This numerical study reports the change in natural-convection heat transfer characteristics from a stationary 2D horizontal cylinder with the change in the aspect ratio (ratio of cylinder radius to ...enclosure length,
R
/
L
) of a cooled square outer enclosure and position of the cylinder for Rayleigh number
(
R
a
D
)
of
1.114
×
10
4
and
1.114
×
10
5
. The cylinder position is varied between concentric to eccentric positions along the horizontal and vertical median and diagonal of the enclosure for
R
/
L
in the range from
0.1
to
0.225
. The simulations are performed under non-Boussinesq conditions and Immersed Boundary Method to model the cylinder surface. The combination of thermal stratification effects, optimized convection flow and the effect of heat conduction between cylinder periphery and the enclosure wall is found to determine the net heat transfer behavior. For eccentricity along the vertical median of the enclosure, the position near the bottom wall and the position near the top wall results in heat transfer enhancement at the lower
R
/
L
values and higher
R
/
L
values respectively. The concentric position of the cylinder results in maximum heat transfer at
R
/
L
=
0.15
for
Ra
D
=
1.114
×
10
4
and at
R
/
L
=
0.175
for
Ra
D
=
1.114
×
10
5
. For eccentricity along the diagonal, the position near the top wall results in maximum heat transfer enhancement at
R
/
L
=
0.175
and higher for
Ra
D
=
1.114
×
10
4
and at
R
/
L
=
0.2
and higher for
Ra
D
=
1.114
×
10
5
. The intensity of the chimney effect depending on the Rayleigh number is found to be the driving parameter at lower
R
/
L
values which determines the optimum cylinder position along the horizontal median. The effect of heat conduction with the vertical wall results in heat transfer enhancement for the position nearest to the vertical wall at
R
/
L
values higher than
0.175
.
Various reports have shown that internal and external exposure levels of local residents after the accident at Fukushima Daiichi nuclear power plant were very low. However, there are serious ...postdisaster health effects in the form of increased prevalence of diabetes and other chronic conditions. Stress, changes in the social environment and in living arrangements, and disruption in healthcare support provided by a network of people have resulted in increasing the cost of care and changing patients’ behaviour, such as delay in visiting a hospital. In addition to radiation protection, it is necessary, when looking after the health of Fukushima residents, to focus on human networking, social infrastructure, and protection of culture and history that are intangible, and not to overlook their roles in health.
The problem of uneven distribution of medical services and inequitable distribution of physicians is drawing much attention worldwide. Revealing how changes in the specialty training system in Japan ...have affected the distribution of doctors could help us understand this problem. In 2018, a new and standardized specialty training system was implemented by the Japanese Medical Specialty Board, which is recognized by the Ministry of Health, Labor and Welfare. The purpose of this study was to investigate how this new system has affected the geographical distribution of doctors commencing specialty training (trainees) and choice of specialty in Japan.
Retrospective observational study.
The change in the number of trainees between the control period (2012–2014) and 2018 was investigated, taking into account the prefecture and specialty selected. Population, the proportion of residents aged 65 years or older (aging rate), and the total number of overall doctors in each prefecture were considered as the background characteristics of each prefecture. We created a Lorenz curve and calculated the Gini coefficient for the distribution of trainees.
In 2018, the number of trainees per 100,000 population increased to 6.6 nationwide compared with 5.5 during the control period. The number of trainees per 100,000 population in 2018 increased in prefectures with a large population of ≧ 2,000,000, a low aging rate (<27%), and a high doctor density (≧ 250 doctors per 100,000 population). The Gini coefficient showed an increase to 0.226 in 2018 compared with only 0.160 during the control period.
After the implementation of the new training system, there was an increase in the number of doctors enrolling in specialty programs, and the specialties other than internal medicine and surgery have attracted more trainees. Inequality in the distribution of doctors between urban and rural prefectures worsened. This indicates the need to explore new ways of balancing distribution while maintaining optimal opportunities for specialist training.
•In 2018, the Japanese Medical Specialty Board implemented a new and standardized physician specialty training system in Japan.•We investigated the change in the number of trainees between the control period (2012–2014) and 2018.•The total number of trainees and that per 100,000 population showed an increase in all specialties.•The Gini coefficient showed an increase to 0.226 in 2018 compared with only 0.160 during the control period.•Seeking ways of balancing trainees's unevenness while maintaining optimal opportunities for specialist training is needed.
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