Many acoustical simulation methods have been studied to investigate acoustical phenomena. Modeling of the directivity pattern of a sound source is also important for obtaining realistic simulation results. However, there has been little research on this. Although there has been research on sound source identification, the results might not be in a suitable form for numerical simulation. In this paper, a method for modeling a sound source from measured data is proposed. It utilizes the sum of monopoles as the physical model, and the modeling is achieved by estimating the model parameters. The estimation method is formulated as a convex optimization problem by assuming the smoothness of a solution and the sparseness of parameters. Moreover, an algorithm based on the alternating direction method of multipliers (ADMM) for solving the problem is derived. The validity of the method is evaluated using simulated data, and the modeling result for an actual loudspeaker is shown.

Wo τking cond 拑 ons and wofkers physical sぼain in underground GQns 蜘 ctions were surveyed which were dono by caisson or shield method ，23 casos on seven sites were surveyed ． 4cases of caisson and 5 cases of shield were con − structed by compressed air conditions ， The frozen soil method -vas adopted to one shje】 d const 川 ction site ． Followings are the reSultS Of 山 e surveyes ， 1． Sound levels that could cause temporary or permanent threshold shift were recorded ． 2． Because of masking effect by noise on conversations in sitcs ， jt seems ヒ o arise the reduction of perfomance of works and dist ロrba 皿 ce ofreport in an emerger 】cy ． 3． ln underground construction sites in general ， not oniy darkness but a 】 so glare is remarkable ， and 血 ey affect on the work and fatigue by work ． 4． Large rate of increqse of puls frequency a1 work is recorded ， that is inappropriate for the longer ' duranon ofworks ． 5， The narrow working space in the underground affects workers feelings of fatigue ． 6． Fro【n the regressioll analysis between workjng tcmperaturcs and work stress ， there are a s【 rong rela 重 ion between the cumu 】 ative temperature of workers and the subjective feelings of fatigue． 1 ．緒言 1． 1研 究の 背 景

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Reinforced soil retaining walls with rigid facing are built by short reinforcements and cast-in-place concrete, and has already a number of actual construction results as railway embankments. Major limits of the construction method are: (1) the ratio of manual work is high, such as production, hand tamming and piling of gabions, and (2) the formwork of the facing requires much labor. Then, we used first an L-shaped welded wire net as a form-anchor of the formwork of the facing in place of gabions. In order to evaluate the practicality, we performed lateral pressure measuring tests at the time of placing concrete, and pull-out tests of a presupport material which used the L-shaped welded wire net. In this paper, the practical performance is examined as a form-anchor of a pre-support material based on the field tests. Consequently, it has been confirmed that a lateral pressure approximately equal to water pressure acts temporarily and partially when concrete is cast, and that a pre-support material has a pull-out resistance to withstand the lateral pressure.