Growing Staff Presentation as Human Resource Management Consultan PowerPoint

Growing Staff as Human Resource Management Consultan - PowerPoint Presentation Example has undertaken for the purpose of making sure that its top management have the right requisite skills that will translate in the production of the required results. This in essence will lead to the achievement of the goals and objectives that have been put in place by the firm. The first among this is the building of skills in the leaders. The dynamic nature of business operations calls for individuals who are in a position to adapt to the various situations that present themselves in the business world. This is not forgetting the Human Resource Issue. For this reason, the individuals should be more adaptive for the purpose of boosting their performance and overall score in the work environment. It is of the essence to note that the organization has various individuals working therein. For this reason, the propositions may not be taken in well by all the parties involved. To some, this may be taken as a way of locking out some individuals, especially those who are not well qualified for certain positions. However, it is of the essence to note that the training, which is undertaken, is for the benefit of all the individuals in the organization when it comes to their general performance. Fashion design is purely artistic and as such, it is the designer and the assistants who determine how far a brand goes. Nonetheless, technology has changed all fronts of our daily lives dramatically; adding innovativeness to what we have always done hence easing our daily loads. The current workforce of Michael Kors Fashion House is large. With 372 workers for a company of its size, it is a record. The large workforce’s output is limited in comparison with what they should be producing. The gap between the workers and the target output is in their inconsistency due to poor work ethics and lack of adaptation of technology. If the company can invest in its workers, it sure will invest in its future. The possibility of the company producing double the much it does today in the

Wings of desire. Analysis of the Film Essay Example | Topics and Well Written Essays - 750 words

Wings of desire. Analysis of the Film - Essay Example Each and every city has a history. Human nature is characterized by dynamism and this is reflected on all what surrounds man. Berlin is a no such exception city as it can be read from two dimensions, i.e. visible and invisible. In the film, â€Å"Wings of Desire†, a number of features, which will be discussed later in this paper, prove to be imminent. Art being a reflection of the society, â€Å"Wings of Desire† is a reflection of the life style and depiction of the Berlin city. This city is interesting and has had a capability of combining all the factors that mould a modern city having elements of the past that shape its future. Whether this city is purely real, hyperreal or surreal or may be purely an invisible depends on the spatial history it presents and the different landmarks which show themselves. The wings of desire present two dimensions of the Berlin. Visible Dimension Berlin City can be viewed from the visible dimension. When you visit this city as the film shows you are in a position to see the wall that separates the East and the West of Germany. For many years, this wall has been a real depiction of where this city has come from. It harbors a rich history and this film presents the wall as a site for memory. The wall goes round the City. When people saw the wall, because it was brought down after the shooting of â€Å"wings of desire†, they would have a recap of what happened to their country leading to the separation of East and West Germany. The essence of reality is more felt when the meditation of the history with which this wall carries is effected by first sight this historic feature. For this reason, this wall acting like a landmark feature that was passed on from generation to generation then the sets Berlin city to have the characteristics of realism. A real city has its history attached to the available landmarks that might be manmade or natural and this is something which Berlin clearly presents through the wall. Berlin City has features that tend to embrace idealism. This is a visible dimension whereby subliminal regime is created. Berlin City has special functions for the bridges whereby symbolism and rich history is embedded on them. The bridges link and act as frontiers. It is this feature that makes them very ideal for writing history on them that when people pass by, they can have a look at it. Often the streets, as depicted in this film, have few people with stereotypes of metropolis taking a lead. In addition, the houses together with the streets happen to be anonymous and this presents a rather hard to puzzle situation. The canals clearly confirm that this city is a real metropolitan centre giving life to the surreal ideologies. The ideologies of hyperreal cities bring in the power of imaginations and through the imaginations decisions can be made. A perspective is drawn and Berlin has created search a setting for the world to see. Though luftschutzbunker is a standing remnant of th e effects of World War II, it offers a moment of reflection. A thought of today are imaginatively shifted to try to figure out how yesterday would have been if it were today. This can be described as fiction, something that can only happen in movies and films and this is what basically entails hyperreal cities. The library preserves information. As a visual phenomenon of the Berlin City, it has been distinguished for memory purposes. Not that the Homer does not have the information he really ought to know but rather chooses to opt for memory so as to exploit the excellence which comes along. As depicted, in the film, the library is the place believed to offer angels’ gathering point and excellence is much emphasized. Memory refreshment is the key goal. Invisible Dimension For Berlin, features of invisible dimension are eminent. History has proven that, whatever is seen can communicate more if a little of thoughts are engaged. This is the situation which confronts anybody whol e

Macbeth coursework Essay Example for Free

Macbeth coursework Essay We know that lady Macbeth is not calm in the beginning of act 2 scene 2 because of all the factors used to create tension and an eerie surrounding, these are it is dark, some one has just gone to murder the king and the owl shrieking. She will also be on edge and continually watching her back, this will be because Macbeth has just gone to murder the king, and if it goes wrong everything points to them and they will be executed for treason. To calm her down she has a drink, that which hath made them drunk hath made me bold this shows she has had a drink to make her courageous. To add even more tension to this already tense scene the speech speed dramatically increases, When? Now. As I descended? You can tell the speed increases allot because they dont say more than three words to each other in this banter at this point in the scene. When the two actors playing this scene are acting they should be moving around in synchronised circles around the stage and express their speech in hand movements. After this they move onto a different subject, Donaldbain, the kings son. The whole of this scene should be spoken not to loud but not to quiet because it is so early in the morning that it is dark, and everyone in the castle apart from them two is asleep. Macbeth then starts to tell Lady Macbeth that he heard the two guards and other voices praying and talking to him, Theres one did laugh ins sleep, and one cried murder! he is telling Lady Macbeth about his hearings in this quote. Lady Macbeth believes him but does not want him to develop on these thoughts and move on, consider it not so deeply. She is now telling him to move on to another subject and carry on as normal. She could be a bit worried about her husband Macbeth, these deeds must not be thought she is worried that he is dwelling on this subject too much for his and her own good, it will make us mad. This sentence is very ironic because in the later stages of the play it comes true, this comes true because lady Macbeth goes around washing her hands thinking there is blood on them but there actually isnt. This ends in her committing suicide. She could also be trying to comfort him, What do you mean? she could be trying to get all of his bad feelings out of him and out in the open so she can deal with him. This could also lead to it being easier for her to manipulate him by exploiting his weaknesses. The stronger character in this scene and the whole time she is in the play is Lady Macbeth in the way she controls her whole surroundings to the way she wants, these deeds must not be thought in this part of the play she is in controlling she is literally telling him what to think. There is a great warrior who has killed many in battle is putty in his wives hands, she can mould him into feeling and doing what she wants. Macbeth starts to show a little amount of backbone in the middle of the scene, Ill go no more. This is when he confronts her and tells her he wont do anymore when she tells him to put the daggers back and smear the blood on the guards. Earlier at the beginning of the scene when Macbeth returns from the murder of the king he brings back two crucial pieces of evidence that links them to the murder. The plan was to kill the king with the guards daggers and return the daggers after smearing the blood on the two guards to frame them. He does all of this apart from the returning the daggers. When Lady Macbeth realises this she is furious,Infirm of purpose! She raised her voice severely, to prove how angry she is. She is saying to him that he cant do the simple job he was told to do. So because of this fault it looks like the guards are innocent and they wanted to frame them. When Lady Macbeth goes to return the daggers this shows us she is not a normal women in accordance to those times, Ill gild the faces of the grooms withal this shows us she is not afraid to stare In the face of death and smear the faces of the guards which she has manipulated her husband to do. This is very strange because when this play was made the country was a very Christian and to murder a man in cold blood was a very serious offence let alone blame the murder on his own guards. Lady Macbeth is not a normal as we know because earlier in the play when we first see her in act 1 scene 5 she calls upon evil spirits to make her more of a man than a woman. When Lady Macbeth returns from smearing the blood on the guards she says, A little water clears us of this deed. She is basically saying that all it needs is a little bit of water to clean their hands then they are in the clear of the murder. This sentence is also ironic because when Lady Macbeth gets mentally ill in the later stages of the play she thinks her hands have blood on them so she continually washes them thinking the blood is still there even though there is none there. The way that Lady Macbeth is portrayed throughout the whole play from Act 1 scene 5 till she commits suicide is she is an opportunist; she sees the opportunity that Macbeth can become king so she pushes him and manipulates him to think he is the rightful king. She will also do anything to be crowned queen alongside him. She is also shown as very devious and a manipulator this is shown as she controls the best Scottish warrior is like a dog and she is the owner she tells him what to do and he does it, or a puppet master and the puppet. She also manipulates the noblest warrior to kill in cold blood. She is shown most of the way through the play as the more prominent and powerful character of all the characters in the play. I think that Shakespeare tried and succeed in personifying the devil in Lady Macbeth in the way she controls her environment to her advantage. What I thought of Lady Macbeth in the first time we see her when she reads the letter from Macbeth was that she was an elegant woman nothing like she turns out to be. But after she hears the prophecy about Macbeth becoming the king it is like an on/off switch to turn on or off the evilness inside of her. She believes, He is too full of the milk of human kindness. Meaning he is too kind to do any of the deeds he has done so far. Straight away she is scheming and wanted him to hurry home so she can, Pour my spirits in thine ear. Basically she wants to poison his mind.

An operational amplifier

An operational amplifier Introduction: Anoperational amplifier, which is often called anop-amp, is aDC-coupledhigh-gainelectronic voltageamplifierwith a differential input and, usually, a single-ended output.An op-amp produces an output voltage that is typically millions of times larger than the voltagedifferencebetween its input terminals. Typically uses of the operational amplifier are to provide voltage amplitude changes (amplitude and polarity), oscillators, filter circuits, and many types of instrumentation circuits. An op-amp contains a number of differential amplifier stages to achieve a very high voltage gain. Typically the op-amps very large gain is controlled bynegative feedback, which largely determines the magnitude of its output voltage gain in amplifier applications, or thetransfer functionrequired. Without negative feedback, and possibly withpositive feedbackforregeneration, an op-amp essentially acts as acomparator. High inputimpedanceat the input terminals and low output impedance at the output terminals (ideally zero) are important typical characteristics. Op-amps are among the most widely used electronic devices today, being used in a vast array of consumer, industrial, and scientific devices. Many standard IC op-amps cost only a few cents in moderate production volume; however some integrated or hybrid operational amplifiers with special performance specifications may cost over $100 US in small quantities. Op-amps sometimes come in the form of macroscopic components, or asintegrated circuitcells; patterns that can be reprinted several times on one chip as part of a more complex device. The op-amp is one type ofdifferential amplifier. Other types of differential amplifier include thefully differential amplifier(similar to the op-amp, but with two outputs), theinstrumentation amplifier(usually built from three op-amps), theisolation amplifier(similar to the instrumentation amplifier, but with tolerance to common-mode voltages that would destroy an ordinary op-amp), andnegative feedback amplifier(usually built from one or more op-amps and a resistive feedback network). An Amplifier is made of: A Gain Block (ideally possessing infinite gain) Feedback A Network that sets the amount of feedback (e.g. resistors) The circuit symbol for an op-amp is shown to the right, where: The power supply pins (V_{text{S}!+}andV_{text{S}!-}) can be labelled in different ways). Despite different labelling, the function remains the same to provide additional power for amplification of signal. Often these pins are left out of the diagram for clarity, and the power configuration is described or assumed from the circuit. Op amps are versatile ICs that can perform a variety of mathematical functions. For this reason, they are the building blocks of many signal processing circuits. They have almost infinite gain, high input impedance, and low output impedance. Because of this, there is no current drawn at either input, and the voltage at both inputs must be equal (they are often drawn with a short connecting them) Op amps have two inputs, an inverting (-) and non inverting (+). A positive voltage source and negative voltage source or ground are connected directly to the op amp, although these are rarely shown on circuit diagrams. There is a single output, which is almost always connected to the inverting input with a feedback loop. Ideal Op Amps: There are three rules for analyzing op amp circuits. In addition to KVL and KCL, any op amp circuit should be solvable with these rules. Infinite input impedance. No current is drawn so: Infinite gain. This means that the input voltages must be equal. Zero output impedance. This means that output voltage does not depend on the output current. Real Op Amps: Ideal op amps are modelled with infinite gain and infinite impedance. While real op amps have high gain and low impedance, they are not infinite. This limiting factor can affect the performance of the circuit, so it should be considered. Another limitation of real op amps is voltage gain. Instead of being infinite, the maximum output voltage is about 1.4 V lower than the supply voltage (this is due to diode drops in the op amp). Ideal behaviour is not an accurate modelling technique when square waves are used. For this type of input, the voltage changes infinitely fast as it jumps from the high to the low parts of the wave. Op amps cant change instantaneously, there is a slight slope produced in the output. This can be measured by the slew rate (with is the change in voltage over the change in time). Rise time is another parameter used to calculate how quickly an op amp can adjust. The amount of time it takes the voltage to change from 10% to 90% of the desired value is the rise time. For application with square wave input, these two factors can affect the response of your circuit. Connecting an Op Amp: Op amps with Dual in Line Packages should be connected to a breadboard as shown here. The notch is at the top of the op-amp, with pins counted counter clockwise from the upper left corner. Operation: The amplifiers differential inputs consist of V_{!+}input and aV_{!-}input, and ideally the op-amp amplifies only the difference in voltage between the two, which is called thedifferential input voltage. The output voltage of the op-amp is given by the equation, WhereV_{!+}the voltage at the non-inverting terminal is,V_{!-}is the voltage at the inverting terminal andGopen-loopis theopen-loopgain of the amplifier. (The term open-loop refers to the absence of a feedback loop from the output to the input.) Op-amp with inverting input grounded through a resistor; input at the non-inverting input, and no feedback With no negative feedback, the op-amp acts as a switch. The inverting input is held at ground (0 V) by the resistor, so if the Vinapplied to the non-inverting input is positive, the output will be maximum positive, and if Vinis negative, the output will be maximum negative. Since there is no feedback from the output to either input, this is anopen loopcircuit. The circuits gain is just the Gopen-loopof the op-amp. Standard two-resistor non-inverting amplifier circuit The magnitude ofGopen-loopis typically very large-seldom less than a million-and therefore even a quite small difference betweenV_{!+}andV_{!-}(a few microvolts or less) will result in amplifier saturation, where the output voltage goes to either the extreme maximum or minimum end of its range, which is set approximately by the power supply voltages.Finleys lawstates that When the inverting and non-inverting inputs of an op-amp are not equal, its output is in saturation. Additionally, the precise magnitude ofGopen-loopis not well controlled by the manufacturing process, and so it is impractical to use an operational amplifier as a stand-alonedifferential amplifier. If linear operation is desired,negative feedbackmust be used, usually achieved by applying a portion of the output voltage to the inverting input. The feedback enables the output of the amplifier to keep the inputs at or near the same voltage so that saturation does not occur. Another benefit is that if much negative feedb ack is used, the circuits overall gain and other parameters become determined more by the feedback network than by the op-amp itself. If the feedback network is made of components with relatively constant, predictable, values such as resistors, capacitors and inductors, the unpredictability and inconstancy of the op-amps parameters (typical of semiconductor devices) do not seriously affect the circuits performance. If no negative feedback is used, the op-amp functions as a switch or comparator. Positive feedback may be used to introducehysteresisor oscillation. Returning to a consideration of linear (negative feedback) operation, the high open-loop gain and low input leakage current of the op-amp imply two golden rules that are highly useful in analysing linear op-amp circuits. Golden rules of op-amp negative feedback Ifthere is negative feedback andifthe output is not saturated, both inputs are at the same voltage; no current flows in or out of either input. These rules are true of the ideal op-amp and for practical purposes are true of real op-amps unless very high-speed or high-precision performance is being contemplated (in which case account must be taken of things such as input capacitance, input bias currents and voltages, finite speed, and otherop-amp imperfections, discussed in a later section.) As a consequence of the first rule, theinput impedanceof the two inputs will be nearly infinite. That is, even if the open-loop impedance between the two inputs is low, the closed-loop input impedance will be high because the inputs will be held at nearly the same voltage. This impedance is considered as infinite for an ideal opamp and is about onemegaohmin practice. Ideal and real op-amps: An equivalent circuit of an operational amplifier that models some resistive non-ideal parameters. An ideal op-amp is usually considered to have the following properties, and they are considered to hold for all input voltages: Infiniteopen-loop gain(when doing theoretical analysis, alimitmay be taken as open loop gainGgoes to infinity) Infinite voltage range available at the output (vout) (in practice the voltages available from the output are limited by the supply voltagesV_{text{S}!+}andV_{text{S}!-}) Infinitebandwidth(i.e., the frequency magnitude response is considered to be flat everywhere with zerophase shift). Infiniteinput impedance(so, in the diagram,R_{text{in}} = infty, and zero current flows fromv_{!+}tov_{!-}) Zero input current (i.e., there is assumed to be noleakageorbiascurrent into the device) Zeroinput offset voltage(i.e., when the input terminals are shorted so thatv_{!+}=v_{!-}, the output is avirtual groundor vout= 0). Infiniteslew rate(i.e., the rate of change of the output voltage is unbounded) and power bandwidth (full output voltage and current available at all frequencies). Zerooutput impedance(i.e.,Rout= 0, so that output voltage does not vary with output current) Zeronoise InfiniteCommon-mode rejection ratio(CMRR) InfinitePower supply rejection ratiofor both power supply rails. In practice, none of these ideals can be realized, and various shortcomings and compromises have to be accepted. Depending on the parameters of interest, a real op-amp may be modelled to take account of some of the non-infinite or non-zero parameters using equivalent resistors and capacitors in the op-amp model. The designer can then include the effects of these undesirable, but real, effects into the overall performance of the final circuit. Some parameters may turn out to havenegligibleeffect on the final design while others represent actual limitations of the final performance that must be evaluated. History: 1941: First (vacuum tube) op-amp An op-amp, defined as a general-purpose, DC-coupled, high gain, inverting feedbackamplifier, is first found in US Patent 2,401,779 Summing Amplifier filed by Karl D. Swartzel Jr. of Bell labs in 1941. This design used threevacuum tubesto achieve a gain of 90dB and operated on voltage rails of  ±350V. It had a single inverting input rather than differential inverting and non-inverting inputs, as are common in todays op-amps. ThroughoutWorld War II, Swartzels design proved its value by being liberally used in the M9artillery directordesigned at Bell Labs. This artillery director worked with the SCR584radarsystem to achieve extraordinary hit rates (near 90%) that would not have been possible otherwise. 1947: First op-amp with an explicit non-inverting input In 1947, the operational amplifier was first formally defined and named in a paper by Professor John R. Ragazzini of Columbia University. In this same paper a footnote mentioned an op-amp design by a student that would turn out to be quite significant. This op-amp, designed by Loebe Julie, was superior in a variety of ways. It had two major innovations. Its input stage used a long-tailedtriode pair with loads matched to reducedriftin the output and, far more importantly, it was the first op-amp design to have two inputs (one inverting, the other non-inverting). The differential input made a whole range of new functionality possible, but it would not be used for a long time due to the rise of the chopper-stabilized amplifier. 1949: First chopper-stabilized op-amp In 1949, Edwin A. Goldberg designed achopper-stabilized op-amp.This set-up uses a normal op-amp with an additionalACamplifier that goes alongside the op-amp. The chopper gets an AC signal fromDCby switching between the DC voltage and ground at a fast rate (60Hz or 400Hz). This signal is then amplified, rectified, filtered and fed into the op-amps non-inverting input. This vastly improved the gain of the op-amp while significantly reducing the output drift and DC offset. Unfortunately, any design that used a chopper couldnt use their non-inverting input for any other purpose. Nevertheless, the much improved characteristics of the chopper-stabilized op-amp made it the dominant way to use op-amps. Techniques that used the non-inverting input regularly would not be very popular until the 1960s when op-ampICsstarted to show up in the field. In 1953, vacuum tube op-amps became commercially available with the release of the model K2-W from George A. Philbrick Researches, Incorporated. The designation on the devices shown, GAP/R, is a contraction for the complete company name. Two nine-pin 12AX7 vacuum tubes were mounted in an octal package and had a model K2-P chopper add-on available that would effectively use up the non-inverting input. This op-amp was based on a descendant of Loebe Julies 1947 design and, along with its successors, would start the widespread use of op-amps in industry. 1961: First discrete IC op-amps With the birth of thetransistorin 1947, and the silicon transistor in 1954, the concept of ICs became a reality. The introduction of theplanar processin 1959 made transistors and ICs stable enough to be commercially useful. By 1961, solid-state, discrete op-amps were being produced. These op-amps were effectively small circuit boards with packages such as edge-connectors. They usually had hand-selected resistors in order to improve things such as voltage offset and drift. The P45 (1961) had a gain of 94dB and ran on  ±15V rails. It was intended to deal with signals in the range of  ±10V. 1962: First op-amps in potted modules By 1962, several companies were producing modular potted packages that could be plugged intoprinted circuit boards. These packages were crucially important as they made the operational amplifier into a singleblack boxwhich could be easily treated as a component in a larger circuit. 1963: First monolithic IC op-amp In 1963, the first monolithic IC op-amp, the  µA702 designed byBob Widlarat Fairchild Semiconductor, was released. MonolithicICsconsist of a single chip as opposed to a chip and discrete parts (a discrete IC) or multiple chips bonded and connected on a circuit board (a hybrid IC). Almost all modern op-amps are monolithic ICs; however, this first IC did not meet with much success. Issues such as an uneven supply voltage, low gain and a small dynamic range held off the dominance of monolithic op-amps until 1965 when the  µA709 was released. 1966: First varactor bridge op-amps Since the 741, there have been many different directions taken in op-amp design.Varactorbridge op-amps started to be produced in the late 1960s; they were designed to have extremely small input current and are still amongst the best op-amps available in terms of common-mode rejection with the ability to correctly deal with hundreds of volts at their inputs. 1968: Release of the  µA741 The popularity of monolithic op-amps was further improved upon the release of the LM101 in 1967, which solved a variety of issues, and the subsequent release of the  µA741 in 1968. The  µA741 was extremely similar to the LM101 except that Fairchilds facilities allowed them to include a 30pF compensation capacitor inside the chip instead of requiring external compensation. This simple difference has made the 741thecanonical op-amp and many modern amps base their pin out on the 741s.The  µA741 is still in production, and has become ubiquitous in electronics-many manufacturers produce a version of this classic chip, recognizable by part numbers containing741. 1970: First high-speed, low-input current FET design In the 1970s high speed, low-input current designs started to be made by usingFETs. These would be largely replaced by op-amps made withMOSFETsin the 1980s. During the 1970s single sided supply op-amps also became available. 1972: Single sided supply op-amps being produced A single sided supply op-amp is one where the input and output voltages can be as low as the negative power supply voltage instead of needing to be at least two volts above it. The result is that it can operate in many applications with the negative supply pin on the op-amp being connected to the signal ground, thus eliminating the need for a separate negative power supply. The LM324 (released in 1972) was one such op-amp that came in a quad package (four separate op-amps in one package) and became an industry standard. In addition to packaging multiple op-amps in a single package, the 1970s also saw the birth of op-amps in hybrid packages. These op-amps were generally improved versions of existing monolithic op-amps. As the properties of monolithic op-amps improved, the more complex hybrid ICs were quickly relegated to systems that are required to have extremely long service lives or other specialty systems. Recent trends Recently supply voltages in analog circuits have decreased (as they have in digital logic) and low-voltage op-amps have been introduced reflecting this. Supplies of  ±5V and increasingly 5V are common. To maximize the signal range modern op-amps commonly have rail-to-rail inputs (the input signals can range from the lowest supply voltage to the highest) and sometimes rail-to-rail outputs. A very typical commercial IC op amp circuit is the 741. This IC has been available for many years, and a number of variations have been developed to help minimize the errors inherent in its construction and operation. Nevertheless, the analysis we will perform here using the 741 will apply to any other IC op amp, if you take into account the actual parameters of the device you are actually using. Therefore, we will use the 741 as our example IC op amp. A differential amplifier connected as an op amp. To the right is a circuit using the 741 op amp IC, with the input and feedback resistors that are required for this circuit to operate properly in an analog computer. Note that there are actually two inputs to the amplifier, designated + and - in the figure. This is because the 741, like all IC op amps of this type, is in fact a differential amplifier. Thus, the output voltage is determined by thedifferencebetween the two input voltages. The +, or non-inverting input, is grounded through a resistor as shown. Thus, its input voltage is always zero. The -, or inverting input, is the one that is actively used. Thus, we establish that the inverting input, which is also the junction of the input and feedback resistors, must operate as a virtual ground in order to keep the output voltage within bounds. So far, so good, but what about the actual voltage gain? It cant possibly be infinite, and if it isnt infinite, there must be some non-zero input voltage to produce a non-zero output voltage. In fact, the typical open-loop voltage gain for the 741 is 200,000. This does not mean that every such device has a gain of 200,000, however. What is guaranteed is that the commercial version (the 741C) will have a minimum gain of 20,000. The military version is more stringently selected, and will have a minimum voltage gain of 50,000. For the 741C, then, with a maximum output voltage of  ±10 volts, the maximum input voltage required at the inverting input can never be more than  ±10/20,000 =  ±0.0005 volt, or 0.5 milli volts. Typical measurement accuracy uses three significant digits, so we would measure voltages from 0.00 volts to  ±10.00 volts. The maximum input voltage is more than an order of magnitude smaller than this, and hence is insignificant in a typical analog computer. But what about input bias current? Surely the IC requires at leastsomesmall amount of input current? Well, yes, it does. The 741C requires a typical input bias current of 80 nA (thats nano Amperes, where 1nA=10-9A). The maximum input bias current for the 741C is 500nA, or 0.5 µA. So how do we use this information to minimize the errors it could cause into insignificance? Well, lets consider the resistance that would be required for this current to cause a significant voltage drop. If we keep the voltage error small enough, we can ignore it as immeasurable. This means we must keep the values of Rinand Rfas small as possible, consistent with proper operation of the circuit. At the same time, we cannot make them too small, or the op amp itself will be overloaded. For proper operation, the total load resistance at the 741 output should not be smaller than 2000 ohms, or 2k. This amounts to a maximum output current of 5 mA at 10 volts output. This means that the output resistance of the op amp is not the desired zero ohms. However, as long as you dont draw too much current from the output, the use of heavy negative feedback has an added benefit: It makes the op amp behaveas ifit had zero output resistance. That is, any internal resistance will simply mean that the op amp must produce an internal voltage enough higher than the calculated value so that the final output voltage will be the calculated value. So what if we make our input and feedback resistors about 10k each? Then the current demand on the output is only 1 mA at 10 volts, leaving plenty of capacity for additional inputs. And the voltage caused by the input bias current wont exceed 10,000-0.5-10-6=0.005volt. This is half of the least significant digit of our measurement capability, which is not as good as we would like, but will do. Also, this is the absolute worst-case situation; most practical applications wont see an error this big. In addition, the input bias current applies equally to both inputs. This is the reason for the resistor connecting the + input to ground. If this resistor is close in value to the parallel combination of Rin and Rf, the same voltage error will be generated at the two inputs, and will therefore be cancelled out, or very nearly. Thus, we can relegate this problem to true insignificance by means of correct circuit design and careful choice of component values. The 741 does also have two error characteristics, calledinput offset voltageandinput offset current, which define the inherent errors which may exist between the two inputs to the IC. However, the 741 also has the means for balancing these variations out, so the actual errors are minimized or eliminated, thus once again removing them from significance. A problem with any op amp is a limited frequency response. The higher the gain of the complete circuit, the lower the working frequency response. This is one reason an overall gain of 20 is a practical limit. (Another reason is that the input and feedback resistors become too different from each other.) Also, the standard 741 has aslew rateof 0.5v/ µs. This means that the output voltage cannot change any faster than this. The newer generation of op amps, such as the 741S, have a slew rate more like 5v/ µs, and hence can operate over the entire audio range of frequencies without serious problems. Classification of Operational Amplifier: Op-amps may be classified by their construction: discrete (built from individualtransistorsortubes/valves) IC (fabricated in anIntegrated circuit) most common hybrid IC op-amps may be classified in many ways, including: Military, Industrial, or Commercial grade (for example: the LM301 is the commercial grade version of the LM101, the LM201 is the industrial version). This may defineoperating temperatureranges and other environmental or quality factors. Classification by package type may also affect environmental hardiness, as well as manufacturing options;DIP, and other through-hole packages are tending to be replaced bySurface-mount devices. Classification by internal compensation: op-amps may suffer from high frequencyinstabilityin somenegative feedbackcircuits unless a small compensation capacitor modifies the phase- and frequency- responses; op-amps with capacitor built in are termedcompensated, or perhaps compensated forclosed-loopgains down to (say) 5, others: uncompensated. Single, dual and quad versions of many commercial op-amp IC are available, meaning 1, 2 or 4 operational amplifiers are included in the same package. Rail-to-rail input (and/or output) op-amps can work with input (and/or output) signals very close to the power supply rails. CMOSop-amps (such as the CA3140E) provide extremely high input resistances, higher thanJFET-input op-amps, which are normally higher thanbipolar-input op-amps. Other varieties of op-amp include programmable op-amps (simply meaning the quiescent current, gain, and bandwidth and so on can be adjusted slightly by an external resistor). Manufacturers often tabulate their op-amps according to purpose, such as low-noise pre-amplifiers, wide bandwidth amplifiers, and so on. Single-Ended Inputs With single-ended inputs you connect one wire from each signal source to the data acquisition interface the Micro link. The measurement is the difference between the signal and the ground or earth at the Micro link. This method relies on the signal source being grounded (earthed), and the signal sources ground and the Micro links ground having the same value. Differences in Ground Levels We think of the ground as a constant 0V, but in reality the ground, or earth, is at a different level in different places. The closer together the places, the more likely the ground level will be the same. Make a connection between two grounds and the difference in levels can drive large currents, known as earth or ground loops. This can lead to errors when using single-ended inputs. Noise Errors Single-ended inputs are sensitive to noise errors. Noise (unwanted signal contamination) is added because signal wires act as aerials, picking up environmental electrical activity. With single-ended inputs you have no way of distinguishing between the signal and the noise. The ground and noise problems can be solved by differential inputs. Differential Inputs With differential inputs, two signal wires run from each signal source to the Microlink. One goes to a + input and one to a input. Two high-impedance amplifiers monitor the voltage between the input and the interface ground. The outputs of the two amplifiers are then subtracted by a third amplifier to give the difference between the + and inputs, meaning that any voltage common to both wires is removed. This can solve both of the problems caused by single-ended connections. It means that differences in grounds are irrelevant (as long as they arent too large for the amplifier to handle). It also reduces noise twisting wires together will ensure that any noise picked up will be the same for each wire. Floating Signals A common problem when using differential inputs is neglecting any connection to ground. For example, battery-powered instruments and thermocouples have no connection to a buildings ground. You could connect a battery, for instance, between the Micro links + and inputs. The 2 input amplifiers will try to monitor the voltages + to earth and to ground. However, as there is no connection between the battery and ground, these voltages to ground could be any value and may be too large for the amplifier to handle. For these floating signal sources you should provide a reference. The Micro link has a socket labelled 0V. Run a wire from, say, the wire to this OV socket, either directly or via a resistor. (If your signal source is itself grounded dont make a connection to the Micro links 0V socket.) Amplifier Ability and Operating Range The three amplifiers used for differential inputs are collectively known as an instrumentation amplifier. Ideally, as previously described, any voltage common to both wires (common mode voltage) is cancelled. In practice the two input amplifiers are not perfectly matched so a fraction of the common mode voltage may appear. How closely the instrumentation amplifier approaches the ideal is expressed as the common mode rejection ratio (CMRR). This is the reciprocal of the fraction let through and is usually given in decibels. The higher the rejection ratio the better. Another specification to look for is the common mode range. This is the maximum contamination voltage with which the amplifier can cope. If the difference in ground levels between your interface and signal source exceeds this value, your measurement will be inaccurate. Less Signals with Differential Inputs? An obvious disadvantage of differential inputs is that you need twice as many wires, so you can connect only half the number of signals, compared to single-ended inputs. Should you decide that single-ended inputs are OK for you if you have short signal wires, close together signal sources, and signals larger than around 100 mV for e.g. you can use differential inputs in single-ended mode. To do this short one of the signal wires (usually the input) to the Micro link V input. Differential inputs, therefore, give you the option of either mode. Op-Amp Characteristics: A very typical commercial IC op amp circuit is the 741. This IC has been available for many years, and a number of variations have been developed to help minimize the errors inherent in its construction and operation. Nevertheless, the analysis we will perform here using the 741 will apply to any other IC op amp, if you take into account the actual parameters of the device you are actually using. Therefore, we will use the 741 as our example IC op amp. A differential amplifier connected as an op amp. To the right is a circuit using the 741 op amp IC, with the input and feedback resistors that are required for this circuit to operate properly in an analog computer. Note that there are actually two inputs to the amplifier, designated + and - in the figure. This is because the 741, like all IC op amps of this type, is in fact a differential amplifier. Thus, the output voltage is determined by thedifferencebetween the two input voltages. The +, or non-inverting input, is grounded through a resistor as shown. Thus, its input voltage is always zero. The -, or inverting input, is the one that is actively used. Thus, we establish that the inverting input, which is also the junction of the input and feedback resistors, must operate as a virtual ground in order t

Platonic Paradox :: essays research papers

To research Plato's paradox in the Meno, we can first consult the definition of what platonism is. Websters defines platonism as "actual things are copies of transcendent ideas and that these ideas are the objects of true knowledge apprehended by reminiscence." For this essay, we will assume that trancendency is- "that which is beyond comprehension", and reminiscence as "past experience". The Meno is a dialogue between Socrates, a scholar and Meno, who eventually became an explorer. For this essay, however, we will assume that Meno is at the time of the dialogue, an upper-class citizen of average to better than average intelligence and superior stubbornness. The piece, according to the translation by G.M.A. Grube is thought to have taken place in approximately 402 B.C. in Athens, Greece. Late in the text, a third character, Anytus, a politician, who would eventually be an accuser of Socrates, joins in the dialogue. In the text, Meno in trying to define virtue accidentally slips in to a paradox or contradictory statement, which Socrates immediately refutes. It is the purpose of this paper to recognize the paradox, examine how Socrates disproves the paradox through argument and evidence. Socrates also brings up a key distinction between true opinion and knowledge, relating to the paradox, which will too be examined. Socrates then gives basis for more argument regarding the paradox, and why he does this will also be examined. The initial argument takes place when Socrates challenges Meno to define virtue. Meno does not realize here what he has started. Meno has before inquired whether virtue is a quality that can be taught or if it is a natural trait, that men are born with. Socrates, in method true to form, twists the question and re-poses it to Meno to see if Meno can answer it all on his own. Meno lists what he thinks are virtuous qualities, and is content at that simple definition. Socrates then says: "I seem to be in luck, Meno, while I am looking for one virtue, I have found you to have a whole swarm of them."Meno's frustration begins to set in. He tries theatrical metaphor to define virtue, as well as relating to physical philosophy and philosophers such as Empedocles.Meno at this point gives up and hands the philosophy to Socrates. Socrates presents Meno with a paradox:"....He cannot search for what (a debater) knows- since he knows it, there is no need to search- nor for what he does not know, for he does not know what to look for.

Threat of Global Warming Essay example -- essays research papers

Threat of Global Warming There are two burning questions that I feel need to be answered before exploring the aspects of global warming. They are what is the greenhouse effect and how does the green house effect contribute to global warming? Gases in the atmosphere are transparent to visible light but absorb infrared (heat) waves that are reradiated from the earth’s surface (Cunningham, Cunningham, Saigo 05). However, some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Carbon dioxide is released to the atmosphere when solid waste, fossil fuels (oil, natural gas, and coal), wood and wood products are burned. Methane is emitted during the production and transport of coal, natural gas, and oil and the raising of livestock. The atmosphere, when loosely compared to the glass of a greenhouse, transmits sunlight while trapping heat inside is called the green house effect. The greenhouse effect is a natural atmospheric process that is necessary for life, as we know it. Too strong of a greenhouse effect that is caused by the burning of fossil fuels and deforestation, may cause harmful environmental change. The greenhouse effect is only troublesome when it gets too strong and warms things too much. And that’s just what scientists say has happened over the last 150 years or so as the people of industrialized nations have extracted Earth’s vast buried stores of fossil fuels and burned them. Each greenhouse gas differs in its ability to absorb heat in the atmosphere. Methane traps over 21 times more heat per molecule than carbon dioxide, and nitrous oxide absorbs 27... ...appen if deforestation stopped entirely? Would the greenhouse effect stop immediately or would it take many, many years? We as humans are smart enough to stop doing things that will ultimately destroy human kind. Aren’t we? More studies must be done to find a definitive answer in order to save mankind. Or is this the way that history dictates that in this one million years global warming is inevitable? Works Cited Discovery Channel. 2005. Global Warming.discoverychannel.org. EPA. 2006. U.S. Department of State website. Epa.gov/globalwarming.org. Science Express, 30 September 2004 Knutson, Thomas R. and Tuleya, Robert, Journal of Climate, vol. 17, pp. 3477-3495. Geophysical Research Letters, September 22, 2004. Cunningham, W.P. Cunningham, M.A. and Saigo, B.W., Environmental Science, A Global Concern, ninth ed., publisher, 2005. Threat of Global Warming Essay example -- essays research papers Threat of Global Warming There are two burning questions that I feel need to be answered before exploring the aspects of global warming. They are what is the greenhouse effect and how does the green house effect contribute to global warming? Gases in the atmosphere are transparent to visible light but absorb infrared (heat) waves that are reradiated from the earth’s surface (Cunningham, Cunningham, Saigo 05). However, some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Carbon dioxide is released to the atmosphere when solid waste, fossil fuels (oil, natural gas, and coal), wood and wood products are burned. Methane is emitted during the production and transport of coal, natural gas, and oil and the raising of livestock. The atmosphere, when loosely compared to the glass of a greenhouse, transmits sunlight while trapping heat inside is called the green house effect. The greenhouse effect is a natural atmospheric process that is necessary for life, as we know it. Too strong of a greenhouse effect that is caused by the burning of fossil fuels and deforestation, may cause harmful environmental change. The greenhouse effect is only troublesome when it gets too strong and warms things too much. And that’s just what scientists say has happened over the last 150 years or so as the people of industrialized nations have extracted Earth’s vast buried stores of fossil fuels and burned them. Each greenhouse gas differs in its ability to absorb heat in the atmosphere. Methane traps over 21 times more heat per molecule than carbon dioxide, and nitrous oxide absorbs 27... ...appen if deforestation stopped entirely? Would the greenhouse effect stop immediately or would it take many, many years? We as humans are smart enough to stop doing things that will ultimately destroy human kind. Aren’t we? More studies must be done to find a definitive answer in order to save mankind. Or is this the way that history dictates that in this one million years global warming is inevitable? Works Cited Discovery Channel. 2005. Global Warming.discoverychannel.org. EPA. 2006. U.S. Department of State website. Epa.gov/globalwarming.org. Science Express, 30 September 2004 Knutson, Thomas R. and Tuleya, Robert, Journal of Climate, vol. 17, pp. 3477-3495. Geophysical Research Letters, September 22, 2004. Cunningham, W.P. Cunningham, M.A. and Saigo, B.W., Environmental Science, A Global Concern, ninth ed., publisher, 2005.

Whole Food Nutrition vs. Vitamin Supplements

Whole Food Nutrition vs. Vitamin Supplements Whole Food Nutrition vs. Synthetic Vitamins which is healthier? Ever since I can remember my mom has been a health nut. We have always taken nutritional supplements and eaten organic food as much as possible. Over the years of taking vitamins supplements, I didn’t notice a change in my health. I did notice when I ate whole foods I felt better than when I ate chemically manufactured fast food. The fast food made my stomach burn. I can also remember not eating meat until I went to school. I think that vitamins are a waste of money. All they do is make my pee turn yellow. Whole food nutrition, which consists of fruits and vegetables, whole grains, seeds and nuts, is the only way to live. Fruits and vegetables contain essential vitamins, minerals and fiber that protect us from chronic diseases. Compared with people who consume small amounts of fruits and vegetables, those who eat more generous amounts as a part of a healthful diet are likely to have reduced risk of chronic disease (â€Å"Fruit†). Americans want to believe in vitamin and mineral pills. We spend an estimated $10 Billion on them in 2008, according to the Nutrition Business Journal (â€Å"One a Day†). Major health organizations for cancer, diabetes, and heart disease all advise against supplements in favor of healthful diet rich in fruits and vegetables, whole grains and legumes. Unlike pills, those foods contain fiber plus thousands of health protective substances that seem to work together more powerfully than any single ingredient can work alone (â€Å"One a Day†). Eating whole food is the safest way of getting nutritional support for our bodies and immune system. Since food is not a pill, over dosing is never a problem. Over eating can be a problem, causing weight gain and other health issues. On the other hand over dosing on vitamins can be toxic if taken in high doses for a long time. For instance, beta-carotene can increase the risk of lung cancer in smokers. In addition, a government surveys found that more than 11 percent of adults take at least 400 units of vitamin E a day, a dose that has been linked to heart failure, strokes, and increased risk of death (â€Å"One a Day†). There are foods that provide nutrients that our bodies need instead of having to swallow so many expensive pills. There are foods that provide natural energy for our bodies, foods like fruits, vegetables, whole grains, nuts and beans. People who want to spice up weight loss add cayenne and other spicy peppers and salsas to their diet. Studies show that very spicy food temporarily increase that rate which fat is burned (â€Å"Total†). So instead of taking a fat burning pill, eat fat burning foods. Here is so information on how to spot whole food. Look for foods as close to their natural state as possible. For an example think of the continuum from whole apples to applesauce to cider to apple juice. Be sure you can identify the real food in a product. If you can’t tell what the original source is, then a product has probably strayed too far from its natural state. Experts believe that nutrients likely act differently when they exist in the unique combinations that occur naturally in foods. Fruits, vegetables, whole grains, legumes, nuts and seeds contain a virtual symphony of vitamins, minerals and fiber that likely work together to shore up health and help protect against chronic disease. When you ingest whole food instead of a single nutrient, it’s like walking through an entire forest rather than looking at a single leaf (Palmer). Vitamins have lost their sheen, and there are more doubts than ever about taking them in pill form. Large doses of single vitamins aren’t a good idea, the benefit is doubtful, and some can cause harm (â€Å"Vitamins†). It’s so funny when I walk into a vitamin store and the sales associates run up and offer all the latest vitamin supplements that help this part of the body and that keep you from contracting this disease. I wasn’t looking for vitamins in the first place. I go to vitamin shops for protein powder. Here are some other reasons why I’m not interested in beefing up on vitamin intake. The Physician’s Health Study II, which followed more than 14,000 male physicians for 10 years, found that supplementing with vitamins C and E did not reduce the risk of prostate cancer, cancers in total or major cardiovascular events. And the Women’s Health Study, which evaluated nearly 40,000 female health professionals for 10 years, showed that vitamin E supplements did not prevent cardiovascular disease or cancer (Palmer). Scientist believe that folic acid protects the body from developing cancerous tumors by repairing errors in DNA. Yet too much may actually nurture the growth of tumors once they form. What’s important to note is that this delicate balancing act is mostly a problem with supplemental folic acid, the form of the vitamin added to supplements and fortified foods. Not with foliate, the natural form of the vitamin found in foods. Whole foods first! Manufacturer’s of vitamin supplements make us think that food doesn’t have all the nutrients we need. So they push vitamins for all kinds of things to make us healthy, so they like us to think. After researching, I have found out that B vitamins don’t prevent heart attacks. Vitamin E doesn’t benefit people with Alzheimer’s disease. Vitamins A, C, and E do not offer any cancer protection. But nutrition experts say that getting crucial nutrients from food, when possible, is better than popping pills. The American Dietetic Association, in fact, has updated its guidelines on nutrient supplementation and now stresses that eating a wide variety of nutrient-rich foods is the best way to get needed nutrients and reduce the risk of chronic disease. The update comes at a time when nutrient supplementation continues to be a growing trend in the United States. Americans spent more than $23 billion on dietary supplements in 2007, according to the association's report, and one-third of adults use a multivitamin and mineral supplement regularly. Others use a variety of supplements, which prompts worry among health experts about the potential negative effects of mega doses (Healthday) . So what makes it better to get nutrients from foods rather than pills? â€Å"Foods are special,† said Andrea P. Boyar, an associate professor of dietetic foods and nutrition at Lehman College of the City University of New York. Foods are complex, and the nutrients within them interact in different and more beneficial ways than they would in supplements. Also, many foods contain healthy dietary fiber, which isn't part of a multivitamin supplement, she said. â€Å"Food is still the ideal,† Boyar said, stressing that she means â€Å"whole foods† — those that are not processed or are as minimally processed as possible. Yet Boyar and other nutrition experts concede that supplements can often fill dietary gaps. That's particularly true, she said, for vitamin D and calcium, especially as people age. She also cited iron, which is often needed by premenopausal women, who lose it with their monthly periods. And, for women of childbearing age, folate supplements have been shown to help prevent birth defects. Overuse of supplements, though — and particularly megadoses — worries health experts. Mega doses of vitamin E, for instance, are particularly hazardous, Boyar said. As for the ideal food-supplement balance, Penny M. Kris-Etherton, a nutrition professor at Penn State University, said that â€Å"ideal† depends on the individual but, in general, think healthy whole foods first. â€Å"Food does not just provide one nutrient but a lot of nutrients and collectively helps individuals meet their nutrient needs,† Kris-Etherton (Healthday). Whole Food Nutrition vs. Vitamin Supplements. That’s what medical scientist and research professionals are trying to determine. More and more, medical doctors are seeing individuals who practice whole food nutrition maintain a lifestyle of health, healing and vitality. Medical doctors, medical scientist and research professionals want to know why and how whole food nutrition accomplishes this. They also want to know what effect whole food nutrition has on improving the health of individuals with certain diseases, such as cancer. Medical/Scientific research is presently being conducted at various hospitals throughout the United States to see what, if any, health benefits whole food nutrition, (i. e. fruits, vegetables, berries) has on individuals with certain types of cancer. This is being done through the National Institutes of Health and the National Cancer Institute. This medical research is â€Å"gold standard†, that is, peer reviewed and will be published in medical journals. This research is exciting and the results are highly anticipated. As shown, we as a nation, spend a great deal of money trying to improve our health with vitamin supplements, when, what we might just find from this research is what Hippocrates, (300 BC), the Father of modern medicine, said: â€Å"Let medicine be your food, and food be your medicine. Words: 1,598