How to write apa paper
Topics To Make A Research Paper
Tuesday, August 25, 2020
Answer question Essay Example | Topics and Well Written Essays - 250 words - 13
Answer question - Essay Example For the examination to have solid discoveries, the creators gave remittances to different wellsprings of variety in business including contrasts over the chains. To get such variety, the fundamental conditions utilized were as shown beneath. The investigation found that 18 percent expansion in the New Jersey the lowest pay permitted by law was anticipated to lessen work at quick nourishments outlets by 0.4-1.0 representatives per store (David and Alan, 1994). Furthermore, the investigation uncovered that even in neighborhoods, rose quicker at the stores that expanded wages because of the lowest pay permitted by law. Thirdly, the paper found that relative value changes assumed a job inside the cheap food industry as the consequence of raising the lowest pay permitted by law. One of the perspectives that make this investigation to have irrational outcome is that when the lowest pay permitted by law is raised, low aptitude laborers hold their employments. Moreover, it is one of the methods of achieving insignificant way of life. David, C and Alan, K. (1994). Least Wages and Employment: A Case Study of the Fat-Food Industry in New Jersey and Pennsylvania. The American Economic Review, Volume 84, Issue 4 (Sept., 1994),
Saturday, August 22, 2020
Pc Hardware Servicing Course Structure Essay Example
Pc Hardware Servicing Course Structure Essay Apply Quality Standards |Applying of Quality Standards |Assess nature of got materials. |6 hrs. | |1. . Survey own work. | |6 hrs. | |1. 3. Approve oneââ¬â¢s work for quality | |improvement. |8 hrs. | |Use of Hand Tools |2. Utilizing Hand Tools |2. 1. Plan and get ready for assignments to be |6 hrs. | |undertaken. | |2. 2. Get ready hand apparatuses. | |20 hrs. | |2. 3. Utilize proper hand instruments and | |test gear. |38 hrs. | |2. 4. Keep up hand instruments. | |16 hrs. | |100 hrs. |Grading Period |Unit of Competency |Module Title |Learning Outcome |Nominal Duration | |2. We will compose a custom paper test on Pc Hardware Servicing Course Structure explicitly for you for just $16.38 $13.9/page Request now We will compose a custom exposition test on Pc Hardware Servicing Course Structure explicitly for you FOR ONLY $16.38 $13.9/page Recruit Writer We will compose a custom exposition test on Pc Hardware Servicing Course Structure explicitly for you FOR ONLY $16.38 $13.9/page Recruit Writer Utilization of Hand Tools |2. Utilizing Hand Tools |2. 4. Keep up hand apparatuses. |10 hrs. | |2nd | | | |Terminate and Connect Electrical Wiring and |3. Ending and Connecting of|3. 1. Plan and get ready for end |40 hrs. | |Electronic Circuit |Electrical Wiring and Electronics|or association of electrical wiring and| | |Circuit |electronic circuit. | |3. 2. End or associate electrical | |wiring and electronic circuit. |50 hrs. | |100 hrs. | |3rd | |3. End and Connect Electrical Wiring |3. Ending and Connecting of |3. 2. End as well as interface |18 hrs. | |and Electronic Circuit |Electrical Wiring and Electronics|electrical wiring and electronic | |circuit. | |3. 3. Test end/associations of| | |electrical wiring and electronic |82 hrs. | |circuit | |100 hrs. | |Grading Period |Unit of Competency |Module Title |Learning Outcome |Nominal Duration | |4th | |3. End and Connect Electrical Wiring |3. Ending and Connecting of |3. 3. Test end/associations of|10 hrs. | |and Electronic Circui t |Electrical Wiring and Electronics|electrical wiring and electronic | |circuit | |Install Computer System |Installing of Computer System |4. 1. Plan and get ready for |20 hrs. | |installation. | |4. 2. Introduce gear, or gadgets and|50 hrs | |system. | |4. 3. Lead approval and testing. |20 hrs. | |100 hrs | Year Level |Third Year | |Grading Period |Unit of Competency |Module Title |Learning Outcome |Nominal Duration | |1st | |Install Computer Network |Installing of Computer Network |1. 1. Plan and get ready for |40 hrs. | |installation. | |1. 2. Introduce quipment/gadget/|40 hrs | |system. | |1. 3. Direct approval and | |testing. | |20 hrs. | |100 hrs. | |2nd | |Diagnose and Troubleshoot Computer System |Diagnosing and Troubleshooting of |2. 1. Figure plans and |20 hrs. | |Computer System |prepare for indicative | |procedures for PC | |systems. | |2. 2. Recognize PC flaws | |and different deformities. | |2. 3. Supplant and give |38 hrs. | |remedies for the flawed | |computer parts. | |2. 4 Test fixed PC | |system. |20 hrs. | | | |22 hrs. | |100 hrs. | |3rd |3. Design Computer System and Network |Configuring of Computer System and|3. 1. Mastermind design and get ready |30 hrs. | |Network |for arrangement task. | |3. 2. Design the PC | |system and arrange. |70 hrs. | |100 hrs. | |4th |3. Arrange Computer System and Network |Configuring of Computer System and|3. 2. Design the PC |66 hrs. | |Network |system and organize. | |3. Break down and give a shot | |configured PC framework and | |network. |34 hrs. | |100 hrs. | Year Level |Fourth Year | |Grading Period |Unit of Competency |Module Title |Learning Outcome |Nominal Duration | |1st | |Maintain Computer System and Network |Maintaining of Computer System |1. 1. Plan and get ready upkeep |100 hrs. | |and Network |procedures. | |2nd | |Maintain Computer System and Network |Maintaining of Computer System |1. 1. Plan and get ready upkeep |6 hrs. | |and Network |procedures. | |1. 2. Keep up PC framework and | |network. | |94 hrs. | |3rd | |Maintain Computer System and Network |Maintaining of Computer System |1. 2. Keep up PC framework and |94 hrs. | |and Network |network. | |1. 3. Investigate and test PC framework |6 hrs. | |and arrange. | |4th | |Maintain Computer System and Network |Maintaining of Computer System |1. 3. Review and test PC framework |100 hrs. | |and Network |and arrange. |
Sunday, August 2, 2020
It All Started with a Sound Board
It All Started with a Sound Board [by Harrison Bralower 11] It started with a sound board. When I was in eighth grade my class went to the local high school to see a production of Man of La Mancha and I got seated right behind the sound board. The show was fantastic but I couldnt take my eyes off the two guys mysteriously lit by the glow of the microphone rack who constantly shuffled their hands across the table. I thought it was so cool that everything on stage was actually a result of a few kids scrambling around behind the scenes. It was then that I decided I wanted to do theater in high school. So after four years of high school theater I was pleased to find that MIT had a very strong theatrical arts program that anyone could take part in. From novices who are just getting started to experienced people looking to learn more, theres always a place where you can jump in and help a production out. Monica Kahn 10 personifies Marijuana in Dramashops 2007 One Acts festival. The plays are student-written, directed, and produced. Photo / Andrea Robles The Tech One of the easiest ways to do this is just by taking classes. MITs Music and Theater Arts (MTA) department offers classes in stagecraft, lighting design, script analysis, acting, set design, voice, and costume design among many other offerings. In addition to taking for-credit classes, you can do for-credit practicum work with Dramashop, the actual production wing of MTA. Dramashop puts on shows year-round, including a One Acts festival in the fall and a hectic IAP show that involves eight-hour rehearsal days and a very sped-up production schedule. I stage managed this years One Acts and it was a fantastic experience. I learned more about technical theater just by listening to and talking with the department faculty. I also met a lot of new people from all over the areapeople from MIT, Wellesley College, and Emerson College. This IAP Im working with Dramashop again, this time as a sound assistant/operator for the show Suburbia. Its about a bunch of twentysomethings with no direction reuniting with a former classmate who has made something of himself and the impact of his return on everyone else. Were planning on fights, flinging food around, and live bands just to name a few details. The only hurdle is that we have to coordinate and rehearse the entire show during January and four weeks is not a lot of time to get a production up and running. If you like to sing, dance, act, and tech with people your own age theres also a few student theater groups at MIT. The Musical Theatre Guild (MTG) puts on four musicals a year from fan favorites to new, inventive shows (like the infamous Star Wars musical). The Shakespeare Ensemble puts on several shows a year and also hosts scene nights and workshops for anyone looking to do a little work on the side or just learn something new. And the Gilbert and Sullivan Players (GSP) perform a wide range of shows from the eponymous pair. Theres way more theater people here than youd expect to find at a place like MIT and theyre all awesome people to work with and talk to. Its easy to get involved and its a great way to meet new people and get some fun memories out of your time here. Got a question about theater (or any of the other arts) that I havent covered here? Drop me a line in the comments section.
Saturday, May 23, 2020
Student Loans Over The United States - 1483 Words
College students across the nation suppress a shudder when the phrase is uttered. They try to push it to the back of their mind, to save the problem for another day. Sadly, it cannot be ignored forever. Student loans over the United States have been becoming more frequent and increasing in size for years. According to M. Swig, Hickey, and S. Swig, there are now 41 million Americans burdened with having to pay student loans back. While one may question if taking out a student loan in the thousands is worth it, one should consider today s society. To most people, college is the only option. Parents, families, and neighbors almost force it upon the young adults because they believe itââ¬â¢s the only way for them to be successful. Much of the nation views a higher education as the key component in an individual s future job, wealth, and therefore general happiness. It is almost to the point where not attending would be comparable to breaking a social norm. Another scary statistic is how the price of tuition has risen in the last decade. According to Johnson, Ostern, and White in The Student Debt Crisis, ââ¬Å"in the past three decades, the cost of attaining a college degree has increased more than 1,000 percent.â⬠This leaves many students in a conundrum. Unless a person is born into a wealthy family, they will not have the means to pay for any form of a higher education. This leaves many with the burden of taking out a student loan. There are many different types of loans available,Show MoreRelatedStudent Loan Debt Is A Negative Effect On The Future1349 Words à |à 6 PagesAfter the United States ââ¬ËGreat Recessionââ¬â¢ in 2008, many onlookers have been searching for other aspects of the economy that may eventually present a bubble similar to that of the housing market. It does not take long to locate a potential hazard as the cost of tuition has risen approximately 26% over the course of the last decade (ââ¬ËTuition and Feesââ¬â¢). The co nsequence of this increased tuition is having a negative effect on the future that most graduates try to obtain once they complete school. SomeRead MoreThe Average Cost Of Tuition1684 Words à |à 7 Pagesgraduates will pay their substantial student loans. While seventy percent of college students are forced to take out student loans thereââ¬â¢s no question the majority of graduates will be paying for their education over a long period of their life. Student loan debt is also at an all time high in the United States, with a staggering $1.4 trillion dollars of debt solely for student loans. Current presidential candidates are campaigning to lower college tuition and student loan debt, while others are campaigningRead MoreStudent Debt Is A Form Of Debt1576 Words à |à 7 PagesStudent debt is a form of debt that owed by an attending, withdrawn, or graduated student to a lending institution. The lending is often of a student loan, but debts will be owed to the school if the studen t has dropped classes and withdrawn from the school. Withdrawing from a school, especially if a low or no-income student has withdrawn with a failing grade could deprive the student of the ability of further attendance by disqualifying the student of necessary financial aid. Student loans alsoRead MoreStudent Loan Debt Of The United States1746 Words à |à 7 Pagesto other countries, student loan debt in the United States is skyrocketing due to over-inflated tuition costs, dismal grant/scholarships availability and lack of beneficial repayment programs. Body Student loans are becoming an increasingly heavy burden for their borrowers in the United States. In a personal interview conducted on October 20th, 2015, a close personal friend, Cory Hays, and the sister of the author, Melissa Korpela, were interviewed regarding their student loan debts and status ofRead MoreStudent Loan Debt: Is it worth it?1364 Words à |à 6 PagesStudent Loan Debt: Is it worth it? à à à à à à à à à à à Many high school students are beginning their senior year and have already started to stress about how they will pay for their higher education. Although many students will have scholarships and financial aid, a lot more will struggle to pay for schooling and will have to take out multiple student loans. Many people wonder if higher education is worth the debt the country and the students are in and it is, however, there are alternatives. à à à à à à à à à à à Read MoreEducation : A Way Of A Better Life?1615 Words à |à 7 Pagesmost important thing to have in life is an education. The thing about getting an education is that it costs money, and one of the main ways to pay for a higher education in the United States is to take out student loans. Although student loans can be helpful in getting an education they can also be very burdening. Even as student debt is being seen as harmful to several individuals, there are people in the world that are benefitting from the acquiring of this unique type of debt. The sad reality thatRead MoreHow Student Loans Have Affected The Cost Of Tuition964 Words à |à 4 Pagescollege student could attend a public four-year university for $2,500 and a private university for a little over $5,000. Although, most of these universities are offering the same mediocre education from the last three decades; the cost of tuition has more than tripled for public universities and for private universities, it has gone up a staggering 85%. Canada holds an average educational cost of 5,974 and England follows with an estimated average cost of 5,288. In spite the tuition in the United StatesRead MoreIs Forgiving Student Loan Debt A Good Idea?972 Words à |à 4 PagesAnalysis of Is Forgiving Student Loan Debt a Good Idea Many people would love to have their student loans debt forgive but do not believe it will happen. So Kayla Webley decided to write an article about student loan forgiveness, at the time Webley wrote the article she was the education correspondent for Time magazine. Now she is currently a staff writer for the same magazine. In her article, she claims that the student loan dilemma that is facing a lot of Americans is a problem for your countryRead MoreFinancing For Loan And Debt Crisis1269 Words à |à 6 Pagestrillion, and of that, student loans account for $1.08 trillion and that number is growing larger and larger every year (Hiltonsmith, Robert). A large portion of the population undoubtedly feels the burden of these statistics. Seven out of every ten college seniors has reported having to take out one or multiple student loans so that they can to afford to go to college (Hiltonsmith, Robert). The results of this outstanding amount of debt does not just affect the United Stat es negatively for the obviousRead MoreStudent Loan Crisis1592 Words à |à 7 PagesStudent Loan Crisis Beginning in the 1960ââ¬â¢s the distribution of federal and non-profit funds have given students all over the United States the opportunity to pursue post-secondary educations. Although this method has given students the ability to go to college financially, the majority of the students are not able to pay the money back when finished causing debt. Currently students in the United States owe more than $1 trillion dollars worth of federal and private student loans. Surprisingly this
Sunday, May 10, 2020
The Presence of Symbolism Throughout The Black Cat and...
Through out Edgar Allen Poeââ¬â¢s career his stories and works of art have all carried their own distinctive independence, but one of the very few things that most stories by Poe had in common was the literary element of symbolism. Symbolism is the practice of representing things by symbols, or of investing things with a symbolic meaning or character. In Poeââ¬â¢s works such as ââ¬Å"The Black Catâ⬠and ââ¬Å"The Cask Of Amontilladoâ⬠Edgar illustrates the mental state of his characters through the use of symbolism. In the story ââ¬Å"The Black Catâ⬠the narratorââ¬â¢s psychological state is portrayed through the signs or symbols of the white fur, the cat, its eye, and the wall. In the second story, ââ¬Å"The Cask Of Amontilladoâ⬠irony of fate and identity is signifiedâ⬠¦show more contentâ⬠¦Although Fortunato has insulted and disrespected Montresor, the arms suggests that he will ultimately crush him. In addition to this, the family motto Nem o me impune lacessit, which means no one wounds me with impunity, reveals Montresors obligation avenge the disrespect, even if it means death. Lastly, the amontillado is a symbol of pride. It is the single, most important factor in luring Fortunato into a fateful trap. By Montresor asking him to test the wine, he is building up Fortunatos arrogance and confidence. The amontillado helps to bring out Fortunatos pride. In his attempt to boost his pride and show off wine tasting abilities, he enters the catacombs, and literally enters his death. The Cask Of Amontillado contains numerous symbols, including their costumes, names, coat of arms, motto, and the amontillado, which help to reflect physiological state of the two characters. Poe uses all of these symbols to drive home the overall message of the dangers of arrogance and pride. ââ¬Å"The Black Catâ⬠on the other hand is a story where symbolism can be seen as use for the description of the narratorââ¬â¢s condition. As long as I can remember, a black cat has always been symbolized for bad luck or an evil omen. In this story itââ¬â¢s used a figure to illustrate the narratorââ¬â¢sShow MoreRelatedEdgar Allen Poe s The Cask Of Amontillado1528 Words à |à 7 PagesEven though emotional problems in Edgar Allen Poe s life contribute greatly towards the gothic themes of his work, conflicts of love and hate as well as self and the alter ego, have influenced his writing on death and delusional characters. Though there are many notable writers and poets who contributed to the field of English literature in the 19th century, Edgar was among those who remained on the sidelines despite their extraordinary talent. In all of Poe s works, the themes of emotional painRead More Poeââ¬â¢s Lifeâ⬠¦ At the Tip of a Pen Essay2201 Words à |à 9 Pageswork s is derived from the life and the experiences of the creator. For some, these tales become stories and those stories become novels, but for one man it meant so much more. The works of Edgar Allan Poe became his life; he expressed every feeling and every moment of his existence through ink and paper. Poe involved his entire life in his writing, leaving no element of the story untouched by his trademark of a past. His work became so unique and unorthodox, yet it did not lack the attention itRead MoreEdgar Allan Poe : A Literary Catalyst2302 Words à |à 10 PagesEdgar Allan Poe: A Literary Catalyst Edgar Allan Poe created a new age of poem and prose though his articulate calculation of production and fantastic usage of poetic effect. His way of creating a work was to mathematically draw the poem from the atmosphere or effect backwards, running this idea throughout the piece. Many people consider Edgar Allan Poe as one of Americaââ¬â¢s greatest authors, but still question that without Poe, the unveiling of the human propensity represented in poetryRead MoreANALIZ TEXT INTERPRETATION AND ANALYSIS28843 Words à |à 116 Pagesof Cain a legacy of guilt that the outcast Brand shares with his Biblical counterpart. One must also, however, be alert to names used ironically which characterize through inversion. Such is the case with the foolish Fortunato of Poeââ¬â¢s The Cask of Amontillado, who surely must rank with the most unfortunate of men. 2. CHARACTERIZATION THROUGH APPEARANCE. Although in real life most of us are aware that appearances are often deceiving, in the world of fiction details of appearance often provide essential
Wednesday, May 6, 2020
Mic 206 Guidelines for Unknown Investigation Lab Report Free Essays
MIC 206 Guidelines for Unknown Investigation Lab Report General Considerations: A. Papers must be typed, written in past tense, and in third person. (-50 if not typed) B. We will write a custom essay sample on Mic 206 Guidelines for Unknown Investigation Lab Report or any similar topic only for you Order Now Paper Structure: Each section is to be headed with the appropriate heading. C. Format and Style 1. Format: a. Face Page: The face page should contain the title of the experiment, the author of the report, class section time, date submitted. (1. 5 points) b. Page Format: (1. 5 points) 1. One-inch margins 2. Last name page number as the header 3. Double spaced 4. Section headings . Other considerations: 1. Tables, charts, and figures should be clearly labeled with captions. Ex. Figure 1/Table 1. (2 points) 2. ALL genus and species names must be italicized and the genus name must be capitalized. The first time that a genus name is used, write it out in full (Pseudomonas aeruginosa). After that, one letter abbreviations may be used (P. aeruginosa). (3 points) D. Plagiarism: Remember that you may quote another personââ¬â¢s work, or even paraphrase it as long as you give credit and cite the work you are quoting, paraphrasing, or referring. -50 if plagiarism occurs) 3. Parts of a Scie ntific Paper: A. Abstract: This appears first in the paper, but it is the last section written. In the Abstract: (1) state the major objective(s) and scope of the experiment, (2) briefly describe the methodology used, (3) summarize the results, and (4) state the major conclusions. (3 points) B. Introduction: In this section, you should provide general background information on the subject to aid the reader. This can be followed by a very brief description (1-2 sentences) of the problem that was investigated. Every report must include a clearly stated hypothesis. A hypothesis is a statement of what may or may not occur under defined conditions. Your hypothesis must be clearly (readily identifiable) presented in this section of your report. Remember that a hypothesis does not have to be correct, just testable. (5 points) C. Materials and Methods: For this section, you should merely cite your laboratory manual sections and/or pages used. Any changes made to the procedure should also be noted in this section. Finally, any changes made to the directions outlined in this manual must be stated in the materials and methods section. For instance, if the directions stated that you should incubate your sample at 37(C for 1 hour, and you incubated your sample at 25(C for 30 minutes, you must note the deviation. If you use any procedures NOT in the lab manual, describe them fully and cite them. Do not do anything more than listed above for this section. (2 points) D. Results: You must describe what you did to obtain the data that you are presenting in this section (If in doubt ââ¬â refer to a journal article). You should describe the data in such a manner that if the reader chose not to look at the figures, tables or graphs, they could still understand your data. The data must be summarized in figures, tables or graphs, which must be clearly labeled and referred to specifically by name when they are being discussed. You must present both your raw data and calculated results. For the calculated results, a sample calculation must be provided so that we can determine how you obtained the calculated values. When graphs are used, be sure that both axes are labeled correctly. Remember that the dependent variable is ALWAYS presented on the vertical axis. As a rule, the intersection of the X- and Y-axes should be the zero point. The spacing between time points should be proportional to the elapsed time. DO NOT USE BAR GRAPHS, they are not appropriate in this course. In the case of differential tests, you must describe in general terms what constitutes a positive and negative result. That way we can determine whether you are interpreting your results correctly. All data MUST be reported. Deleting data to suite your hypothesis is the same as inventing data in order to suite your hypothesis. If there are data that appear to be erroneous, you may choose not to use those data or datum, but you must still include it in the results and justify your decision not to use it. Finally, if an experiment fails and you have no data, you may obtain results from a classmate or your instructor. You cannot receive full credit for a report that has no data analysis. If you use outside data, you must state the source of the results. (7 points) E. Discussion: This is the only section in which the use of the first person is acceptable. Remember, in your Discussion, you do not reiterate your results, rather you interpret them and discuss their meaning. Present a discussion of your results as it relates to your hypothesis. Bring attention to data that support your hypothesis. You must also bring attention to data that contradict your hypothesis and provide possible explanations for why the data do not correlate with your hypothesis. It is typically easier to write a discussion when your data do not support your hypothesis. However, that does not mean you should create a hypothesis that will purposely not be correct. You should also compare and contrast your results with other work in the field; do your results and interpretations agree or disagree with other members of your class? outline considerations for the Discussion Section: 1. State you conclusions clearly and boldly 2. Summarize the supporting data (results) for each conclusion you draw. 3. Include the following in the discussion: a. Normal Microbiota of your bacteria b. Bergeyââ¬â¢s Group Classification/ Identification c. Does your bacteria have a Role in Disease d. Does your bacteria have a Role in Biotechnology e. One unique fact, not previously reported above, that you found interesting f. What communal relationship does your bacteria have with our environment or our bodies. 4. End your paper with a short summary or conclusion regarding the significance of the experiment. (15 Points Discussion section) F. Bibliography: In writing your Introduction, Mat Meth, and Discussion, you will need to support your assertions and contentions with citations from the literature. You may cite such sources as journal articles, textbooks, the lab manual, an encyclopedia, a dictionary, or any other useful sources. Be very wary of using websites ââ¬â anyone can write anything and put it on a website. There is no minimum or maximum number of references required for any given report. Citations and References shall be in American Society of Microbiology (ASM) style. (-25 points if you do not properly use ASM style) Obtained isolated colonies on MAC plate, from original unknown sample (1 point) Obtained isolated colonies on CAN/PEA plate, from original unknown sample (1 point) Note: isolated colonies must have been obtained from quadrant streaking original unknown mixed culture tube. If a second culture or a control culture was given to you, after failing to get isolated colonies from your original mixed culture and you observed isolated colonies at that point, the 1 point is not earned. ) Identified Gram Negative bacteria: (2. 5 points) Identified Gram Positive bacteria: (2. 5 points) Report is written free of grammatical or mechanical errors as determined by the TA. (3 points) Source: Stout, V. MIC 302 Report Writing Guidelines. Arizona State University How to cite Mic 206 Guidelines for Unknown Investigation Lab Report, Essay examples
Thursday, April 30, 2020
Plastics Engineering Essays - Business, Manufacturing,
Plastics Engineering Injection Molding Most people have never heard of injection molding, however the products that are produced through this process are as common as a toothbrush, a compact disk, or even drinking glasses. Injection Molding is one of the principal processes used in converting plastics into useful products. An injection molding machine can be large or small but work through the same general process. The machine heats a thermoplastic material that in its pre-processing state is pelletized or granular, to a liquid-like"flowable" state. It then injects the melted plastic into a mold that is used to create the desired shape of the product. The plastic in the mold is then allowed to cool and removed form the mold by an ejector system. Different raw plastics materials can be used in the injection molding process. Most commonly injection molding machines provide processing for phenolics, melamine, silicone, elastomers and polyester. These materials can be numerous colors and can be used for making the various products depending on what characteristics like elasticity. flexibility and hardness are needed. The injection molding machine has two main components the injection unit and the clamp unit. The injection unit melts and injects the materials. There are usually about eight main parts that make up the injection unit, and they are the barrel, the nozzle, the screw and non return valve, heater bands, a motor to rotate the screw, and a hydraulic cylinder to move the screw forward and backward. Control systems are used for temperature regulation, and the timing of the screw rotation and injection strokes. The screw consits of three main sections the metering zone, the transition zone and the feed zone. The feed zone makes up about 1/2 the total length of the screw. It has deep flights and is where the pellets first enter the screw. The transition zone is about 1/4 the length of the screw and has flights that are closer together to compress the pellets and aid in the melting process. The metering zone makes up the last portion of the screw mechanism and is where any final melting of the pellets occurs before the pellets pass through the non return valve and nozzle into the mold. The Clamping unit opens and closes the mold and ejects the parts. The two most common methods to generate clamping forces are direct hydraulic clamps and toggle clamps that are both actuated by hydraulic cylinders. In addition to those parts most injection molding machines also have a hydraulic pump and resivoir. Safety is a very important aspect of injection molding so most injection molding machines are equipped with safety devices. These devices can be mold closing safety systems, purge guards, and rear door systems. Mold closing systems are required to have a mechanical drop bar, electrical interlocks and hydraulic interlocks which all help protect the operator from injury. The actual injection molding process consists of 5 basic steps: 1. The mold closes. 2. The screw moves forward and forces the melted material into the mold 3. the screw maintains pressure through the nozzle while the plastic is cooled. 4. The timers stop injection pressure and the screw turns to draw fresh material 5. The mold opens and ejector pins remove the molded part. All these steps can also be grouped in a time cycle being: fill time, pack time, cooling time, and dead time. There are advantages and there are disadvantages to injection molding. Some of the advantages are that the surface finish can be controlled to make any texture, metal inserts can be used to make things like screwdrivers, and with thermo plastics the waste material can be ground and used again. There are also disadvantages like the high cost of the molds and that the molds are to expensive for just short product runs. Through advances in injection molding plastics are becoming more popular and are being used to produce a wider variety of products.
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