Managing User Accounts In Linux Essay Example for Free

Managing User Accounts In Linux Essay Linuxs most notable advantage over other operating systems such as Windows and Mac is security and in order for a user to modify critical components of the system, such as user accounts, is to have access rights of a ROOT. The root is at the top level of Linuxs user hierarchy and has all the privileges to access all resources. To login as root, a user must use the command su username. After pressing the ENTER key, the system will prompt the user to type in the corresponding password. After entering the correct password, the user will inherit full access privileges including the right to modify other users account information. Attempting to enter the correct password will deny the user from inheriting the roots privileges. # su [screenshot] Let us now attempt to create a new user called bozo. But first, let us check if that username is not yet taken. # id bozo [screenshot] Since username bozo is still available we can now create his user account. # useradd bozo -d /home/bozo -u 600 We have just created a username called bozo and makes his default folder under /home/bozo and gave him the UID of 600. by the way, UIDs are unique identifiers of users. Users can be a representation of both human users and services running in the Linux system. UIDs are used by Linux in relation to his password and privilege information stored in the /etc/passwd, /etc/shadow and /etc/group. One of the very first thing Linux does when creating a new user is to copy the files from the skeleton folder, which contains whatever files the admin wants to give to new users, into the newly created users folder. Now, let us try to take a look at those files by displaying a detailed listing of files including hidden ones. # ls –la /home/skel/ So far so good. Now let us try creating another user and call her bozoette. # useradd bozo -d /home/bozo -u 600 We had an error. As stated earlier, UIDs are unique. Since we attempted to create a user and assigned the same UID with bozo, the system denied our request. But what if we do want give bozoete the UID #600? One of the many ways to do it is to first change bozos UID, say 601 and then create bozoettes user account using the newly-vacant UID of 600. Change bozos UID from 600 to 601. # id bozo # usermod -u 601 bozo # id bozo Then create bozoettes new account with UID 600. # useradd bozoette -d /home/bozoette -u 600 Now we have two new users bozo(uid:601) and bozoette(uid:600) with user directories /home/bozo and /home/bozoette, respectively. Note that user accounts remain inactive until a password is assigned to them. Let us now activate the two new user accounts by assigning passwords to them. # passwd bozo # passwd bozoette Users bozo and bozoette are now active and users can now login to the system using the correct username and password combinations for the accounts. REFERENCES Linux Headquarters. Adduser: Adding A New User. http://www. linuxheadquarters. com/howto/basic/adduser. shtml Advanced Horizons. Linux Users. http://www. ahinc. com/linux101/users. htm Mario P. Free November 28, 2007. Tutorial @HowTo. fm. Command Line User Management. http://howto. fm/e/a/title/Command-Line-User-Management-in-Linux/ Notaras, George. 6 November 2005. G-Loaded! User management from the command line http://www. g-loaded. eu/2005/11/06/manage-users-from-the-command-line/

Students stress Essay Example for Free

Students stress Essay ?Introduction paragraph: As we know going to college has a huge importance for every student. Obviously students gain different experiences from each other. Becoming a student has advantages and disadvantages. This essay introduces us with one of the disadvantages which is students stress. Financial problems , time management , changing sleeping or food habits and social activities are some effects and causes that induce students stress. Body paragraphs Topic sentence : Time management is an effect that induces students stress. Connecting explanation: When students don’t manage their time appropriately they find it difficult to study. Detail / Evidence 1 : Not being able to arrange their time ,they find it difficult to find the right time to study or work (or any other activity) Detail / Evidence 2 : The more time spent at work (or different activities), the less time a student spends studying. Example 1: Having to hold down a job and still be a college student is a constant source of stress (Calderon , Hey Seabert , 2001). Connecting explanation : The students that work or attend to social activities find it hard to manage their time so they can achieve what they want. Concluding sentence : As we see from the example above students that don’t manage their time have lots of stress. Time management is an effect that induces students stress. Being regular attendees to different activities makes them to have less time to study. Having a work also complicates the ability to manage their time appropriately. It is important for every student to have at least a guide that explains how they can handle this stress. Being able to manage our time helps us a lot to achieve in the appropriate way our studies , work and social activities. Topic sentence : An important cause that leads to students stress is financial problem. Connecting explanation : Having financial problems it is surely the best way to distract students from their studies. Detail / Evidence 1 : Financial support is a tremendous factor in the success of a college student. Detail / Evidence 2 : The need for financial support leads students to take care of job responsibilities. Example 1 : If the student has a family that involves his or her own children, the support of everyone is needed even more to achieve the goal of graduation (Trockel et al , 2000). Connecting explanation : Not having a financial support leads students to take job responsibilities which causes lots of stress. Concluding sentence : As we see in the example above the support of the family is a huge importance. Having financial problems it is surely the best way to distract students from their studies. Finding how to manage their costs is obviously very stressful. The reason that obligates students to take care of job responsibilities is the lack of a financial support. Being free of financial responsibilities is a relief for them. According to the example , to achieve the goal of graduation the students families must give them support. Topic sentence : Changing sleeping habits its another cause that creates students stress. Connecting explanation: When students go to college change their sleeping habits because of job responsibilities or social activities. Detail / Evidence 1 : Sleep deprivation causes shortened attention span. Detail / Evidence 2 : Increased number of errors that students make on a test. Example 1 : Sleeping shorter amounts of time has shown to increase factors such as anxiety and stress which have been associated with academics performance (Celly et al 2001). Connecting explanation: Usually students that change their sleeping habits for different reasons tend to lose their attention which reduces their grades. Concluding sentence : According to the example above , sleeping less causes much more stress which lowers the academic performance. Changing sleeping habits its another cause that creates students stress. Most of the students when they go to college start a work or attend to social activities which makes them sleep less. A low attention its obviously a lack of sleep. Not being careful to their courses makes them lose lots of information and increases the errors in their tests. According to Celly (2001) Anxiety and stress come from a low amount of sleep and that’s what leads to a reduced academic performance. Topic sentence : Being part of social activities is another cause that induces students stress. Connecting explanation : Following social activities spends the students time more than it should. Detail / Evidence 1 : Taking time out of frequent study hours to work out pulls away from grades. Detail/ Evidence 2 : Exercising too much or not at all can influence academic performance. Example 1 : Students who exercised seven or more hours a week obtain significantly lower grades than students who exercised 6 or fewer hours weekly or not at all. Connecting explanation : Exercising too much reduces students academic performance which leads to lower grades. Concluding sentence : According to the example above , we can see the importance of not spending too much time in different activities. Being part of social activities is another cause that induces students stress. We all know that following social activities is good when its not exaggerated. It is obvious that spending lots of time in activities doesn’t give us the opportunity to study enough. Not studying enough surely reduces students grades. According to the example above , students should understand the importance of spending appropriate hours on social activities. Topic sentence : Another cause that induces students stress is changing food habits. Connecting explanation : Because of different things that students might have during their college they don’t have enough time to cook so they change their eating habits. Detail / Evidence 1 : Having an unhealthy diet is an important detail that leads to students stress. Detail / Evidence 2 : Learning to cook is a new challenge for students. Example 1: Little storage space is available in the average dorm room , and food storage may not be possible at all (Trockel et al , 2000). Connecting explanations : Many students consider learning to cook as a challenge so they choose to have an unhealthy diet which causes stress for them. Concluding sentence : According to Trockel (2000) the reason that students choose to have an unhealthy diet is because of the little storage space available in the average dorm room , or the food storage might not be possible at all. Another cause that induces students stress is changing food habits. Students before going to college were used with moms cooking. Now they have to do everything on their own , concluding cooking. Because of many students consider cooking as a challenge they go to the supermarket to buy something to eat. Having an unhealthy diet its proved that lowers the capacity to study and this causes students stress. According to Trockel (2000) the reason that students choose to have an unhealthy diet is because of the little storage space available in the average dorm room , or the food storage might not be possible at all. Concluding paragraph : As we see there are lots of causes and effects that induce students stress. Last year I was a freshman in an Italian university and I can say from my experience that is very difficult to handle a stress that college induces. I think that those causes and effects are parts of every students life that is why they shouldn’t freak out. Knowing how financial problems , social activities , time management , the change of sleep and food habits effect students should also be a good priority for studiers to find a way how we can handle it. Capable students obviously will be an important step that will lead us to a better future.

Creating a Suitable Braking Assembly

Creating a Suitable Braking Assembly To understand the advanced material and processing technologies specifically to study the interaction between different materials and the design process to create a suitable braking assembly consisting of disc, caliper and brake pads. Disc A disc brake or rotor is used to stop or slow down a moving vehicle. There are two types of disc brakes namely solid and ventilated disc .The rotating disc is connected to the axle and rotates with the wheel. When brake is applies the kinetic energy is converted to thermal energy. The temperature range of a disc braking under braking is 400C-600C. The weight if the disc also matters. For better braking and longer disc life. The disc should have grooves to disperse water to give maximum performance under wet conditions. Disc which are likely to corrosion are coated with anti rust paint. It should be resistant to wear and tear. The reliability of the disc increases when it responses fast and gives safety in all situations. Caliper The main function of the caliper is to hold the brake pads and to hub the brake fluid. The caliper is the actuator in braking and is attached to the steering knuckle. The pistons inside the calipers push against the brake pads which rub against the disc. There are two types of caliper-floating and fixed calipers. Fixed type does not rotate and are fixed. Floating type rotates in relation with the disc on an axis. The caliper should be clean and dirt free for maximum performance. It should also be corrosion resistant. Since calipers are actuators, they have to be made for maximum safety. Need to check if all the pistons are working or if they are engaged. Calipers should also dissipative heat produced. The calipers should provide complete safety in all conditions. Brake pads Brake pads are friction materials mounted on the caliper. They have high friction and help stop the vehicle. They wear out and have to be replaced for better braking. Brake pads or friction pads are the most important part in a brake assembly as this is the part that stops the vehicle. The most important property of the pad is the have a constant high coefficient of friction in a wide range of temperature. The pads should have enough surface area. Heat produces during braking should be dissipated or absorbed. It should have high melting point or the pads could face a phenomenon called brake fade. The brake pads must not wear out rapidly neither should it wear the disc. All the braking action should be quiet, even and stable. Disc Since the disc is thin, the material should be high compressive strength and should not deform under pressure or stress. Therefore the disc rotors need to have high melting point, high dynamic and thermal stability. Rotors should also be wear and rust resistant. The material should also have high dampening to absorb all the vibrations and noise when braking. It should also high have high thermal conductivity and should dissipate heat quickly. It should be able to minimize thermal expansion and should also be hard enough to withstand cracking. Finally the material should have superior machineability and castability. Caliper Material selection for caliper is crucial as it takes in high pressure and stress. It should be light and should have high tensile strength. The pistons should be made of high strength materials to transfer the force from the hydraulic fluid to the brake pads for effective braking. The material should not deform under high stress. Caliper design can get complicated so it should be easy to machine. The material should help in absorption and dissipation of heat and vibrations. Moreover it ought to be rust and dirt resistant. It should also exhibit high dynamic and thermal stability. Brake Pads The material selection for brake pads must have high coefficient of friction for a wide range of temperature and high melting point. Moreover it should withstand heat and dissipate quickly. Another desirable quality of the material is low dust and also low NVH which gives brakes a quiet operation. The material should provide a fade free operation and help eliminate rotor squeal. Pads should have long life but should be rotor friendly also. Since the pads are replaced frequently the pads should be easily machineable and the materials should be easily available. Disc and Caliper The material selected for Disc rotors and caliper is Cast Iron. Cast iron is an alloy of iron and carbon, where the carbon presence is about 3%-4.5% by weight. It is popular because of its low cost and ability to take complicated shapes and ease of machineability. The mechanical properties can be divided into the following Tensile strength-Cast Irons have comparatively less tensile strength but it serves the purpose in disc brakes. The strength is of the magnitude of 7 tonnes per square inch. Hence making the disc brake safe under tensile loading. Compressive strength-Cast iron is popular for its high compressive strength and can take the high compression from the friction material under braking. Consequently brake caliper can take in high load and resist bending or crack. High melting point-The melting ranges from 1140C to 1200C, which is more than sufficient for disc rotors. This helps in removing the disc fade phenomenon and helps braking more efficient at high temperature. Resistances to deformation-Cast irons resist any form of deformation and give a very rigid frame. Hence any form of cracking or breaking is eliminated by careful manufacturing methods. Resistance to Corrosion-Cast iron provides resistance to rust as it inhibits the oxidation of iron. But any part subjected to rust is coated with paint for extra protection. Wear and tear The chosen material is known for its hardness. Wearing out or eroding cast iron is incredibly difficult. Cast iron has proved its excellent abrasion resistance for years. For this reason, cast iron has been selected for disc rotors and caliper for excellent braking performance. Durability and Environment Issues Cast Iron are known to have high durability against fuels where the disc and caliper are often in attendance. The hydraulic fluids used in calipers cause no harm to the metal and hence provide good braking. Cast irons are environmentally friendly material which can be recycled and also doesnt require high energy in machining which reduces cost and pollution. Therefore Cast Iron proves to be the suitable material for disc rotors and brake caliper as it serves the entire design requirement. Adding to the qualities is the dampening ability which helps in NVH free running. It even has an extremely low coefficient of expansion .moreover it also has low sound emission level and also dissipates heat quickly. All these qualities add up to make the cast iron the suitable material. Pads The material selected for brake pad is Asbestos because of its high coefficient of friction. It mainly found in silicate minerals and usually found as long, thin fibrous crystals. Asbestos became popular with its physical properties and came to be used widely in spite of its health hazards. The physical properties are divided below. Tensile Strength Asbestos is known to have very high tensile strength which makes it perfect for use as brake pads. As the brakes are applied at high speed, the pads are rubbed against the disc at high speed producing high tensile force. Therefore asbestos provides the require strength to counter it. High Melting point Asbestos has melting point in the order of 1200C-1500C.This helps in removing the fear of brake fade giving high performance even at high temperatures. Resistance to deformation Asbestos is found to be flexible material. The flexibility of the material helps it to change angle and help increase the braking as the surface of the pads will be evenly run over the disc generating excellent braking. Adding to flexibility is its high tensile strength. Wear and tear Asbestos has high coefficient of friction which makes it perfect but since asbestos are fibers, they tend to wear out but on a reduced or controlled rate according to the manufacturing method. They are designed to wear out eventually. But asbestos are durable material resistant to a number of elements. Environmental issues Asbestos are not environment friendly material neither is it safe for humans. Its fibers often cause health risk which makes it quiet dangerous to use. Asbestos has a number of outstanding abilities such as heat, fire, chemical, friction, electrical, acoustical resistance. All these qualities help in providing a smooth braking feat. It insulates heat and helps dissipate heat quickly. The acoustical properties help absorb the noise and sound and give a quieter operation. Since its chemically inert, it helps in operation in any conditions. Moreover it is insoluble in water and corrosion has no effect. All these qualities add up to prove that asbestos is a good material for brake pads. Disc Disc brake rotors are made using a simple process of casting. Casting is a manufacturing process where the selected material is poured into a mold which has the shape and geometry of the design and then allowed to solidify. Once the metal is solidified, the finished product is taken out by ejection or breakage of mold. Casting is also helpful in mixing two or more materials.The current manufacturing route for the disc brake rotor is casting as cast iron has excellent cast ability and machineability. Since casting has been used for a very long time, it has been developed over the years too. Its economical because of the low equipment cost and tooling cost which helps keep cost down. Disc rotors are made using sand mold. The disc shape is made in a sand cavity and molten cast iron is poured into the cavity. The liquid metal flows to all the space and empty crease in the cavity and takes the shape of the mold. Once the mold shape is taken, it is allowed to cool. After the mold has been cooled to a temp where it can be taken out of the mold, the product can be ejected or the mold can be broken to take the product. Once it is casted, the shape of the disc rotor has been created. It then goes for machining where it is trimmed to final dimensions and level the surface for critical surfaces/dimensions. After machining, the disc is taken over to surface abrasive section where all the rough edges and surface are made clean and smoothen to increase smoothness. After all the work has been done it might be given a coat of anti rust or left over for packaging. Many disc manufacturers drill holes and mill the disc rotors for better air flow and heat dissipation. Casting is a low cost process but often it come with flaws. The rotors would have sand inclusions, bubbles, porosities and usually end up in one piece which can induce really high stress. This can cause uneven cooling or heating and produce cracks in the rotor. Once a crack is formed in a disc, it can lead to the destruction of the whole disc. Therefore the cracks should be taken care of beforehand. To counter this problem, many companies resort to what is called ASTM high temperature cast iron. They use vacuum assist degassed to eliminate the pososite to help stop cracking. Caliper The selected material for caliper is cast iron. Since cast iron have good castability, calipers are also made from casting. But since calipers take a very complex shape and have minute detailing, a high pressure casting is used. High pressure casting is similar to sand casting except that very high pressure of the order 14-140MPa is used to force the liquid to the mould giving good surface finish and also production of very thin sections. The process involves the cast iron melted to be flowing liquid. A mold of the caliper is made and the liquid is injected to the die using a plunger. The liquid fills the die cavity and since high pressure is used, the liquid goes to the smallest creases and takes the whole of the die space leaving less room for inclusions or porosity. Once the liquid is cooled, the die is opened and the product is taken out for further processing. Since the surface finish is good, there is less need to machining. It may be treated with chemicals and all the complicated shapes are cleaned. The caliper is given a protective paint coating for anti rust property. The major advantage is of the high pressure casting is the high production rate compared to sand cast. This is the current route of the manufacturing of calipers using cast irons. Pads Pads are manufactured rather traditionally. Basic process involves cutting of 2 metals one with a friction lining and then sticking them together to make the brake pad. The process starts with cutting two sheets metal. One metal will have the friction material and the other metal will act as a carrier. Once the sheet metals are cut, the two metals are bonded together by a damping layer. The damping layer is an adhesive that sticks both the metals together. Its a layer is a peroxide-cross linked polyacrylate adhesive of a thickness of about 75 ÃŽ ¼m or a peroxide-cross linked silicone adhesive of a thickness of about 100 ÃŽ ¼m. First the damping layer is applied onto one material and then the metal is pressed to the other metal. Few individual supports are punched out from the metal bonded together, providing support on one side and friction on the other. Thus the brake pad is manufactured and the process is very simple. d) Alternate Material Disc The alternate material that can be used is Carbon Ceramic rotors. Carbon ceramics rotors were into application in high performance cars because it called in for high performance.CC rotors are very heat resistant and much more durable than cast iron brake. Advantages of Ceramic Brakes over Cast iron Carbon Ceramic s rotors have more frictional force which helps in stopping the car quickly. They dissipate heat quickly which helps reduce brake fade which is the loss of friction at high temperature Since the heat buildup is lesser, the wear and tear is also reduced The overall weight of the rotors are reduced which help in reducing the weight of the car especially the unsprung mass which helps in handling. CC rotors can withstand 2.5 times the heat steel can withstand which enables it to work in extreme heat. Ceramics have found their place in most of the high performance cars. Ceramics are still under the development stage. Disadvantages of Ceramic Brakes over Cast Iron CC rotors are limited to open wheel configuration because of the high temperature generated. The major disadvantage is the low coefficient of friction in wet or damp condition. CC rotors phenomenally expensive They cannot be repaired if cracked or damaged The production process is very complicated too. Ceramic Rotors are perfect selection for sports car and high performance cars but they seem to be inefficient for normal passenger cars. There are many researches going on in ceramics as they seem to give the best of all the worlds. The potential for ceramics are immense in automotive industry. They are widely used in aerospace now. The manufacturing process is also being refined which are moderating the cost which enables ceramics in a wider driving spectrum.CC rotors help reduce the weight of the vehicle as it is 4 times lighter than cast iron which increases fuel efficiency and help reduce the unsprung mass of the vehicles which gives better handling.CC rotors are made from a carbon reinforcement impregnated with a carbon matrix which is subjected to long and expensive process. There is new ceramics under development and this field is expanding. Caliper The alternate material used in caliper is aluminum. Aluminum is a very light material and can be cast without much expense. Aluminum is used because it is light weight, stiff and non corrosive. Advantages Light weight material comparing to cast iron which helps reduce the upsprung mass of car It can be manufactured easily and tooling is inexpensive. It can be anodized for better look and protection Stiff material and gives sufficient strength Non corrosive and is not affected by water under most conditions. Disadvantages over cast iron Material not strong enough and have lesser compressive and tensile strength. Aluminum has low damping and doesnt absorb vibrations More expensive than cast iron, more manufacturing process Poor ability to transfer heat, aluminum is a poor thermal insulator. Aluminum is widely used to make calipers in modern cars due to its properties and charactertics. More research is being carried out to make aluminum stiffer and harder. Many new aluminum alloys are being produced and tested. Aluminum calipers are larger in size when compared to cast iron calipers; this is due to the fact that the required stiffness is reached only within a certain size. The pistons used in the caliper vary from steel to titanium. The caliper needs good surfaces finish and should also take high stress and shape. Aluminum delivers all the required design specification and making aluminum the best alternate material to be used in calipers. Pads As the increasing rate of technology, brake pads have improved over the years. Asbestos were replaced by semi metallic and now replaced by ceramic pads. Asbestos pad caused health issues and semi metallic pad were noisy and eroded the rotors. Ceramic brakes have been selected as the alternate material for brake pads. Advantages The major advantage is low dust formed when braking. Improved braking over semi metallic and asbestos Stable and even friction available at all temperature range Extremely quiet performance and provide comfort to the passenger The pad life has also been extended also the rotor life as the pads dont erode the rotors. Disadvantages The only disadvantage till now is the rather expensiveness of the brake pads, but with constant manufacturing up gradation, the prices will come down. Ceramic brake pads are found to be an ultimate product, but research is continuing in the process of making it more efficient and cheaper. The dusts produced by ceramics are minimal and are not noticeable making the disc more cleanly in appearance. The ceramic pads are made up of a carbon-ceramic mostly with carbon fibers within silicon carbide matrix(C/SiC).This gives all the qualities to the brake pads according to the design requirement. e) Manufacturing Route for Alternate material Disc The manufacturing process of a ceramic disc rotor is complex and involves a number of steps. Rotors are expensive because of the expensive manufacturing process. The process starts with the preparation and arrangement of multiple layers of fiber fabric. Forming a material in with all the properties involves complex manufacturing process and the properties depend on the selection and densification process. The fibers are taken and heated to a point where they dont melt or burn. Fiber arrangement range from random chopped mat to woven fabric. Then the fiber material is formed in mould to produce the disc shape and then heated to eliminate non carbon elements. After this a process known as chemical vapor deposition (CVD) is used. In CVD porous product is heated in vacuum and then hydrocarbon gas is supplied in to diffuse all the cracks. In isothermal CVD, densification occurs at uniform temperature. Once the specific density and porosity is obtained, the disc is taken out and mach ined, drilled and treated with an antioxidant or special paint for protection. The process is a very length one and takes about 30 to 40 days. The manufacturing process increases the cost of the brakes. Research is being done to reduce the process while maintaining the property of the ceramic disc rotors. Caliper The manufacturing process used to make calipers out aluminum is Gravity Die Casting (GDC).This is different from High pressure die casting used for cast iron. This involves pouring the liquid gently into a reusable metal die. In this process the cores make the difference, the cavity formed due to the cores help the movement of liquid through the core. It includes two cores where one is moveable. The liquid is poured into the die and due to gravity it flows to the cavity and fills the gaps. Once it is solid and set, the die is removed and the finished is removed. After that it is machined to give it a surface finish. The main advantage of gravity die casting over sand casting is the production speed. The same die can be used for hundreds of casting. This process also gives a dimensional accuracy and surface finish. This process is widely used in cast aluminum alloy calipers. Pad Ceramic brake pads are manufactured similar to the cast iron brake pads. The ceramic material is cut into the shape and another metal piece is taken and the both are cold pressed into green compact. Sintering is carried out in vacuum where the organic binding agent concentrations get pyrolized and the metal particles bonded by reaction to carbon. Several binding agents are suited for pyrolysis.eg silicon carbide. One side of the pad will have the friction material and the other will have the support. Thus the manufacturing process for brake pad for alternate material uses expensive materials and process making it more expensive than conventional brake pads.

A Risk Neutral Framework For The Pricing Of Credit Derivatives :: Business Finance Essays

A Risk Neutral Framework For The Pricing Of Credit Derivatives 1. INTRODUCTION Considerable research effort has gone into Credit Derivatives since the early 1990’s. The roots of credit derivatives can be traced back to the notion that the credit risk of a firm can be captured by the credit rating ascribed to it. This premise is also the cornerstone of loan pricing and credit risk management models the world over, including J.P. Morgan’s CreditMetricsTM. Empirical research enables the predictability of the event of default as well as the Loss in the Event of Default (LIED). This information is expressed in terms of a ‘transition matrix’ - a matrix that traces out the probabilities the migration of a firm’s credit rating. Rating agencies such as Standard & Poor (S&P) provide transition matrices computed from periods of data about bonds - default record and post-default behaviour in the US markets. Lack of adequate data precludes the computation of such matrices in the Indian context, although it is possible to map ratings of Indian rating agencies such as CRISIL onto S&P ratings. 2. TYPES OF CREDIT DERIVATIVES Here is a brief description of some popular types of credit derivatives: 2.1 Credit Default Swaps A credit default swap provides a hedge against default on some payment, such as a bond. The counterparty buying credit protection pays the provider a certain amount in return for a guarantee to make good the loss in the event of default. 2.2 Total Return Swaps In this contract, the ‘payer’ gives a ‘receiver’ the total return on an asset in return for the returns on a benchmark asset, typically a risk-free asset. The payer has thus eliminated the risk of default in return for a lower but certain risk-free rate of return. 2.3 Credit Spread Derivatives Credit spread derivatives take the form of credit spread options, forwards or swaps. A credit spread call option, for example, is a call option written on the level of the spreads for a given bond. The option, thus increases in value as the spread increases, so that the value of the bond is protected. 3. RISK-NEUTRALITY Hypothesising the existence of a ‘risk-neutral’ world is extremely useful in the pricing of instruments whose value is derived from a stochastic process. In the real world, the present price is less than the expected net present value of the likely outcomes in future. Thus, for example, if the price of a commodity can become either Rs.

Heideggers Interpretation of Pablo Picassos Portrait of Gertrude Stein :: Art Artisits

Heidegger's interpretation of Pablo Picasso's Portrait of Gertrude Stein By several accounts, Gertrude Stein posed for Pablo Picasso more than 90 times during the winter of 1905-6. Each session was never quite correct, with many botched attempts and frustrations. Ultimately Picasso sent her away, stating "I can't see you any longer when I look," then created a new portrait of her nearly a year later without seeing her again. It was regarded as a curious mask-like visage, not really an accurate representation of Stein at the time. When others remarked that Gertrude Stein did not look like her portrait, Picasso stated "She will." Eventually Picasso's belief in the 'premonitory powers' of his portraits was affirmed as Stein came to very greatly resemble her portrait, stating in 1938, "I was and I still am satisfied with my portrait; for me, it is I, and it is the only reproduction of me which is always I, for me" (Rodenbeck). Picasso's Portrait of Gertrude Stein is a haunting and pensive work, imbued with a great sense of mystery and pondering. Stein's gaze is cast to the side, her hands in a gestural position, leaning forward with her chin tilted and lips slightly parted. It is as if she is about to speak and through the body language of her portrait, we envision an ensuing scene where she articulates what she's been thinking, elaborating with her hands. The essence of Stein's character is embodied in this posture and gesture, the truth of her being in this physical representation. Knowing nothing of Stein, one would at once understand that this woman is a thinker carefully considering her points and that this intellectual characterization is of fundamental importance to her mode of being. Picasso has achieved the revelatory effects in this portrait by revealing the truth of Stein through Martin Heidegger's principle of truth as aletheia, that is, unhiddenness or the experience of something hidden being brought to revelation. By not allowing Stein's thoughts and words to be heard and capturing her in a frozen moment of paint, Picasso allows a profound understanding of all that she has to say. By concealing the experience of being in her presence and knowing her as an intellectual, he reveals the very truth and nature of her composure and existence. Were this portrait a frozen monument of Stein in a moment of glory, a pristine tribute to her physicality or a photographic and perfect representation, then we could never see the true accuracy of her being and becoming.

The Portrayal of War in Charge of the Light Brigade and Dulce et Decoru

The Portrayal of War in Charge of the Light Brigade and Dulce et Decorum Est Both "Charge of the Light Brigade" by Alfred Lord Tennyson and "Dulce et Decorum est" by Wilfred Owen are poems about war. However, they were written in two very different contexts and about two very different wars. Charge of the Light Brigade describes a doomed cavalry charge made by British soldiers during The Battle of Balaclava in the Crimean War (1854-1857). Dulce et Decorum est, on the other hand, tells the story of a group of soldiers who were caught in a gas attack returning from the trenches of World War I (1914-1918) towards their "distant rest". Alfred Lord Tennyson was the "Poet Laureate" at that time and wrote the poem after reading about The Battle of Balaclava in the "Times" newspaper. This could have influenced how he portrayed the battle as he used secondary information which could be unreliable. In contrast, Wilfred Owen had first hand battle experiences from World war I, and so you would expect his information to be more reliable, However he could have emphasised certain points for poetic effect. In Dulce et Decorum est Wilfred Owen uses a variety of similes metaphors and other poetic techniques to describe the actions, appearance and mental states of the soldiers. Owen describes the soldiers as "Bent double, like old beggars under sacks, knock-kneed, coughing like hags", this simile shows that the war has had a very large effect on the soldiers as it gives the impression that they have aged prematurely and are in a very bad state of health. Owen also says that they limped on "blood-shod, all went lame, all blind", also giving the impression that the soldiers are in a very bad state of health, this emphasi... ...rge of the Light Brigade Tennyson gives the impression that the British soldiers were fighting a loosing battle. Tennyson gives the impression to the reader that he is not against the war even if they were going to loose but he still praises the soldiers for what they did. In Charge of the Light Brigade Tennyson contradicts Owens views, and instead says that it is honourable to die for ones country even if you loose the battle. In general I prefer Dulce et Decorum est because of what the poem stands for, Dulce et Decorum est give the views that war is a terrible thing and Owen is very against it whereas Tennyson seems to be a lot more pro war. Works Cited L. Bensel-Meyers. Literary Culture: Reading and Writing Literary Arguments. New York: Pearson Custom P,2000. Napierkowski, Marie Rose and Mary K Ruby. â€Å"Poetry for Students.† Vol 1 Detroit: 1998.

The Twilight Saga 4: Breaking Dawn 26. Shiny

â€Å"I don't know how much we should tell Renee about this,† Charlie said, hesitating with one foot out the door. He stretched, and then his stomach growled. I nodded. â€Å"I know, i don't want to freak her out. Better to protect her. This stuff isn't for the fainthearted.† His lips twisted up to the side ruefully. â€Å"I would have tried to protect you, too, if I'd known how. But I guess you've never fit into the fainthearted category, have you?† I smiled back, pulling a blazing breath in through my teeth. Charlie patted his stomach absently. â€Å"I'll think of something. We've got time to discuss this, right?† â€Å"Right,† I promised him. It had been a long day in some ways, and so short in others. Charlie was late for dinner – Sue Clearwater was cooking for him and Billy. That was going to be an awkward evening, but at least he'd be eating real food; I was glad someone was trying to keep him from starving due to his lack of cooking ability. All day the tension had made the minutes pass slowly; Charlie had never relaxed the stiff set of his shoulders. But he'd been in no hurry to leave, either. He'd watched two whole games – thankfully so absorbed in his thoughts that he was totally oblivious to Emmett's suggestive jokes that got more pointed and less football-related with each aside – and the after-game commentaries, and then the news, not moving until Seth had reminded him of the time. â€Å"You gonna stand Billy and my mom up, Charlie? C'mon. Bella and Nessie'll be here tomorrow. Let's get some grub, eh?† It had been clear in Charlie's eyes that he hadn't trusted Seth's assessment, but he'd let Seth lead the way out. The doubt was still there as he paused now. The clouds were thinning, the rain gone. The sun might even make an appearance just in time to set. â€Å"Jake says you guys were going to take off on me,† he muttered to me now. â€Å"I didn't want to do that if there was any way at all around it. That's why we're still here.† â€Å"He said you could stay for a while, but only if I'm tough enough, and if I can keep my mouth shut.† â€Å"Yes†¦ but I can't promise that we'll never leave, Dad. It's pretty complicated___† â€Å"Need to know,† he reminded me. â€Å"Right.† â€Å"You'll visit, though, if you have to go?† â€Å"I promise, Dad. Now that you know/usf enough, I think this can work. I'll keep as close as you want.† He chewed on his lip for half a second, then leaned slowly toward me with his arms cautiously extended. I shifted Renesmee – napping now – to my left arm, locked my teeth, held my breath, and wrapped my right arm very lightly around his warm, soft waist. â€Å"Keep real close, Bells,† he mumbled. â€Å"Real close.† â€Å"Love you, Dad,† I whispered through my teeth. He shivered and pulled away. I dropped my arm. â€Å"Love you, too, kid. Whatever else has changed, that hasn't.† He touched one finger to Renesmee's pink cheek. â€Å"She sure looks a lot like you.† I kept my expression casual, though I felt anything but. â€Å"More like Edward, I think.† I hesitated, and then added, â€Å"She has your curls.† Charlie started, then snorted. â€Å"Huh. Guess she does. Huh. Grandpa.† He shook his head doubtfully. â€Å"Do I ever get to hold her?† I blinked in shock and then composed myself. After considering for a half second and judging Renesmee's appearance – she looked completely out – I decided that I might as well push my luck to the limit, since things were going so well today___ â€Å"Here,† I said, holding her out to him. He automatically made an awkward cradle with his arms, and I tucked Renesmee into it. His skin wasn't quite as hot as hers, but it made my throat tickle to feel the warmth flowing under the thin membrane. Where my white skin brushed him it left goose bumps. I wasn't sure if this was a reaction to my new temperature or totally psychological. Charlie grunted quietly as he felt her weight. â€Å"She's†¦ sturdy.† I frowned. She felt feather-light to me. Maybe my measure was off. â€Å"Sturdy is good,† Charlie said, seeing my expression. Then he muttered to himself, â€Å"She'll need to be tough, surrounded by all this craziness.† He bounced his arms gently, swaying a little from side to side. â€Å"Prettiest baby I ever saw, including you, kid. Sorry, but it's true.† â€Å"I know it is.† â€Å"Pretty baby,† he said again, but it was closer to a coo this time. I could see it in his face – I could watch it growing there. Charlie was just as helpless against her magic as the rest of us. Two seconds in his arms, and already she owned him. â€Å"Can I come back tomorrow?† â€Å"Sure, Dad. Of course. We'll be here.† â€Å"You'd better be,† he said sternly, but his face was soft, still gazing at Renesmee. â€Å"See you tomorrow, Nessie.† â€Å"Not you, too!† â€Å"Huh?† â€Å"Her name is Renesmee. Like Renee and Esme, put together. No variations.† I struggled to calm myself without the deep breath this time. â€Å"Do you want to hear her middle name?† â€Å"Sure.† â€Å"Carlie. With a C. Like Carlisle and Charlie put together.† Charlie's eye-creasing grin lit up his face, taking me off guard. â€Å"Thanks, Bells.† â€Å"Thank you, Dad. So much has changed so quickly. My head hasn't stopped spinning. If I didn't have you now, I don't know how I'd keep my grip on – on reality.† I'd been about to say my grip on who I was. That was probably more than he needed. Charlie's stomach growled. â€Å"Go eat, Dad. We will be here.† I remembered how it felt, that first uncomfortable immersion in fantasy – the sensation that everything would disappear in the light of the rising sun. Charlie nodded and then reluctantly returned Renesmee to me. He glanced past me into the house; his eyes were a little wild for a minute as he stared around the big bright room. Everyone was still there, besides Jacob, who I could hear raiding the refrigerator in the kitchen; Alice was lounging on the bottom step of the staircase with Jasper's head in her lap; Carlisle had his head bent over a fat book in his lap; Esme was humming to herself, sketching on a notepad, while Rosalie and Emmett laid out the foundation for a monumental house of cards under the stairs; Edward had drifted to his piano and was playing very softly to himself. There was no evidence that the day was coming to a close, that it might be time to eat or shift activities in preparation for evening. Something intangible had changed in the atmosphere. The Cullens weren't trying as hard as they usually did – the human charade had slipped ever so slightly, enough for Charlie to feel the difference. He shuddered, shook his head, and sighed. â€Å"See you tomorrow, Bella.† He frowned and then added, â€Å"I mean, it's not like you don't look†¦ good. I'll get used to it.† â€Å"Thanks, Dad.† Charlie nodded and walked thoughtfully toward his car. I watched him drive away; it wasn't until I heard his tires hit the freeway that I realized I'd done it. I'd actually made it through the whole day without hurting Charlie. All by myself. I must have a superpower! It seemed too good to be true. Could I really have both my new family and some of my old as well? And I'd thought that yesterday had been perfect. â€Å"Wow,† I whispered. I blinked and felt the third set of contact lenses disintegrate. The sound of the piano cut off, and Edward's arms were around my waist, his chin resting on my shoulder. â€Å"You took the word right out of my mouth.† â€Å"Edward, i did it!† â€Å"You did. You were unbelievable. All that worrying over being a newborn, and then you skip it altogether.'7He laughed quietly. â€Å"I'm not even sure she's really a vampire, let alone a newborn,† Emmett called from under the stairs. â€Å"She's too tame.† All the embarrassing comments he'd made in front of my father sounded in my ears again, and it was probably a good thing I was holding Renesmee. Unable to help my reaction entirely, I snarled under my breath. â€Å"Oooo, scary,† Emmett laughed. I hissed, and Renesmee stirred in my arms. She blinked a few times, then looked around, her expression confused. She sniffed, then reached for my face. â€Å"Charlie will be back tomorrow,† I assured her. â€Å"Excellent,† Emmett said. Rosalie laughed with him this time. â€Å"Not brilliant, Emmett,† Edward said scornfully, holding out his hands to take Renesmee from me. He winked when I hesitated, and so, a little confused, I gave her to him. â€Å"What do you mean?† Emmett demanded. â€Å"It's a little dense, don't you think, to antagonize the strongest vampire in the house?† Emmett threw his head back and snorted. â€Å"Please!† â€Å"Bella,† Edward murmured to me while Emmett listened closely, â€Å"do you remember a few months ago, I asked you to do me a favor once you were immortal?† That rang a dim bell. I sifted through the blurry human conversations. After a moment, I remembered and I gasped, â€Å"Oh!† Alice trilled a long, pealing laugh. Jacob poked his head around the corner, his mouth stuffed with food. â€Å"What?† Emmett growled. â€Å"Really?† I asked Edward. â€Å"Trust me,† he said. I took a deep breath. â€Å"Emmett, how do you feel about a little bet?† He was on his feet at once. â€Å"Awesome. Bring it.† I bit my lip for a second. He was just so huge. â€Å"Unless you're too afraid†¦ ?† Emmett suggested. I squared my shoulders. â€Å"You. Me. Arm-wrestling. Dining room table. Now.† Emmett's grin stretched across his face. â€Å"Er, Bella,† Alice said quickly, â€Å"I think Esme is fairly fond of that table. It's an antique.† â€Å"Thanks,† Esme mouthed at her. â€Å"No problem,† Emmett said with a gleaming smile. â€Å"Right this way, Bella.† I followed him out the back, toward the garage; I could hear all the others trailing behind. There was a largish granite boulder standing up out of a tumble of rocks near the river, obviously Emmett's goal. Though the big rock was a little rounded and irregular, it would do the job. Emmett placed his elbow on the rock and waved me forward. I was nervous again as I watched the thick muscles in Emmett's arm roll, but I kept my face smooth. Edward had promised I would be stronger than anyone for a while. He seemed very confident about this, and I felt strong. That strong? I wondered, looking at Emmett's biceps. I wasn't even two days old, though, and that ought to count for something. Unless nothing was normal about me. Maybe I wasn't as strong as a normal newborn. Maybe that's why control was so easy for me. I tried to look unconcerned as I set my elbow against the stone. â€Å"Okay, Emmett. I win, and you cannot say one more word about my sex life to anyone, not even Rose. No allusions, no innuendos – no nothing.† His eyes narrowed. â€Å"Deal. I win, and it's going to get a lot worse.† He heard my breath stop and grinned evilly. There was no hint of bluff in his eyes. â€Å"You gonna back down so easy, little sister?† Emmett taunted. â€Å"Not much wild about you, is there? I bet that cottage doesn't have a scratch.† He laughed. â€Å"Did Edward tell you how many houses Rose and I smashed?† I gritted my teeth and grabbed his big hand. â€Å"One, two – â€Å" â€Å"Three,† he grunted, and shoved against my hand. Nothing happened. Oh, I could feel the force he was exerting. My new mind seemed pretty good at all kinds of calculations, and so I could tell that if he wasn't meeting any resistance, his hand would have pounded right through the rock without difficulty. The pressure increased, and I wondered randomly if a cement truck doing forty miles an hour down a sharp decline would have similar power. Fifty miles an hour? Sixty? Probably more. It wasn't enough to move me. His hand shoved against mine with crushing force, but it wasn't unpleasant. It felt kind of good in a weird way. I'd been so very careful since the last time I woke up, trying so hard not to break things. It was a strange relief to use my muscles. To let the strength flow rather than struggling to restrain it. Emmett grunted; his forehead creased and his whole body strained in one rigid line toward the obstacle of my unmoving hand. I let him sweat – figuratively – for a moment while I enjoyed the sensation of the crazy force running through my arm. A few seconds, though, and I was a little bored with it. I flexed; Emmett lost an inch. I laughed. Emmett snarled harshly through his teeth. â€Å"Just keep your mouth shut,† I reminded him, and then I smashed his hand into the boulder. A deafening crack echoed off the trees. The rock shuddered, and a piece – about an eighth of the mass – broke off at an invisible fault line and crashed to the ground. It fell on Emmett's foot, and I snickered. I could hear Jacob's and Edward's muffled laughter. Emmett kicked the rock fragment across the river. It sliced a young maple in half before thudding into the base of a big fir, which swayed and then fell into another tree. â€Å"Rematch. Tomorrow.† â€Å"It's not going to wear off that fast,† I told him. â€Å"Maybe you ought to give it a month.† Emmett growled, flashing his teeth. â€Å"Tomorrow.† â€Å"Hey, whatever makes you happy, big brother.† As he turned to stalk away, Emmett punched the granite, shattering off an avalanche of shards and powder. It was kind of neat, in a childish way. Fascinated by the undeniable proof that I was stronger than the strongest vampire I'd ever known, I placed my hand, fingers spread wide, against the rock. Then I dug my fingers slowly into the stone, crushing rather than digging; the consistency reminded me of hard cheese. I ended up with a handful of gravel. â€Å"Cool,† I mumbled. With a grin stretching my face, I whirled in a sudden circle and karate-chopped the rock with the side of my hand. The stone shrieked and groaned and – with a big poof of dust – split in two. I started giggling. I didn't pay much attention to the chuckles behind me while I punched and kicked the rest of the boulder into fragments. I was having too much fun, snickering away the whole time. It wasn't until I heard a new little giggle, a high-pitched peal of bells, that I turned away from my silly game. â€Å"Did she just laugh?† Everyone was staring at Renesmee with the same dumbstruck expression that must have been on my face. â€Å"Yes,† Edward said. â€Å"Who wasnt laughing?† Jake muttered, rolling his eyes. â€Å"Tell me you didn't let go a bit on your first run, dog,† Edward teased, no antagonism in his voice at all. â€Å"That's different,† Jacob said, and I watched in surprise as he mock-punched Edward's shoulder. â€Å"Bella's supposed to be a grown-up. Married and a mom and all that. Shouldn't there be more dignity?† Renesmee frowned, and touched Edward's face. â€Å"What does she want?† I asked. â€Å"Less dignity,† Edward said with a grin. â€Å"She was having almost as much fun watching you enjoy yourself as I was.† â€Å"Am I funny?† I asked Renesmee, darting back and reaching for her at the same time that she reached for me. I took her out of Edward's arms and offered her the shard of rock in my hand. â€Å"You want to try?† She smiled her glittering smile and took the stone in both hands. She squeezed, a little dent forming between her eyebrows as she concentrated. There was a tiny grinding sound, and a bit of dust. She frowned, and held the chunk up to me. Til get it,† I said, pinching the stone into sand. She clapped and laughed; the delicious sound of it made us all join in. The sun suddenly burst through the clouds, shooting long beams of ruby and gold across the ten of us, and I was immediately lost in the beauty of my skin in the light of the sunset. Dazed by it. Renesmee stroked the smooth diamond-bright facets, then laid her arm next to mine. Her skin had just a faint luminosity, subtle and mysterious. Nothing that would keep her inside on a sunny day like my glowing sparkle. She touched my face, thinking of the difference and feeling disgruntled. â€Å"You're the prettiest,† I assured her. Tm not sure I can agree to that,† Edward said, and when I turned to answer him, the sunlight on his face stunned me into silence. Jacob had his hand in front of his face, pretending to shield his eyes from the glare. â€Å"Freaky Bella,† he commented. â€Å"What an amazing creature she is,† Edward murmured, almost in agreement, as if Jacob's comment was meant as a compliment. He was both dazzling and dazzled. It was a strange feeling – not surprising, I supposed, since everything felt strange now – this being a natural at something. As a human, I'd never been best at anything. I was okay at dealing with Renee, but probably lots of people could have done better; Phil seemed to be holding his own. I was a good student, but never the top of the class. Obviously, I could be counted out of anything athletic. Not artistic or musical, no particular talents to brag of. Nobody ever gave away a trophy for reading books. After eighteen years of mediocrity, I was pretty used to being average. I realized now that I'd long ago given up any aspirations of shining at anything. I just did the best with what I had, never quite fitting into my world. So this was really different. I was amazing now – to them and to myself. It was like I had been born to be a vampire. The idea made me want to laugh, but it also made me want to sing. I had found my true place in the world, the place I fit, the place I shined.