1,721,676 research outputs found
Cleanroom suitability of equipment: Assessment methodology according to 14644-14 and its verification
No full text9 S. + 30 FolienWhen performing manual handling steps, operators generate and emit varying quantities of contamination in an uncontrolled manner. To avoid the high risk of cross-contamination in cleanroom environments associated with these processes, an ever increasing number of these steps are being automated. In order to prevent products that have to be kept clean from becoming contaminated, it is therefore essential to know about the emission behavior of the respective machinery used in areas with controlled cleanliness levels. The most important type of contamination that affects all cleanroom environments is airborne particulate contamination, as it is defined in ISO 14644-1. The recently published draft ISO/DIS 14644-14:2014-10 describes a method for determining airborne particle emissions from equipment during typical operation. By interpreting these measurement results, cleanroom equipment can be assessed for suitability for use in clean controlled environments. On the one hand, this recently-defined method for assessing equipment enables hardware systems/machinery to be compared when used in typical modes of operation. In addition, the method allows areas of equipment where high quantities of particles are emitted to be identified. This helps to localize such sources of contamination and gives manufacturers the opportunity to optimize their equipment appropriately if they would like to do so. On the other hand, the procedure described in ISO/FDIS 14644-14 also gives an indication in which air cleanliness environments classified according to ISO 14644-1 the equipment can be used
Aktuelle Entwicklungen und neue Themenschwerpunkte der ISO 14644
No full textDie Normenreihe ISO 14644 ist eine Norm für Reinräume und zugehörige Reinraumbereiche. Das Regelwerk hat sich in den letzten Jahren aber zu weit mehr als einer Definition von Grenzwerten für Luftreinheitsklassen entwickelt. Die aktuelle Normungsarbeit beschäftigt neben dem klassischen Aspekt partikulärer, luftgetragener Kontaminationen mittlerweile auch mit chemischen Kontaminationen (luftgetragen/sedimentiert), biologischer Kontaminationskontrolle, der Bewertung und Auswahl von Reinigungsverfahren sowie der Eignung von Betriebsmitteln und Materialien für den Reinraum
PENGUKURAN PARTIKEL DI CLEANROOM TFME POLITEKNIK NEGERI BATAM MENGGUNAKAN STANDAR ISO 14644-1
Get PDFElectronics Tecnology is currently developing very rapidly. Computational capabilities that continue to increase are accompanied by a decrease in the size of the electronic components used on a chip or IC (Integrated Circuit). The size of the components that have reached nanometers makes the components very sensitive to impurities in the form of particles. A special fabrication place in the form of a cleanroom is needed so that the number of impurity particles can be controlled and the damage caused by impurity particles on the product can be reduced. One of the standards used to classify a cleanroom and measure the particles in it is ISO 14644-1. In this study, particle measurements were carried out in accordance with ISO 14644-1 standards to measure the number of particles in the TFME cleanroom. The measurement results classify the cleanroom in TFME into ISO Class 7. This is consistent with the initial TFME cleanroom design, meaning that the particle filtration system is still in a good condition.Teknologi dunia elektronika pada saat ini berkembang dengan sangat pesat. Kemampuan komputasi yang terus meningkat diiringi dengan semakin berkurangnya ukuran komponen elektronika yang digunakan pada sebuah chip atau IC (Integrated Circuit). Ukuran komponen yang telah mencapai nanometer menyebabkan komponen sangat sensitif terhadap pengotor dalam bentuk partikel. Tempat fabrikasi khusus dalam bentuk cleanroom diperlukan agar jumlah partikel pengotor dapat dikontrol dan kerusakan akibat partikel pengotor pada produk dapat dikurangi. Salah satu standar yang digunakan untuk mengklasifikasi cleanroom dan mengukur partikel di dalamnya adalah ISO 14644-1. Pada penelitian ini dilakukan pengukuran pertikel sesuai dengan standar ISO 14644-1 untuk mengukur jumlah partikel di dalam cleanroom TFME. Hasil pengukuran mengklasifikasikan cleanroom di TFME sesuai dengan ISO Class 7 yang berarti sistem penyaringan partikel masih bekerja dengan baik
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
Classification of air cleanliness by particle concentration according to ISO 14644-1
Get PDFThis article is the fifth of a short series of extracts from Bill Whyte's new book Cleanroom Testing and Monitoring. Chapter 12, Classification of air cleanliness by particle concentration according to ISO 14644-1, is reproduced here with the kind permission of the author, Bill Whyte, the publisher, Euromed Communications, and the owner of the copyright, the Cleanroom Testing and Certification Board – International (CTCB-I). The previous chapter, Chapter 11, Airborne particle counting with an LSAPC, was published in CACR49. The objective in publishing these extracts is to give readers a flavour of the content and depth of the book which is recommended as a comprehensive textbook and an essential reference for cleanroom managers, cleanroom test engineers, cleanroom service engineers, cleanroom designers and specifiers and anybody who is concerned with cleanrooms
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
- …
