Simulated annealing and its application to cobb-douglas economic model

Recently, the simulated annealing has been applied to several combinatorial optimization problems. In this paper, the simulated annealing method for continuous functions is reviewed, and it is applied to an economic model having multiple optimal solutions, in which all optimal solutions cannot be simultaneously obtained by Scarf's algorithm.     

Review of the International Symposium on Artificial Life and Robotics (AROB)

In this article, we review the growth of AROB conferences, and assess the various contributions, which have covered digital life, the artificial brain, artificial society, and evolutionary robots, etc. We analyze the relations between artificial life, complexity, and intelligent robots, and finally give our view of the expected future of AROB. This work was presented in part at the 5th International Symposium on Artificial Life and Robotics, Oita, Japan, January 26–28, 2000     

The evaluation of air transportation network based on multiple criteria

The problem is partitioned into two components: to propose the air transportation network based on “hub and spoke” pattern as alternative network in Sumatera island (one of the islands in Indonesia), and to propose the algorithm for the aircraft selection of the suitable type of aircraft in the operation on airport pairs. The algorithm presented in this paper is obtained from heuristic, and then comparing of our proposal with the existing one is done, based on the multiple criteria.     

Computation of mutual entropy in quantum markov chains

There are several damping phenomena in quantum optics. Such phenomena have been usually explained by open systems. In statistical physics, open system dynamics have been used to study the irreversibility and the approach to equilibrium. In this paper, the dynamical change of the mutual entropy for an open system, frequently studied in the quantum optics literature, is rigorously computed through a model of quantum Markov chain. In particular, the concrete formula of Stinespring expression for such a model is obtained and applied to the derivation of the mutual entropy, and some computational results are presented.     

A new artificial life body: biologically inspired dynamic bipedal humanoid robots

Recently, a biologically inspired, bipedal, dynamic, humanoid robot was developed at the Artificial Life and Robotics Laboratory of Oita University. This bipedal humanoid robot is able to walk dynamically and to go up and down stairs. The central pattern generator developed produces various types of walking pattern. This robot has a pair of small CMOS color CCD cameras, a speaker, and a microphone in the head part, and will have a GPS, a portable telephone, and other sensors in the body part, so that the integration of locomotion and behavior to achieve specific demonstrations will be realized. This project develops dynamic mobility and the ability for autonomous recognition and navigation using the biological central nervous system, the brain system, and the real-time control system. Also, the design principles that demonstrate the dynamic interaction between neural and mechanical controls will be clarified. In Phase I, the platform of a small, bipedal, humanoid robot is used to develop autonomous locomotion and autonomous sensing and navigation. In Phase II of the project, an iteration on the platform design for human-size, bipedal, humanoid robots will be performed for operational testing. The development of bipedal humanoid robots that capture biological systems with unique principles and practices could dramatically increase their performance in tasks for national security needs.This work was presented in part at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003     

Numerical computation of thermally controlled steam bubble condensation using Moving Particle Semi-implicit (MPS) method

In the present study, single steam bubble condensation behaviors in subcooled water have been simulated using Moving Particle Semi-implicit (MPS) method. The liquid phase was modeled using moving particles and the two phase interface was set to be a movable boundary which can be tracked by the topological position of the interfacial particles. The interfacial heat transfer was determined according to the heat conduction through the interfacial liquid layer and the coupling between momentum and energy was specially treated. Computational results showed that the bubble experiences various deformations at lower degrees of liquid subcooling while it remains nearly spherical at higher degrees of liquid subcooling. The bubble lifetime is nearly proportional to bubble size and is prolonged at higher system pressures. Bubble lifetime obtained from the MPS method agrees well with the experiments of 10 and 11, however it is lower than the predictions of Sudhoff et al. (1982). The underestimation is caused by severe bubble deformation at lower degrees of subcooling. The present study exhibits some fundamental characteristics of single steam bubble condensation and is expected to be instructive for further applications of the MPS method to evaluate more complicated bubble dynamics problems.     

Corrosion evaluation of Au-Cu-Pd ternary alloys

The corrosion resistivity of single-phase Au-Cu-11 at% Pd alloys was evaluated by using a parameterQ which represented the total amount of anodic reaction in a potentiostatic polarization test. The result was compared with those for binary Au-Cu, ternary Au-Cu-11 at % Ag and some commercial alloys. The validity of usingQ as a corrosion parameter was confirmed by the good agreement between the analysed and calculated values of copper ion dissolved into the test solution. By replacing a part of the copper in Au-Cu alloys with palladium the corrosion resistivity can be greatly improved, but silver has no such significant effect. The value ofQ decreased by both treatments of homogenization and grain refinement of the alloy. One of the advantages of the alloy having a single-phase structure is that inhomogeneity in the distribution of the constituents is small even in the as-cast state, which results in a small galvanic effect.     

Preparation of spherical fine ZnO particles by the spray pyrolysis method using ultrasonic atomization techniques

An ultrasonic atomizer was used in the spray pyrolysis method to prepare fine, spherical and uniform ZnO particles. Almost spherical particles were obtained successfully which had a mean particle size of 0.15 m and had a very narrow particle size distribution. By using alcohol as the solvent, it was found that the particles do not have hollow shell layers which could usually be observed in the spray pyrolysis process by using water as the solvent. The morphology of the ZnO particles was strongly affected by the concentration of the starting solution.