Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the y...Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the yield response of two processing tomato hybrids （Ercole and Genius） grown under different irrigation treatments, a field trial was conducted during the 2008 growing season in Southern Italy. Three irrigation treatments were used： the restitution of 70% of maximum evapotranspiration （ETc） both under ＂Deficit Irrigation＂ （70DI） and ＂Partial Root-zone Drying＂ （70PRD） strategies; full irrigated （FI： 100% ETc）. The two water deficit irrigation treatments （DI and PRD） showed stomatal conductance values lower than FI treatment and saved a substantial amount of water maintaining reasonable marketable yield. Moreover, PRD strategy showed slightly higher ＂Water Use Efficiency＂ （WUE） values than DI. Finally, ＂yield response factor＂ （Ky） showed always values less than unity, indicating the possibility to adopt, within certain limited condition, both DI and PRD in field-grown processing tomato cultivated in Southern Italy. In conclusion, in our experimental conditions, deficit irrigation practices seem to be acceptable relatively to processing tomato yield aspects and Ky could be promoted as a useful indicator for irrigation in water deficit conditions.展开更多
Root of characteristic equation for cylindrical Bessel equation eigenvalue problems on general interval is of great real physical importance at engineering and physical. First, the characteristic equation of cylindric...Root of characteristic equation for cylindrical Bessel equation eigenvalue problems on general interval is of great real physical importance at engineering and physical. First, the characteristic equation of cylindrical Bessel equation eigenvalue problem on general interval is given, second, by mean of compared method, we obtaining roots of characteristic equation with Matlab program is discussed.展开更多
This paper aims to calculate Argentinean consumers＇ willingness to pay （WTP） for organic fresh chicken in the domestic market, by applying the Contingent Valuation approach and with a view to providing some useful ...This paper aims to calculate Argentinean consumers＇ willingness to pay （WTP） for organic fresh chicken in the domestic market, by applying the Contingent Valuation approach and with a view to providing some useful insights for promoting organic chicken production and consumption in Argentina. A binomial logit model was estimated using data from a consumer survey conducted in Buenos Aires City, Argentina. Willingness to pay is explained by the consumption of organic products, health risk perceptions, concerns about production processes and also regulation issues, and label reading. The WTP calculation reveals a mean value of 21.4%/kg and a median value of 19%/kg. These results indicate that organic chicken is positively valued by consumers. In fact, it provides the nutritional and product origin information that buyers require and they consider it a safer option than conventional chicken.展开更多
In the transportation service, customers＇ specially ordered time window is not always strictly obeyed and deviation of service time from customer-ordered time window determine customers＇ satisfaction degree, which c...In the transportation service, customers＇ specially ordered time window is not always strictly obeyed and deviation of service time from customer-ordered time window determine customers＇ satisfaction degree, which can be quantified by satisfactory function. And improved saving algorithm is proposed to solve the multi-objective model. A case study is also presented to verify effectiveness of the proposed algorithm.展开更多
文摘Due to the global expansion of irrigated areas and the limited availability of irrigation water, it is necessary to optimize water use in order to maximize crop yields under water deficit conditions. To evaluate the yield response of two processing tomato hybrids （Ercole and Genius） grown under different irrigation treatments, a field trial was conducted during the 2008 growing season in Southern Italy. Three irrigation treatments were used： the restitution of 70% of maximum evapotranspiration （ETc） both under ＂Deficit Irrigation＂ （70DI） and ＂Partial Root-zone Drying＂ （70PRD） strategies; full irrigated （FI： 100% ETc）. The two water deficit irrigation treatments （DI and PRD） showed stomatal conductance values lower than FI treatment and saved a substantial amount of water maintaining reasonable marketable yield. Moreover, PRD strategy showed slightly higher ＂Water Use Efficiency＂ （WUE） values than DI. Finally, ＂yield response factor＂ （Ky） showed always values less than unity, indicating the possibility to adopt, within certain limited condition, both DI and PRD in field-grown processing tomato cultivated in Southern Italy. In conclusion, in our experimental conditions, deficit irrigation practices seem to be acceptable relatively to processing tomato yield aspects and Ky could be promoted as a useful indicator for irrigation in water deficit conditions.
文摘Root of characteristic equation for cylindrical Bessel equation eigenvalue problems on general interval is of great real physical importance at engineering and physical. First, the characteristic equation of cylindrical Bessel equation eigenvalue problem on general interval is given, second, by mean of compared method, we obtaining roots of characteristic equation with Matlab program is discussed.
文摘This paper aims to calculate Argentinean consumers＇ willingness to pay （WTP） for organic fresh chicken in the domestic market, by applying the Contingent Valuation approach and with a view to providing some useful insights for promoting organic chicken production and consumption in Argentina. A binomial logit model was estimated using data from a consumer survey conducted in Buenos Aires City, Argentina. Willingness to pay is explained by the consumption of organic products, health risk perceptions, concerns about production processes and also regulation issues, and label reading. The WTP calculation reveals a mean value of 21.4%/kg and a median value of 19%/kg. These results indicate that organic chicken is positively valued by consumers. In fact, it provides the nutritional and product origin information that buyers require and they consider it a safer option than conventional chicken.
文摘In the transportation service, customers＇ specially ordered time window is not always strictly obeyed and deviation of service time from customer-ordered time window determine customers＇ satisfaction degree, which can be quantified by satisfactory function. And improved saving algorithm is proposed to solve the multi-objective model. A case study is also presented to verify effectiveness of the proposed algorithm.
