scholarly journals Reviviendo el arte ancestral de elaborar acero persa al crisol para armas blancas

2012 ◽  
Vol 3 (2) ◽  
pp. 66
Author(s):  
Manouchehr Moshtagh Khorasani
Keyword(s):  
Font Size ◽  
Traditional Methods ◽  
Steel Making ◽  
Steel Bars ◽  
Crucible Steel

<p class="MsoNormal" style="text-align: justify; margin: 0cm 0cm 6pt;"><span style="mso-ansi-language: EN-GB;" lang="EN-GB"><span style="font-size: small;"><span style="font-family: Calibri;">This article is intended to both explain three traditional methods of manufacturing Persian crucible steel and to describe recent attempts by three German bladesmiths to replicate the results of traditional crucible steel making. The article will explain the process of making crucible steel, from the making of crucible steel cakes and forging of crucible cakes into bars, to polishing and etching these bars to reveal the crucible steel pattern. First described are three traditional methods of making crucible steel that are mentioned in Persian manuscripts. Second, elaborations are provided on three different modern processes carried out by three different talented German smiths, Achim Wirtz, Andreas Schweikert, and Cyrus Haghjoo. Finally, illustrations are shown some finished crucible steel blades made by Achim Wirtz and Andreas Schweikert as well as some crucible steel knives, made by the talented Belgian knifemaker Salsi Alessio, made from crucible steel bars provided by Achim Wirtz. </span></span></span></p>

The Many and Various Roles of Manganese in Iron and Steel Production

2020 ◽  
Vol 983 ◽  
pp. 57-63
Author(s):  
Paul T. Craddock
Keyword(s):  
Manganese Oxide ◽  
Manganese Oxides ◽  
Steel Production ◽  
Manganese Steel ◽  
Iron And Steel ◽  
Steel Making ◽  
Metallic Manganese ◽  
Crucible Steel ◽  
The Many ◽  
Iron And Steel Production

Manganese oxide and metallic manganese have made a long and varied contribution to the production of iron and steel through the centuries, long before Sir Robert Hadfield’s alloy manganese steel first produced in 1882. Although quite well known empirically, this contribution has sometimes been misunderstood or misrepresented.The success of some of the early so-called ‘natural steels’ was the presence of manganese oxides in the iron ores used.Manganese oxide was already used as a flux from the early days of the production of crucible steel in Asia and it now appears that it was used as a flux from the inception of the otherwise very different later European crucible steel technologies. After the introduction of crucible steel making in Britain in the 18th century, foreign competitors believed that the reason for the success of the processes used at Sheffield was a secret flux and studies on recently discovered 18th century crucibles in Sheffield have shown that process was indeed fluxed with manganese oxide.The function of manganese in the later European crucible steel industry has been rather overshadowed and confused historically by the very different ‘Carburet of manganese’, a strange concoction, patented by Josiah Heath in 1839 added to iron or steel to purify the metal. At the time the chemistry of the process was misunderstood and many acrimonious and inaccurate claims were made, crucially confusing the very different functions of manganese oxide and manganese metal, overshadowing the part already played by manganese oxide for almost a century previously..Finally manganese and its salts played a crucial role in the Bessemer process of steel making.

One Size Fits All?

Methodology ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Manuel C. Voelkle ◽  
Patrick E. McKnight
Keyword(s):  
Repeated Measures ◽  
Structural Equation ◽  
Type I Error ◽  
Equation Modeling ◽  
Type I ◽  
Finite Sample ◽  
Traditional Methods ◽  
Repeated Measures Anova ◽  
Special Cases ◽  
Latent Curve

The use of latent curve models (LCMs) has increased almost exponentially during the last decade. Oftentimes, researchers regard LCM as a “new” method to analyze change with little attention paid to the fact that the technique was originally introduced as an “alternative to standard repeated measures ANOVA and first-order auto-regressive methods” (Meredith & Tisak, 1990, p. 107). In the first part of the paper, this close relationship is reviewed, and it is demonstrated how “traditional” methods, such as the repeated measures ANOVA, and MANOVA, can be formulated as LCMs. Given that latent curve modeling is essentially a large-sample technique, compared to “traditional” finite-sample approaches, the second part of the paper addresses the question to what degree the more flexible LCMs can actually replace some of the older tests by means of a Monte-Carlo simulation. In addition, a structural equation modeling alternative to Mauchly’s (1940) test of sphericity is explored. Although “traditional” methods may be expressed as special cases of more general LCMs, we found the equivalence holds only asymptotically. For practical purposes, however, no approach always outperformed the other alternatives in terms of power and type I error, so the best method to be used depends on the situation. We provide detailed recommendations of when to use which method.

Steel Making at Ensley, Alabama

1904 ◽  
Vol 58 (1490supp) ◽  
pp. 23870-23870
Author(s):  
Day Allen Willey
Keyword(s):  
Steel Making

Analisis Kebutuhan Kamus Baca Bergambar untuk Mempermudah Siswa Belajar Bahasa Mandarin

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Chintya Prabawati ◽  
Anggraeni Anggraeni
Keyword(s):  
Learning Process ◽  
Qualitative Method ◽  
Swot Analysis ◽  
Font Size ◽  
Descriptive Qualitative

Kamus baca bergambar merupakan salah satu media penunjang pembelajaran yang dapat membuat siswa lebih tertarik dan mempermudah dalam proses pembelajaran. Berdasarkan observasi, bahwa banyak berbagai macam kamus baca bergambar yang ditemukan. Hal ini dapat mempengaruhi daya tangkap pemahaman siswa dalam Bahasa Mandarin. Oleh sebab itu, pada penelitian ini  peneliti berusaha menganalisis kamus baca bergambar Bahasa Mandarin sesuai dengan kebutuhan siswa. Tujuan penelitian ini, yaitu 1) Mengetahui kebutuhan siswa akan kamus baca bergambar untuk mempermudah siswa dan guru belajar bahasa Mandarin, 2) Mengetahui kesesuaian kamus baca bergambar dengan kebutuhan siswa melalui analisis SWOT untuk mempermudah belajar bahasa Mandarin. Penelitian ini menggunakan metode deskriptif kualitatif, karena peneliti akan menjabarkan kebutuhan kamus baca bergambar untuk mempermudah siswa belajar Bahasa Mandarin. Hasil dari penelitian ini menghendaki kamus baca bergambar yang sesuai dengan kebutuhan siswa berdasarkan penyusunan kosakata, jumlah kosakata per halaman, tampilan/ layout kosakata, font Hanzi, font size Hanzi, font Pinyin, font size Pinyin, gambar/ ilustrasi.Picture reading dictionary is one of the supporting learning media that can make students more interested and simplify the learning process. Based on observations, that many various kinds of picture reading dictionaries were found. This can affect the comprehension of students' comprehension in Mandarin. Therefore, in this study the researchers tried to analyze the Chinese picture reading dictionary according to the students' needs. The purpose of this study, namely 1) Knowing the needs of students for picture reading dictionaries to facilitate students and teachers learning Mandarin, 2) Knowing the suitability of picture reading dictionaries with students' needs through SWOT analysis to facilitate learning Chinese. This research uses descriptive qualitative method, because the researcher will describe the need for  a picture reading dictionary to facilitate students learning Mandarin. The results of  this study require a picture reading dictionary that suits students' needs based on vocabulary preparation, number of vocabularies per page, display / layout of vocabulary, Hanzi fonts, Hanzi font sizes, Pinyin fonts, Pinyin font sizes, pictures / illustrations.Picture reading dictionary is one of the supporting learning media that can make students more interested and simplify the learning process. Based on observations, that many various kinds of picture reading dictionaries were found. This can affect the comprehension of students' comprehension in Mandarin. Therefore, in this study the researchers tried to analyze the Chinese picture reading dictionary according to the students' needs. The purpose of this study, namely 1) Knowing the needs of students for picture reading dictionaries to facilitate students and teachers learning Mandarin, 2) Knowing the suitability of picture reading dictionaries with students' needs through SWOT analysis to facilitate learning Chinese. This research uses descriptive qualitative method, because the researcher will describe the need for  a picture reading dictionary to facilitate students learning Mandarin. The results of  this study require a picture reading dictionary that suits students' needs based on vocabulary preparation, number of vocabularies per page, display / layout of vocabulary, Hanzi fonts, Hanzi font sizes, Pinyin fonts, Pinyin font sizes, pictures / illustrations.

Cópulas en geoestadística o lo que se puede hacer con coordenadas y estructuras de dependencia

2013 ◽  
Vol 6 (2) ◽  
pp. 139
Author(s):  
Danna Lesley Cruz Reyes
Keyword(s):  
Title Page ◽  
Font Size

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span style="font-size: 10.000000pt; font-family: 'SFRM1000';">Es común en geoestadística utilizar métodos como el variograma o el coe- ficiente de correlación para describir la dependencia espacial y kriging para rea- lizar interpolación y predicción, pero estos métodos son sensibles a valores extremos y están fuertemente influen- ciados por la distribución marginal del campo aleatorio. Por lo tanto, pueden conducir a resultados poco fiables. Co- mo alternativa a los modelos tradicio- nales de geoestadística se considera el uso de las funciones cópula. La cópula es ampliamente usada en el campo de las finanzas y ciencias actuariales y debi- do a sus resultados satisfactorios empe- zaron a ser consideradas en otras áreas de aplicación de las ciencias estadísti- cas. En este artículo se muestra el efec- to de las cópulas como una herramienta que muestra un análisis geoestadístico bajo todo el rango de cuantiles y una es- tructura de dependencia completa, con- siderando modelos de tendencia espa- cial, distribuciones marginales continuas y discretas y funciones de covarianza. Se presentan tres métodos de interpolación espacial: el primero corresponde al indi- cador kriging y kriging disyuntivo, el se- gundo método se conoce como el kriging simple y el tercer método es una predic- ción plug-in y la generalización del kri- ging trans-Gaussiano, estos métodos son utilizados con base en la función cópula debido a la relación que existe entre las cópulas bivariadas y los indicadores de covarianzas. Se presenta resultados ob- tenidos para un conjunto de datos reales de la ciudad de Gomel que contiene me- diciones de isotopos radioactivos, conse- cuencia del accidente nuclear de Cher- nóbil. Finalmente, se presenta resultado obtenidos con el uso de cópulas discre- tas a un conjunto de datos simulados, esto permite realizar una extensión a los trabajos usuales de cópulas en Geoesta- dística. Este artículo es producto de la tesis de Maestría dirigida por el Profe- sor Edilberto Cepeda de la Universidad Nacional de Colombia. </span></p></div></div></div>

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