冬季積雪地域である富山県砺波市および新潟県上越市で秋播き移植栽培したタマネギ ‘ターザン’ の抽苔株率データを用い，抽苔株率推定モデルについて検討した．タマネギの花芽形成に関する温度反応を積算したVD値，または日々の温度反応と葉数との積を積算したVDLN値について，積算期間を変えて抽苔株率との近似曲線への非線形回帰における決定係数を調査した．VDについては，いずれもの場合も決定係数が低く抽苔株率を高精度に推定することはできなかった．一方，植物体の大きさを加味したVDLNの決定係数については，砺波と上越の全データを用いた場合，1月20日まで，または移植後80日間の積算で0.75以上，砺波のデータのみを用いた場合は2月20日以降または移植後120日以降までの積算で概ね0.95以上と高かった．よって，VDLNを用いるモデルの有効性が示唆された．実用的な指標として，砺波において移植後140日...

This article proposes a novel longitudinal vehicle speed estimator for snowy roads in extreme conditions (four-wheel slip) based on low-cost wheel encoders and acceleration sensor. The tire rotation factor, η, is introduced to reduce the deviation between radius manufacturer’s marked radius. Local Vehicle Speed Estimator defined eliminate estimation error. It improves slip accuracy of four-whee...

Slips and falls and associated outdoor injuries are prevalent in cold climates. The objectives of this field investigation were to describe the consequences of slips and falls on ice and snow and the associated injuries, to assess the risks of various icy and snowy surfaces, to identify design needs of footwear, and to ascertain preventive measure preferences of outdoor workers. The organizatio...

The collared lemming in the high-Arctic tundra in Greenland is preyed upon by four species of predators that show marked differences in the numbers of lemmings each consumes and in the dependence of their dynamics on lemming density. A predator prey model based on the field-estimated predator responses robustly predicts 4-year periodicity in lemming dynamics, in agreement with long-term empiric...

In aerial radiation monitoring (ARM), the air dose rate cannot be appropriately estimated under snowy conditions due to attenuation of gamma rays by the snow layer. A technique to address this issue is required for ARM to obtain enough signals for air dose rates. To develop this technique, we investigated the relationship between snow depth and ARM measurement results using ARM, laser imaging d...

The present study was conducted during a period of two years from 2001 to 2003 in trans-Himalayan region from Mustang to Dolpa region of west Nepal. The indigenous people were found to be rich in ethnoecological knowledge regarding environment and plant resources. The locals catagorised six types of ecological land patterns such as Nakri (forest land), Penhri or pangri or Thakri or dakri (land ...