Recently, there has been a growing interest in developing evolutionary algorithms based on probabilistic modeling. They are called probabilistic model-building genetic algorithms (PMBGAs) or estimation of distribution algorithms (EDAs). In this scheme, the offspring population is generated according to the estimated probability density model of the parent instead of using recombination and mutation operators. In this paper, we have proposed PMBGAs in permutation domains using edge histogram based sampling algorithms (EHBSAs). Two types of sampling algorithms, without template (EHBSA/WO) and with template (EHBSA/WT), are presented. The results were tested in the TSP and showed EHBSA/WT worked fairly well with a small population size in the test problems used. It also worked better than well-known traditional two-parent recombination operators.

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主双対内点法に基づく接触解析手法は, 従来の有効制約法に比べ, 接触制約が多数存在するような接触問題に対して有利であるとされ, 近年注目されている. 一方で, 主双対内点法に基づく接触解析手法を有限変形, 特に大変形を伴うような増分解析が必要となる問題に適用する場合, Newton-Raphson (NR) 法反復の初期段階で強い接触反力が生じて計算が不安定になるという問題があった. 本論文ではこの問題を解決するために, 主双対内点法に基づく接触解析手法にウォームスタート法を導入し, NR 法反復の初期段階における接触制約を緩和する手法を提案する. 接触解析における提案手法の収束性を検証するため, 大変形問題を含む種々の問題を解き計算に要した NR 法反復の回数を比較した. 検証の結果, 提案手法は主双対内点法や有効制約法に基づく接触解析手法に比べ収束性に優れることを確認した.

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In this paper, we describe a GA system based on variable length chromosomes. Our goal is to establish "analog evolvable hardware", i. e., analog EHW.Analog hardware is vulnerable to the environment, such as temperature, and traditional methods to deal with the environmental disturbance are complicated and ad-hoc so that they are not fit for designing a large-scale circuit. In the EHW approach, noises and errors are fed back from the manufacturing process to the designing process. These processes are repeated until the adapted hardware is acquired. Thus, the EHW is robust to the external disturbance. This paper introduces a new approach to the analog EHW. We use a component-list representation, which has the advantage of enabling the design flexibility, i. e., the capability of acquiring more various functions. We can also properly size a circuit without designer's specification. Our system also features the two-stage evolution, i. e., the structural adaptation of the circuit topology and the parameter adaptation by tuning up the elements'values. This division is aimed at achieving more efficient global search with local modification. We show experiments which support the superiority of our approach over conventional approaches in terms of robustness and computational cost.

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The Maximum Entropy Method (MEM) can provide a high-resolution nuclear density distribution purely from experimental neutron diffraction data. The distribution expresses thermal smearing, which is caused by all kinds of thermal-vibration modes both harmonic and anharmonic. If the effective one-particle potential (OPP) is assumed to describe thermal smearing of nuclei, the potential parameters can be determined by least squares refinement of the nuclear density distribution. It is found that this technique gives sufficiently small correlation between potential parameters than the conventional structure analysis technique and the potential parameters can be precisely determined even in a powder diffraction case.

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蜜蜂は社会性昆虫の一種であり，複数の蜜源に対し８の字ダンスを用いて適切な採蜜蜂の割り振りを行うことで有名である．しかし，採蜜蜂が貯蔵蜂との連携において採蜜蜂同士の採蜜基準自体を自律的に調整させていることはあまり知られていない．本研究ではこの採蜜基準の自動調整を模した閾値の調整を取り入れた最適化アルゴリズム Bee Total Optimization with Personal Judgment（BTO-PJ）を提案する．BTO-PJ はマルチエージェントシステムであり，採蜜蜂を模したエージェントは他のエージェントとの情報交換によって最適解を探索する．これを巡回セールスマン問題に適用した結果を示した．

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Large earthquakes along the subducting plate boundary occur repeatedly in the area of an asperity that consists of a strongly coupled zone between two plates. Other areas along the subduction zone are considered to be stable-quasi-stable slip region, which is called a non-asperity, might release strain energy caused by oceanic plate subduction. The physical states of large asperities under the ocean are not well known at present because of the lack of offshore stationary observation networks (e.g., geodetic, seismic and electromagnetic networks).
Strong PP reflections from the subducting plate boundary were found in aseismic zones along the Japan Trench and in the slow slip region in the Tokai region. These features suggest the presence of low-Vp/soft materials and/or fluid along the subducting plate boundary. Such regions might cause continuous or intermittent aseismic slow-slips. If we can map areas of strong PP reflections from observations such as refraction-reflection studies using Ocean Bottom Seismometer (OBS) -airgun surveys, we will be able to obtain the distribution of asperities along the plate boundary.
Assuming that slip acceleration at non-asperity regions might trigger a large earthquake at adjacent asperities, a sudden change of physical states in a non-asperity region might suggest a high probability of plate-boundary earthquakes. Changes due to slip acceleration might be detected by continuously monitoring seismic reflection intensity at non-asperity regions. To perform continuous monitoring, we propose the Accurately Controlled Routinely Operated Signal System (ACROSS), with an integrated active monitoring method using continuously transmitting seismic and electromagnetic sinusoidal waves, which are accurately controlledby a GPS clock with a sophisticated signal analysis method.
The ACROSS seismic source at Toki city in central Japan has been operated continuously for more than 2 years. A field experiment in the Tokai region, central Japan, using this transmission method provided sufficient S/N ratios for the Pg phase traveling 60 km through stacking the data for one month.
Submarine cable OBS systems near the trenches enable us to continuously monitor seismic reflection signatures provided by ACROSS systems located on land. The planned submarine cable OBS in the Tonankaki region might be a good real-time receiver system.
The Exploration of Asperities-Reflectors System (EARS) is proposed for integrating the necessary research components-mapping, monitoring, and real-time continuous monitoring of the Earth's crust. In this paper, we describe the analytical method and important points in such a study.

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