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11.
基于粒子群算法的浮筒配置优化问题的研究   总被引:1,自引:0,他引:1  
针对传统的验证法在解决浮筒配置问题中存在的计算量大、计算时间长、工作重复性强等缺点,提出了一种将浮筒纵向位置配置和浮筒充气量综合考虑、一体优化的方法。文章将各种合理性校验准则作为约束条件,通过逼近沉艇起浮瞬间和浮起后的平衡状态,来求取各对浮筒的纵向位置和充气量,将浮筒配置问题转换为一个多目标、多约束的最优化问题。在此基础上,根据粒子群优化算法的特点,提出了一种双向搜索策略,来求解浮筒配置优化问题。这种方法简单实用,计算时间短,无需人工干预,算法运行一次可获得多组配置方案供决策人员选择。算例表明用这种方法来解决浮筒配置问题是可行的、有效的。  相似文献   
12.
Mooring optimization of floating platforms using a genetic algorithm   总被引:1,自引:0,他引:1  
This paper presents a new procedure for the optimization of the mooring design of floating platforms, in which an automatic design sequence is also established. Regarding the optimization philosophy, the following aspects are dealt with:
• The optimization of the platform heading and its mooring pattern, taking into account the environmental force spreading;
• optimum line length or line tension for each mooring line, associated to the optimization of the mooring line materials and sizes.
Basically, the main goal of this paper is to introduce a new method, which will provide the quickest way to find the best mooring system, defined here as that which minimizes platform responses.A genetic algorithm (GA) is applied in this contribution, and this paper describes exactly the procedure of developing a GA code directed toward the solution of mooring design optimization problems. In order to prove the efficiency and the vast potential of the proposed algorithm as a design tool, sample moorings are analyzed for different environmental conditions and the final results, including the time required to run them, are presented.  相似文献   
13.
利用琼胶作为唯一的碳源从青岛太平角海域的海水和红藻样品中筛选分离得到一株高产琼胶酶的海洋菌F-6,对其最适的产酶条件,利用琼胶酶分离条斑紫菜的原生质体和原生质体的培养进行研究。结果表明,通过单次单因子和正交实验确定琼胶降解菌株F-6最适产酶培养基配方为(W/V):琼胶0.7%;酵母粉0.3%;蛋白胨0.5%;NaCl2.0%;K2HPO40.1%;CaCl20.02%;MgSO4·7H2O0.05%;FeSO4·7H2O0.002%;起始pH=7.5,最适的发酵产酶条件为:26℃培养36h。经条件优化后,粗酶液的酶活高达631.6U/ml。发酵液经过6000g离心30min得到粗酶液,粗酶液经过8k分离膜超滤,加入1mol/L渗透剂,0.22μm滤膜过滤除菌后降解条斑紫菜组织块,成功地分离得到大量的紫菜原生质体,其产率为3×106个原生质体/g新鲜紫菜组织。原生质体经初步培养发育成愈伤组织,其成活率为60%。  相似文献   
14.
王彦飞  邹安祺 《岩石学报》2018,34(2):281-288
页岩气成藏机理与页岩内部孔隙结构紧密相关,对页岩孔隙结构的研究成为页岩气勘探开发技术中至关重要的一环。页岩内部不同结构体组分对X-射线的吸收能谱不一样,这样就导致观测数据是由不同页岩组分衰减不同波段的X-射线构成的。经过对CT图像分割,能够获得页岩微孔结构的图像,尤其是获得有机质中孔隙类别、形状、尺寸、空间分布、连通特性。本文利用同步辐射X射线扫描重构的页岩CT数据,研究并设计基于多能CT图像的神经网络图像分割技术和算法,以期得到页岩体三维结构特征及空间分布,可以为建立有机质种类和无机矿物组成与微纳孔隙特征的联系以及最终实现页岩气的资源储量评估和勘探开发提供技术支持。  相似文献   
15.
利用1951-2013年广西90个气象观测站气温资料、国家气候中心74项指数和美国National Oceanic and Atmospheric Administration(NOAA)的Climate Prediction Center(CPC)60项指数以及海温和陆地雪盖资料、美国国家冰雪研究中心(NSIDC)的两极海冰资料,使用相关分析方法得到广西寒露风开始期气候影响因子,利用逐步回归和神经网络方法进行寒露风开始期的预测。结果表明:寒露风开始期与前一年9-10月北极海冰面积、当年3月南极海冰面积、前一年6月欧亚雪盖、当年5月北美雪盖、北半球雪盖的相关显著。与前一年9月北半球极涡面积指数、前一年10月亚洲区极涡面积指数、前一年3月热带印度洋海温偶极子等指数相关显著。粒子群-神经网络方法预测误差低于逐步回归方法,预报能力有明显提高。  相似文献   
16.
Hsin-Hung Chen   《Ocean Engineering》2008,35(10):983-994
Parameter identification of a remotely operated vehicle (ROV) is often based on the dynamic responses collected by its onboard sensors. However, for commercial ROVs, the required data for identification may not be available due to the absence of suitable sensors or limitations in accessing onboard sensor data. Therefore, this study proposes a vision-based tracking system to measure the dynamic response of an ROV. The tracking system is independent of the ROV, and is able to localize an ROV to a high degree of precision by means of projective mapping. The validity of the proposed tracking system is demonstrated through identification of a commercial ROV. A simplified nonlinear ROV dynamic model with six degrees of freedom (DOF) is used for identification. Uncoupled motions, including surge, sway, and yaw, are obtained from the ROV dynamic model, and the corresponding experiments are carried out for each DOF. Hydrodynamic parameters are then estimated with numerical optimizations by comparing the measured ROV responses with the output of the mathematical model. The experimental results show that the vision-based tracking system can accurately measure the transient and steady-state responses of an ROV. Additionally, the simulations of the ROV dynamic model, with the optimal parameter estimates, give results in agreement with the measured data.  相似文献   
17.
A Spatial Ecosystem and Population Dynamic Model (SEAPODYM) is used in a data assimilation study aiming to estimate model parameters that describe dynamics of Pacific skipjack tuna population on ocean-based scale. The model based on advection–diffusion–reaction equations explicitly predicts spatial dynamics of large pelagic predators, while taking into account data on several mid-trophic level components, oceanic primary productivity and physical environment. In order to improve its quantitative ability, the model was parameterized through assimilation with commercial fisheries data, and optimization was carried out using maximum likelihood estimation approach. To address the optimization task we implemented an adjoint technique to obtain an exact, analytical evaluation of the likelihood gradient. We conducted a series of computer experiments in order to (i) determine model sensitivity with respect to variable parameters and, hence, investigate their observability; (ii) estimate observable parameters and their errors; and (iii) justify the reliability of the computed solution. Parameters describing recruitment, movement, habitat preferences, natural and fishing mortality of skipjack population were analysed and estimated. Results of the study suggest that SEAPODYM with achieved parameterization scheme can help to investigate the impact of fishing under various management scenarios, and also conduct forecasts of a given species stock and spatial dynamics in a context of environmental and climate changes.  相似文献   
18.
郭谦 《国土资源遥感》2008,19(3):104-107
层次分析法(Analytical Hierarchy Process,AHP),是一种常用的系统分析与决策方法,但在应用于青藏高原区域生态环境综合评价时,由于因素的权重值只能为正数,影响了表达效果。为此,本文对其进行了优化,改进了构造判断矩阵时的赋值方法,在评价过程中引入了负数。实验证明,优化后的方法能准确地评价青藏高原的生态环境。  相似文献   
19.
对一株分泌热稳定κ-卡拉胶酶印尼热泉菌进行了种属鉴定, 并采用响应面法对该菌发酵产酶条件进行了优化。鉴定结果表明, 该菌株属于芽孢杆菌属(Bacillus), 命名为Bacillus sp. Car19(GeneBank: KT865196)。发酵条件优化结果显示, 9个环境因子影响Bacillus sp. Car19产酶量。其中影响Bacillus sp. Car19产酶量的三个主要因素分别为培养温度、培养基中Cu2+浓度和培养基中NaCl浓度。综合次要因素对Bacillus sp. Car19产酶影响, Bacillus sp. Car19最佳产酶发酵条件为: 培养温度52.31℃、Cu2+浓度6.93 mmol/L、NaCl浓度37.03 g/L, 培养基pH为6, 接种量1%, 培养时间36h, 半乳糖浓度0.3 g/L,硝酸铵浓度7g/L, 卡拉胶浓度0.5g/L。优化后发酵上清液酶活力达到15.21 U/mL, 与优化前相比提高了1.5 倍。  相似文献   
20.
Analysis of multivariate response data by modelling the principal components of the response has beenapplied to two sets of data. In both cases principal components analysis revealed the relationships amongthe response variables and exploited them to simplify the problem of modelling and optimizing themultivariate response. The models and optima obtained from the principal components comparedfavourably with the individual models and simultaneous optima.  相似文献   
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