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Comparative Analysis of the Factors Influencing Metro Passenger Arrival Volumes in Wuhan, China, and Lagos, Nigeria: An Application of Association Rule Mining and Neural Network Models
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作者 Bello Muhammad Lawan Jabir Abubakar Shuyang Zhang 《Journal of Transportation Technologies》 2024年第4期607-653,共47页
This study explores the factors influencing metro passengers’ arrival volume in Wuhan, China, and Lagos, Nigeria, by examining weather, time of day, waiting time, travel behavior, arrival patterns, and metro satisfac... This study explores the factors influencing metro passengers’ arrival volume in Wuhan, China, and Lagos, Nigeria, by examining weather, time of day, waiting time, travel behavior, arrival patterns, and metro satisfaction. It addresses a significant research gap in understanding metro passengers’ dynamics across cultural and geographical contexts. It employs questionnaires, field observations, and advanced data analysis techniques like association rule mining and neural network modeling. Key findings include a correlation between rainy weather, shorter waiting times, and higher arrival volumes. Neural network models showed high predictive accuracy, with waiting time, metro satisfaction, and weather being significant factors in Lagos Light Rail Blue Line Metro. In contrast, arrival patterns, weather, and time of day were more influential in Wuhan Metro Line 5. Results suggest that improving metro satisfaction and reducing waiting times could increase arrival volumes in Lagos Metro while adjusting schedules for weather and peak times could optimize flow in Wuhan Metro. These insights are valuable for transportation planning, passenger arrival volume management, and enhancing user experiences, potentially benefiting urban transportation sustainability and development goals. 展开更多
关键词 Metro Passenger Arrival volume Influencing Factor Analysis Wuhan and Lagos Metro Neural Network Modeling Association Rule Mining Technique
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EFFECT OF IONIC RADII ON UNIT-CELL VOLUMES OF ISOSTRUCTURAL COMPOUNDS
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作者 张金民 叶大年 《Science China Chemistry》 SCIE EI CAS 1989年第8期1014-1024,共11页
The relation between cell-edges or unit-cell volumes of isostructural compounds and theionic radii has wide applications in crystal chemistry. The authors have proved: (1) For a series of multiple isostructural compou... The relation between cell-edges or unit-cell volumes of isostructural compounds and theionic radii has wide applications in crystal chemistry. The authors have proved: (1) For a series of multiple isostructural compounds such as A_mB_n…X_p, when the anionand other cations are fixed, there exists the following relation between the unit-cell volume Vand the radius r_A of a certain cation such as A: V = (a + br_A)(r_X + r_A)~3 (a and b are constants). (2) For binary isostructural compounds A_mX_p, the above relation is reduced to V = k(r_X + r_A)~3 (k is a constant). (3) For binary isostructural compounds the relation between V and r_A^3 is approximatelylinear, and for multiple compounds, it is often curvilinear but still approximately linear whenthe variation of r_A is slight. As another approximation, a linear relation also exists betweenV and r_A for isostructural compounds. (4) The relation of ce1l-edge a vs. r_A is linear for binary isostructural compounds. Butno such a good linear relation exists for multiple isostructural compounds. 展开更多
关键词 ISOSTRUCTURAL COMPOUNDS unit-cell volumes IONIC RADII
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The Mechanism of Changes in Mantle Volume
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作者 Daoxiong Hu 《International Journal of Geosciences》 CAS 2024年第8期549-556,共8页
The crust floats above the mantle, and the volume change of the mantle is the driving force of crustal movement. The increase in mantle volume leads to crustal extensional movement, resulting in continental crust rupt... The crust floats above the mantle, and the volume change of the mantle is the driving force of crustal movement. The increase in mantle volume leads to crustal extensional movement, resulting in continental crust rupture and oceanic crust expansion. The decrease in mantle volume leads to crustal compression movement, resulting in continental crust superposition, folding, and oceanic crust subduction. The factors that contribute to the increase in mantle volume include a change in material state, where solid material in the mantle melts into liquid material. The factors leading to a decrease in mantle volume include: oceanic crust uplift, crustal crystallization, volcanic eruptions, magma intrusion, and hydrothermal upwelling. The change in mantle volume dominates the evolution pattern of the crust. When the mantle volume increases unidirectionally, the crust only has horizontally crystallized continental crust. When the volume of the mantle changes in both directions, blocky layered oceanic crust is formed. The expansion and subduction of oceanic crust, as well as the stretching and compression of continental crust, are the supporting mechanisms for changes in Earth’s surface area caused by changes in mantle volume. 展开更多
关键词 Earth Formation Mantle volume Crustal Movement
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A Number Theoretic Analysis of the Enthalpy, Enthalpy Energy Density, Thermodynamic Volume, and the Equation of State of a Modified White Hole, and the Implications to the Quantum Vacuum Spacetime, Matter Creation and the Planck Frequency
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作者 Michele Nardelli Amos S. Kubeka Alizera Amani 《Journal of Modern Physics》 2024年第1期1-50,共50页
In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Th... In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Theory, Ramanujan Recurring Numbers, DN Constant and String Theory, that enable us to extract the quantum geometrical properties of these thermodynamic equations and the implication to the quantum vacuum spacetime geometry of our early universe as they act as the constraints to the nature of quantum gravity of the universe. 展开更多
关键词 Number Theory Ramanujan Recurring Numbers DN Constant String Theory Loop Quantum Gravity Matter Creation Enthalpy Energy Density Thermodynamic volume ENTHALPY
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SOME INEQUALITIES ABOUT DUAL MIXED VOLUMES OF STAR BODIES 被引量:5
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作者 李小燕 冷岗松 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期505-510,共6页
The authors establish some inequalities about the dual mixed volumes of star bodies in Rn. These inequalities are the analogue in the Brunn-Minkowski theory of the inequalities of Marcus-Lopes and Bergstrom about symm... The authors establish some inequalities about the dual mixed volumes of star bodies in Rn. These inequalities are the analogue in the Brunn-Minkowski theory of the inequalities of Marcus-Lopes and Bergstrom about symmetric functions of positive reals. 展开更多
关键词 Brunn-Minkowski theory star bodies dual mixed volumes Aleksandrov Fenchel inequality.
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Lower-Dimensional Volumes and Kastler-Kalau-Walze Type Theorem for Manifolds with Boundary 被引量:3
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作者 王勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期38-42,共5页
In this paper,we define lower-dimensional volumes of spin manifolds with boundary.We compute thelower-dimensional volume Vol^((2,2)) for 5-dimensional and 6-dimensional spin manifolds with boundary and we also getthe ... In this paper,we define lower-dimensional volumes of spin manifolds with boundary.We compute thelower-dimensional volume Vol^((2,2)) for 5-dimensional and 6-dimensional spin manifolds with boundary and we also getthe Kastler-Kalau-Walze type theorem in this case. 展开更多
关键词 lower-dimensional volumes noncommutative residue for manifolds with boundary gravitationalaction for manifolds with boundary
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Application of prolonging small feeding volumes early in life to prevent of necrotizing enterocolitis in very low birth weight preterm infants 被引量:3
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作者 Qiu-fang Li Hua Wang +2 位作者 Dan Liu Yi Tang Xin-fen Xu 《International Journal of Nursing Sciences》 2016年第1期45-49,共5页
Objective:To study the effects of prolonging small feeding volumes early in life on the incidence of necrotizing enterocolitis(NEC)in very low birth weight(VLBW)preterm infants.Methods:A total of 128 VLBW infants who ... Objective:To study the effects of prolonging small feeding volumes early in life on the incidence of necrotizing enterocolitis(NEC)in very low birth weight(VLBW)preterm infants.Methods:A total of 128 VLBW infants who could not be breastfed were assigned into the experimental group(63 cases)and the control group(65 cases)using a random number table.The experiment group was fed 12 mL/(kg·d)on day 1 which was increased to 24 mL/(kg·d)for the first 10 study days.The control group was fed 12 mL/(kg·d)for the first 14e48 hours.Then,the feeding volume increased by 24-36 mL/(kg·d)up to 140e160 mL/(kg·d)and maintained until the 10th day after birth.The incidence of feeding intolerance and NEC,duration of hospitalization,time to full enteral feedings,incidence of intrahepatic cholestasis,and the levels of gastrin and motilin in serum were assessed.Results:The incidence of feeding intolerance was significantly lower in the experimental group compared with the control group(15.87% vs.33.84%).There was a significant reduction in the incidence of NEC between the experimental and control groups(7.9% vs.16% in the control group).Conclusion:A protocol that prolongs small feeding volumes early in life can reduce the incidence and severity of NEC,but still warrants further study. 展开更多
关键词 Infant formula Necrotizing enterocolitis Preterm infant Prolonging small feeding volumes Very low birth weight infant
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Volume sequences of characteristic atoms separated from experimental volumes of AuCu and AuCu_3 compounds 被引量:6
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作者 谢佑卿 刘心笔 +2 位作者 李晓波 彭红建 聂耀庄 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第6期1599-1617,共19页
The systematic science of alloys(SSA)is a framework of the total energy and total volume able to be separated.The volume sequences of characteristic atoms at the central sites of the basic clusters in the fcc-based Au... The systematic science of alloys(SSA)is a framework of the total energy and total volume able to be separated.The volume sequences of characteristic atoms at the central sites of the basic clusters in the fcc-based Au-Cu system are separated out from the experimental volumes of L10-AuCu and L12-AuCu3 compounds at room temperature only,by nine volume V-functions. From these volume sequences,the volumes,volumes of formation,ordering(excess)volumes and volume mismatch degrees of the L10-AuCu,L12-AuCu3 and L12-Au3Cu compounds,Au3Cu-,AuCu-and AuCu3-type ordered alloys with maximal ordering degree, and disordered Au1-xCux alloys are calculated.Among these functions,only ordering volumes of the compounds and ordered alloys obtained by the 6th V-function are negative,i.e.,the destruction of the superlattice is accompanied by an increase in volume,which is identical with the experimental results.Accompanying conclusions,the different descriptions of volumetric properties between traditional alloy theories and SSA framework are discussed. 展开更多
关键词 序列特征 体积性质 化合物 实验 原子 有序合金 统计声级 系统科学
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Volume sequences of characteristic atoms separated from experimental volumes of disordered Au(1-x)Cux alloys 被引量:4
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作者 XIE You-qing LI Xiao-bo +2 位作者 LIU Xin-bi PENG Hong-jian NIE Yao-zhuang 《材料科学与工程(中英文版)》 2009年第10期54-75,共22页
关键词 有序合金 序列分离 子序列 无序 实验 特征 体积性质 系统科学
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Effects of smoking on cerebral and ventricular volumes in healthy males
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作者 Hyun-Jun Kim Mi-Hyun Choi +9 位作者 Beob-Yi Lee Su-Jeong Lee Jae-Woong Yang Ji-Hye Kim Jin-Seung Choi Dong-Won Kang Jang-Yeon Park Jae-Hoon Jun Gye-Rae Tack Soon-Cheol Chung 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第1期72-75,共4页
Previous studies have reported decreased cerebral volume as a result of smoking. However, little is known about accompanying changes in ventricular volume for healthy subjects who smoke, although ventricular volume is... Previous studies have reported decreased cerebral volume as a result of smoking. However, little is known about accompanying changes in ventricular volume for healthy subjects who smoke, although ventricular volume is increased in patients with multiple sclerosis who smoke. The present study analyzed whether cerebral volume decreased with smoking through the use of magnetic resonance imaging. In addition, accompanying changes in ventricular volume that resulted from decreased cerebral volume and smoking were analyzed in healthy subjects. When multivariate analysis of covariance was performed by integrating the 2 age groups, aged 20-28 years and 40-49 years, with statistical significance, results showed that cerebral volume of smokers was smaller and ventricular volume was greater compared with the non-smokers. These findings suggest that ventricular volume changes could be utilized to characterize the effects of smoking. 展开更多
关键词 SMOKING cerebral and ventricular volumes magnetic resonance imaging
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Hippocampus and amygdala volumes in patients with vaginismus
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作者 Murad Atmaca Sema Baykara +3 位作者 Omer Ozer Sevda Korkmaz Unsal Akaslan Hanefi Yildirim 《World Journal of Psychiatry》 SCIE 2016年第2期221-225,共5页
AIM: To compare hippocampus and amygdala volumes of patients with vaginismus with those of healthy control subjects.METHODS: Magnetic resonance imaging was performed on ten patients with vaginismus and ten control sub... AIM: To compare hippocampus and amygdala volumes of patients with vaginismus with those of healthy control subjects.METHODS: Magnetic resonance imaging was performed on ten patients with vaginismus and ten control subjects matched for age and gender. Volumes of the hippocampus and amygdala were blindly measured. RESULTS: We found that the mean right amygdala volume of patients with vaginismus were smaller than that of the healthy controls. With regard to hippocampus volumes, the mean left and right hippocampus volumes were smaller than those of the healthy controls. CONCLUSION: Our present findings suggest that there have been hippocampus and amygdala structural abnormalities in patients with vaginismus. These changes provide the notion that vaginismus may be a fear-related condition. 展开更多
关键词 VAGINISMUS HIPPOCAMPUS AMYGDALA volumes PATIENTS
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Densities and excess molar volumes of mixtures containing diesel,biodiesel and alkanols at temperatures from 288.15 to 313.15 K
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作者 Sunita Malik Poonam Jangra Darolia +1 位作者 S.K.Garg V.K.Sharma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期198-207,共10页
The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and alcohols.The densities of binary diesel(2)+1-alkanols(C_(3) or C_(4))(3)and ternary Jatro... The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and alcohols.The densities of binary diesel(2)+1-alkanols(C_(3) or C_(4))(3)and ternary Jatropha curcas biodiesel(1)+diesel(2)+1-alkanols(C_(3)or C_(4))(3)blends have been reported over full range of composition at temperatures within range 288.15 to 313.15 K.Also densities of Jatropha curcas biodiesel(1)+diesel or 1-alkanols(C_(3) or C_(4))(2)blends have been measured at 313.15 K.Excess molar volumes,V^E,V^E_(123)of binary and ternary blends were calculated from the measured data and the derived properties were correlated to composition using Redlich-Kister equation.A reasonable agreement was found between the measured and estimated values.Further,densities and excess molar volumes data were reasoned to discuss molecular interactions taking into consideration effect of composition and temperature. 展开更多
关键词 Jatropha curcas biodiesel DIESEL ALCOHOLS Blends Density Excess molar volumes
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Preparation of patterned boron nanowire films with different widths of unit-cell and their field emission properties
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作者 张永欣 刘飞 +4 位作者 申承民 李军 邓少芝 许宁生 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期407-411,共5页
Large-area patterned films of boron nanowires(BNWs) are fabricated at various densities by chemical vapor deposition(CVD). Different widths of unit-cell of Mo masks are used as templates. The widths of unit-cell o... Large-area patterned films of boron nanowires(BNWs) are fabricated at various densities by chemical vapor deposition(CVD). Different widths of unit-cell of Mo masks are used as templates. The widths of unit-cell of Mo masks are100 μm, 150 μm, and 200 μm, respectively. The distance between unit cells is 50 μm. The BNWs have an average diameter of about 20 nm and lengths of 10 μm–20 μm. High-resolution transmission electron microscopy analysis shows that each nanowire has a β-tetragonal structure with good crystallization. Field emission measurements of the BNW films show that their turn-on electric fields decrease with width of unit-cell increasing. 展开更多
关键词 patterned boron nanowires different width of unit-cell field emission properties
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Role of cardiac CTA in estimating left ventricular volumes and ejection fraction 被引量:4
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作者 Robin Man Singh Balkrishna Man Singh Jawahar Lal Mehta 《World Journal of Radiology》 CAS 2014年第9期669-676,共8页
Left ventricular ejection fraction(LVEF)is an impor-tant predictor of cardiac outcome and helps in makingimportant diagnostic and therapeutic decisions suchas the treatment of different types of congestive heartfailur... Left ventricular ejection fraction(LVEF)is an impor-tant predictor of cardiac outcome and helps in makingimportant diagnostic and therapeutic decisions suchas the treatment of different types of congestive heartfailure or implantation of devices like cardiac resynchro-nization therapy-defibrillator.LVEF can be measuredby various techniques such as transthoracic echo-cardiography,contrast ventriculography,radionuclidetechniques,cardiac magnetic resonance imaging andcardiac computed tomographic angiography(CTA).Thedevelopment of cardiac CTA using multi-detector rowCT(MDCT)has seen a very rapid improvement in thetechnology for identifying coronary artery stenosis andcoronary artery disease in the last decade.During theacquisition,processing and analysis of data to studycoronary anatomy,MDCT provides a unique opportunityto measure left ventricular volumes and LVEF simulta-neously with the same data set without the need foradditional contrast or radiation exposure.The develop-ment of semi-automated and automated software to measure LVEF has now added uniformity,efficiency and reproducibility of practical value in clinical practice rather than just being a research tool.This article will address the feasibility,the accuracy and the limitations of MDCT in measuring LVEF. 展开更多
关键词 STROKE volume VENTRICULAR EJECTION FRACTION COMPUTERIZED tomography X RAY
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Comparison between Neural Network and Adaptive Neuro-Fuzzy Inference System for Forecasting Chaotic Traffic Volumes
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作者 Jiin-Po Yeh Yu-Chen Chang 《Journal of Intelligent Learning Systems and Applications》 2012年第4期247-254,共8页
This paper applies both the neural network and adaptive neuro-fuzzy inference system for forecasting short-term chaotic traffic volumes and compares the results. The architecture of the neural network consists of the ... This paper applies both the neural network and adaptive neuro-fuzzy inference system for forecasting short-term chaotic traffic volumes and compares the results. The architecture of the neural network consists of the input vector, one hidden layer and output layer. Bayesian regularization is employed to obtain the effective number of neurons in the hidden layer. The input variables and target of the adaptive neuro-fuzzy inference system are the same as those of the neural network. The data clustering technique is used to group data points so that the membership functions will be more tailored to the input data, which in turn greatly reduces the number of fuzzy rules. Numerical results indicate that these two models have almost the same accuracy, while the adaptive neuro-fuzzy inference system takes more time to train. It is also shown that although the effective number of neurons in the hidden layer is less than half the number of the input elements, the neural network can have satisfactory performance. 展开更多
关键词 NEURAL Network Adaptive NEURO-FUZZY INFERENCE System CHAOTIC TRAFFIC volumes State Space Reconstruction
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Determination of Partial Molar Volumes of EPA and DHA Ethyl Esters in Supercritical Carbon Dioxide 被引量:6
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作者 Mei HUANG Xian Da WANG +2 位作者 Ren Tian XIONG Ping Dong WU Qi Long REN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第1期83-86,共4页
The use of supercritical-fluid chromatography for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis -4,7,10,13,16,19- docosa-hexaenoic acid (DHA) in supercritica... The use of supercritical-fluid chromatography for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis -4,7,10,13,16,19- docosa-hexaenoic acid (DHA) in supercritical carbon dioxide is presented and discussed. Partial molar volumes of EPA and DHA esters are obtained from the variation of the retention properties with the density of mobile phase at 313.15 K, 323.15 K, 333.15 K and in the pressure range from 9 MPa to 21 MPa. 展开更多
关键词 EPA and DHA capacity factor partial molar volume supercritical-fluid chromatography.
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Systematic Evaluation of Current Possibilities to Determine Left Ventricular Volumes by Echocardiography in Patients after Myocardial Infarction
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作者 Stephan Stoebe Adrienn Tarr +2 位作者 Tudor Trache Jens-Gerrit Kluge Dietrich Pfeiffer 《Open Journal of Medical Imaging》 2012年第2期68-75,共8页
Purpose: The aim of the present study was to evaluate the diagnostic accuracy for quantification of left ventricular (LV) volumes and LV ejection fraction (LVEF) with current echocardiographic methods of planimetry fo... Purpose: The aim of the present study was to evaluate the diagnostic accuracy for quantification of left ventricular (LV) volumes and LV ejection fraction (LVEF) with current echocardiographic methods of planimetry for analysis of LV remodeling after myocardial infarction in daily clinical routine. Methods: 26 patients were investigated directly after interventional therapy at hospital pre-discharge and at 6 month follow-up. Standardized 2D transthoracic native and contrast echocardiography were performed in all patients. Due to methodological aspects the results of LV volumes and LVEF using native echocardiography were compared to the results of LV opacification (LVO) imaging for analysis in mono-, bi- and triplane data sets using the Simpson’s rule. In addition corresponding multidimensional data sets were analyzed. Results: The assessment of LV volumes and LVEF is more accurate with contrast echocardiography. The comparison of LV volumes and LVEF shows significant increases using contrast echocardiography (p < 0.001). Larger left ventricular end-diastolic volumes (LVEDV) are measured at follow up (p < 0.05). Significant differences (p < 0.001) are found for the determination of LVEDV and LVEF relating to apical mono-, bi-, tri- and multiplane data sets. Standard deviations of the triplane approach, however, are significantly lower than using other modalities. Conclusion: Depending on the localization of the myocardial infarction LV volumes and LVEF are less reliably evaluated using the mono- or biplane approach. According to standardization and simultaneous acquisition of all LV wall segments the triplane approach is currently the best approach to determine LV systolic function. In addition, contrast echocardiography is indicated to improve endocardial border delineation in patients using the triplane or multiplane approach. To our knowledge the present study is the first systematic evaluation of all current possibilities for determination of LV volumes and LVEF by native and contrast echocardiography. 展开更多
关键词 Contrast ECHOCARDIOGRAPHY LEFT VENTRICULAR SYSTOLIC Function LEFT VENTRICULAR volumes Remodeling Myocardial INFARCTION LVO Imaging
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Equal Volumes of Sand and Gravel Concrete Mix Ratios in Cameroon and Its Effect on Concrete Compressive Strength
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作者 Patrick Bame Che Yamb Bell Emmanuel Ndigui Billong 《World Journal of Engineering and Technology》 2022年第3期539-549,共11页
In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of thi... In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of this study is therefore to investigate if the concrete produced with rationalized mix ratio can be adopted as conventional mix ratio in terms of minimum required compression strength of concrete for buildings. Specifically this work compared the conventional mix ratio of 350 kg of cement: 400 liters of sand: 800 liters of gravel for a cubic meter and the rationalized batch of 350 kg of cement: 600 liters of sand: 600 liters of 5/15 gravel, 15/25 gravel and a combination of 5/15 + 15/25 gravel. Average compressive tests’results for both the conventional and the rationalized mix ratios were found to meet the minimum compressive strength of 65% at 7 days, 90% at 14 days and 99% at 28 days for gravel size combination 5/15 + 15/25. Single size gravel of 5/15 and 15/25 did not meet the minimum required compressive strength of 20 N/mm<sup>2</sup> for the rationalized mix ratio at 28 days curing based on the minimum compressive strength required, this study arrives at the conclusion that the equal volumes of sand and gravel mix ratio of 350 kg/m<sup>3</sup> of cement: 600 liters of sand: 600 liters of gravel mix ratio can be adopted as a conventional concrete mix ratio for gravel size 5/15 + 15/25. 展开更多
关键词 Conventional Concrete Rationalized Concrete Mix Ratio Compressive Strength Equal volumes of Sand and Gravel
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Apparent Molar Volumes and Solvation Coefficients in Ternary-pseudo-binary Mixtures [(Styrene+Ethyl Acetate or Benzene)+(N-Methyl-2-pyrrolidone+Ethyl Acetate or Benzene)] 被引量:2
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作者 HOU Hai-yun PENG San-jun +1 位作者 WANG Sheng-ze GENG Xing-peng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期309-317,共9页
Over the full range of compositions, in the ternary-pseudo-binary mixtures of x[(1-y)C6H5CH=CH2+ yCH3COOC2H5(or C6H6)]+(1-x)[(1-y)NMP+yCH3COOC2Hs(or C6H6)], the apparent molar volumes of each pseudo-pure ... Over the full range of compositions, in the ternary-pseudo-binary mixtures of x[(1-y)C6H5CH=CH2+ yCH3COOC2H5(or C6H6)]+(1-x)[(1-y)NMP+yCH3COOC2Hs(or C6H6)], the apparent molar volumes of each pseudo-pure component at different y values were calculated from the density data at 298.15 K and atmospheric pressure. The results show that the four parameters cubic polynomial can correlate the apparent molar volume with the molar fraction well over the full molar fraction range. The limiting partial molar volumes and the molar volumes of each pseudo-pure component were evaluated with different methods. Based on the limiting partial molar volume and molar volume at a certain y value, a new universal coefficient termed as solvation coefficient γ was defined to describe quantitatively the solvation degree of pseudo-pure solute and the interactions of solute-solvent molecules from the macroscopical thermodynamics viewpoint. The results demonstrate the solvation coefficients decrease with the amount of the third component increasing for each pseudo-pure solute, irrespective of the pseudo-pure solvent. Then the solvation degrees of each pseudo-pure component, the specific interactions between the solute molecule and the solvent one were discussed in terms of the solvation coefficient. 展开更多
关键词 Apparent molar volume Ternary-pseudo-binary mixture Solvation coefficient
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Analysis of the dynamic characteristics and stochastic simulation on variations of beach volumes 被引量:8
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作者 Chen Zishen(Institute of Estuarine and Coastal Research of Zhongshan University, Guangzhou 510275, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1995年第3期393-403,共11页
This paper analyzes the dynamic characteristics of the variations of the beach volumes for three level zonesof the Yanjing Beach in the Shuidong Bay of the western Guangdong Province by using the methods of dynamic sy... This paper analyzes the dynamic characteristics of the variations of the beach volumes for three level zonesof the Yanjing Beach in the Shuidong Bay of the western Guangdong Province by using the methods of dynamic systemanalysis and the multi-dimensional spectral estimation. The results show that the variations of the beach volume arecharaCterized by the multiband oscillations with a dominant semimonth period. Upwards the low tide level, the beachtends to be stable. The estimates of the partial coherences and the partial phases indicate that the variations of thebeach volumes are mainly the results of the direct actions of the waves which are influenced by the tidal level changesand driven by the wind stress. The simulation results of the beach volume series for different beach heart zones bythreshold mixed regressive models indicate that the influence of the tide on the variations of the beach volumes is weakened and the direct actions of the wave energy and the wind stress are apparently enhanced with the increase of thebeach height.(This project was supported by the National Natural Science Foundation of China.) 展开更多
关键词 Beach volume variations natural frequency damping ratio multi-dimensional spectral estimation stochastic simulation
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