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Comparison of CNC Machines Based on the Development Perspectives of Plastok OÜ
No full textKäesoleva lõputöö eesmärgiks oli välja selgitada, milline on ettevõtte edasine pinkide soetamise strateegia. Töös on käsitletud kahe CNC-pingi võrdlust lähtuvalt Plastok OÜ arengu perspektiividest. Töö käigus vaatles autor Euroopas valmistatud Kimla BPF-2141 pingi ja Hiinas
valmistatud Step More SM-2131 pingi tööd viie tööpäeva jooksul. Analüüsides vaatluse käigus
saadud mõõteandmeid, pinkide tehnilisi andmeid ja autori poolt teostatud tasuvusarvutust, leidis autor vastused järgnevatele küsimustele:
1. Millised on suurimad seisakute põhjused?
Autori poolt teostatud vaatluse käigus saadud mõõteandmete põhjal on pinkide suurimad seisakute ajad põhjustatud üleminekutega seotud operatsioonide tõttu. Need tulenevad ettevõtte tootmise iseloomust, kuna korduvaid detaile peaaegu, et ei olegi ning päevas tehakse valmis mitmeid tellimusi erinevate materjalidega. Märkimisväärne tootliku aja kadu tuli ka joonise tegemisele ja programmeerimisele kulunud seisakutest.
2. Milline pink oleks ettevõttel kasulikum järgmiseks soetada?
Pinkide võrdlemisel said otsustavateks asjaoludeks euroopa pingi suuremad töökiirused (maksimum spindli kiirus, maksimum liikumiskiirused telgedel), suurem automatiseeritus (nullpunktide positsioneerimine, telgede ristseisu kalibreerimine ja tööriistade vahetamine) ning pingi parem konstruktsioon, mis tagab pingi stabiilsuse ja töökvaliteedi. Autori poolt teostatud tasuvusarvutusest selgus, et euroopa pingi suurem soetusmaksumus tasub ennast ära maksimaalselt viie aastaga. Võttes arvesse eelpool väljatoodut ning euroopa pingi poolt toodavat aastast lisa müügitulu (40 248 eurot), on autori hinnangul ettevõttel kasulikum soetada järgmiseks pingiks Euroopas valmistatud CNC-pink Kimla BPF-2141.
Lõputöös püsitatud küsimustele vastuste leidmise käigus tulid välja olulised nüansid, mis aitavad ettevõttel otsustada milliste kriteeriumite alusel uut pinki valida. Autori poolt teostatud analüüsi abil mõistavad Plastok OÜ töötajad paremini, kuidas tehakse tööd ettevõtte tootmisseadmetega ning millised on potentsiaalsed parendamiskohad. Lõputöös tehtud analüüs on abiks ka Evocon’i juurutusprotsessi juures, aidates mõista pingi operaatoritel OEE mõõtmise vajalikkust. Ettevõtte juhid, kes asuvad uut pinki valima, saavad kasutada käesolevas lõputöös tehtud analüüsi tulemusi lähteülesandena uue tootmisseadme soetamisel.The aim of this bachelor’s thesis Comparison of CNC Machines Based on the Development Perspectives of Plastok OÜ was to find out what is the company's future strategy for acquiring CNC machines. The thesis deals with the comparison of two CNC machines. The author observed the work of the European-made Kimla BPF-2141 machine and the Chinese-made Step More SM-2131 machine during five working days. After analyzing the measured data obtained during the observation, the technical data of the machines and the profitability calculation performed by the author, the following questions were answered:
1. What are the biggest causes of downtime?
Based on the measured data obtained during the observation carried out by the author, the largest machine downtimes are caused by operations related to changeovers. They arise from the nature of the company's production, as there are almost no repetitive details and several orders with different materials are filled daily. A significant loss of productive time also came from downtime spent on sketching and programming.
2. Which machine would be more beneficial for the company to acquire next?
When comparing the machines, the higher working speeds of the European machine (maximum
spindle speed, maximum movement speeds on the axes), greater automation (positioning of zero points, calibration of the cross position of the axes and changing of tools) and the better
construction of the machine, which ensures the stability and work quality of the machine, became the decisive factors. The profitability calculation performed by the author revealed that the higher acquisition cost of the European machine pays for itself in a maximum of five years. Taking into account the above and the additional annual sales revenue generated by the European machine (40,248 euros), the author's opinion is that, it is more beneficial for the company to purchase the CNC machine made in Europe, the Kimla BPF-2141, as their next CNC machine.
During the process of finding answers to the questions raised in the thesis, important nuances
emerged that help the company decide on the basis of which criteria to choose a new machine. With the help of the analysis carried out by the author, the employees of Plastok OÜ better understand how work is done with the company's production equipment and what are the potential areas for improvement. The analysis made in the thesis is also helpful in the Evocon implementation process, helping machine operators understand the necessity of measuring OEE. The managers of the company, who are going to choose a new machine, can use the results of the analysis made in this thesis as a starting point for the acquisition of new production equipment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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