06/08/2014

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Wooden Structures The calculation and design elements of wooden structures and buildings. Until recently, the calculation was made of wooden structures on the allowable stress. Under this method, the calculated stress in a wooden element of operating loads compared with the permitted, the latter is obtained by dividing the tensile strength on the safety factor. In this case the tensile strength was taken on the basis of routine laboratory tests on small wood samples. Influence of the duration of the load of wood defects and other factors on the strength of the wooden structures were estimated to be the safety factor, which had different meanings for the lax, compressed and curved wooden elements. This calculation method gives an indication of the wooden structures at the operational load, but did not give a correct idea of the wooden structures in the state close to destruction. The source of the method of allowable stress of a linear relationship between stress and strain are not applicable in practice for many materials, especially wood, even at low voltages. Ignoring the plastic properties of materials, lack of consideration of the actual conditions of the structure under load, the method of calculation of allowable stress, do not give a correct idea of the true margin of safety. As a result of extensive research carried out by Soviet scientists had solved the problem of calculating the wooden structures in engineering limit states. This new method calculation takes into account the effect of various circumstances on the strength of the wooden structure. In the method of limit analysis, in contrast to the method of allowable stress, safety factor is divided into a number of individual coefficients, which take into account the probable change in the load (overload factor n), a possible change in material strength (quality factor k) and the...
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Theory Of The Knowledge 1.Introduo the present work presents a summary on what author Johannes Hessen explains on the types of knowledge, and on the criterion of the truth. For Hessen, the direction of the philosophical knowledge does not only search to solve enigmas, but also to discover things very special. It is not something Common would like to discuss. Moreover, Hessen raises a quarrel on the theory of the knowledge to the light of the fenomenologia, therefore the knowledge is born of the relation between the citizen and the object. The citizen and the object remain separate, however assuring that the dualism of the citizen and the object belongs to the essence of the knowledge. The theory of the knowledge as it disciplines philosophical, and its place in the set of the philosophy, part of the definition of the essence of the philosophy. 2.Os types of knowledge 2,1 the problem of the intuition and its history To apprehend spiritual an object, that is, to know something consists of a multiplicity of acts. The conscience cognoscente must go up to around the object to understand it, and the same thing makes the researchers and the Metaphysical, similar to understand something, therefore conscience cognoscente is used to advantage of diversified mental operations. It is excellent to question if it exists, beyond the mediate knowledge, one immediate one, and if beyond the discursivo, it exists a intuitivo (for the look). It does not have doubts of that this knowledge exists, therefore everything that is given in them by the internal and external experiences, are apprehended by the mind of immediate form. However, when it is said of intuition, one is about a not-sensible intuition, that is, spiritual, that in turn cannot be denied. Until same the logical laws they are based on an intuition, therefore in...