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Use of piezocone tests to predict consolidation yield stress and overconsolidation ratio of lagoonal deposit soil 被引量:4
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作者 童立元 蔡国军 +1 位作者 刘松玉 杜广印 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期112-116,共5页
Existing empirical methods for interpreting the consolidation yield stress and the overconsolidation ratio (OCR) in clays from piezocone tests are briefly reviewed. It can be seen that no universal correlation exist... Existing empirical methods for interpreting the consolidation yield stress and the overconsolidation ratio (OCR) in clays from piezocone tests are briefly reviewed. It can be seen that no universal correlation exists for all worldwide sites. However, for a given clay deposit, there does exist a most appropriate method to reflect the consolidation yield stress and the OCR based on piezocone test data. Three empirical methods are compared based on the piezocone test data collected on Lixia River lagoonal deposit soil sites in the north of Jiangsu province. The objective of this study is to evaluate the validity of the existing relationships linking the consolidation yield stress to piezocone test data and identify the appropriate method for Lixia River lagoonal deposit soil. It is shown that the correlation based on the net tip resistance has much higher accuracy for estimating the consolidation yield stress of lagoonal deposit soil than other methods. 展开更多
关键词 piezocone (CPTU) consolidation yield stress overconsolidation ratio lagoonal deposit correlation
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The analysisof frequent adjustments of legal deposit reserve ratio of People's Bank of Ghina
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作者 邓敏 《大观周刊》 2012年第49期100-100,共1页
关键词 金融机构 金融体制 银行业务 PBOC
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Investigation on the deposition rate and the dilution ratio of plasma surface welding 被引量:6
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作者 王红英 赵昆 +2 位作者 程志国 杨世彦 董祖珏 《China Welding》 EI CAS 2002年第1期55-58,共4页
A new kind of plasma technology with both high deposition rate and low dilution ratio was developed under the calculation and analysis of the arc flame characteristics of plasma arc,the kinematics behavior of powder a... A new kind of plasma technology with both high deposition rate and low dilution ratio was developed under the calculation and analysis of the arc flame characteristics of plasma arc,the kinematics behavior of powder and powder's heating in the arc. Compared with normal plasma surfacing method, the idea using constricting nozzle with small orifice diameter, long plasma arc and increasing the distance from meeting point of the two beams of powder to workpiece, to achieve the goals of high deposition rate and low dilution ratio, was put forward here. In order to prove this idea, a set of experimental system was built up and obtained satisfied results including high deposition rate(more than 25 kg/h )and low dilution ratio(less than 5%). The success of this study offers a promising prospect for developing the powder plasma surface welding in China and may open a way to improve this technology further in efficiency and quality. 展开更多
关键词 PLASMA surface welding deposition rate dilution ratio
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Electrodeposition of Gold to Conformally Fill High-Aspect-Ratio Nanometric Silicon Grating Trenches: A Comparison of Pulsed and Direct Current Protocols 被引量:2
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作者 Sami Znati Nicholas Chedid +3 位作者 Houxun Miao Lei Chen Eric E. Bennett Han Wen 《Journal of Surface Engineered Materials and Advanced Technology》 2015年第4期207-213,共7页
Filling high-aspect-ratio trenches with gold is a frequent requirement in the fabrication of X-ray optics as well as micro-electronic components and other fabrication processes. Conformal electrodeposition of gold in ... Filling high-aspect-ratio trenches with gold is a frequent requirement in the fabrication of X-ray optics as well as micro-electronic components and other fabrication processes. Conformal electrodeposition of gold in sub-micron-width silicon trenches with an aspect ratio greater than 35 over a grating area of several square centimeters is challenging and has not been described in the literature previously. A comparison of pulsed plating and constant current plating led to a gold electroplating protocol that reliably filled trenches for such structures. 展开更多
关键词 PULSED ELECTROPLATING Gold ELECTROPLATING High Aspect ratio TRENCHES Gold Electrodepostion Di-rect Current Electrodeposition PULSED vs. Direct Current ELECTROPLATING Atomic LAYER deposition Platinum Seed LAYER Silicon TRENCH Gratings TRENCH FILLING Grating FILLING ALD Adhesive LAYER
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Rule of Structural Factors in Formation of Porphyry Copper Deposits in South Western Part of Kerman Area, Iran 被引量:17
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作者 Hasan Alizadeh Mehran Arian 《Open Journal of Geology》 2015年第7期489-498,共10页
Kerman area is located in southern parts of central Iranian volcanic belt. The area under study is located in the southern part of this complex copper mineralization in the area, which is mainly porphyry type and is a... Kerman area is located in southern parts of central Iranian volcanic belt. The area under study is located in the southern part of this complex copper mineralization in the area, which is mainly porphyry type and is associated with extensive hydrothermal alteration. This area has a great potential as far as tertiary porphyry copper deposits are concerned. To the exploration of porphyry copper deposits in study area, we have analyzed the lineaments. The lineaments interpreted out from ETM + (band8) data is recognized as another method for locating porphyry type copper mineralization. There is a close correlation between photo lineament factor values and the known copper mineralization in the area. The relationship between 16 porphyry copper deposits with faults and fractures in the area is studied. Photo lineament factor assessments by using satellite photos indicate a strong relationship between a number of lineation intersection in each cell refer to an amount of average lineation in whole map (c/C ratio). In the study area, ratio of c/C even has more relationship refers to PF factor that has previously described in the papers. 展开更多
关键词 PORPHYRY COPPER deposit TECtoNICS COPPER C/C ratio FAULTS Iran
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Enhancement of catalytic and anti-carbon deposition performance of SAPO-34/ZSM-5/quartz films in MTA reaction by Si/Al ratio regulation 被引量:2
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作者 Jiaxin Wu Chenxiao Wang +6 位作者 Xianliang Meng Haichen Liu Ruizhi Chu Guoguang Wu Weisong Li Xiaofeng Jiang Deguang Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期314-324,共11页
In order to further improve the catalytic performance of zeolite catalyst for methanol to aromatics(MTA)technology, the double-tier SAPO-34/ZSM-5/quartz composite zeolite films were successfully synthesized via hydrot... In order to further improve the catalytic performance of zeolite catalyst for methanol to aromatics(MTA)technology, the double-tier SAPO-34/ZSM-5/quartz composite zeolite films were successfully synthesized via hydrothermal crystallization. The Si/Al ratio of SAPO-34 film was used as the only variable to study this material. The composite zeolite material with 0.6Si/Al ratio of SAPO-34 has the largest mesoporous specific surface area and the most suitable acid distribution. The catalytic performance for the MTA process showed that 0.6-SAPO-34/ZSM-5/quartz film has as high as 50.3% benzene-toluenexylene selectivity and 670 min lifetime. The MTA reaction is carried out through the path we designed to effectively avoid the hydrocarbon pool circulation of ZSM-5 zeolite, so as to improve the aromatics selectivity and inhibit the occurrence of deep side reactions to a great extent. The coke deposition behavior was monitored by thermogravimetric analysis and gas chromatograph/mass spectrometer, it is found that with the increase of Si/Al ratio, the active intermediates changed from low-substituted methylbenzene to high-substituted methylbenzene, which led to the rapid deactivation of the catalyst. This work provides a possibility to employ the synergy effect of composite zeolite film synthesizing anti-carbon deposition catalyst in MTA reaction. 展开更多
关键词 Composite zeolite film Methanol to aromatics Anti-carbon deposition Si/Al ratio Hydrocarbon pool circulation mechanism
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Determining pledged loan-to-value ratio:an option pricing perspective 被引量:1
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作者 Ran Zhang Jing Zhang Shuang Xu 《Financial Innovation》 2015年第1期246-258,共13页
Background:We investigated the determination of the pledged loan-to-value ratio in an optionpricing environment and mainly articulated the theoretical framework and analytical method.Methods:The basic idea is that the... Background:We investigated the determination of the pledged loan-to-value ratio in an optionpricing environment and mainly articulated the theoretical framework and analytical method.Methods:The basic idea is that the present value of the pledged loan payoff is equal to a put option’s value.While the interest rate is fixed and the loan is without coupon,we analyzed the pledged loan-to-value ratioin the option pricing perspective and got it that the pledged loan-to-value ratio is decided by term,excessreturn,and the value volatility of the pledge.Next,we extended the same work to coupon loan and portfoliopledge circumstances.For zero coupon and fixed interest rate circumstances,we performed a numericalanalysis.Results:Our results indicate the following:the pledged loan-to-value ratio is a convex decreasing function ofthe term;and the pledged loan-to-value ratio is a concave decreasing function of the value volatility of the pledge;and the pledged loan-to-value ratio is a concave increasing function of the risk premium.For floating interest rate circumstances,we should specify the function form between the loan interest and the risk-free rate.Conclusions:The scientific measurement of the pledged loan-to-value ratio means that simple rules of thumb or the VaR method may lead to mispricing,which could create the possibility of arbitrage.In this way,a new direction for trading derivative products of pledges will be provided. 展开更多
关键词 Pledged loan loan-to-value ratio Put option Term structure of pledged ratio Value volatility of pledge
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Evaluation of Stope Stability in Underground Mine;Hermyingyi (Sn-W Deposit) Mine in Myanmar 被引量:1
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作者 Cho Thae Oo Takashi Sasaoka +3 位作者 Hideki Shimada Akihiro Hamanaka Tun Naing Dyson Moses 《Journal of Geoscience and Environment Protection》 2021年第1期107-120,共14页
The stability of underground excavations has become an important issue in order to extend underground mining operations and extract deeper deposits. The increasing demand for Tin-Tungsten (Sn-W) for industry and its m... The stability of underground excavations has become an important issue in order to extend underground mining operations and extract deeper deposits. The increasing demand for Tin-Tungsten (Sn-W) for industry and its market price has created a motivation for mining companies to extract deep-seated Sn-W ore deposits in Myanmar. Thus, this paper aims to investigate the stability of underground openings, especially, the stope with considering the mining methods. To meet the objective, FLAC<sup>3D</sup> 5.0 simulation was used for the assessment of stope under different stress ratios, 0.5, 1.0, and 1.5 for two types of underground mines;Open stoping and Cut and Fill stoping. The results show that the risk of instability of stope is high under the stress ratio of <em>K</em> = 0.5 than that of <em>K</em> = 1.0 and <em>K</em> = 1.5 in both mining methods. However, the stability of the stope in open stope method is lower than that of cut-and-fill method obviously. This result shows that the appropriate mining method has to be selected for extraction of Sn-W deposit carefully in terms of the balance of safety and cost. 展开更多
关键词 Sn-W deposit Stress ratio Open Stope Cut-and-Fill Stope FLAC3D Simulation
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Effects of V/III ratio on the growth of a-plane GaN films
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作者 谢自力 李弋 +4 位作者 刘斌 张荣 修向前 陈鹏 郑有炓 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期368-372,共5页
The non-polar a-plane GaN is grown on an r-plane sapphire substrate directly without a buffer layer by metal- organic chemical vapour deposition and the effects of V/III ratio growth conditions are investigated. Atomi... The non-polar a-plane GaN is grown on an r-plane sapphire substrate directly without a buffer layer by metal- organic chemical vapour deposition and the effects of V/III ratio growth conditions are investigated. Atomic force microscopy results show that triangular pits are formed at a relatively high V/III ratio, while a relatively low V/III ratio can enhance the lateral growth rate along the c-axis direction. The higher V/III ratio leads to a high density of pits in comparison with the lower V/III ratio. The surface morphology is improved greatly by using a low V/III ratio of 500 and the roughness mean square of the surface is only 3.9 nm. The high resolution X-ray diffraction characterized crystal structural results show that the rocking curve full width at half maximum along the m axis decreases from 0.757° to 0.720°, while along the c axis increases from 0.220° to 0.251° with the V/III increasing from 500 μmol/min to 2000 μmol/min, which indicates that a relatively low V/III ratio is conducible to the c-axis growth of a-plane GaN. 展开更多
关键词 V/III ratio a-plane GaN NON-POLAR metal-organic chemical vapour deposition
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Atomic layer deposition of copper thin film and feasibility of deposition on inner walls of waveguides
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作者 Yuqing XIONG Hengjiao GAO +1 位作者 Ni REN Zhongwei LlU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第3期146-150,共5页
Copper thin films were deposited by plasma-enhanced atomic layer deposition at low temperature,using copper(I)-N,N′-di-sec-butylacetamidinate as a precursor and hydrogen as a reductive gas.The influence of temperatur... Copper thin films were deposited by plasma-enhanced atomic layer deposition at low temperature,using copper(I)-N,N′-di-sec-butylacetamidinate as a precursor and hydrogen as a reductive gas.The influence of temperature,plasma power,mode of plasma,and pulse time,on the deposition rate of copper thin film,the purity of the film and the step coverage were studied.The feasibility of copper film deposition on the inner wall of a carbon fibre reinforced plastic waveguide with high aspect ratio was also studied.The morphology and composition of the thin film were studied by atomic force microscopy and x-ray photoelectron spectroscopy,respectively.The square resistance of the thin film was also tested by a four-probe technique.On the basis of on-line diagnosis,a growth mechanism of copper thin film was put forward,and it was considered that surface functional group played an important role in the process of nucleation and in determining the properties of thin films.A high density of plasma and high free-radical content were helpful for the deposition of copper thin films. 展开更多
关键词 atomic layer deposition COPPER inner wall WAVEGUIDE high aspect ratio
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Suitability of Groundwater from the Kherzet Youcef Lead-Zinc Deposit (North-Eastern Algeria) for Irrigation and Drinking Water Supply
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作者 Souhila Chedda Abdelhamid Haouchine 《Journal of Environmental Protection》 CAS 2022年第12期941-952,共12页
As part of the hydro geological study of the Kherzet Youcef deposit, a drilling battery was carried out. The objective of this achievement is the satisfaction of the water needs of the city of Ain Azel (drinking water... As part of the hydro geological study of the Kherzet Youcef deposit, a drilling battery was carried out. The objective of this achievement is the satisfaction of the water needs of the city of Ain Azel (drinking water supply, irrigation and industrial water supply) and even the transfer to other municipalities suffering by the lack of water and the resumption of mining activity at the deposit of Kherzet Youcef. This water table is located in carbonate formations of Paleo-Neogene age linked to lead-zinc mineralization. Knowledge of water quality and its suitability for human consumption is an obligation. These metals have adverse health effects. We used the results of Sonarem’s analyses from 1973 to 1979. In addition, we carried out two analyses, during two years 2015-2016, on five boreholes. The parameters analyzed are major elements, physical parameters and trace metal elements (Zn, Pb and Fe). The analyses were done by ICP-AES. In our work, it has been shown that waste water is suitable for use in agriculture. For this we used the electrical conductivity at 25°C and those of the sodium adsorption ratio (SAR). For drinking water supply, monitoring the change in trace metal element (Zn, Pb and Fe) for two years has allowed us to conclude that groundwater in the groundwater table east of the Kherzet Youcef fault is generally acceptable. They are eligible by the quality standard set by Algerian regulations. However, they exceed the world health organization (WHO) standards, especially for lead. We recommend a revision of drinking water quality standards set by Algerian regulations, rigorous monitoring of TME content variation and water treatment before distribution. 展开更多
关键词 Trace Metal Element (TME) Quality Standard Sodium Absorption ratio (SAR) Mining Pollution Kherzet Youcef deposit
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Correlation between the Solution Chemistry to Observed Properties of CdTe Thin Films Prepared by CBD Method
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作者 Laxman Gouda Yelameli Ramesh Aniruddha Sheela K. Ramasesha 《Journal of Modern Physics》 2012年第12期1870-1877,共8页
The promising solar material Cadmium Telluride (CdTe) is successfully deposited on both plain glass and ITO coated glass substrates. Many variations in composition of the solution used for deposition of the film are m... The promising solar material Cadmium Telluride (CdTe) is successfully deposited on both plain glass and ITO coated glass substrates. Many variations in composition of the solution used for deposition of the film are made to optimize the deposition conditions. The bandgap calculated from optical transmission studies is found to be a function of the Cd/Te atomic ratio in the film. The atomic ratio in the film is a function of the Cd/Te concentration ratio in the solution used in deposition. Based on several experimental data points an equation involving the Cd/Te atomic ratio in the film and the chemistry of the solution is deduced. 展开更多
关键词 PHOtoVOLTAIC Cell Thin Film CDTE AtoMIC ratio Chemical BATH deposition (CBD)
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Using ^(137)Cs Tracing Methods to Estimate Soil Redistribution Rates and to Construct a Sediment Budget for a Small Agricultural Catchment in the Three Gorges Reservoir Region,China 被引量:7
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作者 JU Li WEN An-bang +2 位作者 LONG Yi YAN Dong-chun GUO Jin 《Journal of Mountain Science》 SCIE CSCD 2013年第3期428-436,共9页
Soil erosion and associated off-site sedimentation are threatening the sustainable use of the Three Gorges Dam. To initiate management intervention to reduce sediment yields, there is an increasing need for reliable i... Soil erosion and associated off-site sedimentation are threatening the sustainable use of the Three Gorges Dam. To initiate management intervention to reduce sediment yields, there is an increasing need for reliable information on soil erosion in the Three Gorges Reservoir Region (TGRR). The purpose of this study is to use 137Cs tracing methods to construct a sediment budget for a small agricultural catchment in the TGRR. Cores were taken from a pond and from paddy fields, for laTCs measurements. The results show that the average sedimentation rate in the pond since 1963 is 1.50 g cm-2 yr-1 and the corresponding amount of sediment deposited is 1,553 t. The surface erosion rate for the sloping cultivated lands and the sedimentation rate in the paddy fields were estimated to be 3,770 t km-2 yr-1 and 2,600 t km-2 yr^1 respectively. Based on the estimated erosion and deposition rates, and the area of each unit, the post 197o sediment budget for the catchment has been constructed. A sediment delivery ratio of 0.5 has been estimated for the past 42 years. The data indicate that the sloping cultivated lands are the primary sediment source areas, and that the paddy fields are deposition zones. The typical land use pattern (with the upper parts characterized by sloping cultivated land and the lower parts by paddy fields) plays an important role in reducing sediment yield from agricultural catchments in the TGRR. A 137Cs profile for the sediment deposited in a pond is shownto provide an effective means of estimating the land surface erosion rate in the upstream catchment. 展开更多
关键词 Pond deposition Soil erosion rate Sediment budget 137Cs Sediment delivery ratio Three Gorges Reservoir Region
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Lithogeochemistry of Intrusive Rocks in the Halo Porphyry Copper-Molybdenum Prospect, Northeast Cambodia 被引量:1
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作者 Seang Sirisokha Kotaro Yonezu +3 位作者 Thomas Tindell Tetsuya Nakanishi Koichiro Watanabe Jocelyn Pelletier 《Open Journal of Geology》 2019年第7期342-363,共22页
The Halo copper-molybdenum prospect is a porphyry system in Ratanakiri province, northeastern part of Cambodia. There is only one research was carried out on this prospect about geological mapping and short wave infra... The Halo copper-molybdenum prospect is a porphyry system in Ratanakiri province, northeastern part of Cambodia. There is only one research was carried out on this prospect about geological mapping and short wave infrared (SWIR) spectroscopy on alteration mineral identification. The purpose of this research is to confirm the deposit type from previous Angkor Gold’s report and find the centre of porphyry deposit based on characteristic of intrusive rocks at surface and subsurface, characteristics of the intrusive rocks and alteration lithogeochemistry of intrusive and volcanic rocks by using Pearce Element Ratio (PER) analysis. PER analysis was used to examine the nature and extend of the alteration halos in the porphyry Halo copper-molybdenum prospect. The intrusive rocks and volcanic rocks in Halo, range from diorite to granite (quartz feldspar porphyry) in composition as well as dacite to trachyandesite (andesite porphyry) in composition, respectively. They were formed in a subduction-related tectonic setting, likely a volcanic arc. Trace elements spider diagrams were normalized to primitive mantle display strong enrichment in large-ion lithophile elements such as Rb, Ba and K and depletion in some high-field strength elements such as Nb and Ti, suggesting magmas generated in a subduction-related tectonic setting. PER analysis indicates a moderate to high degree of sericite alteration of dacites, quartz feldspar porphyries, andesite porphyries and granodiorite porphyries. Moreover, three alterations in the Halo prospect such as potassic (secondary K-feldspar and biotite), phyllic (sericite) and propylitic (epidote) alteration were identified, which are consistent with petrography analysis. The potassic alteration zone is vectoring center of the hydrothermal system which may represent the locus of mineralization. Therefore the geochemical signature of potassic alteration within the quartz feldspar porphyry, andesite porphyry and granodiorite porphyry with high grad of copper ranges up to 2670 ppm and molybdenum ranges up to 5297 ppm represents a character for further exploration in the Halo porphyry copper-molybdenum prospect. 展开更多
关键词 Cambodia Hydrothermal Alteration HALO PORPHYRY Copper-Molybdenite deposit Pearce Element ratio Analysis
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Evaluation of Deposit Insurance Fund Adequacy Using Credit Risk Model--An Indian Experience 被引量:1
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作者 Steward Doss 《Chinese Business Review》 2017年第5期211-233,共23页
There are two methods widely used for evaluating the adequacy of Deposit Insurance Fund: (i) Target Reserve Ratio and (ii) Credit Risk Model. Target Reserve Ratio is one of the macro level indicators more often s... There are two methods widely used for evaluating the adequacy of Deposit Insurance Fund: (i) Target Reserve Ratio and (ii) Credit Risk Model. Target Reserve Ratio is one of the macro level indicators more often set by Regulatory act on the basis of minimum Deposit Insurance Fund margin safety, Target Reserve Ratio is calculated as the ratio of Deposit Insurance Fund to the value of insured deposits. However, TRR does not take into consideration the level of Deposit Insurance potential liability, the Loss at Given Default (LGD) and the historical trend of default rate prevailing among the insured banks. It does not also consider the present condition of the economy and current scenario of the banking sector. This paper discusses primarily about development of Credit Risk Model for evaluating the Deposit Insurance Fund Adequacy. For this purpose, Econometric Credit Risk Model was developed based on the historical data of bank failures and the associated losses of the last 25 years from 1990-91 to 2014-15. The model assesses various possible factors impacting the Deposit Insurance Fund: Default rate, Deposit growth, Exposures, impact of macro-economic factors like GDP, GDS, Inflation and Interest rate changes, etc. on the Deposit Insurance Fund through econometric modeling. The model evaluates the adequacy of Deposit Insurance Fund under both (i) Normal scenarios where there is no (economic) systemic risk assumed and (ii) Worst case scenario at 1% level of significance using Monte Carlo Simulation. Since the model empirically validates all the critical factors impacting the assets and liabilities associated with Loss at Given Default, the model output can also be used to determine a suitable Target Reserve Ratio and such models are being used in countries like USA, Canada, Hong Kong, and Singapore, etc. (IADI, 2009). More importantly, the model outputs are quite useful in determining the adequacy of deposit insurance fund which is an effective risk control measure that organization like Deposit Insurance Credit Guarantee Corporation (DICGC) can adopt both under normal economic scenario as well as worst case scenario, ensuring a strong financial safety net for the banking sector in India. The model also assesses the default probability and the Loss at Given Default of different types of banks: commercial banks, rural banks, cooperative banks, foreign banks, etc. A risk based on premium can possibly be determined for each type of banks in India. 展开更多
关键词 default probability Loss at Given Default Target Reserve ratio assessable deposits cash reserve ratio capital to risk weighted asset ratio
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Optimizing electrophoretic deposition conditions for enhancement in electrical conductivity of carbon fiber/carbon nanotube/epoxy hybrid composites 被引量:1
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作者 王一奇 BYUN Joon-hyung +1 位作者 KIM Byung-sun SONG Jung-il 《Journal of Central South University》 SCIE EI CAS 2012年第11期3017-3022,共6页
The effectiveness of optimizing electrical conductivity of carbon fiber/carbon nanotube (CNT)/epoxy hybrid composites via Taguchi method was demonstrated. CNTs were induced on carbon fabric by electrophoretic deposi... The effectiveness of optimizing electrical conductivity of carbon fiber/carbon nanotube (CNT)/epoxy hybrid composites via Taguchi method was demonstrated. CNTs were induced on carbon fabric by electrophoretic deposition (EPD) technique. The essential deposition parameters were identified as l) the deposition time, 2) the deposition voltage, 3) the mass fraction of CNTs in suspension, and 4) the distance between the electrodes. An experimental design was then performed to establish the appropriate levels for each factor. An orthogonal array of L9 (34) was designed to conduct the experiments. Electrical conductivity results were collected as the response. The relative influences of design parameters on the response were discussed. Using the model, signal to noise (S/N) ratio and response characteristics for the optimized deposition parameter combination were predicted. The results show clearly that the optimum condition of electrophoretic deposition (EPD) process improves the electrical conductivity of carbon/epoxy hybrid composites. 展开更多
关键词 design of experiment electrophoretic deposition carbon nanotube Taguchi method signal to noise (S/N) ratio analysisof variance (ANOVA)
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Theoretical Study on the Confluence of Debris Flow and the Main River
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作者 Guo, Zhixue Huang, Er +2 位作者 Cao, Shuyou Liu, Xingnian Fang, Duo 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期138-142,共5页
Because of the high momentum of debris flow,when it confluences with the Main River,the water level in the upstream of the conjunction point will increase and a portion of sediment will deposit in the con- junction ar... Because of the high momentum of debris flow,when it confluences with the Main River,the water level in the upstream of the conjunction point will increase and a portion of sediment will deposit in the con- junction area.The discharge of downstream will be less then the summation discharge of main river and side channel,and the density of downstream will be difference from both the density of the fluid of main river and tributary.Based on momentum theory,and with the transport coefficient and deposit coef... 展开更多
关键词 debris flow transport coefficient deposit coeffieient water rising discharge ratio density ratio
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Digestive cancer surgery in the era of sentinel node and epithelial-mesenchymal transition
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作者 Nadia Peparini 《World Journal of Gastroenterology》 SCIE CAS 2013年第47期8996-9002,共7页
Lymph node involvement is one of the most important prognostic indicators of carcinoma of the digestive tract.Although the therapeutic impact of lymphadenectomy has not been proven and the number of retrieved nodes ca... Lymph node involvement is one of the most important prognostic indicators of carcinoma of the digestive tract.Although the therapeutic impact of lymphadenectomy has not been proven and the number of retrieved nodes cannot be considered a measure of successful cancer surgery,an adequate lymph node count should be guaranteed to accurately assess the N-stage through the number of involved nodes,lymph node ratio,number of negative nodes,ratio of negative to positive nodes,and log odds,i.e.,the log of the ratio between the number of positive lymph nodes and the number of negative lymph nodes in digestive carcinomas.As lymphadenectomy is not without complications,sentinel node mapping has been used as the rational procedure to select patients with early digestive carcinoma in whom nodal dissection may be omitted or a more limited nodal dissection may be preferred.However,due to anatomical and technical issues,sentinel node mapping and nodal basin dissection are not yet the standard of care in early digestive cancer.Moreover,in light of the biological,prognostic and therapeutic impact of tumor budding and tumor deposits,two epithelial-mesenchymal transition-related phenomena that are involved in tumor progression,the role of staging and surgical procedures in digestive carcinomas could be redefined. 展开更多
关键词 LYMPH NODE count LYMPH NODE ratio SENTINEL NODE TUMOR BUDDING TUMOR deposits
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Grade-Tonnage, Ore Value-Tonnage, andEnrichment Ratio-Tonnage Models forResource Assessment
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作者 Shoji Tetsuya Department of Environment Systems, The University of Tokyo, Tokyo 113-0033, Japan 《Journal of China University of Geosciences》 SCIE CSCD 2001年第1期45-53,共9页
According to grade-tonnage diagrams of nickel and zinc deposits, their critical grades are 0.4 % and 3. 4 %, respectively, and hence the former resources can be considered optimistic and the latter pessimistic. The gr... According to grade-tonnage diagrams of nickel and zinc deposits, their critical grades are 0.4 % and 3. 4 %, respectively, and hence the former resources can be considered optimistic and the latter pessimistic. The grade-tonnage diagram of gold deposits is convex downwards suggesting that the critical grade is 1 X 10-6 in the low-grade part. The ore value (OV)-tonnage diagram of all deposits In the world consists of three parts: high, middle and low vain f classes. The enrichment ratio (ER)-tonnage diagram of all deposits in the world ho consists of three parts: high, middle and low ratio classes.Nine quality categories defined by ER and OV are characterized by some keywords indicating deposit types as follows: category RH (high ER-high OV: 0. 7 %) by 'unconformity' and 'Mississippi Val-ley', category HM (high ER-middle: OV: 0.7 %) by 'vein', category ML (middle ER-low OV: 0 %) by 'sandstone', 'stockwork' and' dissemination', category LM by 'orthomagmatic',' laterite',komatiite and ' chemical', and category LL by 'porphyry', 'dissemination' and 'placer'. Category MM is not characterized by any keyword. If the commodities of a deposit are defined by both the enrichment ratio and the ore value, the defined commodities are relatively coincident for gold and nickel,but different for copper, silver and zinc, and greatly different for molybdenum and lead. Deposits containing lead and/or zinc are complimentary. If the commodity Ph+Zn is applied, most lead or zinc deposits are classified as Ph+Zu by both definitions. Accessory metals are commonly expected for deposits of kuroko-type zinc, epithermal silver, massive sulfide-type zinc and volcanogenic zinc, but uncommon for deposits of orthomagmatic chromium, chemically precipitated copper and sandstone-type uranium. 展开更多
关键词 GRADE ore value enrichment ratio toNNAGE mineral resources deposit model.
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Effects of V/Ⅲ ratio on a-plane GaN epilayers with an InGaN interlayer
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作者 王建霞 汪连山 +7 位作者 杨少延 李辉杰 赵桂娟 张恒 魏鸿源 焦春美 朱勤生 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期14-18,共5页
The effects of V/Ill growth flux ratio on a-plane GaN films grown on r-plane sapphire substrates with an InGaN interlayer are investigated. The surface morphology, crystalline quality, strain states, and density of ba... The effects of V/Ill growth flux ratio on a-plane GaN films grown on r-plane sapphire substrates with an InGaN interlayer are investigated. The surface morphology, crystalline quality, strain states, and density of basal stacking faults were found to depend heavily upon the V/III ratio. With decreasing V/III ratio, the surface morphology and crystal quality first improved and then deteriorated, and the density of the basal-plane stacking faults also first decreased and then increased. The optimal V/III ratio growth condition for the best surface morphology and crystalline quality and the smallest basal-plane stacking fault density of a-GaN films are found. We also found that the formation of basal-plane stacking faults is an effective way to release strain. 展开更多
关键词 V/III ratio a-plane GaN InGaN interlayer metalorganic chemical vapor deposition
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