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Effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in type 2 diabetes:A systematic review
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作者 Christos Kourek Eleftherios Karatzanos +4 位作者 Vasiliki Raidou Ourania Papazachou Anastassios Philippou Serafim Nanas Stavros Dimopoulos 《World Journal of Cardiology》 2023年第4期184-199,共16页
BACKGROUND Type 2 diabetes mellitus(T2DM)is a chronic metabolic syndrome characterized by insulin resistance and hyperglycemia that may lead to endothelial dysfunction,reduced functional capacity and exercise intolera... BACKGROUND Type 2 diabetes mellitus(T2DM)is a chronic metabolic syndrome characterized by insulin resistance and hyperglycemia that may lead to endothelial dysfunction,reduced functional capacity and exercise intolerance.Regular aerobic exercise has been promoted as the most beneficial non-pharmacological treatment of cardiovascular diseases.High intensity interval training(HIIT)seems to be superior than moderate-intensity continuous training(MICT)in cardiovascular diseases by improving brachial artery flow-mediated dilation(FMD)and cardiorespiratory fitness to a greater extent.However,the beneficial effects of HIIT in patients with T2DM still remain under investigation and number of studies is limited.AIM To evaluate the effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in patients with T2DM.METHODS We performed a search on PubMed,PEDro and CINAHL databases,selecting papers published between December 2012 and December 2022 and identified published randomized controlled trials(RCTs)in the English language that included community or outpatient exercise training programs in patients with T2DM.RCTs were assessed for methodological rigor and risk of bias via the Physiotherapy Evidence Database(PEDro).The primary outcome was peak VO_(2 ) and the secondary outcome was endothelial function assessed either by FMD or other indices of microcirculation.RESULTS Twelve studies were included in our systematic review.The 12 RCTs resulted in 661 participants in total.HIIT was performed in 310 patients(46.8%),MICT to 271 and the rest 80 belonged to the control group.Peak VO_(2 ) increased in 10 out of 12 studies after HIIT.Ten studies compared HIIT with other exercise regimens(MICT or strength endurance)and 4 of them demonstrated additional beneficial effects of HIIT over MICT or other exercise regimens.Moreover,4 studies explored the effects of HIIT on endothelial function and FMD in T2DM patients.In 2 of them,HIIT further improved endothelial function compared to MICT and/or the control group while in the rest 2 studies no differences between HIIT and MICT were observed.CONCLUSION Regular aerobic exercise training has beneficial effects on cardiorespiratory fitness and endothelial function in T2DM patients.HIIT may be superior by improving these parameters to a greater extent than MICT. 展开更多
关键词 Type 2 diabetes mellitus EXERCISE High intensity interval training Cardiorespiratory fitness Peak VO_(2) Endothelial function
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Fitness of Four-Parameter Beta Distribution Function for Forecasting Gold Reserve and Its Production Lifespan in Ghana
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作者 Samuel Kwaku Obeng Christiana C. Nyarko +1 位作者 Lewis Brew K. Sagary Nokoe 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期567-593,共27页
Ghana, renowned for its abundant gold reserves, plays a significant role in the global mining industry. Effective management and accurate forecasting of these reserves are vital for sustainable resource utilization an... Ghana, renowned for its abundant gold reserves, plays a significant role in the global mining industry. Effective management and accurate forecasting of these reserves are vital for sustainable resource utilization and economic planning. Forecasting gold reserves and estimating their production lifespan are complex tasks that require robust statistical models capable of capturing the underlying dynamics of gold deposit accumulation and extraction. To this end, the four-parameter Beta distribution function emerges as a promising candidate due to its flexibility and ability to handle non-negative data. This research aims to investigate the fitness and applicability of the four-parameter Beta distribution function for forecasting Ghana’s gold reserves and estimating the production lifespan of this precious resource. The empirical paper relied mainly on quarterly secondary datasets on gold reserve between the years 2009 and 2022 secured from the Minerals Commission of Ghana, Accra. Several known statistical distributions including Beta, Weibull, Normal, Logistic and Gamma were explored with Maximum Likelihood Estimation (MLE) and evaluated using model selection criteria as AIC 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 four-parameter Beta distribution provided the best fit for gold reserve in Ghana. At a 99.9% confidence level and considering the current annual average gold production estimate of 3,700,031.248 to 4,302,647.888 ounces, the projected lifespan of gold production in Ghana extends to the year 1,953,765. This astounding estimate suggests that the country’s gold reserves are expected to sustain production for an extended period, providing a critical resource for economic development and supporting the mining industry well into the distant future. 展开更多
关键词 Gold Reserve Four-Parameter Beta Distribution function Goodness of fit Statistics
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Fitness of Four-Parameter Beta Distribution Function for Forecasting Gold Reserve and Its Production Lifespan in Ghana
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作者 Samuel Kwaku Obeng Christiana C. Nyarko +1 位作者 Lewis Brew K. Sagary Nokoe 《Open Journal of Statistics》 2023年第4期567-593,共27页
Ghana, renowned for its abundant gold reserves, plays a significant role in the global mining industry. Effective management and accurate forecasting of these reserves are vital for sustainable resource utilization an... Ghana, renowned for its abundant gold reserves, plays a significant role in the global mining industry. Effective management and accurate forecasting of these reserves are vital for sustainable resource utilization and economic planning. Forecasting gold reserves and estimating their production lifespan are complex tasks that require robust statistical models capable of capturing the underlying dynamics of gold deposit accumulation and extraction. To this end, the four-parameter Beta distribution function emerges as a promising candidate due to its flexibility and ability to handle non-negative data. This research aims to investigate the fitness and applicability of the four-parameter Beta distribution function for forecasting Ghana’s gold reserves and estimating the production lifespan of this precious resource. The empirical paper relied mainly on quarterly secondary datasets on gold reserve between the years 2009 and 2022 secured from the Minerals Commission of Ghana, Accra. Several known statistical distributions including Beta, Weibull, Normal, Logistic and Gamma were explored with Maximum Likelihood Estimation (MLE) and evaluated using model selection criteria as AIC 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 four-parameter Beta distribution provided the best fit for gold reserve in Ghana. At a 99.9% confidence level and considering the current annual average gold production estimate of 3,700,031.248 to 4,302,647.888 ounces, the projected lifespan of gold production in Ghana extends to the year 1,953,765. This astounding estimate suggests that the country’s gold reserves are expected to sustain production for an extended period, providing a critical resource for economic development and supporting the mining industry well into the distant future. 展开更多
关键词 Gold Reserve Four-Parameter Beta Distribution function Goodness of fit Statistics
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Thermodynamic Fit Functions of the Two-Phase Fluid and Critical Exponents 被引量:1
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作者 Albrecht Elsner 《Engineering(科研)》 2014年第12期789-826,共38页
Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series ... Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series expansion about the critical point. The leading term with the critical exponent dominates the temperature variation between the critical and triple points. With β being introduced as the critical exponent for the difference between liquid and vapor densities, it is shown that the critical exponent of each fit function depends (if at all) on β. In particular, the critical exponent of the reciprocal heat capacity c﹣1 is α=1-2β and those of the entropy s and internal energy u are?2β, while that of the reciprocal isothermal compressibility?κ﹣1T is γ=1. It is thus found that in the case of the two-phase fluid the Rushbrooke equation conjectured α +?2β + γ=2 combines the scaling laws resulting from the two relations c=du/dT and?κT=dlnρ/dp. In the context with c, the second temperature derivatives of the chemical potential μ and vapor pressure p are investigated. As the critical point is approached, ﹣d2μ/dT2 diverges as c, while?d2p/dT2 converges to a finite limit. This is explicitly pointed out for the two-phase fluid, water (with β=0.3155). The positive and almost vanishing internal energy of the one-phase fluid at temperatures above and close to the critical point causes conditions for large long-wavelength density fluctuations, which are observed as critical opalescence. For negative values of the internal energy, i.e. the two-phase fluid below the critical point, there are only microscopic density fluctuations. Similar critical phenomena occur when cooling a dilute gas to its Bose-Einstein condensate. 展开更多
关键词 CRITICAL Condition U = 0 CRITICAL OPALESCENCE Rushbrooke Equation THERMODYNAMIC fit functions for Saturated Water Vapor and Liquid Volumes Vapor Pressure Chemical Potential Entropy Internal ENERGY Free ENERGY Heat Capacity
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Large Scattered Data Fitting Based on Radial Basis Functions 被引量:2
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作者 FENG Ren-zhong XU Liang 《Computer Aided Drafting,Design and Manufacturing》 2007年第1期66-72,共7页
Solving large radial basis function (RBF) interpolation problem with non-customized methods is computationally expensive and the matrices that occur are typically badly conditioned. In order to avoid these difficult... Solving large radial basis function (RBF) interpolation problem with non-customized methods is computationally expensive and the matrices that occur are typically badly conditioned. In order to avoid these difficulties, we present a fitting based on radial basis functions satisfying side conditions by least squares, although compared with interpolation the method loses some accuracy, it reduces the computational cost largely. Since the fitting accuracy and the non-singularity of coefficient matrix in normal equation are relevant to the uniformity of chosen centers of the fitted RBE we present a choice method of uniform centers. Numerical results confirm the fitting efficiency. 展开更多
关键词 scattered data radial basis functions interpolation least squares fitting uniform centers
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 被引量:2
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients PIECEWISE POLYNOMIAL functions CUBIC splines Curve fitting PIECEWISE linear functions PIECEWISE CUBIC HERMITE interpolating POLYNOMIAL PROJECTILE modelling and simulation Fire control inputs Precision Ballistic computer software
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Function fitting for modeling seasonal normalized difference vegetation index time series and early forecasting of soybean yield 被引量:2
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作者 Alexey Stepanov Konstantin Dubrovin Aleksei Sorokin 《The Crop Journal》 SCIE CSCD 2022年第5期1452-1459,共8页
Forecasting crop yields based on remote sensing data is one of the most important tasks in agriculture.Soybean is the main crop in the Russian Far East.It is desirable to forecast soybean yield as early as possible wh... Forecasting crop yields based on remote sensing data is one of the most important tasks in agriculture.Soybean is the main crop in the Russian Far East.It is desirable to forecast soybean yield as early as possible while maintaining high accuracy.This study aimed to investigate seasonal time series of the normalized difference vegetation index(NDVI) to achieve early forecasting of soybean yield.This research used data from the Moderate Resolution Image Spectroradiometer(MODIS),an arable-land mask obtained from the VEGA-Science web service,and soybean yield data for 2008-2017 for the Jewish Autonomous Region(JAR) districts.Four approximating functions were fitted to model the NDVI time series:Gaussian,double logistic(DL),and quadratic and cubic polynomials.In the period from calendar weeks 22-42(end of May to mid-October),averaged over two districts,the model using the DL function showed the highest accuracy(mean absolute percentage error-4.0%,root mean square error(RMSE)-0.029,P <0.01).The yield forecast accuracy of prediction in the period of weeks 25-30 in JAR municipalities using the parameters of the Gaussian function was higher(P <0.05) than that using the other functions.The mean forecast error for the Gaussian function was 14.9% in week 25(RMSE was0.21 t ha) and 5.1%-12.9% in weeks 26-30(RMSE varied from 0.06 to 0.15 t ha) according to the2013-2017 data.In weeks 31-32,the error was 5.0%-5.4%(RMSE was 0.07 t ha) using the Gaussian parameters and 7.4%-7.7%(RMSE was 0.09-0.11 t ha) for the DL function.When the method was applied to municipal districts of other soy-producing regions of the Russian Far East.RMSE was0.14-0.32 t hain weeks 25-26 and did not exceed 0.20 t hain subsequent weeks. 展开更多
关键词 NDVI function fitting Early prediction YIELD SOYBEAN
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The Application of Multiquadric Function Fitting to Borehole Strain Time Series Data Processing 被引量:1
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作者 Peng Zhao Zhang Lei +1 位作者 Chen Zhiyao Lv Pingji 《Earthquake Research in China》 CSCD 2017年第2期239-246,共8页
Based on the existing continuous borehole strain observation,the multiquadric function fitting method was used to deal with time series data. The impact of difference kernel function parameters was discussed to obtain... Based on the existing continuous borehole strain observation,the multiquadric function fitting method was used to deal with time series data. The impact of difference kernel function parameters was discussed to obtain a valuable fitting result,from which the physical connotation of the original data and its possible applications were analyzed.Meanwhile,a brief comparison was made between the results of multiquadric function fitting and polynomial fitting. 展开更多
关键词 Multiquadric function fitting Kernel function Borehole strain time series
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GENETIC ALGORITHM WITH FUZZY FITNESS EVALUATION
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作者 Huang Jianjun(1105 Lab., Northwestern Polytechnical University, Xi’an, 710072)Xie Weixin (202 Lab. , School of Electronic Engineering, Xidian University, Xi’an, 710071) 《Journal of Electronics(China)》 1998年第3期254-258,共5页
Using a fuzzy estimator to evaluate the fitness of chromosomes in a genetic algorithm and adaptively training it in the evolutionary process, the genetic algorithm with fuzzy fitness evaluation is proposed to reduce t... Using a fuzzy estimator to evaluate the fitness of chromosomes in a genetic algorithm and adaptively training it in the evolutionary process, the genetic algorithm with fuzzy fitness evaluation is proposed to reduce the computation time of the algorithm. An analysis on the optimization performance of the proposed algorithm shows that it maintains good performance with its computation time saved. Finally, simulation results on design of a fuzzy controller are presented. 展开更多
关键词 FUZZY evaluation fitness function GENETIC algorithm COMPUTATION time
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Physical activity,fitness and all-cause mortality:An 18-year follow-up among old people
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作者 Marja ?ij? Markku Kauppinen +1 位作者 Urho M.Kujala Terttu Parkatti 《Journal of Sport and Health Science》 SCIE 2016年第4期437-442,共6页
Background:Little is known about change in physical activity(PA) and its relationship to all-cause mortality among old people.There is even less information about the association between PA,fitness and all-cause mo... Background:Little is known about change in physical activity(PA) and its relationship to all-cause mortality among old people.There is even less information about the association between PA,fitness and all-cause mortality among people aged 80 years and above.The objective is to investigate persistence and change in PA over 5 years as a predictor of all-cause mortality,and fitnes as a mediator of this association,among people aged 80 and 85 years at the beginning of an 18-year mortality follow-up period.Methods:Using Evergreen Project data(started in 1989),4 study groups were formed according to self-reported changes in PA level,over a 5-year period(starting in 1989–1990 and ending in 1994–1995):remained active(RA,control group),changed to inactive(CI),remained inactive(RI),and changed to active(CA).Mortality was followed up over the 18-year period(1994–2012).Cox models with different covariates such as age,sex,use of alcohol,smoking,chronic diseases,and a 10 m walking test were used to analyze the association between change in PA level and mortality.Results:Compared to RA,those who decreased their PA level(CI) between baseline and follow-up had higher all-cause mortality(hazard ratio(HR=2.09;95%CI:1.63–2.69) when adjusted for age,gender,and chronic diseases.RI showed the highest all-cause mortality(HR = 2.16;95%CI:1.59–2.93).In CA,when compared against RA,the risk of all-cause mortality was not statistically significan(HR=1.51;95%CI:0.95–2.38).In comparison with RA,when walking speed over 10 m was added as a covariate,all-cause mortality risk was almost statistically significan only in CI(HR=1.37;95%CI:1.00–1.87).Conclusion:Persistence and change in PA level was associated with mortality.This association was largely explained by fitnes status.Randomized controlled studies are needed to test whether maintaining or increasing PA level could lengthen the life of old people. 展开更多
关键词 All-cause mortality fitness Follow-up study functional ability Old people Physical activity
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Fitness Age Score and the Risk of Long-Term Care Insurance Certification—The Kyoto-Kameoka Longitudinal Study
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作者 Tsukasa Yoshida Misaka Kimura +7 位作者 Yosuke Yamada Keiichi Yokoyama Tatsuro Ishihara Yasuko Yoshinaka Aya Itoi Yuya Watanabe Noriyuki Kida Teruo Nomura 《Open Journal of Epidemiology》 2017年第2期190-200,共11页
Long-Term Care Insurance System has been introduced to provide appropriate care for the elderly who needs nursing care in Japan. Physical function is one of most important function for the elderly to live independentl... Long-Term Care Insurance System has been introduced to provide appropriate care for the elderly who needs nursing care in Japan. Physical function is one of most important function for the elderly to live independently. A previous study had established a Fitness Age Score (FAS) based on a theory for biomarker of aging. This study clarified whether the FAS could be used to predict the need for certification of long-term care (CLTC) in independent elderly people. We included 939 independent, community-dwelling-elderly (average age, 74.4 years) whose physical function was measured and for whom the CLTC was tracked for 24 months. The FAS comprised five physical fitness items: Walking time, grip strength, one-leg standing, vertical jump, and functional reach test. Based on the FAS, we calculated the odds ratio (OR) for the CLTC. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) was used for further analysis. We also used the Youden Index (YI), minimum distance method (MD), and two-graph ROC method (TG) to calculate cutoff values (CVs) for screening. We divided subjects into the low and high physical fitness group with CVs. We developed cumulative CLTC curves using the Kaplan-Meier method. Sixteen people could not be tracked for the full 24 months. The measurement of FAS was completed for 798 people, of whom 28 became CLTC. The measurement of FAS was not completed for 125 people, of whom 21 became CLTC. The CLTC OR for people with incomplete FAS was 5.553. The AUC was 0.72 (p < 0.001). The CVs for the FAS were -0.29 for YI (sensitivity, 92.9% and specificity, 40.4%), -1.23 for MD (57.1% and 73.4%), and -0.81 for TG (60.7% and 60.9%). The cumulative CLTC curves according to CVs all showed significant differences (p = 0.000 - 0.020). In conclusion, the FAS can be used to predict CLTC. 展开更多
关键词 ELDERLY Physical function Long-Term CARE Screening fitness Age SCORE (FAS)
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Differences in Body Composition and Physical Fitness in Elderly Men and Women
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作者 Zvonko Mlljkovic Goran Sporis +2 位作者 Zeljko Vukic Zoran Milanovic Sasa Pantelic 《Journal of Chemistry and Chemical Engineering》 2013年第6期560-565,共6页
The aim of this study was to determine differences in body composition and physical fitness in elderly men and women. Five hundred twenty six subjects were included in this study, 272 were men (52%) and 254 women (... The aim of this study was to determine differences in body composition and physical fitness in elderly men and women. Five hundred twenty six subjects were included in this study, 272 were men (52%) and 254 women (48%). To determine the trend of changes of anthropometric parameters and physical fitness in people aged over 60, the authors were divided subjects in 5 age groups: 60-64, 65-69, 70-74, 75-79 and over 80 years of age. Decrease in strength is observed with the aging process so that the respondents aged 60-64 years significantly differ in the strength of the lower extremities of elderly subjects 70-74 and 75-79 years of age. Also this difference is noticeable if they compare with men and women. In this study, they found that there was an increase in the amount of adipose tissue, reducing the level of muscle activity and decreased muscle strength and endurance of the aging process. 展开更多
关键词 Older people functional fitness REDUCTION body mass index.
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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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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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A Traceable Cancer Model: DNA Damage, Fragile Site-SMGs, Mitotic Slippage, 4n-Genome-Reduction to Fitness-Gained, Initiating, 2n First Cells 被引量:1
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作者 Kirsten H. Walen 《Journal of Cancer Therapy》 2021年第6期365-386,共22页
We have known since 1976 that cancer evolves clonally from one initiated<span style="font-family:;" "=""><span> normal human cell, the </span><i><span>first cell&... We have known since 1976 that cancer evolves clonally from one initiated<span style="font-family:;" "=""><span> normal human cell, the </span><i><span>first cell</span></i><span>. Today we see that this fact has been overshadowed from federal funding choice of the mutation theory (MT), which not yet has shown tumorigenesis-initiation in normal human cells. Our suggested, death signaled, stress model from time delayed S-period (replication slowness), causing repair instability from under-replicated lesions in repetitive DNAs, herein has the objective of revealing, significant literature support from a mini-review. We reasoned that early versus late S-period stress would </span><span>have different outcomes: early the slowness affecting mitotic slippage with</span> <span>diploid re-replication to 4n cells whereas late-S, with milder stress effect,</span><span> pro</span><span>ducing diploid cells. In cancer burden, near-half is diploid, but tetraploid</span><span> solid tumors have the attention. The initial 4n cells were special with orderly genomic reductive division to diploid first cells with measurable fitness-gain from hours-reduced total cell cycle time. Experimental data from Coxsakie-B3 virus infected normal fibroblasts, reiterated 4n cell production from </span><span>death-s</span><span>ignaled recovery-cells with progressive cell-phenotypic changes to polygon</span><span>al </span><span>and roundness cell-shapes, indistinguishable from diagnostic/prognostic </span><span>cancer </span><span>morphology. The 4n cells showed a self-inflicted 90</span></span><span style="font-family:;" "=""><span><span style="color:#4F4F4F;white-space:normal;background-color:#FFFFFF;"><span style="color:#4F4F4F;white-space:normal;background-color:#FFFFFF;">°</span></span></span><span> turn of the 4n nucleus</span></span><span style="font-family:;" "=""> <span>before division, affecting a perpendicular orientation of the fitness-gained</span><span> first cells relative to neighboring cells. In an illustrated cell cycle drawing with early and late S-period stress, it became clear that coding genes on borders of repair unstable satellite, repetitive DNA regions, could become mutated. We found these mutations to be tumor SMGs (significantly mutated genes). Evidential material was presented for loss of function genetics driving tumorigenesis to a parasitic lifestyle.</span></span> 展开更多
关键词 S-Period-DDR 2n-4n-90° Nuclear Turn Cytoskeleton/Cell Polarity Amitosis Time-Short Cell Cycle fitness-Gain ANEUPLOIDY Loss-of-function Genetics Parasitic-Tumor Life Therapy-Possibilities
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Polynomial Functions Composed of Terms with Non-Integer Powers
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作者 Serdar Beji 《Advances in Pure Mathematics》 2021年第10期791-806,共16页
Polynomial functions containing terms with non-integer powers are studied to disclose possible approaches for obtaining their roots as well as employing them for curve-fitting purposes. Several special cases represent... Polynomial functions containing terms with non-integer powers are studied to disclose possible approaches for obtaining their roots as well as employing them for curve-fitting purposes. Several special cases representing equations from different categories are investigated for their roots. Curve-fitting applications to physically meaningful data by the use of fractional functions are worked out in detail. Relevance of this rarely worked subject to solutions of fractional differential equations is pointed out and existing potential in related future work is emphasized. 展开更多
关键词 RATIONAL Irrational Imaginary and Transcendental Powers Roots of functions with Variables of Non-Integer Powers Curve-fitting by functions Incorporating Terms with Rational Powers Fractional Differential Equations
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新型冠状病毒感染后潜水员适潜性评估
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作者 官振标 董宇超 +4 位作者 徐佳骏 俞旭华 文宇坤 刘霞 刘文武 《海军军医大学学报》 CAS CSCD 北大核心 2024年第3期352-357,共6页
新型冠状病毒感染(COVID-19)对全身几乎所有器官都会产生影响,其中最主要的受累器官为肺和心脏。随着COVID-19康复患者数量不断增加,越来越多的证据表明,因COVID-19住院治疗获得康复的患者中有相当大比例的人群存在后遗症,主要表现为呼... 新型冠状病毒感染(COVID-19)对全身几乎所有器官都会产生影响,其中最主要的受累器官为肺和心脏。随着COVID-19康复患者数量不断增加,越来越多的证据表明,因COVID-19住院治疗获得康复的患者中有相当大比例的人群存在后遗症,主要表现为呼吸系统和心血管系统的症状。对于潜水员,COVID-19后的运动耐受、心肺功能的恢复对其适潜性具有重要影响。一些组织和机构发布了潜水员COVID-19后的适潜性评估指南。本文对COVID-19后的呼吸和心血管系统后遗症及相关的适潜性评估方案进行简要介绍,并基于已有的相关要求和我国实际,初步提出我国潜水员COVID-19后的适潜性评估要求。 展开更多
关键词 新型冠状病毒感染 适潜性 评估 肺功能 运动耐受 心功能
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改进蚁群算法的送餐机器人路径规划 被引量:3
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作者 蔡军 钟志远 《智能系统学报》 CSCD 北大核心 2024年第2期370-380,共11页
蚁群算法拥有良好的全局性、自组织性、鲁棒性,但传统蚁群算法存在许多不足之处。为此,针对算法在路径规划问题中的缺陷,在传统蚁群算法的状态转移公式中,引入目标点距离因素和引导素,加快算法收敛性和改善局部最优缺陷。在带时间窗的... 蚁群算法拥有良好的全局性、自组织性、鲁棒性,但传统蚁群算法存在许多不足之处。为此,针对算法在路径规划问题中的缺陷,在传统蚁群算法的状态转移公式中,引入目标点距离因素和引导素,加快算法收敛性和改善局部最优缺陷。在带时间窗的车辆路径问题(vehicle routing problem with time windows,VRPTW)上,融合蚁群算法和遗传算法,并将顾客时间窗宽度以及机器人等待时间加入蚁群算法状态转移公式中,以及将蚁群算法的解作为遗传算法的初始种群,提高遗传算法的初始解质量,然后进行编码,设置违反时间窗约束和载重量的惩罚函数和适应度函数,在传统遗传算法的交叉、变异操作后加入了破坏-修复基因的操作来优化每一代新解的质量,在Solomon Benchmark算例上进行仿真,对比算法改进前后的最优解,验证算法可行性。最后在餐厅送餐问题中把带有障碍物的仿真环境路径规划问题和VRPTW问题结合,使用改进后的算法解决餐厅环境下送餐机器人对顾客服务配送问题。 展开更多
关键词 蚁群算法 遗传算法 状态转移公式 适应度函数 引导素 局部最优 初始种群 时间窗约束 路径规划
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基于功能性体适能指标构建老年慢性阻塞性肺疾病患者的居家康复护理方案
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作者 李杰红 郑智 +2 位作者 王静 杨汀 赵帆 《实用临床医药杂志》 CAS 2024年第9期99-102,114,共5页
目的 基于功能性体适能指标构建老年慢性阻塞性肺疾病患者的居家康复护理方案。方法 通过文献检索、病例回顾,以及结合老年慢性阻塞性肺疾病患者日常生活需要、疾病特点、体适能等核心指标,构建老年慢性阻塞性肺疾病患者居家康复护理方... 目的 基于功能性体适能指标构建老年慢性阻塞性肺疾病患者的居家康复护理方案。方法 通过文献检索、病例回顾,以及结合老年慢性阻塞性肺疾病患者日常生活需要、疾病特点、体适能等核心指标,构建老年慢性阻塞性肺疾病患者居家康复护理方案初稿。编制专家函询问卷,并通过小组讨论,遴选出12名呼吸、康复相关专家,进行2轮专家函询。结果 2轮专家函询问卷回收率均为83.3%。专家权威系数为0.90。居家康复护理方案共有4个一级指标、11个二级指标和33个三级指标。结论 以功能性体适能指标构建的老年慢性阻塞性肺疾病患者居家康复护理方案具有可实施性、科学性、创新性,可为临床应用提供理论依据。 展开更多
关键词 功能性体适能 康复 老年 慢性阻塞性肺疾病 护理方案
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基于不确定性的多尺度暴雨强度和外江洪水位联合分布研究
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作者 王俊超 彭涛 刘佳明 《自然灾害学报》 CSCD 北大核心 2024年第3期39-55,共17页
城市洪涝治理方案以及排涝设施规模建设都与城市暴雨强度和外江洪水位息息相关,因此需要对暴雨强度与外江洪水位联合概率分布进行深入研究。以武汉市为例,采用Copula函数建立小时尺度城市暴雨强度和外江洪水位的联合分布,使用极大似然... 城市洪涝治理方案以及排涝设施规模建设都与城市暴雨强度和外江洪水位息息相关,因此需要对暴雨强度与外江洪水位联合概率分布进行深入研究。以武汉市为例,采用Copula函数建立小时尺度城市暴雨强度和外江洪水位的联合分布,使用极大似然估计值(Max-Likelihood)、模型选择准则、RMSE和NSE拟合优度来评估不同Copula模型的性能,利用局部优化(Local optimization,LO)和马尔科夫链蒙特卡洛(Markov chain Monte Carlo,MCMC)方法来分析Copula模型的不确定性。结果表明:暴雨强度和外江洪水位两要素存在明显的正相关,1 h最大连续降水量和最大日水位相关性最高,最优联合分布函数为Gumbel Copula函数;模型不确定性分析表明MCMC模拟的最优参数与理论参数值基本吻合,效果明显优于局部优化算法,且模型不确定性结果与拟合优度评价结果一致,进一步验证了联合分布函数参数的有效性。相同频率情况下,单变量值低于两变量联合频率对应的暴雨强度和外江洪水位值,高于两变量同现频率对应的暴雨强度和外江洪水位值;两变量同现重现期高于单变量设计重现期,而联合重现期低于单变量设计重现期。同频率下的暴雨强度与水位的组合风险率都远远低于单变量情况下的频率值,50 a以上排涝风险率大于设计暴雨重现期,但最大不超过联合风险率。 展开更多
关键词 COPULA函数 联合概率分布 拟合优度 联合重现期
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