从CIMT2007看齿轮加工机床的发展趋势

追踪、分析国内外齿轮加工机床的发展动态,总结其将向高精度、高速、高效、干切削、功能复合化、采用专用加工软件、采用新材料、采用先进的数控系统等方向发展。     

Carbon dioxide in the atmosphere-water system and biogenic elements in the littoral zone of Lake Baikal during period 2004–2018

We report long-term comprehensive measurements of CO₂ in the atmosphere, surface water and the major nutrients obtained for the period 2004–2018. The research was conducted at the Baikal Atmospheric and Limnological Observatory (BALO), which is located in the coastal zone of South Baikal (coordinates 51° 54′ N, 105° 05′ E). The seasonal variation of these characteristics was analyzed. For our site, during the open water period (May-December) we assessed average flux of CO₂, which amounted to −155 mmol m⁻² y⁻¹ (sink from the atmosphere to the water surface). Carbon dioxide content in the near-water air of Lake Baikal rises with a rate of 2.46 ppm per year, which is in good agreement with the global trend. The common effect of many factors (often multi-directional), such as variability of weather conditions, hydrological processes and productivity cycles of aquatic plankton in the Baikal waters, cause strong variations in the water characteristics, which we observed in different seasons and years. Under these conditions of strong inter-annual and seasonal variability of all characteristics, trend calculations using our long-term observations did not allow us to reveal reliable tendencies of changes in surface water CO₂ concentrations.     

ON THE ROBUSTNESS TO SMALL TRENDS OF ESTIMATION BASED ON THE SMOOTHED PERIODOGRAM

Abstract. In this paper we are concerned with the robustness of inferences, carried out on a stationary process contaminated by a small trend, to this departure from stationarity. It is shown that a smoothed periodogram approach to model fining and parameter estimation is highly robust to the presence of a small trend if the underlying stationary process is short-range dependent. If the underlying process is long-range dependent the robustness properties are still good but now depend on the Hurst index of the process and deteriorate with increasing Hurst index.     

冷轧晶粒取向硅钢的生产及市场动态分析

就国内外取向硅钢的生产、消费、市场占有情况作了简要介绍 ,并对国内外在取向硅钢产品产量、质量、品种及技术创新方面的差距作了简要分析。     

2018年网络空间国际治理回顾与展望

2018年网络空间国际治理进程仍旧处于缓滞状态。全球网络空间治理格局演变趋势总体上延续了自"斯诺登事件"以来的走向,即由"以美国为绝对主导的霸权"逐渐向"一超多强"格局转变。地缘政治因素与网络安全问题相互交织,导致国家间信任缺失现象进一步加剧,国家间竞争和博弈日趋激烈,主要表现为国家或区域性战略、规划或法规等治理举措频出,以及网络军备竞赛继续蔓延等方面。本文将围绕网络安全、数字经济、信息化与新技术、国际合作、国际规则制定五个重要领域展开分析。     

Assessing the effectiveness of disease awareness programs: Evidence from Google Trends data for the world awareness dates

Objectives

The process of disease awareness distribution on the web was studied. The contribution of WHO world awareness days to the total awareness process over the internet was investigated.

基于二次线性模型的网络舆情演化研究与实现

针对目前网络舆情形成迅速,对社会影响巨大,主要讨论在加强互联网信息监管的同时,研究网络舆情的演化趋势并研究相关算法以对其发展做出科学的预测,目的是对网络舆情的特性有一定的了解,掌握其基本的变化规律,以便提早采取应对措施,对于及时应对网络突发的公共事件和全面掌握社会民情民意有重大意义。     

数字化医院的建设与发展趋势的探究

数字化医院是现代化医院发展的必然趋势,也是构建和谐医院的重要组成部分。本文介绍了数字化医院的相关概念及特点,并对我国数字化医院的现状及数字化医院在建设中存在的管理不规范、信息人才缺乏等问题进行了初步探讨,最后结合数字化医院建设现状与发展情况,探究其未来的发展趋势。     

Lakes in the Finnish Eurowaternet: status and trends

The Eurowaternet is a monitoring network designed to cover all European countries, with the overall objective of obtaining timely, quantitative and comparative information on the status of inland waters so that their key environmental problems can be defined, quantified and monitored. Finland launched the Eurowaternet for lakes in 2000. The network was set up according to guidelines of the European Environment Agency (EEA) and was based on national, regional and local monitoring programmes. It includes 253 lake sites, divided into the following groups by, for example, their loading background and size: (i) reference sites, (ii) point-source loading (impact) sites, (iii) agricultural sites, (iv) representative sites, i.e. lakes <100 km(2) with typical water quality in the catchment and (v) lake deep sites in large lakes (>100 km(2)). We examined the water quality and its development during 1976-2001 in these groups, using data from surface and near-bottom water layers at summer and winter stagnation. In addition, the representativeness of the network was evaluated. Summer mean concentrations of total P (TP) during 1990-2001 in surface water were (i) 6.8+/-1.8 microg 1(-1) in reference lakes, (ii) 24+/-5 microg 1(-1) in lakes affected by point loading, (iii) 58+/-32 microg l(-1) in agricultural lakes, (iv) 14+/-2.2 microg l(-1) in representative lakes and (v) 11+/-2.1 microg l(-1) in large lakes. Comparison with reference lakes revealed major impact of human activities on TP and total N (TN)-and consequently on chlorophyll a (a-chl) and transparency-in all other groups, especially agricultural lakes. Decreasing TP and increasing O(2) trends were found at impact sites, reflecting water protection measures taken in pulp and paper mills and municipalities. More surprisingly, we found increasing alkalinity trends in all but agricultural sites and decreasing NO(2)-N+NO(3)-N (NO(x)-N) trends particularly in pelagic areas of large lakes. Comparison of water quality in Eurowaternet lakes with those in randomly sampled lakes (Finnish Lake Survey) revealed that the Eurowaternet covers the entire range of concentrations of TP, TN and conductivity in Finnish lakes, but <1-km(2), eutrophic and/or brown water lakes are underrepresented. Only 0.2% of a total of 13114 small lakes (0.1-1 km(2)) are included in the annual monitoring program of the Eurowaternet.     

Past, present and future intelligent reservoir characterization trends

As we approach the next millennium, and as our problems become too complex to rely only on one discipline to solve them more effectively, multi-disciplinary approaches in the petroleum industry become more of a necessity than professional curiosity. We will be forced to bring down the walls we have built around classical disciplines such as petroleum engineering, geology, geophysics and geochemistry, or at the very least, make them more permeable. Our data, methodologies and approaches to tackle problems will have to cut across various disciplines. As a result, today's “integration”, which is based on integration of results, will have to give way to a new form of integration, that is, integration of disciplines. In addition, to solve our complex problem, one needs to go beyond standard techniques and silicon hardware. The model needs to use several emerging methodologies and soft computing techniques: Expert Systems, Artificial Intelligence, Neural Network, Fuzzy Logic (GL), Genetic Algorithm (GA), Probabilistic Reasoning (PR), and Parallel Processing techniques. Soft computing differs from conventional (hard) computing in that, unlike hard computing, it is tolerant of imprecision, uncertainty, and partial truth. Soft Computing is also tractable, robust, efficient and inexpensive. In this paper, we reveal (explore) the role of Soft Computing techniques in intelligent reservoir characterization and exploration.