Since the mid-1950's, construction of multi-storied buildings has remarkably in creased in Japanese cities, especially in their urban cores. But there are few articles on the use of space regarding to the aspect. In this paper, the author tries to discuss on the use of mufti-floored space in connection with the growth of CBI and the construction of under-ground shopping centers, taking as example the city of Nagoya, the third largest city in Japan.
The results obtained are summarized as follows (1) In the Edo era (1603_??_1867), the main axes of CBD in Nagoya were the street of Tenmacho stretching from east to west and the street of Honmachi from north to south. But in the middle of the Meiji era (1898), with the introduction of tramcar on the streets of Hirokoji and Minami-Otsu at the fringe of the old castle town, the axes of CBD moved to these areas. Since the mid-1950's, the new CBI including Hirokoji and Ekimae (front area of the Nagoya railway station) has developed owing to the construction of many high buildings, underground shopping centers and subways.
(2) Use of multi-floored space first appeared in the urban core before the Second World War. In the 1960's it spread to the urban fringe and suburbs, while utilization of space in the urban core became more intensive. In other words, small high buildings were demoli-shed and were replaced by large buildings in the course of urban renewal.
(3) The use of multi-floored space reflects differential value of land in the CBD. In case of Sakae area land value decreases gradually from core to fringe, while in case of the front area of Nagoya station, land value of fringe declines very abruptly in comparison with that of central portion.
(4) The use of multi-floored space in the urban core was stimulated by construction of subways and the improvement of road system by the municipal authorities. As a result, underground shopping centers were developed to avoid heavy traffic on roads. It seems that development of underground shopping centers is one of the basic characteristics of the CBD of Japanese cities.
(5) Certain vertical differentiation of urban function can be seen in the urban core in connection with the multi-floored space use as shown in Fig. 8. For example, retail and amusement functions are mainly located in the first basement (B.lF) and the ground floor of high buildings which are combined with underground shopping centers and subways. Parking spaces and store-spaces are located in the second basement and the third basement, in contrast with business and dwelling functions carried on the second floor and above.

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The purpose of this paper is to study the 1957 epidemic of Asian influenza in Nagoya and its environs as viewed a spatial diffusion process. The study area is Aichi prefecture and Gifu prefecture except Hida area, the core portion being Nagoya metropolitan area. The epidemic in each city was identified from the first closing date of a class or a school caused by the influenza mass outbreaks in the elementary school and the junior high school.
The influenza breaks out in 103 cities out of 192, and the epidemic period (from May 24th to July 17th) is about nine weeks. According to the time lag of five sub-divided epidemic periods in each city the influenza tends to spread from the densely populated plain area to the mountain area, and an explanation that the outbreak pattern has been produced by the hierarchy effect (Fig. 4) and neighbourhood effect seems to be possible.
Then in order to examine the outbreak pattern from the aspect of process, the author com-pared the actual outbreak pattern with the outbreak patterns simulated by random process model and interurban diffusion model (Model I and II) by the aid of the Monte Carlo technique. Firstly, with A. D. Sorensen's coefficient of spatial association which is a kind of the nearest neighbour method, the output of random process model was compared with the actual. The coefficients of spatial association of the period II_??_V were 0.18, 0.19, 0.28, 0.33 respectively, and consequently there is a low possibility that the epidemic is resulted from random process. In addition as the outbreak in the period I is given for the model, both random process model and Model I and II, the simulation of the outbreak in the period I is not possible.
Secondly the author considered the outbreak pattern with Model I having the following main operating rules ;
1) It is assumed that the epidemic spreads from Nagoya, Kasugai, Seki and Tsukechi where the influenza broke out in the period I.
2) Muge and Utsumi where the influenza was introduced from the other regions are given for the model, and inserted in the generation corresponding to the actual outbreak period.
3) The probability of the contact of a city is determined by the contact field based on the number of commuters and externs which seems to fit the gravity model.
4) The generating frequency of the contact of the infected city is one time in one generation.
5) The city which has received the contact breaks out the influenza immediately, and continues to transmit the contact to the other cities from the next generation.
Fig. 6 is the output simulated by Model I. Though the author supposed that Model I contained the hierarchy effect and the neighbourhood effect, the neighbourhood effect emerges strongly in the simulated output compared with the actual. The coefficients of spatial association of the period II_??_V were 0.31, 0.28, 0.44 and 0.47 respectively.
Further the author attempted the simulation by Model II which is a revision of Model I in two operating rules; firstly by changing the generating frequency of the contact in proportion to the city size; and secondly by containing the density effect together with by increasing the hierarchy effect. Especially the reason why the second alternation is made needs a comment. From epidemiology it is said that the epidemic of the infectious disease is caused by the infectious chance and the susceptibility. In Model I the former is expressed by the contact field, but the latter is not considered. Calculating the coefficients of corre-lation between the outbreak date and five variables which seem to indicate the suscepti-bility, the author judged two varibales relating to the density the population density and the number of students per class in the elementary school to be comparatively signi-ficant.

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In this report the author intends to present one of the case studies on the geomorphic development of the Uetsu folded zone—the western half of Northeast Japan, where crustal movements have been active since the early Miocene and the folded Neogene strata are widely distributed. The area surveyed is located at a marginal part of the depositional basin of the Uonuma group upper Pliocene_??_lower Pleistocene which is composed of littoral and fluvial deposits. Landforms of this area are therefore supposed to have been developed throughout the Quaternary period under the distinctive influences of crustal movements.
After the deposition of the Uonuma group the folded structures were developed in some extent. Then a rather large fan was formed over the area covering two drainage basins of the Igarashi River and the Kariyada River. This is concluded from the distribution of the fanglomerate (Odaira formation) and the fact that the gravels transported by the Kariyada River are contained among the fanglomerate now located in the drainage basin of the Igarashi River. The Odaira formation is for the most part 20_??_30m in thickness and is underlain by the folded Uonuma group or the older strata. The summit level of the hills where the Odaira formation is distributed indicates the tectonically deformed fan surface (Fig. 3).
After the deposition of the Odaira formation the area concerned has kept upheaving and the main rivers have eroded by 50_??_200m downward. Many levels of terraces were formed during the dissection. They are classified into 6 levels (Ig-I_??_Ig-IV) as shown in Fig. 2. Most of these terraces are strath terraces, but some exceptions can be found. Fig. 4 shows longitudinal profiles of the terrace surfaces along the Igarashi River. It is clearly shown that the terrace surfaces converge toward a syncline between Ogibori and Sasaoka (A). The terrace deposits are thicker near the syncline than at the other localities. This indicates that the crustal movement which is recognized from the structure of strata older than the Odaira formation is of the same tendency as what is recognized from the deformation of terrace surfaces. It is also shown in Fig. 4 that terrace surfaces have been deformed by faults or flexures near Shimoppara (B, C), but this is not geologically confirmed.

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It was noted about some rivers in Japan that a valley in the upper reach of a river has a more gentle slope than has an alluvial fan in the lower reach. A simple possible hypothesis was provided for explanation by the authors. The gentle slope in the upper reach may be due to narrow width of flood water restricted by valley walls (Fig. 1).
The slope of a “flood plain” and water surface, width of water surface and velocity of flow under equilibrium condition were studied experimentally by use of a laboratory flume. Uniform and noncohensive sand, O.5_??_1.0mm in diameter was used for the experiment. The amount of sand supply and water discharge were kept constant during the operation. Six runs were carried out for different flume widths. Introduction of the water discharge and sand supply was accompanied by deposition until an equilibrium channel and a “flood plain” were established. By definition a stable equilibrium existed when the ratio of sand discharge to sand supply became to 1.0 averaged for sufficiently long time.
The flume width determined the slope of running water when the flume was narrow. When the flume was sufficiently wide as compared with water discharge, the steeper “flood plain” appeared in the flume. In the latter case, the slope of the “flood plain” and running water was determined mainly by discharge, independently of flume width (Fig. 2). It is thus inferred that there is a critical value of flume width, beyond which the slope is determined only by discharge. This value is mainly a function of discharge. The result obtained by the experiment (Table 1, Fig. 2) seems to support the above hypothesis on the slope of river bed.

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