汾河水库上游河流水环境风险评价

研究以满足太原市集中饮用水源地水质要求为前提,采用河流一维水质模型,模拟和定量评价了汾河水库上游突发性水环境污染事故风险。具体包括：识别污染事故风险危害,表征水环境危害大小,估算事故危害区范围以及危害期长短;最终定量评价了汾河上游水环境风险,为制定汾河上游水环境风险防范与控制对策提供了技术依据。     

Sequential batch sampling

Let {X_i} be i.i.d.{F_θ}.We consider the testing problem H₁θ<θ₀ vs H₂θ≥θ₀, where sampling is done sequentially in batches with variable batch sizes.For some parametric families {F_θ}, and under natural cost struc-ture, we characterize the Bayes procedures. This characterization of Bayes procedures lead to a similar characterization of essentially complete class of procedures.     

Esquentian of the mean by three stage procedure

Let X₁, X₂... be i.i.d. observations with mean μ and variance σ², and suppose that given a sample of size n one wishes to estimate μ by X_n, subject to the loss function L_n= A²(X_n-μ)²+n. When σ² is unknown, the optimal sample size n₀ for minimizing the risk R_n = E{L_n} cannotbe found. To resolve this problem, Robbins (1959) proposed a sequential procedure whenX_i is normally distributed, and then the asymptotic properties have been extensively studied. In this paper, we apply Hall's three stage procedure to the problem without specifying the distribution of X_i and derive the second order asymptotic expansions of the expected sample size and the risk.     

On uniform integrability and asymptotically risk-efficient sequential estimation

In the theory of asymptotically risk-efficient sequential estimation, one encounters uniform integrability of both positive and negative powers of stopping rules and moment convergence of randomly stopped statistics. We describe a simple approach to obtain these uniform integrability and moment convergence results, not only in the classical setting of i.i.d. observations but also for much more general stochastic sequences. We also use this approach to establish asymptotic risk efficiency of sequential estimators of means of stochastic sequences and to derive asymptotic approximations for the mean squared errors of ratio estimators.     

工程项目动态集成化风险管理模式的探讨

在工程项目全寿命周期风险管理和集成化风险管理的基础上,提出了工程项目动态集成化风险管理模式,即在工程项目所处的风险系统中,纵向上考虑风险集合、风险管理组织、风险管理过程及风险管理目标沿工程项目全寿命周期的动态变化,横向上考虑风险集合、风险管理组织、风险管理过程及风险管理目标的集成化,将工程项目风险管理的动态性和集成化统一起来,为工程项目风险管理的研究工作提供理论依据.     

先进压水堆大破口始发严重事故下安全壳内氢气风险分析

本文采用集总参数法,在先进非能动压水堆核电厂严重事故一体化分析模型基础上,考虑先进压水堆非能动安全特性以及严重事故下采取熔融物堆内滞留(IVR)措施等特性对氢气风险的影响,开展了典型严重事故下安全壳内氢气风险分析。分别选取了冷段双端剪切断裂大破口、冷段大破口叠加IRWST重力注水有效以及ADS-4误启动三个典型大破口失水事故序列,对事故进程中的氧化温度、产氢速率以及产氢质量等特性进行了研究。选取产氢量最大的冷段大破口叠加IRWST重力注水有效事故序列,分析了氢气点火器系统的消氢效果。结果表明,堆芯再淹没过程产生大量氢气,采用点火器可有效去除安全壳内的氢气,从而降低氢气燃爆风险。     

冲击危险性动态预测的震动波CT技术研究

针对煤矿冲击灾害日益频繁的现状,在应力与纵波波速的试验关系模型基础上,分析了采用纵波波速确定冲击危险的理论基础,建立了冲击危险性动态预测评价的震动波CT探测的技术,构建了震动波CT探测评价冲击危险性技术指标波速异常系数A n和波速梯度变化系数VG,并给出了各指标的判别准则,最后开展了现场应用。研究结果表明,对于同一性质的岩体,纵波波速反映了冲击矿压发生的强度条件、能量条件和动载诱冲条件;震动波CT探测技术能够对现场冲击危险性做出动态评价和预测,并能对卸压解危措施的实施和效果进行指导和检验。     

地勘单位转制后税务风险识别与控制

结合“减税降费”的政策背景,以陕西省某转制地勘单位为例,引入风险控制相关理论并应用层次分析法,构建了税务风险评估指标体系,对转制地勘单位面临的税务风险进行了识别、分析、评估。研究结果表明:针对不同的税收类型,应着重关注不同方面的风险,排序前6位的风险依次为企业所得税扣除类风险、增值税决策环节风险、增值税销售环节风险、房产税计税依据风险、企业所得税税收优惠类风险、增值税采购环节风险;并对上述风险的控制机制进行了分析,从企业管控、政策优化两方面分别提出了相关对策和建议。     

Riboflavin and health: A review of recent human research

There has lately been a renewed interest in Riboflavin owing to insight into its recognition as an essential component of cellular biochemistry. The knowledge of the mechanisms and regulation of intestinal absorption of riboflavin and its health implications has significantly been expanded in recent years. The purpose of this review is to provide an overview of the importance of riboflavin, its absorption and metabolism in health and diseased conditions, its deficiency and its association with various health diseases, and metabolic disorders. Efforts have been made to review the available information in literature on the relationship between riboflavin and various clinical abnormalities. The role of riboflavin has also been dealt in the prevention of a wide array of health diseases like migraine, anemia, cancer, hyperglycemia, hypertension, diabetes mellitus, and oxidative stress directly or indirectly. The riboflavin deficiency has profound effect on iron absorption, metabolism of tryptophan, mitochondrial dysfunction, gastrointestinal tract, brain dysfunction, and metabolism of other vitamins as well as is associated with skin disorders. Toxicological and photosensitizing properties of riboflavin make it suitable for biological use, such as virus inactivation, excellent photosensitizer, and promising adjuvant in chemo radiotherapy in cancer treatment. A number of recent studies have indicated and highlighted the cellular processes and biological effects associated with riboflavin supplementation in metabolic diseases. Overall, a deeper understanding of these emerging roles of riboflavin intake is essential to design better therapies for future.     

基于风险评价的重大火灾隐患判定方法

定义了广义和狭义的重大火灾隐患,分析了火灾隐患与火灾风险的关系。根据我国火灾统计数据,结合FN曲线和回归分析方法,确定了我国火灾社会可容忍风险及建筑重大火灾隐患判定标准。将所建立的方法应用于建筑重大火灾隐患工程评估中。运用事件树建立了具有代表性的火灾场景。运用FDS5.0火灾模拟软件和BuildingEXOUDS4.06疏散软件计算得到了各类火灾场景导致人员伤亡的量化结果。对某大厦判定结果显示,该单位存在重大火灾隐患。