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Circulating glycated albumin levels and gestational diabetes mellitus
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作者 Wei Xiong Zhao-Hui Zeng +2 位作者 Yuan Xu Hui Li Hui Lin 《World Journal of Diabetes》 SCIE 2024年第8期1802-1810,共9页
BACKGROUND Gestational diabetes mellitus(GDM)is characterized by glucose intolerance that is first diagnosed during pregnancy,making it the most common complication associated with this period.Early detection and targ... BACKGROUND Gestational diabetes mellitus(GDM)is characterized by glucose intolerance that is first diagnosed during pregnancy,making it the most common complication associated with this period.Early detection and targeted treatment of GDM can minimize foetal exposure to maternal hyperglycaemia and subsequently reduce the associated adverse pregnancy outcomes.Previous studies have inconsistently suggested that the level of glycated albumin(GA)might predict GDM.AIM To review and synthesize existing evidence to evaluate the relationship between GA levels and the development of GDM.METHODS We sought to compare GA levels between GDM and control groups in this metaanalysis by systematically searching the Web of Science,PubMed,Cochrane Library,and Embase databases for articles published up to June 2023.The analysis utilized the weighted mean difference(WMD)as the primary metric.The data were meticulously extracted,and the quality of the included studies was assessed.Additionally,we conducted a subgroup analysis based on study region and sample size.We assessed heterogeneity using I2 statistics and evaluated publication bias through funnel plots.Additionally,trim-and-fill analysis was employed to detect and address any potential publication bias.RESULTS The meta-analysis included a total of 11 studies involving 5477 participants,comprising 1900 patients with GDM and 3577 control individuals.The synthesized results revealed a notable correlation between elevated GA levels and increased susceptibility to GDM.The calculated WMD was 0.42,with a 95%confidence interval(95%CI)ranging from 0.11 to 0.74,yielding a P value less than 0.001.Concerning specific GA levels,the mean GA level in the GDM group was 12.6,while for the control group,it was lower,at 11.6.This discrepancy underscores the potential of GA as a biomarker for assessing GDM risk.Moreover,we explored the levels of glycated haemoglobin(HbA1c)in both cohorts.The WMD for HbA1c was 0.19,with a 95%CI ranging from 0.15 to 0.22 and a P value less than 0.001.This observation suggested that both GA and HbA1c levels were elevated in individuals in the GDM group compared to those in the control group.CONCLUSION Our meta-analysis revealed a substantial correlation between elevated GA levels and increased GDM risk.Furthermore,our findings revealed elevated levels of HbA1c in GDM patients,emphasizing the significance of monitoring both GA and HbA1c levels for early GDM detection and effective management. 展开更多
关键词 Glycated albumin Gestational diabetes mellitus Diabetes mellitus META-ANALYSIS Weighted mean difference
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New Results on One Modulo N-Difference Mean Graphs
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作者 Pon Jeyanthi Meganathan Selvi Damodaran Ramya 《Open Journal of Discrete Mathematics》 2023年第4期100-112,共13页
A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bije... A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bijection  from the edge set of G to given by and the function f is called a one modulo N-difference mean labeling of G. In this paper, we show that the graphs such as arbitrary union of paths, , ladder, slanting ladder, diamond snake, quadrilateral snake, alternately quadrilateral snake, , , , , friendship graph and admit one modulo N-difference mean labeling. 展开更多
关键词 Skolem Difference Mean Labeling One Modulo N-Graceful Labeling One Modulo N-Difference Mean Labeling and One Modulo N-Difference Mean Graph
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Color Image Quality Assessment Based on Structural Similarity 被引量:2
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作者 卢芳芳 赵群飞 杨根科 《Journal of Donghua University(English Edition)》 EI CAS 2010年第4期443-450,共8页
It is well-known that classical quality measures,such as Mean Squared Error(MSE),Weighted Mean Squared Error(WMSE)or Peak Signal-to-Noise Ratio(PSNR),are not always corresponding with visual observations.Structural si... It is well-known that classical quality measures,such as Mean Squared Error(MSE),Weighted Mean Squared Error(WMSE)or Peak Signal-to-Noise Ratio(PSNR),are not always corresponding with visual observations.Structural similarity based image quality assessment was proposed under the assumption that the Human Visual System(HVS)is highly adapted for extracting structural information from an image.While the demand on high color quality increases in the media industry,color loss will make the visual quality different.In this paper,we proposed an improved quality assessment(QA)method by adding color comparison into the structural similarity(SSIM)measurement system for evaluating color image quality.Then we divided the task of similarity measurement into four comparisons:luminance,contrast,structure,and color.Experimental results show that the predicted quality scores of the proposed method are more effective and consistent with visual quality than the classical methods using five different distortion types of color image sets. 展开更多
关键词 image quality assessment structural similarity difference mean opinion score color image
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About the Mean Difference of the Inverse Normal Distribution 被引量:1
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作者 Giovanni Girone Angela Maria D’Uggento 《Applied Mathematics》 2016年第14期1504-1509,共7页
The calculation of the mean difference for the inverse normal distribution can be obtained by a transformation of variable or a hard integration by parts. This paper shows a simpler formula of the mean difference of t... The calculation of the mean difference for the inverse normal distribution can be obtained by a transformation of variable or a hard integration by parts. This paper shows a simpler formula of the mean difference of the inverse normal distribution that highlights the role of the two parameters on the mean difference of the model. It makes it easier to study the relation of the mean difference with the other indexes of variability for the inverse normal distribution. 展开更多
关键词 Mean Difference Inverse Normal Distribution
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Generalizations of mixed weighted power mean inequality 被引量:1
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作者 马统一 张海娟 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期192-197,共6页
Tarnavas established mixed weighted power mean inequality in 1999. A separation of weighted power mean inequslity was derived in this paper. As its applications, some separations of other inequalities were given.
关键词 INEQUALITY power mean weighted power mean mixed weighted power mean difference function of mixed weightedpower mean separation
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Efficient Data Compression of ECG Signal Based on Modified Discrete Cosine Transform
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作者 Ashraf Mohamed Ali Hassan Mohammed S.Alzaidi +1 位作者 Sherif S.M.Ghoneim Waleed El Nahal 《Computers, Materials & Continua》 SCIE EI 2022年第6期4391-4408,共18页
This paper introduced an efficient compression technique that uses the compressive sensing(CS)method to obtain and recover sparse electrocardiography(ECG)signals.The recovery of the signal can be achieved by using sam... This paper introduced an efficient compression technique that uses the compressive sensing(CS)method to obtain and recover sparse electrocardiography(ECG)signals.The recovery of the signal can be achieved by using sampling rates lower than the Nyquist frequency.A novel analysis was proposed in this paper.To apply CS on ECG signal,the first step is to generate a sparse signal,which can be obtained using Modified Discrete Cosine Transform(MDCT)on the given ECGsignal.This transformation is a promising key for other transformations used in this search domain and can be considered as the main contribution of this paper.A small number of wavelet components can describe the ECG signal as related work to obtain a sparse ECGsignal.Asensing technique for ECGsignal compression,which is a novel area of research,is proposed.ECG signals are introduced randomly between any successive beats of the heart.MIT-BIH database can be represented as the experimental database in this domain of research.TheMIT-BIH database consists of various ECG signals involving a patient and standard ECG signals.MATLAB can be considered as the simulation tool used in this work.The proposed method’s uniqueness was inspired by the compression ratio(CR)and achieved by MDCT.The performance measurement of the recovered signal was done by calculating the percentage root mean difference(PRD),mean square error(MSE),and peak signal to noise ratio(PSNR)besides the calculation of CR.Finally,the simulation results indicated that this work is one of the most important works in ECG signal compression. 展开更多
关键词 Compressive sensing SPARSE beats of hearts compression ratio percentage root mean difference
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NOTES ON THE SPECTRAL PROPERTIES OF THE WEIGHTED MEAN DIFFERENCE OPERATOR G(u,v;?) OVER THE SEQUENCE SPACE ?_1
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作者 Vatan KARAKAYA Ezgi ERDOGAN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期477-486,共10页
In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1.... In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1. The product operator G (u, v; △) over l1 is defined by (G(u,v;△)x)k=^k∑i=0ukvi(xi- xi-1) with xk = 0 for all k 〈 0, where x = (xk)∈e1,and u and v axe either constant or strictly decreasing sequences of positive real numbers satisfying certain conditions. In this article we give some improvements of the computation of the spectrum of the operator G (u, v; △) on the sequence space gl. 展开更多
关键词 Spectrum of an operator weighted mean difference operator sequence space
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Acrylamide inhibits nerve sprouting induced by botulinum toxin type A
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作者 Hong Jiang Yi Xiang +1 位作者 Xingyue Hu Huaying Cai 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第16期1525-1531,共7页
Botulinum toxin type A is a potent muscle relaxant that blocks the transmission and release of acetylcholine at the neuromuscular junction. Intramuscular injection of botulinum toxin type A has served as an effective ... Botulinum toxin type A is a potent muscle relaxant that blocks the transmission and release of acetylcholine at the neuromuscular junction. Intramuscular injection of botulinum toxin type A has served as an effective and safe therapy for strabismus and focal dystonia. However, muscular weakness is temporary and after 3-4 months, muscle strength usually recovers because function- al recovery is mediated by nerve sprouting and reconstruction of the neuromuscular junction. Acrylamide may produce neurotoxic substances that cause retrograde necrotizing neuropathy and inhibit nerve sprouting caused by botulinum toxin type A. This study investigated whether acrylamide inhibits nerve sprouting after intramuscular injection of botulinum toxin type A. A tibial nerve sprouting model was established through local injection of botulinum toxin type A into the right gastrocnemius muscle of Sprague-Dawley rats. Following intramuscular injection, rats were given intraperitoneal injection of 3% acrylamide every 3 days for 21 days. Nerve sprout- ing appeared 2 weeks after intramuscular injection of botulinum toxin type A and single-fiber electromyography revealed abnormal conduction at the neuromuscular junction I week after intra- muscular injection of botulinum toxin type A. Following intraperitoneal injection of acrylamide, the peak muscle fiber density decreased. Electromyography jitter value were restored to normal levels 6 weeks after injection. This indicates that the maximal decrease in fiber density and the time at which functional conduction of neuromuscular junction was restored were delayed. Addition- ally, the increase in tibial nerve fibers was reduced. Acrylamide inhibits nerve sprouting caused by botulinum toxin type A and may be used to prolong the clinical dosage of botulinum toxin type A. 展开更多
关键词 nerve regeneration peripheral nerve regeneration botulinum toxin type A ACRYLAMIDE nerve sprouting ELECTROMYOGRAPHY nerve fibers neuromuscular junction single-fiber EMG fiberdensity action potential mean consecutive difference dysmyotonia neural regeneration
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An Improved Rate Control Method Based on Modification at Scene Change for H.264
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作者 RU Guobao GAO Wenli FU Jianfeng 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1047-1050,共4页
This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocatio... This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocation and quantization parameters are adjusted, using a certain threshold. In addition, the calculation of the mean absolute difference (MAD) is modified in an alternative way, which makes the rate distortion optimization (RDO) more accurate. Extensive simulation results show that the proposed method, compared with G012, can improve the average peak signal-to-noise ratio (PSNR) and moderate the image quality. 展开更多
关键词 brightness histogram mean absolute difference (MAD) rate distortion optimization (RDO) rate control scene change
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Mean Difference of Truncated Normal Distribution
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作者 Giovanni Girone Antonella Massari +1 位作者 Fabio Manca Claudia Marin 《Applied Mathematics》 2020年第11期1162-1166,共5页
The purpose of this paper is to broaden the knowledge of mean difference and, in particular, of an important distribution model known as truncated normal distribution, which is widely used in applied sciences and econ... The purpose of this paper is to broaden the knowledge of mean difference and, in particular, of an important distribution model known as truncated normal distribution, which is widely used in applied sciences and economics. In this work, we obtained the general formula of mean difference, which is not yet reported in literature, for the aforementioned distribution model and also for particular truncated cases. 展开更多
关键词 Mean Difference Truncated Normal Distribution Variability Indexes Economic Sciences
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Mean Difference and Mean Deviation of Tukey Lambda Distribution
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作者 Giovanni Girone Antonella Massari +1 位作者 Fabio Manca Angela Maria D’Uggento 《Applied Mathematics》 2020年第8期771-778,共8页
The purpose of this paper is to broaden the knowledge of mean difference and,<span><span><span style="font-family:;" "=""> </span></span></span><span sty... The purpose of this paper is to broaden the knowledge of mean difference and,<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in particular, of an important distribution model known as Tukey lambda, which is generally used to choose a model to fit data.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">We have obtained compact formulas, which are not yet reported in literature, of mean deviation and mean difference related to the said distribution model.</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">These results made it possible to analyze the relationships among variability indexes, namely standard deviation, mean deviation and mean difference, regarding Tukey lambda model.</span></span></span> 展开更多
关键词 Mean Difference Mean Deviation Tukey Lambda Distribution Variability Indexes’ Relationships
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A Simple Adaptive Rate Control for H.264/AVC
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作者 Myoung-Jin Kim Min-Cheol Hong 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期151-154,共4页
The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H.264/AVC rate control.In our scheme,we propose an enhancement method of ... The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H.264/AVC rate control.In our scheme,we propose an enhancement method of the target frame rate based H.264/AVC bit allocation.The enhancement uses a frame complexity estimation to improve the existing mean absolute difference(MAD)complexity measurement Bit allocation to each frame is not just computed by target frame rate but also adjusted by a combined frame complexity measure.Using the statistical characteristic,we obtain change of occurrence bit about QP to apply the bit amount by QP from the video characteristic and applied in the estimated bit amount of the current frame. Simulation results show that the proposed rate control scheme could not only achieves time saving of more than 99%over existing rate control algorithm,but also increase the average PSNR of reconstructed video for around 0.02~0.78 dB in all the sequences. 展开更多
关键词 H.264 Computational Complexity Mean Absolute Difference Rate Control Peak Signal-to-Noise Ration
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Adaptive Rate Control Scheme for H.264/AVC
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作者 Myoung-jin KIM Min-cheol HONG 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期192-195,共4页
The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H. 264/AVC rate control. The scheme ImPoses an enhancement method of the ... The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H. 264/AVC rate control. The scheme ImPoses an enhancement method of the target frame rate based on H. 264/AVC bit allocation. The enhancement uses a frame complexion estimation to improve the existing Mean Absolute Difference (MAD) complexity measurement. Bit allocation to each frame is not just computed by target frame rote but also adjusted by a combined frame complexity measure. Using the statistical characteristic, the scheme obtains change of occurrence bit about QP to apply the bit amount by QP from the video characteristic and apply it in the estimated bit amount of the current frame. Simulation results show that the proposed rate eontrol scheme achieves time saving of mine than 99% over existing rate control algorithm. Nevertheless, Peak Signal-to-Noise Ration (PSNR) and bit rate were almost the same as the performances. 展开更多
关键词 computational complexity Mean Absolute Difference rote control Peak Signal-to-Noise Ration
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Performance of Dexcom G5 and FreeStyle Libre sensors tested simultaneously in people with type 1 or 2 diabetes and advanced chronic kidney disease
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作者 Arndís FinnaÓlafsdóttir Mervi Andelin +4 位作者 Aso Saeed Sheyda Sofizadeh Hussein Hamoodi Per-Anders Jansson Marcus Lind 《World Journal of Clinical Cases》 SCIE 2022年第22期7794-7807,共14页
BACKGROUND Advanced chronic kidney disease(CKD) is a common complication for people with type 1 and 2 diabetes and can often lead to glucose instability. Continuous glucose monitoring(CGM) helps users monitor and stab... BACKGROUND Advanced chronic kidney disease(CKD) is a common complication for people with type 1 and 2 diabetes and can often lead to glucose instability. Continuous glucose monitoring(CGM) helps users monitor and stabilize their glucose levels. To date, CGM and intermittent scanning CGM are only approved for people with diabetes but not for those with advanced CKD.AIM To compare the performance of Dexcom G5 and FreeStyle Libre sensors in adults with type 1 or 2 diabetes and advanced CKD.METHODS This was a non-randomized clinical trial that took place in two outpatient clinics in western Sweden. All patients with type 1 or 2 diabetes and an estimated glomerular filtration rate(eGFR) of < 30 mL/min per 1.73 m^(2) were invited to participate. Forty patients(full analysis set = 33) carried the Dexcom G5 sensor for 7 d and FreeStyle Libre sensor for 14 d simultaneously. For referencing capillary blood glucose(SMBG) was measured with a high accuracy glucose meter(HemoCue®) during the study period. At the end of the study, all patients were asked to answer a questionnaire on their experience using the sensors.RESULTS The mean age was 64.1(range 41-77) years, hemoglobin A1 c was 7.0% [standard deviation(SD) 3.2], and diabetes duration was 28.5(SD 14.7) years. A total of 27.5% of the study population was on hemodialysis and 22.5% on peritoneal dialysis. The mean absolute relative difference for Dexcom G5 vs SMBG was significantly lower than that for FreeStyle Libre vs SMBG [15.2%(SD 12.2) vs 20.9%(SD 8.6)], with a mean difference of 5.72 [95% confidence interval(CI): 2.11-9.32;P = 0.0036]. The mean absolute difference was also significantly lower for Dexcom G5 than for FreeStyle Libre, 1.21 mmol/L(SD 0.78) and 1.76 mmol/L(SD 0.78), with a mean diffrenec of 0.55(95%CI: 0.27-0.83;P = 0.0004).The mean difference(MD) was-0.107 mmol/L and-1.10 mmol/L(P = 0.0002), respectively. In all, 66% of FreeStyle Libre values were in the no risk zone on the surveillance error grid compared to 82% of Dexcom G5 values.CONCLUSION Dexcom G5 produces more accurate sensor values than FreeStyle Libre in people with diabetes and advanced CKD and is likely safe to be used by those with advanced CKD. 展开更多
关键词 Type 1 diabetes Type 2 diabetes Chronic kidney disease Continuous glucose monitoring ACCURACY Mean absolute relative difference
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On the Mean Difference Variance in Random Samples of Student’s Variables
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作者 Manca Fabio Marin Claudia 《Open Journal of Statistics》 2020年第4期659-663,共5页
The purpose of this paper is to obtain the expression of the sample mean difference variance of the Student’s distributive model. In the 2007 the study of the mean difference variance, after some decades, was resumed... The purpose of this paper is to obtain the expression of the sample mean difference variance of the Student’s distributive model. In the 2007 the study of the mean difference variance, after some decades, was resumed by Campobasso</span><span style="font-family:Verdana;"> [1]</span><span style="font-family:Verdana;">. Using the Nair’s </span><span style="font-family:Verdana;">[2]</span><span style="font-family:Verdana;"> and Lomnicki’s general results</span><span style="font-family:Verdana;"> [3]</span><span style="font-family:Verdana;">, he obtained the variance of sample mean difference for different distributive models (Laplace</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s, triangular, power, logit, Pareto</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s and Gumbel’s model). In addition he extended the knowledge comparing to the ones already known for the other distributive model (normal, rectangular and exponential model). 展开更多
关键词 Mean Difference Variance Random Sample STUDENT
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The Mean Difference for Lognormal Distribution
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作者 Giovanni Girone Fabio Manca 《Applied Mathematics》 2016年第9期824-828,共5页
The calculation of the mean difference for the lognormal distribution involves several hard integrals featuring the error function. In this paper, considering two particular cases of an integral of the exponential fun... The calculation of the mean difference for the lognormal distribution involves several hard integrals featuring the error function. In this paper, considering two particular cases of an integral of the exponential function for the complement to one of the error functions, and using various symmetries, we have achieved the result of an extremely simple and useful formula of the mean difference for the lognormal distribution. 展开更多
关键词 Mean Difference Function Lognormal
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Inter-comparison of Raingauges on Rainfall Amount and Intensity Measurements in a Tropical Environment
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作者 Ying-wa Chan Choi-loi Yu Kwong-hung Tam 《Journal of Geodesy and Geomatics Engineering》 2015年第1期12-25,共14页
The HKO (Hong Kong Observatory) has been carrying out an inter-comparison of automatic raingauges since 2011 for identifying raingauges that can meet the ~ 5% accuracy requirement of the WMO (World Meteorological O... The HKO (Hong Kong Observatory) has been carrying out an inter-comparison of automatic raingauges since 2011 for identifying raingauges that can meet the ~ 5% accuracy requirement of the WMO (World Meteorological Organization) in measuring rainfall amount. The inter-comparison was conducted at HKO's meteorological stations at King's Park and Hong Kong International Airport in Hong Kong. Two 0.1-mm resolution Pluvio-OTT weighing gauges were introduced in 2013. This type of raingauges has outperformed others in the WMO's field inter-comparison held between October 2007 and April 2009. The performances of 14 raingauges, comprising five different measurement methods, viz. drop-counting, weighing, tipping bucket with software correction, tipping bucket with extra pulse correction and tipping bucket without correction, were evaluated. The focus was to study their performances in rainfall intensity measurement, especially during heavy rain situations. Different high rainfall intensity episodes were selected for analysis. Among these episodes, the maximum 1-minute rainfall intensity as high as around 130 mm/hr was recorded by the Pluvio-OTT raingauges. This paper serves to conclude the 3-year (2011-2013) inter-comparison exercise for rainfall amount measurements and to provide preliminary 1-year (2013) comparison results on rainfall intensity measurements. 展开更多
关键词 Automatic raingauges CALIBRATION rainfall intensity root mean square errors mean absolute percentage differences.
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A Method for Determining the Operable Ideal Condensation Temperature of Dry and Isentropic Fluids Used in Organic Rankine Cycle(ORC)Based on Temperature-Entropy(T-s)Diagram
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作者 ZHANG Xinxin LI Yang 《Journal of Thermal Science》 SCIE EI CAS CSCD 2023年第6期2144-2154,共11页
Condensation temperature is one of the crucial parameters determining the performance of an organic Rankine cycle.It is necessary to consider the differences in the working fluids themselves when setting the condensat... Condensation temperature is one of the crucial parameters determining the performance of an organic Rankine cycle.It is necessary to consider the differences in the working fluids themselves when setting the condensation temperature of organic Rankine cycle.In current study,temperature-entropy(T-s)diagram is employed to describe the difference in working fluids.Three areas of dry and isentropic fluids in a temperature-entropy(T-s)diagram,which are the area denoting net output work of cycle(A_(1),the area denoting net output work of the Carnot cycle(A),and the curved triangle in superheated region denoting condensation characteristics(A_(2)),are defined.On this basis,the ratio of A_(2)to A_(1)and the ratio of A_(1)to A are calculated.Logarithmic Mean Difference of the above two ratios is obtained to determine the operable ideal condensation temperature of 66 dry and isentropic fluids employed in Organic Rankine Cycle.The findings indicate that the operable ideal condensation temperatures for the majority of dry and isentropic fluids are in the range of 305 K to 310 K.The work presented in this study may be useful for designing and establishing an Organic Rankine Cycle system. 展开更多
关键词 organic Rankine cycle T-s(temperature-entropy)diagram condensation temperature dry f isentropic fluids logarithmic mean difference
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An adaptive fast search algorithm for block motion estimation in H.264
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作者 Cong-dao HAN 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2010年第8期637-644,共8页
Motion estimation is an important issue in H.264 video coding systems because it occupies a large amount of encoding time.In this paper,a novel search algorithm which utilizes an adaptive hexagon and small diamond sea... Motion estimation is an important issue in H.264 video coding systems because it occupies a large amount of encoding time.In this paper,a novel search algorithm which utilizes an adaptive hexagon and small diamond search (AHSDS) is proposed to enhance search speed.The search pattern is chosen according to the motion strength of the current block.When the block is in active motion,the hexagon search provides an efficient search means;when the block is inactive,the small diamond search is adopted.Simulation results showed that our approach can speed up the search process with little effect on distortion performance compared with other adaptive approaches. 展开更多
关键词 Adaptive hexagon and small diamond search (AHSDS) Search pattern Mean absolute difference (MAD) Optimal point
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The Role of Greenery, Layering, and Landmarks in the Regulations on Urban Skylines
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作者 Tatiana Orekhova Jiang LIANG 《China City Planning Review》 2014年第3期58-65,共8页
Many scholars have conducted visual analyses of urban skylines, but little attention has been paid to the quantitative measures regarding specific design elements within the skyline. This article aims to help urban de... Many scholars have conducted visual analyses of urban skylines, but little attention has been paid to the quantitative measures regarding specific design elements within the skyline. This article aims to help urban designers and regulators improve the skyline and investigate which factors can make urban skylines more pleasant for people. Computer generated images of skylines are tested for three factors including greenery, layering, and landmarks. For the data collection, a questionnaire was used, as one of the simple and effective methods to gather results. The authors use statistics as a method of measuring the degree of people's preferences. The study finds that the proportions of landmarks in the overall skyline, the height of layers, and the percentage of greenery deserve special attention. The authors also discuss the current problems of skyline design in typical Chinese cities according to the above findings. 展开更多
关键词 urban skyline greenery LAYERING LANDMARK visual analysis standardized mean difference
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