556 research outputs found
<研究ノート> 海外派遣者の増減および海外子会社のパフォーマンス
Previous studies on the effect of subsidiary staffing on subsidiary performance have examined the relationship between the two variables at certain points in time. These studies demonstrate that subsidiaries with more (or fewer) parent country nationals (PCNs) tend to demonstrate higher performance. However, these studies do not fully analyze whether the performance of a focal subsidiary improves by increasing (or decreasing) the number of PCNs assigned to the subsidiary. To answer this research question, this study addresses the way in which changes in a focal subsidiary’s staffing affect the subsidiary’s performance. It analyzes a panel dataset consisting of 11,286 observations of foreign subsidiaries owned by multinational corporations. This study demonstrates that a change in the deployment of PCNs has a U-shaped relationship with subsidiary performance, and the curve indicates that the performance of a focal subsidiary improves by both increasing and decreasing the deployment of PCNs. This study also finds that the slope of the U-shaped curve is flatter in institutionally distant host countries than in institutionally similar countries. This finding indicates that institutional differences between the host and home countries diminish the positive effect of increasing and decreasing the deployment of PCNs
The Dominant Practice for Foreign Subsidiary Staffing and the Subsidiary Performance
This study examines whether isomorphic behavior by multinational corporations positively or negatively affect the performance of foreign subsidiaries. Although previous studies find that multinational corporations have a tendency to mimic practices adopted by other firms, the financial consequences of mimetic behavior remains uncovered. This study addresses multinational corporations\u27 isomorphic behavior regarding foreign subsidiary staffing and hypothesizes the relationship between the imitation of the dominant practice for subsidiary staffing and the subsidiary performance. The panel dataset consisting of 3,284 foreign subsidiaries of multinational corporations are used to test the hypotheses. The results obtained from a fixed effect model indicate that the imitation of the dominant practice adopted in the host country negatively affects the subsidiary performance. This study also finds that the negative relationship between mimetic behavior and subsidiary performance becomes greater as the institutional distance between the host country and the home country increases. The results of this study suggest that isomorphic behavior in pursuit of legitimacy is accompanied by the loss of efficiency
State Concentration Exponent as a Measure of Quickness in Kauffman-type Networks
We study the dynamics of randomly connected networks composed of binary
Boolean elements and those composed of binary majority vote elements. We
elucidate their differences in both sparsely and densely connected cases. The
quickness of large network dynamics is usually quantified by the length of
transient paths, an analytically intractable measure. For discrete-time
dynamics of networks of binary elements, we address this dilemma with an
alternative unified framework by using a concept termed state concentration,
defined as the exponent of the average number of t-step ancestors in state
transition graphs. The state transition graph is defined by nodes corresponding
to network states and directed links corresponding to transitions. Using this
exponent, we interrogate the dynamics of random Boolean and majority vote
networks. We find that extremely sparse Boolean networks and majority vote
networks with arbitrary density achieve quickness, owing in part to long-tailed
in-degree distributions. As a corollary, only relatively dense majority vote
networks can achieve both quickness and robustness.Comment: 6 figure
Cross Correlation of the Extragalactic Gamma-ray Background with Thermal Sunyaev-Zel'dovich Effect in the Cosmic Microwave Background
Cosmic rays in galaxy clusters are unique probes of energetic processes
operating with large-scale structures in the Universe. Precise measurements of
cosmic rays in galaxy clusters are essential for improving our understanding of
non-thermal components in the intracluster-medium (ICM) as well as the accuracy
of cluster mass estimates in cosmological analyses. In this paper, we perform a
cross-correlation analysis with the extragalactic gamma-ray background and the
thermal Sunyaev-Zel'dovich (tSZ) effect in the cosmic microwave background. The
expected cross-correlation signal would contain rich information about the
cosmic-ray-induced gamma-ray emission in the most massive galaxy clusters at
. We analyze the gamma-ray background map with 8 years of data
taken by the Large Area Telescope onboard Fermi satellite and the publicly
available tSZ map by Planck. We confirm that the measured cross-correlation is
consistent with a null detection, and thus it enables us to put the tightest
constraint on the acceleration efficiency of cosmic ray protons at shocks in
and around galaxy clusters. We find the acceleration efficiency must be below
5\% with a confidence level when the hydrostatic mass bias of
clusters is assumed to be 30\%, and our result is not significantly affected by
the assumed value of the hydrostatic mass bias. Our constraint implies that the
non-thermal cosmic-ray pressure in the ICM can introduce only a level
of the hydrostatic mass bias, highlighting that cosmic rays alone do not
account for the mass bias inferred by the Planck analyses. Finally, we discuss
future detectability prospects of cosmic-ray-induced gamma rays from the
Perseus cluster for the Cherenkov Telescope Array.Comment: 19 pages, 15 figures, 1 table. Accepted for publication in Phys. Rev.
Isolation and gene analysis of interferon α-resistant cell clones of the hepatitis C virus subgenome
AbstractHepatitis C virus (HCV) proteins appear to play an important role in IFN-resistance, but the molecular mechanism remains unclear. To clarify the mechanism in HCV replicon RNA harboring Huh-7 cells (Huh-9-13), we isolated cellular clones with impaired IFNα-sensitivity. Huh-9-13 was cultured for approximately 2 months in the presence of IFNα, and 4 IFNα-resistant cell clones showing significant resistances were obtained. When total RNA from clones was introduced into Huh-7 cells, the transfected cells also exhibited IFNα-resistance. Although no common mutations were present, mutations in NS3 and NS5A regions were accumulated. Transactivation of IFNα and IFNα-stimulated Stat-1 phosphorylation were reduced, and the elimination of HCV replicon RNA from the clones restored the IFNα signaling. These results suggest that the mutations in the HCV replicon RNA, at least in part, cause an inhibition of IFN signaling and are important for acquisition of IFNα resistance in Huh-9-13
Pre-DECIGO can get the smoking gun to decide the astrophysical or cosmological origin of GW150914-like binary black holes
Pre-DECIGO consists of three spacecraft arranged in an equilateral triangle
with 100km arm lengths orbiting 2000km above the surface of the earth. It is
hoped that the launch date will be in the late 2020s.
Pre-DECIGO has one clear target: binary black holes (BBHs) like GW150914 and
GW151226. Pre-DECIGO can detect BBH mergers up to
redshift . The cumulative event rate is in the Pop III origin model of BBHs like GW150914, and it
saturates at , while in the primordial BBH (PBBH) model, the
cumulative event rate is at
even if only of the dark matter consists of PBHs, and it is
still increasing at . In the Pop I/II model of BBHs, the cumulative event
rate is and it saturates at . We present the requirements on orbit accuracy, drag free techniques, laser
power, frequency stability, and interferometer test mass. For BBHs like
GW150914 at 1Gpc, SNR is achieved with the definition of Pre-DECIGO in
the Hz band. Pre-DECIGO can measure the mass spectrum and the
-dependence of the merger rate to distinguish various models of BBHs like
GW150914.
Pre-DECIGO can also predict the direction of BBHs at with an accuracy
of and a merging time accuracy of s at about a
day before the merger so that ground-based GW detectors further developed at
that time as well as electromagnetic follow-up observations can prepare for the
detection of merger in advance. For intermediate mass BBHs at a large redshift
, the QNM frequency after the merger can be within the Pre-DECIGO band
so that the ringing tail can also be detectable to confirm the Einstein theory
of general relativity with SNR.
[abridged]Comment: 17 pages, 10 figures, added some references, modifications to match
the published version in PTE
Non-learning Stereo-aided Depth Completion under Mis-projection via Selective Stereo Matching
We propose a non-learning depth completion method for a sparse depth map
captured using a light detection and ranging (LiDAR) sensor guided by a pair of
stereo images. Generally, conventional stereo-aided depth completion methods
have two limiations. (i) They assume the given sparse depth map is accurately
aligned to the input image, whereas the alignment is difficult to achieve in
practice. (ii) They have limited accuracy in the long range because the depth
is estimated by pixel disparity. To solve the abovementioned limitations, we
propose selective stereo matching (SSM) that searches the most appropriate
depth value for each image pixel from its neighborly projected LiDAR points
based on an energy minimization framework. This depth selection approach can
handle any type of mis-projection. Moreover, SSM has an advantage in terms of
long-range depth accuracy because it directly uses the LiDAR measurement rather
than the depth acquired from the stereo. SSM is a discrete process; thus, we
apply variational smoothing with binary anisotropic diffusion tensor (B-ADT) to
generate a continuous depth map while preserving depth discontinuity across
object boundaries. Experimentally, compared with the previous state-of-the-art
stereo-aided depth completion, the proposed method reduced the mean absolute
error (MAE) of the depth estimation to 0.65 times and demonstrated
approximately twice more accurate estimation in the long range. Moreover, under
various LiDAR-camera calibration errors, the proposed method reduced the depth
estimation MAE to 0.34-0.93 times from previous depth completion methods.Comment: 15 pages, 13 figure
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