羰基合成法制取高纯纳米氧化铁工艺研究

纳米氧化铁是近年来研发的新型纳米材料,它具有良好的光学、磁性、催化性能,在涂料、磁性材料、医学磁介质和催化等方面有广泛的应用前景,采用传统技术生产的纳米氧化铁因其粒度分布宽,纯度低等问题无法用于生物医药等高端领域,本文通过实验的方法介绍了一种新型高纯纳米氧化铁生产技术,可为高纯纳米氧化铁的研究和生产提供参考。     

Recovering from demand disruptions on an air cargo network

In this work we introduce the Air Cargo Schedule Recovery Problem (ACSRP). In this problem, a carrier airline has to reschedule flights and requests to adapt to last-minute demand changes. We consider three different possible crew management policies that translate into three different way to evaluate the costs of deviating from the original schedule. We formulated the ACSRP as a mixed integer linear programming problem, and tested our implementation on 24 original schedules with up to 30 orders and 8 airports, and 4 different disruption scenarios for each one. Our results show that, against a benchmark recovery policy where only cargo is re-routed, recovery can yield savings of roughly 10%.     

Who is more important,parents or children? Economic and environmental factors and health insurance purchase

The existing research indicates that insurance demand is affected by the policyholder’s occupation, family economy, urbanization level, and insurance coverage. Using micro data of insurance purchase at the individual level, this study investigates the influence of economic and environmental factors on the priorities of health insurance purchase decision. The results reveal that the more developed the economy and the more financial knowledge people possess, the more the latter tend to prioritize health insurance for their children. Furthermore, the study investigates the influence of air pollution on the decision to purchase health insurance. If the air pollution level is high, policyholders prioritize obtaining insurance for their children. Our research on the order of insurance purchase indicates that Chinese families have a lack of support from their children, and the function of family pension is gradually weakening. Our research also reveals that families are willing to spend money on the insurance of their children. Therefore, to solve the problem of health and old-age security for the elderly, it is more effective to promote health insurance by considering families as a unit     

一种LAMBDA整周模糊度解算正确性的评估算法

针对基于经典假设检验理论的模糊度正确性评估算法的缺陷，提出了一种依据概率指标的LAMBDA（Least Square Ambiguity Decorrelation Adjustment）整周模糊度解算的正确性评估算法。该算法能够有效解决实时动态差分定位中模糊度解算值的可信度问题，降低系统完好性风险。通过对跑车实验中GPS差分定位数据的直接处理及引入多径误差后处理，该评估算法可以在置信水平为99.5%的条件下实时有效地评估模糊度解算值的正确性。     

Political Blue Sky: Evidence from the Local Annual “Two Sessions” in China

During politically sensitive periods, Chinese governments tend to take urgent administrative measures to control air pollution creating the temporary political blue sky. This empirical study uses the case of local "two sessions", one of the most politically sensitive periods in localities and examines the daily air quality index (AQI) as well as concentration data of air pollution components, including PM2.5, PM10, SO₂, CO, NO₂ and O₃ of 319 cities in China from November 2013 to June 2018. Results show that AQI decreases by approximately 4.5% during local "two sessions" periods compared to non- “two sessions” periods. Air quality improvements are mainly reflected in visible pollutants such as PM2.5, PM10 and SO₂. The mitigation of NO₂ and O₃, which is not observable by public, is not significant. In addition, the empirical results indicate that air quality deteriorates dramatically after the "two sessions". Therefore, the political blue sky comes with the price of catching up pollution that occurs after the political events.     

Controlling acid deposition: A general equilibrium assessment

In this paper, we evaluate the impact of the SO₂ provisions in the 1990 Clean Air Act. A computable general equilibrium (CGE) model of the United States is used to evaluate the implications of this law for a number of economic sectors. We find that the largest negative impact falls on the coal industry. Output in the refining sector also decreases, but agricultural production increases as consumers shift spending into food and wood based products.     

WiMAX技术的发展及其应用

网络营销过程管理分7个阶段:界定市场机会,制定营销战略,设计客户体验,构思客户界面,设计营销计划,分析客户信息和评估营销计划。车轮每转一圈,就会有一个或一批新的创新型网络运营商的出现。     

金鸡滩水利枢纽施工与通航措施探讨

文章论述了金鸡滩水利枢纽通过合理的枢纽总体布置和导流施工组织,有效地解决了施工期通航难题．减少了断航时间,其经验教训对同类型工程具有一定借鉴意义。