一组数字化地籍图的接边方法

在数字化地籍测量过程中,必然会有固有的错误引起相邻地块地籍边界定位发生变化。因此就需要平差数字化数据以补偿在数字化地籍测量资料中出现的矛盾和间断。 为了这个目的我们准备用一般在空中三角测量中所用的程序,将每个地图看作是相当于单张像片,并且相邻的一组地图被看作是一个摄影测量区域。建立一个合适的方程式组以对此区域进行     

Is environmental antimony a potential health problem？

Antimony has long been recognized as a non-essential, potentially toxic element. It has recently been suggested, on the basis of measured elemental profiles in peat bogs, that natural levels of Sb in the environment have been overestimated by a factor of 10 and that anthropogenic Sb deposition from the atmosphere has closely followed that of Pb. The implication is that the health effects of environmental Sb may have been seriously underestimated. To examine these propositions, we have compared new data for Sb and Pb in dated cores from four Scottish ombrotrophic peat bogs, Carsegowan Moss, Flanders Moss, Red Moss of Balerno and Turclossie Moss, in southwest, west-central, east-central and northeast Scotland, respectively. Dried peat sections, 1 to 2 cm thick, were subjected to microwave-assisted digestion in nitric/hydrofluoric acid and subsequently analyzed for a range of elements （including Sb, Pb, and the conservative elements Sc, Ti） and Pb isotopic composition by ICP-OES and ICP-MS as appropriate. Three certified reference materials, including NIMT/UOE/FM/001 Peat, were used for quality control purposes. Radiometric dating of upper and lower sections of the cores was carried out using gamma spectrometry for ^21-Pb and accelerator mass spectrometry for ^14C, respectively Some 2000 years ago, in Roman times, both Sb and Pb were clearly elevated in Scottish peat but typically at concentrations below 0.1 mg/kg and 5 mg/kg, respectively, with an average anthropogenic Sb/Pb ratio of-0.01.     

平坦低地农业区人类活动影响下地形对森林分布的影响（英文）

Complex topography buffers forests against deforestation in mountainous regions.However,it is unknown if terrain also shapes forest distribution in lowlands where human impacts are likely to be less constrained by terrain.In such regions,if important at all,topographic effects will depend on cultural-historical factors and thus be human-driven(anthropogenic) rather than natural,except in regions where the general climate or extreme soils limit the occurrence of forests.We used spatial regression modeling to assess the extent to which topographic factors explain forest distribution(presence-absence at a 48×48 m resolution) in a lowland agricultural region(Denmark,43,075 km2) at regional and landscape scales(whole study area and 10×10 km grid cells,respectively),how landscape-scale forest-topography relationships vary geographically,and which potential drivers(topographic heterogeneity,forest cover,clay content,coastal/inland location) determine this geographic heterogeneity.Given a moist temperate climate and non-extreme soils all landscapes in Denmark would naturally be largely forest covered,and any topographic relationships will be totally or primarily human-driven.At regional scale,topographic predictors explained only 5% of the distribution of forest.In contrast,the explanatory power of topography varied from 0%–61% at landscape scale,with clear geographic patterning.Explanatory power of topography at landscape scale was moderately dependent on the potential drivers,with topographic control being strongest in areas with high topographic heterogeneity and little forest cover.However,these conditioning effects were themselves geographically variable.Our findings show that topography by shaping human land-use can affect forest distribution even in flat,lowland regions,but especially via localized,geographically variable effects.     

Orbits of Ten Visual Binary Stars

We present the orbits of ten visual binary stars: WDS 01015 6922, WDS 01424– 0645, WDS 01461 6349, WDS 04374–0951, WDS 04478 5318, WDS 05255–0033, WDS 05491 6248, WDS 06404 4058, WDS 07479–1212, and WDS 18384 0850. We have also determined their masses, dynamical parallaxes and ephemerides.     

冬季高海拔复杂地形下GRAPES-Meso要素预报的检验评估

应用覆盖中国东南部的3 km分辨率GRAPES-Meso4.0模式（GRAPES-Meso4.0_3 km）2015年夏季实时预报试验结果、同区域1600多个中国国家地面气象观测站每日08：00-08：00 BT的24 h累积降水量和逐时降水量观测资料,从降水累积量、降水频率、降水强度、日循环特征等多个角度,对千米尺度分辨率下GRAPES-Meso4.0模式的降水预报性能进行细致评估,并与同版本10 km分辨率业务模式（GRAPES-Meso4.0_10 km）同期结果在相同区域进行类同对比分析和讨论。结果表明：（1）GRAPES-Meso4.0_3 km很好地捕捉到了2015年夏季观测的日均降水量和降水频率的大小及地域分布特征,其一般性降水（中雨及以下）频率平均低于实况约3个百分点,强降水（大雨及以上量级）频率与实况近乎吻合,纠正了GRAPES-Meso4.0_10 km在这两方面存在的显著预报正偏差,均方根误差（RMSE）减小了40%-50%;（2）GRAPES-Meso4.0_3 km在降水强度预报上的优势主要表现为：对降水强度的地域分布细致特征和对短时强降水（雨强≥ 10 mm/h）的频数和分布等把握比较准确,但对强降水（一般性降水）的强度预报偏强（偏弱）;（3）GRAPES-Meso4.0_3 km小时降水量和降水频率的日循环预报可反映出研究区域观测的双峰总体特征以及雨量和频率在日循环中的紧密联系,明显优于GRAPES-Meso4.0_10 km的表现,尽管下午（16时,北京时）峰的预报还存在偏弱现象;（4）模式分辨率提高到千米尺度和模式显式描述云和降水过程,是GRAPES-Meso4.0_3 km降水预报性能较GRAPES-Meso4.0_10 km提高的关键原因,模式初值差异也是不可忽视的影响因素。     

THREE DIMENSIONAL NUMERICAL MODELLING OF FLOW AND SEDIMENT TRANSPORT IN RIVERS

The 3D numerical model, ECOMSED (open source code), was used to simulate flow and sediment transport in rivers. The model has a long history of successful applications to oceanic, coastal and estuarine waters. Improvements in the advection scheme, treatment of river roughness parameterization and shear stress partitioning were necessary to reproduce realistic and comparable results in a river application. To account for the dynamics of the mobile bed boundary, a model for the bed load transport was included in the code. The model reproduced observed secondary currents, bed shear stress distribution and erosion-deposition patterns on a curved channel. The model also successfully predicted the general flow patterns and sediment transport characteristics of a 1-km long reach of the River Klar?lven, located in the north of the county of V?rmland, Sweden.     

Near Real－Time Calculation of Ionospheric Electric Fields and Currents Using GEDAS

This paper presents the recent progress in our project of estimating near real-time electric fields and currents in the ionosphere through our computer system called the Geospace Environment Data Analysis System (GEDAS). We show a new technique in which data from ground magnetometers are collected by the system and used as input for the KRM and AMIE programs to calculate the distribution of ionospheric electric fields and currents, as well as of other ionospheric parameters, such as electric potential patterns. One of the goals of this project is to specify ionospheric processes. Examples of the near real-time calculation and the data flow of our scheme are presented.     

A techno-economic analysis of aquaculture business in Ogun State,Nigeria

Fish supplies 25% of the total protein source in developing countries. A techno-economic analysis was performed for developing a good business proposal for aquaculture loans to enhance aquaculture development in Nigeria. A case study of catfish Clarias gariepinus framing was conducted in Abeokuta North Local Government of Ogun State, Nigeria. The results show that the fixed cost is N18 338 per year, and the variable cost is N459 700 per year, accounting for the largest amount of the total; therefore, a profit of N43 289 per month can be made. Sensitivity analysis was performed to assess any risk(s) that associated with unfavorable changes in government policy with particular reference to monetary policy. Positive net present value shows that the investment in fish farm is economically feasible and the net investment ratio is 3.52. Also, the benefit-cost ratio is 2.17. The internal rate of return (IRR) is 21% showing that the enterprise is able to offset the interest being charged on the loan. It is therefore worthwhile to invest into fish farm business in the study area. The study suggests that to better sustain the local aquaculture business, the government should create a good conducive environment to foster development of the fish farming. Government intervention is urgently needed to solve problems such as in traditional land tenure, grant credit facilities and subsidies, to enhance the aquacultural development in the country.