丁字湾潮间带日本刺沙蚕幼体对底栖微藻的摄食率

采用同位素 14 C现场同步示踪技术 ,测定了丁字湾北部泥质潮间带不同体长日本刺沙蚕幼年个体对底栖微藻的摄食率。结果表明 ,日本刺沙蚕的个体摄食率与虫体体长呈正相关 ,其总体摄食率为 0 .5 399× 10 -3 h-1,相当于摄食底栖微藻 1.985μg C· 10 cm-2 · h-1。同时得出 5月份现场条件下底质表层初级生产力为 38.2 4 μg C· 10 cm-2· h-1。     

鲁中地区铜冶店断裂带文祖断裂带两侧找矿前景

鲁中地区文祖断裂、铜冶店断裂带为同一断裂带,其两侧莱芜上游北部地区、莱芜铜山地区、新泰旋崮河地区的地质体中赋存有金、铜矿体,该断裂带具备赋存金、铜矿的有利条件,具有找金、铜矿前景。     

艾山省级地质公园地质遗迹类型及成因分析

艾山省级地质公园位于栖霞市西北部,园区内山脉总体呈NW-SE向展布,东南部的艾山与西北部的南崮、北崮遥相呼应,绵延25km,涉及松山、苏家店2镇,地理坐标跨东经120°     

大亚湾风暴潮波浪传播数学模型

本文建立了大亚湾风暴潮涌浪传播数学模型,以任意多边形离散计算海区,每一多边形构成单元,以波浪运动学和动力学守恒方程模拟单元内能量传递,以风暴潮过程模拟边界入射波高过程,用风暴潮涌浪传播基本方程和波能缓坡方程结合模拟湾口巨浪向湾内的传播过程。通过分析大亚湾不同种类岸线反射系数的概率分布,并结合实测波高对模型进行率定,最终确定模型参数。将大亚湾特征点计算波高与统计推荐波高比较进行模型验证,结果显示SE向波高与H_(13%)推荐波高对应较好,可以用于大亚湾海区的波浪预报。计算当大亚湾口分别出现10年一遇、50年一遇及100年一遇的波高时,在E、ESE以及ES向入射波浪条件下大亚湾海域极值波高的分布。分别对风暴潮涌浪在不同类型岸线的爬高以及风暴潮涌浪传播对岸线的作用力进行计算。     

Seismogenic structures of the 2006 M<Subscript>L</Subscript>4.0 Dangan Island earthquake offshore Hong Kong

The northern margin of the South China Sea, as a typical extensional continental margin, has relatively strong intraplate seismicity. Compared with the active zones of Nanao Island, Yangjiang, and Heyuan, seismicity in the Pearl River Estuary is relatively low. However, a M_L4.0 earthquake in 2006 occurred near Dangan Island (DI) offshore Hong Kong, and this site was adjacent to the source of the historical M5.8 earthquake in 1874. To reveal the seismogenic mechanism of intraplate earthquakes in DI, we systematically analyzed the structural characteristics in the source area of the 2006 DI earthquake using integrated 24-channel seismic profiles, onshore–offshore wide-angle seismic tomography, and natural earthquake parameters. We ascertained the locations of NW- and NE-trending faults in the DI sea and found that the NE-trending DI fault mainly dipped southeast at a high angle and cut through the crust with an obvious low-velocity anomaly. The NW-trending fault dipped southwest with a similar high angle. The 2006 DI earthquake was adjacent to the intersection of the NE- and NW-trending faults, which suggested that the intersection of the two faults with different strikes could provide a favorable condition for the generation and triggering of intraplate earthquakes. Crustal velocity model showed that the high-velocity anomaly was imaged in the west of DI, but a distinct entity with low-velocity anomaly in the upper crust and high-velocity anomaly in the lower crust was found in the south of DI. Both the 1874 and 2006 DI earthquakes occurred along the edge of the distinct entity. Two vertical cross-sections nearly perpendicular to the strikes of the intersecting faults revealed good spatial correlations between the 2006 DI earthquake and the low to high speed transition in the distinct entity. This result indicated that the transitional zone might be a weakly structural body that can store strain energy and release it as a brittle failure, resulting in an earthquake-prone area.     

Crustal structure revealed by a deep seismic sounding profile of Baijing-Gaoming-Jinwan in the Pearl River Delta

The Pearl River Estuary area, located in the middle part of the southern China coastal seismic belt, has long been considered a potential source of strong earthquakes above magnitude 7.0. To scientifically assess the potential strong earthquake risk in this area, a three-dimensional artificial seismic sounding experiment, consisting of a receiving array and seabed seismograph, was performed to reveal the deep crustal structure in this region. We used artificial ship-borne air-gun excitation shots as sources, and fixed and mobile stations as receivers to record seismic data from May to August 2015. This paper presents results along a line from the western side of the Pearl River Estuary to the western side of the Baijing-Gaoming-Jinwan profile. A two-dimensional velocity structure was constructed using seismic travel-time tomography. The inversion results show that the Moho depth is 27 km in the coastal area and 30 km in the northwest of the Pearl River Estuary area, indicating that the crust thins from land to sea. Two structural discontinuities and multiple low-velocity anomalies appear in the crustal section. Inside both discontinuity zones, a low-velocity layer, with a minimum velocity of 6.05 km s~(-1), exists at a depth of about 15 km, and another, with a minimum velocity of 6.37 km s~(-1), exists at a depth of about 21.5 km between the middle and lower crust. These low velocities suggest that the discontinuities may consist of partly molten material. Earthquakes with magnitudes higher than 5.0 occurred in the low-velocity layer along the profile. The deep Kaiping-Enping fault, rooted in the crust, may be one of the most important channels for deep material upwelling and is related to tectonic movement since the Cretaceous in the Pearl River Delta tectonic rift basin.     

一种模拟舰艇全磁场的二轴磁体设计

为了解决单轴磁体模拟舰船磁场的不足,提出了一种二轴磁体的模拟方法。 采用了一种同铁芯、两绕组、同轴线和不同绕制方法的二轴磁体的设计方案。 经过严格的设计计算,确定了各设计参数,同时按 10：1 的比例制作了磁体模型,并进行了模型磁场的测量实验。 最后对二轴磁体进行了总体优化设计和性能评估分析,对其他新型磁体的设计具有一定的参考价值。     

基于椭圆约束的隧道点云滤波

针对激光LiDAR在隧道监测中隧道壁点云滤波问题,通过移动测量系统获取隧道点云数据,提出采用联合RANSAC和稳健最小二乘的点云滤波方法。首先根据移动测量航迹对点云进行里程赋值和断面切片划分,获得点云断面数据;其次通过RANSAC算法对隧道进行圆模型拟合,初步滤除加大粗差点。最后通过椭圆约束的稳健最小二乘进行精细滤波,滤除和隧道壁距离较近的粗差点,获得隧道壁点云,并拟合出隧道壁断面参数。对滤波结果进行精度评定和拟合结果的稳健分析,说明滤波结果的有效性和鲁棒性。     

智慧农田害虫时空监测系统设计

传统农业虫害测报存在时间、人力成本高,准确度难以保证等问题,难以适应现代农业发展。本文在微小农业害虫自动监控装置的基础上,结合时空分析原理和卷积神经网络识别技术,提出智慧农田害虫时空监测系统方案。文章从前端、服务器端、数据库端三方面阐述设计思路。基于设计的系统,智能识别害虫种类、数目,在此基础上进行时空分析,预测可能发生虫害的地点、趋势,最终达到农田害虫时空监测的自动化和智能化的效果。     

基于实际气体状态方程的深海采样压力补偿技术

压缩气体通常用于深海压力保持采样器的压力补偿。回收的流体样品的压力和体积与预充气体高度相关。为了更好地理解高压下气体的行为,我们提出了一个新的基于压缩因子Z的实际气体状态方程,该方程是从实验数据得出的。然后基于该经验气态方程引入了样品压力和体积的理论计算方法。最后,通过采样器进行了在115MPa下的高压模拟采样实验,很好地验证了本文所提出的计算理论。