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81.
    
The Penn State/ NCAR Mesoscale Model (MM5) is used to simulate the precipitation event that occurred during 1–2 May 1994 to the south of the Yangtze River. In five experiments the Kain–Fritsch scheme is made use of for the subgrid–scale convective precipitation, but five different resolvable–scale microphysical parameterization schemes are employed. They are the simple super-saturation removal scheme, the warm rain scheme of Hsie et al. (1984), the simple ice scheme of Dudhia (1989), the complex mixed–phase scheme developed by Reisner et al. (1993), and the GSFC microphysical scheme with graupel. Our interest is how the various resolvable-scale schemes affect the domain-averaged precipitation, the precipitation distribution, the sea level pressure, the cloud water and the cloud ice. Through a series of experiments about a warm sector rainfall case, results show that although the different resolvable-scale scheme is used, the differences of the precipitation characteristics among all five runs are not very obvious. However, the precipitation is over-predicted and the strong mesoscale low is produced by the simple super-saturation removal scheme. The warm rain scheme with the inclusion of condensation and evaporation under-predicts the precipitation and allows the cloud water to reach the 300 hPa level. The scheme of the addition of graupel increases the resolvable-scale precipitation by about 20%-30%. The inclusion of supercooled liquid water in the grid-scale scheme does not affect significantly the results.  相似文献   
82.
建立省级数字高程模型(DEM)的关键技术——以江苏省为例   总被引:8,自引:2,他引:6  
王库  于东升  史学正 《地理科学》2004,24(2):188-192
文章以江苏省的DEM制作为例,介绍利用ARCINFO、ARCVIEW软件生成DEM的全过程中的关键技术。应用结果表明,可以快速查找出采编地形图信息过程中的错误,建立的DEM精度较高,更适合于水土流失的定量监测,显示了该技术方法的可行性。  相似文献   
83.
During the French-American Mid-Oceanic Undersea Survey (FAMOUS) the French team participating in the mission explored the active A transform fault with the diving saucer CYANA, and discovered a characteristic hydrothermal deposit. The results presented here concern the structural and radiochemical study of three samples: two metalenriched samples and one sample of consolidated calcareous sediment recovered from the area.It is shown that there is a chemical segregation between silica and iron on one hand, and manganese in the other hand, and that on such deposits the layer-by-layer radio-chemical analysis of the uranium series is not applicable.Three different age estimations may be made:In the managanese encrustation, thorium 230 is depleted towards equilibrium with its parent uranium 234, suggesting a maximum age of 45,000 years to the deposit.On the contrary, the outermost layer, 0.1 cm thick, formed essentially with loose sediment stained with oxides, presents an excess of thorium 230. The Σ230Th(excess)/cm2 may be used to calculate a minimum age of 20 years.Such a sediment thickness, in this area, corresponds to a time span of 50 years.  相似文献   
84.
针对传统测绘工程专业难以适应当前新经济环境,需要进行改造升级的现状,本文以闽江学院测绘工程专业为研究对象,依托现有测绘工程、地理信息科学和导航工程等3个专业,通过合理联动、适时修改测绘工程专业的教学大纲与教学内容,将地理信息科学和导航工程专业的相关教学资源融入测绘工程专业,建立以地理学、计算机科学与技术、测绘科学与技术为主线的现代测绘工程课程体系。以现有的"测绘地理信息专业群"为基础,构建了以地方特色产业发展和需要为导向、学科交叉互补的新型学科发展体系,提出了测绘工程专业多学科交叉复合改造的具体途径与方式。最后,建立了基于测绘工程专业改造升级的无人机遥感监测与应急测绘应用新方向并形成新的课程体系,以期为新经济环境下测绘工程专业人才的培养、学科发展、教学管理等提供参考。  相似文献   
85.
ABSTRACT

We employed integrated methods to assess the landslide movement in Sv. Anton town in the Western Carpathians Neogene Volcanic Field (Central Slovakia). The integrated diagnostics required study of the landslide kinematic activity by a combination of Global Navigation Satellite Systems (GNSS) and Electrical Resistivity Tomography (ERT) imaging from November 2013 to March 2015. A topographic model with 2-cm accuracy was constructed from Unmanned Aerial Vehicles (UAV) photogrammetry. Continuous spatial datasets of movement and displacement field vectors were interpolated from the measured movements over the entire study period. Although deformation studies in Slovakia have a long-term tradition, complex interdisciplinary studies in urbanized areas are still lacking. This inspired our main objectives: to identify landslide kinematics and to reconstruct and define the rates of annual landslide movement obtained from geodetic measurement at the monitoring points. Our results demonstrate how landslide integrated diagnostics contribute to the detection of slope instability, with a maximum velocity of 60.82 mm/yr during the summer period. The precipitation effects are consistent with the Sv. Anton landslide displacement acceleration, and the following increases in total monthly precipitations are staggering compared to long-term monthly averages: July precipitation increased by 175.3%, August by 203.3%, and September by 198.1%.  相似文献   
86.
Gallerias are the underground constructed results of mining. As these space in underground layers collapse, horizontal and vertical ground movements occur and movement which may reach the earth’s surface are known as mining subsidence. The result of underground displacement may cause surface ground movement which can be detrimental to masonry buildings especially in hard coal regions. Thorough familiarity with general and regional characteristics of an affected area can assist reduction of the effects. Zonguldak and the nearby settlement area, with a population of 300,000, constitute the centre of a hard coal basin where extensive mining has a history extending through 160 years. Mining constitutes the main economic activity in this region, and consequently influences every aspect of life. This study’s intent is to identify the effects of mining subsidence on masonry buildings in the mining area of Kozlu, Zonguldak, Turkey and illustrate them with selected images of damaged masonry buildings. Also included are satellite and mining galleria images.  相似文献   
87.
V381 Cas is a relatively bright and early-type eclipsing binary system. Several new times of its eclipses were measured as part of our long-term observational project of eccentric eclipsing binaries. Based on a current OC diagram solution, we found for the first time that its orbit is slightly eccentric (e = 0.025) and shows a very rapid apsidal advance with short period of about 20 years only. The relativistic and third body effects are negligible, being about 3% of the total apsidal motion rate.  相似文献   
88.
Variations in the global atmospheric electric circuit are investigated using a wide range of globally spaced instruments observing VLF (∼10 kHz) waves, ELF (∼300 Hz) waves, Schumann resonances (4–60 Hz), and the atmospheric fair weather electric field. For the ELF/VLF observations, propagation effects are accounted for in a novel approach using established monthly averages of lightning location provided by the Lightning Image Sensor (LIS) and applying known frequency specific attenuation parameters for daytime/nighttime ELF/VLF propagation. Schumann resonances are analyzed using decomposition into propagating and standing waves in the Earth-ionosphere waveguide. Derived lightning activity is compared to existing global lightning detection networks and fair weather field observations. The results suggest that characteristics of lightning discharges vary by region and may have diverse effects upon the ionospheric potential.  相似文献   
89.
A policy network analysis using a questionnaire survey was conducted to identify the main climate policy actors in South Korea and examine how they form alliances and come into conflict over four major issues. Generally, it was found that governmental organizations are the main actors in the South Korean climate policy arena and that they mediate between the business and civil sectors. In particular, key organizations in each sector play a leading role in the formation and maintenance of at least two distinct alliance networks: growth and environmental. In particular, the growth network has been stronger and more intense than the environmental network, with the exception of nuclear power policy. The crucial drivers of proactive policy discourse in South Korea have been scientific discourse and a consensus on the advent of anthropogenic climate change by the international scientific community, the international climate change negotiations and the pressure to commit to GHG emissions reduction, and low-carbon green growth strategy.

Policy relevance

The positions of South Korean governmental organizations (as well as other civil society organizations) on the four major issues of climate policy have not been aligned. The government has not acted as a unified body; instead it is an aggregated body composed of organizations with competing interests. If policy actors with different interests share the recognition of the state of the country within global society and understand international pressure as well as the urgency of combating climate change, then a common policy goal can be achieved. It is essential for the government to exert proactive leadership for climate policies in mediating the growth and environmental networks. It is important to boost environmental networks in order to overcome the alliance of growth networks. A more proactive response for combating climate change would establish open policy-making processes for environmental network actors and provide economic opportunities for climate actions.  相似文献   
90.
The effect of starvation on physiological and biochemical indicators of body, muscle and hepatopancreas were investigated for juvenile red swamp crawfish (Procambarus clarkii), and the results showed the effect was obvious. In a 70-day starvation experiment, mean body weight, exuvial rate, ab- dominal muscle ratio and hepatosomatic index decreased significantly. The percentage of protein, fat, ash and moisture were also significantly affected. The protein content decreased sharply at Day 30 onward and the percentage of fat decreased rapidly from Day 50 and on. The percentages of ash and moisture started to increase significantly at Day 40 and 30 respectively. After the starvation experiment, the hepa- topancreatic total and neutral lipid content decreased slightly from 23.90% to 20.39% and 73.75% to 70.35%, while the hepatopancreatic polar lipid content increased from 23.81% to 27.32%. On the other hand, all the muscular total, neutral and polar lipid contents, and the muscular fatty acid compositions did not change significantly except for the hepatopancreatic fatty acid composition. The relative percentages of 14:0, 16:0, 16:1n-7 and 18:1n-9 were decreased by 55.17%, 11.11%, 8.5% and 6.70% from the initial values, and the relative percentages of 18:2n-6, 18:3n-3, 20:4n-6, 20:5n-3 and 22:6n-3 increased obvi- ously from 5.2%, 3.9%, 2.4%, 10.6%, and 13.7% to 7.1%, 5.0%, 2.8%, 11.5%, and 14.4% respectively. Preference of utilization of fatty acids from hepatopancreas during starvation was as follows: 14:0>16:0>16:1n-7>18:1n-9, and the conservation of highly unsaturated fatty acids was in the order of: 18:2n-6 >18:3n-3>20:4n-6>20:5n-3>22:6n-3.  相似文献   
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