The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging fr...The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging from room temperature to 800 °C.Our results show that:1) the temperature has not clear effect on the mechanical properties of limestone from room temperature to 600 °C.However, the mechanical properties of limestone deteriorate rapidly when the temperature is above 600 °C.In this case, the peak stress and modulus of elasticity decrease rapidly.When the temperature reaches 800 °C, the entire process, showing the stress-strain curve is displayed indicating an obvious state of plastic-deformation;2) the failure mode of limestone shows the breakdown of tensile strength from room temperature to 600 °C, as well as the compress shearing damage over 600 °C;3) combining our test results with the concept of thermal damage, a thermal damage equation was derived.展开更多
To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failur...To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failure modes are presented by analyzing damage behaviors, and their characteristics are pointed out respectively. Furthermore, the damage process is analyzed and the causes of structural damage in different levels are studied. Finally, by comparing deformation and vibration status of domes with different failure modes, the principles of different failures are revealed and an integrated frame of damage mechanism is set up.展开更多
This study analyses the possibilities for optimal land use structure in mountainous areas of rural Serbia, which is faced with problems such as unfavorable terrain characteristics and inadequate land use patterns caus...This study analyses the possibilities for optimal land use structure in mountainous areas of rural Serbia, which is faced with problems such as unfavorable terrain characteristics and inadequate land use patterns causing economic underdevelopment and increasing population migration. In the case of a small privately owned farm in Western Serbia, optimal land use pattern is determined using the linear programming model. The objective function-cost-effectiveness or soil erosion reduction, as well as constraints, are formulated using the benefit-cost ratio(BCR) for a 15-year production period and soil losses data calculated using the Universal Soil Loss Equation(USLE). The best results are achieved using the scenario with the aim to minimize soil erosion, considering the BCR in the constraints. This scenario is proposed since it was registered that the benefit for landowners would increase by five times, while the losses of land would decline about 80%. The sensitivity analysis of investments is performed to check whether the price variation affects the cost-effectiveness of proposed land use. Results show that market changes(nine cases are considered) do not lead to significant changes in land use allocation. Proposed land use pattern improves the environmental condition, strengthens the rural economy and thus offers the greatest potential for sustainable development of mountainous rural areas.展开更多
In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five ...In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five age groups was used in this study. Immunohistochemical labeling, quantitative analysis of mRGC morphology, open field test （OFT）, and statistical analysis were used. In comparison with C57 BL/6 mice, the age-matched CFP-D2 mice had significantly elevated intraocular pressure （lOP）. We observed parallel morphological changes in the retina, including a reduction in the density of cyan fluorescent protein- （CFP） expressing cells （cells mm^-2 at 2 months of age, 1309±26; 14 months, 878±30, P〈0.001）, mRGCs （2 months, 48_＋3; 14 months, 19±4, P〈0.001）, Brn3b-expressing RGCs （2 months, 1283±80; 14 months, 950±31, P〈0.001）, Brn-3b expressing mRGCs （5 months, 50.17%±5.5%; 14 months, 12.61%±3.8%, P〈0.001）, and reduction in the dendritic field size of mRGCs （mm^2 at 2 months, 0.077±0.015; 14 months, 0.065±0.015, P〈0.05）. CFP-D2 mice had hyperactive locomotor activity patterns based on OFT findings of the total distance traveled, number of entries into the center, and time spent in the center of the testing apparatus. The glaucoma induced hyperactive response pattern could be associated with dysfunctional mRGCs, most likely Brn-3b-positive mRGCs in CFP-D2 mice.展开更多
This paper introduces a new economic model of a wartime economy, the war economic capability model--WEC-Model. The WEC-Model assesses the eco- nornic impact of an armed conflict in three different stages： （1） initi...This paper introduces a new economic model of a wartime economy, the war economic capability model--WEC-Model. The WEC-Model assesses the eco- nornic impact of an armed conflict in three different stages： （1） initial armed conflict and diplomatic negotiations; （2） military armed conflict; and （3） winners and losers in the post-armed conflict stage. The analysis makes use of new indicators such as economic desgrowth （-δ）, armed conflict intensity （αi）, armed conflict losses （-π）, economic wear （Л）, level of armed conflict tension （ζ）, level of diplomatic nego- tiations （η）, and total economic leaking （Ωt. To illustrate the model, we apply it to evaluate an imaginary armed conflict between the People＇s Republic of China and Japan.展开更多
基金Projects 50490273 supported by the National Natural Science Foundation of China2007CB209400 by the National Basic Research Program of China+1 种基金08KJD130003 by the Basic Research Program of University in Jiangsu ProvinceXKY2007219 by Xuzhou Institute of Technology
文摘The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging from room temperature to 800 °C.Our results show that:1) the temperature has not clear effect on the mechanical properties of limestone from room temperature to 600 °C.However, the mechanical properties of limestone deteriorate rapidly when the temperature is above 600 °C.In this case, the peak stress and modulus of elasticity decrease rapidly.When the temperature reaches 800 °C, the entire process, showing the stress-strain curve is displayed indicating an obvious state of plastic-deformation;2) the failure mode of limestone shows the breakdown of tensile strength from room temperature to 600 °C, as well as the compress shearing damage over 600 °C;3) combining our test results with the concept of thermal damage, a thermal damage equation was derived.
基金Sponsored by the National Natural Science Foundation of China(Grant No.90715034)
文摘To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failure modes are presented by analyzing damage behaviors, and their characteristics are pointed out respectively. Furthermore, the damage process is analyzed and the causes of structural damage in different levels are studied. Finally, by comparing deformation and vibration status of domes with different failure modes, the principles of different failures are revealed and an integrated frame of damage mechanism is set up.
基金a part of the Project No.43007,subproject No.16 funded by the Ministry of Education,Science and Technological Development of the Republic of Serbia
文摘This study analyses the possibilities for optimal land use structure in mountainous areas of rural Serbia, which is faced with problems such as unfavorable terrain characteristics and inadequate land use patterns causing economic underdevelopment and increasing population migration. In the case of a small privately owned farm in Western Serbia, optimal land use pattern is determined using the linear programming model. The objective function-cost-effectiveness or soil erosion reduction, as well as constraints, are formulated using the benefit-cost ratio(BCR) for a 15-year production period and soil losses data calculated using the Universal Soil Loss Equation(USLE). The best results are achieved using the scenario with the aim to minimize soil erosion, considering the BCR in the constraints. This scenario is proposed since it was registered that the benefit for landowners would increase by five times, while the losses of land would decline about 80%. The sensitivity analysis of investments is performed to check whether the price variation affects the cost-effectiveness of proposed land use. Results show that market changes(nine cases are considered) do not lead to significant changes in land use allocation. Proposed land use pattern improves the environmental condition, strengthens the rural economy and thus offers the greatest potential for sustainable development of mountainous rural areas.
基金supported by the National Basic Research Program of China (2009CB320900 to Pu MingLiang,2011CB510206 to Pu MingLiangand Gao Jie)National Natural Science Foundation of China(30831160516 to Pu MingLiang)+2 种基金NIH EY04067 (N.C. Brecha)VAMerit Review (N.C. Brecha).supported by a summer fellowship from the PKU-UCLA Joint Research Institute
文摘In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five age groups was used in this study. Immunohistochemical labeling, quantitative analysis of mRGC morphology, open field test （OFT）, and statistical analysis were used. In comparison with C57 BL/6 mice, the age-matched CFP-D2 mice had significantly elevated intraocular pressure （lOP）. We observed parallel morphological changes in the retina, including a reduction in the density of cyan fluorescent protein- （CFP） expressing cells （cells mm^-2 at 2 months of age, 1309±26; 14 months, 878±30, P〈0.001）, mRGCs （2 months, 48_＋3; 14 months, 19±4, P〈0.001）, Brn3b-expressing RGCs （2 months, 1283±80; 14 months, 950±31, P〈0.001）, Brn-3b expressing mRGCs （5 months, 50.17%±5.5%; 14 months, 12.61%±3.8%, P〈0.001）, and reduction in the dendritic field size of mRGCs （mm^2 at 2 months, 0.077±0.015; 14 months, 0.065±0.015, P〈0.05）. CFP-D2 mice had hyperactive locomotor activity patterns based on OFT findings of the total distance traveled, number of entries into the center, and time spent in the center of the testing apparatus. The glaucoma induced hyperactive response pattern could be associated with dysfunctional mRGCs, most likely Brn-3b-positive mRGCs in CFP-D2 mice.
文摘This paper introduces a new economic model of a wartime economy, the war economic capability model--WEC-Model. The WEC-Model assesses the eco- nornic impact of an armed conflict in three different stages： （1） initial armed conflict and diplomatic negotiations; （2） military armed conflict; and （3） winners and losers in the post-armed conflict stage. The analysis makes use of new indicators such as economic desgrowth （-δ）, armed conflict intensity （αi）, armed conflict losses （-π）, economic wear （Л）, level of armed conflict tension （ζ）, level of diplomatic nego- tiations （η）, and total economic leaking （Ωt. To illustrate the model, we apply it to evaluate an imaginary armed conflict between the People＇s Republic of China and Japan.
