Does the Amati Relation depend on the Luminosity of the GRB＇s Host Galaxy？

In order to test the systematics of the Amati relation, 24 long-duration GRBs with available Eγ,iso, and Ep are separated into two subgroups according to the B-band luminosity of their host galaxies. The Amati relations in the two subgroups are found to be in agreement with each other within the uncertainties. Taking into account of the well established luminosity-metallicity relation of galaxies, no strong evolution of the Amati relation with the GRB's environmental metallicity is implied in this study.     

西秦岭寨上金矿综合地球物理研究

寨上金矿是中国西秦岭构造带内一个重要的超大规模卡林—类卡林型金矿床.以往对该金矿床的研究主要集中在矿床学、年代学和成矿特征等方面,缺乏地球物理工作的系统梳理.本文以贯穿研究区的可控源音频大地电磁测深及激电工作为主体研究寨上金矿的深部结构,结合地质资料建立了矿区典型地质—地球物理解释模型,探讨成矿机制,总结寨上金矿赋矿标...     

Bohai Sea oil spill model: a numerical case study

An operational Bohai Sea oil spill serving module (BSOSSM) that can provide users with trajectory and movement information of the released oil is developed for the purpose of informing mitigation of oil spill incidents in the Bohai Sea, China. BSOSSM is one of the serving modules that had been integrated in China digital ocean prototype system, a marine information platform for managing, displaying and disseminating all the data investigated by China 908 Program. The oil spill trajectory is calculated by an oil spill model (OSM), which serves as a component in BSOSSM. The impacts of wind, current, as well as Stokes drift on oil spill trajectory are studied by sensitivity experiments conducted using OSM. Simulation results indicate that wind forcing is the most important factor in controlling the oil trajectory at the sea surface in Bohai Sea, whereas current and Stokes drift play relatively less important roles. However, because the direction of waves generally follows that of the wind, Stokes drift does lead to an increase in oil drift and spreading velocity. Case studies of the Penglai 19-3 oil spill incident (June 2011) and Xingang oil spill (April 2005) demonstrate that OSM can generally reproduce the oil spreading, and is therefore capable of supporting the emergency response of future oil spills in the Bohai Sea through BSOSSM.     

LVP modeling and dynamic characteristics prediction of a hydraulic power unit in deep-sea

A hydraulic power unit(HPU) is the driving "heart" of deep-sea working equipment.It is critical to predict its dynamic performances in deep-water before being immerged in the seawater,while the experimental tests by simulating deep-sea environment have many disadvantages,such as expensive cost,long test cycles,and difficult to achieve low-temperature simulation,which is only used as a supplementary means for confirmatory experiment.This paper proposes a novel theoretical approach based on the linear varying parameters(LVP) modeling to foresee the dynamic performances of the driving unit.Firstly,based on the varying environment features,dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing.Secondly,models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer,and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration.Thirdly,dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters.Finally,the developed HPU is tested in a deep-sea imitating hull,and the experimental results are well consistent with the theoretical analysis outcomes,which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU.The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump.     

Assessment of Unconfined Compressive Strength of Cement Stabilized Marine Clay

Two aspects of deep mixing method, the difference relating strength gain in dry jet mixing (DJM, reagent powder introduced into the ground) and cement deep mixing (CDM, reagent slurry introduced into the ground), and prediction of unconfined compressive strength of cement stabilized marine clay, are discussed in this paper. The first part of this paper concentrates on the difference between DJM and CDM on strength gain, and suggests a guideline for DJM and CDM selection. An indicator in terms of water content ratio, which is defined as the ratio of water content to the liquid limit of the soil, is presented by statistical analysis from the laboratory and field test data as a guideline for the selection of DJM or CDM. Based on the laboratory test data, a mathematical model relating strength gain of cement stabilized marine clay to related variables is developed. A new simple index designated as total water-cement ratio, which is defined as the ratio of water weight in the soil-cement to the weight of cement in dry state, is proposed for interpretation of test data of soil-cement. The proposed method is then verified with available test data published by other different researchers.     

A method of making deepwater shallow sediments considering their rehological properties

Abstract

In this article, based on the rheological consolidation model of deepwater shallow sediments, the artificial samples were made in laboratory. The feasibility of artificial samples was verified by electron microscopy scanning and triaxial experiments. Deepwater shallow sediments consolidation models mainly considers two points: (i) the change of permeability with time and temperature and (ii) the effect of rheology. The consolidation experiment of deepwater shallow sediments verifies the correctness of the model. It can be found that, the artificial and natural samples have the same physical and mechanical properties. And the physical properties of natural samples can be obtained by rheological consolidation model of deepwater shallow sediments.     

A Conditional Dependence Adjusted Weights of Evidence Model

One of the key assumptions in weights of evidence (WE) modelling is that the predictor patterns have to be conditionally independent. When this assumption is violated, WE posterior probability estimates are likely to be biased upwards. In this paper, a formal expression for the bias of the contrasts will be derived. It will be shown that this bias has an intuitive and convenient interpretation. A modified WE model will then be developed, where the bias is corrected using the correlation structure of the predictor patterns. The new model is termed the conditional dependence adjusted weights of evidence (CDAWE) model. It will be demonstrated via a simulation study that the CDAWE model significantly outperforms the existing WE model when conditional independence is violated, and it is on par with logistic regression, which does not assume conditional independence. Furthermore, it will be argued that, in the presence of conditional dependence between predictor patterns, weights variance estimates from WE are likely to understate the true level of uncertainty. It will be argued that weights variance estimates from CDAWE, which are also bias-corrected, can properly address this issue.     

西藏当雄6.6级地震与尼木6.5级地震震害特征分析

2008年10月6日16时30分在西藏拉萨市当雄县（北纬29°48′,东经90°21′）发生了Ms6．6级地震,而在1992年7月30日16时24分在拉萨市尼木县（北纬29°35′,东经90°15′）曾发生过Ms6．5级地震。上述2次地震发生在同一活动构造带上,地震类型相同,震级、震源深度也相差不大,但2次地震造成的灾害损失却相差很大。作者在地震现场调查的基础上,对比分析了这2次地震的人员伤亡和震害情况,探讨了造成地震灾害损失轻重的主要因素。     

基于多源空间数据的鲁中北五湖近100年变化分析

北五湖系鲁中黄河以南自北向南分布的一系列湖泊,分别为安山湖、马踏湖、南旺湖、蜀山湖和马场湖。近100年来,北五湖陆续淤废,目前,除安山湖、马场湖尚有残存外,其他诸湖悉数消亡。作者收集了北五湖地区1907年测绘地图、成像于1954年的航片、成像于1975年的MSS遥感影像、分别成像于1987年、2001年的TM遥感影像以及成像于2005年的SPOT5 XS遥感影像等6个时段的数据。对其进行了几何纠正与配准、图像镶嵌等预处理,通过目视解译和遥感分类等手段提取了该地区6个时期的北五湖空间分布数据。根据北五湖6个不同时段的空间展布特征,分析了近100年以来北五湖消亡的幅度、速度和时间等特征,并在此基础上初步探讨了北五湖消亡的原因。     

美国WoS数据库收录的中国南北极研究论文的调研与分析

通过美国的核心期刊数据库,收集了中国作者自1982年以来在世界核心期刊上所发表的有关南北极研究方面的文章,在此基础上进行了基本的文献计量学分析,包括各年文献量、期刊、著者、地区、机构、研究主题、引文等,以期从一个侧面来反映中国南北极研究方面的科研生产率、核心机构、核心人员、核心期刊、主要的研究领域、具有国际影响力的研究成果、发展趋势等信息,便于人们通过定量数据来了解中国南北极研究的现状、布局和实力。