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城市公园免费开放对游客感知价值维度的影响及效应分析——以南京中山陵为例 总被引：4，自引：2，他引：2
基于城市公园免费开放的视角,选取南京中山陵作为研究个案,运用SPSS18.0和AMOS18.0分析软件,通过探索性和验证性因素分析,构建了游客感知价值维度分析模型。研究显示:游客对免费开放中山陵存在五维感知价值,且呈现出感知价格→休闲价值→环境价值→服务价值→文化价值逐步递减的分异特征;由此探究游客感知价值维度分异的作用机制,衍生出城市公园免费开放的效应分析,其中公益福利效应和休闲游憩效应呈现积极的正向发展态势,而生态环境效应、景区服务效应与文化内生效应的发挥则相对滞后。在倡导"以人为本"、关注民生休闲的大众旅游时代,免费开放城市公园在增强城市开放空间优质属性和综合竞争力的同时,其与城市旅游的耦合协调及可持续发展将面临新的挑战。 相似文献
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Konrad Dennerl 《Planetary and Space Science》2008,56(10):1414-1423
X-ray observations of Venus are so challenging that the first detection of Venusian X-rays succeeded only in January 2001, with the Chandra satellite. The X-rays from Venus were found to result from fluorescent scattering of solar X-rays in the Venusian thermosphere. An additional component, caused by charge exchange of highly charged heavy ions in the solar wind with atoms in the Venusian exosphere, was suspected, but could not be unambiguously detected. This was hampered by the fact that the observation occurred during solar maximum, when the solar X-ray flux is highest. In order to investigate the presence of an additional charge exchange component, Venus was observed again in March 2006 and October 2007 with Chandra, taking advantage of the fact that the solar X-ray flux had decreased considerably on its way to solar minimum. In fact, these subsequent observations were able to show that also the Venusian exosphere is emitting X-rays, due to its interaction with the solar wind. Here an overview of all the existing X-ray observations of Venus is presented, including first results from the most recent one, which took place after the arrival of Venus Express, providing the first ever opportunity to combine a remote X-ray observation of a planetary exosphere with simultaneous in situ measurements of the solar wind. 相似文献
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James R. Vermilion Roger N. Clark Thomas F. Greene Jon F. Seamans William F. Yantis 《Icarus》1974,23(1):89-96
Analysis of three occultations of JII (Europa) by JI (Io) has resulted in a preliminary reflectivity map of JII for the hemisphere centered on longitude 324°, a measurement of 1483±20 km for the radius of JII, estimates of the event impact parameters, determination of the mid event times, and a visual geometric albedo, pν = 0.74, for JII. A fourth occultation light curve was used after derivation of the results to confirm their validity. 相似文献
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We have studied by high-resolution X-ray Computed Tomography the effect of crystal clustering on the Shape-Preferred Orientation (SPO) development in synthetic magmas experimentally deformed at 300 MPa and 475–550°C. A fully connected solid network that could potentially induce the onset of yield strength is not achieved in these suspensions containing 16 vol% of crystals. The alumina grain population exhibits a glomeroporphyritic texture made of isolated grains (59.6%) and clusters of touching grains (40.4%). The SPO of the sub-population of isolated grains exhibits foliation and lineation, which are closely parallel to the plane and direction of shear, respectively. The SPO of clustered grains has little influence overall shape fabric. The angular relationships between the average foliation and cluster elongation provide a good indicator of the shear sense. Finally, we highlight the strain partitioning between nearly non-deformed large clusters acting as rigid glomerocrysts and highly sheared zones in low concentrated suspensions. 相似文献
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Asteroid 1984 AB, discovered in January 1984, proved to be a unique object with a close dynamical relationship to Mars. A brief history of the discovery and subsequent “evolution” of the orbit as it was refined is presented. The preliminary orbit of 1984 AB indicated that it might be a Mars Trojan, and an extended discussion of this interesting possibility is presented, but this hypothesis had to be dismissed after further observations had refined the orbit. The semimajor axis and orbital eccentricity are very similar to that of Mars. No other known Mars-crossing asteroid exists with an orbit as closely associated to Mars. 相似文献
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A large number and variety of species of actinomycetes were isolated from sediment samples collected in New York Harbour and from the New York Bight in the course of studies on the distribution of these bacteria in coastal regions. Isolates recovered from the New York Bight sediment were similar to those from other inshore areas, although the total counts were lower. Larger numbers of actinomycetes were recovered from harbour sediments, as well as dredging spoil samples collected from a capped dump site in the New York Bight. The capping operation was monitored and effects on the microbial populations were detected. Selected genera associated with the dredge spoil were determined to be allochthonous, providing useful microbial markers for the dredged material. Many of the microbial species survive in the dump area, but some appear to be metabolically active, perhaps altering the chemical nature of the dumped material. 相似文献
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L. Scharff M. Hort A.J.L. Harris M. Ripepe J.M. Lees R. Seyfried 《Journal of Volcanology and Geothermal Research》2008
We report on the evaluation of in situ measurements of eruption velocities and relative mass flux, collected by Doppler radar, as well as acoustic and infrared data, that were recorded at Stromboli volcano. Doppler radar observations were made alongside thermal, acoustic and seismic measurements, to (1) further investigate the complex waveforms of the SW crater by combining infrasonic, infrared and Doppler radar measurements, (2) establish a relationship between infrared, acoustic and Doppler radar measurements and (3) verify that all instruments observe the same behavior in terms of relative mass eruption rate. We also explore the relationship between kinetic and acoustic energy released during an eruption. Comparing the different methods to each other we are able to show that the mass erupted can be estimated either from the total reflected Doppler radar energy or from infrared observations. However, neither thermal nor reflected energy can provide a value in terms of absolute mass in kg. The erupted masses of different eruptions can only be evaluated relative to each other. Using the combined three data sets we especially focus on the eruption dynamics of the SW crater of Stromboli, namely its fluctuations in eruption strength. These pulses in one eruptive event, so called ’pulsations’ dominate more than 40% of the eruptions of SW crater. Previous models that explain pulsations to be generated by multiple consecutively exploding bubbles are supported by our combined analysis of infrasound, thermal data, particle velocities, and the reflected energy. 相似文献
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我国杰出的寒区水文学家叶柏生研究员不幸因公殉职. 选取了叶柏生研究员若干代表性研究成果, 包括与他人的合作研究成果, 重点从冰川水文、 冻土水文和区域水文变化三方面总结了其对寒区水文学发展所做的创新与贡献. 文章列出了每项研究成果的核心内容, 并给予了简要评述. 所选成果中, 冰川水文方面研究涉及冰川对河川径流的调节作用、 冰川径流对气候变化的响应机理等; 冻土水文研究着重介绍了多年冻土变化对流域径流过程及其变化影响方面的系统性成果; 区域水文变化研究方面, 选取了降水观测误差修正、 气候变化对区域径流的影响等方面的创新成果. 这些研究成果极大地提高了我国在世界寒区水文学研究的地位, 对认识寒区水文过程及气候变化对水资源的影响具有重要科学意义. 相似文献
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