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Vee-tail conceptual design criteria for commercial transport aeroplanes

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Chinese Journal of Aeronautics 2019年第3期32卷 595-610页

作者： Alejandro SANCHEZ-CARMONA Cristina CUERNO-REJADO Faculty of Aerospace Engineering Department of Aircraft and Spacecraft Technical University of Madrid (Universidad Poltécnica de Madrid)

Vee-tail configuration is an unconventional tail configuration for commercial transport aviation, the use of which could suppose reductions on CO2 emissions. The conceptual design criteria have been selected inspired on the certification requirements established by the aviation regulation in force. They are static stability in cruise, control after Critical Engine Failure(CEF),control in crosswind landing, and trim in these three conditions. The study is carried out through a combination of semi-empirical techniques and Vortex-Lattice Methods(VLM) and thus this analyses the consequences of applying these criteria to a reference aeroplane substituting its conventional tail by a parametrised Vee-tail configuration. The Vee-tail is defined by four parameters:span, root chord, taper ratio and dihedral angle. The results of the study establish a relation between the parameters in order to accomplish the proposed conceptual design criteria. To sum up, minimum and maximum limits are obtained for dihedral angle depending on the combination of the rest of parameters. In addition, a design restriction to the yawing trailing-edge tail control is reached when the results are analysed, demonstrating that its minimum size must be between 60%and 80% of the half-span of the tail, depending on the Vee-tail geometry.

关键词： Commercial transport aeroplane conceptual aircraft design Tail design requirements Unconventional tail design Vee-tail

Extractive distillation: Advances in conceptual design, solvent selection,and separation strategies

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Chinese Journal of Chemical Engineering 2019年第6期27卷 1247-1256页

作者： Shirui Sun Liping Lü Ao Yang Shun'an Wei Weifeng Shen School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China School of Chemistry and Chemical Engineering Yangtze Normal UniversityChongqingFuling 408100China Collaborative Innovation Center for Green Development in Wuling Moutain Area Yangtze Normal UniversityChina

Extractive distillation(ED) is one of the most promising approaches for the separation of the azeotropic or closeboiling mixtures in the chemical industry. The purpose of this paper is to provide a broad overview of the recent development of key aspects in the ED process involving conceptual design, solvent selection, and separation strategies. To obtain the minimum entrainer feed flow rate and reflux ratio for the ED process, the conceptual design of azeotropic mixture separation based on a topological analysis via thermodynamic feasibility insights involving residue curve maps, univolatility lines, and unidistribution curves is presented. The method is applicable to arbitrary multicomponent mixtures and allows direct screening of design alternatives. The determination of a suitable solvent is one of the key steps to ensure an effective and economical ED process. Candidate entrainers can be obtained from heuristics or literature studies while computer aided molecular design(CAMD) has superiority in efficiency and reliability. To achieve optimized extractive distillation systems, a brief review of evaluation method for both entrainer design and selection through CAMD is presented. Extractive distillation can be operated either in continuous extractive distillation(CED) or batch extractive distillation(BED), and both modes have been well-studied depending on the advantages in flexibility and low capital costs. To improve the energy efficiency, several configurations and technological alternatives can be used for both CED and BED depending on strategies and main azeotropic feeds. The challenge and chance of the further ED development involving screening the best potential solvents and exploring the energy-intensive separation strategies are discussed aiming at promoting the industrial application of this environmentally friendly separation technique.

关键词： Extractive distillation Separation strategies Solvent selection conceptual design

conceptual Metaphor and Literary Discourse:A Study of the Implicit conceptual Metaphor in Somerset Maugham's Rain

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外国语 2016年第5期39卷 2-19页

作者： REN Shaozeng Zhejiang University Hangzhou 310058China

This paper looks into the implicit conceptual metaphor in the short story Rain by Somerset Maugham from a cognitive-functional perspective. The word "rain",with its unusual frequency of occurrence and used in a less common clause structure in the discourse,is obviously foregrounded. But rain is not what the story is about,it is about the protagonist,a missionary,Davidson by name and his relationship with a woman named Thompson. Rain is used symbolically as the source domain,but where is the target domain? The recurrence of "the rain",which forms a metaphoric chain,moves the narrative through its entire structure,beginning with Orientation,through 11 phases in Complication Actions until it reaches Resolution,which takes the form of Davidson's suicide. The ending comes as a surprise to the reader and forces him to look back and re-contextualize the story on the basis of a series of counter-expectancies and linguistic expressions so that he finds the relationship between Davidson and Thompson was not one between a preacher and a sinner,but one between a man and a woman. Linguistic analysis and cognitive analysis bring to light the fact that what made Davidson behave the way he did was not only his religious fanaticism but,more decisively,also his inner urge or desire,which turns out to be the target domain. The fascinating role metaphor and metonymy play in the unfolding of discourse makes it possible to establish the cross-domain mapping of knowledge about rain onto knowledge about desire,so the dominant conceptual metaphor,Desire Is Rain,finally takes shape. This is how the discourse realizes the conceptual metaphor. As the metaphor is implicit,it takes a lot of inferencing to see how the discourse realizes it as it unfolds,and how the metaphor shapes the meaning of the discourse as it gradually emerges. The target domain is implied in order to make the story stylistically unique and heighten the cognitive impact of the short story.

关键词： rain conceptual metaphor discourse linguistic analysis conceptual analysis

The conceptual Fetters of the Mind-Body Problem

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Frontiers of Philosophy in China 2019年第4期14卷 612-629页

作者： FEI Duoyi School of Humanities China University of Political Science and LawBeijing 100088China

The crux of our encounter with the mind-body problem originates from a predicament on the underlying ontological level-from the category of concepts,it seems that the form for grasping the subjective aspects of the mind is incommensurable with the one for understanding the objective level of the brain.This is reflected in the fact that empirical expression is restricted by language,that psychological events cannot be incorporated into strict laws,and that the subject has a path that,with his own mental state,others cannot share.In order to make progress in cracking the mind-body problem,this paper tries to abandon the assumption that“psychology”and“physics”are mutually exclusive and are incompatible ontological categories.The“mind”and“body”are considered as two interchangeable yet non-coexisting perspectives.Therefore,events in the body are represented as conceptions in the mind,and have an expressive correspondence with one another.Meanwhile,the approach for achieving such correspondence involves the entity itself^the ability of the organism to perform purposeful activities constitutes the source of its internal activities.Through the connection of life categories-or rather,the coupling of living beings and their worlds-the mind and body maintain mechanisms which can be jointly realized.

关键词： mind-body problem conceptual fetters perspective continuum

The Deaths of One conceptual Metaphor in Two Languages

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Frontiers of Philosophy in China 2019年第2期14卷 322-341页

作者： Callisto Searle School of Philosophy Renmin University of China Beijing 100872 China

This title refers to what I see as the state of synonymy between the word "husbandry" in English and the word se 嗇 in Chinese. There are points of striking similarity, not only in the meaning and usage of these two words, but also in the changes in their usage over time, and I have found a comparative study of the etymology of these two words to be mutually illuminating. The similarity and potential for mutual analysis between these two case studies speaks to the universality of metaphor in thought and its expression, as well as the influence of shared experiences, such as agricultural practices, on how we talk about ideas that are more abstract. In English, the idea of a general practice of husbandry derived from the idea of the husbandman or farmer in Late Medieval English (Cl3th onwards). A more abstracted sense of husbandry, understood as an attitude that may be applied to abstract and intangible objects is witnessed in Shakespeare's sonnets in the Cl6th. This sense of husbandry, the husbandry of intangible resources, is also precisely the sense that is developed by a small and specialised group of writers in China represented by texts dating from the pre-Qin period to the Eastern Jin dynasty, following a similar progression from agricultural to ever more metaphorical senses of the practice of husbandry. The similarity of the process through which these abstracted meanings developed from concrete usage in both cases makes the pair mutually illustrative as I hope to show in this paper.

关键词： Pre-Qin Masters' texts conceptual metaphors agriculture

On conceptual Model Specification and Verification

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Journal of Computer Science and Technology 1987年第1期2卷 35-50页

作者：龚振和 Institute of Soft are Academia Siniera The No egian Institute of Technology Trondheim Noruay

Four classes of conceptual models are classified:pure static,dynamic,temporal and full time perspec-tive models.This paper presents a temporal framework fur specifying and verifying a conceptual model.Aspecification consists of static and temporal constraints,and operation descriptions.Consistency checkingof the specification is described.A simple example is used to illustrate the features of the framework.

关键词： descriptions constraints illustrate classified conceptual specification formulae operations relaxation legal

PRELIMINARY STUDY ON THE FORMATION MECHANISM OF COUNTER WESTERN BOUNDARY UNDERCURRENTS BELOW THE THERMOCLINE——A conceptual MODEL

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Chinese Journal of Oceanology and Limnology 1999年第1期17卷 1-9页

作者：王凡胡敦欣

Based on a simple conceptual model of stratified ocean, the criterion of the geostrophic velocity inversion in and below the thermocline was derived as h ′·η′<0 and ρ 1|η′|≤Δρ| h ′|, meaning that the slopes of the thermocline( h ′) and the sea surface(η′) must be opposite to each other, and that h ′ must be strong enough to satisfy the latter inequality. The criterion was applied to discuss the features of the western boundary undercurrents, the counter undercurrents of the western boundary currents below the thermocline, and to discuss the dynamics of their formation finally resulting from the combination of the basin scale circulation and local geostrophic balance. The formation mechanism, multi core structure, and transport variations of the Mindanao Undercurrent and those of other undercurrents, such as the North Equatorial Undercurrent and the Kuroshio undercurrent, can be satisfactorily explained by the above results.

关键词： western boundary undercurrents formation mechanism geostrophic velocity inversion criterion conceptual model

Multiply Charged Anions,Maximum Charge Acceptance,and Higher Electron Affinities of Molecules,Superatoms,and Clusters

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物理化学学报 2018年第6期34卷 675-682页

作者： VON SZENTPáLY László Institut fur Theoretische Chemie Universitat Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany.

The addition of electrons to form gas-phase multiply charged anions(MCAs)normally requires sophisticated experiments or calculations.In this work,the factors stabilizing the MCAs,the maximum electron uptake of gas-phase molecules,X,and the electronic stability of MCAs X^(Q-),are discussed.The drawbacks encountered when applying computational and/or conceptual density functional theory(DFT)to MCAs are highlighted.We develop and test a different model based on the valence-state concept.As in DFT,the electronic energy,E(N,v_(ex)),is a continuous function of the average electron number,N,and the external potential,v_(ex),of the nuclei.The valence-state-parabola is a second-order polynomial that allows extending E(N,v_(ex))to dianions and higher MCAs.The model expresses the maximum electron acceptance,Q_(max),and the higher electron affinities,A_Q,as simple functions of the firstelectron affinity,A_1,and the ionization energy,I,of the"ancestor"system.Thus,the maximum electron acceptance is Q_(max,calc)=1+12A_1/7(I-A_1).The ground-state parabola model of the conceptual DFT yields approximately half of this value,and it is termed Q_(max,GS)=?+A_1/(I-A_1).A large variety of molecules are evaluated including fullerenes,metal clusters,super-pnictogens,super-halogens(OF_3),super-alkali species(OLi_3),and neutral or charged transition-metal complexes,AB_(m )L_n^(0/+/-).The calculated second electron affinity A_(2,calc)=A_1-(7/12)(I-A_1)is linearly correlated to the literature references A_(2,lit) with a correlation coefficient R=0.998.A_2 or A_3 values are predicted for further 24 species.The appearance sizes,n_(ap)^(3-),of triply charged anionic clusters and fullerenes are calculated in agreement with the literature.

关键词： Multiply charged negative ions Their appearance sizes Second electron affinity Third electronaffinity conceptual density-functional theory Valence-state parabola model of electronegativity

conceptual Density Functional Theory Study of the Chemical Reactivity Properties and Bioactivity Scores of the Leu-Enkephalin Opioid Peptide Neurotransmitter

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Computational Molecular Bioscience 2019年第1期9卷 13-26页

作者： Juan Frau Norma Flores-Holguín Daniel Glossman-Mitnik Departament de Química Universitat de les Illes Balears Palma de Mallorca Spain Laboratorio Virtual NANOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Chihuahua Mexico

The SMD solvation model (Solvation Model based on the Density) and eight density functionals, CAM-B3LYP, LC-ωPBE, M11, MN12SX, N12SX, ωB97, ωB97X, and ωB97XD, were assessed in link with the Def2TZVP basis set for the calculation of the structure of the Leu-Enkephalin Opioid Peptide Neurotransmitter as well as their molecular properties. Through the conceptual Density Functional Theory (CDFT), the entire chemical descriptors for the system were calculated. The active regions of the molecules necessary for electrophilic, nucleophilic and radical attacks were chosen through linking them with the corresponding Fukui functions. Furthermore, the prediction of the pKa value for the peptide is done with great accuracy as well as the ability of the studied molecule in acting as an efficient inhibitor of the formation of Advanced Glycation Endproducts (AGEs), which comprises of a useful knowledge for the development of drugs for preventing Alzheimer, Diabetes and Parkinson diseases. Lastly, the bioactivity scores for the studied peptides are predicted via various methodologies.

关键词： Leu-Enkephalin Opioid Neurotransmitters Computational Chemistry conceptual DFT Bioactivity Scores