditional contact detection system has high friction resistance and poor rotor positioning accuracy. Although some noncontact measurement systems are not directly connected to the rotor, the structure or calculation of the measurement system is more complicated. To solve the abovementioned problems, this article proposes two structural topologies, which are evenly arranged on the upper part of the rotor and the receiving coil is placed on the rotor shaft. When the motor rotor rotates along with the three motion states of yaw, spin, and tilt, the receiving and multitransmitting coils will have an angular offset. The rotor position is obtained by a method of accurately estimating the mutual inductance. This method avoids complicated finite element calculations and saves a lot of time. Finally, the experiment verifies the above analysis and compares the data with the microelectromechanical system three-degree-of-freedom attitude detection method. This article provides insights into the position detection of spherical motors. This method simplifies the previous measurement system and obtains higher positioning accuracy. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive backstepping sliding mode control method based on a nonlinear disturbance observer (NDO) to solve the problem that the tracking performance of the motion system of a permanent magnet spherical motor (PMSpM) is degraded due to the influence of external nonlinear disturbance. First, the dynamic model of the PMSpM under the compound interference is established. Second, an NDO and an adaptive backstepping sliding mode controller are designed to compensate for the external disturbances and modeling uncertainties, and the stability of the closed-loop system using the proposed method is confirmed through the Lyapunov theorem. Then, compared with the results of proportion differentiation control and conventional sliding mode control, the simulation results show that the proposed method can significantly reduce input signal chattering and improve the trajectory tracking performance of the PMSpM. Finally, experimental results are provided to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease) is a neurodegenerative disease characterized by motor neuron degeneration, paralysis and death. One cause of this disease is mutations in the Cu,Zn superoxide dismutase (SOD1)gene. As mutant SOD1 acquires a toxic property that kills motor neurons, by reducing the mutant protein the disease progression may be slowed or prevented. While mutant SOD1 is toxic, the wild-type SOD1 is indispensable for motor neuron health. Therefore, the ideal therapeutic strategy would be to inhibit selectively the mutant protein expression. Previously we have demonstrated that RNA interference (RNAi) can selectively inhibit some mutant SOD1 expression. However, more than 100 SOD1 mutants can cause ALS and all mutants cannot be inhibited selectively by RNAi. To overcome this obstacle, we have designed a replacement RNAi strategy. Using this strategy, all mutants and wild-type genes are inhibited by RNAi. The wild-type SOD1 function is then replaced by designed wild-typeSOD1genes that are resistant to the RNAi. Here we demonstrate the concept of this strategy. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the innovative efficiency of SOEs in China. Innovative efficiency refers to output of patents per dollar spending of R&D expenditure. The data indicate that minority SOEs are substantially more innovatively efficient than non-SOEs and majority SOEs. The relative innovative efficiency of minority SOEs is more pronounced among firms with high financial constraints. The data are consistent with the view that, in the Chinese context, there are favorable benefits to partial state ownership through access to talent, connections, and technological resources that enable efficient patent outcomes from R&D expenditure. • We investigate the innovative efficiency (patents per dollar spending of R&D expenditure) of Chinese SOEs. • We show minority SOEs are substantially more innovatively efficient than non-SOEs and majority SOEs. • The relative innovative efficiency of SOEs is more pronounced among firms with high financial constraints. [ABSTRACT FROM AUTHOR]

To mirror an important aspect of ultra-high voltage network development, the remarkable amount of energy cost and carbon emissions of a typical ultra-high voltage transformer substation in China is revealed, in light of the hybrid method as the integration of input-output analysis and process analysis. By inclusively inventorying all the input items as products of the economy, the study differs from previous studies that simply treat the input items as some primary materials. The results show that the total energy cost and carbon emissions of 1000 kV transformer substation are 6.82E+09 MJ and 7.12E+05 t CO 2 eq., respectively. Equipment purchasing contributes more than 80% to the overall energy cost and carbon emissions, followed by construction engineering, additional service and installation engineering. From the sectoral perspective, Manufacture of equipment for power transmission and distribution and control sector (Sector 78) dominates the energy cost and carbon emissions induced by 1000 kV transformer substation, followed by Construction industry (Sector 95). The comparison and analysis between current research and previous studies in different countries and different voltages is clearly discussed. This study not only enhances our understanding about the impact of ultra-high voltage network on energy and environment, but also provides insights for energy conservation and low carbon development. [ABSTRACT FROM AUTHOR]

Rapid urbanization drives the expansion of urban power girds, which involves enormous energy intensive products such as steel and concrete and inevitably results in a great quantity of carbon emissions. However, little has been done to investigate urban power girds' impact on carbon emissions. To solve this problem, this study makes efforts to calculate the carbon emissions of urban power grid in Jing-Jin-Ji region, one of the most populous and economically dynamic regions in China, in light of the hybrid method. Moreover, the depreciation life of urban power grids is taken into consideration for the first time, which avoids the underestimation of the accumulated carbon emissions of urban power grid due to depreciation. The results show that the accumulated carbon emissions of urban power grid in Jing-Jin-Ji region are 2.71E+06 t CO 2 eq. in 1993. When it comes to 2014, this figure increases by over 7.2 times. The majority of the carbon emissions by typical urban substations and transmission line projects are contributed by electrical equipment, steel and construction industries. 4 scenarios are set to predict the future carbon emissions by power grids in Jing-Jin-Ji region. The highest accumulated carbon emissions in 2020 are projected to be 7.63E+07 t CO 2 eq. under the condition shortest depreciation life (SDL) in the First Year Finished (FYF) scenario. Regression analysis is also carried out to show some influential factors such GDP's influence on power grids' carbon emissions, suggesting that the correlation between carbon emissions and regional economic development becomes more significant after Power System Reform Plan in 2002. This study not only draws a holistic picture of power grid but also bears significance to policies and actions in urban regions. [ABSTRACT FROM AUTHOR]

China implemented the Promoting the Big and Quashing the Small Policy (PBQSP) in 2007 to alleviate air pollution due to coal-fired power plants (CFPPs). However, how the policy affected the air pollutant emissions remains poorly understood. We compared the air pollutant emissions between decommissioned and newly-built CFPPs under the PBQSP by developing a plant-level supply chain emission inventory model, taking Shandong, China's top provincial-level coal power producer, as the case area. The results indicated that compared to a 27.4% increase in electricity produced in Shandong from 2010 to 2014, the NOx, particulate matter (PM), Hg, and SO 2 emissions disproportionately increased by 10.3%, 11.7%, 11.8% and 0.5%, respectively. It was found that the PBQSP policy has made great contribution to air pollution mitigation, as the supply chain emission intensities (emissions per kilowatt-hour) of NO X , PM, Hg and SO 2 of the newly-built CFPPs are three-quarters, two-fifths, three-fifths, and four-fifths lower, respectively, than those of the decommissioned CFPPs. However, coal transport route changes caused an increase in NO X , PM, and SO 2 emissions by 44.0%, 45.5%, and 55.6%, respectively, during the transportation stage, which offset the PBQSP overall mitigation effect. By building a comprehensive assessment framework for air pollutant control policies, our study provides insights for formulating coordinated mitigation measures for the pollutant-intensive industries, such as promoting efficient air pollutant control technologies including the spray dust suppression devices. • A supply chain emission inventory model was built to assess the mitigation effect. • Technological improvement led to the decline of the emission intensity. • The coal transport route changes resulted in a net increase in air pollutants. • Policy implications for comprehensive pollutant mitigation were recommended. [ABSTRACT FROM AUTHOR]

Background/Aims: Integrin activation and lymphocyte migration to the vascular intima is a key event in early atherosclerosis. α4β7 integrin (LPAM-1) and its ligand, mucosal addressin cell adhesion molecule (MAdCAM-1) are known to play an important role in homing of activated lymphocytes to gut-associated lymphoid tissues. However, it is unclear whether α4β7 integrin is involved in the pathogenesis of atherosclerosis. Methods: The expressions of α4β7 integrin and its ligands in atherosclerosis plaques from 12 week high fat diet (HFD) fed ApoE-/- and C57BL/6 mice were examined using immunofluorescent and immunohistochemical assays, respectively. We also generated ApoE/β7 double deficient mice and compared atherosclerotic lesion development in β7+/+ApoE-/- and β7-/-ApoE-/- mice that were fed with HFD for 12 weeks. Results: We found an upregulation of α4β7 integrin and its ligands VCAM-1 and MAdCAM-1 at atherosclerosis plaques in Apolipoprotein E deficient (ApoE-/-) mice fed with HFD for 12 weeks. Over the 12 week HFD period, peripheral blood lymphocyte (PBL) expression of α4β7 integrin increased in parallel with aortic lesion size. A removal of α4β7 integrin by genetic deletion of the β7 chain in the ApoE-/- mouse resulted in a markedly decreased 12 week-HFD atherosclerotic plaque area. β7-/- ApoE-/- macrophages showed reduced acetylated and native LDL uptake and phagocytic activity, revealing possible roles for α4β7 at two distinct stages of macrophage dysfunction during atherogenesis. Finally, a reduced activity of integrin downstream signalling components focal adhesion kinase (FAK) and MAPK/ERK1/2 in macrophage indicates their possible engagement during α4β7 integrin signalling in atherosclerosis. Conclusions: Together our results reveal a critical role of α4β7 in diet-induced atherosclerosis in mouse. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Presents corrections to the article "An RNAi Strategy for Treatment of Amyotrophic Lateral Sclerosis Caused by Mutant Cu,Zn Superoxide Dismutase," which was published in a previous issue of the "Journal of Neurochemistry."

The Toll family of receptors is required for innate immune response to pathogen-associated molecules, but the mechanism of signaling is not entirely clear. In Drosophila the prototypic Toll regulates both embryonic development and adult immune response. We demonstrate here that the host protein Spätzle can function as a ligand for Toll because Spätzle forms a complex with Toll in transgenic fly extracts and stimulates the expression of a Toll- dependent immunity gene, drosomycin, in adult flies. We also show that constitutively active mutant of Toll form multimers that contain intermolecular disulfide linkages. These disulfide linkages are critical for the activity of one of these mutant receptors, indicating that multimerization is essential for the constitutive activity. Furthermore, systematic mutational analysis revealed that a conserved cysteine-containing motif, different from the cysteines used for the intermolecular disulfide linkages, serves as a self- inhibitory module of Toll. Deleting or mutating this cysteine- containing motif leads to constitutive activity. This motif is located just outside the transmembrane domain and may provide a structural hindrance for multimerization and activation of Toll. Together, our results suggest that multimerization may be a regulated, essential step for Toll-receptor activation. [ABSTRACT FROM AUTHOR]