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关键词： Chlorophyll-a   Water column stratification   Euphotic depth   Nitrate   Frontal system   Hake fishery  

摘要： Annual cycles of phytoplankton biomass (using chlorophyll-a as a proxy) and seasonal patterns of environmental drivers were analyzed in a semi-enclosed coastal ecosystem (San Matfas Gulf, SMG, Patagonian Continental Shelf, Argentina). Monthly climatologies (2003-2014) of satellite images of chlorophyll-a (Chla-sat), sea surface temperature (SST), photosynthetically available radiation (PAR), and euphotic depth (Z(1%)) were analyzed using Principal Component Analysis (PCA). Satellite environmental variables were evaluated together with oceanographic field data (temperature, nitrate, and chlorophyll-a). Thus, this study analyzes the Chla-sat data to describe the spatio-temporal distribution of the phytoplankton biomass in the SMG and investigates its relationship with the regional environmental drivers. Two contrasting phytoplankton annual cycles characteristic of these temperate waters were distinguished. PCA discriminated the inner and outer areas separated by a complex frontal system. The gulfs inner waters showed a bimodal phytoplankton cycle (maximums in autumn and spring) associated with the seasonal stratification of the water column in deeper areas and the consequent nitrate limitation in summer. The outer waters adjacent to the continental shelf showed unimodal cycles (maximum in autumn or spring) linked to the vertical mixing of the water column in shallow areas with moderate light intensity and nitrate availability. For both annual phytoplankton cycles, light is the main limiting factor in winter. Finally, the analyzed environmental patterns suggest that a tidal front favor feeding and spawning fishery resources in the north of the gulf.

关键词： 设备管理   专业素能   强化   具现   高效管理  

摘要： 烟草行业商业企业物流中心设备管理员,主要承担入库、分拣打码、包装设备的运行维护与保养;设备分级分类评估;设备一机一档档案管理;设备备件验收、领用、登记、发放;年度维保计划的编制与实施等工作,是保障分拣任务顺利完成的重要力量.设备管理员工作的好坏将直接关系到分拣效率与质量,对企业的正常运行与持续发展起到越来越重要的作用.

关键词： 混凝土搅拌站   设备管理   维修技巧和常识  

摘要： 本文主要讲述了三个内容,第一个主要内容是混凝土搅拌站设备的构成及其工作原理.第二个主要内容是混凝土搅拌站各部件常见故障、原因和主要排除方法.第三个主要内容是几种常用的混凝土设备维修和改造小技巧.

标准号: DB1404/T 8-2021

关键词： Expatriation   migration   role of the firm   international human resource management   push and pull   systematic literature review  

摘要： Being able to compete in the global marketplace for highly skilled migrants is becoming increasingly important for economic prosperity. This study draws on neoclassical push and pull theory to investigate the state of scientific knowledge concerning the role of the firm in attracting highly skilled international migrants to individual host countries. Systematically reviewing economic analyses of migration flow drivers as well as management studies with organizational or individual perspectives, it establishes key themes and methodological patterns that shed light on the broader context in which firms and human resource management practitioners exert direct and indirect influences on migration decisions. Research has explored drivers of migration flows largely from an individual perspective, putting particular emphasis on relocation motivations and the career experiences of those who move abroad. However, we are still lacking a clear understanding of what kinds of companies attract international talent. The debate is missing a systematic framework and shows some notable theoretical gaps. Propositions for a future research agenda are discussed.

关键词： Automobile drivers  

摘要： In the past, in-vehicle head-up displays (HUDs) were used to display simple information including driving speed and the distance between cars. However, recent HUDs now display complex information such as advanced driver assistance information. This study aims to identify the effects of visual enhancements for HUDs on the driver's performance and workload. Twenty participants conducted the tracking tasks for information search while driving in an automotive simulator environment. The participants experienced three levels of visual enhancements (none, shaded reference bar, translucent reference bar) for each task difficulty (low, medium, high). The results showed that visual enhancements and task difficulties had a significant effect on the tracking errors and subjective workloads. These findings verify that the translucent reference bar significantly improved the tracking performance. Furthermore, the visual enhancement cues on the HUDs play an important role in visual search. This research provides practical guidelines to ensure road safety through minimizing cognitive workload on drivers. Therefore, the results will encourage interface designers to consider the visual enhancement for HUDs from a user-centered perspective.

关键词： beta-diversity   parasite macroecology   temperature   precipitation   climate   spatial distance  

摘要： A robust understanding of what drives parasite beta-diversity is an essential step towards explaining what limits pathogens' geographical spread. We used a novel global dataset (latitude -39.8 to 61.05 and longitude -117.84 to 151.49) on helminths of anurans to investigate how the relative roles of climate, host composition and spatial distance to parasite beta-diversity vary with spatial scale (global, Nearctic and Neotropical), parasite group (nematodes and trematodes) and host taxonomic subset (family). We found that spatial distance is the most important driver of parasite beta-diversity at the global scale. Additionally, we showed that the relative effects of climate concerning distance increase at the regional scale when compared with the global scale and that trematodes are generally more responsive to climate than nematodes. Unlike previous studies done at the regional scale, we did not find an effect of host composition on parasite beta-diversity. Our study presents a new contribution to parasite macroecological theory, evidencing spatial and taxonomic contingencies of parasite beta-diversity patterns, which are related to the zoogeographical realm and host taxonomic subset, respectively. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.

关键词： 安全生产管理系统   地质勘探   机电设备管理  

摘要： 矿产行业在国家发展中占据着重要位置,可以提升国家整体经济实力,为人们提供更高质量的生活水准。在矿产行业中地质勘探工作是行业的重要组成部分之一,可保证矿产资源顺利开采出来。但在实际的工作中,存在大量的安全隐患,给相关工作人员带来严重的安全威胁。本文以安全生产管理系统在地质勘探机电设备管理中的运用开始分析,并提出以下几点作为参考。