中国区域经济与环境协调度预测分析

经济发展与环境之间的关系已经成为全世界特别是发展中国家关心的问题，但有关的定量研究比较缺乏。该文首先解释了经济与环境协调度基本概念与模型内涵，并介绍了灰色系统在贫信息系统中进行预测的基本原理。通过灰色系统GM(1,1)模型对90年代我国省级区域的经济与环境协调度进行了计算，经过检验，模型模拟精度较高。因此运用此模型对2005年与2010年的区域协调度进行了预测。结果表明，我国大部分地区的经济与环境关系基本处于调和状态，即经济的增长是以牺牲环境为代价的。未来10a的协调度空间分布仍然呈现“U”型特征。处于转折点附近的省区协调度波动比较大，包括广大的中部地区。尽量减少波动并尽快实现协调度的转折是这些地区在经济发展过程中要注意的问题；西部大部分地区如果继续沿用90年代的发展策略，对经济发展政策和手段不作宏观的调控，在西部开发过程中出现的环境问题将会越来越严重。     

生态因子对礁膜配子放散及黑暗时间对合子固着的影响

采用单因子实验方法研究了湛江港礁膜配子的成熟放散与温度、光照、比重和pH值的关系,并对黑暗时间对配子接合及合子附着的影响进行了初步研究。实验结果表明,在温度为20℃、光照强度为80．13μmol/（m^2·s）左右、pH值为7．9、比重为1．018的室内培养条件下,为礁膜配子体成熟和配子囊大量放散配子的最适宜生态条件。早期合子附着的适宜黑暗时间为5—6h。     

在Linux下开发个人防火墙软件

从网络安全的实际需要出发 ,阐述了用Linux开发个人防火墙的思想、方法和注意事项 ,并给出了具体的设计实例 .     

劳动力市场分割与大学毕业生失业

具有大学以上学历者占我国全部劳动者的比例非常低 ,但最近几年大学毕业生找工作却有越来越难的趋势。这种看似矛盾的现象是转型过程中劳动力市场分割这一制度背景下 ,大学毕业生与用人单位相互搜寻的结果。过大的城乡收入差距和过高的工作转换成本 ,使大学毕业生“宁要城里一张床 ,不要农村一幢房”,但城里的用人单位却因过高的解聘成本和户口成本而不能吸收更多的大学毕业生。因此 ,大学毕业生就业难的缓解和解决 ,要依赖经济发展 ,也离不开体制改革     

A methodology for the identification of glass panes of different origin in a single stained glass window: Application on two 13th century windows

The chemical composition of 11 glass panes originating from two 13th century non-figurative windows were analyzed by means of Scanning Electron Microscopy–Energy Dispersive X-ray system (SEM-EDX). The windows were discovered in the back-wall of the triforium during the restoration of the choir of the cathedral St. Michael and St. Gudule in Brussels (Belgium). In order to determine if these windows were fabricated with glass of different origin or not, the compositional difference between the panes were compared with the variation in composition as a result of the following causes: (1) compositional fluctuation between panes cut from the same sheet of glass, (2) compositional fluctuation caused when panes are cut from different sheets that were made with the same batch, (3) compositional fluctuation caused when the glass is made from different batches at the same production center, and (4) compositional fluctuation as a result of glass produced at different fabrication centers.     

Optimal sampling frequency in recording of resistance training exercises

The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f_99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality.