腐败原因新探

现代化过程中物质条件迅速发展是腐败行为产生的催化剂;现代化对政治体制输出方面造成的变革是腐败的助推器;现代化促使人的价值观发生转变完成了腐败“从无到有”的转换。腐败的产生还与该国进入现代化时期之前的传统社会性质密切相关。     

破碎的系统观

论文讨论了:1、中国传统系统观的基本特征,它们是,普遍主义的大一统的系统观;基础主义和整体主义的系统观;2、科学实践哲学和新经验主义科学哲学蕴含的多元主义的地方性系统观;3、多元主义地方性系统观对于系统科学的意义。     

新环境下中文纸质期刊采访工作的走向初探——以武汉大学图书馆为例

阐述了中文纸质期刊采访所面临的新变化,提出了新环境下中文纸质期刊的采访策略,强调应坚持纸本期刊与电子期刊订购时不割裂、纸本订购期刊与赠送交换期刊订购时不割裂的做法。     

Subtypes of medulloblastoma have distinct developmental origins

Medulloblastoma encompasses a collection of clinically and molecularly diverse tumour subtypes that together comprise the most common malignant childhood brain tumour. These tumours are thought to arise within the cerebellum, with approximately 25% originating from granule neuron precursor cells (GNPCs) after aberrant activation of the Sonic Hedgehog pathway (hereafter, SHH subtype). The pathological processes that drive heterogeneity among the other medulloblastoma subtypes are not known, hindering the development of much needed new therapies. Here we provide evidence that a discrete subtype of medulloblastoma that contains activating mutations in the WNT pathway effector CTNNB1 (hereafter, WNT subtype) arises outside the cerebellum from cells of the dorsal brainstem. We found that genes marking human WNT-subtype medulloblastomas are more frequently expressed in the lower rhombic lip (LRL) and embryonic dorsal brainstem than in the upper rhombic lip (URL) and developing cerebellum. Magnetic resonance imaging (MRI) and intra-operative reports showed that human WNT-subtype tumours infiltrate the dorsal brainstem, whereas SHH-subtype tumours are located within the cerebellar hemispheres. Activating mutations in Ctnnb1 had little impact on progenitor cell populations in the cerebellum, but caused the abnormal accumulation of cells on the embryonic dorsal brainstem which included aberrantly proliferating Zic1(+) precursor cells. These lesions persisted in all mutant adult mice; moreover, in 15% of cases in which Tp53 was concurrently deleted, they progressed to form medulloblastomas that recapitulated the anatomy and gene expression profiles of human WNT-subtype medulloblastoma. We provide the first evidence, to our knowledge, that subtypes of medulloblastoma have distinct cellular origins. Our data provide an explanation for the marked molecular and clinical differences between SHH- and WNT-subtype medulloblastomas and have profound implications for future research and treatment of this important childhood cancer.     

上海世博会出行方式选择意愿的建模与场景分析

针对2010年上海世博会客流来源广泛、背景差异大的特点,设计了两阶段递进式的SP(stated preference survey)调查方法,进行了大规模的世博客流出行方式选择意愿调查,多层次地分析了各种影响因素的效用;以此为基础,建立了描述本地、外地住宿、外地一日游等不同类型游客出行方式选择行为的多项Logit模型;利用这些出行方式离散选择模型,分析对比了多种交通管理措施和政策的组合场景实施效果,针对性地给出了世博交通管理的建议措施.     

复合电源蓄能修井机能量管理策略

针对网电修井机在使用时由于井场供电限制导致的变压器过载、井场短时停电以及下放作业能量浪费等问题,提出了以复合电源作为电动修井机的蓄能器,对修井机的输出功率进行补偿,并针对修井作业工况的特殊性,设计了一种基于局部优化的逻辑门限控制策略。利用MATLAB/Simulink建立主要部件仿真模型并对典型工况进行仿真。仿真结果表明,所设计控制策略能够对各动力源的能量进行合理分配,超级电容的高利用率能够更加充分地发挥其优势,降低蓄电池能量流通与功率输出幅值,延长了蓄电池使用寿命。     

河南油田注水地层异常压力理论研究

为了解决河南油田经过常年注水开发,使得地层压力发生变化,加上地层非均质性和复杂断层等方面的影响,地层压力变得更加错综复杂的问题。通过以渗流解析公式和油藏数值模拟两种手段为基础,研究了注水井泄压半径和地层异常压力分布规律,分别建立出注水井泄压半径理论图版。两图版相互验证,虽有一些差异,但趋势和结论均一致。结果表明:当地下注采比大于1时,无因次泄压半径均大于0.5,而且随着无因次波及面积的增大,无因次泄压半径逐渐增大。该图版不仅对河南油田高压区块的现场钻关井方案的合理制定提供了理论依据,对解决其他油田的类似问题也具有指导意义。     

拟波阻抗反演在葡北油田储层沉积微相刻画中的应用

 为了进一步提高碎屑岩油层沉积微相图的制图精度,并增强其横向预测性,以满足油气藏开发的需要,在大庆长垣葡北油田二断块,针对葡萄花油层中声波曲线不能有效区分储层与围岩,探索出了一套单井相与拟波阻抗地震反演数据结合沉积微相制图方法。该方法通过各种测井曲线储层敏感性交汇分析,找出储层敏感性测井曲线为自然电位曲线,并将其转换为阻抗值量纲的曲线,提取出高频部分,与原始波阻抗曲线低频部分合并,形成能反映储层变化的拟波阻抗曲线。然后,将重构拟波阻抗曲线用于地震反演。依据地震反演预测结果,分沉积单元精细调整拟波阻抗砂泥岩的门槛值,使阻抗体所反映的砂体厚度与测井解释砂体厚度纵向上具有最优的符合率,绘制各沉积单元砂岩厚度的平面分布。在绘制沉积微相图时,井点根据其单元所属的相带类型进行外推,井间微相由砂体厚度和形态确定,利用反演信息确定河道宽度,反演的波阻抗切片确定各沉积微相发育形态。最后,进行单井沉积相校正,完成各沉积单元沉积微相图。该方法强调单井相与地震拟波阻抗反演数据的结合预测沉积微相分布特征,实际应用效果表明新的制图方法精度高、实用性强,能有效推动油气藏精细开发调整。     

多模型油藏闭环管理

 针对目前基于单一模型进行油藏闭环管理的局限性,结合油藏数值模拟技术,提出了一种基于多模型实现的油藏闭环管理方法。利用集合卡尔曼滤波(EnKF)法通过拟合实测数据对地质模型进行实时更新,并以更新后模型的经济净现值的期望值作为目标函数,通过随机扰动近似算法(SPSA)进行油田生产优化。计算实例显示,应用该方法进行油藏闭环管理能够降低油藏模型的不确定性,给出更为合理的地质模型估计,所得控制方案相比常规方案明显改善了注水开发效果、提高了经济效益、降低了开发的风险性。     

Precipitation behaviors of X80 acicular ferrite pipeline steel

The precipitation behaviors of X80 acicular ferrite pipeline steel were investigated by using transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). The results show that dendritic precipitates in the as-cast steel slabs precipitate mainly in grain boundaries, and these dendritic precipitates dissolve and re-precipitate to two kinds of carbonitrides: Ti- and Nb-rich (Ti, Nb)(C, N) carbonitrides during reheating. Four types of precipitates mainly exist in the hot rolled plate: Ti-rich carbonitrides resulted from the dendritic carbonitrides undissolved during the reheating process; Ti-rich carbonitrides re-precipitated along austenite grain boundaries during the reheating process; NbC carbides mainly heterogeneously nucleated on the small pre-existing Nb-rich carbonitrides in the hot rolling process; and NbC carbides precipitated on dislocations during hot rolling.