種類学術雑誌論文 部局
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作成者 : 内田 康 出版者 : 村上春樹とアダプテーション研究会 発行日 : 2023-01-31
作成者 : 山根 由美恵 出版者 : 村上春樹とアダプテーション研究会 発行日 : 2023-01-31
創刊の辞
村上春樹とアダプテーション研究 1 巻
作成者 : 山根 由美恵 出版者 : 村上春樹とアダプテーション研究会 発行日 : 2023-01-31
We investigate symmetric equilibria of mutual reinforcement learning when both players alternately learn the optimal memory-two strategies against the oppo-nent in the repeated prisoners' dilemma game. We provide a necessary condi-tion for memory-two deterministic strategies to form symmetric equilibria. We then provide three examples of memory-two deterministic strategies which form symmetric mutual reinforcement learning equilibria. We also prove that mu-tual reinforcement learning equilibria formed by memory-two strategies are also mutual reinforcement learning equilibria when both players use reinforcement learning of memory-n strategies with n > 2.
作成者 : 上田 仁彦 出版者 : Elsevier 発行日 : 2023-03-01
作成者 : Hintereder-Emde Franz 出版者 : 山口大学人文学部異文化交流研究施設 発行日 : 2022-08-01
作成者 : 柏木 寧子 | 吉田 真樹 | 上原 雅文 発行日 : 2022-09
Zero-determinant strategies are memory-one strategies in repeated games which unilaterally enforce linear relations between expected payoffs of players. Recently, the concept of zero-determinant strategies was extended to the class of memory-n strategies with n _ 1, which enables more compli-cated control of payoffs by one player. However, what we can do by memory-n zero-determinant strategies is still not clear. Here, we show that memory-n zero-determinant strategies in repeated games can be used to control condi-tional expectations of payoffs. Equivalently, they can be used to control ex-pected payoffs in biased ensembles, where a history of action pro_les with large value of bias function is more weighted. Controlling conditional expectations of payoffs is useful for strengthening zero-determinant strategies, because play-ers can choose conditions in such a way that only unfavorable action pro_les to one player are contained in the conditions. We provide several examples of memory-n zero-determinant strategies in the repeated prisoner's dilemma game. We also explain that a deformed version of zero-determinant strategies is easily extended to the memory-n case.
作成者 : 上田 仁彦 出版者 : Springer Nature 発行日 : 2022-09-05
Zero-determinant strategies are a class of memory-one strategies in repeated games which unilaterally enforce linear relationships between payoffs. It has long been unclear for what stage games zero-determinant strategies exist. We provide a necessary and sufficient condition for the existence of zero-determinant strategies. This condition can be interpreted as the existence of two different actions which unilaterally adjust the total value of a linear combination of payoffs. A relation between the class of stage games where zero-determinant strategies exist and other class of stage games is also provided.
作成者 : 上田 仁彦 出版者 : Physical Society of Japan 発行日 : 2022-07-11
The quadratic unconstrained binary optimization (QUBO) problem is categorized as an NP-hard combinatorial optimization problem. The variable neighborhood search (VNS) algorithm is one of the leading algorithms used to solve QUBO problems. As neighborhood structure change is the central concept in the VNS algorithm, the design of the neighborhood structure is crucial. This paper presents a modified VNS algorithm called "B-VNS", which can be used to solve QUBO problems. A binomial trial was used to construct the neighborhood structure, and this was used with the aim of reducing computation time. The B-VNS and VNS algorithms were tested on standard QUBO problems from Glover and Beasley, on standard max-cut problems from Helmberg-Rendl, and on those proposed by Burer, Monteiro, and Zhang. Finally, Mann-Whitney tests were conducted using α = 0.05, to statistically compare the performance of the two algorithms. It was shown that the B-VNS and VNS algorithms are able to provide good solutions, but the B-VNS algorithm runs substantially faster. Furthermore, the B-VNS algorithm performed the best in all of the max-cut problems, regardless of problem size, and it performed the best in QUBO problems, with sizes less than 500. The results suggest that the use of binomial distribution, to construct the neighborhood structure, has the potential for further development.
作成者 : Pambudi Dhidhi | 川村 正樹 出版者 : Multidisciplinary Digital Publishing Institute 発行日 : 2022-06-02
Wireless power transfer (WPT) systems have attracted considerable attention in relation to providing a reliable and convenient power supply. Among the challenges in this area are maintaining the performance of the WPT system with the presence of a human body and minimizing the induced physical quantities in the human body. This study proposes a magnetic resonant coupling WPT (MRC-WPT) system that utilizes a resonator with a grounded loop to mitigate its interaction with a human body and achieve a high-efficiency power transfer at a short range. Our proposed system is based on a grounded loop to reduce the leakage of the electric field, resulting in less interaction with the human body. As a result, a transmission efficiency higher than 70% is achieved at a transmission distance of approximately 25 cm. Under the maximum-efficiency conditions of the WPT system, the use of a resonator with a grounded loop reduces the induced electric field, the peak spatial-average specific absorption rate (psSAR), and the whole-body averaged SAR by 43.6%, 69.7%, and 65.6%, respectively. The maximum permissible input power values for the proposed WPT systems are 40 and 33.5 kW, as prescribed in the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines to comply with the limits for local and whole-body average SAR.
作成者 : Duan Xianyi | Lan Junqing | Diao Yinliang | Gomez-Tames Jose | Hirayama Hiroshi | 堀田 昌志 | Fischer George | Hirata Akimasa 出版者 : MDPI AG 発行日 : 2021-11-03
The power transmission effi ciency of a resonatorcoupled wireless power transfer (RC-WPT) system with some angular misalignments is examined in this paper. In addition to conventional single-spiral resonators, the dual-spiral resonators which we have proposed are used in the RC-WPT system. It was confi rmed that the power transmission effi ciency of the RC-WPT system decreased with the increment of angular misalignments. However, it was shown that the decayed power transmission efficiency due to the angular misalignments could be recovered by adding the appropriate axial displac ements between transmitting (Tx) and receiving (Rx) units.
作成者 : Nur Syafiera Azreen Norodin | 堀田 昌志 出版者 : Union Radio-Scientifique Internationale 発行日 : 2020-10-26
In presented work dye assemblies with J-type intermolecular coupling, which are well recognized not only for their exciton transport but also for hole and electron transport properties were investigated. The use of materials consisting of J-type dye assemblies can be significantly enhanced if their photonic properties can be controlled by some external stimuli. For these reasons the switching abilities between J-type aggregated and non-aggregated states of a cationic cyanine dye, 1,1′-diethyl-2,2′-cyanine (pseudoisocyanine, PIC) intercalated in the interlayer space of synthetic saponite (Sap) were compared. The switching was performed by adding and removing of dimethyl sulfoxide (DMSO) from the interlayer space. The PIC/Sap hybrid film prepared at 70% CEC loading level has shown excellent stability within 20 cycles of photophysical response after adding and removing of DMSO from the interlayer space, indicating that presented experimental approach can be useful in the future development of artificial light harvesting or semiconductor systems with controllable properties.
作成者 : Marian Matejdes | 姫野 大輔 | 鈴木 康孝 | 川俣 純 出版者 : Elsevier B.V. All 発行日 : 2017-05
The interlayer space of clays is an interesting microenvironment to control the properties of included organic materials. In this study, chromic hybrid films consisting of synthetic saponite (SSA) and fluorescent organic molecules with planar p-conjugated systems were fabricated. The hybrid films exhibited reversible fluorescence color switching induced by swelling and drying, which caused the gallery height of SSA to change. Ultraviolet–visible absorption, steady-state and time-resolved fluorescence measurements of the hybrid films strongly suggested that the organic molecules formed an excimer in the swollen interlayer space of SSA, while they were a monomer in the dried interlayer space. The different emission wavelengths of the excimer and monomer resulted in the fluorescence color switching of the hybrid films. The reversibility of the color switching was maintained for at least 50 cycles with no change of fluorescence maxima. These chromic hybrid films represent a novel approach to obtain color switching.
作成者 : 富永 亮 | 鬼木 悠大 | 持田 修平 | 笠谷 和男 | 谷 誠治 | 鈴木 康孝 | 川俣 純 出版者 : American Chemical Society 発行日 : 2016-09-30
Ferroelectrics have found a wide range of applications including memory elements, capacitors, and sensors. Molecular f erroelectric crystals have recently attracted growing interest as viable alternatives for conventional ceramic ferroelectrics, especially due to their non toxicity and solution processability. Herein, we show that a class of molecular compounds known as plastic crystals can exhibit ferroelectricity, provided that the constituent molecules are judiciously chosen from polar ionic molecules. The intrinsic features of plastic crystals, e.g. the rotational mot ion of molecules and phase transitions with lattice symmetry changes, provide the crystals with unique ferroelectric properties relative to conventional molecular crystals , i.e. the possibility to flexibly alter the direction of the polarization axis of a grown crystal by applying an electric field. Owing to t he tunability of the crystal orientation together with mechanical deformability, this novel type of molecular crystals represents an attractive functional material, which will undoubtedly find diverse applications.
作成者 : Harada Jun | Shimojo Takafumi | Oyamaguchi Hideaki | Hasegawa Hiroyuki | Takahashi Yukihiro | 里見 浩一郎 | 鈴木 康孝 | 川俣 純 | Inabe Tamotsu 出版者 : Nature Publishing Group 発行日 : 2016-10
Near-infrared two-photon absorption of the phosphorescent Ir(III) complex (2,4-pentanedionato-κO2,κO4)bis[2-(6-phenanthridinyl-κN)benzo[b]thien-3-yl-κC]iridium (BTPHSA) was characterized. It exhibited a 800–1200 nm two-photon absorption band, and thus could be electronically excited by 1030-nm femtosecond Ti:sapphire and Yb-doped fiber lasers. By using BTPHSA, oxygen concentrations in human embryonic kidney 293 (HEK293) cells were imaged. These results demonstrate two-photon oxygen sensing of live tissues via easily operable excitation sources.
作成者 : 守友 博紀 | 藤井 旺成 | 鈴木 康孝 | Yoshihara Toshitada | Tobita Seiji | 川俣 純 出版者 : 公益社団法人応用物理学会 発行日 : 2016
We measured the three-photon absorption spectra of two europium acetylacetonate-type complexes. The three-photon absorption peak wavelengths of tris(hexafluoroacetylacetonato)europium(III) (Eu(hfa)) and tris(2-naphthoyltrifluoroacetonato)europium(III) (Eu(ntfa)) were 925 and 1025 nm, respectively. The peak values of the 3PA cross-sections of Eu(hfa) and Eu(ntfa) were 1.9 and 13.9 GM (1 GM = 10−82 cm6 s2), respectively. Using Eu(ntfa) as a probe, a three-photon microscope image of a living cell was obtained using a 1030 nm operating femto-second fiber laser as the light-source. Thus, Eu(ntfa) is a fiber laser excitable luminescent probe useful for three-photon microscopy.
作成者 : 鈴木 康孝 | 守友 博紀 | 藤井 旺成 | 里見 浩一郎 | 川俣 純 | Yamamoto Masanori | Hasegawa Yasuchika 出版者 : 公益社団法人日本化学会 発行日 : 2016
We have found that X-ray diffraction peaks of clay-organic hybrid films were narrowed after swelling followed by removing of solvent. We fabricated hybrid films consisting of natural montmorillonite (Mont), synthetic saponite (SSA) or synthetic stevensite (SST) and a cationic organic molecule. Full width at half maximum (FWHM) of 001 reflection of as-prepared Mont hybrid was 1.58 2θ degree whereas that after swelling and solvent removing procedure was 0.84 2θ degree. This decreasing of FWHM indicated that the improvement of packing order of clay particles in clay-organic hybrid was occurred during swelling and solvent removing procedure. Similar decreasing of FWHM was also found in hybrids consisting of SSA or SST. Improvement of packing order of hybrid was found to accompany suppression of light scattering of hybrid at the same time.
作成者 : 鈴木 康孝 | 姫野 大輔 | 富永 亮 | 谷 誠治 | 野崎 浩二 | 川俣 純 出版者 : 一般社団法人日本粘土学会 発行日 : 2015
Unbeatable tit-for-tat as a zero-determinant strategy
Journal of the physical society of Japan 91 巻
作成者 : 上田 仁彦 出版者 : Physical Society of Japan 発行日 : 2022-04-21
症例は38歳女性,左臀部痛を主訴に当院を受診.造影CT・MRIで腰椎L5・仙骨前面に小腸・腸間膜と近接する7cmの表面平滑な腫瘤を認めた.小腸GISTが疑われたが確定診断には至らず,診断・治療目的に腹腔鏡手術を施行する方針とした.審査腹腔鏡にて小腸に病変はなく,大動脈分岐部仙骨前面後腹膜に腫瘤を認め後腹膜腫瘍と診断した.画像検査で周囲に浸潤はなく,術中所見でも表面平滑で可動性があり,腹腔鏡下に切除を行う方針とした.S状結腸間膜を切開し下腹神経前筋膜を温存,腫瘍を周囲から剥離し切除した.合併症なく自宅退院,病理診断は良性神経鞘腫で再発なく経過している.仙骨前面後腹膜神経鞘腫は稀であり,術前に確定診断に至らない場合もある.本症例は審査腹腔鏡が局在診断に有用であり,一期的に切除が可能であった.腹腔鏡下切除した仙骨前面巨大後腹膜神経鞘腫の1例を経験し,文献的考察を加え報告する.
作成者 : 小佐々 貴博 | 的場 勝弘 | 中津 宏基 | 北澤 荘平 出版者 : 山口大学医学会 発行日 : 2022-02-22
症例は52歳男性.来院3日前からの右下腹部痛を主訴に当科を受診,造影CT検査で膿瘍形成を伴う虫垂腫大を認め,腹腔内膿瘍を伴う複雑性虫垂炎と診断した.保存的加療を行った後に待機的に虫垂切除を施行する方針とし,抗菌薬治療を開始した.治療開始後の経過は良好で,第19病日に自宅退院となった.発症6ヵ月後に待機的に腹腔鏡下虫垂切除術を施行,合併症なく経過し術後7日目に自宅退院となった.切除標本は肉眼的に軽度の粘膜浮腫を認めるのみであったが,病理組織学検査で虫垂goblet cell adenocarcinoma(以下,虫垂GCA)の診断となった.深達度T4a,リンパ管侵襲陽性でありリンパ節転移の可能性があったため,初回手術から1ヵ月後に回盲部切除(D3)を施行した.合併症なく経過し術後20日目に自宅退院となった.術後病理組織学的検査結果はpT4aN0M0 pStage IIであった.術後18ヵ月経過した現在,再発は認めていない.本症例は複雑性虫垂炎保存的加療後の虫垂切除術後標本から偶発的に発見された虫垂GCAで,根治的に回盲部切除(D3)を施行し得た1例であった.昨今,急性虫垂炎は保存的加療が選択されることもあり,待機的に根治切除が施行されない場合もある.複雑性虫垂炎においては有意に虫垂腫瘍の合併が多いという報告もあり,虫垂GCAにおいてはリンパ節転移を伴う可能性を考え,大腸癌に準じた追加切除が必要となる.実臨床において虫垂炎保存的加療後すべてに待機的虫垂切除を行うことは難しいが,複雑性虫垂炎保存的加療後には,年齢,ADL,社会的背景を考慮した上で,虫垂GCAを含む虫垂腫瘍を合併している可能性を考慮し,待機的虫垂切除術施行を検討する必要があると考えられた.
作成者 : 小佐々 貴博 | 的場 勝弘 | 中津 宏基 | 北澤 荘平 出版者 : 山口大学医学会 発行日 : 2022-02-22
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