光格子中の2軌道量子気体：軌道間スピン交換ダイナミクスとスピン空間量子輸送

京都大学新制・課程博士博士(理学)甲第22983号理博第4660号新制||理||1669(附属図書館)京都大学大学院理学研究科物理学・宇宙物理学専攻(主査)教授 高橋 義朗, 教授 石田 憲二, 教授 川上 則雄学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

Natural Evolution Strategy for Mixed-Integer Black-Box Optimization

This paper proposes a natural evolution strategy (NES) for mixed-integer black-box optimization (MI-BBO) that appears in real-world problems such as hyperparameter optimization of machine learning and materials design. This problem is difficult to optimize because plateaus where the values do not change appear when the integer variables are relaxed to the continuous ones. CMA-ES w. Margin that addresses the plateaus reportedly showed good performance on MI-BBO benchmark problems. However, it has been observed that the search performance of CMA-ES w. Margin deteriorates when continuous variables contribute more to the objective function value than integer ones. In order to address the problem of CMA-ES w. Margin, we propose Distance-weighted eXponential Natural Evolution Strategy taking account of Implicit Constraint and Integer (DX-NES-ICI). We compare the search performance of DX-NES-ICI with that of CMA-ES w. Margin through numerical experiments. As a result, DX-NES-ICI was up to 3.7 times better than CMA-ES w. Margin in terms of a rate of finding the optimal solutions on benchmark problems where continuous variables contribute more to the objective function value than integer ones. DX-NES-ICI also outperformed CMA-ES w. Margin on problems where CMA-ES w. Margin originally showed good performance.Comment: Accepted for GECCO'2

Observation of an Inner-Shell Orbital Clock Transition in Neutral Ytterbium Atoms

内殻電子が励起する時計遷移の初観測に成功 --新奇な光格子時計を用いた超高感度な新物理探索へ--. 京都大学プレスリリース. 2023-04-17.We observe a weakly allowed optical transition of atomic ytterbium from the ground state to the metastable state 4f¹³5d6s² (J=2) for all five bosonic and two fermionic isotopes with resolved Zeeman and hyperfine structures. This inner-shell orbital transition has been proposed as a new frequency standard as well as a quantum sensor for new physics. We find magic wavelengths through the measurement of the scalar and tensor polarizabilities and reveal that the measured trap lifetime in a three-dimensional optical lattice is 1.9(1) s, which is crucial for precision measurements. We also determine the g factor by an interleaved measurement, consistent with our relativistic atomic calculation. This work opens the possibility of an optical lattice clock with improved stability and accuracy as well as novel approaches for physics beyond the standard model

Utilização do Target Costing e de outras técnicas de custeio: um estudo exploratório em municípios de Santa Catarina

This article is the result of a study carried out in preparation for a Masters Dissertation and addresses the theoretical framework of the Target Costing Management System, developed by the Japanese during the 1960s. It is based on an American technique known as Value Engineering, which calculates the cost of a product based on the sale price determined by the market. Its application is particularly important in a competitive business environment. This study aims to collect data and find out, through a descriptive and exploratory research, which costing methods, systems or techniques are used by large and medium-size companies located in Brazilian towns in the State of Santa Catarina, specifically in Itajaí, Navegantes, Ilhota, Gaspar, Blumenau, Brusque, Joinville and Tijucas, in order to identify trends in the use of the "Target Costing" Cost Management System. Data were also collected by means of a questionnaire, applied among cost management teachers in undergraduate Accountancy and Business Administration courses in Higher Education Institutions in Itajaí, Blumenau, Brusque, Joinville and Florianópolis.Este artigo é resultado de estudo efetuado para formulação da Dissertação de Mestrado. Neste trabalho é abordado o referencial teórico sobre o Sistema de Gerenciamento de Custos, denominado "Target Costing", desenvolvido pelos japoneses nos anos sessenta, e que adotou a técnica americana chamada Engenharia de Valor, a qual consiste no cálculo do custo a partir do preço de venda estabelecido pelo mercado. Sua aplicação é especialmente importante num ambiente de competitividade empresarial. A pesquisa objetivou levantar dados e conhecer, através da pesquisa exploratória descritiva, quais métodos, sistemas ou técnicas de custeio são utilizados pelas empresas de médio e grande porte, localizadas em municípios do Estado de Santa Catarina, principalmente nas cidades de Itajaí, Navegantes, Ilhota, Gaspar, Blumenau, Brusque, Joinville e Tijucas, visando identificar propensões à utilização do Sistema de Gerenciamento de Custo "Target Costing". Adicionalmente, buscou-se levantar dados através da aplicação de questionários junto aos professores das disciplinas de custos, nos cursos de graduação em Ciências Contábeis e Administração das Instituições de Ensino Superior nos municípios de Itajaí, Blumenau, Brusque, Joinville e Florianópolis

Observation of spin-exchange dynamics between itinerant and localized ¹⁷¹Yb atoms

We report on the observation of the spin-exchange dynamics of ¹⁷¹Yb atoms in the ground state ¹S₀ and in the metastable state ³P₀. We implement the mixed-dimensional two-orbital system using near-resonant and magic-wavelength optical lattices, where the ¹S₀ and ³P₀ atoms are itinerant in a one-dimensional tube and localized in three dimensions, respectively. By exploiting an optical Stern-Gerlach method, we observe the spin depolarization of the ¹S₀ atoms induced by the spin-exchange interaction with the ³P₀ atom. Our work could pave the way to the quantum simulation of the Kondo effect

Rapid Synthesis of Poly(methyl methacrylate) Particles with High Molecular Weight by Soap‐Free Emulsion Polymerization Using Water‐in‐Oil Slug Flow

flow process for the production of poly(methyl methacrylate) (PMMA) particles is proposed by soap‐free emulsion polymerization using a water‐in‐oil (W/O) slug flow in a microreactor. Thin oil films generated around the dispersed aqueous phase of the W/O slug prevent the prepared particles from adhesion to the microchannel wall, enabling the continuous production of PMMA particles without clogging. The effects of the linear flow rate of the slug flow and the addition of ethanol in the dispersed aqueous phase on the polymerization are evaluated. It is found that increasing the linear flow rate of the slug flow or the addition of ethanol in the dispersed aqueous phase results in PMMA particles with high molecular weight (≈1500 kg mol−1) in 20 min reaction time. It is believed that this process would be a promising way to prepare polymer particles with high molecular weight in a short reaction time

Multimodal Prediction of Cervical Lymph Node Metastasis and Recurrence in Oral Squamous Cell Carcinoma

Background/Aim: Oral squamous cell carcinoma (OSCC) is the most common malignancy in the head/neck region, and cervical lymph node (CLN) metastasis is a strong poor-prognosis factor. In addition, many patients with OSCC experience recurrence despite multidisciplinary treatment. We sought to identify factors associated with CLN metastasis and recurrence in patients with OSCC. Patients and Methods: We evaluated a total of 45 patients and 233 target CLNs. The longest diameter of the target CLN, the shortest diameter of the target CLN (LS), the area of the target CLN, and the relative computed tomography (CT) values of the target CLNs calculated based on the CT values of the internal jugular vein (LCT) were obtained from preoperative CT images, and the maximum standardized uptake values of the primary tumor (pSUV) and target CLN (nSUV) were obtained from preoperative 18F-fluorodeoxyglucose-positron emission tomography/CT images. We performed immunohistochemical staining for cytokeratin 13 (CK13) and 17 (CK17) on neck dissection tissues. Results: A discrimination equation was used that can predict CLN metastasis with a 92.2% discrimination rate using LS, LCT, pSUV, and nSUV. The CLNs were divided into discrimination and non-discrimination groups based on discriminant equations and CK13 and CK17 were used as the objective variables. A significantly higher recurrence rate was observed in the non-discrimination group (CK13: 5-year recurrence rate 28.6% vs. 64.3%, p<0.01; CK17: 5-year recurrence rate 28.0% vs. 76.0%, p<0.01). Conclusion: CLN metastases in OSCC can be assessed by combining preoperative imaging. The combined use of CK13 and CK17 expression with imaging findings offers an integrated approach to predict OSCC recurrence

The effect of staged projekt management on product innovation: Evidence from a firm survey

This study examines whether staged project management is beneficial or harmful for making product innovations. Using a unique firm survey for Japan, we find that firms that employed staged project management had a higher likelihood of introducing new products to the market. Additional estimations show that the positive effect of staged project management on product innovation is stronger when firms provided feedback at the interim stages. In contrast, whether and how firms set milestones was not associated with the likelihood of product innovation. The marginal effect of feedback was larger for new-to-market product innovation than for new-to-firm product innovation, and the feedback from non-R&D organizations within the firm in the initial stages was particularly beneficial for the introduction of new-to-market products. Our findings suggest that staged project management is beneficial for product innovation, but its effectiveness depends on how firms set milestones and feedback as well as the nature of innovation

Observation of spin-space quantum transport induced by an atomic quantum point contact

冷却原子の量子状態を制御し新たな「流れ」を実現 --「原子回路」で電子の流れをシミュレーションする--. 京都大学プレスリリース. 2021-11-22.Quantum transport is ubiquitous in physics. So far, quantum transport between terminals has been extensively studied in solid state systems from the fundamental point of views such as the quantized conductance to the applications to quantum devices. Recent works have demonstrated a cold-atom analog of a mesoscopic conductor by engineering a narrow conducting channel with optical potentials, which opens the door for a wealth of research of atomtronics emulating mesoscopic electronic devices and beyond. Here we realize an alternative scheme of the quantum transport experiment with ytterbium atoms in a two-orbital optical lattice system. Our system consists of a multi-component Fermi gas and a localized impurity, where the current can be created in the spin space by introducing the spin-dependent interaction with the impurity. We demonstrate a rich variety of localized-impurity-induced quantum transports, which paves the way for atomtronics exploiting spin degrees of freedom