The Great San Francisco Earthquake

Introduction An earthquake is essentially a quiver which resulted by sudden energy release from the earth inner surface. The release of energy causes a ripple of seismic waves that are felt in the form of shaking. The damage caused by an earthquake depends on the magnitude and the length of such earthquake. (U.S. Geological Survey2008, April 22).Advertising We will write a custom essay sample on The Great San Francisco Earthquake specifically for you for only $16.05 $11/page Learn More The length however depends on the size of the wave since the larger the wave the larger the area affected and consequently the longer the period of time taken. Each year the earth experiences up to half a million-earth quakes of which only 100, 000 can be truly felt. The probability of occurrence of an earthquake depends on the nature of the locality as well as its geology. South California alone experiences up to 10000 earthquakes a year. History of earthquakes in San Fra ncisco Earliest reported earthquake in California was felt in 1769 the worst of them all was the 1906 San Francisco earthquake. There have been severel other smaller earth quakes that have hal minimal impact and even gone unnoticed. Others which have been of a greater impact Situational analysis and probability of an earthquake in the near future Research has predicted that there exsists a 25% probability of an earth quake with a magnitude of up to 7.0 occuring within the next two decades in sanfrancisco. Based on the historical data as well as computer simulations it has been suggested that there is an even more greater chance that an earthquake of an even greatter magnitude will occur in the next 45 years. The death toll is estimated at a shocking 5,800 deaths if the magnitude is at least 7.0. this means that the value could be higher if the ripple effect is of agreater magnitude(Abercrombie and Brune1994) Sanfrancisco notably lies on the san andreas fault which is considered the most vulnerable to such earth quakes. The last time such an event occured in 1989 it left 66 dead and 3,757 injured. It only lasted fifteen seconds but the damage to property was indisputably large with the San Francisco Oklahoma Bridge collapsing. This damage went to the tune of 6 billion in property damage. The then United States president George bush issued a 3.45 billion package that was to act as relief for the affected. The effect could have been even more grave had there been a tsunamic effect. This would have resulted in flooding of the coastal towns sweeping away their homes and destroying their productive farms. The earth quake would damage the regions leeves bearing an effect similar to that of harricane katrina.Advertising Looking for essay on government? Let's see if we can help you! Get your first paper with 15% OFF Learn More The damage would even be worse after the earth quake as the flood water contaminates the fresh water supply that is mainly supplie d though an over land aquaduct that would cost even more to repair. It is estimated that at least 24,000 homes were damaged and 100000 left homeless after the floods caused by snow melts hit sanfrancisco back in 1997. Up to 50 leeves were damaged (United States Geological Survey 1999, October 15) Even more compelling scientists from the United States geological survey suggest that there is a 70 % chance that at least one or more earthquakes with intensity not less than 6.7 will in the next 30 or so years strike San Francisco bay. This is equated to one that occurred in 1994, which left 57 people dead, and others wounded and caused destruction to the tune of $ 20 billion. (Seismological Society of America, 2008, April 17) General effects of an earthquake Earth quakes are categorized among the top ten most deadly natural disasters. They have the following effects Shaking and ground rupture -This is the single most probable effect of an earth quake. The intensity of the shaking will de pend heavily on the magnitude size as well as the distance from the epicenter. It will also depend on the geology of the area in question. Geological concerns go to the nature of the superficial soils in the subsurface of the earth. Landslides and avalanches -Landslides also bring along volcanic eruptions which may cause serious storms and wild fires. Landslides are specifically dangerous to both the affected and those who make attempts at providing rescue services. Fires –Â  Shaking causes damage to power lines and gas pipe systems which are a remedy to massive fires. The effects of these fires were typically felt in the 1906 San Francisco earth quake. The destruction by fire or any other human motivatied factor such as stampedes accidents and collusions would participate heavily to the increased casualties. These however will depend on the level of awareness of the poplation as well as the preparedness. Soil liquefaction –Â  This is a situation where sand and other granular material owing to the saturation of water temporarily loose strength and dissolve into liquid making the foundations upon which buildings and other rigid structures stand on to become loose causing the building to collapse or tilt. In the Alaskan earth quake the effects of soil liquefaction were immensely felt. This would however e an unlikelyeffect on sanfrancisco due to its geology.Advertising We will write a custom essay sample on The Great San Francisco Earthquake specifically for you for only $16.05 $11/page Learn More Tsunami – Tsunamis are often mistaken for tidal waves that rock the seas due to oceanic currents. The mechanism behind tsunamis is much more different. A tsunami is essentially caused by unusual sudden movement of water volumes in the open sea. The sudden movements could be caused by an earth quake in the submarine soils as well as landslides Floods -Earth quakes that occur in the open sea cause a tsunami effect that leads to seeping of water from the open sea and into the mainland causing floods. Sanfrancisco would be hardly hit by these floods due to its proximity to the sea.In the mainland they cause destruction of dams and water barriers leading to flooding. Human impacts -Earth quakes have a toll on every aspect of human life. They bring along a death toll besides the destruction caused to the infrastructure. They also cause disease owing to lack of necessities. Financially they lead to high claims for compensation besides the relief costs occurred in resettlement (The Virtual Museum of San Francisco, 2011). Emergency Planning Options. Citizen based approach This a proactive and reactive approach which involves two basic components; Leadership which involves appointment is disaster management managers who will be vetted based on willingness aggression and objectivity and partnership which involves embracing an integrated vision and mission and letting the community be part of the campaign The approach recommends the cooperation between government agencies and the people living in San Francisco. The government formulates a plan that requires the engagement of the people partially or as a whole. Government departments such as the police accept suggestions and receive volunteers who are trained and licensed as local disaster managers. The people are collectively involved in the The strategic approach The approach collects together all available resources and coordinates manages motivates the implementation of the awareness campaign. It encourages the building of an integrated programming system e.g., school based curriculum and emphasizes on capacity building and empowerment Strategy Implications The strategy adopted will among other things require the change of policy to accommodate the budgetary concerns of the implementation process. It will also require cooperation from all participants and interested parties including investors and development partners. The partner ship will help diversify the information platform and increase the level of awareness. The integration of the measures into the various programs such as the school-based curriculum will require training for the implementers who include teachers and administrators. (Interagency Coordinating Committee (ICC) 2008)Advertising Looking for essay on government? Let's see if we can help you! Get your first paper with 15% OFF Learn More Way forward With the objective of a better disaster management system the government should undertake in research to improve the understanding of the earthquake process its likelihood and impact. It should also develop cost efficient ways of combating the effects on individuals as well as improve the level of resilience in the population. There is a lot of information available in the various sources concerning the effects and consequences of an earthquake. Every citizen should develop a need to know to ensure that they make informed decisions in areas such as construction development and investment References Abercrombie, R.E., and J.N. Brune. (1994). Evidence for a constant b-value above magnitude 0 in the southern San Andreas, San Jacinto and San Miguel fault zones and at the Long Valley caldera. California. Geophys. Res. Lett., 21 (15), 1647-1650. Interagency Coordinating Committee (ICC).(2008). Strategic Planfor the National Earthquake Hazards Reduction Program Fiscal Years 200 9–2013. Web. Seismological Society of America. (2008, April 17). New Hazard Estimates Could Downplay Earthquake Dangers. ScienceDaily. Web. The Virtual Museum of San Francisco. (2011). San Francisco Earthquake History 1915-1989. Web. U.S. Geological Survey (2008, April 15). California Has More Than 99% Chance Of A Big Earthquake WIthin 30 Years, Report Shows. ScienceDaily. Web. U.S. Geological Survey. (2008, April 22). Earthquake Hazard Maps Show How U.S. Shakes With Quakes. ScienceDaily. Web. United States Geological Survey. (1999, October 15). 70 Percent Chance That Large Earthquake Will Strike San Francisco By 2030. ScienceDaily. Web. This essay on The Great San Francisco Earthquake was written and submitted by user Queen Noir to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.

Franchising

Franchising Introduction In the business world, there are many ways of getting into business. These entry areas vary depending on the type of the business. The interest of the businessperson is also a major factor. As such, many people wishing to get into business seek one of the many avenues that are open to them.Advertising We will write a custom essay sample on Franchising specifically for you for only $16.05 $11/page Learn More This includes business models such as sole proprietorship and business partnerships. A person can also enter into mergers or form a limited liability company among others. One of the most effective ways of getting into business is through franchising. There is a conclusive argument that this is one of the most effective ways of getting into business. In the corporate world today, getting into an entirely new business is very difficult due to the many entry inhibitors facing the corporate world. These include difficulties in raising the necess ary fees like business permits and the all-important capital. There are also many other statutory requirements. In case of a partnership, such requirements as articles of association or memorandum of association may be one of the requirements that the state demands to authenticate any entry into partnership (Michael and Hitt, 2010). In the case of a company, depending on whether it is Limited Liability Company or liability company, the entry requirement is a tiring task. So what is franchising? A franchise refers a privilege given to an individual or a group of people to be able to market or sell products or services of a certain enterprise within a certain location/locations. In other words, franchising means the rights granted to a person or a group of people by a certain company to use its name or trademark in marketing and distributing its goods and services. In the today’s corporate world, there are popular franchises. The most famous are the McDonalds, domino’s p izza, subway etc. Advantages of Franchising There are many types of franchising. They have come with their unique characteristics and this depends on their suitability to the franchising party. Their different types could be the reasons it has been argued that franchising is the most efficient and innovative form of business yet devised to distribute products and services.Advertising Looking for essay on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More Because of the success of the franchising form of business in the food industry, many people have come to associate franchising with only fast food like the MacDonald and the domino’s pizza. This is however not the case because a part from being a success in the fast food business, franchising has also been a success in other fields such as the finance automotive, cleaning and maintenance health etc. In the introduction of this paper, we began by conclusivel y saying that franchising is a major growth area for business and as such, the most efficient and innovative form of business yet devised to distribute products and services. In order for us to conclude this way, it is paramount about our reasoning that we look at how franchising work so that when we say that franchising is the major growth rate for business our utterance shall hold water. It is from understanding the working of franchise shall we then come to appreciate the advantages and disadvantages of franchising (Noora et al. 2005). In franchising, there are some important concepts that one has to understand. These are the franchisee and the franchisor. We ask ourselves, who are these? In clear terms, a franchisee is the individual who embarks on purchasing and consequently running a franchise. On the other hand, a franchisor is the person from whom the franchisee buys the franchise. In order for the franchise to work, there are always some rules and regulations that the franc hisee must adhere to. These in most of the time are the established rules of e.g. the company from whom the franchisee is buying the franchise (Scarborough, 2010).Advertising We will write a custom essay sample on Franchising specifically for you for only $16.05 $11/page Learn More In order for the franchisee to be fully been incorporated in the franchising company, payment of a certain fee called franchising royalty is necessary. In today’s corporate world, like mentioned earlier, franchising is one of the most fashionable ways of getting to do or enter into business. It is quite popular in the marketplace. From the 1850s when Isaac singer invented his sawing machines and started selling licenses to entrepreneurs to be able to distribute his machines to date when you cannot walk many blocks without coming across a franchise, we realize that franchising has come to revolutionize the business scene. It has come to help the individual entrepreneurs to be in business for themselves but actually not for themselves. The ideas behind being in a franchise rather than trying other forms of entry into business such as buy out or starting an entirely new business lies on the fact that in franchise there is always already proven business formula and structure that is in place. This therefore presents a high possibility of success for an individual opening a business than to the one who is getting into start up or other forms of business entry. This is further proven by the fact that in franchise, the products and services that one wants to deal with are already in the market and are already established.a good example of this is for a person wanting to get into pizza business.he can choose to buy a franchise from the domino’s pizza. His pizza business will perform well because the new entrant into the pizza business will meet an already established market (Beer, 1999).Advertising Looking for essay on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More This then saves the franchisee the problem of having to incur cost of introducing his products or services, cost that could include advertising and distribution. The reason as to why this form of business is revolutionary in the corporate world is that, the corporate image and the awareness of the bland of the company selling the franchise is already there. A new entrant in the market then does not make expenditures in trying to establish his new bland. This is because, the products or services are already known to the consumers, they continue purchasing the products or services since they are familiar with them. This is an evident advantage of franchising. It makes it appealing to franchise as they are saved the problem of convincing the consumers to buy their goods. A person wanting to get into hotel and hospitality industry may take years before establishing his industry. However, buying a franchise of established hotels like Day Inn and Supper 8 will prove beneficial in establis hing his hotel. (Christensen, 2006). Most of the franchisees are new entrants into the corporate world. In most of the time, they have little or no experience in running the business they are starting. In other cases, they are merely equipped with only the theory from the school. In such a case, franchising becomes a useful tool in gaining some knowledge about the business. This is because the franchisor in most of the time provides wide-range preparation and support to the franchisee. As such, this becomes a strategy beneficial to the franchisee since he is not faced with risks of making mistakes caused by doing guesswork in running the business. In clearly analyzing franchising as an effective way of getting into business, we realize that in franchising a lot of useful time is saved. This is because the business model and the franchise company already is in place and thus the time the individual in establishing the model of a new business is saved could use that. Because the franc hisee gets into an already existing company, he is in a position to concentrate in the successful running of the business. Starting an entirely new business offering financial services may prove difficult due to the many logistics involved. However, by choosing to buy a franchise from established firms like HR Block will help the new entrants in establishing his business. This is because such a firm is already established. Therefore, it has curved its niche among the customers (Zutshi, 2010). Because the franchise runs for a specific time and operates within a specific location, a franchisee can then aim at managing many of such locations. In franchising, the entry and exit becomes another advantage that makes this form of business be considered as a major growth area in business. Franchise can last from five to thirty years. One can then chose short franchise so that if it does not work the franchisee can then chose to exit into other forms of business. In addition to this, there a re no laws that demand the profitability of the franchisor be displayed. This however could at times be listed in the franchise disclosure document (FDD).but like said earlier it is not necessary. To a franchisee, this is an advantage because if the franchising company is not making profits, the franchisee can opt to quit from that franchise and seek for an alternative performing franchisor with little embarrassments. The franchisor offers national and international advertising. This too including other support services is provided to the new entrants into the business world. Franchise brokers offers services that come in handy to help the franchisee to seek the most appropriate franchise. Such a franchisee seeking to get into business can enlist the servicers of master franchisors who can then work to help the franchisee in obtaining rights to sub franchise in the location (Millmore, 2007). Franchising has been seen as the most effective and innovative form of business devised to d istribute products and service bases on the fact that franchising like explained here above is based on a proven idea. The franchisee is in a position to check and prove the success of The Company before committing resources. In so doing, the franchisee can compare between different franchisors and then chose the best according to his interests. The availability of established and recognized brand names makes his entry into business easier. As opposed to businesses such as start ups, buying a franchise proves to be helpful to the franchisee as he can enjoy the protected reputation of the franchisor. This legal and procedural protection includes legal departments set aside to handle legal issues such as lawsuits. It also takes care of difficulties with the employees. Having the protection of the franchisor is an important factor that can keep the franchisee surviving in the corporate world as with it come the positive expectations that keep the customers loyal to the products or the services offered by the franchisee. This benefit in addition to the already established body of legal protection is an important factor in the success of the new franchise (Bowles, 2011). Getting into start up for example may prove very challenging. Before a start up establishes enough to command recognition by the customers, it may take many years of continued effort in advertising. This problem is however solved by getting into franchise. In the today’s corporate world, people want a guarantee on the product and services they are purchasing. As such, recognition across the board (name, brand etc) gives the company assurance. This is exactly what the company might be looking for. Name recognition in the corporate world is very important because it creates the confidence in the customers such that they always know that they will always be assured of the product or services they are looking for. Franchising is aimed at risk minimization. To reduce this, the franchise investmen t enables the franchisees to thoroughly research on the franchisor before he commits any investment are made. The franchisee is able to acquire detailed information from other franchisees and this enables the franchisee to try on various businesses before purchases it. Concerning the risks mitigation efforts of a franchise, therefore, we find that franchising reduces the risks associated with business considerably. An example of this is getting in printing and postal services. This kind of business will require a lot of capital and knowledge on how to run the business. Committing resources to this kind of business without enough capital or information is a risky phenomenon. As such, buying franchise from firms like park mail will help save on such risks. Because of the group purchasing ability provided by a number franchises, franchisees are able to procure commodities and stores supply at a comparatively lesser cost from the franchisor. This too serves to make the argument that fra nchising is a major growth area for business. In franchising, a uniform system of operation is provided. The franchisee uses this factor to his advantage. As such, a uniform system of operation enables the consumers to acquire products and services of quality efficiently and at an effective cost. This in turn brings the benefit of growing the purchasing ability and the customer brand loyalty. It also brings brand identification among the potential markets. The franchisee capitalizes on this factor to establish himself in the business (Hanson et al. 2011). It has come to help the individual entrepreneurs to be in business for themselves but actually not for themselves. The ideas behind being in a franchise rather than trying other forms of entry into business such as buy out or starting an entirely new business lies on the fact that in franchise there is always already proven business formula and structure that is in place. Disadvantages In this paper, I have looked at the factors th at make franchise be considered as the major growth area in business. The above arguments have been made after a careful weighing of the shortcoming of franchising. The weighing of both the merits and the demerits of the franchise has left us with the weigh inclined to the merits. The shortcoming that could challenge this form of business could be the fact that the initial cost of purchasing franchise is high. As such, the cost may be higher than one expects. Franchising may come with detrimental strings attached. For example, the franchisee might be forced to buy products from the franchisor. This may then make the franchisee look a slave to the franchisor, as he cannot seek for other suppliers offering better deals. The above argument lies on the fact that the franchise agreement has restrictions on how the business will be operated. In such a case therefore, the franchisee is in no position of playing effectively in the dynamic local market. In case the franchisor goes out of the market, the franchisee is left like an orphan. It may take years to fully re-establish him in the business again as the franchisee fully depends on the success of the franchisor. This includes all the logistics involving the successful running of the business like advertising, legal processes, training etc (Carnal, 2007). In franchising, another important factor worth noting, which could be detrimental to the running of the franchise, is the fact that all profits, which include a certain percentage of all the sales made, are shared with the franchisor. This sometimes is done to the benefit of the franchisor leading to low profits on the part of the franchisee. On the other hand, a franchisee wishing to sell his franchise can only do so with the approval of the franchisor. This too is a demerit of franchising because, though the franchisee claims to own the business, he can do very little without the approval of the franchisor. A franchise is not flexible. Conclusion In conclusion, therefore, though demerits of franchising are there, it remains to be an effective way of getting into business. The various merits make this form of starting business be popular, unlike other forms like start up. It therefore turns out that franchising is a major growth area for business. As seen in this paper its disadvantages compared to its demerits, in comparison with other types of businesses are many. As such, we can conclusively say that franchising is a revolutionary approach to business. Effective strategies in this line of business can prove to be a benefit for new entrants in the business world and to established businesspersons wishing to venture into new areas or diversify in their current work. We can then conclusively say that ,in the corporate world today, franchising is an effective and innovative form of business yet devised to distribute products and services and as such a major growth area for business. Reference List Beer, M. (1999) Readings in Human Resource M anagement. New York: Free Press. Bowles, M. (2011)  External Environment. The Institute For Working Futures. Web. Available from:  marcbowles.com/publications.html   . Carnal, C. (2007) Managing Change in Organizations. Essex: Pearson Education. Christensen, R. (2006) Roadmap to Successful Strategic HR Management. New York: American Management Association. Hanson, D. et al. (2011) Strategic Management: Competitiveness and Globalization. Southbank, Victoria: Cengage. Michael A. Hitt, R. D. (2010) Strategic Management: Competitive and Globalization, Concepts. London: Wiley. Millmore, M. (2007) Strategic Human Resource Management: Contemporary Issues. Essex: Pearson Education. Noora, et al. (2005) The International Business Environments of Franchising in Russia. Academy of Marketing Science Review, 12.3: 2-3. Scarborough, N. M. (2010) Effective Small Business Management an Entrepreneurial Approach. London: Wiley. Zutshi, S. (2010) Property Magic 2010: How to Buy Property Using O ther Peoples Time, Money and Experience. Wiley: London.

McCarthyism and its affect on Hollywood Research Paper - 1

McCarthyism and its affect on Hollywood - Research Paper Example tical determinants of the very dark register that is affiliated with communism, and / or renunciation of aid of the government enquiry of the Communist Party and some of them were blacklisted only because their titles came to the incorrect location and time (Murray 267-79). Even throughout the firm observance of the late 1940s by the end of 1950, blacklist was seldom made explicit and verifiable, but it initiated direct impairment to the vocations of numerous American creative individuals, often as a betrayal of companionship (not to mention the principle) of cost life and assist to ideological censorship industry. The first methodical Hollywood blacklist was instituted November 25, 1947, a day after 10 writers and controllers were entitled for contempt of Congress for denying testifying before the House Committee on Un-American Activities. Group of studio bosses, portraying under the auspices of the Motion Picture Association of America, broadcast the dismissal of the artist-the so- called Hollywood Ten in what became renowned as the Waldorf Statement. June 22, 1950, booklet deserving Red Channels emerged, calling 151 amusement commerce professionals as part of the "red fascists and their supporters, shortly most of the appointees, with some other creative individuals who have been omitted from paid work in much of the amusement industry. Blacklist was competently broken in 1960 when Dalton Trumbo, a repentant constituent of the Hollywood 10, was publicly identified as a screenwriter of movies Spartacus and Exodus. Some of these very dark registers, although, is still ostracised from employed in his area for numerous years. The Committee on Un-American Activities (HUAC) was conceived in 1937 under the chairmanship of Martin dies. The major reason of HUAC was enquiring his anti-American and subversive activities. Soon after his designation, Dies obtained a telegram from the Ku Klux Klan: "Every factual American, and that encompasses all the Klansman, is behind you

Case 1; What else can go wrong Essay Example | Topics and Well Written Essays - 250 words - 1

Case 1; What else can go wrong - Essay Example If Van West could have understood Mexican culture, everything would have been easy. This is because culture dictates the way individuals treat each other, outlines that which is acceptable, the manner in which management is viewed and the way in which people approach their daily work. Since Hernandez has been helpful to Van West, he needs to inform him when it comes to business it is important to focus on your objectives. Therefore, West should transfer him to another department to avoid daily meeting while at work. In Mexican culture, a boss has the role of influencing a faction or group of people towards the attainment of a goal. Bosses are expected to lead by example, so that others are motivated to follow him and not just any individual with a position of influence. In addition, He or she is an individual who is in charge of a certain division of a company. In this case, superior people in the firm are undermining the subordinates a situation that has brewed into a cold relationship between the two groups. In order to address these issues, Van West needs to negotiate with the workers and agree on a different pay package. This will make workers change their mind about striking because they can perceive the move as inclusive and unbiased. In the end, individual relationship will improve since workers will feel safe. They will not have a negative attitude about the hierarchy since it cares about their

Corporate Governance Practices in Qatar Essay Example | Topics and Well Written Essays - 500 words - 1

Corporate Governance Practices in Qatar - Essay Example Governments are creating new regulatory frameworks to improve corporate governance of companies (Adamson, 22- 03-2011). Multinational companies are evolving and changing corporate governance to meet benchmarks and the basic requirements required by investors in making investment decisions. Companies are focusing on best practices such as risk management in order to have good corporate governance. Companies are emphasizing the management of their reputations to improve the perception of local and global community about their images. The drive to implement good corporate governance and the financial crisis in Qatar have led directors and officers of multinational companies to increase the awareness of their responsibilities. The executives are taking companies’ failure as personal liability. In Qatar, Investors are holding executives and boards responsible for unsatisfactory performance. Companies are under thorough scrutiny especially on managerial actions. Executives are aware of risks facing them. Therefore, they act to limit personal liability. The Arabic companies are embracing a more pragmatic and less litigious approach in their corporate governance to serve the international community. The Qatar government is creating new frameworks for practices and regulations that favour multinational companies. The aim of the government of Qatar to provide real business environments to attract both foreign and local investors. The greater accountability for boards and executives actions has made companies prio ritize shareholders’ interests. It is because shareholders and financial regulators put a scrutiny on issues of corporate governance. Multinational companies are now taking a proactive approach in risk management to protect executives and boards’ members. These companies are improving the standards of corporate governance to march the

Slow And Filters And Rapid Sand Environmental Sciences Essay

Slow And Filters And Rapid Sand Environmental Sciences Essay Water Purification is a process in which the unhealthy water that is contaminated, unclean, adulterated, and poisoned is converted into safe drinking water through various stage processes rendering it safe for drinking and everyday use. Water Purification is done almost every day in every part of this world. The increasing population and industrialization is generating more and more threat to the drinking water sources as a lot of harmful chemicals are being released either intentionally or unintentionally into the sources. In most of the cases we cannot see these hazardous chemicals, but they pose a great threat to our health and lives. To treat water before being brought to use, various purification methods have been developed. They vary in their design, method of filtration, equipment used, efficiency, location and various other factors. http://www.waterpurificationmethods.com/ Natural water is available from various sources like ground water, lakes, rivers and pond. It is very hard to find a pure water source in nature. Making the need to treat water and purify it before consumptions makes important. One of the objectives of water treatment and purification is to treat water from the best possible source to improve its various physical qualities, improving its taste and odour and eliminating all of the harmful contaminants. Various impurities can be classified as suspended impurities(remain in suspension), dissolved impurities(dissolved impurities and responsible for taste and odour) and colloidal impurities( electrically charged and never settle). Table 1 shows the various constituents of the impurities present in water and there effects. Ss+Tech+guide. Water for domestic use should be : Colorless and have no suspended solids; Odour free and must taste good; Free from disease causing organisms; Free of halmful salts and objectionable minerals; Free from dissolved gases which can he harm full; Should be non-corrosive in nature; Ss+Tech+guide. Table 1: Suspended and dissolved impurities in water ss+tech+guide One of the most important parts of the treatment process is Filtration. Filtration is a process in which solids particles in suspension in liquid medium are passed through porous media through which only liquid can pass away. It is required in conjugation with some kinds of chemical treatments to disinfect water of biological disease causing pathogens. [2] Crittenden, J. C. (2005).  Water treatment: Principles and design (2nd ed., p. 868). New Jersey: John Wiley Sons, Inc. The various types of filters used are Gravity Filters Vacuum Filters Pressure Filters Centrifugals and Centrifuges PROCESS OVERVIEW Suspended matter present in water makes the appearance of water cloudy; this physical characteristic is known as turbidity. This suspended mater may consist of floc, microorganisms, algae, iron, silt and manganese precipitates and also some precipitates which remain after the various earlier stages. These suspended materials are filtered by passing water through granular beds, mostly composed of layers of sand, gravel, coal. As the process goes on and on and when the head lost is more than the permissible value the filter bed is backwashed or top soil is scrapped off and brought back into operation. But there need to be a second tank which will be operation as the first one is being backwashed or top soil is scraped off. The various other important processes in the water purification process are: Screening Aeration Coagulation Floculation Sedimentation Disinfection Stabilisation Water requirements of a city/town can be divided into five categories: domestic or residential use institutional use public or civic use industrial use water system losses DESCRIPTION A sand filter is very simple in its opertion and design. It is merely a bed of sand with support of layer of gravel, in a big box like structure. Provided with various fitting for inlet and outlet of water. A set of valves to control head during various situations. Below the gravel layer are underdrains required to remove the filtered water. Before dissipaion into the sand bed the energy of the water is to be reduced so that it doesnot erode the sand bed, also reffered to as short circuiting. There is headloss during the fileration process, it occours mainly due to accumulation of particles at top surface or due to microbial growth at he surface. The filters are backwashed when stage is reached below which any head loss cannot be tolerated. For backwash the outlet valves are closed and water is made to move in opposite direction. Manual of slow sand filters Chapter 2: COMPARISON Thogh both slows sand filters and rapid sand filters function under the action of gravity and mostlly have same constituent parts yet they differ in various factors which are explaind in Table 2 below. Slow Sand Filters Rapid Sand Filters 1. Rate of Filtration 1-3-10 m/day 100-125-300 m/day 2. Depth of Bed 0.30m of gravel 1.0m of sand 0.45m of gravel 0.75m of sand 3. Size of Sand 0.25 to 0.35 mm Uniformity Coeff: 2 to 3 0.45mm and higher Uniformity Coeff: 1.5 and Lower 4. Length of run 20 to 30 to 60 days 12 to 24 to 48 hours 5. Penetration of Suspended Matter Superficial Deep 6. Preperatory treatment of Water Generally aeration Flocullation and Sedimentation 7. Method of Cleaning Scraping Back washing 8. Cost of Construction Operation Depreciation of plants Higher Lower Lower Lower Higher Higher 9. Amount of Wash Water 0.2 to 0.6% of water filtered 1-4-6% of water filtered Table 2: Comparison between Slow and Rapid Sand Filters. Class notes Chapter 3 : SLOW SAND FILTERS 3.1: Introduction Slow Sand Filters are the original form of Filtration. The history date backs to 1804 when John Gibb of Scotland used the technique of filtration to treat water for his bleachery. He used to sell the surplus water to the public. The first large scale use of sand filters was in London to treat water of River Thames in 1820. Slow Sand filters are a viable water treatment solution. Though there are some difficulties faced involved in implementation and working of the system. It possess high initial cost and its use has seen a declining phase due to few resasons but is again gaining importance after the outbreak of Cryptosporidium in Milwaukee(1993) as they are superior to Rapid Sand Filters in removing pathogenic microorganisms. The various advantages of slow sand filters over Rapid sand filters are that it is highly efficient in removal of bacteria and viruses responsible for transmitting water related diseases. Also there is no usage of chemicals involved neither do we need any highly skilled and continuous supervision. Undeniably slow filteration is best suited for rural areas as there are low running costs. Slow sand filters What happens in Slow Sand Filters is that influent water seeps through the sand bed under the action of gravity. The sand used is less uniform as compared to that used in the Rapid Sand Filters. The most of the filtration is performed in the top few centimetres of the sand bed. The process involves two stages, one being the filtration stage and the other being the regeneration stage. Slow sand filters are not backwashed as Rapid Sand Filters, in place the filter is drained off and the top few centimetres of sand media are scraped off and the filter is placed back to work. 4 prelimi 3.2 Advantages The various advantages which slow sand filters posses are that theyare really very simple in design and operation. They also require minimum chemical and power requirements thereby making it an appropriate technique for removal of suspended organic and inorganic matter. They are also very effective in removal of pathogenic organisms from water source. Because of this reason they are gaining back importance as compared to Rapid sand filters. It also helps in reduction of bacteria and various organic levels, thus helping to reduce the amount of disinfectans to be used and thereby reducing the disinfection byproducts in treated water. Other advantages which they posses are that ther are minimal sludge handling problems, no expert supervison is required and also local labor and materials can be brought to use. http://www.nesc.wvu.edu/pdf/dw/publications/ontap/2009_tb/slow_sand_filtration_dwfsom40.pdf 3.3 Disadvantages On the other hand it possess few limitations such as they require a large land area using large quantities of filter media. It also requires more of manual labour for cleaning. The sand filter can get easily clogged if turbudity levels are high in source water. Even if the nutrient content is low it may hinder in the turbudity removal action as some nutrient are needed for promotion of biological ecosystem growth. They do not completely remove all organic chemicals and dissolved inorganic sustances. Also very fine clay particles are not easily removed using slow sand filters. As the water temperature drops the biological activity drops and similar is the case in slow sand filters that if the influent water temperature is low it will decrease the biological activity within the filter making it less effective. http://www.nesc.wvu.edu/pdf/dw/publications/ontap/2009_tb/slow_sand_filtration_dwfsom40.pdf 3.4 Factors influencing Efficiency: The removal of microbes and organism is slow sand filters are performed by biological processes. And the various factors affecting the growth and functionality of bacterial growth also affect eh efficiency of slow sand filters. The various factors can as stated as below Time: the minimum and bed depth should not be less than 0.7m and flow rate around 0.1 and 0.3 m per hour, as higher the time for reaction on the filter bed higher would be the efficiency attained. Oxygen: Oxygen is important for bacteria as it uses it for its activity. If the amount of oxygen in incoming water is low or there is high organic content it would cause the filter to be less effective. Temperature: temperature is not an issue in hot countries but in countries with cold conditions they affect the efficiency as lower the temperature lower will be the biological activity in the filter bed. Maturation: Sufficient time should be provided for the biological activities to take place. Also the filter should not be cleaned too frequently. Ss tech guide for slow sand filters http://ebookbrowse.com/ss-tech-guide-slow-sand-filters-pdf-d108621291 CHAPTER 4- DESIGN CONSIDERATIONS 4.1 Design Principles 4.1.1Sizing the Filter Bed The very first step in the design is to size the bed. The depth and base area are two parameters which help to drive the rest of the design. Bed area is determined by the Hydraulic Loading Rate (HLR) selected. Hlr should be so selected such that it considers both the cariation over daily cycle and the increase each year. Pilot plant studies performed can help in determining performance characteristics. 4.1.1.1 Area The bed area is calculated using the following equation. In which HLR= hydraulic loading rate (m3/m2/hr or mgad) Q = flow (mil L/d or mgd) A = bed area (m2 or acres) 4.1.1.2 Depth of Sand The depth of sand bed is determined using the number of years the filter is to be designed before there is any need for resanding. Year of operation is determined as follows Where Y = years of operation Di = depth of initial sand bed Df = Depth of final sand bed before rebuilding is required R = depth of removal F = frequency 4.1.2 HYDRAULICS The various functions for which hydraulic analysis are required are to distribute raw water on the sand bed, collection of water, drainage of headwater, control of flow through the filter, and measurement of the headloss. 4.1.2.1 DISTRIBUTION The influent water needs to be distributed throughout the surfaceare uniformly as if entire influent water is delivered at same point, short circuiting of flow would occour. To control this kinetic energy of flow must be either distributed or dissipated. It is a matter of judgment to choose exit velocity and pipe size as there is not much of flow criteria in existence. Figure below shows a system of pipes for how distribution of water may be done. Fig : showing an approach for distributin of water over sand bed. 4.1.2.2 Collection A system of underdrains need to designed for the collection of filtered water. 4.1.2.3 Drainage For the need to scrap the sand bed, the headwater must be drained off to a level below the the sand bed surface. The figure below explains how the drainage occours in two stages. One being done at the top surface removing the top portion of headwater and the second being at the bottom removing the rest of remaining water. Fig: Shows drainage points 4.1.2.4 BACKFILLING After the drainage has been done and the scrapinf of the sand bed has been done there is need to backfill. Fot this we may use the filtered water from other sand filters operating in parallel. The filtered water is fed back to the recenlty scraped filter system using a system of valves as shown in the following figure. The Part a shows the filters working in normal condition with all valves closed. Part b shows the backfilling of filter 1 from filter 2 nad the filter 3 continues with its operations. The backfilling is done till the depth of water reaches around 1 ft above the sand saurface. It should be boted that amount of water in storage tanks should be sufficient to satisfy the demand as filter 1 and 2 are not in operation. fig. showing the various stages of backfilling. 4.1.2.4 FLOW MEASUREMENT There is a need to monitor the influent and effluent flow throughout the operation so as to maintain a constant supply and hydraulic head to satisfy the demand. For this various flow measuring devices are installed at various points like at inlet to the pland and at oultel. Also they are applied at the various inlets and outlets to individual filters. Also these meters help in keeping a record for the water demands of the community. Fot it various euipments are used such as à ¢Ã¢â€š ¬Ã‚ ¦. 4.1.2.5 Flow Control There is a 24 need to control the flow of water. There is a need to keep a check on the influent amount of water so that a constant supply is maintained. Also there is need to control flow at the effluent end of the plant to adjust according to the daily nad hourly variations in water demand. 4.1.2.6 Headloss Measurement Headloss measurement is important for the continous operation of the filter and to maintain a constant head throughout the supply. When the loss of head if below the required value is reached the scraping of filter is done followed by backfilling. To measure the headloss Piezometers need to be installed. One of it needs to be connected above the sand bed and the other to the tailwater basin. 4.1.2.7 3.5.1 Design Capacity Slow sand filtration is best suited and cost effective for population range between 30,000 to 40,000 as compared to rapid sand filtration. It shoul not be used for population higher this range because for it we need to build more number of filteraton units, and for that larger area would be required. Also if there is need for additional pre-treatment facilities like sedimentation, as always is the case, more area would be required. 3.5.2 Quality considerations of influent water The limit for turbudity of influent water should not be higher than 20 Nephelometric Turbidity Units  (NTU). But for ideal conditions it should be less than 10 NTU. If the turbudity for influent water is higher than 20 NTU, the water need to be pretreated with facilities such as grit chamber, settlink tank or a combination of various other pre-filtration systems as shown in figure below. Ss tech guide Figure 2: Schematic sequence of water treatment facilities when using slow sand filter ss tech guide 3.5.2.1 Pretreatment Facilities Fot the pretreatment of the water we may make use of Grit chambers, sedimentation tanks or roughing filters. Each of these is explained as follows. 3.5.2.1.1 Grit Chambers: These are also called as coarse sedimentation tanks. The maximum speed of water flow is around 0.75m/s. In case of the retention time it need not be very long, just a few minutes would be sufficient. In this coarse particles are removed before water goes to the settling tanks. 3.5.2.1.2 Sedimentation tank: Settling of fine suspended particles is done in the sedimentation tanks. The detention time is around 2 hours. These are further of various types like type I, II, III and IV. 3.5.6 Design criteria For the design of slow sand filters various design criteria shown in Table 3 can be used. Also to make sure there is adequate water supply and slow sand filter function properly, the flow rate should be maintained between 0.1 to 0.3 cubic meter of water per hour per square metre area of filter media. Table 3: General design criteria ss tech guide 3.5.6 Determination of size and number of slow sand filters: From the point of effluent quality, the weakest part is the edge of the filter bed. As the raw water may leak and pass the sand filter if attention is not taken while the design and operation of the filter. The way to minimise this is that the filters should not be made too small. The recommended size is around 5 m2, a workable size is around 100 m 2 , with a maximum of 200 m2. The system needs to have a minimum of 2 filters, to make sure one is in operation while the other is being cleaned. But a recommended value of 4 is good to ensure an increased and sufficient amount of treated water supply. The following empirical formula can be used to calculate an approximate number of filters required. n =  ½(A) (1/3), or n =  ¼ (Q) (1/2) Where, n Number of filter units A Total required area in m2 Q Average daily water demand expressed in m3/hr 3.5.7 Filter bed and filtration sand size of slow sand filter: There are various alteranatives to sand in sand filter bed like crushed coral or burnt rice husk. But the use of sand remains the most efficient and effective. The sand to be used is expressed in its effective size (D10) and its uniformity Coefficient. Where D10 is defined as the sieve opening that permits passage of 10% of sand by weight. And Uniformity coefficient is defined as the ratio between D60 and D10. UC = D60 / D10. The values of effective size and uniformity coefficient can be determined by performing sieve analysis as follows. Also the value of D10 for a continually operated filter is around 0.15 to 0.30mm. A mixture of 4 or 5 smaples is taken randomly to form a representative sample for the sieve analysis. It is washed to remove any impurities. Take 500 gm of the sample and using a mechanical sieving shaker, sieve it for 15 minutes. Sand retained on each sieve is weighed and added to the previous one. The grain shape for the sand filter should be perfectly round. It should be free from any clay, soil or organic matter. If the influent water is expected to be high in carbon dioxide, then there should be less than 2% of calcium and magnesium carbonates. Three important considerations should be kept in mind before deciding on the thickness of the filter bed: Immidetialtely below the top surface lies a zone in which purifying bacteria thrive. The thickness of this zone is around 0.3 and 0.4 m(in case of high filtration rate) Under this zone chemical reactions take place. It may be described as mineral oxidation zone, in which organic materials released in zone 1 are chemically degrade. Thickness of this zone is around 0.4 and 0.5 m(when water has high organic content). In total the thickness of zone 1 and 2 should not be less than 0.7m in any case. With Continuous operation for one to three months the filter starts to get clogged and the top 1-2 cm of sand bed is scrapped off including the filter skin. This layer is not replaced immediately, but done after some time. So provisions should be made for successive cleaning throughout the period. 3.5.8 Under-drains Under drains helps in efficient operation of filter. It assists in both providing support to the filter medium and to drain of the treated water to escape from the underside of the filter. Since it is laid below the sand bed, the under drainage system cannot be cleaned or repaired without any major disturbance to the sand bed. So care should be taken while designing that it doesnt get choked by granular material. One of the simplest designs consists of the main and lateral drains. Lateral drains consists of perforated PVC pipes or glazed pipes laid with open joints covered with gravel with successively increasing grain size to prevent intrusion to filter medium. In large filters it is mostly constructed of concrete as compared to PVC pipes in small filters. Figure à ¢Ã¢â€š ¬Ã‚ ¦ shows various arrangements for construction of under drain. Special considerations need to be taken care of while designing under drain system for perforated pipes as explained in tableà ¢Ã¢â€š ¬Ã‚ ¦ Figure: Arrangements for main drain Figure: various types of filter bottoms Table: Criteria for dimensioning under drain using perforated pipes Factors to be considered for the gravel layer supported by the under drains. The gravel layer is built of number of layers, with fine at top to coarse at the bottom with gradually graded grains not differing by a factor of not more than 1.41. The bottom layer of gravel should have a grain diameter of at least double the size of the openings into the drainage system. Each successive layer should be graded such that the its smaller dia (D10) particle diameter are not less than four times than those of layer immediately below. If the joints are 8mm or less wide, the following values for D10 and D90 would be sufficient with three layers. D10(mm) D90(mm) Top Layer 1 1.4 Second Layer 4 5.6 Third Layer 16 23 In slow sand filters the gravel should conform to specifications similar to filtering medium, like it also should be hard, rounded, free from sand, clay, dirt and with specific gravity of at least 2.5. Also after immersion in concentrated hydrochloric acid for 24 hrs. The weight lost should not be more than 5% by weight. For the thickness of the layer, it should be at least 3 times the diameter of the largest stone. The gravel layer should be placed with care as any movement may disturb the filter sand above or may choke the under drain. 3.5.6 Factors influencing slow sand filtration efficiency Since the process of removal of microbes and organisms in filter is completely biological, the efficiency depends on various factors such as time, temperature, oxygen and the beneficial microbes. They are explained as follows Time: For biological processes to take place time plays a critical role. So sufficient amount of time should be provided for the reactions to take place. Time is determined by the depth of sand bed provided and the flow rate. The sand depth should not be less than 0.7m and flow in between 0.1 and 0.3 m per hour. Oxygen: Oxygen I required for the activity of bacteria in the filter bed. So sufficient amount of oxygen level should be maintained in incoming water as low amount would affect the efficiency of the slow sand filter. Temperature: Hot temperature is best for the bacterial activity. Its not a problem in hot countries, but in cold countries attention need to be given to the temperature conditions. Maturation: Bacterial growth is not that fast during the initial stages of the filter and also after every time it is cleaned. So it is suggested not to clean the filter bed too often. 3.5.7 Effluent Quality The performance of slow sand filter in terms of various factors like colour, turbudity, organic matter, etc. are given in tableà ¢Ã¢â€š ¬Ã‚ ¦. Table.. Performance of slow sand filter

The Slave Trade :: essays research papers fc

Intro: Slavery, the owning of slaves as a practice or institution. The condition of being a slave, bondage, servitude. Slave, a human who is owned as property by, and is absolutely subject to the will of another: bondservant divested of all freedom and personal rights. Hard to believe but on of the most horrifying occurances in World History, is the Slave Trade. It was a time in which people were sold as merchandise, where human beings were being treated as if they were not human. Beaten, being taken on a ship to an unknown land, drowned because of rations, and space, inhumane........ yes, unrealistic........ no. What was it? The capture and forced labor of Africans by Europeans began in the early 16th century. Africans were rounded up by other Africans as objects of trade with the Europeans. Eventually, slave ships became a regular sight in what came to be known as "the Middle Passage." These ships provided a constant flow of African slaves to Brazil and the Caribbean Isla nds, where the human cargo was auctioned off and brought to Europe or the New World.. Many of the ships wee not cleaned. The "cargo" was not feed or cleansed properly. Many captives died from the inhuman conditions on these voyages. Who had control? England gained control of the slave trade under the Treaty of Utrecht in 1713, and managed the shipment of slaves to Spanish colonies. As the colonies gained independence from Spain, they outlawed slavery, and soon slaves were most in demand in North America, particularly on plantations. Few were fortunate enough to be house servants; most performed menial labor in the fields. How did it end? As far back as the mid-1500s, Jean Bodin, a French political philosopher, condemned the institution of slavery as immoral and unnatural.