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Since permanent magnet direct current (DC) motors are mainly used in various industrial automation applications, the demand for electric motors is increasing rapidly. However, in the mass production of electric motors, often, only random inspections are used to check the specifications and performance of electric motors. For manufacturing or engineering application staff to have a more thorough understanding of the characteristics of the motor, it is necessary to conduct a full or quick inspection during the production process to ensure the quality of the electric motor. Based on this, this literature review reveals several methods and algorithms often used to estimate DC motor parameters, given the importance of knowing the parameters of the DC motor and the lack of research on estimating the parameters of the DC motor.

High efficiency tunneling oxide passivated contact (TOPCon) solar cell is the traditional PN junction structure, combined the advantages of using a thin film of the passivated silicon surface to separate the metal from the silicon wafer. In this study, the patent analysis of high efficiency TOPCon solar cell is presented. The structure and process technology of TOPCon solar cell were analyzed first, which is used as the basis for the key words of the patent search. The patent management chart analysis is provided, and then the patent portfolio of the main research countries and important manufacturers on the research subject can be recognized. Moreover, the technology-function matrix analysis is used to comprehend the technical development trend of the research topic. The results indicate the TOPCon solar cell technology currently entered into the maturity stage in 2019, and the companies with the top three number of patents are LG Electronics, SunPower, and SolarCity (which was acquired by Tesla in 2016). SunPowern is the earliest patent assignee, and LG Electronics is the follower, while its patent outputs are heavily concentrated after 2014. Patent technology-function matrix found the development focus of the device-related technologies are tunneling oxide and polycrystalline silicon, with a total of 21 patents, and the development focus of process-related technologies are the process of tunneling oxide layers and the process of polysilicon film. Based on the analysis results, the future development prospects of the research topic and the direction of patent portfolio are evaluated.

This paper presents the optimal design of in-plant logistics in manufacturing. Owing to rising energy costs and the supply-demand imbalance leading to price competition, resulting in a sharp decline in profit, business management is facing a severe test, especially heavy industry. In practice, the important decision-making in C Company has relied on expert experience and existing knowledge, the lack of systematic thinking, and technology applications, resulting in a waste of logistics costs. Therefore, a study on the application of genetic algorithms to optimize steel mill factory by-product transport and logistics is presented herein. The aim is to solve the bottleneck of traditional decision-making in order to achieve the goal of optimizing transportation logistics decision-making via artificial intelligence. In defining the problem, the model of the steel mill factory by-products transport and logistics is constructed through in-plant route information, vehicle routing systematization and consideration of the transport demand frequency. The modified variable length chromosome ending technique and bi-level genetic algorithm are used to effectively solve the problem of different zoning transportation on double layer genetic algorithm application. The results show that the total transport time is slightly better than the existing results.

Control design of power-assist systems has been widely applied to human-robot interactive systems such as wearable exoskeleton systems, of which the range of motion limitation of human joints in the power-assist systems is essential. This paper presents a virtual soft boundary design for a human-robot cooperation system with a limited operating range. The proposed virtual soft boundary is realized by impedance control and integrated into the power-assist robot arm system; meanwhile, power-assist robot arm systems are typical human-in-the-loop systems, and the control of the power-assist system in performing in accordance with a human’s perception is a significant issue. Therefore, a model-based disturbance observer with a pseudo-derivative feedback feedforward (PDFF) compensator is designed to effectively estimate the human’s torque for an appropriate motor torque command. Experimental results show that the proposed control method can estimate the human torque exerted on the robot arm system to achieve a power-assist system, and the virtual soft boundary can be realized by the impedance control and integrated into the power-assist robot arm system.

This paper investigates an active anti-vibration system, and the isolation of low-frequency vibration is studied. A model reference control of the anti-vibration system with a sky-hook damper and impedance control is analyzed. An illustrated example of a single-degree-of-freedom anti-vibration system driven by a tubular linear servomotor is given to verify the performance of the proposed control design. Experimental results are given to show that the peak resonance value of 0dB within a frequency of 10Hz can be achieved successively.

Background The appropriate limit to the amount of daily sedentary time (ST) required to minimize mortality is uncertain. This meta-analysis aimed to quantify the dose-response association between daily ST and all-cause mortality and to explore the cut-off point above which health is impaired in adults aged 18–64 years old. We also examined whether there are differences between studies using self-report ST and those with device-based ST. Methods Prospective cohort studies providing effect estimates of daily ST (exposure) on all-cause mortality (outcome) were identified via MEDLINE, PubMed, Scopus, Web of Science, and Google Scholar databases until January 2018. Dose-response relationships between daily ST and all-cause mortality were examined using random-effects meta-regression models. Results Based on the pooled data for more than 1 million participants from 19 studies, the results showed a log-linear dose-response association between daily ST and all-cause mortality. Overall, more time spent in sedentary behaviors is associated with increased mortality risks. However, the method of measuring ST moderated the association between daily ST and mortality risk ( p  < 0.05). The cut-off of daily ST in studies with self-report ST was 7 h/day in comparison with 9 h/day for those with device-based ST. Conclusions Higher amounts of daily ST are log-linearly associated with increased risk of all-cause mortality in adults. On the basis of a limited number of studies using device-based measures, the findings suggest that it may be appropriate to encourage adults to engage in less sedentary behaviors, with fewer than 9 h a day being relevant for all-cause mortality.

The power-dependent spectra and polarization of the second harmonic generation (SHG) in a III–V nitride semiconductor layer were analyzed in order to characterize the properties of the near-infrared femtosecond pulsed laser. The SHG spectrum can be used to connect the relation between the autocorrelation trace and spectrum of the pulsed laser, thereby correctly determining the peak power and pulse duration. This facile method can be readily used as a characterization tool for developing the low-cost femtosecond pulsed lasers.

Background: This meta-analysis aimed to estimate the shape of the dose-response association between objectively-assessed daily sedentary time (ST) and all-cause mortality, and to explore whether there is a threshold of ST above which there is an increase in mortality risk in older adults. Methods: Searches for prospective cohort studies providing effect estimates of daily ST (exposure) on all-cause mortality (outcome) were undertaken in five databases up to 31 March 2019. A random-effects meta-regression model was conducted to quantify the dose-response relationship between daily ST and all-cause mortality. Sensitivity analyses were also performed to test the stability of the results. Results: Our analysis of pooled data from 11 eligible studies did not reveal a consistent shape of association between ST and mortality. After excluding three studies with potential confounding bias, there was a log-linear dose-response relationship between daily ST and all-cause mortality. Overall, higher amounts of time spent in sedentary behaviors were associated with elevated mortality risks in older adults. Visual assessments of dose-response relationships based on meta-regression analyses indicated that increased mortality risks became significant when total ST exceeded approximately 9 h/day. Conclusions: Based on a limited number of studies, this meta-analysis provides a starting point for considering a cut-off of daily sedentary time, suggesting older adults spend less time in daily sitting.

國際身體活動指引建議成年人每週應進行至少150分鐘的中強度有氧運動，或至少75分鐘高強度有氧運動，或以相等活動量進行中高強度組合活動。但這易讓人感到輕度身體活動（如：散步、遛狗、逛街購物、輕度家務勞動等）似乎沒有健康益處。近年逐漸有研究指出：輕度身體活動可為成年人（含老年人）帶來健康效益。本篇綜論檢視了以儀器測量輕度身體活動和其健康有關研究的重要議題，並討論輕度活動對18歲以上成年人的健康益處是否被低估。首先，描述國際間有關客觀測量輕度身體活動的現況。其次，分析以儀器測量身體活動相關研究的系統性文獻回顧及統合分析等證據，探討輕度身體活動與死亡率、罹病率及其他健康狀態之關係。最後，討論輕度身體活動的健康效益是否被低估的議題。整體而言，系統性文獻回顧及統合分析均支持輕度身體活動可提供成年人健康益處，且此效益獨立於中高強度身體活動的影響。部分研究建議成年人每天至少從事6小時的輕度身體活動以獲得健康效益，但須更多研究加以驗證。