应用全分布分解法研究卫生支出增长

有关卫生支出增长的解释将人们的注意力限制在一般原因上。该文通过对卫生支出分配的分析,洞察卫生支出增长的原因,以及分布不同对卫生支出影响的解释。该文分析了荷兰人实际卫生支出的数据,这些数据与出院登记、死亡登记相关。如果仅仅观察支出平均水平的改变,那么全分布分解所提供的资金将可能被忽略。处于中间分布的地区,其卫生支出的增长速率最显著,而造成这一现象的主要原因是影响分布的决定性因素发生了改变。医药支出增长的速度在上层分布中最迅速,这主要归因于医疗结构的变化。譬如,先进医疗技术的引进和应用,使得高成本的治疗变得更加昂贵。医疗行为方式的改变是导致卫生支出增加的决定性因素,表现出显著的溢出效应。

收入差异分布分解方法比较

针对收入差异分解的方法可分为均值分解和分布分解两大类,相对于均值分解,分布分解可以将收入水平划分为不同的层次,并分别对各个收入层次的差距状况及其原因进行细致的描述和刻画。在收入差距日益扩大的今天,分布分解方法具有更加明显和独到的优势。而在分布分解中,基于条件分位数回归的MM2005分解、Melly(2005)分解、Melly(2006)分解、Q-JMP分解在现阶段使用相对广泛,文章运用同一数据对这四种条件分布分解方法的结果进行比较研究,分析它们之间的内在联系和各自的特点,为研究者选择合适的分解方法提供一定的参考。

样本选择参数分位回归模型及其在工资分布分解中的应用

在工资差距分解问题中,研究者经常会遇到样本选择偏差问题,直接忽略会导致最终估计结果产生严重偏差,同时在众多工资差距分解方法中,相比于均值分解,分布分解方法更受研究者青睐。针对参数分位回归,本文首次提出可加形式与非可加形式的样本选择参数分位回归(SSPQR)模型,并基于这两类样本选择参数分位回归模型给出修正样本选择偏差后的参数分位回归工资差距分布分解方法。运用上述方法及已有的工资分布分解方法,借助CHNS2015年度城镇数据,本文研究了我国城镇男女工资差距及差距分解问题,得出以下结论:①男女工资差距主要来源是性别歧视问题;②经过样本选择偏差修正后,实际的工资差距更大,歧视问题更严重;③男女工资差距程度在不同分位点上结果不同,换句话说,我们不能简单地仅从平均水平来判断工资差距程度;④与其他已有方法计算结果比较发现,SSPQR计算的工资差距程度更大。

我国城镇居民收入不平等变动实证研究——基于收入分布变化分解的视角

对收入不平等变动研究,目前多数基于对不平等指标的分解,计算结果会因收入数据分组的不同而产生较大差异。本文基于收入分布变化分解的视角,对我国地级市以上城镇居民收入不平等变动进行了实证分析。研究结果表明,收入分布位置变化对于收入分布变化的影响最大,而收入分布形状变化却在一定程度上抵消了这种影响效果,收入分布的其他变化虽有影响,但程度相对较低。收入分布位置变化有助于缓解不平等程度的加剧,而收入分布形状变化则加速不平等程度的恶化,其影响程度对于不同的收入阶层有所不同。本文认为,经济增长是缓解收入不平等恶化的主要原因,而收入分配的改变却在一定程度上加剧了收入不平等。

运用分布函数分解求随机变量数学期望

将一般的分布函数分解成连续部分和离散部分,再根据Stieltjes积分的性质,成功地计算出一般的混合型随机变量的数学期望.该方法对通常的离散性或连续型随机变量数学期望的计算同样适用.

椭球等高分布族中下三角分解的一些结果

该文证明了正定阵下三角分解存在且唯一的结论,运用外微分的方法给出该分解的Jacobian,再分别得到Wishart分布、矩阵Beta分布、逆矩阵Beta分布和矩阵F分布的下三角分解的相应结果。

集合风险模型的可分解性

本文讨论了集合风险模型中 ,在复合二项分布和复合负二项分布两种情况下的可分解性问题 。

组合信用损失分布的蒙特卡洛模拟

组合损失分布的确定是测量各种组合信用风险的一个先决条件.本文通过对信用风险损失理论进行分析的基础上,分析阐述了利用蒙特卡罗方法模拟组合信用损失的原理和方法,并基于Matlab语言结合实际问题进行仿真实验,实验结果表明该模拟方法能较好地反映组合信用损失的分布特征,具有有效性和实用性.

分布式用户隐私保护可调节的云服务个性化QoS预测模型

个性化服务质量(Qo S,quality of service)预测是构建高质量云服务系统的重要环节,传统基于协同过滤方法采用集中式的训练模式难以保护用户隐私,为了在获取高准确预测效果的同时有效保护用户隐私,提出分布式用户隐私保护可调节的云服务个性化QoS预测模型(DUPPA)。该模型采用“服务器-多用户”架构,服务器协调多个用户,处理多用户上传模型梯度和下载全局模型的请求并维护全局模型参数。为进一步保护用户隐私,提出用户隐私程度调节策略,通过调节本地模型参数初始化比例、梯度上传比例以平衡隐私程度和预测精度。在本地模型初始化阶段,用户计算本地模型与全局模型的差值矩阵,并选择差值矩阵中数值较大元素所对应的全局模型参数初始化本地模型参数;在梯度上传阶段,用户可选择部分重要的梯度上传至服务器来满足不同应用场景对隐私保护的需求。为了评估DUPPA的隐私程度,提出针对分布式矩阵分解模型梯度共享方案的数据重构攻击方法。实验结果表明,当DUPPA在梯度上传比例为0.1、本地模型参数初始化比例为0.5时,预测的平均绝对误差(MAE,mean absolute error)和均方根误差(RMSE,root mean square error)较传统的集中式矩阵分解模型分别降低了1.20%和0.91%;当DUPPA的梯度上传比例为0.1时,隐私程度至少是梯度上传比例为1时的5倍;当DUPPA的本地模型参数初始化比例为0.5时,隐私程度至少是本地模型参数初始化比例为1时的3.44倍。

基于推广的概率分布区间分解法的时滞系统稳定性分析

基于推广的概率分布区间分解法,研究一类具有随机时滞系统的概率分布相关稳定性问题.充分利用随机时滞的概率分布信息,获得一系列稳定性判据;通过严格的数学证明,表明通过增加概率区间数可以逐渐降低稳定性判据的保守性,从而建立一组新的分层结构LMI条件;严格证明了在采用相同概率区间划分的条件下,所得到的稳定性判据的保守性低于不考虑时滞概率分布的时变时滞分解法所得到的结果,并且分析和比较了两种方法的计算量.

Gravity inversion using the frequency characteristics of the density distribution

Three-dimensional gravity inversion based on the mass property model is very popular in recent years. The time and efficiency of inversion algorithms is relative to the magnitude of the target mesh. One approach is to search over the entire solution space for a more refined result. However, the inversion will be difficult with the increased parameters in the large search space and the number of computations increases exponentially. ｜n this paper, we propose a novel approach based on the frequency characteristics of the density distribution over the mesh. The purposes of our study are to reduce the parameters of three- dimensional gravity inversion and to lighten the image quality of the inversion result. The results show that the new method can expedite the inversion processing and get a better geological interpretation than tradition methods.

中国垄断行业与非垄断行业收入决定机制差异

本文采用中国健康与养老追踪调查(CHARLS)数据,从均值收入和分布收入角度考察垄断行业和非垄断行业收入决定机制的差异。研究结果表明:垄断行业并不具有特征优势,垄断行业与非垄断行业间的收入差距主要由特征回报差异所决定;市场机制在非垄断行业发挥了更大的作用,而垄断行业的收入决定机制则更具"共享式"的特征;性别和地区差异对垄断行业的收入起到抑制作用,垄断行业过度的"论资排辈"拉高了工资分布高端的工资溢价;对垄断行业的收入规制,对象应是工资分布高端人群,措施应是减少论资排辈而实施更具激励性的工资决定机制。

Analysis of Molecular Weight Distribution and Antioxidant Activities of Cirrhinus molitorella Skin Collagen Hydrolysates

[Objective] The aim of this work was to identify molecular weight （MW） distribution and antioxidant activity of fish skin col agen hydrolysates. [Method] The MW distribution of hydrolysates was determined using both size exclusion chromatography and matrix-assisted laser desorption ionization time-of-flight mass spec-trometry （MALDI-TOF-MS）. Fish skin were treated by the alkaline protease 2709. [Result] The optional conditions for hyerolysis were time 3 h, temperature 55 ℃, pH 10.0, substrate concentration 80 g/L and E/S 4%. The results of both methods indi-cated that the molecular weight of col agen hydrolysates was from 400 to 1 800 Da, and the peptides’ molecular weight was less than 1 400 Da mostly. The reducing power and antioxidant/radical scavenging activity [1, 1-diphenyl-2-picryl-hydrazyl （DPPH） free radical scavenging activity] were determined. [Conclusion] The results reveal that the fishskin hydrolysate is a potential source of antioxidants.

The Distribution of Dissolved Aluminum in the Yellow and East China Seas

Water samples containing dissolved aluminum were collected from the Yellow and East China Seas in October-November 2000. The average concentrations of dissolved AI in the Yellow Sea （YS） and East China Sea （ECS） were 0.042 and 0.056 μ molL^-1, respectively. The concentration of dissolved aluminum decreased gradually across the continental shelf. The lower concentrations appeared in the YS cold water center and in the bottom layer at the shelf edge of the ECS, where they were 0.016 and 0.011 μmolL^-1, respectively. The distribution of dissolved Al was controlled by physical mixing processes rather than biological uptake processes. The impact of different water masses along the PN transect was calculated based on the mass balance model. The results show that the impact of the Changjiang River was mainly concentrated on the coastal area and the top thermocline water on the ECS shelf, where the impact percentage decreased from 12.6% to 1.1% in the surface water, while the contribution of the Kuroshio water was dominant on the ECS shelf in this survey, increasing from 77.6% to 97,8% along the PN transect from the Changjiang River Estuary to the Ryukyu Islands. It is concluded that aluminum can serve as a proper tracer for studying the impact of Changjiang terrestrial matter on the ECS shelf water.

A New Study on Combustion Behavior of Pine Sawdust Characterized by the Weibull Distribution

An isothermal operation is implemented by employing a thermogravimetric analyzer (TGA) for simulating the thermal decomposition behavior of 58μm pine sawdust in air atmosphere.An independent parallel reaction model is adopted in this study to describe the thermal decomposition mechanism.The Weibull distribution function is used to record and analyze the weight loss during isothermal decomposition at different temperatures(500,600,700,and 800°C).The total weight loss of the pine sawdust is assumed as a linear combination of individual weight loss from three components,including the char and two volatile matters.The plot of the thermal decomposition rate curve leads to kinetic parameters such as the reaction rate constants and the reaction order.The results show that the Weibull distribution function successfully represents decomposition curves of three components,and fits the experimental data very well.Therefore,this study provides a simple way to evaluate the decomposition rate of biomass combustion in a real combustor.

Kinetics of Chlorine Decay in Water Distribution Systems

A combined first and second-order model, which includes bulk decay and wall decay, was developed to describe chlorine decay in water distribution systems. In the model the bulk decay has complex relationships with total organic carbon (TOC), the initial chlorine concentration and the temperature. Except for the initial stages they can be simplified into a linear increase with TOC, a linear decrease with initial chlorine concentration and an exponential relationship with the temperature. The model also explains why chlorine decays rapidly in the initial stages. The parameters of model are determined by deriving the best fitness with experimental data. And the accuracy of model has been verified by using the experimental data and the monitoring data in a distribution system.

基于VMD-WVD相位法的长电缆局放双端定位

快速准确定位电缆局放故障位置对电缆系统安全稳定运行具有重要意义。针对传统行波定位法在长电缆局放定位时反射信号难以识别以及存在时间同步误差的问题,提出一种基于变分模态分解-维格纳威尔分布(VMD-WVD)相位法的电缆局放双端定位方法,通过准确标记双端局放信号波头时刻实现双端局放信号的同步,利用相位定位实现长电缆局放入射信号的双端同步。文中建立了长线路PSCAD模型,分析故障位置、电缆长度和采样率对VMD-WVD相位法在长电缆定位的精度影响。结果表明,在上述3种因素影响下,VMD-WVD相位法的平均定位精度分别为0.54%,0.85%,0.69%,高于传统行波定位法。文中研究成果为长电缆局部放电精准定位提供一种全新思路。

Straw ^(14)C Decomposition and Distribution in Humus Fractions as Influenced by Soil Moisture Regimes

14C-tracer technique and closed incubation method were used to study straw 14C decomposition and distribution in different fractions of newly formed humus under different moisture regimes. Decomposition of straw 14C was faster during the initial days, and slower thereafter. Decay rate constants of straw 14C varied from 3.29x10-3 d-1 to 7.06x10-3 d-1. After 112 d incubation, the amount of straw 14C mineralized was 1.17～1.46 times greater in submerged soils than in upland soils. of the soil residual 14C, 9.08%～15.73%was present in humic acid (HA) and 31.01%～37.62% in fulvic acid (FA). Submerged condition favored the formation of HA, and HA/FA ratio of newly formed humus (labelled) was greater in submerged soils than in upland soils. Clay minerals affected the distribution of straw 14C in different humus fractions. Proportion of 14C present in HA to 14C remaining in soil was greater in Vertisol than in Ultisol.

Distributed Chunk-Based Optimization for MultiCarrier Ultra-Dense Networks

In this paper,a distributed chunkbased optimization algorithm is proposed for the resource allocation in broadband ultra-dense small cell networks.Based on the proposed algorithm,the power and subcarrier allocation problems are jointly optimized.In order to make the resource allocation suitable for large scale networks,the optimization problem is decomposed first based on an effective decomposition algorithm named optimal condition decomposition(OCD) algorithm.Furthermore,aiming at reducing implementation complexity,the subcarriers are divided into chunks and are allocated chunk by chunk.The simulation results show that the proposed algorithm achieves more superior performance than uniform power allocation scheme and Lagrange relaxation method,and then the proposed algorithm can strike a balance between the complexity and performance of the multi-carrier Ultra-Dense Networks.

Temporal Variations of Water Discharge and Sediment Load of Huanghe River,China

Based on the data from gauging stations, the changes in water discharge and sediment load of the Huanghe （Yellow） River were analyzed by using the empirical mode decomposition （EMD） method. The results show that the periodic oscillation of water discharge and sediment load of the Huanghe River occurs at the interannual, decadal, and multi-decadal scales, caused by the periodic oscillations of precipitation, and E1 Nifio/Southern Oscillation （ENSO） af- fects water discharge by influencing precipitation distribution and contributes to periodic varations in precipitation and water discharge at interannual timescale. The water discharge and sediment load of the Huanghe River have decreased since the 1960s under the influence of precipitation and huamn activities, and human activities attribute more than precipitation to the reduction in the water discharge and sediment load, furthermore, water abstraction and water-soil conservation practices are the main causes of the decrease in water discharge and sediment load, respectively. The reduction in sediment load has directly impacted on the lower reaches of the Huanghe River and the river delta, causing considerable erosion of the river channel in the lower reaches since the 1970s along with River Delta changing siltation into erosion around 2000.