共查询到20条相似文献,搜索用时 15 毫秒
1.
By the resultant theory, the E-characteristic polynomial of a real rectangular tensor is defined. It is proved that an E-singular value of a real rectangular tensor is always a root of the E-characteristic polynomial. The definition of the regularity of square tensors is generalized to the rectangular tensors, and in the regular case, a root of the E-characteristic polynomial of a special rectangular tensor is an E-singular value of the rectangular tensor. Moreover, the best rank-one approximation of a real partially symmetric rectangular tensor is investigated. 相似文献
2.
This paper deals with the problem of the instability regions of a free-free flexible jointed bipartite beam under the follower and transversal forces as a realistic simulation of a two-stage aerospace structure. The aim of this study is to analyze the effects of the characteristics of a flexible joint on the beam instability to use maximum bearable propulsion force. A parametric study is conducted to investigate the effects of the stiffness and the location of the joint on the critical follower force by the Ritz method and the Newmark method, then to research the vibrational properties of the structure. It has been shown that the nature of instability is quite unpredictable and dependent on the stiffness and the location of the joint. The increase of the follower force or the transversal force will increase the vibration of the model and consequently cause a destructive phenomenon in the control system of the aerospace structure. Furthermore, this paper introduces a new concept of the parametric approach to analyze the characteristics effects of a flexible two-stage aerospace structure joint design. 相似文献
3.
The dynamic response of an infinite beam placed on a Pasternak foundation when the system was subjected to a moving load was investigated. We used the double Fourier transform and its inversion to solve the formulations of the problem. A closed form analytic solution of the beam was obtained by the theorem of residues. We selected a numerical example to illustrate the dynamic response of the beam on Pasternak and Winkler foundations, respectively. We discuss the effect of the moving load velocity on the dynamic displacement response of the beam. The maximum deflection of the beam increases slightly with increased load velocity but increases significantly with reduced shear modulus of subgrade at a given velocity. The maximum deflection of a beam resting on a Pasternak foundation is much smaller than that of a beam on a Winkler foundation. 相似文献
4.
This study describes the application of a new product concurrent design methodologies in the context in the education of industrial design. The use of the sketch has been utilized many times as a tool of creative expression especially in the conceptual design stage, in an intuitive way and a little out of the context of the reality needs that the design should be attended. This methodology systematizes and guides the process of sketching by means of a conceptual model and a geometric model toward a feasible solution, complementing the role of the sketch in the phase of a product conceptual design. The model describes its operating principles, as well as the phases of implementation in the context of teaching the industrial design illustrated with projects carried out in the workshop of conceptual design of the University Technical College of Valencia and University of the Bio-Bio, Chile. Finally, we discuss the implementation of the systemic models, their relation with the optimisation of the sketching process in the conceptual design stage, and their implications in the educational context. 相似文献
5.
Theatre translation is one of the most neglected areas in the field of translation.Theatre is a special member of the literature family in that it doubles as a branch of the performing art.It follows that the aesthetic constitutions of a dramatic creation is a complex problem. It is the translator’s duty to grasp the artistic features of the literary creation and reproduce them in the version since the most important thing in a piece of literature is its artistic features. 相似文献
6.
One of the factors that affect the parameters of an underground cable is earth return path impedance. Pollaczek developed a formula for the case of one-layer (homogenous) earth. But in practice the earth is composed of several layers. In this study we develop a new formula for earth return path impedance in the case of a three-layer earth. To check the accuracy of the obtained results, a comparison has been made with the finite element method (FEM). A comparison between the results of the Pollaczek formula and results of the obtained formula for a three-layer earth has been made, showing that the use of the Pollaczek formula instead of the actual formula can cause serious errors. 相似文献
7.
American Dream refers to the belief of the majority of Americans.Through hard work,thrift,and determination,they can surely achieve a better life and live a comfortable life.Such an American Dream has a profound influence on several generations of Americans.American Dream has a close relationship with people’ s working life and cultural activities.Death of a Salesman is a typical play about the pursuit and the illusionary of the Dream follower.In Death of a Salesman,the American Dream is the main hero as well as Willy Loman’ s spiritual pillar.The pursuit,the realization,and the disillusionment of the American Dream develop with Willy and his family. 相似文献
8.
My Fair Lady is a movie about how a poor flower girl is turned into a graceful lady by changing the language she speaks with the help of a linguist.It demonstrates the great influence that language exerts on a person’s experience.This paper tries to analyze the movie from the perspective of sociolinguistics,especially the language variations caused by region,class,and gender difference,with the aim of helping the reader to have a better understanding of the movie and displaying the charm of language. 相似文献
9.
乔南 《中学数学教学参考》2008,(11)
Vectors may also be multiplied by a number. The productof the vector a by the number λ is defined as the vector a λ=λa, the absolute value of which is obtained by multiplying theabsolute value of the vector a by the absolute value of thenumber λ, i. e. |λa|=|λ||a|, the direction coinciding withthe direction of the vector a or being in the opposite sensedepending on whether λ>0 or λ<0. If λ=0 or a=0, then λ a 相似文献
10.
Among the modern rhetorical devices,metonymy and synecdoche are two important figures of speech,which are analogous to each other for both use the name of one thing for that of something else.That is to say,both of the rhetorical devices involve substitution.Thus the two concepts are confusing.Metonymy emphasizes on using the name of one thing for that of something else with which it is associated.Synecdoche is a figure of speech in which a part is used for a whole,an individual for a class,a material for a thing,or the reverse of any of these.By making a comparative study of these two through the connotation and category,the author summarizes that:they are two independent figures of speech. 相似文献
11.
Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medical-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hardening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show mechanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods. 相似文献
12.
INTRODUCTION An important problem in foundation engineeringis the determination of the rate of settlement of a raftfoundation placed on a deep clay layer. Gibson andMcNamee (1957), and McNamee and Gibson (1960a;1960b) considered the problem of normal uniformloading applied to the surface of a half-space andshowed that one-dimensional theory gives a markedunderestimate of the rate of settlement. This theorycorresponds to the case of a perfectly flexible footing.However, it is often… 相似文献
13.
杨正瓴 《天津大学学报(英文版)》2011,17(6):446-449
The more unambiguous statement of the P versus NP problem and the judgement of its hardness, are the key ways to find the full proof of the P versus NP problem. There are two sub-problems in the P versus NP problem. The first is the classifications of different mathematical problems (languages), and the second is the distinction between a non-deterministic Turing machine (NTM) and a deterministic Turing machine (DTM). The process of an NTM can be a power set of the corresponding DTM, which proves that the states of an NTM can be a power set of the corresponding DTM. If combining this viewpoint with Cantor’s theorem, it is shown that an NTM is not equipotent to a DTM. This means that "generating the power set P(A) of a set A" is a non-canonical example to support that P is not equal to NP. 相似文献
14.
The flow in a finite diverging channel opening into a large space and resembling the experimental prototype of Putkaradze and Vorobieff (2006) was numerically investigated. The effects of the Reynolds number, initial condition, intersection angle, length of the wedge edges, and the outer boundary condition were examined. The numerical results showed that the flow in the wedge undergoes a change from symmetrical flow to unsymmetrical flow with a weak backflow, then a vortical (circulation) flow and finally an unsteady jet flow as the Reynolds number is increased for an intersection angle of 32° and a wedge edge of length 30 times the width of the inlet slit. For the unsteady flow, the jet attached to one side of the wedge constantly loses stability and rolls up into a mushroom-shaped vortex-pair near the outlet of the wedge. As the intersection angle is increased to 50°, a stable jet flow is observed as a new regime between the vortex and unsteady regimes. Both the intersection angle and the wedge length have negative effects on the stability of the flow, although the effect of the wedge length on the critical Reynolds number for the symmetry-breaking instability is not pronounced. The outer boundary condition was found not to affect the flow patterns inside the wedge significantly. At a certain Re regime above the onset of symmetry-breaking instability, the flows evolve into steady state very slowly except for the initial stage in the case of decreasing flow flux. Two different solutions can be observed within the normal observation time for the experiment, providing a possible explanation for the hysteresis phenomenon in the experiment. 相似文献
15.
Lu Ling 《阜阳师范学院学报(社会科学版)》1999,(4)
One of the distinguishing featuros of English is its inflections, which experiencedchanges in the different periods. Old English is known as a language of full Inflections,Middle English as a language of leveling inflections and Modern English as a language oflost inflections. The history of English is in part the history of the gradual loss of the inflection system.Definition of inflectionInflection is the process of varying the form of a word to differentiate related meanings or uses. Fo… 相似文献
16.
Numerous experiments have shown that the water flow in fine-grained soils can obey an exponential relationship at small gradients and a linear relationship when the hydraulic gradient exceeds a certain limit. Based on the non-Darcian flow described by exponent and threshold gradient, the theory of 1D consolidation is modified in this paper to consider a linear variation in the vertical total stress with depth and the effect of ramp loading. The numerical solutions were derived in detail by the finite difference method for excess pore water pressure and the average degree of consolidation. Finally, the influence of various parameters on consolidation behavior was investigated. The results show that the rate of consolidation is reduced when non-Darcian flow described by exponent and threshold gradient is adopted in the theory of 1D consolidation. As well the distribution of vertical total stress has a great influence on the dissipation of excess pore water pressure, either for pervious top and pervious bottom (PTPB) or for pervious top and impervious bottom (PTIB). For the case of PTIB, the distribution of vertical total stress in a foundation has a great influence on the rate of consolidation; however, for the case of PTPB, the rate of consolidation is independent of the distribution of vertical total stress. The rate of consolidation is dependent on the ratio of the thickness of a soil layer to the equivalent head of the final average vertical total stress; the greater the value of this ratio, the slower the rate of consolidation. Finally, an increase in construction time reduces the consolidation rate of a foundation. Thus, consolidation behavior of 1D consolidation with non-Darcian flow has been thoroughly acquainted in this paper. 相似文献
17.
The Sphinx was a make-belive animal of long ago.It had the head of a person, the body of a lion,and the wings of a bird.The Sphinx lived near a city called Thebes. 相似文献
18.
Tracy Jiang 《英语大王(小学)》2003,(1)
Blue is the sky that finally appeared behind a winter of gray。Blue is the silhouette of a bird soaring high in the sky. Blue is the pedals of a newborn flower. Blue is the current of a rushing stream freed from the cold. Blue is the broken shells that revealed the world to twittering robins. 相似文献
19.
By using ABAQUS/Explicit, the dynamic process of an offshore wind turbine(OWT) stricken by a ship of 5000DWT in the front direction is simulated. The OWT is located on a large-scale prestressing bucket foundation constructed by an integrated installation technique. According to the simulation results, under the ship collision, a cer-tain range of plastic zone appears within a local area of arc transition structure of the bucket foundation, and the con-crete plastic zone is seriously damaged. As the stress level of OWT tower is relatively low, the OWT tower is less af-fected. A great inertial force is generated at the top of the OWT tower as the mass of nacelle and blades is up to 400 t. The displacement of the tower is in the opposite direction of the ship collision at the end of 1 s under the action of iner-tial force. There is only a minor damage in the ship bow. Most of the kinetic energy is transformed into the plastic dissipation and absorbed by the arc transition structure of bucket foundation. 相似文献
20.
Figen Eres 《美中教育评论》2010,7(4):94-100
The quality and the prevalence of education are the major indicators of the development of a society. It is a kind of human right to every person living in the society to be educated in a sufficient way. The education of the disabled people, a social reality in Turkey, is not sufficiently carried out. This paper aims at the education of the disabled people in Turkey. In order to mention about the education of the disabled people, this paper also mentions about the general characteristics of the disabled. The service of special education has not reached all the disabled, and the disabled and their families are not aware of the importance of the education. Only 90 thousand out of over one million disabled children receive the education. Disabled children continue their training in five groups: the sight impaired, the hearing impaired, the orthopedic impaired, the mentally impaired and children with long-term illness. Raising awareness is very important for all of the Turkish people. So a social education is necessary in order to deal with this problem. 相似文献