クロックトゲートとクロックレスゲートを用いた単一磁束量子回路の設計と検証

京都大学新制・論文博士博士(情報学)乙第13531号論情博第97号新制||情||137(附属図書館)京都大学大学院情報学研究科通信情報システム専攻(主査)教授 髙木 直史, 教授 佐藤 高史, 教授 橋本 昌宜学位規則第4条第2項該当Doctor of InformaticsKyoto UniversityDFA

Nonequilibrium dissipation-free transport in F1-ATPase and the thermodynamic role of asymmetric allosterism

F1-ATPase (or F1), the highly-efficient and reversible biochemical engine, has motivated physicists as well as biologists to imagine the design principles governing machines in the fluctuating world. Recent experiments have clarified yet another interesting property of F1; the dissipative heat inside the motor is very small, irrespective of the velocity of rotation and energy transport. Conceptual interest is devoted to the fact that the amount of internal dissipation is not simply determined by the sequence of equilibrium pictures, but also relies on the rotational-angular dependence of nucleotide affinity, which is a truly nonequilibrium aspect. We propose that the totally asymmetric allosteric model (TASAM), where adenosine triphosphate (ATP) binding to F1 is assumed to have low dependence on the angle of the rotating shaft, produces results that are most consistent with the experiment. Theoretical analysis proves the crucial role of two time scales in the model, which explains the universal mechanism to produce the internal dissipation-free feature. The model reproduces the characteristic torque dependence of the rotational velocity of F1, and predicts that the internal dissipation upon the ATP synthesis direction rotation becomes large at the low nucleotide condition.Comment: 10 pages, 5 figures + Supplementary Material (9 pages, 9 figures

Why Has the Fraction of Contingent Workers Increased? A case study of Japan

The fraction of contingent workers among all workers in Japan increased from 17% in 1986 to some 34% in 2008. This paper investigates the reason for this secular trend. Both demand and supply increases of contingent workers relative to regular workers are important, as evidenced by the stable relative wage to regular workers. The increase of female labor-force participation explains the supply increase, and the change of industrial composition explains the demand increase. These compositional changes explain about one quarter of the increase of contingent workers. Uncertainty surrounding product demand and the introduction of information and communication technologies increase firms' usage of contingent workers, but its quantitative effect is limited. These findings suggest that the declining importance of firm-specific human capital is a probable cause for the increase of contingent workers.

Why Has the Fraction of Contingent Workers Increased? A Case Study of Japan

This paper explains the secular increase of contingent workers in Japan whose share of employment increased from 17 to 34 percent between 1986 and 2008. Changes in labor-forceand industrial compositions explain about one quarter of the increase of contingent workers. The uncertainty of product demand and the introduction of information and communication technologies increased firms' usage of contingent workers. The increase of contingent workers was concentrated among new entrants to the labor market, male workers of younger cohorts, and female workers of all cohorts, suggesting that the declining importance of the long-term employment relationship is a major cause for the increase of contingent workers.Contingent Workers, Female Labor Supply, Uncertainty, ICT, Japan