科技与社会视野中的科学发展观

科学发展观的实质就是要处理好人与人、人与社会、人与自然的关系,构建和谐社会,促进人的全面发展.从科技与社会的互动关系看,科学发展观为科学全面进步提供了良好机遇,而实践科学发展观又对科学进步提出了新的要求,故实现科技进步与社会发展的良性互动,推进科教兴国战略是新世纪新阶段落实科学发展观的必然举措.     

Application of the BME approach to soil texture mapping

In order to derive accurate space/time maps of soil properties, soil scientists need tools that combine the usually scarce hard data sets with the more easily accessible soft data sets. In the field of modern geostatistics, the Bayesian maximum entropy (BME) approach provides new and powerful means for incorporating various forms of physical knowledge (including hard and soft data, soil classification charts, land cover data from satellite pictures, and digital elevation models) into the space/time mapping process. BME produces the complete probability distribution at each estimation point, thus allowing the calculation of elaborate statistics (even when the distribution is not Gaussian). It also offers a more rigorous and systematic method than kriging for integrating uncertain information into space/time mapping. In this work, BME is used to estimate the three textural fractions involved in a texture map. The first case study focuses on the estimation of the clay fraction, whereas the second one considers the three textural fractions (sand, silt and clay) simultaneously. The BME maps obtained are informative (important soil characteristics are identified, natural variations are well reproduced, etc.). Furthermore, in both case studies, the estimates obtained by BME were more accurate than the simple kriging (SK) estimates, thus offering a better picture of soil reality. In the multivariate case, classification error rate analysis in terms of BME performs considerably better than in terms of kriging. Analysis in terms of BME can offer valuable information to be used in sampling design, in optimizing the hard to soft data ratio, etc.     

水产养殖学特色专业建设的目标定位与建设路径

水产养殖学特色专业的建设是一项系统工程。首先,水产养殖学特色专业建设要正视在水产养殖业发展和水产养殖教育发展过程中出现的矛盾;其次,要为水产养殖学特色专业的建设确定适当的目标;第三,通过对原有教学理念进行创新,对办学模式进行重新构建,对师资队伍进行调整,对教学管理机制进行改革的建设路径实现上述目标。     

论泥石流学

泥石流学具有明确的研究对象、完整的学科体系和系统的研究方法，完全可以作为一门独立的学科；泥石流是一种复杂的山地灾害现象，研究难度大，研究历史又短，故泥石流学理论体系的成熟还需有个发展过程．泥石流学是一门正在趋向完善的新兴边缘学科．     

成矿作用动力学──理论体系和方法论

矿床是一种复杂系统，而成矿作用则是一种复杂的动力学过程。矿床成因的基本问题归根结底是成矿作用动力学问题。成矿作用动力学是地球化学过程动力学中的一个重要分支领域，又是矿床地球化学和矿床成因理论中的一个新的学术方向，但至今基本上还是一个有待开发的空白领域。成矿作用动力学研究成矿作用的速率、机制和过程。进行这一方面的研究不仅可以丰富地球化学过程动力学、发展理论地球化学，还可以使矿床成因研究从静态上升到动态，从定性走向定量，对传统的矿床成因理论将有新的突破。笔者在本文中根据自己的研究工作实践和对当前国内外地球化学过程动力学及非线性科学的发展现状和动态的分析与认识提出了成矿作用动力学的理论体系和方法论，并作了较详细的剖析。笔者还针对成矿地球化学系统的特点，强调指出将“多组成耦合系统和多重耦合过程动力学”作为成矿作用动力学的重点研究领域的必要性和重要意义。     

地球系统科学时代的区域地质调查应更加重视古生物资源调查

地球科学研究已进入地球系统科学时代,地球系统科学逐渐成为地球科学各分支学科重要的指导思想。本文论述了古生物资料在地质学诞生和发展中的重要作用及地球系统科学时代古生物资源调查的重要意义,分析了我国目前区域地质调查中存在的问题及其影响,对我国在区域地质调查中加强古生物资源调查提出了具体建议。     

Accurate Attribute Mapping from Volunteered Geographic Information: Issues of Volunteer Quantity and Quality

Crowdsourcing is a popular means of acquiring data, but the use of such data is limited by concerns with its quality. This is evident within cartography and geographical sciences more generally, with the quality of volunteered geographic information (VGI) recognized as a major challenge to address if the full potential of citizen sensing in mapping applications is to be realized. Here, a means to characterize the quality of volunteers, based only on the data they contribute, was used to explore issues connected with the quantity and quality of volunteers for attribute mapping. The focus was on data in the form of annotations or class labels provided by volunteers who visually interpreted an attribute, land cover, from a series of satellite sensor images. A latent class model was found to be able to provide accurate characterisations of the quality of volunteers in terms of the accuracy of their labelling, irrespective of the number of cases that they labelled. The accuracy with which a volunteer could be characterized tended to increase with the number of volunteers contributing but was typically good at all but small numbers of volunteers. Moreover, the ability to characterize volunteers in terms of the quality of their labelling could be used constructively. For example, volunteers could be ranked in terms of quality which could then be used to select a sub-set as input to a subsequent mapping task. This was particularly important as an identified subset of volunteers could undertake a task more accurately than when part of a larger group of volunteers. The results highlight that both the quantity and quality of volunteers need consideration and that the use of VGI may be enhanced through information on the quality of the volunteers derived entirely from the data provided without any additional information.     

考虑空间关系的极地科学数据本体表达与构建方法研究

两极是世界各国关注和研究的热点地区,极地科学数据量飞速增长,如何高效地管理极地科学数据并提供数据的智能服务,已成为极地数据库研究的重点。针对目前以关键词和主题词等字符匹配为核心的数据库查询中存在的查不全、查不准等问题,以中国南北极数据中心的元数据库作为数据源,引入本体论思想,提出了考虑空间关系的极地科学数据本体构建方法,研究了极地科学数据的语义概念、属性及语义关系,着重考虑了空间关系在本体构建中的形式化表示模型;设计了考虑空间关系的极地本体总体框架;最后,利用本体构建工具实现了极地科学数据本体库的搭建。考虑空间关系的极地科学数据本体库的建立对极地科学数据的精确发现和信息共享提供了有力的支撑。     

Search for TeV gamma-rays from Geminga pulsar

We present the results of observation of the Geminga pulsar carried out in the TeV energy band during the 6 year period spanning 2000–2006 using the Pachmarhi Array of Cherenkov Telescopes (PACT). A long stretch of data, new computer codes and the “Tempo” package have been used in the present analysis. We have searched for evidence of pulsed emission of γ-rays from the Geminga pulsar using the post-glitch pulsar elements obtained by Jackson and Halpern from X-ray/γ-ray satellite data. We do not see any significant evidence for pulsed emission from the Geminga pulsar at a threshold energy of 825 GeV. In this paper we present our results on the light curve in the TeV energy band, set an upper limit on the time averaged flux of γ-rays, and compare our results with other ground based observations.     

地球物理学的回顾与展望

简要回顾了 2 0世纪地球物理学的发展。指出 2 0世纪是地球物理学发展的重要历史阶段 ,在此期间实施的一系列大型的全球性的研究计划深化了人类对地球本体的认识 ,提供了有关资源、能源、灾害和环境的形成、分布与发展的深层过程和空间信息 ,扩大了人类对地球整体研究的视野 ,激励了对空间和地球 (包括大陆和海洋 )以及生态环境之间耦合的研究 ,并在造福人类的过程中取得了辉煌的成就。展望了 2 1世纪地球物理学的发展 ,认为 2 1世纪的地球物理学必将担负起地球科学中一系列重大科学问题的先导角色。在深化对地球本体和日地空间及其相互作用的认识 ,量化地球内部各圈的耦合和深部物质状态及物质组成的错综组构 ,解决水、资源、环境 (包括空间资源环境 )等问题中做出贡献。