Tuesday, December 31, 2019

Description And Description Of A Computer - 2309 Words

Name Picture Use Communicating Motherboard All of the main components in a computer connect to the motherboard the board allows all the things on it to computer to communicate. This board contains the Northbridge and the Southbridge. The Northbridge controls the main communications on the board between the ram, CPU and PCI-e. The Southbridge communicates with PCI, SATA and things like USB and audio. CPU The central processing unit does all the calculations to process the data that is requested by the operating system. The CPU connects through a socket in the motherboard and communicates with the Northbridge which communicates with the ram and the rest of the computer to produce the data for the CPU. Cache The cache is inside the CPU. Where the CPU uses it as very high speed storage where data is stored as it is processed this data is then offloaded into the ram. The cache only communicates with the CPU as this is what gives it all its data and tells it what to store. Ram Ram temporarily stores the data that is being processed by the CPU. This type of storage is very fast so the computer can work faster than using the data directly from the HDD. However this is volatile memory so when power is lost everything in the ram is lost. The ram communicates with The CPU and the rest of the motherboard via the Northbridge. It receives and stores data then sends the data when it is give a command to do so. Heat sink The heat sink sits on top of the processor and drawsShow MoreRelatedHardware And Software For Graphics Studio1499 Words   |  6 PagesHardware and software for graphics studio CPU/Processor AMD Black Edition – FX 4 GHz Processor Description The CPU or central processing unit is responsible for reading and completing or delivering commands from the hardware and the software. It is said by many people to be the brain of the computer. Integrated CPUs can have multiple cores or multiple processors on a single chip, these are multi-core processors and have more power than a normal processor as it is able to do multiple tasks at theRead MoreSelf Introduction975 Words   |  4 Pagesif the candidate would be a good fit for the job description. Once students have created their self-introduction essay, they can adapt it into a 1 minute speech that can be used during their job interview. 1 Intensive Business English Leadership Self-Introduction Specifications and Suggestions ï‚ · ï‚ · ï‚ · ï‚ · ï‚ · ï‚ · ï‚ · Your essay should be short and concise. Be sure to review the job description and tailor your essay to fit the job description and the organization. Be sure to identify all ofRead MoreNurse Informatics Position Description For An Informatics Nurse Specialist1217 Words   |  5 PagesNurse Informatics Position Description Many job titles or description can be associated with the position of an informatics nurse specialist (INS). According to Sweeney (2010), there is no single job description for an individual with a graduate level of education in the informatics field. Furthermore, the author stated that job titles and/or description of an INS varies with each employing organization. However, expected activities should include responsibilities such as administration, projectRead MoreEnterprise Architecture : Architecture Vision772 Words   |  4 PagesEKANKI GOVEKAR ENTERPRISE ARCHITECTURE PROJECT – ARCHITECTURE VISION CLINET – XYX CORP. PREPARED BY –EKANKI GOVEKAR Table of Contents 1. Purpose and Project Establishment. 2. Problem Description (Business Principles ,Summary of Principles) 3. Objective 4. Scope 5. Constraints 6. Architecture Vision 7. Architecture Work and Approval 1. Purpose and Project Establishment. The Architecture Vision is the early phase of Enterprise Architecture and provides high leverRead MoreJob Descriptions772 Words   |  3 Pagespaper locates several job descriptions that apply to the position provided. It compare the common tasks and behavioral objectives contained within the job descriptions or lists of duties. The paper also includes customized job / task analysis and describes the organizational situation that will benefit from the type of job / task analysis, identifing opportunities for appropriate training that support this job and its corresponding tasks. 1. Locate several job descriptions that apply to the  position  youRead MoreBusiness Information System Essay709 Words   |  3 PagesTable of Contents 1. General Description 2. External Description 3. External View 4. Internal Description 5. Internal View 6. Further Notes 7. References 1. General Description of the Information System Title Online Airplane Ticket Reservation Information System (OATRIS) General Description OATRIS is the system that help user to buy airplane ticket through Internet. It processes user’s preferred flight timeline and the payment. Then, transform it into e-ticketRead MoreVHDL Research Paper995 Words   |  4 PagesCircuit. The HDL stands for Hardware Description Language. Clearly, the state of technical a airs these days has done away with the need for nested acronyms. VHDL is a true computer language with the accompanying set of syntax and usage rules. But, as opposed to higher-level computer languages, VHDL is primarily used to describe hardware. The tendency for most people familiar with a higher-level computer language such as C or Java is to view VHDL as just another computer language. This is not altogetherRead MoreComputer Information And The Byu Idaho Catalog1343 Words   |  6 PagesComputer Information and Networking is a large and growing field that provides those with the appropriate skills and education a wide range of possible job opportunities. The BYU Idaho catalog has the following to say about careers in Computer Information Technologies: Careers in CIT are dynamic. New challenges and opportunities await you every day. Working in a team, you will interact cooperatively with the management, customers, clients, and other information technology professionals to determineRead MoreReview Of Dennett And Picard 1006 Words   |  5 Pagesdesigning a robot that feels pain to initiate a more detailed pain experiment. The example of computer simulation of hurricane shows that to conduct a qualified simulation program requires a definite theory of the conditions and behaviors of the object to be simulated. First, we write a program according to the theory of pain, input the descriptions of conditions in text, then the computer types the descriptions of results in text. But this time it only gives an exterior behavior, so the program is modifiedRead MoreUnit 2 Business Resources1106 Words   |  5 Pagessuch as application forms, CVs (curriculums vitae) personal statements and job descriptions. An application form is very impor tant as it provides vital information from the applicants to the business. An application form includes the personal details of the applicants such as name, age, address etc. It also includes other type of information such as right to work in the UK, criminal history etc. CVs are written description of a person’s work experience, educational background and skills (This includes

Monday, December 23, 2019

Why Cheating Is Becoming More Prevalent Of Today s...

Sitting in class as a freshman in high school, Jonny looks around during his test as the teacher stepped out of the room. He hears the loud whispering voices of his peers discussing the unknown answers. Thinking to himself he contemplates asking his friends for answers. He assumes it is acceptable because everyone around him is doing it, so he decided to take part in the discussion. When the teacher returns everyone is silent. No one was caught and no one is going to get into trouble. The scheme was successful. Students are now finding ways to make cheating acceptable. Generally students only want to get their work done rather than truly learn the material. Causes of cheating is becoming more prevalent in today’s education system because it is becoming easier to get around the rules, there are many pressures, and students do not always get punished as they should. To excel in a subject, students will do whatever it takes. A class that a student may succeed in without cheating, they are now beginning to cheat because they want to spend less time and continue to obtain good grades. All students spend an excessive amount of time in school doing work, and they do not want to go home and continue their schoolwork. They feel like they will be at a set back if every student is cheating, then they believe they have to cheat in order to keep up with the others. Many times peer pressure is a huge factor for why cheating begins. Students are smart enough to achieve their goals it isShow MoreRelatedPlagiarism: a Social Problem1696 Words   |  7 Pagesnine (Lathrop). Plagiarism is the unauthorized use or close imitation of the language and thoughts of another author and the representation of them as ones own original work (Plagiarism). Many are noticing how plagiarism is becoming a more prevalent problem in schools today and the thought of plagiarism is on many intellectual minds. Warnings about plagarism are included on every syllabus distributed on the first day of class, accompanied by a lengthy discussion of the same topic delivered fromRead MorePlagiarism in an Academic Environment2501 Words   |  11 PagesIn the Academic world today, the rising incidences of plagiarism are putting more schools and universities on high alert, and zeroing in on how to detect and prevent it. Academic institution’s often have a Student Code of Academic Integrity. Students, whom are caught cheating, can be given warnings, bad grades or even expelled out of school. Today, information is flowing freely and with ease through the Internet. Having this opt ion would make students think more about cheating. According to a surveyRead MoreCellular Devices During Instructional Periods1939 Words   |  8 Pagesover time causing it to be brought into education within school systems. The use of cellphones in school is a topic that many educators argue about. The main issue regarding the use of cellular devices during instructional periods is whether or not it affects the student’s overall ability to succeed in school. It is important to talk about whether or not students benefit from using cellphones because the use of cell phones affect future generations and education. For instance, if a school’s overallRead MoreCorruption Is Barrier to Development in Pakistan9592 Words   |  39 Pagespolicies B. Arrival of foreign remittance C. Afghan War 2. A barrier to development in Pakistan A. A crime against prosperity B. A barrier to justice C. A barrier to democracy D. A crime against the environment E. A barrier to health F. A ba rrier to education 3. Anti-corruption agencies 4. Transparency International report about Pakistan 5. Corruption Perception Index 6. National Corruption Perception Survey III. IV. V. Suggestions for eradication Conclusion References TI Pakistan’s Time to WakeRead MoreProblems of E-Commerce6457 Words   |  26 PagesProspects and Problems Of E-commerce Prospects and Problems of E-Commerce Prepared for S I Nusrat A Chaudhury Associate professor Department of Business Administration Head of Career Counseling Center East West University Prepared by Razoanul Amin Talukder 2005-2-10-207 Sazzad Hossain 2005-3-10-091 Tanzia Afrin 2005-2-10-271 Sk. Abdul Mukit 2005-2-10-135 Golam Kibria 2005-3-10-136 Date of Submission: April 13, 2008 [pic] 10 April 2008 Read MoreAnnotated Bibliography: Plagiarism39529 Words   |  158 Pages45-50. Deguen, S., Sà ©gala, C., Pà ©drono, G. and Mesbah, M. (2012), A New Air Quality Perception Scale for Global Assessment of Air Pollution Health Effects. Risk Analysis, 32(12): 2043-2054. Hassoun, N. (2012), Global Health Impact: A Basis For Labeling And Licensing Campaigns?. Developing World Bioethics, 12:  121 134. Mackey, T. M. and Liang, B. A. (2012), Promoting global health: utilizing WHO to integrate public health, innovation and intellectual property. Drug Discovery Today, 17(23-24): 1254Read MoreIncreasing Crimes7023 Words   |  29 PagesNational Crime Records Bureau, incidences of crime since the early days of independence has gone up by more than 5 times, and this ofcourse excludes the large number of unreported crimes, especially related to smaller thefts, crime against women and the many cases where the police just refuse to file an FIR. The western countries aren’t any better off either, with the UK recording an average of more than 2 violent attacks everyminute ( a very high figure for such a small country) and the US, whichRead MoreAn Exploratory Study of Internal Control and Fraud Prevention Measures in Smes5855 Words   |  24 Pagesand the presence of appropriate fraud preventive measures will help to improve SMEs performance. Keywords: Internal Control, Fraud and Pre vention Measures, Small and Medium Enterprises 1. INTRODUCTION Small and medium enterprises (SMEs) are much more vulnerable proportionally to fraud by employees, and much less able to absorb these losses than large corporation. The entrepreneur’s principal objectives are profitability and growth, the business is characterized by innovative strategic practicesRead MoreIntercultural Communication of American Tv Series in China6643 Words   |  27 PagesAbstract†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦..â… ± â…  . Introduction†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. â… ¡. The intercultural communication theory 2.1 The definition of the intercultural communication 2.2 The way of intercultural communication â… ¢. The reasons why American TV series are popular in China†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 3.1 The communication of American TV series in China 3.1.1 The background information of TV series †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 3.1.2 The history of American TV series spread 3.2 The reasons that The Big Bang Theory is popular inRead MoreThe Growing Problem of White Collar Crimes in India19963 Words   |  80 Pageswhether improved standards of corporate governance could be achieved through adoption of principle based standards of conduct. Perhaps the most vital corporate governance legislation in recent years is the Sarbanes-Oxley Act, 2002 of US which is becoming a global benchmark for internal best practices in corporate governance. The inclusion of White Collar Crime Penalty Enhancement Act, 2002 in the corporate reform package creates new substantive offenses, significantly enhances financial and incarceration

Sunday, December 15, 2019

Material Balances for Carbon Free Essays

Many of the earth’s natural processes are cyclic. The circulation of water between oceans, atmosphere and continents is a familiar example. Another is the transformation and movement of carbon-containing compounds for which the immediately obvious elements are the photosynthetic generation by plants of carbohydrates from carbon dioxide and the consumption of carbohydrates by herbivores who regenerate carbon dioxide through respiration. We will write a custom essay sample on Material Balances for Carbon or any similar topic only for you Order Now (As we shall see shortly, the complete carbon cycle involves a number of additional processes.) Such cycles are termed â€Å"biogeochemical cycles. † The term is most commonly used to refer to global cycles of the â€Å"life elements† C, O, N, S, and P, but its use is extended as well to regional cycles and to other elements or components. The study of biogeochemical cycles then is the study of the transformation and transport of substances in the Earth’s systems. In most cases the cycles link biotic (living) subsystems to abiotic (non-living) ones. Of particular current interest is the effect of human-caused disturbances on the natural cycles. A major disturbance in the carbon cycle, for example, is the continuous injection of carbon (mainly as carbon dioxide) into the atmosphere by the burning of fossil fuels. How much of this injected carbon ends up in the atmosphere? How much in the oceans? . . . in the land vegetation? What effect does the increase in carbon dioxide in the atmosphere have on the global climate? Insights to the answers to these and related questions can be gained through the use of mathematical models constructed by applying material and energy balance principles. Here the carbon cycle serves as an illustrative example, though much of the discussion is couched in terms that apply generally. The objective is to develop a simple mathematical model that will demonstrate the use of material and energy balances for studying the Earth’s natural processes. A schematic representation The transport of substances in biogeochemical systems is commonly depicted graphically by means of flowsheets or flowcharts, which are composed of boxes (or compartments, or reservoirs) connected by arrow-directed lines. As such, the depiction resembles the flowsheet for a chemical plant or process where boxes represent various 1  units (reactors, heat exchangers, etc. ) and the lines represent material flows. Indeed the analogy extends to methods of analysis, as we shall see in later sections, based on material and/or energy balances. Flowcharts for biogeochemical systems differ from those generally used for chemical processes in that a single chart for the former usually is used to track the flow of just one substance (ordinarily an element such as carbon) — but it need not be so. The number of boxes in a schematic representation is indicative of the level of detail to which an analysis will be subjected or for which information (data) is available. The least detailed for global carbon, for example, consists of only three compartments — for land, oceans and atmosphere — of the type shown in Figure 1. Commonly in such representations, the amounts, or inventory, of the substance of interest (represented by M’s in Figure 1) in each compartment have units of mass or moles. The exchange rates or flows (usually termed â€Å"fluxes† in the ecosystem literature, represented by F’s in Figure 1) have units of mass or moles per unit of time. Figure 1. Three-compartment representation of a biogeochemical cycle. M’s  represent the inventory (mass or moles), and F’s are flows or fluxes (mass or moles per unit time). atmosphere, Ma Foa Fao oceans, Mo Fta Fat land, Mt (terrestrial system) A quantitative description would give numerical values of the inventories and fluxes — or better yet, would give expressions for the F’s in terms of the M’s. Figure 2 presents a similar flowchart with a slightly higher level of detail. This representation recognizes that there may be a significant difference between concentrations near the ocean surface and those in the deeper ocean layers. We will use this representation later for studying a model of the carbon cycle. 2 atmosphere, Ma Fsa Figure 2. Four-compartment representation of a biogeochemical cycle. Fas surface ocean layer, Ms Fds Fta Fat land, Mt (terrestrial system) Fsd deep ocean layers, Md A further level of detail might add boxes to represent land and ocean biota, but we will not add that complexity for our purposes here. Mathematical models Mathematical models of biogeochemical cycles can take on various forms depending on the level of detail sought or necessary and/or on the type of supporting or verifying information or data available. In general, models attempt to relate the rates of transport, transformation and input of substances to their masses and changes by way of equations based on material and/or energy conservation principles. The description in the preceding section suggests so-called â€Å"lumped† models; that is, models in which the spatial position is not a continuous variable. Indeed it may not even appear in the model equations. It is, in fact, considered to be piecewise constant. Thus the vertical position in the ocean was separated into two parts, surface layer and deep layers. For such lumped models, the mathematical description is in the form of ordinary differential equations for the unsteady states and of algebraic or transcendental equations for the steady state. So-called â€Å"distributed† models, which consider the spatial position to be a continuous variable, lead to partial differential equations for the unsteady and ordinary differential equations for the steady state. By far the most common models employed for biogeochemical cycles are of the lumped variety, and the remainder of this module will be devoted to them. One should think of lumped models as representing overall (perhaps 3 global) averages. With sufficient detail (large number of boxes) they may be useful for accurate quantitative purposes; with little detail, they may be used to obtain rough estimates, to study qualitative trends, and to gain insights into the effects of changes. Lumped models are sometimes referred to as â€Å"black box† models — so called because they consider only the inputs and outputs of the boxes and their interior masses. They do not explore the interior details of the boxes — such as the predator-prey interactions that influence the population dynamics within the biota, or the complex ocean chemistry that affects the air-ocean exchange of material. In the same way, most flowsheet representations and calculations for chemical plants treat process units as black boxes. Material and energy balances relate known and unknown stream quantities. The detail within a box, such as the tray-to-tray compositions and temperatures of a distillation column are not directly involved in the usual flowsheet calculation, but obviously are involved in determining the output streams, or in relating them to other streams, at a finer level of detail Calculations for a model of the carbon cycle Here we will use a schematic diagram similar to that in Figure 2 to construct a mathematical model for the carbon cycle. Our purpose is to estimate the effect of fossil fuel burning on the level of carbon in the atmosphere — important information for the assessment of the greenhouse effect. Figure 2 is reconstructed below to include the input of carbon from fossil fuels. atmosphere, Ma Fsa Figure 3. A simplified representation of the carbon cycle, including an input from fossil fuel burning. Fas surface ocean layer, Ms Fds Fat land, Mt (terrestrial system) Fsd deep ocean layers, Md  4 Fta Ff fossil fuels The following equations relate the flow rates (fluxes) in the diagram to the masses of carbon in the boxes in the form employed in references [1] and [2]. The numerical values of the coefficients were derived from data presented in those references. Ffa is an input disturbance, yet to be specified. In these equations, the masses (the M’s) are in units of petagrams, and the fluxes (the F’s) are in units of petagrams per year. (One petagram is 15 10 grams. ) Fas = (0. 143) Ma (1) Fsa = (10 ( 2) ?25 )M 9. 0 s Fat = (16. 2) Ma0. 2 (3) Fta = (0. 0200 ) Mt ( 4)  Fds = (0. 00129) Md (5) Fsd = ( 0. 450) Ms ( 6) Notice that Equations 2 and 3 are nonlinear relationships between fluxes and masses. To appreciate the reason for this, say in Equation 2, bear in mind that the fluxes and masses are measures of the element C, which actually exists in various compound forms, with equilibrium likely established among them, in the ocean waters. Yet it is only carbon dioxide that enters the atmosphere from the ocean layers in any appreciable quantity. Therefore, the relationship between carbon dioxide and the total carbon in the ocean layers is complicated. The nonlinear relationship in Equation 3 is explained by the fact that this rate of transfer, nearly all in the form of carbon dioxide, is governed mainly by the rate of photosynthesis by plants — a rate usually not limited by carbon dioxide supply from the air but rather by the photochemical and biochemical reactions at play. Material balances Material balances on carbon (i. e. , atomic balances) may be written for each of the boxes in Figure 3. As an example, with the information in Equations 1-6 incorporated, the unsteady balance on the â€Å"atmosphere† box is given by 5 dMa 0. 2  = (10 ?25 ) Ms9. 0 + (0. 0200) Mt ? (0. 143) Ma ? (16. 2 ) Ma + Ff dt ( 7) Similar balances must be added for the other three compartments, and initial values for the four M’s must be given to complete the mathematical model. The input from fossil fuel consumption, the disturbance function Ff, may be a constant or a function of time. Its current value is about 5 petagrams of carbon per year. Over some periods of time its value increased at the rate of about 4% per year. Inasmuch as the Earth’s total reservoir of fossil fuels is estimated to be 10,000 petagrams, of which only half may be  recoverable for use, the current use rate, much less any significant increase, is not sustainable indefinitely. However, in the much shorter run, the concern is not about the availability of fossil fuels, but about how their use may be affecting the global climate. Steady states . The steady-state model is derived simply by setting the time derivatives in the transient equations to zero. Further, we can deduce from physical considerations that no steady state is possible unless Ff is zero. (Notice that the steadystate equations are nonlinear in the M’s owing to the exponents on Ms and Ma. Consequently, a numerical search procedure must be used to obtain solutions to Problem 1 below. ) Problem 1 Incorporating the information in Equations 1-6, write the steady-state carbon balance for each of the four â€Å"boxes† in Figure 3, taking Ff to be zero. Can you solve these equations for the numerical values of the four M’s? (Note that the equations are not linearly independent; one is redundant. ) (a) Take the total M (i. e. , the sum of the four M’s) to be 39,700 petagrams (the actual current estimate of the total carbon in the four compartments) and solve for the M’s. Note that your solution would be the ultimate steady-state distribution of carbon if the usage of fossil fuels were discontinued now — that is if Ff were immediately decreased from 5 petagrams per year to zero. (b) Instead of assuming an immediate reduction in Ff to zero, suppose that the usage of fossil fuels is reduced gradually in such manner that the carbon entering the atmosphere from this source decreases linearly with 6 time from 5 petagrams per year to zero over the next 100 years. Calculate the total amount (in petagrams) of carbon released by fossil fuel use over that 100-year period, and determine the new set of M’s at steady state. What fraction of the added carbon will ultimately (steadily) reside in the atmosphere? Unsteady (Transient) States. While information about steady states is of interest and importance, the more relevant questions can only be answered by examining the transient or unsteady state. How long does it take to approach a steady state? What levels of carbon are reached in the atmosphere along the way to an eventual steady state? What is the effect of increasing or decreasing the rate of consumption of fossil fuels? Consider the first question. According to the numerical values given above for fluxes and reservoir levels of carbon, the effective time constants for the reservoirs vary from a few years for the atmosphere to hundreds or thousands of years for the deep ocean layers. Therefore, a large input into the atmosphere may eventually decay to only a modest permanent (steady-state) increase owing to the fact that the large capacity of the oceans will eventually absorb most of it — but the effects on the atmosphere may be felt for a century or more. The point was made above that the steady-state equations, being nonlinear, cannot be solved analytically. The same is true for the unsteady state. Therefore, the following problem requires a numerical procedure for solving the system of nonlinear ordinary differential equations. Problem 2 . Equation 7 gives the material balance for carbon in the atmosphere. Complete the mathematical description of the unsteady state by writing similar balances on the remaining three compartments shown in Figure 3. Take the initial (current) levels of carbon in the four reservoirs to be 700, 3000, 1000, 35000 for the atmosphere, terrestrial, surface ocean, and deep ocean reservoirs, respectively — all in petagrams. (a) Assuming that the carbon input from fossil fuel use remains constant at its present level of 5 petagrams per year, generate a numerical solution giving the amount of carbon in each reservoir versus time over a 100-year period. (Show your results in graphical form. ) (b) As in part (b) of Problem 1, let Ff decrease linearly with time from 5 petagrams per year to zero over 100 years. Again generate solutions and present curves showing the 7 reservoir levels of carbon versus time up to 100 years. What fraction of the total carbon entering the atmosphere from fossil fuel use is present in the atmosphere at the end of the 100-year period? Compare that fraction to your answer for part (b) of Problem 1. Comments? A Glance at the Global Warming Problem You might ask why should we be concerned about changes in atmospheric carbon levels. After all, the levels are very low. Further, we should expect some natural level of CO2 in the atmosphere owing simply to that generated by the respiration of plants and animals. In fact, that natural level is estimated to be about 280 ppmv — a pre-industrial level that probably existed steadily for centuries before the industrial revolution. The answer to such questions is not simple, but the major concern nowadays is the possible upsetting of the Earth’s energy balance leading to an increase in the average global temperature. We will not attempt an exhaustive treatment of this subject here, but since it connects directly to the preceding discussion of the carbon cycle, it warrants a quick glance at least. The following equation gives the simplest form of the Earth’s energy balance. S(1 ? f ) r = 2 4 2 T (4 r ) (8) where S is the solar constant — i. e. , the amount of incident solar radiation per unit projected area of the Earth, f is the albedo or reflectivity of the Earth, r is the Earth’s radius ? is the effective emissivity of the Earth for infrared radiation to outer space, ? is the Stefan-Boltzmann constant T is the absolute temperature — indicative of the global average temperature. The radius, r, cancels from Equation 8. The following list gives values for the other quantities in Equation 8. 2 S = 1367 watts/m f = 0. 31 ? = 0. 615 -8 2 4 ? = 5.5597 x 10 watts/(m oK ) 8 Equation 8 is a steady-state balance equating the solar energy reaching the Earth’s surface (on the left side) to the energy lost by infrared radiation to outer space (on the right side). Atmospheric gases affect the reflectivity, f, and the effective emissivity, ?. In particular, so-called greenhouse gases decrease ? by absorbing, or â€Å"trapping†, some of the infrared radiation, thereby reducing the amount of energy that can escape from the Earth. If all other factors are constant, a lower value of ? will result in a higher value of T from Equation 8. Other factors come into the picture, however, and lead to uncertainty about the extent of global warming that may occur due to increases in CO2 and other greenhouse gases. For example, an increase in the average temperature would probably lead to an increase in aerosols and cloudiness, which will act to increase f and offset the effect of a decrease in ?. We probably error on the pessimistic side (i. e. , predicting a temperature change that is too large) if we assume, as we shall here, that an increasing CO2 level works only to decrease ?. The following equation gives a reasonable estimate for that variation. = 0. 642- (8.  45 x 10-5) pco 2 (9) where pCO2 is the concentration of carbon dioxide in the atmosphere in parts per million by volume (ppmv). Problem 3 For this problem you will need to calculate the concentration of CO2 in ppmv from the total mass of atmospheric carbon. For that calculation, take 18 the total mass of the atmosphere to be 5. 25 x 10 kg. In all cases use the initial values for the M’s given in Problem 2. (a) Using your result from Problem 1(b) along with Equations 8 and 9, calculate the predicted eventual increase in the global temperature attributable to the carbon added to the atmosphere over a 100-year period. (b) Repeat Problems 2(a) and 2(b), this time including a graph of the global temperature change versus years as predicted from Equations 8 and 9. Comment about the resulting temperature following from Problem 2(b) vis-a`-vis that following from Problem 1(b). 9 Problem solutions Solutions to the three problems presented in these notes are available to course instructors as Mathcad (Macintosh) files or as copies of those files in pdf format. Copies may be obtained by e-mail request to schmitz. 1@nd. edu. How to cite Material Balances for Carbon, Papers

Saturday, December 7, 2019

Chandas Secret Essay free essay sample

You may also bring a print dictionary. Write the rough draft of your essay in class. Double space your work so you have room for editing and revision. (Don’t waste time copying your quotations onto this draft; simply indicate where you plan to put quotation â€Å"A†, quotation â€Å"B† etc. ) Hand it in at the end of class. Day 3 – Edit and Complete the Final Draft Your draft will be returned to you for editing and revising. 1. Revise your rough draft to ensure that you have: ? a strong thesis ? a clear organizational plan (point, proof, analysis) transition words ? insightful arguments ? smoothly embedded quotations ? effective use of language ? correct spelling, grammar and punctuation. 2. Write a final copy, including accurately transcribed quotations and using proper MLA format. Double space your work. Proofread and make any final revisions. Do not rewrite. 3. Highlight your thesis statement and the topic sentences of each of your body paragraphs. We will write a custom essay sample on Chandas Secret Essay or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page 4. Prepare a Works Cited page for your essay. 5. Give your essay a creative title 6. Hand in your essay, along with your single sheet of notes, first draft, and rubric. See the back of the sheet for topics†¦ VERBAL INSTRUCTIONS ACCOMPANY THIS DOCUMENT Topics – Choose ONE 1. A hero is a person of distinguished courage or ability, admired for his/her brave deeds and noble qualities. Choose one of the main characters from the novel and show why that character might be considered a hero. Support your answer with proof, in the form of examples and quotes, from Chandas Secrets. 2. Through the novel, Chanda matures and attempts to deal with the intolerance and prejudice in Bonang, Africa. Show how she is shaped by both positive and negative influences of people in her life, particularly, her mother Lilian, Mrs. Tafa, and Esther. 3. Trace the development of one of the main characters through the course of the novel. Show what he/she is like when we first meet him/her, as well what he/she is like at later points through the story, and finally what he/she has learned by the end of the book. Look for evidence of his/her growing understanding about the world. Helpful essay hints: †¢ Write in the present tense and avoid abbreviations and contractions. †¢ Avoid â€Å"I†, â€Å"we†, â€Å"you†, and informal expressions †¢ Start with an engaging hook. †¢ Ensure that each of your body paragraphs include a topic sentence, point, proof, analysis x 2 or 3, and a concluding sentence. †¢ Use transition words to enhance coherence. †¢ Use proper MLA citation format. †¢ Provide a thoughtful conclusion that leaves the reader with something to think about.