2018-01-23阿拉斯加海啸的数值模拟研究

利用Okada模型计算2018-01-23 09:31（UTC）阿拉斯加湾7.9级地震引发的海啸的初始场信息,利用COMCOT模型模拟海啸传播。比较海啸首波振幅和到达时间模拟值与实测值显示,振幅差异在4 cm以内,时间差异在4 min以内。模拟结果与观测资料吻合,揭示阿拉斯加地震引发的海啸强度弱,同时反映海啸初始场参数的选择合理有效,海啸模拟计算结果真实可靠。     

山东威海滨海新城北部海域潮流数值模拟研究

山东省威海市滨海新城作为威海市的新行政中心,是威海市着力打造的宜居、宜业、宜游、宜学的现代化卓越新城。本文采用MIKE21FM平面二维数值模型研究威海市滨海新城北部海域的潮流场运动,并以分层流速流向实测资料对模型进行验证。结果表明,研究区潮流场流速和流向数值模拟结果与实测资料变化基本一致。     

北部湾海域秋、冬季甲壳类的种类组成及分布

根据 2 0 0 1年 11至 2 0 0 2年 1月间北部湾海域秋、冬季 2个航次的底拖网渔业资源调查资料 ,对北部湾海域甲壳类的种类组成及分布进行研究。本次调查共渔获虾类 2 4种 ,隶属于 6科 11属 ;蟹类 30种 ,隶属 9科 19属 ;虾蛄 9种 ,隶属 2科 6属。各种类沿水深和地理分布有明显变化 ,主要集中分布于湾中部水深 2 1～ 80m海域。     

钻孔应变观测影响因素的数值模拟分析

利用有限元数值模拟方法,研究在非均匀地应力作用下,钻孔开挖前后区域应力场的变化特征,并探讨钻孔开挖后岩石、水泥、探头的弹性模量、泊松比及水泥的厚度与膨胀系数的变化对分量应变及面应变观测的影响。研究结果表明：钻孔开挖造成区域应力场扰动的范围大概为1.5倍孔径。在“探头 水泥环 围岩”系统中,各参数的变化对应变观测的影响程度不同,但分量应变对外界载荷的响应趋势基本一致。在均匀地应力作用下,水泥厚度对应变的影响与水泥的弹性模量有关,且随着水泥膨胀系数的增加,面应变存在减小的趋势。     

流变特性对青藏高原构造变形影响的数值模拟

建立三维黏弹性有限元模型,采用标准线性固体本构关系,分析流变特性对青藏高原现今构造变形的控制作用。模拟结果显示：1）在高原地壳介质流变机制的控制下,青藏高原内部从西向东,东向位移分量逐渐增大。最大值出现在甘孜 玉树 鲜水河断裂带区域内,反映了青藏高原的物质东移运动;2）在菱形块体中南部,其东侧区域向东南方向运动,而其西侧区域则转向西南方向运动;3）中地壳强流变模型与下地壳强流变模型给出的计算结果总体特征相似,二者均能较好模拟高原物质东流以及绕喜马拉雅东构造结的顺时针转动;4）流变特性对青藏高原构造变形特征的影响较大。     

不确定性对北部湾二长棘鲷渔业资源评估影响的模拟研究

利用蒙特卡罗模拟方法研究了生物学参考点F0.1、Fmax和当前捕捞死亡系数(current fishing mortality rate,Fcur)估计中的不确定性对北部湾二长棘鲷渔业资源评估的影响。结果表明:二长棘鲷渔业资源状态评估受到F0.1、Fmax、Fcur估计中的不确定性和管理者选取的决策置信水平的影响,二长棘鲷渔业被确定为过度捕捞的概率随着F0.1、Fmax、Fcur估计中不确定性和置信水平的增加而下降;F0.1和Fmax估计中的不确定性主要由生长参数的不确定性引起,自然死亡系数的不确定性对F0.1和Fmax估计中的不确定性的影响是有一定限度的。相比Fmax,将F0.1作为二长棘鲷渔业的管理目标更为合适。     

某高速公路滑坡的数值模拟及后缘坡体稳定性分析

通过对诸永高速公路台州段1#滑坡(K120 085～K120 169)工程地质特征的分析,指出沿线区存在很多因修建公路引发的工程滑坡问题,然后采用边坡稳定性FLAC/Slope分析软件,对滑坡滑动前、后工况下稳定性进行数值模拟,并对滑移后的后缘坡体稳定性进行了数值分析.剪应变率云图和稳定性分析结果表明,滑动后的后缘坡体仍处于不稳定状态,又形成了新的滑坡体.     

栗西栗峪河系氟污染的数值模拟

本文在野外水文地质调查的基础上,通过概化河流水质模型、确定计算参数和采用有限差分法来离散水质模型的办法,用计算机模拟了不同排污状态、不同水文特征下该河系水中氟浓度的年份变化规律,从而为评价该河系水中氟污染程度提供了定量依据。     

5·15广东大暴雨数值模拟及中尺度分析

利用WRF3.5模式对2013年5月15-17日发生在广东的大暴雨进行了数值模拟,并对大暴雨强降水时段中尺度系统的动力机制、热力条件及演变做了进一步的分析。结果表明:WRF3.5模式能较好地模拟出大暴雨过程的强降水中心、降水强度及雨带分布的变化趋势。稳定的"两槽一脊"形势是大暴雨发生的有利背景条件。高空辐散、低空辐合的有利配置及其耦合产生次级环流,同时地形对迎风坡的西南气流有阻滞和抬升,是大暴雨过程的主要动力机制。爆发的南海夏季风输送的充沛水汽在强垂直运动和弱冷空气作用下释放的大量能量是此次大暴雨过程的热力条件。中高层弱冷空气在次级环流的作用下向低层侵入,与上升的暖湿空气相互作用,促使斜压不稳定和对流不稳定的释放和发展,是大暴雨的触发机制。     

任意结构的电容耦合直流放电的数值模拟

本文描述了二维模型下电容合的直流放电计算过程。发展了适用于任意结构下非正交坐标系的算法。提出了决定边界条件的相关技术，程序设计中发展了网络生成系统，使程序更适用，并且用图表说明了半导体机械中的一种典型的应用。     

Counter-Wind Deep Current in the Northern Beibu Gulf in Boreal Winter

The Beibu Gulf is at an important geographical location and rich in gas, oil and biological resources. The observed currents showed that the current in the upper layer was opposite to that in the lower layer in boreal winter in the northern Beibu Gulf and it was northeastward in the lower layer. This northeastward current was reproduced by a 3 D baroclinic model in this study. It's found that the counter-wind deep current(referred to as ‘CWDC' hereinafter) strengthened from September to November but weakened from December to the following February. A closed meridional circulation in vertical direction was found in the northern Beibu Gulf, including CWDC, surface southwestward current, an upwelling, and a downwelling. The temporal variation process of the meridional circulation was similar to that of CWDC, with strength and range stronger in November and December than in other four months. Similar to the variation process of CWDC, the monsoon wind changed from weak easterly wind in September to strong northeasterly wind in November and December, and it was transformed into weak southeasterly wind in February again. The sensitive experiments showed that CWDC and the meridional circulation were controlled by the monsoon wind and were adjusted by heat flux-and tide-induced mixing, respectively. According to the momentum balance equation, it can be revealed the counter-wind deep current is a compensation current which is induced by the surface elevation gradient balanced by the Coriolis force, vertical diffusion and baroclinic pressure gradient.     

北部湾二长棘鲷生长、死亡及其群体组成

利用2006年7月至2008年3月北部湾渔业商业捕捞底拖网和刺网渔获物中采集的样本,对北部湾二长棘鲷的生长、死亡及其群体组成进行了初步研究。结果表明,北部湾二长棘鲷优势体长70～140 mm,占82.2%;优势体重为20～60 g,占54.29%;ARSS分析表明雌雄生长不存在显著性差异(P>0.05),繁殖期性比为1.21∶1;von Bertalanffy生长方程的主要参数分别为:L∞=292.8 mm,K=0.167,t0=-1.116;体重的生长拐点为5.463龄;总死亡系数、自然死亡系数和捕捞死亡系数分别为1.041 4、0.282 8和0.752 6,当前开发率为0.728。     

THE HOLOCENE ALONG THE COAST OF HAINAN ISLAND, CHINA

Based on the new data of the Quaternary along the coast of Hainan Island, China, this paper puts forward that the Holocene in Hainan Island can be divided into four formations: Wanning formation (Q41), Sanya formation (Q42-1), Qiongshan formation (Q42-2) and Ledong formation (Q43). Spore-pollen analysis shows that there are 6 spore-pollen zones existed, reflecting two cycles of climatic fluctuation from warm-dry to hot-humid. The climax of hot-humid period occurred 6,000-5,000 years B.P.. Based on the 14C dating data of the 38 samples representing the positions of ancient sea level, a breakthrough curve representing the sea level change during the Holocone is obtained, in which , a sea level change caused by tectonic movement is subtracted. Two cycles of rise-drop of sea level with three periods of high sea level were found. The period with the highest sea level is some 6,000-5,000 years B.P.. According to the rise-drop rate of sea level, four periods of the sea level change can be distinguished in the     

北部湾江洪扇贝养殖区的污损生物

2006年8月至2007年7月,对北部湾江洪扇贝养殖区的污损生物进行周年调查。结果表明:该海区养殖网笼的污损生物有8门20种,优势种为藤壶、钩虾、苔藓虫,其次是翡翠贻贝、牡蛎、海鞘、大型藻类和水螅。污损生物附着高峰在8、11和12月,1月的附着数量最少;藤壶附着高峰在8、11和12月,附着生物量占污损生物总量的56.0%,是养殖区污损生物防除的重点对象;钩虾附着高峰出现在8、9月,12和2月附着量也较高,其生物量占污损生物总量的18.0%;草苔虫附着高峰出现在4月,其生物量占污损生物总量的8.4%。污损生物附着量呈现由表层向底层递减的趋势。     

Research on the macrodevelopment strategy of Hainan Island

There is a great difference in starting conditions among Hainan Island, the special economic zones and the economic and technological development zones in China, and "the Four Small Dragons" of Asia. Hainan's major superiority is superiority of the special economic zone. The superiority includes two main parts of natural resources and geographical location. In order to give play to the superiority it is necessary to develop the export-oriented economy. As for giving full play to the location superiority, it must be solved that the problems on the investment, the talent and the development models. It is very important to rely on the superiority of natural resources to develop the products which is necessary for our country and can replace the imports. The rational adjustment on the economic departments in Hainan Province comprises two aspects. The departments of exploiting natural resources must enlarge the processing depth of agricultural products and industrial raw materials, and increase the additiona     

基于底拖网调查数据的渔业资源质量状况评价体系构建——以北部湾为例

【目的】构建渔业资源质量状况评价体系,评估渔业管理成效,服务海洋渔业可持续发展。【方法】以北部湾底拖网调查数据为基础,结合渔业统计数据,构建渔业资源质量状况评价指标体系。该体系分3个层次,下设7项指标。通过专家经验法和平均赋值法对指标进行赋值,得到各指标权重,建立质量状况评价等级指数,并利用该等级指数对北部湾渔业资源进行评价。【结果与结论】1992―2017年北部湾渔业资源评价指标中有6项呈下降趋势;质量状况评价等级指数波动在0.44~0.56之间。自20世纪90年代以来,北部湾渔业资源一直处于临界状态。该评价结果与北部湾渔业资源利用的实际状况基本相符,证明该方法具有合理性和可操作性,可为其他海区渔业资源质量状况评价提供借鉴。     

Age and Growth Characteristics of Crimson Sea Bream Paragyrops edita Tanaka in Beibu Gulf

Age and growth characteristics of crimson sea bream Paragyrops edita Tanaka in Beibu Gulf were studied through bot-tom trawling and gillnet fleets fishing from July 2006 to December 2007.A total number of 1155 individuals,ranging from 49 to 249mmin standard length was examined.The age of the fish was determined from sagittal otoliths.One year growth was made up of onetranslucent and one opaque zone.A maximum likelihood estimation procedure was used to fit the Von Bertalanffy,Logistic andGompertz growth functions to the length-at-age data.ARSS indicated that there were no significant differences in growth betweensexes in the three growth models (P>0.05),and the Von Bertalanffy growth function L<,t>=292.8{1-exp[-0.167(t 1.116)]} was se-lected as the most appropriate growth model according to Akaike's information criterion (AIC).     

Using otolith weight to predict the age of Pennahia macrocephalus in the mouth of the Beibu Gulf

The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs (P≧>0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmned by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age (P<0.05). The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittai OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore,the technique is applied for Pennahia macrocephalus with discussion in this paper.