Optimal Macroprudential Policy for Korean Economy

Yuki Teranishi,Ko Munakata,Junichi Fujimoto 서울대학교 경제연구소 2015 Seoul journal of economics Vol.28 No.2

Fujimoto et al. (2014) set up a model with financial frictions through search and matching between firms and banks in the loan market. They also show that optimal policy criteria in the model include terms of credit variables. In this paper, we calibrate the model of Fujimoto et al. (2014) for South Korea and investigate the simple and optimal monetary and macroprudential policy rules that include credit variables in addition to the consumption gap and inflation rate as explanatory variables. We compare the performances of a standard Taylor rule and these optimal rules. Numerical simulations show that the simple macroprudential and monetary policy rules with credit terms can induce higher welfare than the estimated Taylor rule for the Korean economy. Simultaneously, simple macroprudential and monetary policy rules with credit terms do not always improve welfare.

Autonomous calibration method of the reference flat surface of an interferometer without using a standard flat surface

Fujimoto, Ikumatsu,Takatsuji, Toshiyuki,Nishimura, Kunitoshi,Kim, Min Young The Optical Society 2012 Applied optics Vol.51 No.20

Policy Implications for Cities in Music Industry of Japan

Fujimoto Noritsugu 대한지리학회 2011 대한지리학회 컨퍼런스 자료집 Vol.- No.6

6d Dirac fermion on a rectangle; scrutinizing boundary conditions, mode functions and spectrum

Fujimoto, Y.,Hasegawa, K.,Nishiwaki, K.,Sakamoto, M.,Tatsumi, K. North Holland 2017 Nuclear physics, B Vol.922 No.-

We classify possible boundary conditions of a 6d Dirac fermion Ψ on a rectangle under the requirement that the 4d Lorentz structure is maintained, and derive the profiles and spectrum of the zero modes and nonzero KK modes under the two specific boundary conditions, (i) 4d-chirality positive components being zero at the boundaries and (ii) internal chirality positive components being zero at the boundaries. In the case of (i), twofold degenerated chiral zero modes appear which are localized towards specific directions of the rectangle pointed by an angle parameter θ. This leads to an implication for a new direction of pursuing the origin of three generations in the matter fields of the standard model, even though triple-degenerated zero modes are not realized in the six dimensions. When such 6d fermions couple with a 6d scalar with a vacuum expectation value, θ contributes to a mass matrix of zero-mode fermions consisting of Yukawa interactions. The emergence of the angle parameter θ originates from a rotational symmetry in the degenerated chiral zero modes on the rectangle extra dimensions since they do not feel the boundaries. In the case of (ii), this rotational symmetry is promoted to the two-dimensional conformal symmetry though no chiral massless zero mode appears. We also discuss the correspondence between our model on a rectangle and orbifold models in some details.

Structure and Formation of Diesel Fuel Spray

Fujimoto, Hajime,Dan, Tomohisa The Institute for Liquid Atomization and Spray Sys 1996 한국액체미립화학회지 Vol.1 No.4

Research and development studies in internal combustion engines are set on a turning point due to requirements mostly purify the polluted environments. Naturally, basic studies concerned about engines are objected to elucidate formation mechanism of harmful matters, such as nitric oxide $(NO_x)$ and particulate matters. And for diesel engines, phenomenon in combustion chambers are analyzed in several approach ways in order to obtain detail understandings in closed and hardly observing space. In this article. it is discussed that the formation mechanism of diesel fuel sprays, mostly non-evaporating free diesel sprays. From that it would be promoted some new innovations in internal combustion engines of next generation.

Present Status and Perspectives of Cancer Chemotherapy to discover more potential antitumor agents

Fujimoto, Shuichi 한국균학회 1987 韓國菌學會誌 Vol.15 No.3

In order to discover potential new antitumor agents, we should understand the backgrounds for refractoriness of a majority of human tumors towards chemotherapy. Three kinds of mechanisms for resistance, i. e., temporary, kinetic and inherent resistances, are introduced in the present paper. Antitumor agents are classified into two groups with respect to modes for cytocidal action against tumor cells in vitro and in vivo. One is a cell-cycle-phase specific and the other is a cell-cycle-phase nonspecific(however, cycle specific). The former drugs show their cytocidal activity against tumor cells in a specific phase of the cell cycle. Antimetabolites and vinca alkaloids belong to this class. Thess drugs show logarithmic cytocidal action with increasing dose. After eradication of tumor cells in this specific phase, however, the remaining tumor cells in other phases are insensitive to these drugs, leading to the temporary resistance. Rapidiy growing tumors have a relatively high sensitivity to antitumor agents. Clinically detectable tumor size is approximately 1 ㎝ or more in diameter, and this tumor mass contains approximately 1 × 10^9 cells(1g) and tumor cells already carried out 30 times cell division. On the other hand, tumor mass at terminal stage reaches 1 × 10^(12) cells(1 ㎏) or more, and they carry out further 10 times cell division. The tumor growth rate we refer is those between the tumor mass of lg and 1 ㎏. Majority of human solid tumors have slow growth rate, leading to the kinetic resistance. Appearance of drug-resistant tumor cells is a serious obstacle to perform an effective chemotherapy, leading to the inherent resistance. It has been observed for a number of different tumor cells in culture that approximately 1 in 10^6(10^(-6)) cells of a given population is resistant to a given drug. Furthermore, most antitumor agents are variably mutagenic so that, during treatment, mutant daughter cells are produced that have a higher potential for being genetically drug-resistant. Several studies indicate that such chemical mutagens will increase the population of drug-resistant cells by a factor of 100. Therefore, treatment failure due to drug resistance may occur if the initial unexposed population of tumor cells is greater than 108 or if the number of daughter cells produced during treatment is greater than 10⁴. The clinical studies of new antitumor agents are carried out for those patients with tumors refractory to chemotherapy either initially or after treatment. Those tumor cells may show the pleiotropic cross resistance to new antitumor agents. Taking these problems into consideration, a new device should be developed for discovering new antitumor agents from natural products as well as from synthetic compounds.

Comprehensive analysis of Yukawa hierarchies onT2/ZNwith magnetic fluxes

Fujimoto, Yukihiro,Kobayashi, Tatsuo,Nishiwaki, Kenji,Sakamoto, Makoto,Tatsuta, Yoshiyuki American Physical Society 2016 Physical Review D Vol.94 No.3

<P>Based on the results of the classification by T.-h. Abe et al., Nucl. Phys. B894, 374 (2015)., we exhaustively investigate Yukawa sector of U(8) model on magnetized orbifolds T-2 / Z(2), T-2 / Z(3), T-2 / Z(4) and T-2 / Z(6) by evaluating ratios of the mass eigenvalues of the three states in all the possible configurations with one and two Higgs pairs where three generations are realized in fermions. Because of the smearing effect via kinetic mixing, one can realize a hierarchy such as 10(-2)-10(-3), but it is very difficult to achieve the mass ratio between the up and top quarks (m(up) / m(top) similar to 10(-5)) on the complicated magnetized orbifolds T-2 / Z(N) (N similar to 3,4,6).</P>

Extended supersymmetry in Dirac action with extra dimensions

Fujimoto, Yukihiro,Hasegawa, Kouhei,Nishiwaki, Kenji,Sakamoto, Makoto,Tatsumi, Kentaro,Ueba, Inori IOP 2018 JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL Vol.51 No.43

<P>We investigate a new realization of extended quantum-mechanical supersymmetry. We first show that an <img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn001.gif'/> quantum-mechanical supersymmetry is hidden in the four-dimensional (4D) spectrum of the Kaluza–Klein decomposition for the higher dimensional Dirac field, that is, Kaluza–Klein mode functions of 4D right-handed spinors and 4D left-handed ones form <img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn002.gif'/> supermultiplets. In addition to <img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn003.gif'/> supersymmetry, we discover that an <img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn004.gif'/>-extended supersymmetry (<img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn005.gif'/> for <I>d</I>  =  even (odd) extra dimensions) is further hidden in the 4D spectrum. The extended symmetry can explain additional degeneracy of the spectrum. Furthermore, we show that a superpotential can be introduced into the <img ALIGN='MIDDLE' ALT='' SRC='http://ej.iop.org/images/1751-8121/51/43/435201/aaadea2ieqn006.gif'/>-extended supercharges and clarify the condition to preserve the supersymmetry. The partial breaking of the supersymmetry is also demonstrated.</P>

Dynamical generation of fermion mass hierarchy in an extra dimension

Fujimoto, Yukihiro,Miura, Takashi,Nishiwaki, Kenji,Sakamoto, Makoto American Physical Society 2018 Physical Review D Vol.97 No.11

<P>We propose a new mechanism to produce a fermion mass hierarchy dynamically in a model with a single generation of fermions. A five-dimensional gauge theory on an interval with point interactions (zero-width brans) takes responsibility for realizing three generations and each massless zero mode localizes at boundaries of the segments on the extra dimension. An extra dimension coordinate-dependent vacuum expectation value of a scalar field makes large differences in overlap integrals of the localized zero modes and then an exponential fermion mass hierarchy can appear. The positions of the point interactions control the magnitude of the fermion mass hierarchy and are determined by the minimization condition of the Casimir energy. As a result of the minimization of the Casimir energy, an exponential mass hierarchy appears dynamically. We also discuss the stability of the extra dimension.</P>

High-throughput Preparation and Characterization of Powder and Thin-film Library for Electrode Materials

Fujimoto Kenjiro,Onoda Kazuhiro,Ito Shigeru 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

Powder library of pseudo four components Li-Ni-Co-Ti compounds were prepared for exploring the composition region with the single phase of the layer-type structure by using combinatorial high-throuput preparation system "M-ist Combi" based on electrostatic spray deposition method. The new layer-type compounds were found wider composition region than the previous report. This process is promising way to find multi component functional materials.