Hirotaka Suzuki

• PhD
• Professor at Kobe University

Until now, lampshade design methods that utilize basic four-dimensional shapes such as hypercubes had been proposed. The author extended this method and proposed lampshade design methods based on the shape of a general super-prism and the shape of rotated polytopes. In addition to a method of utilizing super prism with a cube and a quadrangular pyr...

We investigate the behaviour of a new-type daylighting system composed of concave and convex paraboloidal mirrors. This system realises converting parallel light into highly-dense parallel before passing through the focal point. It means that the system solves one of the significant problems in daylighting systems: heat problems. In this paper, we...

Lampshades were developed as wind shield for light source when fire was used for light source. Though contemporary light sources, like LED lamp, fluorescent lamp and incandescent light, are working with electricity and wind shield is not required for light source, almost all light sources are still covered by lampshade to arrange or control luminou...

This is the accepted manuscript to be published as a Technical Note in the International Journal of Acoustics and Vibration (published by IIAV). Will be published soon in Vol. 22, No. 2. pp 1-6 (2020) If anyone needs to cite this preprint, please add the journal name properly and indicate as “to be published “. After the formal publication this...

The authors propose a space sound absorber made of a permeable membrane (PM), including woven or non-woven fabrics in three-dimensional shapes, e.g., cylinder, rectangle, etc. The proposed absorbers are examined by experimental measurements and boundary element analyses, and it is found that they can be effectively used especially for middle and hi...

In the field of lampshade design, paper folding method has been highly utilized as the non-flat texture by paper folding method can generate beautiful luminance distribution. And a method combining non-flat pattern and geometrical transmittance pattern has been already proposed to overlap luminance distribution caused by non-flat texture and that b...

We perform two-dimensional raytracing simulations of our revolutionary daylighting system for each latitude from 0˚ to 90˚. In previous paper, we check behaviour of our new-type afocal day-lighting system and show performance of our system at latitude 30˚. The innovative daylighing system is optimised at latitude 30˚. In this paper, we investigate...

In the field of lampshade design, paper folding method has been highly utilized as the non-flat texture by paper folding method can generate beautiful luminance distribution. Especially, if the non-flat texture is composed of curved surface units, luminance distribution in the units is continuous and visually soft. And the method combining non-flat...

The convex side of a parabolic mirror realizes to convert focusing light into parallel one. Using this feature, we propose a structure which is composed of concave and convex parabolic mirrors. This new-type structure converts parallel light into highly-dense parallel light. The structure has several interesting geometric features. This structure r...

As a result of tsunami associated with the Nankai Trough Earthquake, the predicted death toll in night-time is larger than that in day-time. That is why the start of evacuation is often delayed if an earthquake occurs at night, and the walking speed of evacuation at night tends to decline due to poor visibility caused by low illuminance level of ev...

In Japan, from long ago, paper folding method was adopted into Japanese traditional carry type lampshade, 'Chouchin', and stationary lampshade, 'Andon'. In the present, lampshades manufactured with paper folding method of a Danish lighting equipment company are also popular in not only Denmark but also other countries. All lampshades of the company...

In the previous paper, Suzuki et al. proposed a method to measure the illuminance making use of a quadcopter. Spatial illuminance of large space could be continuously measured by this method. In the paper, the PHANTOM3 (Da-Jiang Innovations Science and Technology Co., Ltd.) was mainly used for basic measurement. In contrast, the measurement in this...

Recently, computer simulation system can predict precise illuminance distribution in a space before construction of a building. However, sometimes position and angle of lighting equipment in the space may be slightly different from designed position and angle. The slight error causes unexpected dark spot if the space is very large and the dark spot...

We investigate behaviour of a new daylighting system with a convex parabolic reflector. Our new daylighting system can solve a thermal problem that many daylighting systems have. For realising this daylighting system, we derive an analytical solution of the Suzuki model that describe light not passing through a focal point. Using the 2D ray-tracing...

When a large tsunami occurs at night, greater casualties can be expected than might occur during a similar daytime event. In this study, we investigated illuminated route signs for tsunami evacuation by examining noticeability under different installation conditions. We began by installing prototype route signs in a coastal town where tsunami damag...

Lampshade was developed as wind shield for light source when fire was used for light source. Though contemporary light sources, like LED lamp, fluorescent lamp and incandescent light, are working with electricity and wind shield is not required for the light sources, almost all light sources are still covered by lampshade to arrange or control lumi...

Considering inseparability of shapes and light, authors introduced lighting equipment design in graphic science education field from 2004. On the other hand, authors also proposed luminous flux control method by curved surfaces from 2007. The luminous flux control is including daylight control and artificial light control, and as the methods of art...

Skew Quadrilateral Elastic Folding paper folding method had been proposed to construct shell structures with non-flat texture in the field of lampshade design. With the methods, final shape is constructed by skew quadrilateral unit with a curved surface. Though the shape of the curved surface in the unit has been considered as almost cylindrical su...

The historical and cultural background in Japan and Denmark is significantly different , however, they are sharing some common points in the delicate sensitivity to the light. Both people like diffusely transmitted light than dazzling and bright light, and also like a gradation of light and shadow. To make sure preference of lampshade by Danish peo...

Yoshimura pattern is one of the most typical paper folding methods in the field of lampshade design. A Yoshimura pattern is a set of skew quadrilaterals, and each is composed from two planar triangles. Lampshades manufactured with Yoshimura pattern have a nonuniform luminance distribution overall, however, the luminance distribution within a skew q...

Historically, paper folding method was adopted into Japanese traditional lampstand 'Andon' and western lampshades. If we put non-flat texture on the surface of such lampshade with paper folding method, nonuniform luminance distribution appears on the surface according to basic laws of illuminance. Yoshimura/Diamond pattern is one of the most typica...

Currently, daylighting ducts system can be mentioned as one that is widely used as a lighting device. Daylighting duct system efficiently take light from outside during the day, and brighten the room carrying the required location of the building by a duct that has a high reflectance mirror an inner surface. They are a highly efficient use of natur...

For long years, Baltic cities and Kobe city had strong relationship at administrative aspect and academic aspect. Recent several years, the relationship has been recognized again and started cooperative activities again. And there are some cooperative plans in future. In this paper, authors would like to explain history and starting/restarting chan...

Developable surfaces have significant advantage in manufacturing process, though designing of the surfaces have much restrictions. Author have already proposed combined devel-opable surface design method and introduced the method to CG exercise class of graphic science education. In this method, each developable surface which composes designed shap...

This paper introduces a generation method of developable surface by manipulation （translation, scaling and rotation） of curved line and a designing method of complicated shapes by combination of generated developable surfaces. This method enables to design complicated shape constructed by combination of cylindrical surfaces and conical surfaces. At...

In graphic science education, understanding of knowledge about shape and light is quite significant. The knowledge includes classification of shapes, function of shapes, behavior of light and anticipation of brightness distribution. CAD and 3DCG application enabled designing of complicate shapes and rendering of brightness distribution on the shape...

Developable surfaces afford certain advantages during the manufacturing procedure; similarly, tangent surfaces are also advantageous because they allow more design possibilities. We have developed a design method that uses tangent surfaces with a three-dimensional modeling tool and rapid prototyping system. First, two examples of lighting equipment...

The final goal of this research is grasping the relation between visual quality and shape of a real space. The visual quality of a real space means effects on human psychology or difficulty of evacuation. As the first step, this paper argues a description method of spatial complexity in terms of visibility. A simple concave figure can be used as an...

Manufacturing of objects with complicated curve surface had limitation in terms of both designing aspect and modeling aspect. 3-Dimensional modeler solved the limitation of designing stage. Now, rapid prototyping system is solving the limitation of modeling stage as the system can complete modeling of objects with highly complicated curve as long a...

In the garden of Ryoan-ji temple, a world heritage in Japan, 15 stones are placed and they give visitors special impression. Almost all past research about the stones arrangement were analysis of intension of the garden designer or that of rules of arrangement. This paper discussed the relationship between physical stones arrangement and psychologi...

As a serious of activities conducted by the group of Urban Study, Osaka City University, authors had been proposed plans for environment improvement and activation of Higashiyokobori-gawa river district of Osaka, Japan. This area is located under an elevated highway, resulting in an uncomfortable environment in terms of light, view, air, water and...

Manufacturing of objects with complicated curve surface had limitation in terms of both designing aspect and modeling aspect. 3-Dimensional modeler solved the limitation of designing stage. Now, rapid prototyping system is solving the limitation of modeling stage as the system can complete modeling of objects with highly complicated curve as long a...

Daylighting is highly significant from the viewpoint of energy saving and healthy life. However, considering density of housing in residential area of large cities, it is very difficult to secure sufficient daylight and lead daylight to whole space in the house. High side lighting is one of the solutions for such situation. And when high side windo...

Various crimes have been steadily increasing and many people feel uneasy about public safety. Especially, the number of snatch occurrence in Osaka prefecture has been the top in Japan for the last 32 years, and it is a serious problem. This study aims to research relationships between road spatial factors and the occurrence of snatches by quantifyi...

This study aims to know the characteristics of the road structure by quantifying the road spatial factors, from the standpoint of visibility in the road network in Kyoto city, Kobe city and Osaka city. Kyoto city has the two different road structures. One of them is the orderly grid network in the urban area, the other is the complicated network in...

Various crimes have been steadily increasing and many people feel uneasy about public safety. Especially, the number of snatch occurrence in Osaka has been the top in Japan for the last 31 years, and it is serious problem. This study aims to research relationship between visibility and occurrence of snatch by quantifying the visibility. At first, f...

The exact daylight simulation is quite difficult even now in the practical field of architectural and lighting design. The sub-working group on daylight simulation in Architectural Institute of Japan was established in 2003 to find solutions for that situation. This working group has three sections: a benchmark group, an interface development group...

Jyodoji-Jyododo, Buddhist temple located in Ono-city, Hyogo-prefecture, Japan, is well known by the light phenomenon appeared in the architecture. The architecture was built in 1197 and now authorized as Japanese national treasure. There are three statues of Amitabha-Tathagata in Jyodoji-Jyododo. The sunlight come through opening, which located bac...

The Jodo Hall of the Buddhist temple Jodo-Ji (1197, designated national treasure) was originally built by a priest Chogen on a low hill with a broad westward view in the Obe-no-sho manor area, and its frontal axis leans at an angle of approximately nine degrees from due west toward the north. Focusing on this deviation of the frontal axis, this res...

In Osaka City University, Graphic Science Education has been located not as an entrance of drawing and designing exercise but as design language education. Design language is constructed by knowledge and technique which facilitates intelligible communication making good use of figures and drawings. From academic year 2006, number of lecture units i...

In Osaka City University, Graphic Science Education has been located as design language education constructed by knowledge and technique which facilitate intelligible communication making good use of diagrams. However, the effect of light flow is not sufficiently considered comparing to shape factor though light flow also give great effect to the w...

The purpose of this research is to understand the priority of parameters which dominate three-dimensional impressions of the Stereoscopic projection with depth information. Our final goal is to propose the standardized images which enable us to various Stereoscopic projection systems. We adopted the pupil distance, the texture of surfaces and the s...

The aim of this paper is to assess earthquake hazards to human life from major active fault systems distributed across the Japanese archipelago and propose a way of evaluating grade of risk. We focus on implementation of the ranking of risk grade by presumed damage population to determine the priority order of implementing excavation studies on act...

In Osaka City University, Graphic Science Education has been located not as an entrance of drawing and designing exercise but as design language education constructed by knowledge and technique which facilitate intelligible communication making good use of diagrams. Based on the concept, Graphic Science (projection method, hand drawing skill, const...

Descriptive geometry was taught with the aim at promoting the un-derstanding of the projection method and the learning of its drawing technique. With the advancement of computer technology, which prompted the introduc-tion of computer-aided graphics processing, "graphic science" has prevailed as a term that encompasses various areas of graphics pro...

To evaluate physical quantity defined in all directions and to describe it on a two-dimensional plane, the authors proposed the use of an axisymmetric hexacosahedron, a uniform polyhedron in which 26 solid angles derived from each polygon are equal, and investigated a method of discretizing physical quantity in all directions using this polyhedron....

Recently, suggestions by local residents committee are playing significant role in community planning. However, residents cannot understand content of plans sufficiently if planning information are offered by only documents and 2-dimensional drawings. To solve these problems, visual information is considered so effective that models and photographs...

Until now, graphic science education was mostly taken as the entrance of design and drawing education in the areas of architecture and machinery en-gineering. However in a highly advanced information society like ours, there are increasing demands for skills to graphically express complicated information in an easy-to-understand manner, and graphic...

Due to recent advanced image processing technology, disaster information from satellite image data enables us to obtain various disaster information via remote sensing at anytime and place. Until this time, however, a system directly contributing to disaster management for disaster mitigation has not often been discussed. This is because much atten...

Graphic science education has been regarded as an entrance of drafting and design education in the engineering fields. However, highly advenced information society requires the ability to describe complicated information in graphical style which audience can easily comprehend summary of the information. Considering the background, Osaka City Unive...