The Tokyo Metropolitan Government established “Seaside park plan” (1970) and “Tokyo municipal seaside park ordinance” (1975). The Tokyo Metropolitan Government considers that the conservation of seaside, riverside and urban parks make the creation of places where residents of Tokyo can come in contact with nature. However, it seems that the planning and construction of those parks have been carried out by the administration from one-side view. The waterfront parks are public and have been used by many people. As there have been no data what components of parks are important for users of parks, eight seaside parks called waterfront parks were watched, degrees of satisfactory of eighty two residents who live in metropolitan area about components of parks were surveyed, and degrees of concern about components of the parks have been obtained by conjoint analysis. Those waterfront parks are located at Odaiba near the Tokyo bay. Here, the components of parks are as follows; 1) Hydrophile, 2)Rest space, 3) Public transport and conditions of location, 4) Recreation, 5) Scenery and outlook, 6) Maintenance, 7) Monument, and 8) Openness. The following main results have been obtained from the research.: a) Male and female think scenery and outlook, and hydrophile are important. b) Rest space is less important than other components for the twenties, but important for the thirties, forties and sixties. c) Public transport and location is not much important for teenager, but important for the others. d) The fifties make a point 1) Hydrophile, 3) Public transport and condition of location, and 5) Scenery and outlook.

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A Voronoi diagram is useful to make a city plan and analyze location of public facilities, for example it is used for determining an elementary school zone, a commercial area of shopping center and an evacuation area of disaster, etc. The Voronoi diagram is generally determined by the clear boundary line, called Voronoi edge. However, when the adaptation of Voronoi diagram to a city planning like previous examples is considered, the boundary with width belonging to both of the Voronoi areas: an ambiguous boundary, is more effective than the clear line boundary. Tow kind of “difference between distances” are used to make an ambiguous boundary on this paper. One is absolute difference between distances; another is relative difference between distances. The simulated area is made of a set of cells divided by the tetragonal lattice. So the area is a discrete space that consists of cells. The discrete space makes it easy to make up the algorithm of a digital Voronoi diagram with ambiguous boundaries. On this paper, the characteristics of the Voronoi diagram with ambiguous boundaries of two generators are considered at first. Next, the cases of more generators are examined and the quantity characteristics are clarified.

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In this paper, we consider the problem for determining an optimal location of a line facility in a city such as railway system. A line facility is modeled as a spanning tree embedded on the plane whose vertices represent stations and edges represent the rails connecting two stations, and people can travel not only by walk but also by using the line facility quickly. Suppose there are a finite number of towns in a city, only in which people lives. Then, our problem is to find a location of the stations as well as a connection of the stations such that the sum of travel time between all pairs of towns is minimum. Tsukamoto, Katoh and Takizawa proposed a heuristic algorithm for the problem which consists of two phases as follows. In the first phase, fixing the position of stations, it determines the topology of the line facility. The second phase optimizes the position of stations while the topology is fixed. The algorithm alternately executes these two phases until a converged solution is obtained. Tsukamoto et al. determined the topology of the line facility by solving minimum spanning tree (MST) in the first phase. In this paper, we propose two methods for determining the topology of the line facility so that the sum of travel time is minimized hoping to improving the previous algorithm. The first proposed method heuristically determine the topology by using evolutionary algorithm (EA). In the second method, we reduce our problem to minimum communication spanning tree (MCST) problem by making a further assumption, and solve it by formulating the problem as an integer program. We show the effectiveness of our proposed algorithm through the numerical experiments.

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In this paper, a multiple optimization system using genetic algorithms is proposed. Using this system, plural objectives with mutually differing evaluation criteria can co-evolve and co-exist according to given overall conditions. Three case study simulations are performed in which three architectural spaces are formed using a cellular automata model and the L-system within a building site under the following conditions: internal conditions— stability, density, aspect ratio, and natural lighting; and external conditions— building coverage and floor area ratio. For these case studies, results showed that these three architectural spaces can co-evolve and co-exist autonomously, adapting to external site conditions using the proposed multiple optimization system.

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The authors have already proposed an intelligent fuzzy optimal and active control system (IFOACS) and the effectiveness of IFOACS was proved using digital simulations and shaking table tests. However, the results show that the control effect of IFOACS becomes small in case of near-source region earthquakes. To improve control effects in case of near-source region earthquakes, a combinatorial control system (CCS), in which IFOACS is combined with a fuzzy active control system (FACS), is also proposed. In this paper, control rules in CCS are optimized using parameter-free genetic algorithms (PfGAs) considering limitations of an actuator such as maximal strokes and control forces. Effectiveness of proposed combinatorial control system (CCS) is verified and discussed based on results of digital simulations.

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There are many studies on base isolation and seismic isolation of structures. In order to clarify experimentally, the efficiency of variable stiffness control that has been considered using numerical simulation, a variable stiffness structure using a clutch system was made. A simple on-off control with a clutch mechanism of a variable stiffness structure to the magnitudes of acceleration has been proposed. This control method was examined in the research.
Using this method, when the vibration acceleration amplitude is large, the clutch is connected to the additional structure saving potential energy in the additional structure, and when the vibration acceleration amplitude decreases, the clutch is disconnected from the additional structure releasing the potential energy at once and attenuating the displacement amplitude of vibration, so that the vibration can be decreased effectively.

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