INTRODUCTION
1.1 Introduction
In designing a railway wheel, the important thing that must be considered is material used. Choosing the right material will give a better result to the performance and the condition of the wheel. It is believed that most of the problems that occur to the railway wheel are the result from the thread braking, which is known as non-uniform heating. Thermal loading has the ability to initiate cracks, increase the crack growth rate and also reverse the residual stress in the rim. For the railway operation, there are two types of braking that involves in the operation which are stop braking and drag braking. Stop braking is used during the emergency time. Another one is drag braking, used to slow the train over a long distance, to ensure that the speed is under the control. In stop braking condition, thermal fatigue cracks will initiate and propagate while under the drag braking condition, an extreme thermal input occurs which can fracture the wheel. When the brakes are applied for long periods of time, it will cause the heating of the thread and rim of the wheel, generated by frictional forces. Observation of the railway wheel has been made based on the wheels in Keretapi Tanah Melayu (KTM) Padang Besar, found that there is no crack occur except the scratch. This also happens due to the braking. Aside from friction heat result from the brake application, crack may also initiate and propagate due to the impact load that has been applied to the wheel. For each of different size of wheels, there is limitation for the load. It is important to understand the basic modes of fracture that are enable a crack to propagate. The three modes are opening mode (mode I), in-plane-shear (mode II) and out-of-plane-shea...
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...s for both wheels appear to be similar for equivalent orientation and location. For both of the cast and forged wheels, Paris slope was higher for circumferential crack growth in the rim and radial crack growth in the web. Based on the tests made, higher levels of crack were exhibited in the cast material, particularly in the threshold regime. The apparent resistance to fatigue crack growth appeared to be same in those two materials. S.Tarefder et al. were used J-integral parameter to determine the fracture toughness of the cast and forged wheel materials. Elastic plastic fracture mechanics (EPFM) were used since the elastic plastic frature mechanics (LEFM) based fracture toughness could not be validated for both material involved. S.Tarafder et al. concluded that the forged wheel material showed a better fracture toughness in comparison to the cast wheel material.
George Washington Gale Ferris Jr.(14 Feb. 1859-22 Nov. 1896) was a civil engineer/ construction engineer who invented the Ferris Wheel. George Ferris was born in Galesburg, Illinois to farmers, George Washington Gale Ferris Sr. and Martha Edgerton Hyde Ferris. He lived with his 4 sisters and 2 brothers. When Ferris 5 years old his family sold their farm and headed toward San Jose, California. Unfortunately in the middle of their journey they ran out of money and had to settle in Carson City. In Carson City they made a ranch and Ferris helped his father farm for 9 years before going to California Military Academy in 1873. In 1876 he graduated and applied for the Rensselaer Polytechnic Institute in Troy, New York to study civil engineering.
Because of the job opportunities in the West that were advertised throughout the World , many people who found themselves out of place after being freed, or having their livelihood freed, sought to take up shop and make their way to these new opportunities.
The Duluth Model System incorporated a multi-disciplinary team of police officers, probation officers, prosecutors, and human services that undertook domestic abuse cases. It also put the responsibility on helping professionals such as social workers, psychologists, and doctors. Their job was to not only advocate for victims of abuse, but to respond to victims in a loving and non-biased manner. The primary objective to having a complete community response was to prevent victims from further abuse (Shephard & Pence, 1999). Moreover, judges were advised to prosecute victims more fairly by looking at their cases with a holistic approach.
Fatigue failure can be divided in three parts i.e. Crack initiation, Crack propagation and Final rupture.
The Transcontinental railroad could be defined as the most monumental change in America in the 19th century. The railroad played a significant role in westward expansion and on the growth and development of the American economy (Gillon p.653). However, the construction of the transcontinental railroad may not have occurred if not for the generous support of the federal government. The federal government provided land grants and financial subsidies to railroad companies to ensure the construction. The transcontinental railroad contributed to the formation of industry and the market economy in America and forever altered the American lifestyle.
The important thing to know about an object that is moving on wheels is that its kinetic energy is equal to half of its mass including the wheels(Mb) multiplied by the square of its velocity(V) plus the kinetic energy in the rotating wheels. In this case I am going to assume that all of the mass of the wheels is located on the outer edge (this isn't really the case, but most of the mass is there). Then the kinetic energy of a wheel due to rotation is half of its mass(Mw) multiplied by the square of its radius(r) multiplied by the square of its angular velocity(w) multiplied by two since there are two wheels.
The world of Model Train Building has grown greatly with the aid of computers and technology to enhance the fun of building. Technology has long been a part of Model Train building with the adding of lights, bells, and whistles to capture your interest and imagination. But with the latest generation of building comes the influx of technology and the computer. The computer brings along a new breed of builders who plan track layout, buy parts on the Internet, receive updated news, and chat with other enthusiast.
At the beginning of the industrial revolution in England during the mid-nineteenth century, the railroad was the most innovative mode of transportation known. The British Rail system was a forerunner in railroad technology, uses, and underground engineering. Though the rail system was extremely slow at first and prohibitively expensive to build and run, the British were not to be dissuaded in their pursuit of non-animal driven transportation. The most advanced mode of transportation prior to the introduction of the rail system was the horse drawn omnibus on a track, called a tram. This paper will examine the rail system from a cultural perspective, presenting the impact the railway had on everyday lives in Victorian London and its surrounding communities.
In Aboriginal teachings, the medicine wheel is sacred because it represents the various components of a healthy, well-rounded individual. Like wellness, the medicine wheel represents an “active state of health in which an individual progresses toward a higher level of functioning, thus achieving an optimum balance” (as cited in Fain & Lewis, 2002, p. 7). The medicine wheel is divided into four major sections, each representing a major part of a person (physical, emotional, mental, and spiritual). In order to achieve balance in one’s life, one must analyze each of these components, and work to improve communications within one’s self. Intrapersonal communication is vital to the development of self-concept and self-esteem, which in turn, contribute to better communication and interpersonal relationships (Beebe, Beebe, Redmond, & Geerinck, 2008). Therefore, it is crucial that a person has a “genuine sense of worth [in themselves],” before they look to develop an understanding of another person’s life (social decentering) (Beebe et al., 2008, p.47). This paper will serve as a means to assess my own intrapersonal communication in each of these four categories, using the medicine wheel described in Mussell (2005). In doing so, I hope to gain insight of how to improve my intrapersonal communication in each aspect of my life, which will, in theory, contribute to an increased ability to communicate with others (interpersonal communication).
The main advantage of the track over the wheels is that it can distribute a very large force over a large area. That means that instead of applying all the force on little area where wheels touch the ground, it applies it over the whole area of the track.
slope. I think that out of all the variables, this is the one which is
The most common style of drive train is that of the front wheel drive, abbreviated FWD. Front wheel drive was not, however, the first drive system. Front wheel drive first made its appearance in the automobile market in 1933 with the French Traction Avant, which literally means "pull from the front." At the time, the idea of having a car pulled by the front wheels was rather different, but this style of getting the power to the wheels worked rather well. What made the Traction Avant successful was that it was lighter and more fuel efficient than other car models made at the time. This increased efficiency was a result of not only eliminated weight, but also reduced power loss in moving the rotational energy to the back.
The first brake system was used thousands of years ago. The Romans had a system that involved a wooden block and a lever to slow and stop the cart. The driver would push or pull the lever which causes a wooden block to be pressed against the outer part of the wheel. These were used until the 20th century. Later the drum and disc brakes were invented to accommodate the faster motorized automobiles. The drum brake is placed in the inner surface of the wheel. When the brake is applied, the brake shoes will move outward and create friction against the drum. In the disc brake, there are more components to it. There is a rotor that is attached to the wheel and a caliper. The rotor is a disc which rotates with the wheel. The caliper squeezes on the rotor when the brakes are pressed instead of rubbing directly against the wheel. Disc brakes are sometimes preferred to drum brakes because of its superior cooling system. When the brake pads rub against the rotor or drum, heat is also produced. It is harder for the drum brakes to cool down because it is located inside the wheel and not exposed to as much outside air. Some disc brakes will have slits on the sides of the disc to provide cooling. Faster cooling will pre...
From Ancient Mesopotamia came a revolutionary tool that has crystallized the world into the complex civilization it is today, the wheel. The wheel has commutated the very way we live and think about the world and all credit goes to Ancient Mesopotamia for providing this life changing invention. Wheels are everywhere we look and in places that you wouldn't even think. Wheels are used everyday in some way or another and come in many sizes and innumerable different materials and purposes. This prodigious invention has helped ancient Mesopotamians work, move, and live and still helps us today.
Rail transportation is a transportation in which for movement of people and goods which from one location to another destination. Rail had been takes the important role in physical and economic development of town and cities in a country and it was developed over the world. Rail transport can be made a property value in a country increase and it must be needs improvement in transportation network expanding (Goldberg, 1970). Thus, the railway services need to be done with continuous improvement and it is important to the rail passengers of the range and quality of facilities and service on stations and trains (Gleave, S. D., 2000). The future development to a public transportation is a key to affect