We did the hearing survey to representative of the town block association in Chiyoda Ward, Tokyo. Having clarified it is two points. 1) The activity realities as town block association. 2) Progress degree and consideration for disaster measures. As a result, the realities of a local community became clear.

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Primary communication in lecture rooms comes in the form of speech and listening. A large number of studies examining room acoustics of lecture room for the listener as they affect speech intelligibility have been conducted. However, studies focusing on the point of view of the speaker are lacking. The purpose of this study was to propose a subjective measurement of “speaking difficulty” for a speaker and investigate the relationship between the reflected sound parameters of the rooms and the evaluation of the speaker’s “speaking difficulty”. Subjective judgement tests were conducted in simulated stage sound fields and in several actual lecture rooms. Results of the tests on the degree of speaking difficulty in simulated stage sound fields suggested that reflected sound involving a single echo with more than 50-75 ms delay can cause an echo disturbance for a speaker. The same judgement tests in actual lecture rooms indicated that speakers automatically adjust their voice levels and rates of speech for verbal communication when hearing reflected sounds of self-feedback speech. However, within a certain range of vocal levels, the degree of speaking difficulty tends to be strongly affected by reflected sound. Both the placement of acoustic absorption materials in the room and the spatial balance of reflected sound influence the speaker’s evaluation of speaking difficulty.

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Ogatsu area is the east part of Ishinomaki city in Miyagi prefecture. Fifteen small fishing villages were destroyed by the tsunami caused by the Great East Japan Earthquake on March 11, 2011. We have supported to make plans of higher grounds in the position of the architectural planner considering the traditional way of life, housing, and the neighborhood community. We have cooperated with the Ishinomaki City Ogatsu General branch for four years. This paper shows the systems, divisions of roles and methods of the academic-government cooperation about the making plans of higher grounds in Ogatsu. And it verifies the challenges appeared from one side of that cooperation in earthquake reconstruction.

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This study proposed a large floating base to utilize several kinds of marine renewable energy at the same time. The paper describes a concept of the floating base on which wave energy convertors (WECs) are installed and component technologies to realize the concept. An oscillating water column type was applied to WECs. Power take-off (PTO) performance and motion characteristics of the floating base were predicted within linear assumption. A marine turbine is also investigated concretely, which is a pitch-controllable vertical axis marine turbine. From the sea tests of the floating type VAMT, availability of a pitch-controllable system is shown. In addition, component technologies to control an electrical generator for the turbine are discussed in the paper. Besides, ROV development to maintain marine structures is introduced briefly. The paper summarizes several studies to realize the floating base and shows fundamental items to develop a hybrid systems of marine renewable energy utilization.

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