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Change Point Analysis to Detect the Effect of Pruning Severity on Tree Growth
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作者 Yutaka Iguchi 《Open Journal of Forestry》 2024年第1期67-73,共7页
The effect of pruning severity on tree growth was analyzed by change point detection using segmented regression. The present study applied this analysis to a well-known published data set including diameter growth res... The effect of pruning severity on tree growth was analyzed by change point detection using segmented regression. The present study applied this analysis to a well-known published data set including diameter growth response, tree age, pruning severity and pretreatment crown size. First, multiple regression analysis was performed to assess the effect of tree age, pruning severity and pretreatment crown size on diameter growth response. Next, segmented regression analysis was performed to assess the effect of pruning severity on diameter growth response. The results of the multiple regression showed that diameter growth response was significantly influenced by pruning severity and pretreatment crown size. The results of the segmented regression showed that in the whole data set, an abrupt change toward a decrease in diameter growth response was detected at 25% of the live crown removed. However, in the group of fully crowned and open-grown, diameter growth response continuously decreased with increasing pruning severity with no significant abrupt change, whereas in the group of 70% - 90% live crown, diameter growth response did not significantly decrease up to the break point (53% crown removed) and then abruptly decreased. This may be the first study to show the numerical evaluation of the effect of pruning severity on tree growth by change point analysis. 展开更多
关键词 Regression analysis Crown Removal Limit Tree Growth PRETREATMENT Abrupt Change
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Multiple regression analysis of risk factors related to radiation pneumonitis
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作者 Ling-Ling Shi Jiang-Hua Yang Hong-Fa Yao 《World Journal of Clinical Cases》 SCIE 2023年第5期1040-1048,共9页
BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects patients’quality of life.AIM To carry out multiple regression an... BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects patients’quality of life.AIM To carry out multiple regression analysis on the influencing factors of radiation pneumonitis.METHODS Records of 234 patients receiving chest radiotherapy in Huzhou Central Hospital(Huzhou,Zhejiang Province,China)from January 2018 to February 2021,and the patients were divided into either a study group or a control group based on the presence of radiation pneumonitis or not.Among them,93 patients with radiation pneumonitis were included in the study group and 141 without radiation pneumonitis were included in the control group.General characteristics,and radiation and imaging examination data of the two groups were collected and compared.Due to the statistical significance observed,multiple regression analysis was performed on age,tumor type,chemotherapy history,forced vital capacity(FVC),forced expiratory volume in the first second(FEV1),carbon monoxide diffusion volume(DLCO),FEV1/FVC ratio,planned target area(PTV),mean lung dose(MLD),total number of radiation fields,percentage of lung tissue in total lung volume(vdose),probability of normal tissue complications(NTCP),and other factors.RESULTS The proportions of patients aged≥60 years and those with the diagnosis of lung cancer and a history of chemotherapy in the study group were higher than those in the control group(P<0.05);FEV1,DLCO,and FEV1/FVC ratio in the study group were lower than those in the control group(P<0.05),while PTV,MLD,total field number,vdose,and NTCP were higher than in the control group(P<0.05).Logistic regression analysis showed that age,lung cancer diagnosis,chemotherapy history,FEV1,FEV1/FVC ratio,PTV,MLD,total number of radiation fields,vdose,and NTCP were risk factors for radiation pneumonitis.CONCLUSION We have identified patient age,type of lung cancer,history of chemotherapy,lung function,and radiotherapy parameters as risk factors for radiation pneumonitis.Comprehensive evaluation and examination should be carried out before radiotherapy to effectively prevent radiation pneumonitis. 展开更多
关键词 Radiation pneumonitis Influencing factors RADIOTHERAPY Multiple regression analysis
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Quality of life of hospitalized patients after lung cancer operation and analysis of influencing factors
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作者 HU Yi‑fan HUANG Xiu‑ming +8 位作者 XIAO Sha ZHOU Jing WANG Shuo‑min WU Qi‑sheng ZHOU Bing‑xian FAN Shi‑heng FAN Ya‑yan CHEN Xian‑shan ZHANG Jing 《Journal of Hainan Medical University》 CAS 2023年第12期41-46,共6页
Objective:To explore the current status and influencing factors of quality of life in patients with lung cancer after surgery in a tertiary hospital in Hainan province.Methods:To investigate the influencing factors of... Objective:To explore the current status and influencing factors of quality of life in patients with lung cancer after surgery in a tertiary hospital in Hainan province.Methods:To investigate the influencing factors of quality of life of lung cancer patients after surgery in a tertiary hospital in Hainan province by cross‑sectional survey method.Results:The scores of insomnia,appetite loss,constipation and pain in 186 lung cancer patients after surgery in a tertiary hospital in Hainan Province were significantly higher than the reference value.Multiple linear regression analysis showed that older patients(>60 years)had lower scores in physical function domain(β=-0.193),and female patients had more appetite loss symptoms(β=0.245).Compared with other minority ethnic groups,Han ethnic group had lower scores in role function domain(β=0.179),more severe fatigue symptoms(β=-0.162),and higher general health level(β=0.166).Patients with employee medical insurance had lower scores of emotional function(β=0.194),cognitive function(β=0.281),the lowest score in social function(β=0.188),and severe pain in other parts(β=-0.227).Smokers had less cough symptoms(β=0.175)and more arm and shoulder pain symptoms(β=-0.21)than non‑smokers.Patients with secondhand smoke exposure had lower cognitive function scores(β=-0.158)and more obvious symptoms of oral ulcer(β=0.185).Patients who drank alcohol frequently(drinking frequency>1 time/day)had more severe cough symptoms(β=0.27).Patients with small number of children(0‑1)had milder cough symptoms(β=0.178).Patients who did not understand the disease had obvious symptoms of arm and shoulder pain(β=0.151).Patients with early pathological stage(stageⅠ‑Ⅱ)had more severe shortness of breath(β=-0.159)and pain(β=-0.181).The symptoms of appetite loss were more obvious in patients living in cities(β=0.192).The symptoms of peripheral neuropathy were more obvious(β=0.174).Patients who often consumed pickulated food had severe pain symptoms(β=-0.219),and pain in other parts was obvious(β=-0.149).Male patients had obvious alopecia symptoms(β=-0.306).Conclusion:Age,ethnicity,residence,type of medical insurance,number of children,pathological stage of lung cancer,smoking,second‑hand smoke exposure,alcohol consumption,and frequent consumption of pickled food were related to the quality of life of lung cancer patients in hospital after surgery.Medical staff and family members should pay attention to the emotional communication of patients during the treatment of lung cancer patients in hospital after surgery.Patients should avoid exposure to smoking,alcohol and second‑hand smoke,and reduce consumption of pickled food. 展开更多
关键词 Lung cancer Patients in hospital after lung cancer SURGERY Quality of life The influencing factors Regression analysis
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Cycle Time Analysis of Open Pit Mining Dump Trucks
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作者 Baatarchuluun Enkhchuluun Bat-Ochir Batgerel Cao Ping 《International Journal of Geosciences》 2023年第8期689-709,共21页
This study demonstrates a practical cycle time analysis of dump truck haulage system of “Ukhaa Khudag” open-pit coal mine located in Umnugobi Province, Mongolia. It examines the possibility of minimizing the cycle t... This study demonstrates a practical cycle time analysis of dump truck haulage system of “Ukhaa Khudag” open-pit coal mine located in Umnugobi Province, Mongolia. It examines the possibility of minimizing the cycle time of the haulage system as well as factors impacting the speed of the dump truck. The current study divides the open pit mine road for the dump trucks into five sections which are bench road, ramp, surface road, dump road uphill, and dump road. Meanwhile, it investigates the influence of the length, the grade, and the rolling resistance of the road section on the cycle time. The data is analyzed using mathematical regression methods via Microsoft Excel program. For each of the five road sections, we compare the statistical calculations of three regression models: linear, quadratic and exponential;thus, a total of thirty regression models are obtained in this research. Accordingly, the cycle time for each road section is predicted by the most accountable model. The loaded and empty direction of the movement is measured and calculated for each road section, and it appears that the difference between the calculated mean value and the actual cycle time of the models is 0.82 seconds with a relative error of 2.51 percent. 展开更多
关键词 Dump Truck Cycle Time Mine Haul Road Regression analysis
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Unveiling the Predictive Capabilities of Machine Learning in Air Quality Data Analysis: A Comparative Evaluation of Different Regression Models
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作者 Mosammat Mustari Khanaum Md Saidul Borhan +2 位作者 Farzana Ferdoush Mohammed Ali Nause Russel Mustafa Murshed 《Open Journal of Air Pollution》 2023年第4期142-159,共18页
Air quality is a critical concern for public health and environmental regulation. The Air Quality Index (AQI), a widely adopted index by the US Environmental Protection Agency (EPA), serves as a crucial metric for rep... Air quality is a critical concern for public health and environmental regulation. The Air Quality Index (AQI), a widely adopted index by the US Environmental Protection Agency (EPA), serves as a crucial metric for reporting site-specific air pollution levels. Accurately predicting air quality, as measured by the AQI, is essential for effective air pollution management. In this study, we aim to identify the most reliable regression model among linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), logistic regression, and K-nearest neighbors (KNN). We conducted four different regression analyses using a machine learning approach to determine the model with the best performance. By employing the confusion matrix and error percentages, we selected the best-performing model, which yielded prediction error rates of 22%, 23%, 20%, and 27%, respectively, for LDA, QDA, logistic regression, and KNN models. The logistic regression model outperformed the other three statistical models in predicting AQI. Understanding these models' performance can help address an existing gap in air quality research and contribute to the integration of regression techniques in AQI studies, ultimately benefiting stakeholders like environmental regulators, healthcare professionals, urban planners, and researchers. 展开更多
关键词 Regression analysis Air Quality Index Linear Discriminant analysis Quadratic Discriminant analysis Logistic Regression K-Nearest Neighbors Machine Learning Big Data analysis
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The Establishment of Mathematical Models for the Composition Analysis and Identification of Ancient Glass Products
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作者 Jenny Zhang Ding Li +1 位作者 Yu Xie Junfeng Xiang 《Open Journal of Applied Sciences》 2023年第11期2149-2171,共23页
Glass is the precious material evidence of the trade of the early Silk Road. The ancient glass was easily affected by the environmental impact and weathering, and the change of composition ratios affected the correct ... Glass is the precious material evidence of the trade of the early Silk Road. The ancient glass was easily affected by the environmental impact and weathering, and the change of composition ratios affected the correct judgment of its category. In this paper, mathematical models and methods such as Chi-square test, weighted average method, principal component analysis, cluster analysis, binary classification model and grey correlation analysis were used comprehensively to analyze the data of sample glass products combined with their categories. The results showed that the weathered high-potassium glass could be divided into 12, 9, 10 and 27, 7, 22 and so on. 展开更多
关键词 Principal Component analysis System Clustering Sensitivity analysis Binary Classification Model Logistic Regression analysis Grey Correlation analysis
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Rapid Prototype Development Approach for Genetic Programming
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作者 Pei He Lei Zhang 《Journal of Computer and Communications》 2024年第2期67-79,共13页
Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of ... Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of genetic operators, evolutionary controls and implementations of heuristic strategy, evaluations and other mechanisms. When designing genetic operators, it is necessary to consider the possible limitations of encoding methods of individuals. And when selecting evolutionary control strategies, it is also necessary to balance search efficiency and diversity based on representation characteristics as well as the problem itself. More importantly, all of these matters, among others, have to be implemented through tedious coding work. Therefore, GP development is both complex and time-consuming. To overcome some of these difficulties that hinder the enhancement of GP development efficiency, we explore the feasibility of mutual assistance among GP variants, and then propose a rapid GP prototyping development method based on πGrammatical Evolution (πGE). It is demonstrated through regression analysis experiments that not only is this method beneficial for the GP developers to get rid of some tedious implementations, but also enables them to concentrate on the essence of the referred problem, such as individual representation, decoding means and evaluation. Additionally, it provides new insights into the roles of individual delineations in phenotypes and semantic research of individuals. 展开更多
关键词 Genetic Programming Grammatical Evolution Gene Expression Programming Regression analysis Mathematical Modeling Rapid Prototype Development
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Participatory Forest Management and Gender Inclusiveness within the Community Forest Management Groups of Bhutan
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作者 Norbu Zangmo Takuya Hiroshima +1 位作者 Spencer Sibanda Jigme Dorji 《Journal of Geoscience and Environment Protection》 2024年第4期12-30,共19页
Community forest management groups (CFMGs) in Bhutan exhibit participatory forest management practices that recognize the importance of community’s collective participation in the management of natural forest resourc... Community forest management groups (CFMGs) in Bhutan exhibit participatory forest management practices that recognize the importance of community’s collective participation in the management of natural forest resources. This approach involves the community in the stewardship of designated forest areas and resources to ensure sustainable livelihoods and realization of forest conservation objectives. The increase of CFMGs in the country has been successful. However, research on the extent of gender-inclusive participation in CFMGs is either insufficient or missing vis-à-vis the allocation of decision-making power. Therefore, this study analyzes the factors influencing gender participation in CFMGs and their integration into decision-making processes. Primary data were collected from 12 study sites spanning 4 regions, complemented by secondary data from the Forest Department. Regression models were used to identify factors significantly influencing CFMG member participation in decision-making. The empirical results of this study reveal that gender is a significant factor influencing participation in CFMG decision-making. The study concludes that there is insufficient participation of women members in decision-making processes. Therefore, consideration of gender should be included in the development phase of the CFMG policy in addition to promoting awareness of inequity between gender and the promotion of leadership roles for women in CFMGs. 展开更多
关键词 DECISION-MAKING Face-to-Face Interview Regression analysis WOMEN
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Infinite Loop?What Is Behind the Ongoing Turmoil in the Banking Sector?
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作者 Kong Decong Huanyu Li 《Economics World》 2024年第2期77-82,共6页
The war in Ukraine is unfortunately not over,to add insult to injury,Silicon Valley Bank collapses and Credit Suisse acquired by UBS under the Swiss emergency legislation.The merger of Credit Suisse with UBS,Switzerl... The war in Ukraine is unfortunately not over,to add insult to injury,Silicon Valley Bank collapses and Credit Suisse acquired by UBS under the Swiss emergency legislation.The merger of Credit Suisse with UBS,Switzerland’s biggest bank,has also raised concerns about the proliferation of more institutions deemed“too big to fail”.Through the study of four financial crises in the past 100 years,this paper believes that behind this potential financial crisis is still the real estate bubble,but the significant problems in the United States are the most worrying.Post-financial crisis recessions are costlier and last longer than normal recessions.When credit booms are superimposed with asset price bubbles,financial crises are highly likely and economic recovery will be slower.In this paper,relative data and regression model are used to analyze the causes of the crisis;further this paper discusses the reasons behind the financial crisis and related conjectures and gives relevant development speculations. 展开更多
关键词 financial crisis real estate regression analysis
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Impacts of COVID-19 pandemic on urban park visitation:a global analysis 被引量:3
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作者 Dehui(Christina)Geng John Innes +1 位作者 Wanli Wu Guangyu Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期553-567,共15页
The COVID-19 pandemic has resulted in over 33 million confirmed cases and over 1 million deaths globally,as of 1 October 2020.During the lockdown and restrictions placed on public activities and gatherings,green space... The COVID-19 pandemic has resulted in over 33 million confirmed cases and over 1 million deaths globally,as of 1 October 2020.During the lockdown and restrictions placed on public activities and gatherings,green spaces have become one of the only sources of resilience amidst the coronavirus pandemic,in part because of their positive effects on psychological,physical and social cohesion and spiritual wellness.This study analyzes the impacts of COVID-19 and government response policies to the pandemic on park visitation at global,regional and national levels and assesses the importance of parks during this global pandemic.The data we collected primarily from Google’s Community Mobility Reports and the Oxford Coronavirus Government Response Tracker.The results for most countries included in the analysis show that park visitation has increased since February 16th,2020 compared to visitor numbers prior to the COVID-19 pandemic.Restrictions on social gathering,movement,and the closure of workplace and indoor recreational places,are correlated with more visits to parks.Stay-at-home restrictions and government stringency index are negatively associated with park visits at a global scale.Demand from residents for parks and outdoor green spaces has increased since the outbreak began,and highlights the important role and benefits provided by parks,especially urban and community parks,under the COVID-19 pandemic.We provide recommendations for park managers and other decision-makers in terms of park management and planning during health crises,as well as for park design and development.In particular,parks could be utilized during pandemics to increase the physical and mental health and social well-being of individuals. 展开更多
关键词 COVID-19 COVID-19 response policies Parks visitation Stepwise regression analysis Urban parks
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Theoretical analysis of natural frequency of externally prestressed concrete beam based on rigidity correction 被引量:3
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作者 Hui-xia Xiong1,2, Yao-ting Zhang11.School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan 430074, China 2.Department of Civil Engineering, Nanyang Institute of Technology, Nanyang 473004, China. 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第1期31-35,共5页
A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase w... A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula. 展开更多
关键词 externally prestressed concrete beam natural frequency rigidity correction regression analysis
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Sensitivity analysis of Biome-BGCMuSo for gross and net primary productivity of typical forests in China 被引量:2
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作者 Hongge Ren Li Zhang +2 位作者 Min Yan Xin Tian Xingbo Zheng 《Forest Ecosystems》 SCIE CSCD 2022年第1期111-123,共13页
Background:Process-based models are widely used to simulate forest productivity,but complex parameterization and calibration challenge the application and development of these models.Sensitivity analysis of numerous p... Background:Process-based models are widely used to simulate forest productivity,but complex parameterization and calibration challenge the application and development of these models.Sensitivity analysis of numerous parameters is an essential step in model calibration and carbon flux simulation.However,parameters are not dependent on each other,and the results of sensitivity analysis usually vary due to different forest types and regions.Hence,global and representative sensitivity analysis would provide reliable information for simple calibration.Methods:To determine the contributions of input parameters to gross primary productivity(GPP)and net primary productivity(NPP),regression analysis and extended Fourier amplitude sensitivity testing(EFAST)were conducted for Biome-BGCMuSo to calculate the sensitivity index of the parameters at four observation sites under climate gradient from ChinaFLUX.Results:Generally,GPP and NPP were highly sensitive to C:Nleaf(C:N of leaves),Wint(canopy water interception coefficient),k(canopy light extinction coefficient),FLNR(fraction of leaf N in Rubisco),MRpern(coefficient of linear relationship between tissue N and maintenance respiration),VPDf(vapor pressure deficit complete conductance reduction),and SLA1(canopy average specific leaf area in phenological phase 1)at all observation sites.Various sensitive parameters occurred at four observation sites within different climate zones.GPP and NPP were particularly sensitive to FLNR,SLA1 and Wint,and C:Nleaf in temperate,alpine and subtropical zones,respectively.Conclusions:The results indicated that sensitivity parameters of China's forest ecosystems change with climate gradient.We found that parameter calibration should be performed according to plant functional type(PFT),and more attention needs to be paid to the differences in climate and environment.These findings contribute to determining the target parameters in field experiments and model calibration. 展开更多
关键词 Sensitivity analysis Biome-BGCMuSo PRODUCTIVITY Regression analysis EFAST
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Logistics Regression Analysis between TCM Constitution Types of Patients with Hypertension,Insomnia and ABPM,PSQI 被引量:2
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作者 Xiaogang YU Qingsheng WANG +2 位作者 Erdan XIN Yujun LU Yingdong LI 《Medicinal Plant》 CAS 2022年第2期44-49,54,共7页
[Objectives]The research aimed to explore the distribution characteristics of TCM constitution types of patients with hypertension and insomnia,and study the clinical characteristics of patients with different constit... [Objectives]The research aimed to explore the distribution characteristics of TCM constitution types of patients with hypertension and insomnia,and study the clinical characteristics of patients with different constitutions,in order to provide new ideas for the treatment of patients with hypertension and insomnia.[Methods]Cross sectional observation method was used,and 420 patients with hypertension and insomnia were selected.Required information was collected,and the constitution type of traditional Chinese medicine was determined,and relevant data were recorded.SPSS and Logistic regression analysis method were used to explore the correlation between the distribution of TCM constitution types and gender,age,24 h-SBP,24 h-DBP,24 h-BPV,PSQI score,etc.[Results]Among 420 patients,the proportion of gentleness constitution was the most,and others in turn were Qi deficiency constitution>Yang deficiency constitution>phlegm dampness constitution>Qi stagnation constitution>Yin deficiency constitution>blood stasis constitution>damp heat constitution>special constitution.Among male patients,the proportion of gentleness constitution was the most.Among female patients,the proportion of Qi deficiency constitution was the most.In each constitution,the proportion of men and women was different,and the difference in gentleness constitution,Qi deficiency constitution and Yin deficiency constitution had statistical significance(P<0.05).The proportion of gentleness constitution for young and middle-aged patients was the most,while elderly patients with Qi deficiency constitution was the most.There was difference in the distribution of TCM constitution in different age groups,and the difference had statistical significance(P<0.05).Compared with the patients with gentleness constitution,the patients with Qi deficiency constitution,Yang deficiency constitution,Yin deficiency constitution,damp heat constitution,blood stasis constitution and Qi stagnation constitution had different differences in terms of age,24 h-SBP,24 h-DBP,24 h-BPV and PSQI score,and there was statistical significance(P<0.05).Except damp heat constitution,blood stasis constitution and special constitution,other constitutions had certain correlation with age,24 h-SBP,24 h-DBP,24 h-BPV and PSQI score.[Conclusions]TCM constitution types of patients with hypertension and insomnia were dominant by gentleness constitution,Qi deficiency constitution and Yang deficiency constitution.The distribution of TCM constitution in different gender and age groups was different,and different TCM constitution was related to ABPM and PSQI. 展开更多
关键词 Hypertension with insomnia Constitution of traditional Chinese medicine ABPM PSQI Logistics regression analysis
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Analysis of the incidence and influencing factors of hyponatremia before ^(131)I treatment of differentiated thyroid carcinoma 被引量:1
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作者 Jing-Jia Cao Can-Hua Yun +3 位作者 Juan Xiao Yong Liu Wei Wei Wei Zhang 《World Journal of Clinical Cases》 SCIE 2021年第36期11173-11182,共10页
BACKGROUND Hyponatremia is a common clinical electrolyte disorder.However,the association between hyponatremia and acute hypothyroidism is unclear.Acute hypothyroidism is usually seen in patients who undergo preparati... BACKGROUND Hyponatremia is a common clinical electrolyte disorder.However,the association between hyponatremia and acute hypothyroidism is unclear.Acute hypothyroidism is usually seen in patients who undergo preparation for radioactive iodine therapy.AIM To analyze the incidence and influencing factors of hyponatremia in a condition of iatrogenic acute hypothyroidism in patients with differentiated thyroid cancer(DTC)before ^(131)I treatment.METHODS The study group consisted of 903 DTC patients who received ^(131)I treatment.The clinical data before and after surgery,as well as on the day of ^(131)I treatment were analyzed.According to the blood sodium level before ^(131)I treatment,patients were divided into the non-hyponatremia group and hyponatremia group.Correlations between serum sodium levels before ^(131)I treatment and baseline data were analyzed.Univariate analysis and binary logistic regression were performed to identify the influencing factors of hyponatremia.RESULTS A total of 903 patients with DTC,including 283(31.3%)males and 620(68.7%)females,with an average age of 43.8±12.7 years,were included in this study.The serum sodium levels before surgery and ^(131)I treatment were 141.3±2.3 and 140.5±2.1 mmol/L,respectively(P=0.001).However,the serum sodium levels in males and females before ^(131)I treatment were lower than those before surgery.Patients aged more than 60 years and less than 60 years also showed decreased serum sodium levels before ^(131)I treatment.In addition,the estimated glomerular filtration rate(eGFR)in males and females decreased before ^(131)I treatment compared with those before surgery(P=0.001).Moreover,eGFR in patients over 60 years and under 60 years decreased before ^(131)I treatment,when compared with that before surgery.There were no significant differences in serum potassium,calcium,albumin,hemoglobin,and blood glucose in patients before surgery and ^(131)I treatment(P>0.05).Among the 903 patients,23(2.5%)were diagnosed with hyponatremia before ^(131)I treatment,including 21 cases(91.3%)of mild hyponatremia and 2 cases(8.7%)of moderate hyponatremia.Clinical data showed that patients with mild hyponatremia had no specific clinical manifestations,while moderate hyponatremia cases were mainly characterized by fatigue and dizziness,which were similar to neurological symptoms caused by hypothyroidism and were difficult to distinguish.Correlation analysis showed a correlation between serum sodium before ^(131)I treatment and the preoperative level(r=0.395,P=0.001).There was no significant correlation between blood sodium and thyroid-stimulating hormone(TSH)levels and urine iodine before ^(131)I treatment(r=0.045,P=0.174;r=0.013,P=0.697).Univariate analysis showed that there were significant differences in age,sex,history of diuretic use,distant metastasis,preoperative blood sodium,blood urea nitrogen(BUN),eGFR,TSH and urinary iodine between the two groups(all P<0.05).Logistic regression analysis showed that factors such as history of diuretic use,distant metastases,preoperative sodium and BUN were all influencing factors of hyponatremia.The Hosmer and Lemeshow test(c2=2.841,P=0.944)suggested a high fit of the model.Omnibus tests of model coefficients indicated the overall significance of the model in this fitted model(P<0.05).Preoperative serum sodium was a significant factor associated with pre-^(131)I therapy hyponatremia(OR=0.763;95%CI:0.627-0.928;P=0.007).CONCLUSION The incidence of hyponatremia induced by ^(131)I treatment preparation was not high.Preparation for radioactive iodine therapy was not a risk factor for the development of hyponatremia in thyroid cancer patients. 展开更多
关键词 Differentiated thyroid cancer HYPONATREMIA INCIDENCE Low iodine diet Logistic regression analysis
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Analysis on Precipitation Variation in Anyang and Nanyang in Recent 57 Years 被引量:1
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作者 LIU Yan 《Meteorological and Environmental Research》 CAS 2011年第3期10-13,共4页
[Objective] The aim was to analyze precipitation variation in Anyang and Nanyang in recent 57 years. [Method] Based on the data of annual precipitation in Anyang and Nanyang from 1953 to 2009, the changes of precipita... [Objective] The aim was to analyze precipitation variation in Anyang and Nanyang in recent 57 years. [Method] Based on the data of annual precipitation in Anyang and Nanyang from 1953 to 2009, the changes of precipitation in Anyang and Nanyang were compared by means of mathematical statistics, regression analysis and wavelet analysis. [Result] In recent 57 years, annual precipitation in Anyang and Nanyang showed decrease trend, especially Anyang with obvious decrease trend; from seasonal variation, average precipitation in spring and winter went up in Anyang and went down in Nanyang, while average precipitation in summer and autumn reduced in two cities; from periodic variation, when the time scale of precipitation in Anyang was 12-15 years, there was a catastrophe point in 1970, and Nanyang had two catastrophe points in 1965 and 1997 when the time scale of precipitation was 15 years and 4 catastrophe points in 1968, 1978, 1987 and 1999 when time scale was 7-10 years. [Conclusion] The study could provide theoretical foundation for the forecast of local climate changes. 展开更多
关键词 Precipitation changes Regression analysis Wavelet analysis ANYANG Nanyang China
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Regional Hypsometric Analysis of the Jordan Rift Drainage Basins (Jordan) Using Geographic Information System 被引量:2
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作者 Yahya Farhan Rami Mousa +1 位作者 Arij Dagarah Durgham Shtaya 《Open Journal of Geology》 2016年第10期1312-1343,共32页
This research is intended to assess the regional pattern of hypsometric curves (HCs) and hypsometric integrals (HIs) for the watersheds draining into the Jordan Rift (River Jordan, the Dead Sea, and Wadi Araba watersh... This research is intended to assess the regional pattern of hypsometric curves (HCs) and hypsometric integrals (HIs) for the watersheds draining into the Jordan Rift (River Jordan, the Dead Sea, and Wadi Araba watersheds). Hypsometric analysis was performed on 22 drainage basins using ASTER DEM (30 m resolution) and GIS. The area-elevation ratio method was utilized to extract the hypsometric integral values within a GIS environment. A prominent variation exists in the HC shapes and HI values. The highest hypsometric values are found for the Dead Sea ( = 0.87) and River Jordan ( = 0.77) watersheds. Whereas the lowest values ( = 0.51) characterized Wadi Araba catchments, except Wadi Nukhaileh (lower Wadi Araba) which yields an HI value of 0.26. Seventeen HCs pertained to the River Jordan and the Dead Sea watersheds evince remarkably upward convex shapes indicating that such drainage basins are less eroded, and at the youth-stage of the geomorphic cycle of erosion. Catchments draining to Wadi Araba are of intermediate HI values (0.41 - 0.58) which are associated with a balance, or dynamic equilibrium between erosion and tectonic processes. Accordingly, they correspond to a late mature stage of geomorphic development. Additionally, Wadi Nukhaileh yields the lowest HI value (0.26) and is associated with highly eroded terrain of late mature geomorphic evolution, approaching an old stage therefore, with distorted concave upward curves. High HI values indicate that these watersheds have been subjected to tectonic uplift, down faulting of the Rift and intense rejuvenation. Differences in HI values can be attributed to disparity in tectonic uplift rate, base level heights, and mean heights of the River Jordan watersheds, the Dead Sea and Wadi Araba watersheds, and variation in lithology, which caused noticeable differences in rejuvenation processes, and channel incision. Regression analysis reveals that R<sup>2</sup> values which represent the degree of control of driving parameters on HI, are positive and generally low (ranging from 0.026 to 0.224) except for the height of base level (m) parameter which contributes 0.42 (significant at 0.1% level). Such results mean that the height of base level has a significant at 0.1% level. It is obvious that the most crucial driving morphometric factor influencing HI values of the Jordan Rift drainage basins, is the height of base level (m). 展开更多
关键词 Hypsometric analysis Tectonic Activity GIS ASTER DEM Regression analysis Jordan Rift
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Econometric Analysis of Factors Affecting Special Purpose Forests in China 被引量:1
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作者 Wang Lanhui Cai Fei 《Forestry Studies in China》 CAS 2003年第4期37-40,共4页
The forest estate is one of our most important natural resources. It is also the material foundation for sustainable forestry development in China. It is a timely topic of concern within the forestry community and tou... The forest estate is one of our most important natural resources. It is also the material foundation for sustainable forestry development in China. It is a timely topic of concern within the forestry community and touches the entire society. From a social economic point of view, the sustainable development has been promoted by the efficient use of the forest resources in a continuing improvement of the environment. The objective of the present analysis is to measure the effect of various factors, such as population, economic development and related policies on the use of the forest resources. The 29 provinces of China's Mainland are classified in three regions, based largely on their level of economic development. For each region, the factors which affect the area of special purpose forests (SPF) are analyzed. Some recommendations are made for further improvement. 展开更多
关键词 forest resource special purpose forest(SPF) ECONOMETRICS regression analysis
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Analysis of a Conceptual Model and Assessment of the e-Procurement System in Bangladesh 被引量:1
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作者 Md. Abdur Rashid Mohammad Shorif Uddin 《Journal of Computer and Communications》 2021年第11期64-76,共13页
The public procurement system in Bangladesh has been running by traditional manual process under the flagship of Public Procurement Act (PPA 2006) and Public Procurement Rules (PPR 2008). Public procurement agencies h... The public procurement system in Bangladesh has been running by traditional manual process under the flagship of Public Procurement Act (PPA 2006) and Public Procurement Rules (PPR 2008). Public procurement agencies have been facing challenges in this manual tendering system. To overcome this problem and to bring reality to the “Digital Bangladesh” slogan, the Government of Bangladesh introduced the e-Procurement system under the e-GP (Electronic Government Procurement) guideline 2011. After the inception of e-procurement, there is no e-procurement assessment model to improve the e-GP system. The purpose of this research is to develop a conceptual framework and to design an e-procurement assessment model. With this view, we have considered one of the biggest entity Roads and Highways Department (RHD) of the Government of Bangladesh, for field study. Mixed methods along with FGD (Focus Group Discussion), KII (Key Informant Interview), and survey questionnaires are used to collect data from RHD, and then Statistical Package for Social Science (SPSS) software is used for regression analysis and hypothesis testing to develop the e-Procurement assessment model. The novel contribution of the study lies in the test of the hypothesis that focuses on developing the conceptual model of the e-procurement assessment system in Bangladesh. Findings of the study are essential for all Procurement Entity (PE) and suppliers <i>i.e. </i> contractors of RHD who are engaged in the construction of the infrastructure project development project. 展开更多
关键词 e-GP Guideline 2011 Conceptual Framework e-Procurement Assessment Model Hypothesis Test Regression analysis
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Research on the Effect of Artificial Intelligence Real Estate Forecasting Using Multiple Regression Analysis and Artificial Neural Network: A Case Study of Ghana 被引量:1
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作者 Madami Michael Ishaku Hill Isaac Lewu 《Journal of Computer and Communications》 2021年第10期1-14,共14页
To transition from conventional to intelligent real estate, the real estate industry must enhance its embrace of disruptive technology. Even though the real estate auction market has grown in importance in the financi... To transition from conventional to intelligent real estate, the real estate industry must enhance its embrace of disruptive technology. Even though the real estate auction market has grown in importance in the financial, economic, and investment sectors, few artificial intelligence-based research has tried to predict the auction values of real estate in the past. According to the objectives of this research, artificial intelligence and statistical methods will be used to create forecasting models for real estate auction prices. A multiple regression model and an artificial neural network are used in conjunction with one another to build the forecasting models. For the empirical study, the study utilizes data from Ghana apartment auctions from 2016 to 2020 to anticipate auction prices and evaluate the forecasting accuracy of the various models available at the time. Compared to the conventional Multiple Regression Analysis, using artificial intelligence systems for real estate appraisal is becoming a more viable option (MRA). The Artificial Neural network model exhibits the most outstanding performance, and efficient zonal segmentation based on the auction evaluation price enhances the model’s prediction accuracy even more. There is a statistically significant difference between the two models when it comes to forecasting the values of real estate auctions. 展开更多
关键词 Real Estate Forecasting Artificial Intelligence Artificial Neural Networks Multiple Regression analysis
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An empirical analysis on community residents' perception and major influencing factors of rural tourism development 被引量:1
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作者 WEI Lang-jie YAN Zhao-nan +1 位作者 LI Kai-li GU Ya-qing 《Ecological Economy》 2021年第3期176-185,共10页
With the rapid development of rural tourism in China,community residents,as important stakeholders in the development of rural tourism,their perceptions and attitudes directly affect the sustainable and healthy develo... With the rapid development of rural tourism in China,community residents,as important stakeholders in the development of rural tourism,their perceptions and attitudes directly affect the sustainable and healthy development of local rural tourism.Taking the community residents of Xiaogucheng Village in Hangzhou as the research object,using the methods of field interviews and questionnaires,a multiple regression model was established to conduct an empirical analysis on the perception and main factors affecting the development of rural tourism of community residents.The results show that the development of rural tourism in villages with better economic development is not as popular as expected;Where community residents have made ideological progress and are willing to participate in tourism development,the development effect of rural tourism is remarkable;In addition,community residents also hope that their personal abilities can be combined with rural tourism for common development;The destruction of community environment has a slight impact on the development of rural tourism,which shows that the attention is not enough.Finally,based on the analysis conclusion,it provides new ideas and inspiration for the sustainable development of rural tourism:improving the community residents’participation in rural tourism system,establishing the guidance mechanism of community residents’tourism vocational education,and consolidating the achievements of community ecological environment management. 展开更多
关键词 rural tourism community residents’perception multiple regression analysis model
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