基于技术生态位结构特征的企业技术战略动态匹配研究

为了改善传统企业技术战略匹配的不足,在分析企业技术生态位与技术战略选择适应性基础上,运用双边匹配和多目标规划方法构建基于技术生态位结构特征(宽度和重叠度)的企业技术战略动态匹配模型,并以广州市萝岗开发区34家高新技术企业为例进行案例研究,通过Matlab软件编程求解得出34家企业应采用的技术战略.基于技术生态位结构特征的动态匹配模型可为企业技术战略选择提供一种更为宏观科学的方法.     

关中带高新技术供求的配套潜力与机制研究

在对陕西省关中高新技术产业开发带高新技术资源、生产潜力优势与企业对高新技术需求分析的基础上 ,本文研究了高新技术生产与需求相互配套的潜力、重点与具体方案 ,并建立了高新技术生产与需求的配套机制 ,提出了关中带配套机制运行中需要解决的主要问题与具体的对策。     

并联混合动力汽车动力源参数设计及模糊控制策略的建模仿真分析

根据汽车道路行驶的数学模型计算并联混合动力汽车驱动电机和发动机的各项参数,设计模糊控制策略控制驱动电机和发动机协调工作,使用Matllab/Simulink软件和Advisor汽车仿真软件联合建模仿真。在建模过程中,将上述计算结果输入Advisor汽车模型中,设置汽车的行驶工况、最高车速、加速时间和爬坡能力4个计算任务,并运行计算任务。仿真结果表明:汽车驱动电机和发动机的参数能匹配汽车整车参数、性能要求,模糊控制策略能在保证汽车整车性能要求的前提下进一步减少燃油消耗和尾气排放物,表明本驱动电机和发动机参数匹配设计方法、模糊控制策略均可行。     

The Development and Design of a Framework to Match Mentees and Mentors Through a Systematic Review andThematic Analysis of Mentoring Programs Between 2000 and 2015

ABSTRACT

The need for longitudinal and holistic support of medical students throughout their training has led to the development of formal mentoring programs. Whilst success of formal mentoring programs has been attributed to (a) pairing mentees with trained and experienced mentors (matching), (b) the quality of mentoring interactions and (c) the presence of a nurturing environment, little attention has been attributed to establishing an effective matching process in medical school. We sought, in this review, to redress this gap within the context of matching medical students for mentoring. Modified PRISMA guidelines were followed to guide the review process. PubMed, ERIC, Cochrane Database, OVID and ScienceDirect databases were searched for articles on matching in medical schools and in allied health specialities published between 2000 and 2015.     

基于直接寻找法的电阻抗断层成像

Solution to impedance distribution in electrical impedance tomography （EIT） is an ill-posed nonlinear inverse problem. It is especially difficult to reconstruct an EIT image in the center area of a measured object. Tikhonov regularization with some prior information is a sound regnlarization method for static electrical impedance tomography under the condition that some true impedance distribution information is known a priori. This paper presents a direct search method （DSM） as pretreatment of image reconstruction through which one not only can construct a regularization matrix which may locate in areas of impedance change, but also can obtain an initial impedance distribution more similar to the true impedance distribution, as well as better current modes which can better distinguish the initial distribution and the true distribution. Simulation results indicate that, by using DSM, resolution in the center area of the measured object can be improved significantly.     

博士后经历能给高校教师带来经济收益吗?

博士后制度具有培养和使用人才的双重属性,博士后经历既是人力资本投资亦是信号资本投资。基于2014年中国大学教师调查数据,运用倾向得分匹配法纠正样本自选择偏差后评估博士后经历的经济价值,研究发现:博士后经历具有显著的经济价值,拥有博士后经历的教师年收入比没有博士后经历的教师年收入高出11.40%。博士后经历的经济价值存在明显的异质性,"海归"博士后经历的经济效应是"本土"博士后经历经济效应的6.46倍。研究结论为未来青年博士职业发展路径选择、博士后管理制度改革与学术劳动力市场资源配置提供了实证依据。     

How Does Training Abroad Affect Faculty Income? An Analysis Based on the “2014 Faculty Survey in China”

Abstract

Training abroad is an important avenue for promoting the specialized development of faculty and improving international accomplishments. On the basis of the data from the 2014 Faculty Survey in China, this paper applies the technique of propensity score matching to control for the self-selection bias in the sample, so as to quantitatively evaluate the economic benefits of training abroad for faculty. The study finds that training abroad presents significant economic returns, while the potential benefits of training abroad for faculty members who have not yet pursued training abroad are higher than the benefits for faculty members who have pursued training abroad; a nonlinear relationship exists between the period of time for which a faculty member pursues training abroad and the economic benefits thereof, with the order of the economic benefits of training abroad from least to most for different time periods being: 1?year, less than one half year, more than one half year to less than 1?year, and more than 1?year. The conclusions of the study provide an empirical basis for the selection of pathways for the professional development of faculty in the future, as well as the design and refinement of training abroad programs, et cetera.     

Empirical Performance of Covariates in Education Observational Studies

This article summarizes results from 12 empirical evaluations of observational methods in education contexts. We look at the performance of three common covariate-types in observational studies where the outcome is a standardized reading or math test. They are: pretest measures, local geographic matching, and rich covariate sets with a strong theory of treatment selection. Overall, the review demonstrates that although the pretest often reduces bias in observational studies, it does not always eliminate it. Its performance depends on the pretest's correlation with treatment selection and the outcome, and whether preintervention trends are present. We also find that although local comparisons are prioritized for matching, its performance depends on whether comparable no-treatment cases are available. Otherwise, local comparisons may produce badly biased results. In cases where researchers have a strong theory of selection and rich covariate sets, observational methods perform well, but additional replication studies are needed. Finally, observational methods that rely on demographic covariates without a theory of selection rarely produce unbiased treatment effects. The article concludes by offering education researchers empirically based guidance on covariate selection in observational studies.     

心脏神经症患者的心功能特点

目的:探讨心脏神经症患者的心功能特点.方法:采用心阻抗法检测46例心脏神经症患者和50例健康成年人的心功能各项指标.结果:心脏神经症患者的SV、CO、CI、HI和AC均明显低于健康对照组(P＜0.01),而TPR明显高于对照组(P＜0.01),而且心脏神经症患者的心室舒张功能显著低于正常对照组.结论:心脏神经症患者的心脏收缩和舒张功能均减退.     

基于多级BP神经网络的EIT阻抗变化位置的确定

Electrical impedance tomography (EIT) is a new computer tomography technology, which reconstructs an impedance (resistivity, conductivity) distribution, or change of impedance, by making voltage and current measurements on the object's periphery. Image reconstruction in EIT is an ill-posed, non-linear inverse problem. A method for finding the place of impedance change in EIT is proposed in this paper, in which a multilevel BP neural network (MBPNN) is used to express the non-linear relation between the