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Biological function of resveratrol and its application in animal production:a review 被引量:4
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作者 Qingwei Meng Jiawei Li +1 位作者 Chunsheng Wang Anshan Shan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期864-886,共23页
With the prohibition of antibiotics in feed,plant functional substances have been widely studied as feed additives.Resveratrol,a natural stilbene,and a non-flavonoid polyphenol found in plants,possesses antioxidant,an... With the prohibition of antibiotics in feed,plant functional substances have been widely studied as feed additives.Resveratrol,a natural stilbene,and a non-flavonoid polyphenol found in plants,possesses antioxidant,anti-inflammatory,and metabolic regulatory features.Resveratrol generated intense scientific and public interest,primarily due to its widely reported ability to prevent cancer,delay aging and alleviate related metabolic diseases.Recently,resveratrol has been studied and applied as a feed additive in animal production.This review focuses on the outline of the absorption and metabolism and biological functions of resveratrol and summarizes the application of dietary resveratrol in animal production up to the present,including pigs,poultry,and ruminants.In pigs,dietary resveratrol improved intestinal health,mitochondrial function,meat quality,and more.In poultry,studies have shown that dietary resveratrol improves growth performance and meat and egg quality and alleviates heat stress induced adverse effects.There are few studies on dietary resveratrol in ruminants;however previous studies have indicated that dietary resveratrol increases nutrient digestibility and reduces methane emissions in sheep.It is hoped that this review could provide a specific theoretical basis and research ideas for the research and application of resveratrol. 展开更多
关键词 Animal production Biological function HEALTH PIGS POULTRY RESVERATROL RUMINANTS
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On Enforcing Dyadic-type Homogeneous Binary Function Product Constraints in MatBase
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作者 Christian Mancas 《Journal of Computer Science Research》 2024年第1期31-42,共12页
Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered... Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered and enforced by the software applications managing such data to guarantee plausibility.The(Elementary)Mathematical Data Model provides 17 types of dyadic-based homogeneous binary function product constraint categories.MatBase,an intelligent data and knowledge base management system prototype,allows database designers to simply declare them by only clicking corresponding checkboxes and automatically generates code for enforcing them.This paper describes the algorithms that MatBase uses for enforcing all 17 types of homogeneous binary function product constraint,which may also be employed by developers without access to MatBase. 展开更多
关键词 Database constraints Homogeneous binary function products Dyadic relations Modelling as programming The(Elementary)Mathematical Data Model MatBase
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Appropriateness of Reduced Modified Three-Parameter Weibull Distribution Function for Predicting Gold Production in Ghana
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作者 Samuel Kwaku Obeng Christiana C. Nyarko +1 位作者 Lewis Brew Kaku Sagary Nokoe 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期534-566,共33页
Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturall... Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturally follows. It is even more appropriate to have a model(s) with few predictor variables. This paper seeks to identify appropriate statistical distribution functions for fitting gold production in Ghana. The empirical paper relied mainly on quarterly secondary datasets on gold production between the years 2009 and 2022 secured from the Minerals Commission of Ghana, Accra. Several known statistical distributions including Weibull, Log-Normal, Generalized Extreme Value (GEV) were explored with Maximum Likelihood Estimation (MLE) and evaluated using model selection criteria as AIC, AICc and BIC. Goodness of Fits were evaluated using Kolmogorov-Smirnov Test (K-S), Cramer-Von Mises Statistic and Anderson-Darling Statistic. Based on the analysis conducted, the reduced modified 3-parameter Weibull distribution provided the best fit for gold production in Ghana. Though the reduced modified Weibull function is proposed, it is important however to recognize that other external factors can influence production levels. Also, the average quarterly fitted gold production is 1000334.8918 ± 75,327.080 (±7.5%) [i.e., 925,007.812 – 1,075,661.972]. This indicates that the average annually fitted gold production lies between 3700031.248 and 4302647.888 ounces at 99.9% confidence level. Therefore, the predicted gold production for the year 2022 is 3.7million ounces at 99.9% confidence level. 展开更多
关键词 Gold production Statistical Distribution functions Goodness of Fit Statistics
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Appropriateness of Reduced Modified Three-Parameter Weibull Distribution Function for Predicting Gold Production in Ghana
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作者 Samuel Kwaku Obeng Christiana C. Nyarko +1 位作者 Lewis Brew Kaku Sagary Nokoe 《Open Journal of Statistics》 2023年第4期534-566,共33页
Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturall... Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturally follows. It is even more appropriate to have a model(s) with few predictor variables. This paper seeks to identify appropriate statistical distribution functions for fitting gold production in Ghana. The empirical paper relied mainly on quarterly secondary datasets on gold production between the years 2009 and 2022 secured from the Minerals Commission of Ghana, Accra. Several known statistical distributions including Weibull, Log-Normal, Generalized Extreme Value (GEV) were explored with Maximum Likelihood Estimation (MLE) and evaluated using model selection criteria as AIC, AICc and BIC. Goodness of Fits were evaluated using Kolmogorov-Smirnov Test (K-S), Cramer-Von Mises Statistic and Anderson-Darling Statistic. Based on the analysis conducted, the reduced modified 3-parameter Weibull distribution provided the best fit for gold production in Ghana. Though the reduced modified Weibull function is proposed, it is important however to recognize that other external factors can influence production levels. Also, the average quarterly fitted gold production is 1000334.8918 ± 75,327.080 (±7.5%) [i.e., 925,007.812 – 1,075,661.972]. This indicates that the average annually fitted gold production lies between 3700031.248 and 4302647.888 ounces at 99.9% confidence level. Therefore, the predicted gold production for the year 2022 is 3.7million ounces at 99.9% confidence level. 展开更多
关键词 Gold production Statistical Distribution functions Goodness of Fit Statistics
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Association of polymorphisms of Nramp1 gene with immune function and production performance of large white pig 被引量:12
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作者 Hongmei Wu Duxue Cheng Lixian Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第2期91-95,共5页
The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl (Nrampl) with some immune function and the production performance in Large White pig. T... The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl (Nrampl) with some immune function and the production performance in Large White pig. The PCR-RFLP technique was applied to analyze the correlation between the polymorphisms of Nrampl gene and immune function [value of Polymorphonuclear Leukocytes (PMN) obtained by Nitroblue Tetrazolium (NBT) Reduction and effect of Cytotoxin in Monocyte] and production performance in 165 Large White pigs. The results showed that there was one Nde I restriction locus in Large White pig, and both values of PMN by NBT Reduction and effect of Cytotoxin in Monocyte in genotype BB were higher than those in genotype AB (P〈0.05). Simultaneously, the weight of 180-day-old pigs with genotype BB was higher than that with genotype AB (P〈0.05). The results indicated that there was a significant correlation between different genotypes of Nrampl gene and Immune function and production performance, and it can be regarded as a candidate gene of disease resistance. All these results provide valuable reference to further studies of pig disease resistance. 展开更多
关键词 Large White pig Nrampl gene immune function production performance
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ON THE GRAPHS OF PRODUCTS OF CONTINUOUS FUNCTIONS AND FRACTAL DIMENSIONS
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作者 刘佳 石赛赛 张远 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2483-2492,共10页
In this paper,we consider the graph of the product of continuous functions in terms of Hausdorff and packing dimensions.More precisely,we show that,given a real number 1≤β≤2,any real-valued continuous function in C... In this paper,we consider the graph of the product of continuous functions in terms of Hausdorff and packing dimensions.More precisely,we show that,given a real number 1≤β≤2,any real-valued continuous function in C([0,1])can be decomposed into a product of two real-valued continuous functions,each having a graph of Hausdorff dimensionβ.In addition,a product decomposition result for the packing dimension is obtained.This work answers affirmatively two questions raised by Verma and Priyadarshi[14]. 展开更多
关键词 Hausdorff dimension packing dimension graph of function product of functions
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An Application of Non–Linear Cobb-Douglas Production Function to Selected Manufacturing Industries in Bangladesh 被引量:3
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作者 Md. Moyazzem Hossain Ajit Kumar Majumder Tapati Basak 《Open Journal of Statistics》 2012年第4期460-468,共9页
Recently, businessmen as well as industrialists are very much concerned about the theory of firm in order to make correct decisions regarding what items, how much and how to produce them. All these decisions are direc... Recently, businessmen as well as industrialists are very much concerned about the theory of firm in order to make correct decisions regarding what items, how much and how to produce them. All these decisions are directly related with the cost considerations and market situations where the firm is to be operated. In this regard, this paper should be helpful in suggesting the most suitable functional form of production process for the major manufacturing industries in Bangladesh. This paper considers Cobb-Douglas (C-D) production function with additive error and multiplicative error term. The main purpose of this paper is to select the appropriate Cobb-Douglas production model for measuring the production process of some selected manufacturing industries in Bangladesh. We use different model selection criteria to compare the Cobb-Douglas production function with additive error term to Cobb-Douglas production function with multiplicative error term. Finally, we estimate the parameters of the production function by using optimization subroutine. 展开更多
关键词 COBB-DOUGLAS production function NEWTON-RAPHSON Method MANUFACTURING INDUSTRY BANGLADESH
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Proof of Riemann Conjecture Based on Contradiction between Xi-Function and Its Product Expression
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作者 Chuanmiao Chen 《Advances in Pure Mathematics》 2023年第7期463-472,共10页
Riemann proved three results: analytically continue ζ(s) over the whole complex plane s =σ + it with a pole s =1;(Theorem A) functional equation ξ(t) = G(s<sub>0</sub>)ζ (s<sub>0</sub>), s&... Riemann proved three results: analytically continue ζ(s) over the whole complex plane s =σ + it with a pole s =1;(Theorem A) functional equation ξ(t) = G(s<sub>0</sub>)ζ (s<sub>0</sub>), s<sub>0</sub> =1/2 + it and (Theorem B) product expression ξ<sub>1</sub>(t) by all roots of ξ(t). He stated Riemann conjecture (RC): All roots of ξ (t) are real. We find a mistake of Riemann: he used the same notation ξ(t) in two theorems. Theorem B must contain complex roots;it conflicts with RC. Thus theorem B can only be used by contradiction. Our research can be completed on s<sub>0</sub> =1/2 + it. Using all real roots r<sub>k</sub><sub> </sub>and (true) complex roots z<sub>j</sub> = t<sub>j</sub> + ia<sub>j</sub> of ξ (z), define product expressions w(t), w(0) =ξ(0) and Q(t) > 0, Q(0) =1 respectively, so ξ<sub>1</sub>(t) = w(t)Q(t). Define infinite point-set L(ω) = {t : t ≥10 and |ζ(s<sub>0</sub>)| =ω} for small ω > 0. If ξ(t) has complex roots, then ω =ωQ(t) on L(ω). Finally in a large interval of the first module |z<sub>1</sub>|>>1, we can find many points t ∈ L(ω) to make Q(t) . This contraction proves RC. In addition, Riemann hypothesis (RH) ζ for also holds, but it cannot be proved by ζ. 展开更多
关键词 Riemann Conjecture Xi-function functional Equation product Expression Multiplicative Group CONTRADICTION
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Application of Non-Linear Cobb-Douglas Production Function with Autocorrelation Problem to Selected Manufacturing Industries in Bangladesh 被引量:1
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作者 Md. Moyazzem Hossain Tapati Basak Ajit Kumar Majumder 《Open Journal of Statistics》 2013年第3期173-178,共6页
In developing counties, efficiency of economic development has been determined by the analysis of industrial production. An examination of the characteristic of industrial sector is an essential aspect of growth studi... In developing counties, efficiency of economic development has been determined by the analysis of industrial production. An examination of the characteristic of industrial sector is an essential aspect of growth studies. The growth of a country can be measured by Gross Domestic Product (GDP). GDP is substantially affected by the industrial output. Industrial gross output is mainly a function of capital and labor input. If the effect of labor and capital input to output is at a satisfactory level in an industry or in a group of industries, then industrial investment will increase. As a result, the number of industries will increase, which will directly affect GDP and also will decrease the unemployment rate. This is why, industrial input-output relationship is so important for any industry as well as for the overall industrial sector of a country. To forecast the production of a firm is necessary to identify the appropriate model. MD. M. Hossain et al. [1] have shown that Cobb-Douglas production function with additive errors was more suitable for some selected manufacturing industries in Bangladesh. The main purpose of this paper is to detect the autocorrelation problem of Cobb-Douglas production model with additive errors. The result shows that autocorrelation is presented in some manufacturing industries. Finally, this paper removes the autocorrelation problem and re-estimates the parameters of the Cobb- Douglas production function with additive errors. 展开更多
关键词 COBB-DOUGLAS production function AUTOCORRELATION MANUFACTURING Industry BANGLADESH
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Application Effect of Functional Microbial Products in the Cultivation of Green Ecological Strawberry
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作者 Houjun HE Shuwei YAO +2 位作者 Defu LI Muxiang JI Yushan QIAO 《Asian Agricultural Research》 2023年第2期46-47,54,共3页
In order to promote the transformation and high-quality development of strawberry industry and speed up the application of functional microbial products in strawberry,the application technology of functional microbial... In order to promote the transformation and high-quality development of strawberry industry and speed up the application of functional microbial products in strawberry,the application technology of functional microbial products in strawberry planting is studied and summarized.It mainly includes:the periods and methods of continuous cropping strawberry soil reduction and disinfection at high temperature,before and after strawberry planting,before plastic film mulching and whole process of plant spraying.Through multi-point test and demonstration,the purpose of advancing the season of strawberries,improving the quality,increasing production and increasing efficiency is achieved,and there is no risk of agricultural residue pollution,which meets the needs of people's consumption upgrading.Therefore,the application of functional microbial products in green ecological planting is very necessary,and it is worth further speeding up the demonstration and promotion. 展开更多
关键词 functional microbial products Strawberry cultivation Application effect
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Grain production space reconstruction and land system function tradeoffs in China 被引量:2
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作者 Fei Li Zhangxuan Qin +4 位作者 Xiaolin Liu Zehui Chen Xiaoli Wei Qiumeng Zhang Min Lei 《Geography and Sustainability》 2021年第1期22-30,共9页
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve... Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis. 展开更多
关键词 Land system function TRADEOFFS SYNERGY Grain production space reconstruction Set Pair Analysis
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Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm 被引量:1
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作者 Qi-Hong Feng Shan-Shan Li +2 位作者 Xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2879-2894,共16页
Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.T... Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development. 展开更多
关键词 Well production Optimization efficiency Streamline simulation Streamline feature Objective function Bayesian adaptive direct search algorithm
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Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens
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作者 Lianhua Zhang Junwei Ge +7 位作者 Fei Gao Min Yang Hui Li Fei Xia Hongtong Bai Xiangshu Piao Zhiying Sun Lei Shi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期295-312,共18页
Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not be... Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically studied.This study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(P<0.05)Haugh unit and n-6/n-3 of egg yolk,serum superoxide dismutase(SOD)compared with CON.No significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 groups.Compared with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and 56.Compared with CON,RE supplementation decreased(P<0.05)total cholesterol(TC)level.CTC,RE100 and RE200 decreased(P<0.05)serum interleukin-6(IL-6)content compared with CON.CTC and RE200 increased jejunal m RNA expression of ZO-1 and Occludin compared with CON.The biomarkers of cecal microbiota and metabolite induced by RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely associated with Haugh unit,n-6/n-3,SOD,IL-6,and TC.PICRUSt2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co A-transferase.Moreover,transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal magnum.Conclusions Dietary supplementation with 200 mg/kg RE could increase egg quality of late-phase laying hens via modulating intestinal barrier,cecal microbiota and metabolism,and oviductal function.Overall,RE could be used as a promising feed additive to improve egg quality of laying hens at late stage of production. 展开更多
关键词 Intestinal health Laying hens MICROBIOTA Oviductal function PHYTOCHEMICALS production
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Product quality prediction based on RBF optimized by firefly algorithm
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作者 HAN Huihui WANG Jian +1 位作者 CHEN Sen YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期105-117,共13页
With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality pred... With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality prediction models have many disadvantages,such as high complexity and low accuracy.To overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data distribution.Then the RBFFALFM is used to predict product quality.Comprehensive expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality. 展开更多
关键词 product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm
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Effects of Lactobacillus Microecologics on Production Performance, Immune Function and Intestinal Microflora of Egg Chicks
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作者 Xiao Jianshe Pan Huiqing Zhang Yanda 《Animal Husbandry and Feed Science》 CAS 2019年第3期103-106,共4页
[Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were... [Objective]The paper was to study the effects of lactobacillus microecologics on production performance,immune function and intestinal microflora of egg chicks.[Method]Totally 18001-day-old chicks of Hyline brown were randomly divided into three groups,four repeats each group and 150 chicks each repeat.The chicks in control group were supplied with basic diet,and those in experimental groups I and II were supplied with the basic diet added with 100 and 150 g/t microecologics,respectively.[Result]Compared with the control group,the daily gain of egg chicks in experimental group II after 7 weeks was increased by 3.67%(P<0.05),and the feed conversion ratio was significantly reduced by 0.05(P<0.05);the thymus indexes in experimental groups I and II were significantly improved by 4.95%and 5.94%(P<0.05),and the spleen indexes were significantly improved by 3.32% and 4.36% compared with the control group(P<0.05).The index of bursa of fabricius in experimental group II was extremely improved by 9.66%compared with the control group(P<0.01).Meantime,experimental group II extremely improved the number of living lactobacillus in caecum of egg chicks(P<0.01),and extremely reduced the number of Escherichia coli in caecum(P<0.01).[Conclusion]Lactobacillus microecologics are beneficial to the improvement of production performance,immune function and intestinal flora of egg chicks.The optimal addition amount in the feed of chicks is 150 g/t. 展开更多
关键词 LACTOBACILLUS microecologics EGG CHICK production performance Immune function Intestinal MICROFLORA
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Efficient Frontier via Production Functions and Mechanization
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作者 Hideki Nakamura 《American Journal of Operations Research》 2017年第1期56-63,共8页
This study attempts to reconcile data envelopment analysis (DEA) with the production function approach in economics. We examine not only the inputs of capital and labor, but also the ranges of these inputs in producti... This study attempts to reconcile data envelopment analysis (DEA) with the production function approach in economics. We examine not only the inputs of capital and labor, but also the ranges of these inputs in production process steps, and endogenously derive a Leontief production function. The Leontief production functions shift northeasterly owing to mechanization, which is the replacement of labor inputs by capital inputs in some steps. Consequently, we describe the efficient frontier as the convex hull of the Leontief production functions. Furthermore, we consider the possibility of efficient production below the efficient frontier. 展开更多
关键词 production Process STEPS Leontief production function MECHANIZATION EFFICIENT FRONTIER production below the EFFICIENT FRONTIER
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Saline Water Irrigation Scheduling Through a Crop-Water-Salinity Production Function and a Soil-Water-Salinity Dynamic Model 被引量:16
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作者 WANG Yang-Ren KANG Shao-Zhong +2 位作者 LI Fu-Sheng ZHANG Lu ZHANG Jian-Hua 《Pedosphere》 SCIE CAS CSCD 2007年第3期303-317,共15页
Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to o... Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water. 展开更多
关键词 土壤水盐生成函数 土壤水盐动态模型 盐水灌溉 调度
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The Estimation Methods for Agricultural Surplus Labor Based on Stochastic Frontier Production Function 被引量:2
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作者 Chaozhou LU Yanfen LUO 《Asian Agricultural Research》 2014年第6期61-65,共5页
The existing calculation methods for the number of agricultural surplus labor have a common flaw,that is,they can not reflect the impact of technical efficiency changes in agricultural production on the surplus labor.... The existing calculation methods for the number of agricultural surplus labor have a common flaw,that is,they can not reflect the impact of technical efficiency changes in agricultural production on the surplus labor. Based on the basic principle of stochastic frontier production function,this paper calculates the agricultural production technical efficiency of various provinces,and selects the province with the highest technical efficiency to assume that its agricultural labor is fully utilized,and there is no agricultural surplus labor. With the ratio of agricultural labor number to agricultural output value in this province as a reference,this paper calculates the number of agricultural surplus labor in other provinces. This calculation method makes up for the shortcomings of the existing calculation methods; it reflects the relationship between the number of agricultural surplus labor and production technical efficiency. 展开更多
关键词 AGRICULTURAL SURPLUS LABOR STOCHASTIC FRONTIER PRO
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A Basic Method of Constructing Production Functions
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作者 Guo Yaohuang Wang Yaping Zhang Wel(School of Economics and Management,Soultwest Jiaotong University), Chengdu 610031,China 《Journal of Modern Transportation》 1995年第2期127-132,共6页
In this paper,a new basic method of constructing smooth production functions isgiven,and many ordinary production functions are drawn. It is obvious thatsome more production functions can be obtained from the method.
关键词 production function continuously differentiable function homogeneousfunction
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Delimitation of Grain Production Functional Zones:An Empirical Analysis of Fangzi District in Weifang City
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作者 Shouhua LI Yujiao ZHANG Shuying HOU 《Asian Agricultural Research》 2021年第12期5-8,共4页
To solve some unreasonable problems in the acceptance process of the delimitation project of grain production functional zones,the acceptance results of grain production functional zones in Fangzi District,Weifang Cit... To solve some unreasonable problems in the acceptance process of the delimitation project of grain production functional zones,the acceptance results of grain production functional zones in Fangzi District,Weifang City were elaborated from the aspects of the third party organization,inspectors,expert group,acceptance criteria,acceptance method,acceptance contents,etc.,and the overall performance of the project was reviewed.The problems that need to be rectified during the implementation of the project were put forward,and the irrationality of the acceptance and the places that need to be improved were pointed out,which would provide a better guiding value for the delimitation of grain production functional zone and the acceptance and performance evaluation of similar projects. 展开更多
关键词 Grain production functional zones DELIMITATION ACCEPTANCE REPORT
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