技术战略管理中的两种关键因素分析--技术进步趋势与技术预测

技术战略是关系到企业能否把握机遇，在竞争中取胜的关键。我们重点分析了技术进步趋势以及技术预测在技术战略管理中的重要地位；提出只有在深入了解技术进步的趋势以及做出准确技术预测的情况下，才能进行有效的技术战略管理。     

Models of the formation of the solar nebula

Models of the collapse of a protostellar cloud and the formation of the solar nebula reveal that the size of the nebula produced will be the larger of $\text{R}{}_{\mathrm{<mtext>CF</mtext>}}\text{≡ J}{}^2\text{/k}{}^2\text{GM}{}^3\text{and}\text{R}{}_{\mathrm{<mtext>V</mtext>}}\text{≡ (GMv/2c}{}_{\mathrm{<mtext>c</mtext>}}{}^3\text{)}\text{1}\text{2}$ (where J, M, and c_s are the total angular momentum, total mass, and sound speed of the protosetellar material; G is the gravitational constant; k is a number of order unity; and v is the effective viscosity in the nebula). From this result it can be deduced that low-mass nebulas are produced if P ≡ (R_V/R_CF)² ? 1; “massive” nebulas result if P ? 1. Gravitational instabilities are expected to be important for the evolution of P ? 1 nebulas. The value of J distinguishes most current models of the solar nebula, since P ∝ J^?4. Analytic expressions for the surface density, nebular mass flux, and photospheric temperature distributions during the formation stage are presented for some simple models that illustrate the general properties of growing protostellar disks. It does not yet seem possible to rule out either P ? 1 or P < 1 for the solar nebula, but observed or possible heterogeneities in composition and angular-momentum orientation favor P < 1 models.     

东川泥石流站开放以来的回顾与展望

本文扼要介绍了中国科学院东川泥石流观测研究站对外开放三年来,在泥石流观测试验研究和防灾减灾工作中的新进展,同时也简述了站设基金课题、国家基金课题和中外合作交流项目的进展情况,并对今后的观测研究工作提出了展望和建议。     

资源环境系列制图研究的现实基础与发展

本文侧重于全国性资源环境及有关自然条件等专题制图工作的现实基础和成就,作简要总结和回顾。针对提高和重新认识制图效益和重点进行讨论,提出科学效益是基础,社会效益是目的,经济效益是根本,为资源环境的合理开发利用提供依据,并提出今后发展设想。     

南京大学的天文教育

全面介绍了南京大学天文系在各种教育水平 ,包括大学本科 ,硕士 ,博士和博士后教育的情况。     

A New Interpretation of Centimetre-scale Variations in the Progress of Infiltration-driven Metamorphic Reactions: Case Study of Carbonated Metaperidotite, Val d'Efra, Central Alps, Switzerland

Progress () of the infiltration-driven reaction, 4olivine +5CO₂ + H₂O = talc + 5magnesite, that occurred during Barrovianregional metamorphism, varies at the cm-scale by a factor of3·5 within an 3 m³ volume of rock. Mineral and stableisotope compositions record that X_CO2, ¹⁸O_fluid, and ¹³C_fluidwere uniform within error of measurement in the same rock volume.The conventional interpretation of small-scale variations in in terms of channelized fluid flow cannot explain the uniformityin fluid composition. Small-scale variations in resulted insteadbecause (a) reactant olivine was a solid solution, (b) initiallythere were small-scale variations in the amount and compositionof olivine, and (c) fluid composition was completely homogenizedover the same scale by diffusion–dispersion during infiltrationand subsequent reaction. Assuming isochemical reaction, spatialvariations in image variations in the (Mg + Fe)/Si of the parentrock rather than the geometry of metamorphic fluid flow. Ifinfiltration-driven reactions involve minerals fixed in composition,on the other hand, spatial variations in do directly imagefluid flow paths. The geometry of fluid flow can never be determinedfrom geochemical tracers over a distance smaller than the oneover which fluid composition is completely homogenized by diffusion–dispersion. KEY WORDS: Alpine Barrovian metamorphism; diffusion; metamorphic fluid composition; metamorphic fluid flow; reaction progress     

An evaluation of the Wellington Regional Genuine Progress Index

There is widespread discontent with the gross domestic product (GDP) as a measure of progress for society. Alternative measures have been proposed, including the genuine progress indicator (GPI). This paper examines the changing institutional arrangements and attitudinal context in the recently developed Wellington region (New Zealand) GPI. We found an alignment between the GPI framework and the Local Government Act. Despite this fit, we identified challenges, including the need to revitalise public participation through deliberative techniques. It remains too early to judge whether the GPI initiative will launch a viable alternative to the GDP for the Wellington region.     

城市热岛效应的研究进展与展望

随着世界各国城市化的进展,城市热岛效应已经成为一个跨学科领域的问题,受到包括大气环境、区域气候、水文和生态等多学科科学家的关注。在过去半个多世纪中,城市热岛问题的研究获得了相当丰富的研究成果,通过对这些成果的综合分析,归纳出城市热岛研究中采用的3类主要方法——观测(外场试验和遥感技术)、数值模拟以及实验室仿真法。系统地回顾了城市热岛效应的研究历史,重点对与城市热岛关系最密切的城市边界层、热岛环流与复杂地形的相互作用以及能量平衡研究所取得的成果进行了总结和评述。最后对城市热岛问题未来8个可能的研究方向进行了探讨,其中,包括沿海和复杂地形附近的城市热岛问题、城市群间热岛环流的相互作用、城市化与空气污染问题、城市热岛效应对平均降水的影响、城市化对雾和闪电的影响、城市天气预报的精细化、城市气候变化预测以及城市热岛效应减缓方案的制定,并对其发展前景进行了粗略的展望。     

下垫面对WRF模式模拟黑河流域区域气候精度影响研究

利用高精度的土地覆盖、土壤质地类型和地形高度值替换了天气研究和预报模式Weather Research and Forecasting Model(WRF)中的相关数据,通过数值模式试验检验了下垫面数据对WRF模拟精度的影响。同时,通过与黑河综合遥感联合试验中7个测站观测数据的比较,以平均误差、均方根误差和相关系数为指标,分析了WRF模式下垫面数据改变对近地表气象要素的模拟精度的影响。结果表明:(1)WRF模式本身的地形高度信息在黑河流域上游地区有较大误差,造成了一定的模拟误差。而使用高精度的下垫面数据可以提高WRF模式在黑河流域上游复杂区域的模拟能力;(2)2m气温除了随地形高度递减外,还受土壤质地和土地覆盖小幅度影响,而且进行地形订正后的2m气温与2m湿度的模拟在下垫面为水体的区域对比强烈,因此为模式提供准确的水体分布信息也至关重要;(3)2m气温和湿度等要素的模拟差异值与地形高度资料的差异呈负相关,而降雨量的差异与地形高度差异呈微弱的正相关,与土壤质地差异和土地覆盖差异的相关性也比较弱。     

近50a华北暴雨研究主要进展

在我国加快实现气象业务现代化进程及2012年7月21日北京出现特大暴雨洪涝灾害的背景下,较为系统地回顾总结了近50 a华北暴雨的主要研究进展,其内容涉及大尺度环流形势及其分型、中低纬度系统相互作用、水汽输送、高低空急流、直接造成暴雨的中尺度系统、复杂地形以及下垫面、气候学特征等诸多方面。对这些研究成果的梳理,旨在加深对华北暴雨的理解和认识,加强华北暴雨研究,提高华北暴雨的预报水平。提出在继续开展大尺度系统发展演变研究的同时,有必要借助新型观测和数值模拟手段,有针对性地开展华北暴雨β（γ）中尺度系统细致研究,以期更清楚地揭示华北暴雨中尺度系统的三维结构特征、发生发展机理。