Long-term monitoring of the individual self-feeding behavior of rainbow trout Oncorhynchus mykiss

Self-feeding device is extensively used in aquaculture farms, but for salmonids the individual feeding behavior has seldom been continuously observed. In this article, the individual self-feeding behavior of 10 rainbow trout was continuously monitored with a PIT tag record for 50 days with three replicates. The fish fell into three categories according to their feeding behavior, i.e. high triggering fish (trigger behavior more than 25% of the group, HT), low triggering fish (1%–25%, LT) and zero triggering fish (less than 1%). The results showed that in a group of 10 individual 1–2 HT fish accounted for most of the self-feeding behavior (78.19%–89.14%), which was far more than they could consume. The trigger frequency of the fish was significantly correlated with the initial body weight (P <0.01), however, no significant difference in growth rate among the HT, LT, and ZT fish was observed (P >0.05). Cosinor analysis showed that the two HT fish in the same group had similar acrophase. Though some of the HT fish could be active for 50 d, there were also HT fish decreased triggering behavior around 40 d and the high trigger status was then replaced by other fish, which was first discovered in salimonds. Interestingly, the growth of the group was not affected by the alternation triggering fish. These results provide evidence that in the self-feeding system the HT fish didn’t gain much advantage by their frequent self-feeding behavior, and high trigger status of the HT fish is not only an individual character but also driven by the demand of the group. In the self-feeding system, the critical individual should be closely monitored.

     

长江口外海域三维水动力模拟结果及与观测的比较

Base on ECOMSED model, a theree-dimensional hydrodynamic model is developed in the offshore area near the Changjing Estuary in the East China Sea. This model in driven by tide and wind,as well as inflow and outflowcurrents such as Kuroshio,Changjing runoff. The horizontal resolution is 1/20_°. There have 11 layers on the verticaldirection. The numerical results of 4 main constituents of tide(M²,S²,K¹,O¹)and currents are in good agreement with observation data. Compared with 20 gauge stations,the mean absolute erroe between the caluclated M² tidal amplitude and the observed oned is only 6.72cm; the mean absolute error of phased-lag is 5.23_°.For S²,the mean absolute errors of amplitude and phased-lag are 3.67cm and 7.21_°,respectively. The mean absolute errors of amplitude and phased-lag for K¹ are 3.25cm and 6.63_° For O¹,the mean absolute error of calculation and observation is relatively small, amwith observation data measured during Aug., 2006 in the East China Sea.The correlation coeffiients of current between simulation and observation are greater than 0.75 generally. The three-dimensional hydrodynamic model develiped by this paper can well describe the characters of elevation and current in the offshore near the Changjiang Estuary and can be used as hydrodynamic background to simulate the suspend sediment transport in this sea area.     

正理庄高89-1区块CO2混相驱参数优化数值模拟研究

为了确保高89-1区块CO2混相驱项目的顺利实施,依据该区块的精细油藏描述成果,在优化适于CO2混相驱模型基础上,建立了符合油藏地质特点的三维地质模型。在此基础上对开发指标进行计算,对五个参数（井网、开发方式、压力水平、注入量和采油速度）进行优化,并提出了推荐方案,预测采收率可达23.10%,比弹性开采方式提高15.16%。     

数字化测绘生产管理有关问题研究

数字化测绘生产的特点,带来了生产管理的复杂性和特殊性。数据生产的管理控制,需要把握好顾客需求、技术设计、生产计划、调度控制、质量管理等关键的环节,处理好生产过程中产生的相关问题。     

DSS模型系统建模与实现方法研究及其在海洋中的应用

把进程代数(Process Algebra简称PA)引入到DSS模型系统建模中来,提出了一种新的DSS模型建模理论体系,该建模理论可以描述模型之间激发、使用、选择、重复、同步和并发等行为：建立了该建模理论体系与组件对象模型的对应关系,提出了基于组件技术的模型系统实现方法,并通过一个海洋实例给出实现方法的具体应用。     

Environmental impact of fluidized solidified silt casting on surrounding water bodies

Abstract

With the growing demand for underwater refill engineering, the construction technology of implementing fluidized solidification in underwater pouring has recently received increased attention. However, the environmental impact of underwater casting on surrounding water bodies, especially when the silt is polluted, is still unclear. In this study, a simulated underwater pouring test and a static immersion release test were conducted separately to study the quality of the surrounding water during and after pouring. The results showed that fluidized-solidified silt casting could increase the pH of the surrounding water, even after the pouring had stopped, by approximately 1.0 and the turbidity could reach 200 NTU. No diffusion of Zn and Cu into the surrounding water was observed and while Ni and Cr exhibited slight diffusion, this was at a level well below international water quality standard. During construction, reducing the distance from the seafloor to the bottom of the pouring catheter could reduce the level of pollution. After construction, the use of neutral solidified materials can effectively reduce the pH of the surrounding water and the potential risk of heavy metal dissolution.     

Effect of slow-solvent-vapour treatment on performance of polymer photovoltaic devices

In this work, enhanced poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) bulk-heterojunction photovoltaic devices are achieved via slow-solvent-vapour treatment. The correlations between the morphology of the active layer and the photovoltaic performance of polymer-based solar cell are investigated. The active layers are characterized by atomic force microscopy and optical absorption. The results show that slow-solvent-vapour treatment can induce P3HT self-organization into an ordered structure, leading to the enhanced absorption and efficient charge transport.     

人类活动影响下华北平原地下水环境的演化与发展

本文是研究华北平原第四系地下水系统在自然条件并叠加人为因素影响的地下水动力场和地下水水化学场演化与发展的综合性环境地学课题的成果。主要研究了地下水系统通过包气带与外部环境要素间物质与能量的传输;地下水地球化学环境演化规律;华北平原地下水超量开采区的地下水循环系统及其演变规律和地下水环境演化预测。     

粘性土微观结构简易定量分析法

作者根据计算机图像处理的基本原则，探索出一套粘性土微观结构简易定量分析法，经检验，这种方法简易，有效，对推广岩土结构定量化具有重要意义。