Archive for April, 2013


Welcome to all then: integral calculus. Integrate is the reciprocal process of the result, i.e., given a function f (x), looking for those functions F (x) that to be derived leading to f (x). It says, then F (x) is a primitive or antiderivada of f (x); said otherwise the primitives of f (x) is differentiable functions F (x) such that: F (x) = f (x). If a function f (x) is primitive, it has infinite primitives, differentiating them all in a constant. Indefinite integral is the set of the primitive infinite who can have a function. Do is represented by? f (x) dx. Do you read: integral of differential x x.? It is the sign of integration. f (x) is the integrating or function to be integrated.

DX is differential of x, and indicates what is the variable of the function to be integrated. C is the constant of integration and can take any real numerical value. If F (x) is an antiderivative of f (x) must be:? f (x) dx = F (x) + C to verify that the antiderivative of a function is correct enough with derive. Properties of the indefinite integral?do f (x) + g (x) dx =? f (x) dx +? g (x) dx immediate INTEGRALS of the derivation of elementary functions are deduced their corresponding immediate calls integrals. It is necessary to learn these results if you intend to be agile in the calculation of other less simple integrals.

1.?do f (x) + g (x) dx =? f (x) dx +? g (x) dx 2. do k f (x) dx = k? f (x) dx 2. If integrating by parts, we have a polynomial of degree n, we take it as u and the process is repeated n times. If we have an integral with only a logarithm or a bow, integrate by parts taking: v = 1.


A very good consultation on the part of a visitor to my Blog originated this article which I hope to many. Procedure for the calculation of the readjustment of the canon of lease. Today in Chile, almost no longer residential lease contracts that are expressed in dollars if not that, like corporate or commercial leases these are already working with our known UF. This phenomenon has occurred by the great economic stability Chile has grown through the years and increasingly have expanded deadlines for readjustments in lease contracts reaching even parameters do it once a year. Therefore, lately housing rental contracts are have been drafted in UF achieving a monthly adjustment without having to be constantly and every 3 months calculating the new value of monthly rental for a residential property.

The benefits are numerous both for the owner and the lessee, and more comfortable for the real estate agent who leads the administrations of these buildings. It is thus as each tenant to arrive the date of payment stipulated in the contract of lease only you must multiply the value of the barrel expressed in UF the UF value that day and ready, your new canon’s lease is up to date. This allows the lessee to constantly know the value of your lease and frees the owner be constantly bothered to calculate the new lease even though this does not exempt him revise that that calculation your tenant has succeeded it. It should be noted that the variation of the CPI can be negative or positive depending on market fluctuations that affect the value of the goods and services involved for the monthly calculation of economic index so at times the value of the barrel down and others will rise depending on whether the CPI is being positive or negative for a particular month. Case of leases written in pesos, reset can be quarterly, half-yearly or yearly basis as they agreed by the parties at the time of closing the deal.

Structural Analysis

Structural analysis consists in the verification of the resistance of the sections of a structure, which requires knowing the distribution of internal forces in the structure. The internal forces of a structure isostatic can be found with the equations of static equilibrium. In an indeterminate structure static equilibrium equations are not enough and must meet geometric conditions under load. The internal forces of a structure can be determined by means of elastic analysis or plastic overall analysis, although the latter serves only when certain conditions are satisfied. The internal forces are calculated using different methods, as you can disregard or not the effect of the deformation in the structure. In the first-order theory, calculations relate to the initial geometry of the structure (small deformations).

The forces acting on the bars vary not just with displacement. In the theory of second-order calculations refer to geometry deformed under load of the structure. The displacements of the structure and its effect on forces in the bars are not negligible. The theory of second order, more generally, is used for all cases without restrictions. If we apply the theory of first order, and structure materials satisfy Hooke’s law, we are in a case of linear calculation, where all movements vary linearly with the applied forces.

In this case, the superposition principle can be applied to tensions, deformations, internal forces and displacements due to different actions. The superposition principle says that displacement due to multiple loads acting simultaneously is equal to the sum of the displacements due to the action of each charge separately. This principle cannot be applied if the material stress-strain relationship is not linear, or if the structure (although the material obeys Hooke’s law) does not behave linearly due to geometry changes caused by the applied loads.

That Is The Web Usability

Web usability is simply the degree of ease with which users have to use all the features of a web site. The greater or lesser degree of usability impacts directly in the mean time visit to a site, the percentage of bounce out (visitors who come but a few seconds will be, and what is worse, never return), and the effectiveness of the call to actions (which serve to tell the users what are the things that you want actually to do the user on your site). It seems easy, but not so much. Web usability experts must possess knowledge of graphic design, aesthetics, and physiology of the human being. Visual patterns influence greatly the effectiveness of various elements of the site. It follows, then, that the Visual elements of the site have much to do with usability. One of the most problematic issues in web usability are the forms. Many times it happens that once is to capture the attention and interest of the visitor, it seems that the webmaster or the owners of the sites it gives them a kind of anxiety to take full advantage of this contact.

It is not wrong to do so, but we really need to know the nationality of the visitors, or lives in the neighborhood? Mandatory fields are, in general, responsible for much of the bounce out rates. Many times users do not want to disclose certain sensitive information, especially the financial, or, on occasions, the phone or home address. If you actually need to collect these data, you can do so at later stages of interaction. Please, unless it is really necessary, do not use Captcha! It is preferable to use a question like what is the month preceding September?, or a mathematical calculation. Let’s use common sense. Let’s imagine that you invited its users to download a demo, with what reason would so important in this situation to control spam? The inclusion of links and sidebars tend to significantly increase web usability, as well as the breadcrumb, that path of links that usually appear at the top of a site, It allows us to go back a step, or initiate the process again without using the browser back button. Arrive at a more or less permanent site design is a process, with movements forward, but, inevitably, steps backward. Try to find a style for your site, with your look and feel special, but make sure that all users wishing to do so can make use of the same, including those which already combed gray, and whose visual acuity begins to surrender. If you liked this post and want to place it on your site, you can do so smoothly, provided you cite as a source to original author and source of the article.