ObjectiveWe conducted a systematic review and meta-analysis to evaluate the prospective effect of adverse work-related psychosocial factors on increases in inflammatory markers. MethodsA systematic literature search was conducted in PubMed, Embase, PsycINFO, PsycARTICLES, and the Japan Medical Abstracts Society database. Studies were eligible for inclusion if they examined associations between work-related psychosocial factors and inflammatory markers (interleukin-6, tumor necrosis factor-alpha, and C-reactive protein), used longitudinal or prospective cohort designs, were conducted among workers, were original articles written in English or Japanese, and were published up to 2017 for the first search, October 2020 for the second, and November 2022 for the third. A meta-analysis was conducted using a random-effects model to assess the pooled effect size for the associations. A meta-regression analysis was used to estimate the association between length of follow-up and effect size. The ROBINS-I tool was used to assess risk of bias. ResultsOf the 11,121 studies identified in the first search, 29,135 studies from the second, and 9448 studies from the third, eleven were eligible for this review and meta-analysis. The pooled coefficient between adverse work-related psychosocial factors and inflammatory markers was significant and positive (β = 0.014, 95% confidence interval: 0.005–0.023). However, a clear association was only observed for interleukin-6, and all the studies included had serious risks of bias. Meta-regression showed the effect size decreased depending on the follow-up period. ConclusionThis study revealed a weak positive association between adverse work-related psychosocial factors and increases in inflammatory markers.Trial registration: PROSPERO CRD42018081553 (https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=81553).

Smaller and more efficient EV-motor control is accelerating, and IGBT packaging that controls motor driving is evolving remarkably. In particular, IGBT continues to invest in developing compact, high-efficiency packages with a capacity of 100kW or less. For this reason, DC/AC characterization at high power as well as thermal measures affecting efficiency has been incorporated in mass production sites. This paper summarizes the degree of influence of the contactor of the device on stray inductance measurement of IGBT module, and how much the influence can be reduced to measure stray inductance of the module itself with high reliability. Improved yield loss by contact failure is also described.

One of the causes of torque ripple in a motor is the harmonic current. To minimize the harmonic current, we focused on minimizing the inductance harmonics in this study. The stator core shape that reduced the inductance harmonics was identified using a topology optimization algorithm. A subsequent sensitivity analysis of the stator core shape with respect to the inductance harmonics yielded preliminary evaluation shapes. Experimental assessment of the evaluation shapes verified the reduction of the harmonic current and, therefore, the torque ripple.

This study verifies the effectiveness of a dynamic resonant frequency control system for transducers. This system enables the resonant frequency of the transducer to match the driving frequency. In general, the resonant frequency of an ultrasonic transducer is fixed based on its design and material properties. Therefore, it is difficult to actively control the frequency when driving the transducer. However, for high-power piezoelectric actuators, it is important to control the ratio of the fundamental and higher-order resonant frequency of the longitudinal vibration precisely at 1:2. A high-power and high mechanical quality factor (high-Q) ultrasonic transducer requires precise control of its resonant frequency. However, the resonant frequency may shift due to changes in boundary conditions or non-linear phenomena in piezoelectric vibration while driving the ultrasonic transducer. To maintain the resonant frequency ratio of the ultrasonic transducer at 1:2, we propose to dynamically control the resonant frequency ratio constant. In this study, we made two main proposals to our dynamic resonant frequency control system. One is the stepped structure of the transducer, and the other is the completely automatic control. In the stepped structure, a Langevin transducer was designed to have a resonant frequency ratio of almost 1:2 for the first and third longitudinal mode in the initial condition. Additionally, this structure could achieve control of only one of two resonant frequencies of the transducer. For the utterly automatic control system, piezoelectric elements were introduced for controlling the resonant frequency ratio precisely. For this propose, switching the electrical boundary conditions of these piezoelectric elements was carried out by MOSFETs connected to the ultrasonic transducer and control its optimum duty ratio automatically by our feedback system. This system realized dynamic control of the resonant frequency. As a result, the resonant frequency of the transducer matched the driving frequency in the frequency band from 23.23 kHz to 23.93 kHz. It was also confirmed that the shape of the excited non-sinusoidal waveform could be controlled by using resonant frequency control.

The United States has been at the forefront of developing energy regulations for over four decades. During this time, a Process Rule has been used to create dozens of regulations. This chapter examines how the Process Rule works today, including the various stakeholders typically involved in developing MEPS, rules for developing regulations, and efforts underway to improve the existing process. The chapter also includes two examples of regulations and the outcome of each. Finally, the chapter lists benefits by incorporating the Process Rule as a model.

The size-unified SEMI standard for PLP was adopted last year. And several package vendors have been developing processes for the practical application of PLP substrates. [1] We apply the capacitive test technique as a RDL first interconnect inspection on PLP package. [2] Though this inspection technology, we can judge defects such as fine voids of 20um or less in the real system. A calibration is effective in further improvement of the accuracy, such as dispersion correction by warpage of the panel and packages, etc. In this paper, the effect of correction is algebraically treated by using the capacity model of RDL in order to increase the accuracy of the inspection system. And, this paper carries out the analysis on the defect detecting accuracy using the characteristic data in the actual glass carrier panel, and the practical application is discussed. In this paper, the effect of correction is algebraically treated by using the capacity model of RDL in order to increase the accuracy of the inspection system. And, this paper carries out the analysis on the defect detecting accuracy using the characteristic data in the actual glass carrier panel, and the practical application is discussed.

Data-driven analysis of dynamic performance has attracted a lot of interest in the modern power grid with highly accurate measurement technologies such as Synchrophasor. In this chapter, we report the research effort to do this for voltage dynamics in a rudimentary model of power grids. We use the combination of the so-called delay embedding with the extended dynamic mode decomposition, which is a technique for approximating the Koopman operator directly from time-series data. This combination enables us to approximate the spectral properties of the Koopman operator through voltage–amplitude measurement of a single bus. The spectral properties clarify not only the local information on the voltage dynamics such as frequency/damping in transient responses but also global one such as the flow structure of the underlying mathematical model.

This paper introduces the test technology of redistribution layer used in FOPLP. In order to lower costs, FOPLP needs to adopt the RDL first process. In addition, it is necessary to guarantee that the package such as 2.5D that formed RDL is non-defective before mounting ICs. Since RDL is mounted on a carrier such as glass, double-sided inspection of the package becomes difficult. It is capacity inspection that can be proposed as this solution. In our work, we have improved the micro capacity tester to the accuracy below femto farad. Using this tester, we have demonstrated defect detection between RDL vias, formation defects of plating etc., in the package manufactured in an actual process. This method also allowed us to consolidate probing on one side. We introduce technologies for solving 40 um fine pitched micro pad probing problems as well as achieving a lower cost of test for a line and space 2/2 um FOPLP.

AbstractTo improve noise and vibration of Electric Power Steering (EPS) system, we focus on the reduction of the sixth‐order radial force of an EPS motor by regulating its harmonic current. Because an EPS system is operated in a wide speed range, a reduction method is required to work even for dynamic motor speed. In this article, we introduce our method and report its test result to show the reduction of sixth‐order radial vibration of an EPS motor.

We report the development of a millimeter-wave electron-spin-resonance (ESR) measurement system at the University of Fukui using a 3He/4He dilution refrigerator to reach temperatures below 1 K. The system operates in the frequency range of 125–130 GHz, with a homodyne detection. A nuclear-magnetic-resonance (NMR) measurement system was also developed in this system as the extension for millimeter-wave ESR/NMR double magnetic-resonance (DoMR) experiments. Several types of Fabry–Perot-type resonators (FPR) have been developed: A piezo actuator attached to an FPR enables an electric tuning of cavity frequency. A flat mirror of an FPR has been fabricated using a gold thin film aiming for DoMR. ESR signal was measured down to 0.09 K. Results of ESR measurements of an organic radical crystal and phosphorous-doped silicon are presented. The NMR signal from 1H contained in the resonator is also detected successfully as a test for DoMR.