Two-way deterministic multi-weak-counter machines

In this paper, we consider two-way deterministic machines which have counters, each capable of storing any nonnegative integer, but not having the ability to detect empty counter, and which accept by final state. We call these machines two-way deterministic multi-weak-counter machines. Let 2NWC^(k) and 2DWC^(k) denote the classes of languages recognized by two-way nondeterministic and deterministic k-weak-counter machines, respectively. In particular, for k = 1, we denote the corresponding classes by 2NWC and 2DWC. The following results are shown: (1) 2DWC^(k) = 2DWCfork ?1. (2) A bounded language in 2DWC is a bounded semilinear language. (3) 2NWC ≠ 2DWC.     

A logical basis for programming methodology

In this paper, the relation between WHILE-programs and formal proofs of their quantified specification is studied. This gives us a logical basis for programming methodology since the programming concepts such as assignment statements, IF-statements and WHILE-statements are fully explained logically, here ‘logically’ means ‘how to think’. As an example, Hoare's program FIND is studied methodologically.     

On the reaction between UO2 and Zr

The reaction between UO₂ and Zr has been studied from both equilibrium and kinetic points of view. In the equilibrium study, the reaction of UO₂ with Zr with several Zr/UO₂ mole ratios has been made at 1000°C and the products have been identified using X-ray diffraction method. The interfacial reaction zones after the heat-treatment of the reaction couples of UO₂ pellet and Zr sheet have been studied using a SEM.     

Development of multicomponent vaporization/condensation model for a reactor safety analysis code SIMMER-III: Extended verification using multi-bubble condensation experiment

Complex phenomena such as phase transitions and heat transfers in multiphase, multicomponent flows were modeled in the fluid-dynamics portion of SIMMER-III, which was developed to appropriately assess core disruptive accidents (CDAs) in liquid–metal fast reactors (LMFRs). A new multicomponent vaporization/condensation (V/C) model was developed and introduced to SIMMER-III by the authors. In the present study, a new series of multi-bubble condensation experiments was performed to demonstrate that SIMMER-III with the present V/C model is practically applicable to multicomponent, multiphase flow systems with phase transition. In the experiments, bubble diameters and void fractions were quantified from visualization images using original image-processing techniques. Comparing SIMMER-III predictions with experimental data, it was confirmed that SIMMER-III with the proposed V/C model could suitably represent the effects of noncondensable components on the condensation process in multi-bubble systems. This work has improved the reliability of SIMMER-III with regard to multicomponent phase-transition phenomena.     

Decentralized exciter stabilizing control for multimachine power systems

In this paper, a systematic approach to design controllers based on H‐infinity theory for a multimachine power system is presented. Generally, a centralized control scheme is difficult for a large‐scale interconnected power system because of the necessity of obtaining information on the whole system, computation times, and so on. In order to handle these problems, two decentralized control schemes are proposed. One is based on the decomposition of information. The feedback gains for the whole system are obtained, and after decomposing the gains into subblocks for each area, the diagonal block is used to design the controller for each generator. The other is based on area decompositions. The procedure is carried out by decomposing the original system into blocks for each area and the local feedback gain is obtained by using information for each decomposed system. Furthermore, to improve the robustness of the system, an effective weighting matrix design, which involves the allocation of eigenvalues, is also proposed. Several simulation tests show the effectiveness of the proposed methods. © 2002 Scripta Technica, Electr Eng Jpn, 139(1): 35–43, 2002; DOI 10.1002/eej.1144     

Preferential supporting of potassium carbonate around the peripheral region of activated carbon fibre

Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.     

Structure and properties of highly crystallized graphite films based on polyimide Kapton

Highly crystallized graphite films were prepared by heat treatment of carbonized polyimide films (Kapton) at temperatures of 2700 and 3050° C. Interlayer spacing d ₀₀₂ at room temperature, and electrical resistivity, magnetoresistance and Hall coefficient at room and liquid nitrogen temperatures were measured. All of these data indicate high crystallinity of the graphitized Kapton films obtained. For the graphite films heat treated at 3050° C mean-square mobilities were estimated from the magnetoresistance data at 1 T to be 0.91 m² V^–1 sec^–1 at room temperature and 2.3 m² V^–1 sec^–1 at liquid nitrogen temperature; the value at liquid nitrogen temperature corresponds to that for a pyrolytic graphite heat treated at 3200° C for 1 h (PG 3200). Magnetic field dependence of Hall coefficient at liquid nitrogen temperature for this sample also agrees well with that for PG 3200. Scanning electron micrographs on the surfaces show that the present graphite films consist of grains of large crystallites, and grain size increases as the crystallinity of the material improves.     

John Lewis商场影院综合体

商场影院综合体项目属于市中心复兴计划的一部分．改变了建筑传统的平坦外形．开创了将建筑群体融入城市肌理的新途径。设计使用一系列的文化和历史元素激活街区，创造莱切斯特地区独特的建筑群体，并为游客和路人提供特殊的购物和休闲体验。     

Humidity Sensitive Electrical Conduction of ZnO-Ni1-xLixO Heterocontacts

Heterocontacts of p-n semiconductors were produced by mechanically pressing together polished surfaces of ZnO and Ni_1-xLi_xO sintered pellets. The electrical conductivity of the heterocontacts was highly sensitive to humidity. The sensitivity to changes in humidity was dependent on the surface finish of the pellets, the lithium dopant level in the NiO ceramic, and the porosity of the ZnO ceramic.