The Miyagi-Ken-Oki Earthquake on the 12th of June, 1978 causes severe disaster in Sendai and its vicinity, and it gives many lessons on safety of residential site in and around city. Destroyed houses amount more than 700, and many other structures are broken. Most of them are in the alluvial plain or in the hill-land where newly-built housing estates have rapidly expanded. While originally built-up area of Sendai on the river terrace has little disaster. The characteristics of the disaster in the alluvial plain and the hill-land are as follows,
Alluvial plain
The damages or the acceleration of the earthquake motion are closely related to the microtopography or the thickness of uppermost clayey deposits. Each topography, such as beach ridge, natural levee, back marsh etc. has certain range of the accelaration estimated by overturning of gravestones (Fig. 2). Due to strong motion, many houses are destroyed, and most of them are concentrated on the artificial ground which have been formed on back marsh or abandoned channel (Fig. 6). In addition to such subsoil condition, the damages depend on house type. Houses with big and heavy roof, such as traditional Japanese farmers' house, sustain grater damages than small houses.
Hill-land
Around Sendai, housing estates have been developed since 1960', modifying natural land form. These residential estates can be classified into three types, according to the extent and mode of modification of land form (Fig. 8). In the “A-type” housing estates, many cracks are observed along the boundary between artificial fill and cut. Damages of houses, water and gas pipes or other structures appear intensively along the cracks (Fig. 10). In the “C-type”, many cracks arise on artificial retaining walls, causing disastrous failures at places. The damage differs from estate to estate according to the above mentioned modification types, and the variance of the degree of the damages are explained by the difference in the distribution of the acceleration estimated by overturning furnitures (Fig. 12).

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The retail structure has changed with big stores opening and varying consumer behavior for last ten years, and it is the most important to study the changing retail area and the structure of shopping street, especially the vertical structure of sphopping street in the city centers where multifloored buildings are growing.
The purpose of this paper is; 1) to analyse the change of retail area with the opening of big stores, and 2) to analyse the vertical structure of nine shopping streets in Yamagata Basin.
The author analysed the change of retail area comparing the rate of shopping dependency, the rate of retail sales and the index of retail activity (I. R.), where
I.R.=(Ri/∑Ri-Pi/∑Pi)×1000
Ri: retail sales of the city i Pi: population of the city i.
The results are summarized as follows.
(1) Two remarkable tendencies are clarified in the change of Yamagata retail area; extending as to high-level goods and diminishing as to lower-level goods. The latter is due to the opening of big stores in other cities. The shopping streets in Yamagata city have inclined to high-level goods and have been distinguished from the shopping streets in other cities in function and chracter.
(2) Except big stores, the specialized stores in Yamagata central shopping streets, those are of the highest level among the above nine, are using up to the third floor of the building, and the second and third floores are apt to be used for amusement-service function.

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This study is concerned with the trend-surface analysis about the population density of Seoul city in 1977.
For the analysis, 276 hexagonal grids of which the perimers are 1km are overlapped on the study area and the central points of the hexagons are dealt with as the data points.
The conclusion is as follows:
(1) A hexagonal grid is the most rational grid than any other grids.
(2) The land use pattern is reflected on the expected population density and that is also reflected on the functional structure of the city.
(3) The distribution pattern of the expected population density is produced as the concentric zone (except 1st degree trend-surface).
(4) In the case of 6th order trend-surface analysis of Seoul city, the expected population density is consisted of the two main parts. One is the central major maximum ridge of which the core district is Myeongryun·Hyehwa·Ihwa·Samsun·Changsin-Dong, and the other is Kuro-Dong manufacturing estate district.
(5) The coefficient of determination of 6th order trend-surface analysis is 67.9%. The most significant thing is that the residuals were converted randomly. That means that the expected population density is adequated for the actual population density.
(6) The trend-surface analysis produces different consequence by the size of the testing area; to test the urban part versus the urban whole.
(7) By the 6th order trend-surface analysis of Seoul city, CBD is posited at the descending ridge of the central major expected population density mountain.
(8) In the case of Seoul city about the increment of the goodness-of-fit of the trend-surface analysis, the even-number degrees are fitted better than the odd-number degrees.

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