• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.35-43
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• 2004

Skid resistance is an important factor that control braking distance and secure safety by preventing slipperiness between tire and pavement surface. Decrease of skid resistance at wet condition may cause fatal traffic accidents. Dirt materials such as sand and do-icings on the road surface also can be a factor for decrease skid resistance. This study makes an investigation into influence of skid resistance between varied cement concrete pavements about surface texturing method(transverse tining, longitudinal tining, exposed aggregate surface texturing method) and wearing condition of pavement surface texture(new constructed pavement's surface, wore pavement's surface) using accelerate concrete pavement wearing tester when remains of dirt material are obtained between tire and road surface on PCC pavement. As dirt material on road surface of concrete pavement, sand, calcium chloride and old oil were used with different amount of each cases.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.62-69
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• 2013

The black cutworm, Agrotis ipsilon (Hufnagel), damages various cultivated crops and it can also be a serious pest of turfgrass, especially on golf courses. Essential oils have potential as alternative control agents for insect pests. Sixteen essential oils (anise, camphor, cinnamon, citronella, clove, fennel, geranium, lavender, lemongrass, linseed, neem, peppermint, pine, thyme, turpentine and tea saponin) and paraffin oil were assessed in the laboratory, the green house and field trials for their efficacy against black cutworms in turf. Treatment of potted cores of perennial ryegrass turf with anise, cinnamon, neem, paraffin or turpentine reduced black cutworm damage in a greenhouse trial, and in a similar trial, applying neem oil at 4000, 2000 and 1000 ppm resulted in 100, 100 and 64% mortality, respectively, of black cutworms. Weight of survivors at the 1000 ppm rate was 5- fold less than weight of comparably-aged controls. Neem oil (2000 ppm) reduced growth of black cutworms feeding on treated clippings. A high rate of neem oil followed by irrigation (0.1 L of 20000 ppm neem oil with 0.9 L watering/$m^2$) was more effective than a lower concentration (1 L of 2000 ppm neem oil/$m^2$) against $2^{nd}$ and $3^{rd}$ instars in potted turf cores and field plots, respectively. However, not even the aforementioned higher rate effectively controlled $4^{th}$ instars in the field.