Data Abstraction

According to the Merriam-Webster online dictionary, the word abstract is defined as â€Å"disassociated from any specific instance† or â€Å"expressing a quality apart from an object†, or â€Å"having only intrinsic form with little or no attempt at pictorial representation or narrative content†.From these definitions, it can be possible to get an idea that to abstract an object implies something ethereal and nebulous, completely disjoint from a concrete instance of that object. In an idea reminiscent of Plato, the world can be separated into two things – the abstract idea and the concrete instance.Understanding the concept of the abstract data type or ADT is easier knowing the definitions of abstraction. An ADT is a representation of a concrete instance. Computers can only process ones or zeros and can only store long ones and zeros.However, in building programs a programmer might want to develop code that interacts or models real world objects or process es. ADTs are â€Å"invented† data types – data types that are modeled after the abstract idea of the concrete instance. An example is the string data type found in some programming languages.A computer cannot store a string (only ones and zeros) yet programmers can do operations on a string like concatenation (using the + operator) effortlessly as if the computer or compiler understands that the user is working with sentences.This brings to light an important concept when dealing with ADTs – the concept of information hiding. A compiler designer might engineer a programming language to handle strings in many ways. He may choose to use ASCII or EBCDIC, use 8 bits per character or a full 32 bit word, use little endian or big endian storage.All these choices are invisible to the user. All the developer needs to understand is that to concatenate strings uses a â€Å"+† operator. Indeed, for an abstracted data type to be functional the functionality of that da ta type should reflect that what that ADT represents independent of the implementation.The nitty gritty of its workings is hidden behind a wall called the interface. The interface (associated operations, properties, etc) is all that the programmer needs and should need to   know. A good wall is a prerequisite of good ADT design.So far the paper has discussed about ADTs as data types that represent an idea (such as a string) that is not natively supported by the hardware. A developer might also make his or her own ADTs through the use of data structures.A data structure is basically just an ordered way of organizing data. An example of a data structure is the struct in C, linked lists, and trees. A developer may choose to create one of these data structures in order to represent an abstract idea. He may choose to use a tree in order to represent a family tree.In designing user created ADTs, the concept of information hiding should still be remembered. The ADT should provide a const ant standard interface for every method or subroutine that chooses to call it. Additionally, it goes without saying that the data structure of choice should efficiently model the abstract idea it represents. Using a tree to represent genealogy is easier and makes more sense compared to using linked lists.A soda vending machine, even though it is quite simple is a good illustration of the many aspects of ADT design. The developer might need to store the types of sodas the machine is selling. As there is no â€Å"soda† data type, the programmer might use strings. When the machine vends, the machine should also know that there is one less soda in its storage.A programmer might then choose to implement the sodas as a stuct composed of one string (for the soda name) and an integer representing the number of soda cans left. When the customer presses a button corresponding to a soda, the soda name is displayed on the screen and the machine checks if there are still soda cans left.If there are cans left, the vend process continues through with the customer getting his soda (after payment of course) and the integer counter for the soda is decremented by one. However if the counter is of value zero already, the machine halts the operation and tells the customer to pick another soda.BibliographyCarrano, Frank, and Janet Prichard. Data Abstraction and Problem Solving with C++ Walls and Mirrors. 3rd ed. Boston: Addison-Wesley, 2001.Sedgewick, Robert. Algorithms in C. 3rd ed. Boston: Addison-Weslet, 1998.Sun Developer Network [Website], java.sun.com

Biology Osmosis Observation

Biology laboratory work: Osmosis observation Measuring the dependence of net mass gain in potato pieces on concentration of sugar solution By Jonas Kulikauskas Siauliai Didzdvaris Gymnasium Hypothesis: The more sugar in solution, the more potato mass will decrease. Aim: To see how potato mass will change at different concentration solution. Research question: How the mass of potato will change at different concentration solutions? Variables: Dependent: solution concentration.Independent: sugar concentration in potatoes. Controlled: time, potato form. Apparatus: 1. 5 plastic cups 2. Distilated water 3. Potato 4. Knife 5. Clock 6. Electronical scales (Â ±0,05) 7. Bag of sugar 8. Measuring cylinder 9. Tap water Method: Peeling down the potato and cutting it into 1cm3 cubes (25 cubes) Weighing potatoes on the scales Putting different amount of sugar into five plastic cups (1st no sugar 2nd 6,8g 3rd 13,7g 4th 20,5 5th 27,4g) Adding 100ml of water to each of the cups Mixing the sugar with waterPutting in 5 potatoes into each cup Waiting 20 minutes Pulling out the potatoes, drying them up and putting on the scales Writing down new mass. Amount of sugar in solutionSolution concentration %Cup numberMass of five cubes before(Â ±0,05g)Mass of five cubes after (Â ±0,05g) 0g0%15,8g6g 6,8g6,37%25,1g5,2g 13,7g12,05%35,5g5,3g 20,5g17. 01%45,6g5,4g 27,4g21,51%55,5g5,3g Graph: While the concentration is from 0% to 6,37% the net mass gets bigger, later on from 12,05% to 21,51% the net mass gets smaller.When the concentration is from 0% to 6,37% the net mass change is positive, when from 17. 01% to 21,51% – negative. Conclusion: The potato lost more mass as it was submerged in bigger concentration solutions because the bigger concentration difference is, the osmosis will occurs more intensively. Evaluation: I think that laboratory work went pretty well, I managed to see the differences in potato mass change and make a conclusion of it. Next time I should write down origi nal numbers and not rounded ones to give more accurate results.

P3725 case 21 Essay Example | Topics and Well Written Essays - 1000 words

P3725 case 21 - Essay Example On the other hand, untreated periodontitis can lead to early tooth loss. According to Ere and Genco (2007), â€Å"periodontal disease is highly prevalent in older adults, affecting 34% of the American population ages greater than 30 years and it is severe in 13% .† Patient with certain genetic traits or systemic diseases such as diabetes, smokers, stress, medication, clenching, or grinding teeth suffer from increase susceptibility. Reducing gingivitis and destructive periodontal diseases among adults is one of the important oral health objectives since it entails proving good oral preventive instruction care. As a student, I want to contribute to the efforts aimed at decreasing prenatal disease care particularly with respect to the case of Mr. B. I have seen a number of patients with some periodontal disease. Such encounters have been very fundamental in broadening my knowledge and understanding on care related to such infections, a move that would be very critical in helping such patients. One of such cases is that of Mr. B who is 48 year-old male, divorced, and works 3-4 days a week far from home. Currently, he is serving as a salesperson. He happens to have been complaining of the appearance of the yellowing and stains teeth. Over the last three years, he has been to a dental specialist after every 4 months for checkups and cleaning. This patient clenches and grinds the teeth in the daytime and night. He does not floss and regularly uses hard tooth brush 3 times a week for approximately one minute with hydrogen peroxide and baking soda tooth paste. He has been smoking two packets of cigarettes per day and has not plan to quite any time soon. Also, he consumes four cups of coffee daily. The patient has type II diabetes und er control with medication. The last physician visit was for hyperthyroidism thyroid gland with medication. He strives to reach a

Personal Paper Essay Example | Topics and Well Written Essays - 500 words

Personal Paper - Essay Example They lived in a broken down shack. They slept on the floor, and they did not have any electricity or running water. My grandmother was the caretaker, while my grandfather supported the family. He worked in the tobacco fields. My mother’s sisters and brothers all pitched in to do all the chores. They had no specific roles. They all cleaned the house together, took turns sweeping the floor, and fetching water. My grandfather and his family finally migrated to New York in 1951. Upon relocating to New York, my family did not move into a Hispanic community, instead they moved into an African American community called Harlem, which is a predominately African American Community. It is believed my grandfather wanted to get away from the Hispanic community. It was very difficult for them due to the language barriers. The family did not speak any English except my grandfather. Upon entering school my mother, her sister’s and brother’s were all placed in the same grade, because they lacked the ability to speak the native language. The school gave them a bilingual teacher who taught them to speak the native language. She was also a big support to my mother’s family, and due to the school support, and the support of the community my mother’s family adjusted very well to their new environment. All of my aunts and uncles married, and soon branched out into different communities, and had children of their own. I was born and raised in a New York City Housing Project (NYCHA) called Jefferson, which consisted of a multicultural community. I resided in the home with my mother, father and five siblings. Despite my mother never obtaining an education she was very active within the community. She did voluntary work as a school Para Professional with special needs children, and my father worked in a garment factory. Most of the friends came from single-families households. Their main sources of income were either

Business statistics Essay Example | Topics and Well Written Essays - 250 words

Business statistics - Essay Example This is given that Professionals and Managers frequently are attentive to their measures level like mode, sums, and means. This is a way of communicating of the measure level and numbers use. In comparing of descriptive and inferential data, the two define the data variation in terms of the probability or dispersion distributions/patterns describing the data. This is where both rely on the same set of data. The only difference between the 2 is that inferential data aims to draw general conclusions about a big population (Richard, 69). This way its clear organizations look at results in many ways: quality, time, expenses etc. The dispersion learnt earlier helps to recognize the data information being tracked/measured. In order to decide of results and outcomes, we ought to understand the data variation or consistency (Richard, 44). This means data variation results to dissimilar results understanding. Descriptive statistics method of calculating data is for instance, function of Excel Analysis ToolPak function which produce salary data that is descriptive in statistics. The example of calculations in statistics is the Employee Salary Data set. In research, we categorize the collected data by the GEN1 (G variable) for females and males and then get each gender average and standard deviation for these variables in terms of age or other quantity measure (Richard, 78). It is possible to use for one gender descriptive and the functions of FX for (MEAN and STANDARD DEVIATION) for the other. The paper has looked at the numbers and measurement as well as descriptive and inferential data as a way of analyzing data collected. This way the paper has discussed how inferential data differs from the descriptive data where as seen, inferential depend on the data to draw general perspective of big populations. Lastly, the paper has viewed some research application of descriptive data in contrast to inferential

Case analysis Essay Example | Topics and Well Written Essays - 1500 words

Case analysis - Essay Example In St Amos Hospital, culture and ethics were closely related with the provision of extensive initiatives to employees. It is for this reason that absenteeism has never been a problem for the company despite the difficulties and the tension that characterize the specific sector. However, the problem of the missing linen proved to be the beginning for the decrease of the firm’s performance due to the measures introduced for its investigation. More specifically, because of the increase of shortages in linen, the hospital administrator, Paul Seay sent two memos to the night nursing director Jean McDuff. The first of these memos was rather general proposing just a few changes to the existed work framework (proposals included the observation of handling of linen and the report of any irregularity). However, the second memo was too difficult to be followed and as a result many of the employees working in the night shift were either resigned or asked to be removed to the morning shift . On the other hand, absenteeism that had never been a problem became frequent. In general, the performance of the hospital was radically decreased for the period followed the application of the second memo. It could be stated that the strategies proposed by the firm’s manager, specifically the hospital administrator, where not appropriate in accordance with the extension and the nature of the particular problem. This assumption can be supported by the fact that the application of the measures suggested by Paul Seay led gradually to the decrease of the employees’ performance specifically regarding the night shift in the above hospital. For this reason, the turbulences occurred in the organizational culture and the ethics applied throughout the specific organization could be regarded as a normal consequence of the measures proposed in order to face the problem of the shortage of linen. The firm’s

Texas Policy Report Term Paper Example | Topics and Well Written Essays - 750 words

Texas Policy Report - Term Paper Example Governor Rick Perry signed the Texas bill 5 during a special session. Rick Perry convened the special session after Senator Wendy Davis conducted a filibuster in an attempt to interfere with signing of the abortion bill. Rick Perry signed the bill in a ceremony attended by various media groups, lobbyists and legislators. Perry and other supporters of the abortion bill had believed that unborn children experience immense pain during abortion. Governor Perry had proposed the abortion bill on May 27, 2013 though it became unsuccessful in regular senate sessions. However, Wendy and other activists argued that illegalizing abortion would had fatal consequences to the mother. Wendy explained her protest through her experience where she discussed abortion case of her daughter (The State of Texas 1). Wendy had tried several times to stop law provisions that restrict abortion including 2012 debates. She was especially concerned about part of abortion bill that banned abortion after 20 weeks of pregnancy. Consequently, during the special session when the Perry was to sign the abortion bill in June 25, 2013, Wendy Davis reported to the media that she would conduct a filibuster. The filibuster would aim at preventing final process of adopting abortion bill. Wendy attracted social media debate following her emotional speech where she discussed heart-rending disclosures about her pregnancy experiences. However, Governor Perry had promised citizens six months before the 25 June 2013 session that he would sign laws against abortion. Perry had stated that unborn babies deserved the legal rights to sound health besides constitutional protection. He had believed that abortion bill would form the foundation on Texas culture of respect for life. House bill 2 signed by Governor Perry had provisions that bans abortion after 20 weeks of pregnancy. In addition, House of Bill 2 demands that clinics that perform abortion be of similar health