Research & Development in the Telecommunication Industry in Prewar Japan -Automatic Telephone Switchboard-

The telephone system was not sufficiently developed in prewar Japan. This study examines the technological development of automatic telephone switchboard (ATS) to clarify the problems of telephone system in prewar Japan. Ministry of Communication(MOC) introduced automatic telephone system in 1923. From the standpoint of the telephone exchange service, it was a very opportune decision; however, it was technologically premature. Although they had conducted research on the system before WW1, their only choice was the primitive S ~ S system. Further, the dependence on import technology caused different A-type and H-type ATS to coexist. Each local telephone exchange district independently introduced a different type. The MOC had to prepare the specifications and parts for repair for two different systems. These factors hampered the improvement of the telecommunication quality. Standardizing the system by using independent technology became the biggest issue for the MOC in the 1930s. In the 1930s, some joint researches were organized with private enterprises. They tried to develop a gT-typeh or gElectronic Tube-typeh ATS. However, the T-type ATS was merely an improvement over the outdated S ~ S system with respect to the circuit design. On the other hand, Matsumae aimed at a novel technology, an electronic common control system. However, a suitable electronic tube was not invented. As a result, the telecommunication industry was unable to resolve the coexistence problem in the prewar period. However, the engineers of MOC and ATS suppliers recognized their technological backwardness and shared an awareness of the importance of standardization by independent technology. This was the starting point for the research and development system of the telecommunication industry in gPostwar Japan.hTelephone system, Automatic Telephone Switchboard, Ministry of Communication, Research & Development, Joint Research

The Evolution of Loan Rate Stickiness Across the Euro Area

To investigate the banking sector integration across euro area countries in terms of loan interest rate stickiness, we estimate structural loan rate curves for 12 euro area countries using time-varying regressions with stochastic volatility. Our results show that the loan rates are sticky to a policy interest rate in all countries for all loan maturities, the degree of stickiness differs across the countries, and the degree of difference is more prominent for longer loan maturities. For short-term loans, the loan rate stickiness decreases and for intermediate- and long-term loans the loan rate stickiness converge to average levels during the sample periods. Banking integration in the euro area is not yet complete, but the degree of heterogeneity in the loan rate stickiness decreases.banking integration, sticky loan interest rate, Bayesian analysis, time-varying regression, Markov chain Monte Carlo

The Effects of Monetary Policy Commitment: Evidence from Time- varying Parameter VAR Analysis

In this paper, we explore the effects of the Bank of Japan's ( BOJ's) policy commitment under zero interest rates on the economy, by considering the transmission channel of altering private-sector expectations. To that end, we carry out a structural vector autoregression analysis on macroeconomic variables and private-sector expectations variables, using a time-varying parameters estimation technique with stochastic volatility. We show empirical evidence on two points. First, the BOJ's policy commitment regarding the future course of short-term interest rates, associated with only a small reduction in policy interest rates, succeeded in altering private-sector expectations. Second, the BOJ's policy commitment alone, nevertheless, was not sufficient to restore the previous trends in prices and output.Policy commitment, policy duration effect, expectations management, Bayesian estimation, time-varying parameter vector autoregression with stochastic volatility

Global Liquidity Trap

In this paper we consider a two-country New Open Economy Macroeconomics model, and analyze the optimal monetary policy when countries cooperate in the face of a "global liquidity trap" -- i.e., a situation where the two countries are simultaneously caught in liquidity traps. The notable features of the optimal policy in the face of a global liquidity trap are history dependence and international dependence. The optimality of history dependent policy is confirmed as in local liquidity trap. A new feature of monetary policy in global liquidity trap is whether or not a country's nominal interest rate is hitting the zero bound affects the target inflation rate of the other country. The direction of the effect depends on whether goods produced in the two countries are Edgeworth complements or substitutes. We also compare several classes of simple interest-rate rules. Our finding is that targeting the price level yields higher welfare than targeting the inflation rate, and that it is desirable to let the policy rate of each country respond not only to its own price level and output gap, but also to those in the other country.Zero Interest Rate Policy, Two-country Model, International Spillover, Monetary Policy Coordination

Symmetry Breaking in Bose-Einstein Condensates

A gaseous Bose-Einstein condensate (BEC) offers an ideal testing ground for studying symmetry breaking, because a trapped BEC system is in a mesoscopic regime, and situations exist under which symmetry breaking may or may not occur. Investigating this problem can explain why mean-field theories have been so successful in elucidating gaseous BEC systems and when many-body effects play a significant role. We substantiate these ideas in four distinct situations: namely, soliton formation in attractive BECs, vortex nucleation in rotating BECs, spontaneous magnetization in spinor BECs, and spin texture formation in dipolar BECs.Comment: Submitted to the proceedings of International Conference on Atomic Physics 200

Surface plasmon resonance tuning of Ag nanoisland films using a CO₂ laser

We demonstrate that the surface plasmon resonance of Ag nanoislands (NIs) can be conveniently tuned through the laser power and irradiation time. For instance, the resonance wavelength of Ag NIs can be tuned from 548 nm to 452 nm under the 3 W laser power simply by varying the irradiation time from 5 s to 2 min. Interestingly, the position-dependent optical absorption spectra and SEM analysis reveals that the Ag NIs gradually disappear from the irradiation center even at 3 W if the irradiation time is longer. This means that the macroscopic diffusion of Ag atoms on the substrate takes place during the CO₂ laser irradiation, and its driving force would be the temperature gradient along the radial direction with respect to the irradiation center due to the spatial beam profile of the laser

Rapid in situ synthesis of polymer-metal nanocomposite films in several seconds using a CO₂ laser

We demonstrate the rapid in situ synthesis of polymer-metal nanocomposite films using a CO₂ laser at 10.6 μm. The mechanism of our method is that the precursor of the metal nanoparticles, i.e., the metallic ions, is very rapidly reduced in the laser-heated polymer matrix without any reducing agent. Unlike other known laser-induced reduction methods using UV lasers, which produce radicals to promote reduction, the CO₂ laser energy is mainly absorbed by the glass substrate, and the laser-heated substrate heats the polymer matrix through heat diffusion to promote reduction. The superiority of the use of CO₂ lasers over nanosecond visible~UV lasers is also demonstrated in terms of the damage to the film. The developed method can be a new alternative to quickly synthesize a variety of polymer-metal nanocomposite films

Size-controlled in situ synthesis of metal–polymer nanocomposite films using a CO₂ laser

In situ synthesis of metal–polymer nanocomposite films by irradiating a CO₂ laser for several seconds is a new alternative to fabricate metal–polymer nanocomposite films. The main features of this method are that the number density of the synthesized metal nanoparticles is very high so that the optical density easily exceeds 0.5 ~ 1.5 for the film thickness of ~ 200 nm, and owing to the short fabrication time and the use of non-focused laser beam, large-scale processing is possible. For this technique to be applicable for a variety of purposes, an important question is how and how much we can control the film properties. In this work, we demonstrate that the size and size distribution of metallic nanoparticles in the synthesized nanocomposite films can be well controlled by the choice of the laser power and irradiation time as well as the concentrations of nanoparticle precursor. Properties of the synthesized films can be roughly understood by considering the diffusion of metallic ions, atoms, and nanoparticles in the polymer film under the elevated temperature induced by the CO₂ laser