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The Impact of the Digital Economy on Financial Regulatory Costs: An Empirical Analysis Based on the Solow Growth Model
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作者 Dong Kang 《Contemporary Social Sciences》 2024年第5期70-94,共25页
As a novel economic form,the digital economy is reshaping the financial regulatory landscape and significantly impacting regulatory costs.This paper incorporates the digital economy and financial regulatory costs into... As a novel economic form,the digital economy is reshaping the financial regulatory landscape and significantly impacting regulatory costs.This paper incorporates the digital economy and financial regulatory costs into the classic Solow growth model,uncovering an inverted U-shaped relationship between them.A subsequent mechanism analysis explains the rationale behind this relationship.To empirically examine this relationship in China,the paper utilizes inter-provincial panel data from 2013 to 2021 and employs methodologies such as the two-way fixed effects and moderating effects models.These analyses have important implications for the sound and sustainable development of China’s financial industry.The findings indicate:(a)As China’s digital economy develops,its impact on financial regulatory costs follows an inverted U-shaped pattern,initially increasing and then declining.This conclusion remains valid after robustness tests.(b)The influence of the digital economy on regulatory costs depends on favorable external conditions.Specifically,the impact is more pronounced in regions and periods with better digital infrastructure and more abundant human capital.(c)Additionally,redundant resources moderate this impact,which can weaken the inverted U-shaped relationship.Our findings not only provide a theoretical foundation for understanding the impact of the digital economy on financial regulatory costs but also offer valuable policy insights for optimizing financial regulation in China. 展开更多
关键词 digital economy financial regulatory costs Solow growth model
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Toward a sustainable growth path in Arab economies:an extension of classical growth model
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作者 Amjad Taha Mucahit Aydin +2 位作者 Taiwo Temitope Lasisi Festus Victor Bekun Narayan Sethi 《Financial Innovation》 2023年第1期621-644,共24页
Background/Objectives:Many economies are on the trajectory of alternative growth drivers other than conventional capital and labor.Access to credit facilities is a pertinent indicator of economic growth.In line with t... Background/Objectives:Many economies are on the trajectory of alternative growth drivers other than conventional capital and labor.Access to credit facilities is a pertinent indicator of economic growth.In line with the United Nations Sustainable Development Goals(UNSDGs-8)agenda,the national goal for sustainable development for most economies and Arab economies is no exception.Therefore,the current study adopts a traditional growth model by exploring the relationship between gross domestic product(GDP)per capita,credit for private sectors,ratio of exports,real GDP,and per labor force participants for selected Arab economies annually from 2001 to 2020.Research design:This study leverages the Fourier Kwiatkowski–Phillips–Schmidt–Shin(KPSS)unit root test and second-generation panel econometrics as estimation techniques,such as Westerlund and Edgerton panel cointegration test,and the use of two estimators,namely the augmented mean group(AMG)and common correlated error mean group(CCEMG),to obtain robust results.Findings:Empirical findings from Westerlund and Edgerton panel cointegration tests validate the long-run equilibrium relationship among the outlined variables.Further empirical results indicate that the share of exports is negatively significant with economic growth in countries such as Kuwait,Lebanon,Tunisia,and Jordan.Additionally,savings and labor force participation have a positive relationship with economic growth in individual countries such as Algeria and Bahrain.As per the panel,there is no significant relationship between labor force participation and economic growth.This indicates that the skilled labor force enhanced economic growth.Conclusions:These findings come with inherent far-reaching policy suggestions for economies and panels.Further details on country-specific policy actions are presented in the concluding section. 展开更多
关键词 Arab economies Classical growth model Panel econometrics SDG Savings-investment
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Evolution of Growth Model and Cultivation of Competitive Advantages Under the Ambidextrous Innovation Strategy: In the Case of China’s High-Tech Enterprises
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作者 Xinyuan Zhang Chee Heong Quah Mohammad Nazri Bin Mohd Nor 《Proceedings of Business and Economic Studies》 2023年第1期26-30,共5页
This study focuses on the evolution of growth model and cultivation of competitive advantages under the ambidextrous innovation strategy.After a brief introduction of the connotation of ambidextrous innovation strateg... This study focuses on the evolution of growth model and cultivation of competitive advantages under the ambidextrous innovation strategy.After a brief introduction of the connotation of ambidextrous innovation strategy,the evolution of growth model of high-tech enterprises under the conventional strategy and the ambidextrous innovation strategy is analyzed.Furthermore,a discussion is made on how to cultivate enterprises’competitive advantages under the ambidextrous innovation strategy,thereby enabling enterprises to stand out from competitors under this new strategic model and truly achieve the goal of sustainable development. 展开更多
关键词 Ambidextrous innovation strategy Competitive advantages growth model Technological flexibility
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SAR Data Assimilation for Crop Biomass Simulation Based on Crop Growth Model 被引量:3
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作者 谭正 刘湘南 +1 位作者 张晓倩 吴伶 《Agricultural Science & Technology》 CAS 2012年第5期1127-1132,共6页
Biomass from SAR data was assimilated into crop growth model to describe relationship between crop biomass and crop growth time to improve estimation accuracy of biomass. In addition, inverse model was established in ... Biomass from SAR data was assimilated into crop growth model to describe relationship between crop biomass and crop growth time to improve estimation accuracy of biomass. In addition, inverse model was established in order to estimate biomass according to relationship between biomass and backscattering coefficients from SAR data. Based on cost function, parameters of growth model were optimized as per conjugate gradient method, minimizing the differences between estimated biomass and inversion values from SAR data. The results indicated that the simulated biomass using the revised growth model with SAR data was consistent with the measured one in time distribution and even higher in accuracy than that without SAR data. Hence, the key parameters of crop growth model could be revised by real-time growth information from SAR data and accuracy of the simulated biomass could be improved accordingly. 展开更多
关键词 Data assimilation BIOMASS SAR Crop growth model
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Growth model of cavity generated by the projectile impacting liquid-filled tank 被引量:3
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作者 Bei-lei Zhao Ji-guang Zhao +2 位作者 Cun-yan Cui Yong-sheng Duan Yan Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期609-616,共8页
The high-speed impact of a projectile on a liquid-filled tank causes the hydraulic ram,in which a cavity is formed.To study the growth characteristics of the cavity,the formation mechanism of the cavity is analyzed.Th... The high-speed impact of a projectile on a liquid-filled tank causes the hydraulic ram,in which a cavity is formed.To study the growth characteristics of the cavity,the formation mechanism of the cavity is analyzed.The effect of Reynolds number and Mach number on drag coefficient is considered,the axial and radial growth models of the cavity are established respectively.The relative errors between the cavity length calculated by the axial growth model,the cavity diameter calculated by the radial growth model and Ma L.Y.test results are less than 20%,which verifies the effectiveness of the axial and radial growth models.Finally,numerical simulation is carried out to study the growth characteristics of the cavity caused by the projectile impacting the satellite tank at the velocity of 4000 m/s.The cavity length and diameter calculated by the axial and radial growth models agree well with those obtained by simulation results,indicating that the cavity length and diameter in satellite tank can be accurately calculated by the axial and radial growth models. 展开更多
关键词 PROJECTILE Impact Liquid-filled tank CAVITY Axial growth model Radial growth model
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Comparison of six statistical approaches in the selection of appropriate fish growth models 被引量:6
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作者 朱立新 李丽芳 梁振林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期457-467,共11页
The performance of six statistical approaches,which can be used for selection of the best model to describe the growth of individual fish,was analyzed using simulated and real length-at-age data.The six approaches inc... The performance of six statistical approaches,which can be used for selection of the best model to describe the growth of individual fish,was analyzed using simulated and real length-at-age data.The six approaches include coefficient of determination(R2),adjusted coefficient of determination(adj.-R2),root mean squared error(RMSE),Akaike's information criterion(AIC),bias correction of AIC(AICc) and Bayesian information criterion(BIC).The simulation data were generated by five growth models with different numbers of parameters.Four sets of real data were taken from the literature.The parameters in each of the five growth models were estimated using the maximum likelihood method under the assumption of the additive error structure for the data.The best supported model by the data was identified using each of the six approaches.The results show that R2 and RMSE have the same properties and perform worst.The sample size has an effect on the performance of adj.-R2,AIC,AICc and BIC.Adj.-R2 does better in small samples than in large samples.AIC is not suitable to use in small samples and tends to select more complex model when the sample size becomes large.AICc and BIC have best performance in small and large sample cases,respectively.Use of AICc or BIC is recommended for selection of fish growth model according to the size of the length-at-age data. 展开更多
关键词 growth model model selection statistical approach Akalke's information criterion Bayesian information criterion
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Individual-tree diameter growth model for Korean pine plantations based on optimized interpolation of meteorological variables 被引量:6
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作者 Man Wang Yinghui Zhao +1 位作者 Zhen Zhen Xingji Jin 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1535-1552,共18页
To explore the influence of meteorological variables on the growth of Korean pine(Pinus koraiensis Sieb.et Zucc.) plantations and provide a scientific reference for the production and management of Korean pine,three a... To explore the influence of meteorological variables on the growth of Korean pine(Pinus koraiensis Sieb.et Zucc.) plantations and provide a scientific reference for the production and management of Korean pine,three approaches to interpolate meteorological variables during the growing season(i.e.,May-September) were compared in Heilongjiang Province,China.Optimized meteorological variable interpolation results were then combined with stand and individual tree variables,based on data from 56 sample plots and 2886 sample trees from Korean pine plantations in two regions of the province to develop an individualtree diameter growth model(Model I) and an individualtree diameter growth model with meteorological variables(Model Ⅱ) using a stepwise regression method.Moreover,an individual-tree diameter growth model with regional effects(Model Ⅲ) was developed using dummy variables in the regression,and the significance of introducing these dummy variables was verified with an F-test statistical analysis.The models were validated using an independent data set,and the predictive performance of the three models was assessed via the adjusted coefficient of determination(R_(a)^(2)) and root mean square error(RMSE).The results suggest that the growth increment in tree diameter of Korean pine plantations was significantly correlated with the natural logarithm of initial diameter(ln D),stand basal area(BAS),logarithmic deformation of the stand density index(ln SDI),ratio of basal area of trees larger than the subject tree to their initial diameter at breast height(DBH)(BAL/D),and the maximum growingseason precipitation(Pgmax).The individual-tree diameter growth models of Korean pine plantations developed in this study will provide a good basis for estimating and predicting growth increments of Korean pine forests over larger areas. 展开更多
关键词 Mixed interpolation Korean pine plantations Individual-tree diameter growth model Regional effects
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Discrete Software Reliability Growth Modeling for Errors of Different Severity Incorporating Change-point Concept 被引量:4
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作者 D.N.Goswami Sunil K.Khatri Reecha Kapur 《International Journal of Automation and computing》 EI 2007年第4期396-405,共10页
Several software reliability growth models (SRGM) have been developed to monitor the reliability growth during the testing phase of software development. In most of the existing research available in the literatures... Several software reliability growth models (SRGM) have been developed to monitor the reliability growth during the testing phase of software development. In most of the existing research available in the literatures, it is considered that a similar testing effort is required on each debugging effort. However, in practice, different types of faults may require different amounts of testing efforts for their detection and removal. Consequently, faults are classified into three categories on the basis of severity: simple, hard and complex. This categorization may be extended to r type of faults on the basis of severity. Although some existing research in the literatures has incorporated this concept that fault removal rate (FRR) is different for different types of faults, they assume that the FRR remains constant during the overall testing period. On the contrary, it has been observed that as testing progresses, FRR changes due to changing testing strategy, skill, environment and personnel resources. In this paper, a general discrete SRGM is proposed for errors of different severity in software systems using the change-point concept. Then, the models are formulated for two particular environments. The models were validated on two real-life data sets. The results show better fit and wider applicability of the proposed models as to different types of failure datasets. 展开更多
关键词 Discrete software reliability growth model non-homogeneous Poisson process fault severity change point probability generating function.
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Effects of Lvy noise and immune delay on the extinction behavior in a tumor growth model 被引量:3
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作者 郝孟丽 徐伟 +1 位作者 谷旭东 戚鲁媛 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期126-132,共7页
The combined effects of Ltvy noise and immune delay on the extinction behavior in a tumor growth model are explored, The extinction probability of tumor with certain density is measured by exit probability. The expres... The combined effects of Ltvy noise and immune delay on the extinction behavior in a tumor growth model are explored, The extinction probability of tumor with certain density is measured by exit probability. The expression of the exit probability is obtained using the Taylor expansion and the infinitesimal generator theory. Based on numerical calculations, it is found that the immune delay facilitates tumor extinction when the stability index α〈 1, but inhibits tumor extinction when the stability index α 〉 1. Moreover, larger stability index and smaller noise intensity are in favor of the extinction for tumor with low density. While for tumor with high density, the stability index and the noise intensity should be reduced to promote tumor extinction. 展开更多
关键词 exit probability Levy noise immune delay tumor growth model
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A Knowledge Model-and Growth Model-Based Decision Support System for Wheat Management 被引量:3
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作者 ZHU Yan, CAO Wei-xing, WANG Qi-meng, TIAN Yong-chao and PAN Jie(Key Laboratory of Crop Growth Regulation , Ministry of Agriculture/Nanjing Agricultural University, Nanjing 210095 , P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2003年第11期1212-1220,共9页
By applying the system analysis principle and mathematical modeling technique to knowledge expression system for crop cultural management, the fundamental relationships and quantitative algorithms of wheat growth and ... By applying the system analysis principle and mathematical modeling technique to knowledge expression system for crop cultural management, the fundamental relationships and quantitative algorithms of wheat growth and management indices to variety types, ecological environments and production levels were analysed and extracted, and a dynamic knowledge model with temporal and spatial characters for wheat management(WheatKnow)was developed. By adopting the soft component characteristics as non language relevance , re-utilization and portable system maintenance. and by further integrating the wheat growth simulation model(WheatGrow)and intelligent system for wheat management, a comprehensive and digital knowledge model, growth model and component-based decision support system for wheat management(MBDSSWM)was established on the platforms of Visual C++ and Visual Basic. The MBDSSWM realized the effective integration and coupling of the prediction and decision-making functions for digital crop management. 展开更多
关键词 Wheat management Knowledge model growth model Soft component Decision support system
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Crystal Growth Models of Dexamethasone Sodium Phosphate in a MSMPR Reactive Crystallizer 被引量:2
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作者 郝红勋 王静康 +1 位作者 王永莉 侯宝红 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期350-354,共5页
The reactive crystallization process of dexamethasone sodium phosphate was investigated in a continuous mixed-suspension, mixed-product-removal(MSMPR) crystallizer. Analyzing experimental data, it was found that the g... The reactive crystallization process of dexamethasone sodium phosphate was investigated in a continuous mixed-suspension, mixed-product-removal(MSMPR) crystallizer. Analyzing experimental data, it was found that the growth of product crystal was size-dependent. The Bransom, CR, ASL, M J2 and M J3 size-dependent growth models were discussed in details. Using experimental steady state population density data of dexamethasone sodium phosphate, parameters of five size-dependent growth models were determined by the method of non-linear least-squares. By comparison of experimental population density and linear growth rate data with those obtained from the five size-dependent growth models, it was found that the MJ3 model predicts the growth more accurately than do the other four models. Based on the theory of population balance, the crystal nucleation and growth rate equations of dexamethasone sodium phosphate were determined by non-linear regression method. The effects of different operation parameters such as supersaturation, magma density and temperature on the quality of product crystal were also discussed, and the optimal operation conditions were derived. 展开更多
关键词 dexamethasone sodium phosphate growth model crystal size distribution(CSD) population balance equation
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Transitions in a Logistic Growth Model Induced by Noise Coupling and Noise Color 被引量:2
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作者 SHI Jin ZHU Shi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期175-182,共8页
With unified colored noise approximation, the logistic growth model is used to analyze cancer cell population when colored noise is included. It is found that both the coupling between noise terms and the noise color... With unified colored noise approximation, the logistic growth model is used to analyze cancer cell population when colored noise is included. It is found that both the coupling between noise terms and the noise color can induce continuous first-order-like and re-entrance-like phase transitions in the system. The coupling and the noise color can also increase tumor cell growth for small number of cell mass and repress tumor cell growth for large number of cell mass. It is shown that the approximate analytic expressions are consistent with the numerical simulations. 展开更多
关键词 logistic growth model first-order-like phase transition re-entrance-like phase transition colored noise
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Unsuspected implications arising from assumptions in simulations: insights from recasting a forest growth model in system dynamics 被引量:2
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《Forestry Studies in China》 CAS 2014年第1期-,共10页
Background:Familiarity with a simulation platform can seduce modellers into accepting untested assumptions for convenience of implementation.These assumptions may have consequences greater than commonly suspected,and ... Background:Familiarity with a simulation platform can seduce modellers into accepting untested assumptions for convenience of implementation.These assumptions may have consequences greater than commonly suspected,and it is important that modellers remain mindful of assumptions and remain diligent with sensitivity testing.Methods:Familiarity with a technique can lead to complacency,and alternative approaches and software can reveal untested assumptions.Visual modelling environments based on system dynamics may help to make critical assumptions more evident by offering an accessible visual overview and empowering a focus on representational rather than computational efficiency.This capacity is illustrated using a cohort-based forest growth model developed for mixed species forest.Results:The alternative model implementation revealed that untested assumptions in the original model could have substantial influence on simulated outcomes.Conclusions:An important implication is that modellers should remain conscious of all assumptions,consider alternative implementations that reveal assumptions more clearly,and conduct sensitivity tests to inform decisions. 展开更多
关键词 Forest growth model Validity of assumptions Visual modelling environment FORTRAN SIMILE System dynamics Swindle
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A Rice Growth Models (RGM) System by Object-Oriented Programming with Visual C++ 被引量:1
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作者 MI Xiang-cheng, ZOU Ying-bin, SHI Ji-cheng, CAI Sheng and PENG Zheng-wen(College of Plant Science and Technology, Hunan Agricultural University, Changsha 410128 , P. R. China Ningxiang Agricultural Bureau of Hunan Province , Ningxiang 410600 , P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2002年第10期1133-1140,共8页
Object-oriented programming divides the crop production into subsystems and simulates their behaviors. Many classes were designed to simulate the behaviors of different parts or different physiological processes in cr... Object-oriented programming divides the crop production into subsystems and simulates their behaviors. Many classes were designed to simulate the behaviors of different parts or different physiological processes in crop production system. At the same time, many classes have to be employed for bettering user's interface. But how to manage these classes on a higher level to cooperate them into a perfect system is another problem to study. The Rice Growth Models (RGM) system represents an effort to define and implement a framework to manage these classes. In RGM system, the classes were organized into the model-document-view architecture to separate the domain models, data management and user interface. A single document with multiple views interface frame window was adopted in RGM. In the architectures, the simulation models only exchange data with documents while documents act as intermediacies between simulation models and interfaces. Views get data from documents and show the results to users. The classes for the different functions can be grouped into different architectures. Different architectures communicate with each other through documents. The classes for the different functions can be grouped into different architectures. By using the architecture, communication between classes is more efficient. Modeler can add classes in architectures or other architectures to extend the system without having to change system structure, which is useful for construction and maintenance of agricultural system models. 展开更多
关键词 RICE growth model Object-oriented plogramming
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Construction of a growth model in the green alga Tetraselmis subcordiformis using a response surface approach
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作者 王辉 牛景彦 +2 位作者 刘佳慧 杨洪帅 刘志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期537-545,共9页
The green alga Tetraselmis subcordiformis has been widely used as a quality live food for aquaculture species, and also has been studied as a model organism for the photo-biological production of hydrogen. We attempte... The green alga Tetraselmis subcordiformis has been widely used as a quality live food for aquaculture species, and also has been studied as a model organism for the photo-biological production of hydrogen. We attempted to quantify the relationship between T. subcordiformis specific growth rate (SGR) and three important environmental factors (temperature, salinity, and pH) using the central composite design and response surface method under laboratory conditions. The results showed that the linear effects of temperature and salinity were significant (P〈0.05), and they were equally important in impacting T. subcordiformis specific growth; the linear effect of pH was not significant (P〉0.05); the interactive effect of temperature and pH was significant (P〈0.05), whereas the temperature ~ salinity and salinity x pH interactions were not significant (P〉0.05); all of the quadratic effects of the three factors were significant (P〈0.05). A model equation for specific growth rate with the three factors was established, with the unadjusted and predictive R2 as high as 0.990 and 0.921, respectively, suggesting that the model was a very good fit and that it could be used to predict SGR. Through optimizing the reliable model, an optimal 3-factor combination of 25~C/35 of salinity/pH 7.9 was obtained, at which the maximum specific growth rate (0.65) was recorded, with a desirability value of 93.8%. These experimental results could serve as guidelines for increasing T. subcordiformis production efficiency. 展开更多
关键词 Tetraselmis subcordiformis specific growth TEMPERATURE SALINITY PH growth model
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An imputation/copula-based stochastic individual tree growth model for mixed species Acadian forests: a case study using the Nova Scotia permanent sample plot network
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作者 John A. Kershaw Jr Aaron R. Weiskittel +1 位作者 Michael B. Lavigne Elizabeth McGarrigle 《Forest Ecosystems》 SCIE CSCD 2017年第4期251-263,共13页
Background: A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection... Background: A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection system. Methods: The Nova Scotia, Canada permanent sample plot network is used as a case study to develop and test the modelling approach. Predictions from this model are compared to predictions from the Acadian variant of the Forest Vegetation Simulator, a widely used statistical individual tree growth and yield model. Results: Diameter and height growth rates were predicted with error rates consistent with those produced using statistical models. Mortality and ingrowth error rates were higher than those observed for diameter and height, but also were within the bounds produced by traditional approaches for predicting these rates. Ingrowth species composition was very poorly predicted. The model was capable of reproducing a wide range of stand dynamic trajectories and in some cases reproduced trajectories that the statistical model was incapable of reproducing. Conclusions: The model has potential to be used as a benchmarking tool for evaluating statistical and process models and may provide a mechanism to separate signal from noise and improve our ability to analyze and learn from large regional datasets that often have underlying flaws in sample design. 展开更多
关键词 Nearest neighbor imputation Copula sampling Individual tree growth model Mortality INgrowth Mixed species stand development Acadian forests Nova Scotia
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A growth model for a hyalid amphipod Hyale perieri in the coastal water of Alexandria(Egypt)
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作者 Zakaria H.Y Dowidar N.M. +1 位作者 El-Komi M.M. Atta M.M. 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期221-232,共12页
The growth rate of the hyalid amphipod Hyale perieri was studied on the bases of Ikeda'sgrowth model which is based on the inter moult period (IP) and moult increament (△BL). To apply this approach, laboratory ex... The growth rate of the hyalid amphipod Hyale perieri was studied on the bases of Ikeda'sgrowth model which is based on the inter moult period (IP) and moult increament (△BL). To apply this approach, laboratory experiments were carried out at three temperatures regimes (15℃, 20℃, 25℃ ) to gain accurate data of IP and BL. The total number of specimens used in this study was 86 at 15℃ , 24 at 20℃ and 70 at 25℃. The number of flagellar segments of both antennae of the Hyale perieri could not be used as an index of growth (instar criterion). The obtained results indicated that, the predicted IP of the specimens was inversely related to temperature and in good agreement with the observed values at the experimental temperatures. IP data obtained from laboratory-reared specimes are combined with ABL data to establish a growth model for Hyale perieri from its release from the mar-supium (1.64 mm BL ) to the maximum size (12.67 mm BL) as a function of temperature. The maximum numbers of consecutive moults recorded during the experiment were 13 moults (14 instar) at 15℃, 14 moults (15 instar) at 20℃ and 12 moults (13 instar) at 25℃ . The predicted life span for BL = 12.67 mm (moult 13) was 203.82 d at 15t, for BL = 11.75 mm (moult 14) was 138.94 d at 20℃ and for BL = 8.65 mm (moult 12) was 75.40 d at 25℃ respectively, thus confirming that the life span of the species is inversely proportional to temperature. Within the experimental temperatures tested, the optimum temperature for the growth of the species was 20℃. 展开更多
关键词 growth model inter moult period and moult increament hyalid amphipod Hyale perieri coastal water of Alexandria
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Reliability Growth Modeling and Optimal Release Policy Under Fuzzy Environment of an N-version Programming System Incorporating the Effect of Fault Removal Efficiency
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作者 P.K.Kapur Anshu Gupta P.C.Jha 《International Journal of Automation and computing》 EI 2007年第4期369-379,共11页
Failure of a safety critical system can lead to big losses. Very high software reliability is required for automating the working of systems such as aircraft controller and nuclear reactor controller software systems.... Failure of a safety critical system can lead to big losses. Very high software reliability is required for automating the working of systems such as aircraft controller and nuclear reactor controller software systems. Fault-tolerant softwares are used to increase the overall reliability of software systems. Fault tolerance is achieved using the fault-tolerant schemes such as fault recovery (recovery block scheme), fault masking (N-version programming (NVP)) or a combination of both (Hybrid scheme). These softwares incorporate the ability of system survival even on a failure. Many researchers in the field of software engineering have done excellent work to study the reliability of fault-tolerant systems. Most of them consider the stable system reliability. Few attempts have been made in reliability modeling to study the reliability growth for an NVP system. Recently, a model was proposed to analyze the reliability growth of an NVP system incorporating the effect of fault removal efficiency. In this model, a proportion of the number of failures is assumed to be a measure of fault generation while an appropriate measure of fault generation should be the proportion of faults removed. In this paper, we first propose a testing efficiency model incorporating the effect of imperfect fault debugging and error generation. Using this model, a software reliability growth model (SRGM) is developed to model the reliability growth of an NVP system. The proposed model is useful for practical applications and can provide the measures of debugging effectiveness and additional workload or skilled professional required. It is very important for a developer to determine the optimal release time of the software to improve its performance in terms of competition and cost. In this paper, we also formulate the optimal software release time problem for a 3VP system under fuzzy environment and discuss a the fuzzy optimization technique for solving the problem with a numerical illustration. 展开更多
关键词 Fault tolerant software reliability growth model release time fuzzy optimization.
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Construction of Clonal Growth Models in Trifolium repens
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作者 HUBaozhong LI Fenglan HU Xiaomei HU Guofu YUAN Qiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第4期14-18,共5页
The suitability of models for describing the clonal growth of Trifolium repens population was discussed. The results showed that deterministic models were inadequate for describing its clonal growth, but the diffusion... The suitability of models for describing the clonal growth of Trifolium repens population was discussed. The results showed that deterministic models were inadequate for describing its clonal growth, but the diffusion models and the randomwalk models suited for the clonal growth characteristics of the population. And it was found that random-walk models were better than diffusion models for describing a population in an environment with rich natural resources, and the latter was better in a poor environment. 展开更多
关键词 Trifolium repens clonal growth model diffusion model random-walk model
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Studies on crop growth modelling and simulation models in China
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作者 Wang Shili and Wang FutangChinese Academy of Meteorological Science, SMA , Beijing 100081, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1992年第1期60-65,共6页
There is a close relationship between agricultural production and environmental meteorological conditions. In the study of the correlation between them, the simulation models are paid more attention to the crop growth... There is a close relationship between agricultural production and environmental meteorological conditions. In the study of the correlation between them, the simulation models are paid more attention to the crop growth. In this paper the development of the studies on the crop growth dynamic simulation model in China is briefly reviewed. The relationships between meteorological conditions and each process of crop growth (such as photosynthesis, respiration, accumulation and distribution of assimilation products and growth of leaf area) are studied and simulated basing on the results from field experiments. Preliminary models for rice, wheat, maize and soybean have been developed, and some investigations about modelling methods, procedures and parameters in simulation models are made. 展开更多
关键词 simulation model crop growth modelling.
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