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Corrections of shipboard GPS radiosonde soundings and applications on historical records in the eastern tropical Indian Ocean and South China Sea
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作者 Zewen Wu Xin Liu +3 位作者 Yunkai He Haoyu Jiang Bo Peng Ke Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期54-69,共16页
Shipboard radiosonde soundings are important for detecting and quantifying the multiscale variability of atmosphere-ocean interactions associated with mass exchanges.This study evaluated the accuracies of shipboard Gl... Shipboard radiosonde soundings are important for detecting and quantifying the multiscale variability of atmosphere-ocean interactions associated with mass exchanges.This study evaluated the accuracies of shipboard Global Positioning System(GPS)soundings in the eastern tropical Indian Ocean and South China Sea through a simultaneous balloon-borne inter-comparison of different radiosonde types.Our results indicate that the temperature and relative humidity(RH)measurements of GPS-TanKong(GPS-TK)radiosonde(used at most stations before 2012)have larger biases than those of ChangFeng-06-A(CF-06-A)radiosonde(widely used in current observation)when compared to reference data from Vaisala RS92-SGP radiosonde,with a warm bias of 5℃and dry bias of 10%during daytimes,and a cooling bias of-0.8℃and a moist bias of 6%during nighttime.These systematic biases are primarily attributed to the radiation effects and altitude deviation.An empirical correction algorithm was developed to retrieve the atmospheric temperature and RH profiles.The corrected profiles agree well with that of RS92-SGP,except for uncertainties of CF-06-A in the stratosphere.These correction algorithms were applied to the GPS-TK historical sounding records,reducing biases in the corrected temperature and RH profiles when compared to radio occultation data.The correction of GPS-TK historical records illustrated an improvement in capturing the marine atmospheric structure,with more accurate atmospheric boundary layer height,convective available potential energy,and convective inhibition in the tropical ocean.This study contributes significantly to improving the quality of GPS radiosonde soundings and promotes the sharing of observation in the eastern tropical Indian Ocean and South China Sea. 展开更多
关键词 shipboard GPS radiosonde soundings CORRECTIONS temperature relative humidity eastern tropical Indian Ocean South China Sea
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Reciprocity Relation between the Mass Constituents of the Universe and Hardy’s Quantum Entanglement Probability 被引量:2
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作者 Hans Hermann Otto 《World Journal of Condensed Matter Physics》 2018年第2期30-35,共6页
In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-t... In this short contribution, a reciprocity relation between mass constituents of the universe was explained governed by Hardy’s maximum entanglement probability of φ5 = 0.09017. While well explainable through a set-theoretical argumentation, the relation may also be a consequence of a coupling factor attributed to the normed dimensions of the universe. Also, very simple expressions for the mass amounts were obtained, when replacing the Golden Mean φ by the Archimedes’ constant π. A brief statement was devoted to the similarity between the E-Infinity Theory of El Naschie and the Information Relativity Theory of Suleiman. In addition, superconductivity was also linked with Hardy’s entanglement probability. 展开更多
关键词 UNIVERSE MASS Constituents Golden Mean Archimedes’ Constant RECIPROCITY RELATION E-INFINITY theORY Information Relativity theORY Entanglement Superconductivity
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Lexical Relations: Measuring the Proficiency of the Saudi EFL Learners and Analysing the Obstacles
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作者 Nisreen Juma'a Hamed Al-Mashaqba 《Sino-US English Teaching》 2017年第3期175-186,共12页
As teachers of EFL (English as a Foreign Language) in the Kingdom of Saudi Arabia, we are sometimes flabbergasted by the errors that the/earners make in their English scripts. Apparently, there was no pattern to the... As teachers of EFL (English as a Foreign Language) in the Kingdom of Saudi Arabia, we are sometimes flabbergasted by the errors that the/earners make in their English scripts. Apparently, there was no pattern to these errors. However, when the researcher observed the frequency of similar error over a few years of her experience as an EFL faculty for Saudi learners, the theory of Lexical Relations appeared to offer an answer. Therein also lies the genesis of the current study. In a positive development, the study did bring to light certain factors that directly played a role in the Saudi EFL learners' English errors. These have been presented in this paper with the hope that with the diagnosis in hand, it will be easier for the EFL teachers to find a solution to the dearth of English proficiency among the Saudi EFL learners. 展开更多
关键词 words meanings lexis lexical relations lexical choice
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The Esthetic Connection between Chorus Voice and “Form”
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作者 Kehan Teng 《Journal of Contemporary Educational Research》 2019年第1期24-30,共7页
Music is the art of sound,while chorus is the art of group vocal music.Choral art takes human voice as the carrier to express thoughts,emotions,and artistic images through sound.Harmonious,unified,balanced sound gives... Music is the art of sound,while chorus is the art of group vocal music.Choral art takes human voice as the carrier to express thoughts,emotions,and artistic images through sound.Harmonious,unified,balanced sound gives people the enjoyment of beauty and brings people-related pictorial association.As a unique form of vocal music art,chorus is also a comprehensive stage art belonging to the category of performance,which is a sister art belonging to the same and different families,such as dance and drama.In the visual arts such as dance and drama,the melody,timbre,and harmony of music match the figures appearing on the stage or screen.So that when we hear some kind of music there will belyrical beautiful,strong magnificent,or lively jumping,dark melancholy and so on feelings and associations.From ancient to modern times,in daily life,people sang and danced scenes were also their immediate reflection of music aesthetic feelings.Some of these aesthetic experiences are vague and some are specific.For example:We may think some music is humorous or sad,but when people hear the music,such as"the devil into the village",we will think of the scene in that movie.Which associated the Anti-Japanese War.In chorus,the influence of“form”on the aesthetic feeling of sound,or from the perspective of reverse thinking,canbe said to be the aesthetic expression of“form”by sound,which can relate to the breath of singing,the resonance position and the effect and change of the expression state.The audience can feel the chorus’s expression of aesthetic emotion directly from their hearing and then has a significant influence on the music sound and singing effect.In this paper,through the association of“form”to sound and aesthetic influence,with the help of some in the dance to tighten the intuitive posture,to chorus vertical sound insporation.Starting from the identity of visual perception and sound perception,this paper tries to understand our requirements for chorus singing from a reverse perspective.To maintain the breath of the chorus sound,to control the state,to establish the sound of harmony,unity and balance,as well as the performance of the overall sound effect,etc,to make a different angle of interpretation. 展开更多
关键词 CHORUS sound“form” AUDITORY perceptual style AEStheTIC RELATION
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Cross-sectional Anatomy and Clinical Meanings of the Extraocular Muscles and Related Structures in Orbit
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作者 Jin-Ping LIU~1 Yun-Sheng LI~1 Kan-Xing ZHAO~(2Δ) Heng SHAO~1 Xue-Han QIAN~2 Jian-Sheng ZHI~11(Department of Anatomy, Tianjin Medical University, Tianjin 300070, China)2(Tianjin Eye Hospital, Tianjin 300040, China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期37-38,共2页
关键词 Cross-sectional Anatomy and Clinical meanings of the Extraocular Muscles and Related Structures in Orbit
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How to Deal with New Words in Material——What is a Word and its Relations to the Reading
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作者 宣洪芝 《海外英语》 2015年第11期232-235,共4页
When you mention lexicology,absolutely it is a branch of linguistics,inquiring into the origins and meanings of words.The lexicologist Mc Carthy(1990)have given us his opinion about it.He said,grammar is important,and... When you mention lexicology,absolutely it is a branch of linguistics,inquiring into the origins and meanings of words.The lexicologist Mc Carthy(1990)have given us his opinion about it.He said,grammar is important,and it indeed plays a vital rolein English study,but that is not all.In fact,tar from this.From this we can see,vocabulary and the study and learning of vocabularytake an outstanding place in the study of language,it will improve his skills of using reference books and raise his problem-solvingability and efficiency of individual study.And it will make you much more receptive and productive in language processing and lan-guage production.Knowledge of English Lexicology can offer a great help to the work of the teachers of English.Armed with thisknowledge,they can better control the teaching materials,especially the concerning words.They can also select and organize mate-rials to teach in a more effective way.What is more,they can make use of the different sense relations to group vocabulary,inter-pret words and explain meanings to the students;At last,their teaching will prove better if they have the knowledge of dictionaries.In my thesis,I will talk about how to deal with new words in material. 展开更多
关键词 LEXICOLOGY vocabulary new WORDS DEAL with language MEANING relation
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Dissociation of the N400 component between linguistic and non-linguistic processing: A source analysis study
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作者 Anne Gallagher Renée Béland +5 位作者 Phetsamone Vannasing Maria Luisa Bringas Pedro Valdes Sosa Nelson J. Trujillo-Barreto John Connolly Maryse Lassonde 《World Journal of Neuroscience》 2014年第1期25-39,共15页
The N400 component is commonly associated with the detection of linguistic incongruity. A few studies have shown that the N400 can also be elicited by non-linguistic stimuli. Different spatiotemporal patterns were obs... The N400 component is commonly associated with the detection of linguistic incongruity. A few studies have shown that the N400 can also be elicited by non-linguistic stimuli. Different spatiotemporal patterns were observed between the typical Linguistic N400 and the Non-linguistic N400, suggesting distinct brain generators. The aim of this study was to investigate the presence of an N400 in response to linguistic and non-linguistic stimuli, and to specify anatomical sources of both N400s using a novel analysis method: the Bayesian Model Averaging (BMA) distributed source model. Picture-word and environmental soundpicture associations, either congruent or incongruent, were presented to ten young healthy adults while highdensity ERP recordings were made. Standard electrophysiological analyses confirmed that the N400 was not specific to linguistic incongruity but was also elicited by environmental sound-picture incongruities. Different topographic distributions were obtained for the Linguistic N400 and Non-linguistic N400. BMA analysis showed that the Linguistic N400 generators were mostly located in the left superior temporal gyrus, whereas the sources of the Non-linguistic N400 were identified mostly in the right middle and superior temporal gyri. Detection of linguistic incongruities recruited cerebral areas commonly associated with language processing, whereas non-linguistic incongruities recruited right cerebral regions usually associated with auditory processing of non-linguistic stimuli. The Linguistic and Non-linguistic N400s appear to be elicited by similar cognitive mechanisms assumed by different cerebral areas depending on the type of material to be processed. The present findings support the existence of parallel pathways for the processing of linguistic and non-linguistic incongruities. 展开更多
关键词 EVENT-RELATED Potentials INCONGRUITY Semantic Environmental sounds Distributed Source Model BMA
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RIGHT MEAN FOR THEα-z BURES-WASSERSTEIN QUANTUM DIVERGENCE
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作者 Miran JEONG Jinmi HWANG Sejong KIM 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2320-2332,共13页
The optimization problem to minimize the weighted sum ofα-z Bures-Wasserstein quantum divergences to given positive definite Hermitian matrices has been solved.We call the unique minimizer theα-z weighted right mean... The optimization problem to minimize the weighted sum ofα-z Bures-Wasserstein quantum divergences to given positive definite Hermitian matrices has been solved.We call the unique minimizer theα-z weighted right mean,which provides a new non-commutative version of generalized mean(H?lder mean).We investigate its fundamental properties,and give many interesting operator inequalities with the matrix power mean including the Cartan mean.Moreover,we verify the trace inequality with the Wasserstein mean and provide bounds for the Hadamard product of two right means. 展开更多
关键词 Rényi relative entropy Bures-Wasserstein quantum divergence right mean power mean Cartan mean Wasserstein mean
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Sea Surface Effects on Sound Scattering in the Persian Gulf Region Based on Empirical Relations 被引量:2
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作者 Parviz Ghadimi Alireza Bolghasi Mohammad A. Feizi Chekab 《Journal of Marine Science and Application》 CSCD 2015年第2期113-125,共13页
In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogde... In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine's experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine's scattering relation which consists of perturbation theory and Chapman-Harris's scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase. 展开更多
关键词 surface scattering strength scattered intensity seasurface effects Persian Gulf sound scattering empirical relation perturbation theory
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THE PROXIMAL RELATION,REGIONALLY PROXIMAL RELATION AND BANACH PROXIMAL RELATION FOR AMENABLE GROUP ACTIONS
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作者 Yuan LIAN Xiaojun HUANG Zhiqiang LI 《Acta Mathematica Scientia》 SCIE CSCD 2021年第3期729-752,共24页
In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group actions.A useful tool is the support of a topological dynamic... In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group actions.A useful tool is the support of a topological dynamical system which is used to study the structure of the Banach proximal relation,and we prove that above three relations all coincide on a Banach mean equicontinuous system generated by an amenable group action. 展开更多
关键词 Proximal relation amenable group mean equicontinuity
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THE INEFFICIENCY OF THE LEAST SQUARES ESTIMATOR AND ITS BOUND
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作者 杨虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第11期1087-1093,共7页
It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this... It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound. 展开更多
关键词 inefficiency relative efficiency mean squared error generalized variance matrix derivative best linear unbased estimator
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Galactic Route to the Strong Coupling Constant αs(mz) and Its Implication on the Mass Constituents of the Universe
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2022年第12期3572-3585,共14页
Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum g... Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum galactic rotation velocity by the simple relation , where is the velocity, at which the difference between galactic rotation velocity and Thomas precession is equal, and α is Sommerfeld’s constant. The result is in excellent agreement with the value of α<sub>s</sub> = 0.1170 ± 0.0019, recently measured and verified via QCE analysis by CERN researchers. One can formulate a reciprocity relation, connecting α<sub>s</sub> with the circle constant: . It is the merit of Preston Guynn to derive the Milky Way maximum value of the galactic rotation velocity β<sub>g</sub>, pointing to its “extremely important role in all physics”. The mass (energy) constituents of the Universe follow a golden mean hierarchy and can simply be related to the maximum of Guynn’s difference velocity respectively to α<sub>s</sub>(m<sub>z</sub>), therewith excellently confirming Bouchet’s WMAP data analysis. We conclude once more that the golden mean concept is the leading one of nature. 展开更多
关键词 Strong Coupling Constant Sommerfeld’ Constant Gravitational Coupling Constant Galactic Velocity Structure-Matter theory Reciprocity Relation Goldem Mean Hierarchy Mass and Energy Constituents of the Universe Superconductivity Matter-Antimatter Asymmetry Unification of Science
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Estimation of Population Variance Using the Coefficient of Kurtosis and Median of an Auxiliary Variable under Simple Random Sampling
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作者 Tonui Kiplangat Milton Romanus Otieno Odhiambo George Otieno Orwa 《Open Journal of Statistics》 2017年第6期944-955,共12页
In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an au... In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an auxiliary variable x. The estimator’s properties have been derived up to first order of Taylor’s series expansion. The efficiency conditions derived theoretically under which the proposed estimator performs better than existing estimators. Empirical studies have been done using real populations to demonstrate the performance of the developed estimator in comparison with the existing estimators. The proposed estimator as illustrated by the empirical studies performs better than the existing estimators under some specified conditions i.e. it has the smallest Mean Squared Error and the highest Percentage Relative Efficiency. The developed estimator therefore is suitable to be applied to situations in which the variable of interest has a positive correlation with the auxiliary variable. 展开更多
关键词 Modified Ratio Type Variance Estimator Study VARIABLE AUXILIARY VARIABLE KURTOSIS MEDIAN Bias Mean Squared Error (MSE) PERCENTAGE Relative Efficiency (PRE) Simple Random Sampling
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Constitutive relation of an orthorhombic polycrystal with the shape coefficients 被引量:10
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作者 Mojia Huang Zhiwen Lan Huiling Liang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期608-618,共11页
An orthorhombic polycrystal is an orthorhombic aggregate of tiny crystallites. In this paper, we study the effect of the crystalline mean shape on the constitutive relation of the orthorhombic polycrystal. The crystal... An orthorhombic polycrystal is an orthorhombic aggregate of tiny crystallites. In this paper, we study the effect of the crystalline mean shape on the constitutive relation of the orthorhombic polycrystal. The crystalline mean shape and the crystalline orientation arrangement are described by the crystalline shape function (CSF) and the orientation distribution function (ODF), respectively. The CSF and the ODF are expanded as an infinite series in terms of the Wigner D-functions. The expanded coefficients of the CSF and the ODF are called the shape coefficients s^lm0 and the texture coefficients c^lmn respectively. Assuming that Ceff in the constitutive relation depends on the shape coefficients s^lm0 and the texture coefficients c^lmn by the principle of material frame-indifference we derive an analytical expression for C^eff up to terms linear in s^lmo and c^lmn and the expression would be applicable to the polycrystal whose texture is weak and whose crystalline mean shape has weak anisotropy. C^cff contains six unspecified material constants (λ, μ, c, s1, s2, s3), five shape coefficients (s^2 00, s^2 20, s^4 00, s^4 20, s^4 40), and three texture coefficients (c^4 99,c^4 20, c^4 40), The results based on the perturbation approach are used to determine the five material constants approximately. We also find that the shape coefficients 2 and a s^2mo and s^4m0 are all zero if the crystalline mean shape is a cuboid. Some examples are given to compare our computational results. 展开更多
关键词 Crystalline mean shape Constitutive relation Orthorhombic polycrystal the shape coefficients the texture coefficients
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Interpreting Dose-Response Relation for Exposure to Multiple Sound Impulses in the Framework of Immunity 被引量:5
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作者 Hongyun Wang Wesley A. Burgei Hong Zhou 《Health》 2017年第13期1817-1842,共26页
Hearing loss is a common military health problem and it is closely related to exposures to impulse noises from blast explosions and weapon firings. In a study based on test data of chinchillas and scaled to humans (Mi... Hearing loss is a common military health problem and it is closely related to exposures to impulse noises from blast explosions and weapon firings. In a study based on test data of chinchillas and scaled to humans (Military Medicine, 181: 59-69), an empirical injury model was constructed for exposure to multiple sound impulses of equal intensity. Building upon the empirical injury model, we conduct a mathematical study of the hearing loss injury caused by multiple impulses of non-uniform intensities. We adopt the theoretical framework of viewing individual sound exposures as separate injury causing events, and in that framework, we examine synergy for causing injury (fatigue) or negative synergy (immunity) or independence among a sequence of doses. Starting with the empirical logistic dose-response relation and the empirical dose combination rule, we show that for causing injury, a sequence of sound exposure events are not independent of each other. The phenomenological effect of a preceding event on the subsequent event is always immunity. We extend the empirical dose combination rule, which is applicable only in the case of homogeneous impulses of equal intensity, to accommodate the general case of multiple heterogeneous sound exposures with non-uniform intensities. In addition to studying and extending the empirical dose combination rule, we also explore the dose combination rule for the hypothetical case of independent events, and compare it with the empirical one. We measure the effect of immunity quantitatively using the immunity factor defined as the percentage of decrease in injury probability attributed to the sound exposure in the preceding event. Our main findings on the immunity factor are: 1) the immunity factor is primarily a function of the difference in SELA (A- weighted sound exposure level) between the two sound exposure events;it is virtually independent of the magnitude of the two SELA values as long as the difference is fixed;2) the immunity factor increases monotonically from 0 to 100% as the first dose is varied from being significantly below the second dose, to being moderately above the second dose. The extended dose-response formulation developed in this study provides a theoretical framework for assessing the injury risk in realistic situations. 展开更多
关键词 Risk of Significant Injury Logistic DOSE-RESPONSE RELATION SELA (A-Weighted SOUND Exposure Level) Effective SELA for MULTIPLE Heterogeneous SOUND IMPULSES Fatigue and IMMUNITY
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The similitude research on underwater complex shell-structure based on SEA 被引量:1
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作者 WANGSan-de YANGDe-sen SHISheng-guo FANGEr-zheng 《Journal of Marine Science and Application》 2005年第1期54-59,共6页
In this paper, the vibration arid sound radiation of the underwater complexshell-structure which is the cylindrical shell with hemi-spherical shell on the ends are studied bystatistical energy analysis (SEA). The whol... In this paper, the vibration arid sound radiation of the underwater complexshell-structure which is the cylindrical shell with hemi-spherical shell on the ends are studied bystatistical energy analysis (SEA). The whole shell-structure is divided into the four subsystems,and the SEA physical model and power flow balance equations among these subsystems are established.The similitude relations of input power, coupling loss factor and modal density of the subsystemsbetween the complex shell-structure and its scaled-down model are analyzed. According to thesimilitude theory and power flow balance equations, when the immerged shell-structures are excited,the similar relations of spatially averaged vibration response and underwater radiating sound powerare established for the complex shell-structure and its scaled-down model. 展开更多
关键词 SEA similar relation sound radiation structural vibration
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Estimation of the Population Mean Using Paired Ranked Set Sampling
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作者 B. S. Biradar C. D. Santosha 《Open Journal of Statistics》 2015年第2期97-103,共7页
In the situation where the sampling units in a study can be easily ranked than quantified, the ranked set sampling methods are found to be more efficient and cost effective as compared to SRS. In this paper we propose... In the situation where the sampling units in a study can be easily ranked than quantified, the ranked set sampling methods are found to be more efficient and cost effective as compared to SRS. In this paper we propose an estimator of the population mean using paired ranked set sampling (RSS) method. The proposed estimator is an unbiased estimator of the population mean when the set size is even. In case of odd set size the estimator is unbiased when the underlying distribution is symmetric. It is shown that the proposed estimator is more efficient than its counterpart SRS method for all distributions considered in this study. 展开更多
关键词 Ranked SET Sampling Paired Ranked SET Sampling POPULATION Mean RELATIVE EFFICIENCY ERRORS in RANKING
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A Short-Term PV Power Forecasting Method Using a Hybrid Kmeans-GRA-SVR Model under Ideal Weather Condition 被引量:1
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作者 Jiemin Lin Haiming Li 《Journal of Computer and Communications》 2020年第11期102-119,共18页
With the continuous increase of solar penetration rate, it has brought challenges to the smooth operation of the power grid. Therefore, to make photovoltaic power generation not affect the smooth operation of the grid... With the continuous increase of solar penetration rate, it has brought challenges to the smooth operation of the power grid. Therefore, to make photovoltaic power generation not affect the smooth operation of the grid, accurate photovoltaic power prediction is required. And short-term forecasting is essential for the deployment of daily power generation plans. In this paper, A short-term photovoltaic power generation forecast method based on K-means++, grey relational analysis (GRA) and support vector regression (SVR) (Hybrid Kmeans-GRA-SVR, HKGSVR) was proposed. The historical power data was clustered through the multi-index K-means++ algorithm. And the similar days and the nearest neighbor similar day of the prediction day were selected by the GRA algorithm. Then, similar days and nearest neighbor similar days were used to train SVR to obtain an accurate photovoltaic power prediction model. Under ideal weather, the average values of MAE, RMSE, and R<sup>2</sup> were 0.8101 kW, 0.9608 kW, and 99.66%, respectively. The average computation time was 1.7487 s, which was significantly better than the SVR model. Thus, the demonstrated numerical results verify the effectiveness of the proposed model for short-term PV power prediction. 展开更多
关键词 Grey Relational Analysis K-Means++ Nearest Neighbor Similar Day Photovoltaic Power Support Vector Regression
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An Efficient Class of Estimators for the Finite Population Mean in Ranked Set Sampling
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作者 Lakhkar Khan Javid Shabbir 《Open Journal of Statistics》 2016年第3期426-435,共10页
In this paper, we propose a class of estimators for estimating the finite population mean of the study variable under Ranked Set Sampling (RSS) when population mean of the auxiliary variable is known. The bias and Mea... In this paper, we propose a class of estimators for estimating the finite population mean of the study variable under Ranked Set Sampling (RSS) when population mean of the auxiliary variable is known. The bias and Mean Squared Error (MSE) of the proposed class of estimators are obtained to first degree of approximation. It is identified that the proposed class of estimators is more efficient as compared to [1] estimator and several other estimators. A simulation study is carried out to judge the performances of the estimators. 展开更多
关键词 Ranked Set Sampling Auxiliary Variable BIAS Mean Squared Error Relative Efficiency
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Analysis of Length of Stay (LOS) Data from the Medical Records of Tertiary Care Hospital in Saudi Arabia for Five Diagnosis Related Groups: Application of Cox Prediction Model
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作者 Sara AL-Gahtani Mohamed M. Shoukri 《Open Journal of Statistics》 2021年第1期99-112,共14页
<strong>Background: </strong><span style="font-family:""><span style="font-family:Verdana;">One of the main objectives of hospital managements is to control the length ... <strong>Background: </strong><span style="font-family:""><span style="font-family:Verdana;">One of the main objectives of hospital managements is to control the length of stay (LOS). Successful control of LOS of inpatients will result in reduction in the cost of care, decrease in nosocomial infections, medication side effects, and better management of the limited number of available patients’ beds. The length of stay (LOS) is an important indicator of the efficiency of hospital management by improving the quality of treatment, and increased hospital profit with more efficient bed management. The purpose of this study was to model the distribution of LOS as a function of patient’s age, and the Diagnosis Related Groups (DRG), based on electronic medical records of a large tertiary care hospital. </span><b><span style="font-family:Verdana;">Materials and Methods: </span></b><span style="font-family:Verdana;">Information related to the research subjects were retrieved from a database of patients admitted to King Faisal Specialist Hospital and Research Center hospital in Riyadh, Saudi Arabia between January 2014 and December 2016. Subjects’ confidential information was masked from the investigators. The data analyses were reported visually, descriptively, and analytically using Cox proportional hazard regression model to predict the risk of long-stay when patients’ age and the DRG are considered as antecedent risk factors. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Predicting the risk of long stay depends significantly on the age at admission, and the DRG to which a patient belongs to. We demonstrated the validity of the Cox regression model for the available data as the proportionality assumption is shown to be satisfied. Two examples were presented to demonstrate the utility of the Cox model in this regard.</span></span> 展开更多
关键词 Diagnostic Related Groups K-Means Clustering In Hospital Length of Stay Cox Proportional Hazard Models Relative Risk Estimation
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