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PENGARUH PEMBINAAN GURU PENDIDIKAN AGAMA ISLAM TERHADAP PEMBENTUKAN AKHLAK MULIA PESERTA DIDIK KELAS IX SMP NEGERI 2 KAMANRE KECAMATAN KAMANRE KABUPATEN LUWU
Full text linkOptimasi Multi Respon Proses End Milling pada Material Paduan Aluminium 7075-T651 Berdinding Tipis Menggunakan Minimum Quantity Lubrication dengan Metode Backpropagation Neural Network-Genetic Algorithm
No full textKonstruksi struktur penerbangan modern, dibuat secara eksklusif sebagai struktur berdinding tipis berbahan paduan aluminium 7075, yang digunakan secara sempurna untuk meminimalkan berat konstruksi sebuah pesawat. Persyaratan ketat untuk konstruksi penerbangan modern adalah daya tahan dan keandalan yang tinggi. Elemen terpenting disini adalah massa struktur yang memiliki dampak menentukan pada penerbangan dan sifat teknis, serta efisiensi ekonomi. End milling merupakan salah satu jenis proses pemesinan face milling, yang digunakan untuk memproduksi material dengan bentuk-bentuk yang kompleks, seperti struktur berdinding tipis yang digunakan dalam konstruksi pesawat terbang. Nilai dari setiap parameter proses menjadi penting untuk ditentukan agar menghasilkan produk berdinding tipis yang berkualitas pada material paduan aluminium 7075-T651. Oleh karena itu, penelitian ini bertujuan untuk mengetahui parameter proses dan level-levelnya, yang dapat menimalkan kekasaran permukaan dan penyimpangan geometri pada proses end milling material berdinding tipis yang terbuat dari bahan paduan aluminium 7075-T651. Spesimen ini memiliki ukuran panjang 80 mm, lebar 16 mm, tinggi 36 mm, dengan dinding tipisnya memiliki ketebalan akhir 2 mm dan tinggi 25 mm. Eksperimen tersebut menggunakan matriks ortogonal L18 yang direplikasi dua kali. Parameter proses yang dimodifikasi adalah kecepatan spindle: 3000 rpm, 5000 rpm, 7000 rpm, kecepatan makan: 50 mm/menit, 100 mm/menit, 150 mm/menit, kedalaman pemotongan: 0,25 mm, 0,50 mm, 0,75 mm, dan arah penyemprotan cairan MQL: searah pemotongan dan berlawanan arah pemotongan. Metode backpropagation neural network (BPNN) digunakan untuk memodelkan hasil eksperimen. Arsitektur jaringan yang dihasilkan dari proses pemodelan BPNN digunakan sebagai fungsi objektiv dalam proses optimasi menggunakan Genetic Algorithm (GA). Selanjutnya, eksperimen konfirmasi dilakukan untuk memvalidasi dan mengkonfirmasi hasil dari proses optimasi yang telah dilakukan sebelumnya. Hasil optimasi multi respon menggunakan BPNN-GA menunjukan bahwa nilai minimum untuk respon kekasaran permukaan permukaan adalah 0,196 dan penyimpangan geometri adalah 0,205 dapat dicapai dengan menggunakan kecepatan spindle 7000 rpm, kecepatan makan 75 mm/menit, kedalaman pemotongan 0,25 mm dan arah penyemprotan cairan MQL searah pemotongan. Hasil eksperimen konfirmasi mampu menghasilkan nilai respon yang minimum sesuai dengan hasil optimasi. Penggunaan arah penyemprotan cairan MQL searah pemotongan dapat menghasilkan kekasaran permukaan dan penyimpangan geometri yang minimal. Kekasaran permukaan dan penyimpangan geometri mengalami peningkatan seiring dengan meningkatnya kecepatan makan dan kedalaman pemotongan, sedangkan kecepatan spindle yang maksimum dapat meminimalkan kekasaran permukaan dan penyimpangan geometri.
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The construction of modern aviation structure is made exclusively as thin-walled structure made from aluminum alloy 7075 which is used perfectly to minimize the construction weight of an airplane. The strict requirements for modern aviation construction are high durability and reliability. The important element here is structure mass that has a determining impact on aviation and technical properties, as well as economic efficiency. End milling is one of the types of face milling machining process which is used to produce materials with complex shapes, such as thin-walled structure used in aviation construction. The value of each process parameter has become essential to determine in order to produce quality thin-walled products from on aluminum alloy material 7075-T651. Therefore, this research aims to find out the process parameter and its levels that can minimize surface roughness and geometric deviation of end milling process of thin-walled materials made from aluminum alloy material 7075-T651. This specimen measures 80 mm long, 16 mm wide, 36 mm high with its thin wall having final thickness of 2 mm and height of 25 mm. The experiment used L18 ortogonal matrix replicated twice. The process parameter that was modified was spindle speed: 3000 rpm, 5000 rpm, 7000 rpm, feed rate: 50 mm/minute, 100 mm/minute, 150 mm/minute, depth of cut: 0,25 mm, 0,50 mm, 0,75 mm, and spraying direction of MQL liquid: in the direction of cutting and opposite the cutting direction. Backpropagation neural network (BPNN) method was used to model the result of the experiment. Network architecture resulted from the BPNN modelling process was used as objective function in the optimization process using Genetic Algorithm (GA). Furthermore, confirmation experiment was carried out to validate and confirm the result of optimization process that had been carried out previously. The result of multi response optimization using BPNN-GA showed that the minimum value for surface roughness is 0,196 and geometric deviation is 0,205 response could be achieved using spindle speed 7000 rpm, feed rate 75 mm/minute, depth of cut 0,25 mm and the spraying direction of MQL liquid was in the direction of cutting. The result of confirmation experiment was able to produce minimum response value in accordance with the optimization result. The use of the MQL liquid spraying direction that was in the direction of cutting could achieve minimum surface roughness and geometric deviation. Surface roughness and geometric deviation showed an increase as the feed and depth of cut increasing, meanwhile maximum spindle speed could minimize surface roughness and geometric deviation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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