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1.
龙溪口航电枢纽的建设切断了原有河道鱼类迁徙通道。为保证枢纽上下游生态连通性,基于物理学、生态学原理布置仿自然生态鱼道,为河道鱼类提供良好的回溯通道。龙溪口航电枢纽工程仿自然生态鱼道具有超长、多弯折、藕节开挖难度大、施工强度高、工期紧等多个难点,鉴于仿自然生态鱼道水流控制、鱼类回溯水生态环境模拟要求高,通过模拟天然河床实况开挖、多种测量设备精准控制开挖体形、布置拟生态深潭休息室,创新应用喷混一体化、浆砌石砌筑一体化等多种新型施工工艺,提高鱼道施工精度及效率,为鱼类迁徙创造良好的水流环境,促进岷江流域生态环境循环稳定。  相似文献   

2.
龙溪口航电枢纽工程具有点多、面广、施工难度大、各专业协同要求高的特点。当前航电枢纽工程建设管理系统尚未集成施工进度、质量、安全和通航安全问题分析功能,存在建设管理单一化、智能化水平低等问题。基于物联网、移动互联网、人工智能、可视化等新一代感知与分析技术,以数据融合驱动为主要推手,通过B/S+C/S双架构开发一套航电枢纽工程智能指挥平台。依托龙溪口航电枢纽工程,通过对施工多阶段、全过程的施工生产与航运数据的高效集成及智能指挥平台的可视化智能分析,构建航电枢纽工程智能建设指挥体系,实现对航电枢纽工程建设进度、质量、安全和通航的综合管理。信息的跨平台高效、流畅交互查询和智能分析展示,有效提升了航电枢纽工程建造的智能化水平。  相似文献   

3.
针对传统防护区运行安全管理以人工为主、信息利用低、动态评估预警缺失等问题,结合龙溪口航电枢纽防护区运行安全管理的主要问题和需求,以创新运行管理模式、强化信息互联共享、提升智能管控水平为目标,构建集数据在线辨识、涝情监控预测、安全实时诊断、风险动态评估、预警响应决策于一体的多层次系统结构,提出涝情实时监控、涝情风险评估、防洪堤安全分析与风险评估等核心功能模块的实现路径和技术要求。研究成果可为全面提升龙溪口航电枢纽防护区防灾减灾能力和安全保障水平提供技术支撑。  相似文献   

4.
为确定龙溪口航电枢纽左岸仿生态鱼道的进鱼口布置方案,结合枢纽的运行工况和现有地形条件,发现较多工况下鱼道进口附近水流条件不满足鱼类上溯要求,需采取一定的工程优化措施。针对龙溪口枢纽的特点,选取典型工况对进鱼口及枢纽下游的水流条件进行研究。根据二维数值仿真模型的研究成果,拟采用拆除电站与泄水闸之间部分纵向围堰、电站尾水坎下游开挖疏浚以及左岸生境重构等方式,优化鱼道进口水流条件。对比分析不同进鱼口布置方案的优劣,推荐采用生境重构结合开挖疏浚的综合措施,优化龙溪口鱼道进口及下游流场,两者均满足龙溪口鱼道进口的流速要求。相关成果可为类似进口水流条件的数值模拟及进鱼口布置提供技术参考。  相似文献   

5.
王虎  符业晓  徐洋 《水运工程》2023,(10):94-98
针对钢筋混凝土排架结构与附属设备安装联合施工时出现的精度控制差、质量难以保障的问题,依托龙溪口航电枢纽工程泄洪闸启闭机房钢筋混凝土排架结构工程,进行了钢筋混凝土排架结构施工工艺标准化和施工质量控制要点的研究。通过优化施工组织、施工工艺,提出工期、质量优化措施,明确排架结构施工过程中支架搭设和模板组装为主要控制要点,为同类航电枢纽工程中的排架结构应用提供参考。  相似文献   

6.
张浩  代礼红  吕刚  徐红 《水运工程》2023,(10):158-163
针对龙溪口航电枢纽工程施工期所在河段不断航,且来往船舶多,临时航道通航环境复杂的情况,设计开发了施工期智能航道系统,该系统以电子航道图为显示基础,实现航道水位、流速流量和水深的实时监测、航标遥控遥测、船舶动态管理等功能,并提供共享与服务接口,系统的实施实现了对河道表面流速场的非接触、无人值守的实时测量,以及对航标、船舶的动态管理,提高了管理效率,保障了龙溪口枢纽工程施工期工程河段的通航安全。  相似文献   

7.
针对龙溪口航电枢纽工程施工明渠临时通航问题,基于数学模型及实船试验,研究施工明渠局部疏浚淤积后船舶临时通航的水流条件及船舶试航情况。数学模型模拟了施工明渠局部清淤形成的临时航道的水深及流速,均满足船舶安全航行要求。不同吨级船舶装载及空载条件下,试验的实船可安全上下行通过龙溪口施工明渠临时航道,为枢纽建设过程临时航道通航范围及尺度的确定提供依据。  相似文献   

8.
龙溪口航电枢纽工程的主要开发任务为畅通岷江航运通道,船闸作为该枢纽的唯一航运设施,是岷江通道畅通中的重要一环,故输水系统作为该船闸核心的组成部分,其重要性不言而喻。针对该船闸输水规模较大、水力指标要求较高的问题,对船闸进行水力学计算分析以及单体物理模型试验研究。结果表明,龙溪口航电枢纽船闸输水系统设计采用闸墙长廊道侧支孔输水形式是合理的,满足设计规范要求;闸室灌泄水时水流条件及阀门开启方式满足船舶安全通行需要。  相似文献   

9.
在水利工程建设中,航电枢纽的布置、建筑物的设计和优化对枢纽的经济效益有较大影响。而这些因素又对施工期间船只的正常通航、施工导流的布置情况有比较大的影响。基于此,本文以龙溪口航电工程为例,对航电枢纽布置以及建筑物的设计进行探讨。  相似文献   

10.
为确定岷江航电龙溪口枢纽仿自然鱼道布置的合理性和设计基本参数,对工程河段开展鱼类资源调查和游泳能力测试。通过三维数值模拟计算验证鱼道池室尺寸与池室内流速关系,通过物理模型试验对鱼道内部水流流态、控制断面流速等水力学参数进行研究。提出仿自然鱼道设计方案:1)鱼道进口布置在发电厂房尾水渠末端,采用发电尾水诱鱼并在进口布设补水设施;2)鱼道采用藕节形+梯形断面结构,内设横隔,鱼道和横隔均采用天然卵石堆砌;3)下游河道左岸布设缓流平台,消除鱼类上溯流速屏障。试验结果表明,龙溪口仿自然鱼道池室内部流态多样性,流速满足过鱼要求。  相似文献   

11.
浙江内河、湖泊“负干舷”活鱼运输船航态特殊,不能按照现行船舶检验规范进行常规检验衡准,对其稳性、载重线及构造等进行了相关分析后,对检验标准提出补充建议。  相似文献   

12.
The small pelagic fish represents the link between nekton and demersal communities, and they are an important food source for some demersal fish species. In the autumns between 1993 and 2002, 74,869 stomach contents of 25 demersal fish species were analysed during the scientific surveys organized by the Instituto Español de Oceanografía. These species represent the demersal fish community of the southern Bay of Biscay. An important part of their diet (39% by volume) was composed of pelagic fish species (e.g. Engraulis encrasicolus, Gadiculus argenteus, Micromesistius poutassou, Trachurus trachurus, Sardina pilchardus, Scomber scombrus). Among all these prey species, the relevance of M. poutassou and G. argenteus stood out because of their high abundance both in the diets and during the scientific surveys. The relevance of pelagic fish as prey increased with predator size, reaching more than 60% of the diet by volume in the length range 25–29 cm. However, fish predators larger than 50 cm depended less on pelagic fish (33%), since they were also able to feed on other sources such as megafaunal invertebrates, mainly cephalopods. The pelagic fish resource was primarily exploited by 12 demersal fish species, with Merluccius merluccius and Zeus faber being the main ones feeding on small pelagics, which was related to the vertical movement of predators and prey through the water column. Survey abundance indices were used as indicators of prey abundance in the ecosystem, both for biomass and number. There was evidence for density-dependant feeding by predators on E. encrasicolus, G. argenteus and T. trachurus, while the main discrepancies between abundance in the stomachs and in the surveys were due to differential availability of prey length classes in the environment. Small prey species and individuals were exploited by most demersal fish while large prey species were less accessible to predators.  相似文献   

13.
研究机器鱼是为了模仿鱼类的游动方式,研究出更为高效、灵活的水下航行器。文中介绍了一种基于拉线机构的机器鱼,主要介绍了对拉线机构应用在机器鱼推进上的仿真分析和控制。对拉线机构的鱼尾进行了仿真分析,并对比真实鱼类游动时的体干波曲线。仿真结果显示:基于拉线机构的机器鱼与传统的多关节串联驱动的机器鱼相比能更好地模拟真实鱼类的游动。制作了机器鱼样机和控制系统,用于进一步分析研究基于拉线机构的机器鱼的性能。  相似文献   

14.
鱼类游动具有低阻高效、高机动性等特点,对鱼类的仿生学研究将为新型水下航行体的设计研制提供重要借鉴与启迪.本文综述了鱼类游动机理的研究成果,总结了国内外在水下仿生航行体方面的研究进展,分析了SMA材料性质及应用现状,提出了一种基于SMA驱动的仿鲹科鱼类波动推进的水下仿生航行体原理构型方案,可作为下一步详细设计的基础.  相似文献   

15.
针对水下传感器网络随机部署时节点分布不均匀、网络覆盖率不高问题,提出一种基于改进全局人工鱼群算法的网络覆盖优化算法。优化算法以覆盖率为目标函数自适应调整人工鱼移动步长,同时在向最优人工鱼靠拢过程中引入权重系数,提高算法寻优精度和收敛速度。实验结果表明,与遗传算法和鱼群算法相比较,该改进算法优化了网络覆盖率,加快了算法收敛速度,提升了网络性能。  相似文献   

16.
The Mediterranean ichthyofauna is composed of 652 species belonging to 405 genera and 117 families. Among these, 182 were studied for their parasitic copepods. The analysis of all the works conducted on these crustacea yielded 226 species distributed in 88 genera and 20 families. For each fish species we have established a file providing the species name of the fish, its family, its geographical distribution within the Mediterranean and some of its bio-ecological characteristics. Within each file, all the parasitic copepod species reported on each host species were listed. This allowed to know the species richness (SR) of these hosts. We thus produced 182 files within which 226 copepod species are distributed. A program was created under the Hypercard software, in order to analyse our data. Two parameters were studied. The first one is the mean species richness (MSR), which corresponds to the mean of the different SR found on the different host species. The second is the parasite–host ratio (P/H), which is the ratio of the number of copepod species by the number of host species. These parameters are calculated by our program for all the 182 species of Mediterranean fishes retained in our investigation, on the first hand, and, on the second hand, for one particular group of fish species. We used the following variables to investigate their correlations with copepod species richness: taxonomy—fish families, genera and species; biometry—maximal size of the adult fish; eco-ethology—mode of life (benthic, pelagic or nectonic), displacements (sedentary, migratory with environmental change, or migratory without environmental change), behaviour (solitary or gregarious). Other variables (colour, food, reproduction, abundance, distribution area) were also analysed but did not reveal any clear correlation. Providing that our study does not rely on quantitative (prevalence, intensity) but qualitative basis our aim was only to reveal some tendencies. These tendencies are as follows: (1) In many cases, parasite and host phylogeny seem to play an important role. There are fish families with copepods and families with few species of these parasites. The phyletic constraints could be due to the morphological characteristics of the habitat (e.g. structure of the gills) or biological/ecological characteristics that we were unable to identify. (2) It appears that the presence in a same environment of related fish species (e.g. several species of the same genus, or numerous genera of the same family) is correlated with high parasite richness. A likely explanation is that such situations favours alternated processes of lateral transfers and speciation. (3) Some eco-ethological criteria seem to favour the establishment of a large parasite species richness. It should be noted for instance that Mediterranean fishes the most often infected with copepods are generally nectonic or pelagic, migratory, and gregarious species.  相似文献   

17.
Fisheries management has been used to address declining fisheries and threats to livelihood and food security. Past research suggests that public support for fishery policies is a necessary component for sustaining the long-term success of fisheries management. This study predicted public support by examining fishers’ perspectives on co-management and fish catch since the establishment of marine protected areas (MPAs), a commonly employed fisheries management tool. Data were obtained from onsite surveys (n = 505) with fishers from three municipalities in Cebu, Philippines: Oslob, Santander, and Samboan. Structural path analyses revealed that beliefs about co-management and fish catch predicted support for fishery policies (R2 = 59%). Separate path analyses for each municipality showed that co-management had greater influence in predicting public support for fishery policies in Oslob and Santander. Fish catch was a better predictor for public support for fishery policies in Samboan. Results can help local governments, non-governmental organizations, and fishery managers to prioritize, plan, and improve fisheries management in municipal waters.  相似文献   

18.
叶伟明 《中国水运》2006,6(6):28-29
海上养殖业也处于高速发展期,并成为部分地区重要的区域支柱产业,但随意建立或扩大养殖区域对船舶正常的海上航行安全构成严重的威胁,海上交通安全与海洋养殖的矛盾已日趋突出。本文介绍了海上养殖区的设立应具备的必要条件,并客观的提出了船舶触损海上养殖区事故调处的法律法规理解和处理方式。  相似文献   

19.
Parasitic copepods belonging to two orders, Siphonostomatoida and Poecilostomatoida, are frequently reported from fish hosts in the deep sea. Three families of copepods are most commonly encountered, Sphyriidae, Lernaeopodidae and Chondracanthidae, but members of another four families, Hatschekiidae, Pennellidae, Philichthyidae and Hyponeoidae, are occasionally recorded. These parasites utilise various deep demersal fishes as hosts, especially species of the most abundant families, Macrouridae, Moridae, Synaphobranchidae and Alepocephalidae. Host specificity levels are variable, as for shallow-water fishes. In contrast, few parasites are regularly reported from fishes inhabiting the pelagic water column away from the bottom and away from the near-surface zone. Only the pennellids Sarcotretes scopeli and Cardiodectes medusaeus appear common on pelagic fishes, in the Atlantic and Pacific respectively. Host specificity levels in these two pennellid species are relatively low. It is speculated that the difficulty of encountering a host in the vast pelagic biome has restricted the diversity of parasitic copepods that have successfully colonized pelagic fishes.  相似文献   

20.
新型高效吸鱼泵由双真空泵、双吸鱼筒组成,利用双筒交替吸鱼、排鱼,可实现连续鱼虾起捕,其效率是单筒间歇式吸鱼泵的1.5倍以上,有效解决了传统真空吸鱼泵存在的效率低、功耗大的问题;双真空泵可互为备用,也可轮流使用,通过冗余设计提高设备的可靠性,这对远洋捕捞业尤为重要;该吸鱼泵采用真空负压抽吸和零压排放原理,有效提高活鱼成活率;主吸鱼管采用套管式结构,可在水平、垂直方向灵活伸缩;控制系统采用全程自动化控制。  相似文献   

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