Real-Time Reactions in Supervisory Control According to Data Freshness

Supervisory control systems in plants mustacquire data without any loss and react for state changes. Someof state change should be reacted in a real-time manner, whileothers may be notified in a best-effort manner. To implementa middleware which works as a server in supervisory control systemsin an acceptable cost, we value the data freshness which meanshow much time has passed from the occurrence of the data. Inthis paper, we present the Active Ring model whichincorporates the ECA mechanism into circular areas. With rulesusing only the latest data, the ECA mechanism realizes time-criticalreactions as firm real-time tasks. In addition to that, the rulestrigger best-effort notification which is realized as a softreal-time task. The middleware works in numerous plants for steelmill, water purifying, and tunnel ventilation. This paper includesan experimental result revealing that the ActiveRing model is effective to provide service according to the datafreshness.     

The influences of mesh subdivision on nonlinear fracture analysis for surface cracked structures

The leak-before-break (LBB) concept can be expected to be applied not only to safety assessment, but also to the rationalization of nuclear power plants. The development of the method to evaluate fracture characteristics is required to establish this concept. The finite element method (FEM) is one of the most useful tools for this evaluation. However, the influences of various factors on the solution are not well understood and reliability has not been verified enough. In this study, elastic-plastic 3D analyses are performed for two kinds of surface cracked structure, and the influences of mesh design are discussed. The first problem is for surface crack growth in a carbon steel plate subjected to tension loading. A crack extension analysis is performed under the generation phase simulation using the crack release technique. The numerical instability of the J-integral solution is observed when the number of elements in the thickness direction of the ligament is reduced to three. The influence of mesh design in the ligament on the solution is discussed. The second problem is for a circumferential part-through crack in a carbon steel pipe subjected to a bending moment. Two kinds of mesh design are employed, and a comparison between two sets of results shows that the number of elements on the crack surface also affects solution as well as the number of elements in the ligament.     

Thickness‐Dependent Structure–Property Relationships in Strained (110) SrRuO3 Thin Films

Thickness‐dependent structure–property relationships in strained SrRuO₃ thin films on GdScO₃ (GSO) substrates are reported. The film is found to have epitaxially stabilized crystal structures that vary with the film thickness. Below 16 nm, the √2a_pc × √2a_pc × 2a_pc monoclinic structure is stabilized while above 16 nm the film has the a_pc × 2a_pc × a_pc tetragonal structure. The thickness‐dependent structural changes are ascribed to the substrate‐induced modification in the RuO₆ octahedral rotation pattern, which highlights the significance of the octahedral rotations for the epitaxial strain accommodation in the coherently‐grown films. Close relationships between the structural and physical properties of the films are also found. The monoclinic film has the uniaxial magnetic easy axis 45° away from the [110]_GSO direction while the tetragonal film has the one that lies along the in‐plane [1–10]_GSO direction. The results demonstrate that the octahedral rotations in the strained perovskite oxide thin films are a key factor for determining their structure phases and physical properties.     

Round-robin activities on finite element analyses of elastic-plastic fracture in Japan

The establishment of the leak-before-break (LBB) concept requires a method to evaluate the fracture characteristics. The finite element method can be used for this purpose but the solution is more or less influenced by the method employed. In this study, two round-robin analyses are performed for three-dimensional crack problems. The first problem is for surface crack growth in a carbon steel plate subjected to tension loading. Ten solutions are obtained by ten participants, and calculated results are compared with each other as to the applied load, displacement and J-integral. Though the relation between applied load and displacement is affected by modeling of the stress-strain curve, fairly good agreement is obtained between the solutions. The second problem is for a circumferential part-through crack in a carbon steel pipe subjected to a bending moment. Nine solutions are obtained by eight participants. The difference between the solutions is relatively significant as to the relation between J-integral and load-point displacement. A discussion is made about the sources of difference between each solution.     

Analytical evaluation method of J-integral in creep-fatigue fracture for type 304 stainless steel

Creep-fatigue crack growth at the operating temperature of LMFBR can be characterized by ΔJ_F and J′ (same as C^*). Type 304 stainless steel, the main structural material of the Japanese LMFBR, shows notable cyclic hardening at elevated temperatures. Evaluation of these J-integrals with the finite-element method is strongly affected by the reference strain range when the cyclic hysteresis' is used as the stress-strain relation.In this paper, an evaluation method for ΔJ_F and J′ with a cyclic stress-strain curve (Δσ – Δ relation) is proposed and verified by experimental results. The evaluation method proposed here does not require cyclic calculations but is monotonic and the effect of the reference strain range is relatively small.     

Electronic and optical properties of hydrogenated microcrystalline silicon: review

Current understanding of electronic transport and optical properties of hydrogenated microcrystalline Si (c-Si : H) prepared by plasma enhanced chemical vapor deposition are briefly reviewed. Research to date shows that the effective-medium approximation is a useful model in understanding the physical properties of c-Si : H.     

Evaluation of Bifidobacterium breve strain Yakult-fermented soymilk as a probiotic food

We evaluated the effects of Bifidobacterium breve-fermented soymilk on probiotic function. An administered strain of B. breve strain Yakult was capable of growing in soymilk with no additives as high as 10(9) CFU/ml. During storage of the fermented soymilk at 10 degrees C for 20 days, viable counts of the strain did not change. The growth inhibition of the strain in a bile-containing medium was lessened by the addition of soy protein. In human feeding experiments, the administered B. breve was recovered at a level of over 10(9) CFU/g faeces, accompanied by an increase in the total number of bifidobacteria. These results indicate that fermented soymilk with B. breve strain Yakult could be a novel type of probiotic food.