correlation

摘要： Drop weight impact tester was used to accurately measure the bending impact resistance of various parts of Phyllostachys edulis,commonly known as moso bamboo,with a growth cycle of 3–8 years.Cellulose crystallinity in the bottom(B),middle(M)and top(T)of bamboo at different ages was calculated using peak height analysis in X-ray diffraction.Heatmap of Spearman correlation analysis was used to represent the correlation between chemical composition and impact mechanics.The breaking load(BL),fracture energy(FE)and impact deflection(ID)of 3–8-year-old bamboo were found to be in the range of~670–2120 N,~5.17–15.55 J,and~3.60–~17.76 mm,respectively.As the growth period of bamboo rises,the cellulose crystallinity at the B and T decreases first and then increases,while that for the M increases first and then remains stable.Similarly,the bending impact performance of bamboo was found to become stable with its growth and age.The flexural impact and toughness of the 4-year-old bamboo base material were better than other specimens.The enhancement in the bending impact properties of bamboo at different growth periods was influenced by the lignin content,while the value of FE was mainly positively correlated with ash,cold and hot water extracts and benzyl alcohol content.However the content of holocellulose and pentosan,air-dry density and,base density negatively influenced the FE.With the change in the height of the bamboo,the correlation between its impact mechanical properties and chemical composition gradually decreased.This study provides data support and theoretical basis for the age-appropriate thinning and application of moso bamboo.

摘要： Based on the monitoring data of chemical oxygen demand(COD),permanganate index(I Mn)and five-day biochemical oxygen demand(BOD 5)of surface water in Tongling section of Yangtze River,the linear relationship among the three indexes in the annual data analysis and the internal reasons,as well as the linear relationship and changes among the three indexes in different seasons were analyzed.The results reveal that in terms of the whole year,COD,I Mn and BOD 5 had a significant correlation and good linear relationship.The fitting slopes of the three indexes were 3.89 of COD/I Mn,4.39 of COD/BOD 5 and 1.16 of I Mn/BOD 5,respectively,which corresponded to the proportional relationship among the three indexes.From the perspective of seasonal changes,there was a very significant correlation between the three indexes in spring and summer.In autumn and winter,only COD and I Mn had a good correlation,but they had a poor correlation with BOD 5.

摘要： BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is characterized by hypertriglyceridemia,increased low-density lipoprotein cholesterol levels,and reduced highdensity lipoprotein cholesterol(HDL-C)particles.Previous studies have shown that the total cholesterol to high-density lipoprotein cholesterol ratio(TC/HDL-C)was superior to other lipid metabolism biomarkers for predicting NAFLD risk and could be a new indicator of NAFLD.However,the association between TC/HDL-C and NAFLD in patients with hepatitis B virus(HBV)has not yet been determined.AIM To investigate the association between TC/HDL-C and NAFLD in a population with chronic hepatitis B(CHB).METHODS In this study,183 HBV-infected patients were enrolled.All participants underwent blood chemistry examinations and abdominal ultrasound.Univariate and multivariate logistic regression models,curve fitting analysis,and threshold calculation were used to assess the relationship between TC/HDL-C and NAFLD.RESULTS The overall prevalence of NAFLD was 17.49%(n=32)in the 183 CHB participants.The TC/HDL-C of non-NAFLD and NAFLD patients were 3.83±0.75 and 4.44±0.77,respectively(P<0.01).Logistic regression analysis showed that TC/HDL-C was not associated with NAFLD after adjusting for other pertinent clinical variables.However,at an optimal cutoff point of 4.9,a non-linear correlation between TC/HDL-C and NAFLD was detected.The effect size of the left and right sides of the inflection point were 5.4(95%confidence interval:2.3-12.6,P<0.01)and 0.5(95%confidence interval:0.1-2.2,P=0.39),respectively.On the left side of the inflection point,TC/HDL-C was positively associated with NAFLD.However,no significant association was observed on the right side of the inflection point.CONCLUSION This study demonstrated a non-linear correlation between TC/HDL-C and NAFLD in a population with CHB.TC/HDL-C was positively associated with NAFLD when TC/HDL-C was less than 4.9 but not when TC/HDL-C was more than 4.9.

摘要： Serum biochemical and meat fatty acid profile of different chickens were studied. A total of 144 mixed sex matured chickens of Cosmopolitan (C), Improved Horro (H), Cosmopolitan♂*Improved Horro♀(CH), Improved Horro♂*Cosmopolitan♀ (HC), Indigenous (L) and Koekkoek (KK) were used to determine serum biochemical, of which 36 chickens were also used for fatty acid profile study. Completely randomized design in 6 × 2 factorial arrangements was set up. Serum biochemical and fatty acid profiles were determined by Roche/Hitachi cobas c 501 and gas liquid chromatography (GC) procedures, respectively. There were significant differences (P ≤ 0.001) in Total cholesterol (TC), Triglyceride (TG), Low-density lipoprotein (LDL) and High-density lipoprotein (HDL) among genotypes and between sexes. HDL was inversely related with TC, TG and LDL. Male had significantly higher (P ≤ 0.001) TC, TG, LDL but lower HDL than female. SFA, (Myristic, Pentadecanoic and Palmitic acids) had significantly (P α-linolenic acid significantly (P ≤ 0.01) varied between sexes. The serum biochemical differed across genotypes and between sexes. The difference in the number of carbons, double bond and position of the double bond could affect fatty acid profile among genotypes and between sexes. Chicken products with higher level TC, TG, LDL and SFA might affect human health problems. It could also be interesting topic for future studies.

摘要： Wind power,solar power,and electrical load forecasting are essential works to ensure the safe and stable operation of the electric power system.With the increasing permeability of new energy and the rising demand response load,the uncertainty on the production and load sides are both increased,bringing new challenges to the forecasting work and putting forward higher requirements to the forecasting accuracy.Most review/survey papers focus on one specific forecasting object(wind,solar,or load),a few involve the above two or three objects,but the forecasting objects are surveyed separately.Some papers predict at least two kinds of objects simultaneously to cope with the increasing uncertainty at both production and load sides.However,there is no corresponding review at present.Hence,our study provides a comprehensive review of wind,solar,and electrical load forecasting methods.Furthermore,the survey of Numerical Weather Prediction wind speed/irradiance correction methods is also included in this manuscript.Challenges and future research directions are discussed at last.

摘要： At present,as of June 15,2019,the Ministry of Education announced a total of 2,956 institutions of higher learning in China,including 2,688 regular institutions of higher learning(including 266 independent colleges)and 268 adult institutions of higher learning.At present,the development of colleges and universities is also facing serious problems.With the development and progress of the times,many colleges and universities are getting better and better,which is closely related to the teachers’strength and teachers’job satisfaction.It is very important to improve the job satisfaction of university staff.The introduction of teachers is crucial,and many schools are weak in teaching staff,which hinders the long-term development of schools.The turnover of teachers in colleges and universities is closely related to job satisfaction.At present,the overall turnover of teachers in colleges and universities is too frequent.The rapid development of China’s colleges and universities is still expanding the scale of development,which requires more teachers.In the ensuing enterprise competition,university positions are not dominant,mainly in the current life,salary is very important,family expenses,parents,and children’s expenses are getting higher and higher,but the salary of university teachers cannot keep up with the development of the times.At present,one of the problems in colleges and universities is that salary promotion is not friendly to teachers with old qualifications,high academic qualifications,and high professional titles.Therefore,to improve the job satisfaction of college teachers is the only way for the long-term development of colleges and universities.This study investigated the relationship between job satisfaction and employee performance among 341 teachers from N University in Nanning,Guangxi province,China.The independent variable is six factors of job satisfaction,including working environment,salary and promotion,job security,relationship with colleagues,relationship with supervisor,and fairness level.The dependent variable is three factors of employee performance,including enthusiasm,availability,and job engagement.Finally,through data analysis,it was concluded that there was a positive correlation between teachers’job satisfaction and staff performance in N University.

摘要： BACKGROUND Recent epidemiological studies have shown that general eye measurement parameters and corneal biomechanical properties can predict the speed of myopic progression in children.AIM To investigate the correlation between the onset and progression of myopia and corneal biomechanical parameters in children.METHODS The study included 102 cases in the emmetropia group,207 cases in the myopic group,and 109 cases in the hyperopic group.The correlation between the change in corneal biomechanical indexes and the change in general ocular measurement parameters was analyzed.A one-way ANOVA test compared general ocular measurement and corneal biomechanical parameters.Pearson’s correlation coefficient was analyzed to correlate corneal biomechanical and general ocular measurement parameters.RESULTS The general ophthalmometric parameters:Spherical equivalent(SE),intraocular pressure(IOP),and axial length(AL),differed significantly among subjects in myopia,emmetropia,and hyperopic groups.Children’s SE positively correlated with corneal biomechanical parameters:Second velocity of applanation(A2V),peak distance(PD),and deformation amplitude(DA)(P<0.05),and second applanation length(A2L)(P<0.05).But it was negatively correlated with PD,DA and integral radius(IR)(P<0.05).Also,IOP was negatively correlated with A2L and IR(P<0.05).AL positively correlated with A2V and negatively correlated with second applanation time(A2T),highest concavity,and PD.Central corneal thickness positively correlated with first applanation length,first applanation time,first applanation deformation amplitude,A2V,A2L,A2T,second applanation deformation amplitude,central curvature radius at highest concavity(HCR),PD,DA,IR,ambrosia relational thickness-horizontal,first applanation stiffness parameter,corvis biomechanical index,topographic and biomechanics index and the first velocity of applanation.The general ocular Km in children positively correlated with corneal biomechanical parameters DA and IR and negatively correlated with A2L,HCR,and PD.There was a positive correlation between the general ocular measurement parametersΔSE and corneal biomechanical parametersΔA2V andΔA2L,and a negative correlation withΔIR.The increase in general ocular measurement parameterΔKm positively correlated with changes in corneal biomechanical parameters,ΔDA andΔIR,and negatively correlated withΔHCR andΔPD.CONCLUSION Myopia development in children was associated with multiple corneal biomechanical parameters.

摘要： Ionomic profiles are primarily influenced by genetic and environmental factors.Identifying ionomic responses to varietal effects is necessary to understand the ionomic variations among species or subspecies and to potentially understand genetic effects on ionomic profiles.We cultivated 120 rice(Oryza sativa)varieties to seedling stage in identical hydroponic conditions and determined the concentrations of 26 elements(including 3 anions)in the shoots and roots of rice.Although the subspecies effects were limited by the genus Oryza pre-framework and its elemental chemical properties,we found significant differences in ionomic variations in most elements among the aus,indica and japonica subspecies.Principal component analysis of the correlations indicated that variations in the root-to-shoot ionomic transport mechanisms were the main causes of ionomic differences among the subspecies.Furthermore,the correlations were primarily associated with the screening of varieties for elemental covariation effects that can facilitate breeding biofortified rice varieties with safe concentrations of otherwise toxic elements.The japonica subspecies exhibited the strongest elemental correlations and elemental covariation effects,therefore,they showed greater advantages for biofortification than the indica and aus subspecies,whereas indica and aus subspecies were likely safer in metal(loid)polluted soils.We also found that geographical and historical distribution significantly defined the ionomic profiles.Overall,the results of this study provided a reference for further association studies to improve the nutritional status and minimize toxicity risks in rice production.

摘要： The relationship between some meteorological parameters and variation of total column ozone (TCO) concentration in Nigeria is studied from 1998-2012. The results using a descriptive analysis revealed a seasonal ozone variation having the same trend in all the stations during the period of study. High variability of TCO occurred between December and March coinciding with the period of dry season and low variability of TCO was observed in August coinciding with the period of rainy season. The observed trends in all the stations show that the TCO variation in Nigeria is mostly caused by natural occurrences. Calabar and Port Harcourt stations showed a high percent of TCO variability, while Kano and Maiduguri indicated a low percentage of TCO variability. Using Spearman correlation analysis, TCO concentration has a strong negative correlation with temperature in some stations with correlation coefficient (r) (-0.8392, -0.8531, -0.7832, -8881 and -0.7902) for Calabar, Port Harcourt, Makurdi, Lagos and Ilorin respectively. Kano and Maiduguri showed a weak positive correlation coefficient (r) 0.4965 and 0.3776 respectively. Positive correlation observed in Kano and Maiduguri could be as a result of high dehydration of water vapour in these stations due to seasonal harmattan and latitudinal effects. Probably, some of the substances that could deplete ozone such as HCl, aerosol are soluble in water thereby being washed off by rain during wet season leading to maximum TCO concentration during rainy season. Consequently, the observed phenomenon is through transportation of ozone content through the influence of Brewer-Dobson circulation. Again, during wet season, there is the mechanism of low pressure and lower tropopause height phenomenon, therefore, total ozone enhancement. Interestingly, variation in TCO is part of symbolic tools for tropospheric meteorology alteration and this invariably leads to climate change.

摘要： The capacity of wireless networks is fundamentally limited by interference. A few research has focused on the study of the simultaneous effect of interference and correlation, and less attention has been paid to the topic of canceling simultaneous effect of interference and correlation until recently. This paper considers a secure wireless multicasting scenario through multicellular networks over spatially correlated Nakagami-m fading channel in the presence of multiple eavesdroppers. Authors are interested to protect the desired signals from eavesdropping considering the impact of perfect channel estimation (PCE) with interference and correlation. The protection of eavesdropping is also made strong reducing the simultaneous impact of interference and correlation on the secrecy multicast capacity employing opportunistic relaying technique. In terms of the signal-to-interference plus noise ratio (SINR), fading parameter, correlation coefficient, the number of multicast users and eavesdroppers and the number of antennas at the multicast users and eavesdroppers, the closed-form analytical expressions are derived for the probability of non-zero secrecy multicast capacity and the secure outage probability for multicasting to understand the insight of the effects of aforementioned parameters. The results show that the simultaneous effects of correlation and interference at the multicast users degrade security in multicasting. Moreover, the security in multicasting degrades with the intensity of fading and the number of multicast users, eavesdroppers and antennas at the eavesdroppers. The effects of these parameters on the security in multicasting can be significantly reduced by using opportunistic relaying technique with PCE. Finally, the analytical results are verified via Monte-Carlo simulation to justify the validity of derived closed-form analytical expressions.

摘要： As Einstein said, the interest is the best teacher. Inhigher vocation education, interest is important not onlyfor students to learn well but also for teachers to teachwell, especially in practical teaching. In modernizationeducation principles, students play active roles in educa-tional activities. Teaching methodologies should takepeople as the foremost. Learning guidance by interest iswidely used in high vocation education, which promotesstudents’ subjective activity Practical teaching is a keyprocedure to stimulate students’ interest and help thembecome interested in their major. Therefore, it is neces-sary to do research on the relationship between learningguidance by interest and teaching effect. To demonstratethe influence of interest in teaching activities, this paperproposes an Interesting-Efficient (I-E) mode for learningguidance, and discusses the I-E mode in detailed theo-retically.This paper first analyzes the importance of interest in higher vocation education. Then, I-E mode oflearning guidance is proposed to describe the relationship between interestingness and the average teachingeffect and some theoretical analysis is conducted which provides scientific guidance to teachers when theydesign points of interest in one course.

摘要： As Einstein said, the interest is the best teacher. Inhigher vocation education, interest is important not onlyfor students to learn well but also for teachers to teachwell, especially in practical teaching. In modernizationeducation principles, students play active roles in educa-tional activities. Teaching methodologies should takepeople as the foremost. Learning guidance by interest iswidely used in high vocation education, which promotesstudents’ subjective activity Practical teaching is a keyprocedure to stimulate students’ interest and help thembecome interested in their major. Therefore, it is neces-sary to do research on the relationship between learningguidance by interest and teaching effect. To demonstratethe influence of interest in teaching activities, this paperproposes an Interesting-Efficient (I-E) mode for learningguidance, and discusses the I-E mode in detailed theo-retically.This paper first analyzes the importance of interest in higher vocation education. Then, I-E mode oflearning guidance is proposed to describe the relationship between interestingness and the average teachingeffect and some theoretical analysis is conducted which provides scientific guidance to teachers when theydesign points of interest in one course.

摘要： As Einstein said, the interest is the best teacher. Inhigher vocation education, interest is important not onlyfor students to learn well but also for teachers to teachwell, especially in practical teaching. In modernizationeducation principles, students play active roles in educa-tional activities. Teaching methodologies should takepeople as the foremost. Learning guidance by interest iswidely used in high vocation education, which promotesstudents’ subjective activity Practical teaching is a keyprocedure to stimulate students’ interest and help thembecome interested in their major. Therefore, it is neces-sary to do research on the relationship between learningguidance by interest and teaching effect. To demonstratethe influence of interest in teaching activities, this paperproposes an Interesting-Efficient (I-E) mode for learningguidance, and discusses the I-E mode in detailed theo-retically.This paper first analyzes the importance of interest in higher vocation education. Then, I-E mode oflearning guidance is proposed to describe the relationship between interestingness and the average teachingeffect and some theoretical analysis is conducted which provides scientific guidance to teachers when theydesign points of interest in one course.

摘要： As Einstein said, the interest is the best teacher. Inhigher vocation education, interest is important not onlyfor students to learn well but also for teachers to teachwell, especially in practical teaching. In modernizationeducation principles, students play active roles in educa-tional activities. Teaching methodologies should takepeople as the foremost. Learning guidance by interest iswidely used in high vocation education, which promotesstudents’ subjective activity Practical teaching is a keyprocedure to stimulate students’ interest and help thembecome interested in their major. Therefore, it is neces-sary to do research on the relationship between learningguidance by interest and teaching effect. To demonstratethe influence of interest in teaching activities, this paperproposes an Interesting-Efficient (I-E) mode for learningguidance, and discusses the I-E mode in detailed theo-retically.This paper first analyzes the importance of interest in higher vocation education. Then, I-E mode oflearning guidance is proposed to describe the relationship between interestingness and the average teachingeffect and some theoretical analysis is conducted which provides scientific guidance to teachers when theydesign points of interest in one course.

摘要： As Einstein said, the interest is the best teacher. Inhigher vocation education, interest is important not onlyfor students to learn well but also for teachers to teachwell, especially in practical teaching. In modernizationeducation principles, students play active roles in educa-tional activities. Teaching methodologies should takepeople as the foremost. Learning guidance by interest iswidely used in high vocation education, which promotesstudents’ subjective activity Practical teaching is a keyprocedure to stimulate students’ interest and help thembecome interested in their major. Therefore, it is neces-sary to do research on the relationship between learningguidance by interest and teaching effect. To demonstratethe influence of interest in teaching activities, this paperproposes an Interesting-Efficient (I-E) mode for learningguidance, and discusses the I-E mode in detailed theo-retically.This paper first analyzes the importance of interest in higher vocation education. Then, I-E mode oflearning guidance is proposed to describe the relationship between interestingness and the average teachingeffect and some theoretical analysis is conducted which provides scientific guidance to teachers when theydesign points of interest in one course.

摘要： Partial transmit sequence(PTS)is an effenciate technique to reduce peak-to-average ratio(PAPR)inorthogonal frequency division multiplexing(OFDM)system.But it has a high computational complexity.Toreduce the high complexity in PTS, a modified scheme,which is called Correction PTS(CPTS), is proposedbased on the correction among the candidate signals，which select only part of all the candidatesignals.Simulation shows that the modi PTS scheme can not only reduce computational complexity,but PAPRreduction performance is close to that of PTS.

摘要： Partial transmit sequence(PTS)is an effenciate technique to reduce peak-to-average ratio(PAPR)inorthogonal frequency division multiplexing(OFDM)system.But it has a high computational complexity.Toreduce the high complexity in PTS, a modified scheme,which is called Correction PTS(CPTS), is proposedbased on the correction among the candidate signals，which select only part of all the candidatesignals.Simulation shows that the modi PTS scheme can not only reduce computational complexity,but PAPRreduction performance is close to that of PTS.

摘要： Partial transmit sequence(PTS)is an effenciate technique to reduce peak-to-average ratio(PAPR)inorthogonal frequency division multiplexing(OFDM)system.But it has a high computational complexity.Toreduce the high complexity in PTS, a modified scheme,which is called Correction PTS(CPTS), is proposedbased on the correction among the candidate signals，which select only part of all the candidatesignals.Simulation shows that the modi PTS scheme can not only reduce computational complexity,but PAPRreduction performance is close to that of PTS.

摘要： Partial transmit sequence(PTS)is an effenciate technique to reduce peak-to-average ratio(PAPR)inorthogonal frequency division multiplexing(OFDM)system.But it has a high computational complexity.Toreduce the high complexity in PTS, a modified scheme,which is called Correction PTS(CPTS), is proposedbased on the correction among the candidate signals，which select only part of all the candidatesignals.Simulation shows that the modi PTS scheme can not only reduce computational complexity,but PAPRreduction performance is close to that of PTS.