21世纪我国热电联产集中供热的展望

本文从中国实际出发,对热电联产,集中和分散供热的各种技术进行了讨论,提出了看法,认为21世纪供热系统更加多样化,但上半世纪仍将以大型热电联产为主。     

不同所有制企业创新主体地位评价 ——规模与效率双重视角的研究

推动企业成为创新决策、研发投入、科研组织和成果应用的主体,是实施创新驱动发展战略的关键。针对企业创新主体地位较难衡量且缺乏考虑企业创新效率的问题,从规模视角入手,基于创新价值链分析,通过区分企业所有制性质,研究企业创新主体地位评价指标体系和评价方法。同时,结合BCC-DEA模型和DEA-Malmquist指数,从创新效率角度系统探讨企业创新主体地位。以上海为例的实证结果表明,上海企业在研发投入端的创新主体地位相对突出,但呈不断弱化趋势,尤其是R&D经费增长显著落后于科研机构和高等院校;在以发明专利为代表的产出端,企业创新主体地位尚不明显,且同样存在比重下滑迹象。外资企业年度创新效率表现最优,内资企业处于明显劣势,但得益于技术效率增长,科技创新全要素生产率保持年均微幅增长,而港澳台商投资企业创新效率存在递减态势。最后提出加强科技资源配置、挖掘科技产出、加大科技成果转化力度等建议。     

塔里木油田哈得区块标准井及标准井标准工艺流程的构建

为缩短钻井周期、节约钻井成本,塔北项目部率先提出了以标准井及标准工艺流程为经度,以标准化设计、标准化安全管理、标准化工期及费用、标准化质量控制及考核机制为纬度的"五标"管理理念,而标准井及标准工艺流程为构建"五标"管理理念的关键。根据对哈得区块已完钻的直井、水平井、侧钻井、定向井的统计分析,并结合实际生产开发情况,确定了以直井和水平井作为哈得区块标准井的井型;根据标准井产层的各项地层参数,确定了相应标准井的钻头尺寸组合、钻进深度、套管规格、套管下深、泥浆体系、测井等参数,从而构建了哈得区块直井和水平井2种井型的标准井;同时依据各标准井构建了相应标准井的标准工艺流程。通过塔北项目部的生产实践表明,标准井及标准井的标准工艺流程的构建大大有助于提高油田的经济效益和管理效率。     

高职专业课程分层教学模式的研究与实践

目前高职生源已呈多样化,学生的基础知识、学习能力参差不齐,同时,学生的兴趣爱好、学习毅力和心理素质等非智力因素也存在较大的差异,传统的、单一的教学模式已不能取得较好的学习效果.为提高高职人才的培养质量,该文结合高职专业课程的教学,提出了分层教学的模式和方法,并在分层教学中,融入思政教育,形成协同效应,取得了很好的效果.     

广甘高速公路边坡安全监测实践与思考

本文结合四川广甘高速公路边坡安全监测实践,对边坡安全监测技术的发展过程与前景进行了认真的思考与分析。     

Likelihood evaluation of models with occasionally binding constraints

Applied researchers interested in estimating key parameters of dynamic stochastic general equilibrium models face an array of choices regarding numerical solution and estimation methods. We focus on the likelihood evaluation of models with occasionally binding constraints. We document how solution approximation errors and likelihood misspecification, related to the treatment of measurement errors, can interact and compound each other.     

The capital market spillover effect of product market advertising: Evidence from stock price synchronicity

We analyze whether product market advertising has a spillover effect on stock price synchronicity by transmitting firm-specific information to the capital market and attracting more investor attention. Using a sample of Chinese listed firms from 2009 to 2017, we find that firms with greater advertising expenditures have lower stock price synchronicity. The results are robust after we address endogeneity concerns. In accord with our hypothesis that product market advertising increases the amount of firm-level information capitalized into stock prices through the information channel, we find that the impact of advertising on synchronicity is more pronounced for firms with a higher degree of information asymmetry and firms in the consumer-product industry. Further tests show that product market advertising enhances the ability of current period returns to reflect future earnings, and thus rules out that the negative relationship between advertising and synchronicity is driven by noise trading. Our results imply that product market advertising plays an informative role and improves information efficiency in a capital market.     

Immigrants’ net direct fiscal contribution: How does it change over their lifetime?

Life-cycle direct public fiscal contributions and transfers are studied using longitudinal income tax data from 1982 to 2016 and administrative files for immigrants landed in Canada from 1980 to 2016. Relative to a comparison group comprising the Canadian-born and immigrants landed before 1980, immigrants since 1980 have a lower average net direct fiscal contribution (NDFC) during their working years due to their lower taxes and social security contributions but a higher average NDFC after 65 years of age because of reduced public pension eligibility and entitlement. Immigrants who landed at younger than 19 years old have much higher direct fiscal contributions than other age-at-arrival groups and reach their peak of contributions around 10 years earlier in life than other age-at-arrival groups. Immigrants whose age at arrival is above 65 have a less negative average NDFC than other age-at-arrival groups over the above-65 life cycle. These life-cycle age𠄁at-arrival trajectories are stable for immigrants in different landing cohorts. We apply the life-cycle estimates to project the present discounted value of lifetime NDFCs for immigrants who landed in 2016. For each landing age group, refugees and family class immigrants have negative or zero average present values of life-cycle NDFCs, much below that of economic immigrants.     

刺芪参胶囊的制备工艺研究

目的:探索刺芪参胶囊的制备工艺。方法:采用正交实验,以总皂苷质量为指标,优化提取工艺;采用单因素实验优化制剂工艺。结果:在最佳提取工艺条件下,刺芪参胶囊提取物中的总皂苷含量为12.19 mg·g-1;以糊精作为填充剂、硬脂酸镁为助流剂、95%乙醇为黏合剂制备胶囊剂。结论:刺芪参胶囊的制备工艺稳定可行。