遗产廊道的深刻鉴别与再发现--日本线性历史景观研究中的历史地理学先发探查与解析

景观考古学的前期探查需求,及其与风景园林、古建筑学等相关学科的学际综合研究的发展,对中国历史地理学的研究提出新的要求。现代日本史地学者对于古驿道系统、历史性街道系统等遗产廊道的深刻鉴别及创造性的再发现表明:基于历史背景考察、文献记录核检、大比例尺地图与现场实勘比定等复合分析的历史地理学先发探查与解析方法,对于此类线性景观的历史演变与复原研究来说是一种既具研究效率、又不可或缺的分析手段,对中国开展景观考古研究与大遗址保护也深具启发意义。

洪涝灾害研究主题的时空差异性:中英文文献比较研究

在全球气候变化背景下,洪涝灾害已成为威胁人群生命财产安全的世界性问题。目前,关于洪涝灾害的研究已较为丰富,需进行系统性梳理和总结。为探究国内外洪涝灾害的研究现状与趋势,采用文献计量的分析方法,对2003—2022年中国知网(China National Knowledge Infrastructure,CNKI)和WoS(Web of Science)数据库中主题为洪涝灾害的中英文文献进行文本分析。从关键词共现模式、研究主题的时间聚类及空间分布三个角度,探索洪涝灾害相关研究的主题演进模式和地理分布特征,并总结未来发展方向。结果表明:(1)在研究关键词共现模式方面,中文研究更加关心洪涝灾害区域影响及管理策略等灾害的后续影响方面,英文研究则更倾向于探究洪涝灾害的成因,从气候变化与孕灾环境角度分析洪涝灾害。中英文研究均强调新兴技术在洪涝灾害研究中的应用。(2)在研究主题时间聚类方面,中文研究在21世纪初期追随英文研究的关注热点,并在2015年前后逐渐形成具有中国本土化特色的研究框架,强调使用多源数据和多种算法模型进行定量化分析,主要着眼于城市化发展对洪涝灾害的多时段、多尺度干预效应。(3)在研究主题空间分布方面,沿海经济发达地区受到研究者更多的关注,表明洪涝灾害研究的主题与数量受到研究区域的地理位置、气候条件和社会经济发展水平的影响。

基于本体的中文地名识别

针对国内自然语言处理领域地名识别存在的缺点,提出一种基于本体的中文地名识别方法.该方法借助文本工程通用框架GATE,引入构建的地名本体,识别文本中中国县及县以上行政区划地名,使之与地球表面具体的地理位置相对应,进而赋予它们地理坐标和地理语义.重点讨论地名本体的构建、地理解析及地理编码过程中geo/non-geo,geo/geo歧义的消除.实验结果表明该方法能够达到较为理想的准确率和召回率,从而证明geo/non-geo和geo/geo歧义消除算法可行、有效.

Applications of texture attribute analysis to seismic interpretation

The first generation coherence algorithm(namely C1 algorithm) is based on the statistical cross-correlation theory, which calculates the coherency of seismic data along both in-line and cross-line. The work, based on texture technique, makes full use of seismic information in different directions and the difference of multi-traces, and proposes a novel methodology named the texture coherence algorithm for seismic reservoir characterization, for short TEC algorithm. Besides, in-line and cross-line directions, it also calculates seismic coherency in 45° and 135° directions deviating from in-line. First, we clearly propose an optimization method and a criterion which structure graylevel co-occurrence matrix parameters in TEC algorithm. Furthermore, the matrix to measure the difference between multi-traces is constructed by texture technique, resulting in horizontal constraints of texture coherence attribute. Compared with the C1 algorithm, the TEC algorithm based on graylevel matrix is of the feature that is multi-direction information fusion and keeps the simplicity and high speed, even it is of multi-trace horizontal constraint, leading to significantly improved resolution. The practical application of the TEC algorithm shows that the TEC attribute is superior to both the C1 attribute and amplitude attribute in identifying faults and channels, and it is as successful as the third generation coherence.

A Novel Floodless Service Discovery Mechanism Designed for Software-Defined Networking

The low-cost,self-configuration capability and "plug-and-play" feature of Ethernet establishes its dominant position in the local area networks(LAN).However,it is hard to extend to large scale because of the legacy broadcast-based service discovery mechanism.Therefore,to solve this problem,a new split network architecture named Software-Defined Networking(SDN) is introduced in this paper,and a novel floodless service discovery mechanism(FSDM)for SDN is designed.For the FSDM,the widespread broadcast messages for Dynamic Host Configuration Protocol(DHCP) and Address Resolution Protocol(ARP) are considered especially,respectively.Then the DHCP relay and ARP proxy are proposed to handle DHCP broadcast messages and ARP broadcast messages,respectively.The proposed FSDM in this paper can eliminate flooding completely,reserve the autoconfiguration characteristics.Particularly,there is no need to change the existing hardware,software and protocols of hosts for the proposed scheme.Finally,the simulation results are demonstrated to show that our proposed model allows redundant links existed in network and has the property of scalability,which can significantly reduce network traffic in data plane and control traffic in control plane,and decrease the overhead of control plane.

Discussion on the ARP Protocol and Network Security Policy

Network spoofing attacks are very specialized attacks, and network security managers brought a severe test. In this paper, through the analysis of the ARP protocol works, it discusses ARP protocol AR P virus are two common attacks from the IP address to the security risks that exist in the physical address resolution process, and then analyzes in detail, and then introduces the AR P Find virus source and virus removal methods, and finally putting forward effective measures to guard against AR P virus.

中文地名识别与歧义消除——以中国县级以上行政区划地名为例

介绍了本体、地理本体和地名本体的基本概念,探讨了在文本工程通用框架GATE(GeneralArchitecture for Text Engineering)下,以自然语言处理为基础,借助地名本体,完成Web文本的中文地名识别与歧义消除的关键问题,设计并实现了一个原型系统。通过geo/non-geo和geo/geo地名歧义的消除,使得识别出来的地名与地球表面具体的地理位置相对应,进而为Web文本中的中国行政区划地名赋予地理坐标和地理语义。做了验证实验,并对实验结果进行了分析。

Impacts of Non-farm Employment of Rural Laborers on Agricultural Land Use:Theoretical Analysis and Its Policy Implications

During rapid urbanization and industrialization process, non-farm employment of rural laborers has emerged as a prevalent phenomenon in rural areas of China and become an important driving factor for changes in agricultural land use. This article attempts to theoretically analyze the impacts of non-farm employment of rural laborers on agricultural land use based on economic frameworks. As rational agents, farmers aim to maximize their income and follow equilibrium principles when they decide how to allocate their labor forces（or working time） in two departments（farm and non-farm） and how to use their agricultural land with different quality and location. The income earned by non-farm employment is higher, and there exists a comparative advantage between labors, as a result the quantity and quality of labor input in agricultural land use decreases. With the limitation of labor input during agricultural land use decision-making of farm households, on the one hand, land with higher quality is still utilized by farmers. On the other hand, poor quality land will be less well managed and is more likely to be abandoned. Non-farm employment of rural laborers and the rising of opportunity costs will result in abandonment of poor quality land, and great importance should be attached to this by policy makers.