Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agricult...Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agriculture have a negative impact on the environment and consequently on human health. While chemical fertilizers may not have to be abandoned in agricultural production systems, limiting their use could help to make agriculture sustainable and resilient to climate change. In Senegal, the level of mineral fertilizers used in market gardening has become alarming in the Niayes area. As a result, microbial biotechnologies have been promoted for biofertilizer production of common bean (Phaseolus vulgaris L.) cultivation. Rhizobial inoculums have thus been used to reduce the rate of chemical nitrogen fertilizers being applied in cropping systems. Several investigations in the laboratory, on experimental stations and in the field have shown a possibility of a significant reduction in the use of nitrogen fertilizers in common bean production. Conventional mineral fertilization use can be reduced from over 120 kg N/ha to 20 kg N/ha. This contributes both to a very significant reduction in the application rate with the same level of yield and to an improvement in the standard of living. In addition, the environmental impact of using chemical fertilizers can be mitigated. This study is a contribution to the promotion of biofertilizers adoption in agricultural systems.展开更多
叠前偏移技术在地震数据处理中发挥着非常重要的作用。然而,利用偏移速度分析方法处理复杂地质构造时,往往难以精准重建速度模型,导致共成像点道集的同相轴发生弯曲,影响构造的成像精度。基于动态时间规整算法的地震数据叠加方法通过匹...叠前偏移技术在地震数据处理中发挥着非常重要的作用。然而,利用偏移速度分析方法处理复杂地质构造时,往往难以精准重建速度模型,导致共成像点道集的同相轴发生弯曲,影响构造的成像精度。基于动态时间规整算法的地震数据叠加方法通过匹配参考地震道与其他地震道的相似性来校正同相轴的一致性,但当各地震道之间的幅值差异较大,或者地震数据信噪比较低时,该方法易出现错误匹配的情况,进而导致波形发生畸变,因而影响了其在道集校正中的应用效果。针对上述问题,提出了一种基于迭代光滑动态时间规整算法(iterative smooth dynamic time warping,ISDTW)的共成像点道集叠加方法,该方法引入平滑约束和迭代策略对规整路径进行优化,提高了道集的校正精度和同相轴的一致性。特别是在复杂地质条件下,ISDTW算法取得了较好的成像效果。合成数据和实际数据的测试结果验证了ISDTW算法在减少局部匹配误差、提升地震成像质量方面的显著优势。展开更多
文摘Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agriculture have a negative impact on the environment and consequently on human health. While chemical fertilizers may not have to be abandoned in agricultural production systems, limiting their use could help to make agriculture sustainable and resilient to climate change. In Senegal, the level of mineral fertilizers used in market gardening has become alarming in the Niayes area. As a result, microbial biotechnologies have been promoted for biofertilizer production of common bean (Phaseolus vulgaris L.) cultivation. Rhizobial inoculums have thus been used to reduce the rate of chemical nitrogen fertilizers being applied in cropping systems. Several investigations in the laboratory, on experimental stations and in the field have shown a possibility of a significant reduction in the use of nitrogen fertilizers in common bean production. Conventional mineral fertilization use can be reduced from over 120 kg N/ha to 20 kg N/ha. This contributes both to a very significant reduction in the application rate with the same level of yield and to an improvement in the standard of living. In addition, the environmental impact of using chemical fertilizers can be mitigated. This study is a contribution to the promotion of biofertilizers adoption in agricultural systems.
文摘叠前偏移技术在地震数据处理中发挥着非常重要的作用。然而,利用偏移速度分析方法处理复杂地质构造时,往往难以精准重建速度模型,导致共成像点道集的同相轴发生弯曲,影响构造的成像精度。基于动态时间规整算法的地震数据叠加方法通过匹配参考地震道与其他地震道的相似性来校正同相轴的一致性,但当各地震道之间的幅值差异较大,或者地震数据信噪比较低时,该方法易出现错误匹配的情况,进而导致波形发生畸变,因而影响了其在道集校正中的应用效果。针对上述问题,提出了一种基于迭代光滑动态时间规整算法(iterative smooth dynamic time warping,ISDTW)的共成像点道集叠加方法,该方法引入平滑约束和迭代策略对规整路径进行优化,提高了道集的校正精度和同相轴的一致性。特别是在复杂地质条件下,ISDTW算法取得了较好的成像效果。合成数据和实际数据的测试结果验证了ISDTW算法在减少局部匹配误差、提升地震成像质量方面的显著优势。
