The Status of the P versus NP Problem Essay Example | Topics and Well Written Essays - 500 words

The Status of the P versus NP Problem - Essay Example With innovations in computational power, there has been an increase in algorithms that are much smarter than before. Under such circumstances, the pressure to tackle P versus NP problem, is considerably increasing. Moreover, this P versus NP problem is invading all fields of science as just not a theoretical question but as a basic principle. Author of the article surmises herein, the simple description of the issue and the change in working direction related to computer science attained because of efforts to solve this question. P versus NP problem actually computes combinational issues. Jack Edmonds, first in the history, provided a program that can help in developing a program to solve combination problem, and formally defined it as ‘efficient computation’. P in this problem stands for ‘Polynomial Time’ and defines problem class which has efficient solution. Likewise, NP in this problem stands for ‘Nondeterministic Polynomial-Time’ and refers to the problems that have solutions that can be verified in an efficient manner. Furthermore, author describes that extremely complicated NP problems are termed as ‘NP-complete’ problems. Examples of such problems are Clique, Partition and triangles, 3D-coloring and Hamiltonian cycle. Basically, the idea promoted by NP-complete asserts that if an efficient algorithm can be developed for one problem, it can also be developed for other complicated problems too. Thus to simplify, P defines the type or the category of the problem that comes with efficient solution whereas, NP defines a group of problems, each of which has an efficient recognizable solution. By saying P = NP, we mean to say that for any problem that has an efficient verifiable solution, we can efficiently identify that solution. However, there are many scientists who believed that P ≠  NP and defined it as inability to find the solution efficiently. The author presents several attempts to prove a problem that is

Reading Review Assignment Example | Topics and Well Written Essays - 750 words

Reading Review - Assignment Example Theses artists perceived revolutionary leftist politics as the sole hope against abuse and violence. They therefore placed hope in political art as opportunities to bring change. To communicate to masses of people, the artists organized realism, a style that most people preferred and understood (Barber 31). Some artists such as Diego Rivera used their art to protest social ills. In 1950, Rivera created an artistically huge, multi-layered mural in Mexico City. He drew his ideas from the early colonial manuscripts, Pre-Columbian sculpture, and historical accounts to compose idealistic portraits of utopian Indian traditions, on-going resistance to the dominant Spaniards, and radical assault on imperialist vices. Rivera’s use of new technologies in art was used to protest social evils and had clear appeal to leftist politics, an appeal that expanded to the U.S during the age of depression. Most of researches from art works indicate that femininity failed to fulfill most of the requirements of traditional art history. In the 19th century, these practical limitations did not affect women as much, but in the early years of the 20th century, women were gradually marginalized from paintings. Women, whose reputed powers were in intuition and emotions as opposed to reason were perceived as incapable of delivering symbolic and intellectual arts properly. History art depends on a clear creation of articulated texts, where texts are clearly employed to meet discursive objectives. Similarly, the temperaments needed of a history artist begun to be gendered as â€Å"masculine† thus implying that none of the women artists would have the frame of mind essential to create significant historical art. Since art displayed and needed judgment and imagination; a couple of components of reason, they were traditionally associated with masculinity. A notion came

Television as the Substitute Good Essay Example for Free

Television as the Substitute Good Essay Studying the conditions, it can be understood that the television set is a substitute good of the television repairmen. Meaning, if the cost of hiring repairmen goes up, the demand for television sets will rise (Piana 2005). Although this may seem counter-intuitive, it makes much more sense when the problem is closely observed. Firstly, we take only in consideration the two goods given: repairmen and television sets. It does not follow that television sets have an absolute need of repairmen for the industry to survive. When a television set breaks, hiring a repairman is not the only option. The second option is the second good itself. People have the option to simply buy a new television set. It is true that the market of repairmen is dependent on the demand for television sets but the scenario asks for the opposite. The market of television sets does not rely on the demand of repairmen. Overall, we can say that the increase of repairmen cost per hour will increase the quantity of new television sets sold. If the cost of television repairmen becomes too high, people will have the tendency to buy new sets instead of hiring repairmen. Of course, this scenario relies on the condition that other goods in the market are not considered. If we take into consideration goods that rival the television such as computers and what not, then the market for television sets may go down with the repairmen. However, the problem must be limited to the given and all other factors cannot be applied. Since television and repairmen are the only ones to be considered, then the prediction above is more or less acceptable.

Kinetic Energy Recovery System (KERS) For Vehicles

Kinetic Energy Recovery System (KERS) For Vehicles During deceleration, traditional brake of a vehicle transforms the kinetic energy into thermal energy. This is due to the fact that when brakes are applied the friction between the brakes shoe or the calliper as used in modern disc brakes and the wheel not only restricts the motion of the wheel but at the same time a lot of heat energy is generated due to this braking action. Unfortunately there is a huge waste of the generated energy in the form of heat as a large amount of it dissipates into the air. Hence in order to make use of this heat energy, the idea of kinetic energy recovery for vehicles has been explored. Although this system is in use in motorsport and other few selected high performance fields, method like using regenerative brake to generate electric energy is already used in hybrid cars. However, transforming the mechanical energy into an electrical form has a limited efficiency and is not an easy task, but requires complex mechanical systems. Working By using acceleration sensor controlled gear box, acceleration and deceleration could be performed by the transfer of mechanical energy between the vehicle and its energy storing unit, thus reduce energy consumption. The design contains three basic parts: a control unit, an infinitely continuously variable transmission gearbox and an energy storing unit. There are two possible solutions for the energy storing unit: a big torsion spring or a flywheel. Both the two solutions work with the system. THE SPRING SYSTEM: During deceleration of a train, instead of using break, the wheels are connected to a torsion spring with the help of the gearbox. This in turn transforms the kinetic energy into the springs potential energy. However, the spring does not provide constant torque, according to Hookes law. In order to perform stable deceleration, the sensor controlled gearbox changes the gear ratio through a continuously variable transmission mechanism. The desired deceleration rate is determined by the driver. The acceleration sensor senses the actual deceleration rate and gives accurate feedback. Through a feedback control loop, the gear ratio is adjusted continuously and deceleration rate can be maintained at the desired level. In cases when spring has its maximum load, normal braking is activated. When the train stops, the spring will be held. When the train starts again, instead of using its engine or motor, the gear box connects the spring to the wheels but in an opposite way to drive the train. T he acceleration torque provided by the spring decreases with the release of the spring. Again, through sensor feedback control loop, the transmission gear ratio is adjusted continuously to maintain the acceleration rate. Once the spring is fully released, the motor is again activated. THE FLYWHEEL SYSTEM: System with a flywheel works in a similar way. Energy is stored into the wheel by increasing of the spinning speed. In order to provide constant torque transmission gear ratio need to change. With the implementation of acceleration feedback control, the braking output could be adjusted through changing the transmission gear ratio. The kinetic energy could be completely (except the loss on bearings and transmission gears) stored during braking and given back during acceleration. This system could work with both combustion engines and electric motors. Thus the limited energy recourses could be saved. KERS is essentially an energy-storing flywheel attached to an efficient Continuously Variable Transmission. Under braking, energy that would usually be expended as heat is instead used to accelerate the flywheel. When needed the power can then be used to augment that of the internal combustion engine What makes the system green isnt the added performance, but the use of energy that has traditionally been wasted. Working and Specification Kinetic Energy Recovery System  (KERS) is the word which is being associated with Formula 1 cars and has been in the Headlines for quite a while. All 2010 Formula 1 cars feature KERS as an integral part after it was made mandatory by FIA to be installed and is currently being manufactured by  Flybrid Systems. What is KERS? KERS  as the name suggests is an energy recovery system also known as regenerative system but importantly the KERS is quite advanced than the conventional energy recovery systems. The mechanism functions in a way that it reduces the speed of the vehicle by converting some of its kinetic energy and/or potential energy( in case of elevations) and storing it into a useful form of energy instead of dissipating it as heat as seen in conventional dynamic braking system. Technically KERS can be defined as an Electric generation, storage, and propulsion system generating electricity during slow down or braking, storing it in batteries, and later assisting the gasoline engine by boosting acceleration with the help of electric drive motors. The device will be installed in F1 cars to save energy utilized while braking, store it and further use it when required. KERS is of two types one mechanical and the other electrical. What does KERS contains? The system basically consists of a CVT( Continuously Variable Transmission ) unit , a clutch, an epicyclic gearbox and a flywheel (The mechanical type contains a FLYWHEEL to retain power while the Electrical type contains an electric motor twinned with a BATTERY or CAPACITOR or FLYWHEEL) Working of Kinetic Energy Recovery System The engine drives the KERS system and it is coupled with the drivetrain. The drive comes into the CVT unit which effectively changes the gear ratio in accordance with the flywheel and rotates the flywheel. The control pistons seamlessly change the gear ratios between the input and the flywheel moving at a much faster rate than the actual drive (5:1 ratio at 64,000 rpm). The amount of energy stored or released depends upon the torque transfer taking place within the CVT unit, which is controlled by the position of the levers. Conclusion KERS is a particularly appealing proposition for road-going vehicles because of its lack of weight and relative simplicity over the energy storing systems in current hybrids like the Toyota Prius. KERS doesnt need batteries and is therefore free of their weight and the environmental impact that comes from creating and disposing of them. In city riding KERS would have a significant impact on emissions, providing emissions-free power for initial acceleration away from stoplights and similar. In performance applications the system could provide on-demand extra power for overtaking or accelerating hard out of corners, using power that wouldve normally been wasted as brake heat on corner entry. More power using less fuel can be easily achieved.

Medea - the conception of drama within theatrical production :: essays research papers fc

â€Å"The Conception of Drama within Theatrical Production†   Ã‚  Ã‚  Ã‚  Ã‚  In Euripides’ tragic play, Medea, the playwright creates an undercurrent of chaos in the play upon asserting that, â€Å"the world’s great order [is being] reversed.† (Lawall, 651, line 408). The manipulation of the spectators’ emotions, which instills in them a sentiment of drama, is relative to this undertone of disorder, as opposed to being absolute. The central thesis suggests drama in the play as relative to the method of theatrical production. The three concepts of set, costumes, and acting, are tools which accentuate the drama of the play. Respectively, these three notions represent the appearance of drama on political, social, and moral levels. This essay will compare three different productions of Euripides’ melodrama, namely, the play as presented by the Jazzart Dance Theatre ¹; the Culver City (California) Public Theatre ²; and finally, the original ancient Greek production of the play, as it was scripted by Euripi des.   Ã‚  Ã‚  Ã‚  Ã‚  The two contemporary productions of Medea were selected for this essay in an effort to contrast the ancient Greek version of the play with two modernized versions, which would demonstrate a wide distinction between the styles of production. Furthermore, both modernized versions of the play add their own innovation to the production, making for an even broader dissimilarity among the plays. Moreover, both recent productions are fashioned within cultures which have borrowed their political, social, and moral ways of life from Ancient Greek society, specifically, South Africa ¹ (British Colonies), and The United States ².   Ã‚  Ã‚  Ã‚  Ã‚  Based in Cape Town, South Africa, Jazzart Dance Theatre is known today for its distinctive style and ingenuity in extending the boundaries of South African dance. Contrarily to the original production of Medea, Jazzart’s unique approach uses dance (as opposed to music) to articulate emotion to the viewers. The dancers reinvent Greek tragedy, harbouring no artistic safety net.   Ã‚  Ã‚  Ã‚  Ã‚  The set plays a central role in dramatizing the theatrical experience of this particular production. As you can see in both figures 1 and 2, the set is purposely designed to resemble a metropolitan alleyway. This dramatic ambiance is created in an effort to parallel the harshness of the unforgiving streets of any particular conurbation. Normally, the audience would tend to construe this setting as a symbol of turmoil in the kingdom of Corinth. Thus, the set itself works as a device in developing a sense of political drama.   Ã‚  Ã‚  Ã‚  Ã‚  The costumes which are used for this particular production are also essential in dramatizing the on-stage action.

Cyclical Structure of Narcissus & Goldmund by Herman Hess :: Goldmund Herman Hess

Cyclical Structure of Narcissus and Goldmund    Narcissus & Goldmund, by Herman Hess, contains a distinct cyclical structure. This structure is contributed to through characters, themes, ideas, times, and places. Each of these elements facilitate the development of an organized, creative work, delving deep into the human psyche to reveal that both Narcissus and Goldmund are players in the same game. There are three separate cycles present in the novel. The first cycle occurs during the first year or two after Goldmund has left Mariabronn. It concludes with Goldmund witnessing a woman giving birth. He sees in her face the face of all of the women he has ever been with, and this connection between love and birth purges him of the sterile passion he felt for Lydia. Characters in this cycle, almost exclusively women, are seen as objects. They are erotic, sensual, and physical, but nothing else. They have no dimension beyond that of a sexual outlet for Goldmund’s blind passions. There is an impression of a transience present in the mother-world, manifested in Goldmund’s many relationships. This is demonstrated most clearly through Lise, when, after she and Goldmund make love together, returns to her home for the night. This happens with other characters as well, most of them having husbands to return to, and Goldmund feels pain because of this knowledge. All of the meetings between Goldmund and his lovers occur at night, and bears a strong relationship with nature, specifically, animals, trees, and plants. As the cycle continues, Goldmund experiences death as well as life, demonstrated by his killing Victor over a gold coin. Ideas presented within this cycle include the need for commitment. As Goldmund was before a spring lover, he is now a hunted murderer, but he does not at this point in the novel, realize that death, equated with the season of winter, are elements of the mother world. The second cycle beings after Goldmund witnesses the woman giving birth. In this cycle, Goldmund sees death and d ecay, and the beauty present in each. From Niklaus’ statue, Goldmund begins to see the blending of beauty and pain, and he decides to pursue the world of art, under Niklaus. Goldmund sees in art a blending of the mother and father world. The characters Goldmund comes in contact in this cycle give a definite image of pain and death. This is exemplified in the plague scene, wherein Goldmund comes to terms with death, and understands how it transcends, as art does, the mother and father worlds.

Donnie Darko †English assignment Essay

Donnie Darko is a film by Richard Kelly from 2001, with Jake Gyllenhaal in the main lead. The film is supposed to look like it’s from 1988. The film is about a schizophrenic teen that lives in the American suburb of Middlesex. When an unidentified giant plane engine crashes into his room, a chain of mysterious events is triggered. Donnie is plagued by visions of an evil-looking rabbit named Frank. Who makes Donnie commit acts of violence, and tells him the world will end in 28 days. Frank is the boyfriend of Donnie’s sister Elizabeth. The Frank who speaks to Donnie is a kind of ghost Frank – a remnant of Frank, because Donnie shoots him in the eye within the Tangent Universe’s 28 days and can move freely in time throughout the Tangent Universe. Compare Donnie to one or two of the characters in the short stories we have read about the topic – In all the readings we have done in the other texts from Context, the subject have been â€Å"growing up†. All the other readings have been about different children growing up in different environments, though any of them haven’t got any psychological problems. I don’t think that any of the characters from all the other readings we have done, that there are any personalities like Donnie’s. Donnie is suffering from schizophrenic. People with schizophrenia often suffer terrifying symptoms such as hearing internal voices not heard by others, or seen things not seen by others. That is why Donnie often is seeing a therapist and why he is on medication. Though there is â€Å"The Sin Bin or Lucy’s Heart† reading where Lucy is been told to do mean things to a girl named Penny by Bethan. Which she regrets such as Donnie also does. Just like Donnie is been told to overflow the school. But I don’t think any of our readings can be compared to this movie. All the readings we have read takes subject in bulling, a hard way to grow up and so on. There is no greater meaning in texts. In Donnie Darko there is a meaning with everything he does and with every thing there take place in the film. Frank makes Donnie flood the school, giving the lucky students a break from classes. And then he walks Gretchen home and convince her to â€Å"go with him†, and says he is happy the school flood, or else he hadn’t had that conversation with her. So I believe Frank made Donnie do it, so he could meet Gretchen. How can the plot of the film be explained? Can it be explained in more ways? – The plot can definitely be interpreted in many ways. I also think many people doesn’t get it, in the way it’s supposed to be interpreted. Or maybe it’s actually supposed to be in a way, which can be discussed over a longer time and interpreted in many ways. I’ve myself used a lot of time discussing this movie. I would rather do some short but very interesting sites of some of the main characters, and what I think is the deeper meaning of some of the characters. I see Donnie as Jesus; he died to save mankind – just as Donnie did. Frank I see as Satan, deceived Donnie for his own benefit. Roberta Sparrow as God. I feel like she is the facilitator of all this. She once was a nun, she wrote the book on time travel and she knows Donnie’s letter is coming. Then there is the Chinese girl Cherita, whom you don’t see of follow that much, but I can’t stop thinking that she is Donnie’s â€Å"Guardian Angel?† She always seems to be behind Donnie watching over him, and she has a notebook about him. I don’t know if that is a right observation, but I can’t stop thinking that way – and I am not even religious. Comment on the ending of the film – how can it be interpreted? – Donnie is having a Halloween party, where Gretchen is with him. Donnie goes to the fridge where a note is saying, â€Å"Frank left to go get beer†. Then Donnie takes Gretchen to go see Roberta Sparrow, Grandma Dead, because times almost op. Two thugs then attack Donnie and Gretchen, which are two guys from their school. One throws Gretchen onto the ground; the other holds a knife to Donnie’s neck. Roberta is standing in the middle of the road and a car tries to avoid her but then hits Gretchen and kills her. The driver is Frank; this is the real Frank – Donnie’s sister’s boyfriend. Donnie gets scared and frightened and shoots him in the eye. With Gretchen’s body at his side, Donnie watches a storm begin. Donnie then remembers what Gretchen said about taking back all the bad things and replacing them with something good. Donnie then goes back in time trough the wormhole and changes the future with him staying in bed. With him staying in bed and the crashing hits their house Donnie gets killed. Gretchen lives on, without ever knowing Donnie. I think Gretchen feels some kind of dà ©jà   vu when she sees Rose. Gretchen actually doesn’t know Rose yet, but she did before Donnie went back in time. You get the feeling that Rose and Gretchen seem to recognise each other by _way they look at each other.