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旅游环境容量模型的改进及应用探讨 被引量:3
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作者 李金 张跃西 秦艳培 《西南农业大学学报(社会科学版)》 2009年第1期15-18,共4页
通过对旅游环境容量传统量测模型进行评价,认为传统模型未考虑旅游者在景区内时空分布不均衡的问题。传统模型量测所得结果可能导致容量指标的过高估值,容易引起景区超载问题,不利于资源合理利用。在前人研究基础上,根据旅游环境容量自... 通过对旅游环境容量传统量测模型进行评价,认为传统模型未考虑旅游者在景区内时空分布不均衡的问题。传统模型量测所得结果可能导致容量指标的过高估值,容易引起景区超载问题,不利于资源合理利用。在前人研究基础上,根据旅游环境容量自身静态和动态结合的特点,充分考虑到旅游者在时间、空间分布的不平衡,提出了旅游环境容量的改进模型。模型既注重整个景区又不忽视局部景点,计算所得旅游环境容量不管是在宏观,还是微观方面都更趋于合理。模型的应用结合景区先进的经营管理模式,能有效保证热点景点在旅游高峰时刻不超载。从而使整个景区的经济效益和生态效益在一定阶段内达到最大化。最后,以浙江金华双龙景区为例,进行了实证研究。 展开更多
关键词 旅游环境容 量测公式 风景吸引度
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NEW METHOD FOR MEASURING FUZZINESS IN ROUGH SETS 被引量:4
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作者 何亚群 胡寿松 魏崇辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期31-35,共5页
A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy... A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy entropy in rough sets based on equivalence relation are provided, and the properties of the fuzzy entropy are proved. The fuzzy entropy based on equivalent relation is extended to generalize the fuzzy entropy based on general binary relation, and the calculating formula and the equivalent expression of the generalized fuzzy entropy are also given. Finally, an example illustrates the way for getting the fuzzy entropy. Results show that the fuzzy entropy can conveniently measure the fuzziness in rough sets. 展开更多
关键词 rough sets FUZZINESS fuzzy entropy generalized fuzzy entropy
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Karyotype Analysis of the Fiddleneck (Phacelia tanacetifofia Benth.)
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作者 Ugur Ozkan Berk Benlioglu 《Journal of Agricultural Science and Technology(A)》 2015年第5期336-339,共4页
Two varieties of fiddleneck (Phacelia tanacetifolia Benth.) plant were determined for visualizing somatic chromosomes. The 4-5 days old root tips were pre-treated in 6% a-monobromonaphtalane in +4 ℃ for 7.5 h, the... Two varieties of fiddleneck (Phacelia tanacetifolia Benth.) plant were determined for visualizing somatic chromosomes. The 4-5 days old root tips were pre-treated in 6% a-monobromonaphtalane in +4 ℃ for 7.5 h, then fixed in glacial acetic acid for 30 min and transferred to 70% ethanol for long storage. When the root tips were analyzed, they were hydrolyzed with 1 N HCI for 13 min at room temperature (25 ℃). After hydrolyzing, root tips were stained with 2% aceto orcein in darkness for 2.5 h. The squash method for preparation was used for chromosomal investigations. The chromosome length (C), relative length (RL), the long arm (L) and short arm (S) lengths, arm ratio (AR; L/S) and centromefic index (S/C) were calculated for caryologic parameters. The ideograms and detailed chromosome morphology measurements of the species were performed by the use of MicroMeasure 3.3. According to results, fiddleneck (Phacelia tanacetifolia Benth.) has 2n = 22 chromosomes and the karyotype formulas of two varieties of fiddleneck were 16 median and 6 submedian (16 m + 6 sm). 展开更多
关键词 Fiddleneck CYTOGENETIC KARYOTYPE micro measure chromosome number Phacelia tanacetifolia.
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Critical crack tip opening displacement of different strength concrete
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作者 王冰 张秀芳 +1 位作者 戴建国 徐世烺 《Journal of Central South University》 SCIE EI CAS 2011年第5期1693-1699,共7页
Critical crack tip opening displacement (CTODc) of concrete using experimental and analytical evaluation with seven different compressive strengths ranging from 30 up to 150 MPa was studied based on two types of fract... Critical crack tip opening displacement (CTODc) of concrete using experimental and analytical evaluation with seven different compressive strengths ranging from 30 up to 150 MPa was studied based on two types of fracture tests:three-point bending (TPB) and wedge splitting (WS).In the tests,the values of CTODc were experimentally recorded using a novel technique,in which fiber Bragg grating (FBG) sensors were used,and two traditional techniques,in which strain gauges and clip gauges were deployed.The values of CTODc of tested concrete were also predicted using two existing analytical formulae proposed by JENQ & SHAH and XU,respectively.It is found that the values of CTODc obtained by both experimental measurements and analytical formulae exhibit a negligible variation as the compressive strength of concrete increases,and the test geometry adopted has little impact on the value of CTODc.Regarding the experimental measurement of CTODc,the clip gauge method generally leads to a larger value of CTODc and shows a more significant scatter as compared with the other two methods,while the strain gauge method leads to a slightly lower CTODc as compared with the FBG sensor method.The analytical formula proposed by JENQ and SHAH is found to generally lead to an overestimation,while the analytical formula proposed by XU shows a good accuracy. 展开更多
关键词 critical crack tip opening displacement (CTODo) fiber Bragg grating (FBG) sensors three-point bending (TPB) tests wedge splitting (WS) tests high strength CONCRETE
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Aerodynamic Performance of Wind Microturbines and Their Dynamic Response
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作者 Gordon Breeze 《Journal of Civil Engineering and Architecture》 2016年第3期261-267,共7页
Wind microturbines typically have rotor diameters of 2 m or less. This paper presents theoretical expressions that can be used to determine the aerodynamic performance of wind microturbines. A commercially-available t... Wind microturbines typically have rotor diameters of 2 m or less. This paper presents theoretical expressions that can be used to determine the aerodynamic performance of wind microturbines. A commercially-available three-bladed microturbine was tested at the outlet plane of a wind tunnel. The cross-section dimensions of the wind tunnel jet are 2.5 m (horizontal) x 1.5 m (vertical). The tested microturbine has a diameter of 1.2 m, and it generates a maximum power output of about 300 W. The paper provides the wind tunnel test methodology that was used to determine the mean and fluctuating forces generated by the aforementioned wind microturbine. Both the static and dynamic responses of the turbine were measured, and results from this testing are presented in this paper. These results enable the trends and predictions of the theoretical expressions to be compared with wind tunnel measurements. It is shown that, for this particular microturbine, the behaviours of these test measurements are consistent with the expected theoretical predictions. 展开更多
关键词 MICROTURBINE WIND TUNNEL aerodynamic performance FORCES DYNAMICS
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Measuring Carbon Dioxide Sink of Betung Bamboo (Dendrocallamus asper (Schult f.) Backer ex Heyne) by Sinusoidal Curves Fitting on Its Daily Photosynthesis Light Response 被引量:1
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作者 Effendi Tri Bahtiar Naresworo Nugroho Anne Carolina Aditya Chandra Maulana 《Journal of Agricultural Science and Technology(B)》 2012年第7期780-788,共9页
Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditiona... Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages. 展开更多
关键词 Carbon sink Betung bamboo daily photosynthesis light response sinusoidal curve fitting.
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Predicting Pepper Fruit Yield Based on Temperature and Solar Radiation
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作者 Eviatar Ityel Lior Avraham +1 位作者 Hana Alon Rivka Offenbach 《Journal of Agricultural Science and Technology(B)》 2014年第5期360-367,共8页
Two separate experiments were conducted in bell pepper (Capsicum annum L.) in order to evaluate the effects of temperature and radiation on fruit yield. The results of the temperature experiment were integrated into... Two separate experiments were conducted in bell pepper (Capsicum annum L.) in order to evaluate the effects of temperature and radiation on fruit yield. The results of the temperature experiment were integrated into the radiation experiment to give an overall empirical model for potential pepper fruit yield grown in greenhouse. In the temperature experiment, pepper plants were planted during the summer time of Israel in the Arava region in a commercial, one hectare greenhouse, equipped with a cooling wet-mat system. Eleven plots were assigned along the 80 m down the row from the wet mat. Air seasonal temperatures were affected by the distance from the wet-mat and linearly increased at the rate of 0.036 ℃/m, while relative humidity was not affected. Fruit yield dropped from 19.4 kg/m at a distance of 20 m, to 13.1 kg/m2 at 80 m away from the wet-mat, respectively. Yield regression decreased linearly with increased temperature at -11%/℃. In the radiation experiment, during the summer time of Israel in the Western Negev region, three sweet pepper varieties were grown under six radiation treatments, which accumulated to the following relative global radiation fractions (lint/lout): 0.72, 0.61, 0.46, 0.38, 0.32 and 0.21 from outside radiation. The three varieties did not differ in their response to radiation. The seasonal temperature normalized yield response to radiation quantity at 21 ℃ (Y21) yielded a linear regression formula with a slope of 7.6 × 10^-3 kg/m^2/MJ. The multiplicative model of temperature and radiation on fruit yield was found to predict well the potential fruit yield for various locations and seasons in Israel. 展开更多
关键词 Sweet pepper GREENHOUSE RADIATION TEMPERATURE MODEL fruit yield.
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Relationship between in situ sound velocity and granular characteristics of seafloor sediments in the Qingdao offshore region
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作者 张严心 郭常升 +2 位作者 王景强 侯正瑜 陈文景 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期704-711,共8页
The sound velocity of seafloor sediments from shallow seas can provide important information for harbor design, and ocean and seacoast engineering projects. In this study, in situ measurements were used to obtain accu... The sound velocity of seafloor sediments from shallow seas can provide important information for harbor design, and ocean and seacoast engineering projects. In this study, in situ measurements were used to obtain accurate sediment sound velocities at 45 stations offshore of Qingdao. The relationships between the sound velocity and granular properties of the seafloor sediments were analyzed. Sound velocity showed an increase with the sand content, sand-clay ratio, and sorting coefficient; and a nonlinear decreasing trend with increasing mean grain size and clay content. We plotted a sound velocity distribution map, which shows that the sound velocity was closely related to the geological environment. Previous empirical equations suggested by Hamilton, Anderson, and Liu were used to calculate the velocity with grain size. A comparison between the measured and calculated velocities indicates that the empirical equations have territorial limitations, and extensive data are essential to establish global empirical equations. Future work includes the calibration of the laboratory acoustic measurements with an in situ technique. 展开更多
关键词 sound velocity granular properties empirical equation
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