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This exploratory paper aims to examine attitudes and practices with regard to the COVID-19 pandemic, as well as the effects of mandatory teleworking from home in the wake of the first state of emergency orders in Japan in 2020.

An online survey of married employees retrospectively assessed changes in work style, subjective well-being, work–family conflict and job performance before and during forced teleworking from home in Tokyo and three of the surrounding prefectures.

Regular employees reported high levels of anxiety and to have thoroughly implemented government-recommended hygiene and safety practices. A majority of respondents were satisfied with mandatory telework from home and desired to continue partial telework after the end of the pandemic. The strongest predictor of satisfaction with mandatory telework from home turned out to be adequate workspace at home for both men and women. However, the antecedents of the desire to continue working from home differed by gender.

These findings can help individuals, firms and governments better understand the effects of mandatory teleworking from home and devise countermeasures to maximize employee well-being and job performance. This is all the more crucial, as Japan has had successive waves of the virus and has declared numerous states of emergency since the beginning of the pandemic, forcing office workers to continue social distancing and remote working for the time being.

To the best of the authors’ knowledge, this research is one of the first to provide insights on how imposed teleworking from home in the context of COVID-19 in Japan affected regular employees’ personal and professional lives and to identify predictors of satisfaction with teleworking and the desire to continue doing so.

The purpose of this paper is to investigate the fatigue behavior of precipitation-strengthened Cu‒2.55Ni‒0.55Si alloy, modified by the addition of 0.25 Cr and 0.25 Zr (wt%), using mechanical and fractographical studies to reveal the effect of microstructural features on the fracture.

For strengthening, cast and hot forged alloy was subjected to solution annealing at 900°C for 60 min, followed by quenching in water and then aging at 490°C for 180 min. Precipitation-hardened alloy was exposed to fatigue tests at R=−1 and different stress levels. All fracture surfaces were examined within the frame of fractographical analysis.

Fine Ni-rich silicides responsible for the precipitation strengthening were observed within the matrix and their interactions with the dislocations at lower stress level resulted in localized shearing and fine striations. Although, by the addition of Cr and Zr, the matrix consisted of hard Ni, Zr-rich and Cr-rich silicides, these precipitates adversely affected the fatigue behavior acting as nucleation sites for cracks.

These findings contribute to the present knowledge by revealing the effect of microstructural features on the mechanical behavior of precipitation-hardened Cu‒Ni‒Si alloy modified by Cr and Zr addition.

The purpose of this paper is to examine from the viewpoint of resource utilization the Japanese surgical payment system which was revised in April 2016.

The authors collected data from surgical records in the Teikyo University electronic medical record system from April 1 till September 30, 2016. The authors defined the decision-making unit as a surgeon with the highest academic rank in the surgery. Inputs were defined as the number of medical doctors who assisted surgery, and the time of operation from skin incision to closure. An output was defined as the surgical fee. The authors calculated each surgeon’s efficiency score using output-oriented Charnes–Cooper–Rhodes model of data envelopment analysis. The authors compared the efficiency scores of each surgical specialty using the Kruskal–Wallis and the Steel method.

The authors analyzed 2,558 surgical procedures performed by 109 surgeons. The difference in efficiency scores was significant (p = 0.000). The efficiency score of neurosurgery was significantly greater than obstetrics and gynecology, general surgery, orthopedics, emergency surgery, urology, otolaryngology and plastic surgery (p<0.05).

The authors demonstrated that the surgeons’ efficiency was significantly different among their specialties. This suggests that the Japanese surgical reimbursement scales fail to reflect resource utilization despite the revision in 2016.

A new aramid base material for use in laminates to be applied to advanced surface mount technology was developed. A new fibre based on PPDETA (Poly‐p‐phenylene/3,4'‐diphenylether terephthalamide) was found to have negative thermal and hygroscopic expansion coefficients, low ionic impurities and high affinity to epoxy and polyimide resins. The fibre was processed into fabrics and papers to be used as a base material for printed circuit boards for advanced surface mount technology. Impregnation with a new epoxy resin with high purity and high temperature resistance implemented the development of a new laminate with minimal electromigration and high dimensional stability. Thus, a new laminate was developed to be used for LCCC, PGA, COB, TAB, Flip‐Chips and other advanced surface mount technologies. Reliability of the laminate to electromigration between surface conductors, between plated‐through barrels, and between opposed conductors was found to be one of the highest available today. These types of behaviour were related to the high purity and high temperature resistance of both the reinforcement material and the resin. The short life of through‐hole plating in thermal shock was improved by the application of a new plating technology. Application to multilayer boards and laminates with a low dielectric constant is also being investigated.

The purpose of this paper is to develop a ferromagnetic needle adaptable for a novel ablation cancer therapy; the heat generation ability of the mild steel rod embedded into the Ti‐tube having a different thickness was investigated in a high‐frequency output at 300 kHz.

The outer diameter and length of the Ti‐tubes were 1.8 and 20 mm, respectively, while the inner diameter was varied from 1.6 to 0 mm. The mild steel rod was embedded in a Ti‐tube for preparing the needle‐type specimen. Their heat generation ability was examined by changing the inclination angle to the magnetic flux direction in a high‐frequency coil.

When the thickness of the Ti surrounding the mild steel rod was as low as 0.1 mm, the heat generation ability was drastically different among the three inclination angles (θ=0°, 45°, and 90°) to the magnetic flux direction due to the effect of the shape‐induced magnetic anisotropy. However, the effect of the inclination angle was almost eliminated in the specimen surrounded by the 0.4 mm thick Ti, suggesting that the non‐oriented heat generation property is achieved for the needle‐type mild steel rod coated with Ti having the optimum thickness.

The prototype ablation needle having a complete non‐oriented heat generation ability was fabricated to use in subsequent animal experiments. It is considered that the newly designed Ti‐coated device is useful in ablation treatments using a high‐frequency induction heating.

The purpose of this paper is to examine the association between outpatient orthopedic surgery costs and Japan’s healthcare facilities using a large-scale Japanese medical claims database.

The authors obtained reimbursement claims data for 8,588 patients who underwent orthopedic surgery between April 1 and September 30, 2014 at 3,347 Japanese healthcare facilities. Regression analysis, using ordinary least squares, examined the association between outpatient orthopedic surgery costs and healthcare facility characteristics. By using surgical fees as proxy for the surgical costs, the authors defined three dependent variables: surgical cost for each outpatient orthopedic surgery; pre- and post-operative cost one month before and after a surgical operation; and total cost for each patient. The authors also defined five independent variables, which capture healthcare facility characteristics and patient-specific factors: bed count; whether healthcare facilities are reimbursed in a diagnosis procedure combination system; patient’s age; sex; and anatomical surgical sites.

The authors analyzed 6,456 outpatient orthopedic surgical cases performed at 3,085 healthcare facilities. There were significant differences in the surgical costs for outpatient orthopedic surgery among different healthcare facilities by total beds (p=0.000). Multivariate regression analysis shows that surgical costs for outpatient orthopedic surgery are positively and significantly associated with healthcare facilities classified by total beds after adjusting for patient-specific characteristics (p<0.05).

This is the first research to examine the association between costs for outpatient orthopedic surgery and healthcare facility characteristics in Japan. This study via the multivariate regression method showed that outpatient orthopedic surgery is likely to cost higher as healthcare facility size increased. The average incremental costs for each outpatient orthopedic surgery per 100 beds were calculated at $48.5 for surgery, $40.7 for pre- and post-operative care, and $89.2 total cost.

It is important to investigate large‐scale numerical analyses of electromagnetic fields in design processes of electromagnetic machines. Thus, faster solvers for eddy current analyses are necessary. Parallel computation methods for linear solvers in electromagnetic field analyses have been investigated. These methods have gained importance due to the diffusion of PC clusters and multi‐core CPUs in recent years.

This paper discuses linear solvers for the finite element method in eddy current analyses on parallel computers. The preconditioned conjugate gradient method with overlapping domain decomposition is treated. Some techniques treated to improve the convergence was investigated.

The numerical results show that the overlapping effect results in good convergence in eddy current analyses.

The preconditioned conjugate gradient method with overlapping domain decomposition has been treated. The numerical results show that the overlapping method works more efficiently for eddy current analyses. Moreover, this method enables large‐scale analyses on popular computers such as PC clusters.

The sustainability of the Japanese healthcare system is in question because the government has had a huge fiscal debt. Despite an enormous effort to cut the deficit, our healthcare expenditure is increasing every year because of the rapidly aging population. One of the solutions for this problem is to improve the productivity of healthcare. The purpose of this paper is to determine the factors that change surgeons’ productivity in one year.

The authors collected data of all surgical procedures performed at Teikyo University Hospital from April 1 through September 30 in 2014 and 2015, and computed the surgeons’ Malmquist index (MI), efficiency change (EC) and technical change (TC) using non-radial and non-oriented Malmquist model under the constant returns-to-scale assumptions. The authors then divided the surgeons into two groups; one whose productivity progressed and the other whose productivity regressed. These two groups were compared to identify factors that may influence their MI.

The only significant difference between the two groups was ECs (p < 0.0001). The other factors, such as TC, experience, surgical volume, emergency cases, surgical specialty, academic ranks, medical schools and gender, were not significantly different between the two groups.

EC is a major determinant of surgeons’ productivity change. The best way to improve surgeons’ productivity may be to enhance their efficiency regardless of their surgical volume and personal backgrounds.

The purpose of this paper is to examine whether the current surgical reimbursement system in Japan reflects resource utilization after the revision of fee schedule in 2014.

The authors collected data from all the surgical procedures performed at Teikyo University Hospital from April 1 through September 30, 2014. The authors defined the decision-making unit as a surgeon with the highest academic rank in the surgery. Inputs were defined as the number of medical doctors who assisted surgery, and the time of operation from skin incision to closure. An output was defined as the surgical fee. The authors calculated surgeons’ efficiency scores using data envelopment analysis.

The efficiency scores of each surgical specialty were significantly different (p=0.000).

This result demonstrates that the Japanese surgical reimbursement scales still fail to reflect resource utilization despite the revision of surgical fee schedule.