A new measurement technique is used to determine the settlement of bridge pile foundation and the thickness of deep compressed soft layer. The finite element Plaxis 3D foundation program is used in the analysis with a...A new measurement technique is used to determine the settlement of bridge pile foundation and the thickness of deep compressed soft layer. The finite element Plaxis 3D foundation program is used in the analysis with a proposed empirical equation to modify the input parameters represented by the soil compression modulus. The results of the numerical analysis using the proposed empirical equation provide insight to the settlement analysis of pile groups in soft clayey soils; consequently, the finite element Plaxis 3D program can be a useful tool for numerical analysis. The numerical analysis is modified by adjusting the calculation of compression modulus from those obtained under pressure between 100-200 kPa by which the results of the settlement are modified and thus matching the realistic measurements. The absolute error is 3 mm which is accepted compared with the last researches. This scenario can be applied for the similar problems in the theoretical applications of deep foundations.展开更多
Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided int...Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided into 5 metallogenic factors （element assemblages）. The high values of F1 , F2 and F4 together indicate overlapped of multiple stages of gold mineralization, revealing high potential of gold mineralization at depth ; the single high value of F4 represents the root of an existing ore body while high values of F3 and F4 show the intervals of barton sectors in the lode. Comprehensive geochemical studies show the high prospeetion potential below the 14^th level and between lines 39-71. It is also prospective to look for blind ore-bodies between lines 15-29 and below the 10^th level.展开更多
In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on...In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on these companies. Investment cycle is also affected by information asymmetry. The less asymmetric the information is, the more information investors get and the longer the investment cycle is. The adjustment frequency is also restricted by financial strength. This paper measures the debt maturity structure of the firm as the weighted average of debt maturity, and it is more precise than the ratio of long term debt to total debt. In empirical tests on debt maturity, the results show that financial strength, volatility of return and asymmetric information all have negative impacts on debt maturity.展开更多
An effective flotation approach is proposed for improving the recovery of molybdenite fines from a finely-disseminated molybdenum ore. To maximize the flotation recovery of molybdenum, process mineralogy of raw ore, c...An effective flotation approach is proposed for improving the recovery of molybdenite fines from a finely-disseminated molybdenum ore. To maximize the flotation recovery of molybdenum, process mineralogy of raw ore, contrast tests, optimization of operation conditions and particle size analysis were systematically investigated. Process mineralogy suggests that in the raw ore, 61.63% of molybdenite particles distribute in the 〈20 pm size fraction, and intergrow with muscovite and pyrite as the contained and disseminated type. Contrast tests indicate that conventional flotation responds to poor collection efficiency for particles less than 25 pm. Oil agglomerate flotation （OAF） process demonstrates an obvious superiority in improving the flotation recovery of molybdenite fines. Furthermore, the flotation results of OAF process reveal that the dosage of transformer oil plays a critical role on the average size of collected mineral particles （d（0）, agglomerates （d^0） and the molybdenum recovery. In addition, industrial tests illustrate that compared with the Mo-S bulk flotation approach, OAF process not only increases Mo recovery and grade of molybdenum concentrate by 22.75% and 17.47% respectively, but also achieves a sulfur concentrate with a superior grade of 38.92%.展开更多
In this paper we demonstrate that price-to-income ratio （PIR） is the most precise indicator of measuring bubble levels in China＇s urban hoasing market under current conditions. We have built a model to measure the ...In this paper we demonstrate that price-to-income ratio （PIR） is the most precise indicator of measuring bubble levels in China＇s urban hoasing market under current conditions. We have built a model to measure the reasonable PIR ceiling. Based on current mortgage rates, loan terms and down payment ratios, we conclude that the reasonable PIR for China ＇s urban residents should lie between 4.38-6.78 and should not exceed 7. 7hen, using statistical data, we calculate current PIR in China ＇s major cities. With reference to proper PIR, we conclude the existence of bubbles in China ＇s urban housing market; in particular, bubbles hace grown enormously large in some first-tier cities, which pose a huge financial risk. Based on the above analysis, we propose some policy suggestions to carefully deflate the bubbles in these housing markets.展开更多
基金Project(SWJT11ZT04)supported by the Central College Foundation of ChinaProject(2008g032-A)supported by the Major Projects S&T Foundation of China’s Ministry of Railways,China
文摘A new measurement technique is used to determine the settlement of bridge pile foundation and the thickness of deep compressed soft layer. The finite element Plaxis 3D foundation program is used in the analysis with a proposed empirical equation to modify the input parameters represented by the soil compression modulus. The results of the numerical analysis using the proposed empirical equation provide insight to the settlement analysis of pile groups in soft clayey soils; consequently, the finite element Plaxis 3D program can be a useful tool for numerical analysis. The numerical analysis is modified by adjusting the calculation of compression modulus from those obtained under pressure between 100-200 kPa by which the results of the settlement are modified and thus matching the realistic measurements. The absolute error is 3 mm which is accepted compared with the last researches. This scenario can be applied for the similar problems in the theoretical applications of deep foundations.
文摘Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided into 5 metallogenic factors （element assemblages）. The high values of F1 , F2 and F4 together indicate overlapped of multiple stages of gold mineralization, revealing high potential of gold mineralization at depth ; the single high value of F4 represents the root of an existing ore body while high values of F3 and F4 show the intervals of barton sectors in the lode. Comprehensive geochemical studies show the high prospeetion potential below the 14^th level and between lines 39-71. It is also prospective to look for blind ore-bodies between lines 15-29 and below the 10^th level.
文摘In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on these companies. Investment cycle is also affected by information asymmetry. The less asymmetric the information is, the more information investors get and the longer the investment cycle is. The adjustment frequency is also restricted by financial strength. This paper measures the debt maturity structure of the firm as the weighted average of debt maturity, and it is more precise than the ratio of long term debt to total debt. In empirical tests on debt maturity, the results show that financial strength, volatility of return and asymmetric information all have negative impacts on debt maturity.
基金Project（2016zztsl03） supported by the Fundamental Research Funds for the Central Universities, China Project（51374249） supported by the National Natural Science Foundation of China+1 种基金 Project（2015BAB12B02） supported by the National Key Technology R＆D Program of China Project（2013B090800016） supported by Guangdong Provincial Science and Technology Plan, China
文摘An effective flotation approach is proposed for improving the recovery of molybdenite fines from a finely-disseminated molybdenum ore. To maximize the flotation recovery of molybdenum, process mineralogy of raw ore, contrast tests, optimization of operation conditions and particle size analysis were systematically investigated. Process mineralogy suggests that in the raw ore, 61.63% of molybdenite particles distribute in the 〈20 pm size fraction, and intergrow with muscovite and pyrite as the contained and disseminated type. Contrast tests indicate that conventional flotation responds to poor collection efficiency for particles less than 25 pm. Oil agglomerate flotation （OAF） process demonstrates an obvious superiority in improving the flotation recovery of molybdenite fines. Furthermore, the flotation results of OAF process reveal that the dosage of transformer oil plays a critical role on the average size of collected mineral particles （d（0）, agglomerates （d^0） and the molybdenum recovery. In addition, industrial tests illustrate that compared with the Mo-S bulk flotation approach, OAF process not only increases Mo recovery and grade of molybdenum concentrate by 22.75% and 17.47% respectively, but also achieves a sulfur concentrate with a superior grade of 38.92%.
文摘In this paper we demonstrate that price-to-income ratio （PIR） is the most precise indicator of measuring bubble levels in China＇s urban hoasing market under current conditions. We have built a model to measure the reasonable PIR ceiling. Based on current mortgage rates, loan terms and down payment ratios, we conclude that the reasonable PIR for China ＇s urban residents should lie between 4.38-6.78 and should not exceed 7. 7hen, using statistical data, we calculate current PIR in China ＇s major cities. With reference to proper PIR, we conclude the existence of bubbles in China ＇s urban housing market; in particular, bubbles hace grown enormously large in some first-tier cities, which pose a huge financial risk. Based on the above analysis, we propose some policy suggestions to carefully deflate the bubbles in these housing markets.
