船舶市场复苏缘何快于预期

金融危机爆发以来,船舶市场经历了一次浓缩但相对完整的船市小周期,即萧条、适度回暖、复苏。那么,两年来深处金融危机漩涡中的造船业,为何能快速摆脱衰退实现复苏?市场要素发生了哪些变化?未来船市又将如何发展呢?     

Strong bottom–up effects on phytoplankton community caused by a rainfall during spring and summer in Sagami Bay,Japan

To assess the consequences of bottom-up effects on phytoplankton community composition during the rainy season, phytoplankton levels and environmental factors were monitored daily from 12 April to 22 July 2003 in Sagami Bay, Japan. The relevant environmental factors were analyzed using cross-correlation analyses. Based on time-series analysis, low surface salinity conditions lasting 0 or 2 days after heavy rainfalls resulted in significant nutrient loading, such as dissolved inorganic nitrogen (DIN), into the coastal area. Also, Chlorophyll-a (Chl-a) concentration frequently increased 2 and 6 days after rainfall. Based on the high total Chl-a concentration, the time was divided into three periods, from 1 to 11 May (Period A), 26 May to 9 June (Period B) and 30 June to 22 July (Period C). The phytoplankton assemblages during Period A were dominated by two dinoflagellates, Ceratium furca and Ceratium fusus. Prior to these species blooming, the heterotrophic dinoflagellate Noctiluca scintillans was dominant. During Period B, the phytoplankton communities were dominated primarily by the diatoms Rhizosolenia delicatula, Hemiaulus sinensis and Navicula spp. Finally, Cerataulina dentata, Rhizosolenia spp., Lauderia borealis and Neodelphineis pelagica were dominant during Period C. After increases in phytoplankton abundance, available nitrogen (N) and phosphorous (P) were consumed and exhausted, which were considered a potential cause of the shift in the dominant organisms from large diatoms to pico- and nano-plankton in the low Chl-a environment. In particular, silicate (Si) was not a major limiting factor for phytoplankton production, since the Si:DIN and Si:P ratios clearly demonstrated that there were no any potential stoichiometric Si limitations, and almost all silicate concentrations were > 2.0 µM during this study. Our results reveal that nutrient sources supplied by river discharge are a main cue for strong bottom–up effects on algal bloom succession during the early summer season in Sagami Bay.     

地铁交通诱发邻近建筑物振动的实测与分析

根据现场实测数据,对某地铁2号线沿线典型区段地铁引起的临近建筑物振动实况和振动特性及其传播规律等进行了分析研究。结果表明:地铁诱发的沿线建筑物的振动以竖向为主,且楼层竖向振动基本表现为整体振动;在框架结构中,振动信号主要是沿柱子向上部楼层传播;楼层振动主要表现为低频的楼板振动,楼层间信号的放大主要集中在20 Hz以下的低频信号。此外,本文还给出建筑物振动实测资料的评价分析,为评估地铁运营诱发的环境振动与城市规划设计提供参考。     

永字八法

永字八法是以"永"字的八笔(点、横、竖、钩、捺、仰横、长撇、短撇)为例,阐述毛笔正楷点画用笔的一种方法.     

城市公路施工现场物资管理

为了加强施工企业市场竞争力,在施工中,对现场物资进行科学管理,对施工成本严格控制,是企业生产经营非常必要的手段之一,介绍了施工中做好现场物资管理的方法和建议.     

RBF神经网络在传感器故障诊断中的应用研究

提出一种基于RBF神经网络的传感器在线故障诊断方法,用某气囊隔振系统隔振装置中大量的传感器数据进行了仿真实验,验证了方法的可行性.通过对每个传感器建立单独的神经网络预测模型,实现多传感器的故障诊断.     

SEW行走三位一体减速机输出轴油封改造

分析了门座式起重机行走机所采用的SEW减速箱漏油现象，介绍了技术改造的方案，取得了较好的效果。     

加强施工技术管理,提高企业竞争力

施工企业的技术管理是企业管理的重要组成部分,其优劣关系到施工企业在市场经济中的生命力和竞争力。该文从施工过程、技术文件、科技进步、人员管理等几个方面介绍技术管理。     

西南某变电站场地适宜性评估研究

西南山区山高谷深,极易发生各类地质灾害。对变电站站址地质环境条件进行了详细论述,对地质灾害的类型（危岩崩塌体）、分布进行阐述,对工程建设可能引发或加剧及工程本身遭受的灾害进行了综合评估,提出了防治措施建议。     

内容中心网络系统及其在船联网中的应用

文章根据信息技术发展趋势,提出将内容中心网络与现有技术结合,建设新的船基信息网络的方法。介绍了内容中心网络的系统结构与工作原理,并以船基数据传输系统为研究对象,建立了相应仿真模型。通过分析网络的内容缓存命中率、内容服务器负载、系统传输速度与完成一次数据传输所需经过的路由跳数等性能评价指标,指出了内容中心网络相比于IP网络等现有网络的优点,并验证将该技术应用在船联网中的优势与可行性。