中川 誠司

We conducted laboratory studies on the geophysical signals from Arctic saline permafrost soils to help understand the physical and mechanical processes during freeze-thaw cycles. Our results revealed low electrical resistivity (<20 Omega m) and elastic moduli (7.7 GPa for Young's modulus and 2.9 GPa for shear modulus) at temperatures down to similar to-10 degrees C, indicating the presence of a significant amount of unfrozen saline water under the current field conditions. The spectral induced polarization signal showed a systematic shift during the freezing process, affected by concurrent changes of temperature, salinity, and ice formation. An anomalous induced polarization response was first observed during the transient period of supercooling and the onset of ice nucleation. Seismic measurements showed a characteristic maximal attenuation at the temperatures immediately below the freezing point, followed by a decrease with decreasing temperature. The calculated elastic moduli showed a non-hysteric response during the freeze - thaw cycle, which was different from the concurrently measured electrical resistivity response where a differential resistivity signal is observed depending on whether the soil is experiencing freezing or thawing. The differential electrical resistivity signal presents challenges for unfrozen water content estimation based on Archie's law. Using an improved formulation of Archie's law with a variable cementation exponent, the unfrozen water content estimation showed a large variation depending on the choice of the resistivity data during either a freezing or thawing cycle. Combining the electrical and seismic results, we suggest that, rather than a large hysteresis in the actual unfrozen water content, the shift of the resistivity response may reflect the changes of the distribution pattern of the unfrozen water (or ice) in the soil matrix during repeated freeze and thaw processes. Collectively, our results provide an improved petrophysical understanding of the physical and mechanical properties of saline permafrost during freeze - thaw transitions, and suggest that large uncertainty may exist when estimating the unfrozen water content using electrical resistivity data. Published by Elsevier B.V.

楽曲と騒音の分離が困難な場合,騒音に対して適用したANCが楽曲にも影響を与えることがある.ANCが楽曲の聴感印象に及ぼす影響を主観評価によって検討し,刺激音の物理特性との相関を観察した.スペクトル重心の異なる3種類の楽曲にANCアルゴリズムを適用し,刺激音を作成した（スペクトル重心：楽曲1：620Hz,楽曲2：1099Hz,楽曲3：2061Hz）.スペクトル重心が最も低く500Hz以下に強いパワーを有する楽曲1では,好ましさの相対尺度値とSNRについての正の相関がみられた（r=0.94 p<0.05）.好ましさの相対尺度値と音圧レベルについて,優位な相関は見られなかったものの,楽曲1と楽曲2,3で異なった傾向が見られた

This study was performed to determine significant light wavelengths to improve color discrimination ability of subjects with deutan. We conducted both the Ishihara test and the Farnsworth Panel D-15 test for subjects with deutan and normal color vision. Seven different LED lights from 450 to 660 nm and an additional D65 white lamp were utilized to change the lighting conditions, including the wavelength and intensity. The results of the Ishihara test and D-15 test showed that color identification of deutans was markedly improved with the longer wavelength LEDs regardless of the intensity of the additional D65 lamp. Notably, the error rates of deutans in the Ishihara test were < 25% for LED wavelengths of 630 and 660nm. In the case of subjects with normal color vision, the D65 lamp abolished the errors in the Ishihara test, regardless of the LED wavelength. Addition of the D65 lamp also decreased the number of crossings in the D-15 test. These results suggested that illumination by LED light with longer wavelengths, such as 630 and 660nm, may provide deutans with greater red-green discrimination ability in both the Ishihara test and the Farnsworth Panel D-15 test. (C) 2016 Wiley Periodicals, Inc.

<p>近年，脳活動計測に基づく印象評価の方法が提案されており，脳活動指標を用いた印象評価は心理的バイアスの低減や，意識下の印象をも評価できる可能性が期待されている．本稿では，エアコン音の涼しさ，および好ましさといった聴感印象を対象として，エアコン音聴取時の脳活動からそれらの印象を予測するモデルを構築した．まず，刺激音としてエアコン音に時間変動を付与した刺激音を複数作成し，これらの刺激音聴取時の脳磁界を計測した．被験者には刺激音を2つずつ対にして呈示し，刺激対に対する涼しさ，および好ましさの比較判断も同時に記録した．次に，計測された脳磁界から時間-周波数特徴を抽出した後，非負値テンソル因子分解を用いて脳領域，時間ごとの周波数律動を表現する低次元の脳活動特徴量を抽出した．脳活動特徴量と刺激対に対する比較判断から，エアコン音の涼しさ，および好ましさの尺度値を予測するモデルを，回帰モデルおよびサポートベクターマシン（SVM）に基づくモデルを用いて，被験者ごとに構築した．構築したモデルの性能を一対比較判断予測の正解率によって評価した結果，SVMに基づくモデルのほうが回帰モデルよりも高い予測精度を示し，このモデルが予測モデルを用いた脳活動からの聴感印象の予測に有用であることが示された．</p>

&lt;p&gt;The influence of Active Noise Control (ANC) on auditory impression for listening to music other than noise was observed by psychometric measurement and Magnetoencephalography (MEG) measurement in a situation where both noise and sound off-target sounds were mixed. For the stimulus sound, five situations under kinds of sounds, with or without one before noise reduction and one with noise reduction by ANC, were set created for three kinds of each music. In the psychological measurement, the effectiveness adverse effect of ANC was observed in the case of music with the lowest spectral center of gravity. In the MEG measurement, the effective duration of the ACF, τe , of MEG in the 20-50 Hz range, was employed represents and it lengthened for preference stimuli.&lt;/p&gt;

<p>自動車空調音のサウンドデザインにおいては，騒音レベルの低減に主眼が置かれてきた．しかしながら，動作音が小さすぎると，機器の操作性や動作状態の了解性が低下するなどの問題が生じる場合がある．空調音の温冷感に着目し，スペクトル包絡を伸縮させた自動車空調モデル音に対する涼しさ感・暖かさ感を評価した．線形予測符号化を用いてモデル化した空調音のスペクトル重心を操作して，5種類の刺激音を作成した．それらの涼しさ/暖かさに関する聴感印象を，3種類の室温環境下でScheffeの一対比較法を用いて実施した．多くの被験者で，すべての熱環境条件において，スペクトル重心の高い刺激ほど，より涼しい印象を，逆にスペクトル重心の低いほどより暖かい印象を受けていることが示された．この結果は，暖色や寒色のような色によってもたらされる温冷印象[に似た現象であることを改めて示唆するものである．</p>

Noise induced by a heating, ventilation and air conditioning (HVAC) system in a vehicle is an important factor that affects the comfort of the interior of a car cabin. Much effort has been devoted to reduce noise levels, however, there is a need for a new sound design that addresses the noise problem from a different point of view. In this study, focusing on the auditory impression of automotive HVAC noise concerning coolness and warmness, psychoacoustical listening tests were performed using a paired comparison technique under various conditions of room temperature. Five stimuli were synthesized by stretching the spectral envelopes of recorded automotive HVAC noise to assess the effect of the spectral centroid, and were presented to normal-hearing subjects. Results show that the spectral centroid significantly affects the auditory impression concerning coolness and warmness; a higher spectral centroid induces a cooler auditory impression regardless of the room temperature.

© 2017 Institute of Noise Control Engineering. All rights reserved. Noise induced by a heating, ventilation and air conditioning (HVAC) system in a vehicle is an important factor that affects the comfort of the interior of a car cabin. Much effort has been devoted to reduce noise levels, however, there is a need for a new sound design that addresses the noise problem from a different point of view. In this study, two subjective assessments were performed focusing on the auditory impression of automotive HVAC noise concerning coolness and warmness. First, paired comparison tests were carried out under various conditions of room temperature. Five stimuli were synthesized by stretching the spectral envelopes of recorded automotive HVAC noise to assess the effect of the spectral centroid. Normal-hearing subjects were asked to rate the auditory impression of the stimuli for each pair on a seven-point scale according to how much the latter is warmer (for the winter tests) or cooler (for the summer tests) than the former. Results show that the spectral centroid significantly affects the auditory impression concerning coolness and warmness; a higher spectral centroid induces a cooler auditory impression regardless of the room temperature. Second, effects of HVAC noises on the subjects&#039; sensation of coolness and warmness were evaluated by using a method of continuous judgment by category. Room temperature were controlled to increase/decrease linearly, and HVAC noise, having warm/cool auditory impressions, were presented. Subjects had to answer their sensation of coolness/warmness at regular time intervals. Results obtained that HVAC noise has some significant effect on the sensation of coolness/warmness.