1,720,963 research outputs found
ANALISIS CADANGAN, KUALITAS DAN DAMPAK PENAMBANGAN LEMPUNG SEBAGAI BAHAN BAKU GENTENG SOKA DAN BATA, DI KABUPATEN KEBUMEN
No full textPenelitian ini bertujuan untuk mengkaji tingkat kebutuhan, pemanfaatan, sebaran, kualitas, cadangan lempung dan dampak lingkungan disekitar sentra industri genteng di Kecamatan Sruweng dan Pejagoan Kabupaten Kebumen, yang mencakup kegiatan lapangan dan laboratorium. Penelitian lapangan meliputi penelitian sebaran bahan galian, aktivitas penambangan serta dampak lingkungan yang terjadi. Penelitian laboratorium mencakup analisis XRD menggunakan alat RINT2000 wide angle geniometer dan kimia mineral menggunakan metode AAS (Atomic Absorbtion Spectrometer). Lempung tersebar pada 13 lokasi seluas 1.320,870 Ha, dengan jumlah cadangan 19.544.143,00 m3. Berdasarkan analisis XRD, lempung mengandung kaolinit, monmorilonit, illit serta mineral induk. Kualitas lempung yang berasal dari Kebakalan setara dengan lempung dari Kedawung, lempung Kebagoran mempunyai kualitas lebih rendah dibandingkan lempung Kedawung, sementara itu lempung Plumbon kurang baik. Analisis kimia menunjukkan bahwa lempung dari Kebakalan dan Plumbon mengandung Fe2O3 sebesar 18,48 – 20,15 %. Indeks plastisitas berkisar antara 19,23 – 28,12% , susut kering sekitar 6%, susut bakar 9.5% sehingga memenuhi syarat untuk genteng keramik. Tingkat produksi genteng diperkirakan 174.424.333 bh/th, produksi batu bata 60.300.000 bh/th, maka diperlukan lempung 369.528,88 m3/th. Cadangan lempung yang ada diperkirakan dapat memenuhi kebutuhan selama 52,9 tahun. Nilai ekonomi cadangan lempung Rp 1,95 triliun, nilai potensial kerugian lahan akibat tidak panen Rp 84,78 milyar, nilai sewa sawah pada petani seharga Rp 63 juta/Ha, sehingga menguntungkan. Dampak lingkungan yang terjadi mencakup; hilangnya tanah penutup dan kesuburan tanah, perubahan topografi yang tidak sesuai karakter lahan serta rusaknya infra struktur. Untuk mengurangi perlu melokalisir area penambangan di sekitar Kebakalan-Logandu, melakukan reklamasi paska tambang dengan mengembalikan tanah pucuk, pemanfaatan lahan bekas tambang menjadi tempat perikanan/pemancingan, pembuatan zonasi kawasan tambang serta PERDA Pertambangan
MENGOPTIMALKAN PEROLEHAN MINERAL MAGNETIK PADA PROSES SEPARASI MAGNETIK PASIR BESI PANTAI SELATAN KABUPATEN KEBUMEN, JAWA TENGAH
No full textPotensi pasir besi Pantai Selatan Kebumen cukup tinggi. Material ini terdiri atas mineral magnetik dan bukan magnetik; yang pertama berupa magnetit lepas dan magnetit ikat yang berasosiasi dengan olivin, piroksin dan horblende, sedangkan yang kedua berupa kuarsa, K-feldspar, plagioklas, zirkon, rutil dan karbonat/fosil. Pemisahan optimum antara mineral magnetik dengan bukan magnetik dengan kadar Fe total maksimal memerlukan penelitian lapangan dan laboratorium. Penelitian lapangan dilakukan untuk pengambilan percontoh pada dua lokasi terpisah di bagian timur dan barat pantai Kebumen. Analisis laboratorium meliputi pengujian separasi magnetik pada fraksi kasar (-20 +35 mesh), sedang (-35+60 mesh) dan halus (-60+120 mesh) dengan intensitas magnetik 200 , 1000 dan 3000 Gauss. Mineral magnetik hasil separasi dianalisis kandungan Fe total, SiO2 dan TiO2 menggunakan metode AAS. Berdasarkan hasil analisis, mineral magnetik lebih banyak terdapat di bagian timur dengan prosentase sejumlah 66,46 % berat dan kadar Fe total 56,57 % yang didapat dari hasil separasi magnetik partikel berukuran -60+120 mesh dengan intensitas 200 G. Pemisahan mineral magnetik untuk percontoh berasal dari bagian barat menggunakan partikel berukuran -120+200 mesh dan intensitas magnetik 200 G. Hasilnya menunjukkan persentase mineral magnetik sebanyak 34,39 % berat dengan kadar Fe total 60,72 %. Kadar Fe total mineral magnetik berlawanan dengan SiO2 sedangkan TiO2 mengikuti pola Fe total
POTENSI BAHAN TAMBANG, PENATAAN WILAYAH USAHA PERTAMBANGAN (WUP) DAN WILAYAH PERTAMBANGAN RAKYAT (WPR) DI KEBUMEN
No full textPotensi kelompok mineral logam Kebumen terdiri atas pasir besi, mangan, dan emas; sedangkan kelompok batubaranya berupa serpih bitumen; kelompok bukan logam meliputi kaolin, Ca-bentonit, fosfat guano, tras, felspar, asbes dan talk. Kelompok batuan meliputi batugamping, tanah liat, andesit, diabas, gabro, basal, marmer, pasir-batu (sirtu) dan tanah merah. WUP mineral logam tersebar pada tiga lokasi yaitu kawasan Pantai Selatan (11.640 ha), tinggian Karangbolong (5.680 ha) dan Kebumen Utara (5.709 ha). WUP bukan logam tersebar pada dua lokasi, yaitu tinggian Karangbolong (1.875 ha) dan Kebumen Utara (7.488 ha). WUP batuan tersebar di kawasan tinggian Karangbolong (5.680 ha), Rowokele (5.587 ha), Karanganyar (7.598 ha) dan Kutowinangun Utara (14.980 ha). WPR dengan komoditas pasir sungai tersebar di S. Pedegolan, S. Kedungbener, S. Luk Ulo, S. Karanganyar, S. Kemit, S. Sampang dan Muara S. Cincingguling, serta WPR batubara pada tinggian Karangbolong
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
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