685 research outputs found
Effects of the distant population density on spatial patterns of demographic dynamics
Spatiotemporal patterns of population changes within and across countries
have various implications. Different geographical, demographic and
econo-societal factors seem to contribute to migratory decisions made by
individual inhabitants. Focussing on internal (i.e., domestic) migration, we
ask whether individuals may take into account the information on the population
density in distant locations to make migratory decisions. We analyse population
census data in Japan recorded with a high spatial resolution (i.e., cells of
size 500 m 500 m) for the entirety of the country and simulate
demographic dynamics induced by the gravity model and its variants. We show
that, in the census data, the population growth rate in a cell is positively
correlated with the population density in nearby cells up to a radius of 20 km
as well as that of the focal cell. The ordinary gravity model does not capture
this empirical observation. We then show that the empirical observation is
better accounted for by extensions of the gravity model such that individuals
are assumed to perceive the attractiveness, approximated by the population
density, of the source or destination cell of migration as the spatial average
over a radius of km.Comment: 22 figures, 2 tables, fixed an incorrect publication yea
Win-stay lose-shift strategy in formation changes in football
Managerial decision making is likely to be a dominant determinant of
performance of teams in team sports. Here we use Japanese and German football
data to investigate correlates between temporal patterns of formation changes
across matches and match results. We found that individual teams and managers
both showed win-stay lose-shift behavior, a type of reinforcement learning. In
other words, they tended to stick to the current formation after a win and
switch to a different formation after a loss. In addition, formation changes
did not statistically improve the results of succeeding matches.The results
indicate that a swift implementation of a new formation in the win-stay
lose-shift manner may not be a successful managerial rule of thumb.Comment: 7 figures, 11 table
Phase Transition in Potts Model with Invisible States
We study phase transition in the ferromagnetic Potts model with invisible
states that are added as redundant states by mean-field calculation and Monte
Carlo simulation. Invisible states affect the entropy and the free energy,
although they do not contribute to the internal energy. The internal energy and
the number of degenerated ground states do not change, if invisible states are
introduced into the standard Potts model. A second-order phase transition takes
place at finite temperature in the standard -state ferromagnetic Potts model
on two-dimensional lattice for , and 4. However, our present model on
two-dimensional lattice undergoes a first-order phase transition with
spontaneous -fold symmetry breaking (, and 4) due to entropy effect
of invisible states. We believe that our present model is a fundamental model
for analysis of a first-order phase transition with spontaneous discrete
symmetry breaking.Comment: 8 pages, 4 figure
Population changes in residential clusters in Japan
Population dynamics in urban and rural areas are different. Understanding
factors that contribute to local population changes has various socioeconomic
and political implications. In the present study, we use population census data
in Japan to examine contributors to the population growth of residential
clusters between years 2005 and 2010. The data set covers the entirety of Japan
and has a high spatial resolution of 500500, enabling us
to examine population dynamics in various parts of the country (urban and
rural) using statistical analysis. We found that, in addition to the area,
population density, and age, the shape of the cluster and the spatial
distribution of inhabitants within the cluster are significantly related to the
population growth rate of a residential cluster. Specifically, the population
tends to grow if the cluster is "round" shaped (given the area) and the
population is concentrate near the center rather than periphery of the cluster.Comment: 3 figures, 4 table
Double- Order in a Frustrated Random Spin System
We use the three-dimensional Heisenberg model with site randomness as an
effective model of the compound Sr(FeMn)O. The model consists
of two types of ions that correspond to Fe and Mn ions. The nearest-neighbor
interactions in the ab-plane are antiferromagnetic. The nearest-neighbor
interactions along the c-axis between Fe ions are assumed to be
antiferromagnetic, whereas other interactions are assumed to be ferromagnetic.
From Monte Carlo simulations, we confirm the existence of the
double- ordered phase characterized by two wave numbers,
and . We also identify the spin ordering pattern in
the double- ordered phase.Comment: 5pages, 3figure
Tracer-encapsulated solid pellet injection system
he method of tracer-encapsulated solid pellet (TESPEL) is now flourishing in various fields. The original purpose to study impurity transport without giving substantial perturbation on the plasma is implemented successfully for years. In addition to this, TESPEL is being intensively applied to study thermal (especially non-local) transport, high energy particles with the use of TESPEL ablation cloud, and spectroscopy from the viewpoint of atomic data. It is now further growing up to the utilization of multiple tracer methods which was not planned at the initial phase of the project. The proof-of-principle experiment using triple tracers has been successfully implemented. This opens a way to compare the Z dependence or mass dependence of impurity transport. In this article, as TESPEL is used in a variety of fields, the TESPEL injection system is summarized together with the method of TESPEL production, TESPEL storage disk, TESPEL guide system, and the differential pumping system. Also, the observation system for TESPEL flight and TESPEL ablation is explained
コキャク コミュニケーション ニ オケル ジュヨウ ノ サイ ソシキカ
本稿では、セールスパーソンが営業実践によってその都度顧客を立ち上げ、個々の顧客の需要を立ち上げることによって販売を達成していることを指摘し、かつ「営業には高度で特殊な能力は必要ではない」ことを主張する。まず第1節では、スカンジナビア航空のカールソンとノードストローム百貨店のサンダースによる「顧客コミュニケーション」の考え方が示される。第2節では、ノードストローム百貨店に来店した2人の女性客がドレスを求める事例をもとに、顧客・需要概念が再検討される。第3節では、筆者自身によるフィールドワークの事例から、某外資系生命保険営業における「顧客コミュニケーション」の場面の実際が明らかにされる。第4節では、認知科学における状況論的アプローチに依拠しつつ認知的道具をめぐって、前節の事例が分析される。そして第5節では、本稿の結論とセールスマネジメントに対するインプリケーションが提示されることにな
Personal customizing exercise with a wearable measurement and control unit
BACKGROUND: Recently, wearable technology has been used in various health-related fields to develop advanced monitoring solutions. However, the monitoring function alone cannot meet all the requirements of customizing machine-based exercise on an individual basis by relying on biosignal-based controls. We propose a new wearable unit design equipped with measurement and control functions to support the customization process. METHODS: The wearable unit can measure the heart rate and electromyogram signals during exercise performance and output workload control commands to the exercise machines. The workload is continuously tracked with exercise programs set according to personally customized workload patterns and estimation results from the measured biosignals by a fuzzy control method. Exercise programs are adapted by relying on a computer workstation, which communicates with the wearable unit via wireless connections. A prototype of the wearable unit was tested together with an Internet-based cycle ergometer system to demonstrate that it is possible to customize exercise on an individual basis. RESULTS: We tested the wearable unit in nine people to assess its suitability to control cycle ergometer exercise. The results confirmed that the unit could successfully control the ergometer workload and continuously support gradual changes in physical activities. CONCLUSION: The design of wearable units equipped with measurement and control functions is an important step towards establishing a convenient and continuously supported wellness environment
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