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Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
Magma/mantle interaction and genesis of primitive magnas
No full text上部マントルかんらん岩とメルトの相互反応をかんらん岩および噴出岩より読み取る研究を行い,以下の事実が明らかになった.1.高枯渇度かんらん岩には,水の存在下で生成されたもの(神居古潭帯)や,無水条件下で形成されたもの(パプア)がある.2.オマーン・オフィオライトのモホ遷移帯は基本的にはハルツバ-ジャイトと玄武岩質マグマとの反応の産物であり,太平洋ヘス・ディープのダナイト・トロクトライト・ガブロと類似している.3.海洋底玄武岩の形成モデルを提唱した.海洋底玄武岩は拡大速度によらずほぼ一定の化学組成を有することが知られている.一方,マントルかんらん岩は,拡大速度に依存したかなり大きな不均質性を有する.太平洋とケイマン・トラフのモホ遷移帯のダナイトの組成がほぼ類似していることから,初生マグマ(組成は拡大速度に依存して異なる)がかんらん岩とより低圧で反応することにより,はぼ同様のダナイトと二次的なマグマを生ずるらしい.4.かんらん岩とメルトの相亙反応による二次的メルトには,クロムなどのコンパティブル元素とナトリウム,水などのインコンパティブル成分が同時に濃集する.二次メルトからの晶出物の代表的なものはポディフォーム・クロミタイトである.5.クロミタイトは中程度に枯渇したハルツバ-ジャイトに特徴的に含まれる.また,そのスピネルのCr#は0.8前後のことが多く,海洋的というより島弧的環境を示唆する.6.ピクライト玄武岩はかんらん岩-メルト相互反応物の噴出相である.かんらん岩捕獲岩-アルカリ玄武岩の反応はピクライト的メルト(クリスタル・マッシュ)生成過程のよい類似物である.The interaction between upper mantle peridotite and melt has been studied both for deep-seated rocks and for effusive rocks. Our results are summarized as follows.
1. The highly depleted peridotite is possibly polygenetic. The Cr# of spinel in high-Mg harzburgite is higher in the Papuan ophiolite than in the Kamuikotan zone. the melting condition was hydrous in the Kamuikotan dunite-harzburgite and was anhydrous in the Papuan ophiolite.
2. The Moho transition zone of the Oman ophiolite is basically composed of the interaction product between harzburgite and MORB.The rocks are similar to the equivalents from Hess Deep, the Pacific Ocean, a fast-spreading ridge system.
3. The primitive MORB is possibly in equilibrium with dunite (and troctolite) of the Moho transition zone, an interaction product between more primitive MORB and mantle peridotite. The oceanic dunite is slightly variable in petrological characteristics whereas the mantle peridotite is highly variable depending on the spreading rate.
4. The secondary melt produced by the peridotite/melt interaction can concentrate both some compatible elements simultaneously and incompatible components, leading to precipitate podiform chromities.
5. The podiform chromitite is characteristically hosted by moderately depleted harzburgite with small smount of cpx and chromian spinel of moderate Cr# (around 0.5). Their chromian spinel often has high Cr#s (around 0.8), indicating supra-subduction zone environment for their formation.
6. The picrite basalt is an effusive facies of the peridotite/melt interaction product. The reaction product between peridotite xenolith and its host alkali basalt is a good analogue of the picritic mixture.研究課題/領域番号:07454131, 研究期間(年度):1995-1996出典：「マグマ-マントル相互反応と未分化マグマの形成」研究成果報告書 課題番号07454131
(KAKEN：科学研究費助成事業データベース（国立情報学研究所）)
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Origin of MORB deduced from the deep-seated rocks from the ocean floor
No full text1.MORBの生成と深部岩石の関係を探るために,太平洋ヘス・ディープと,カリブ海中央ケイマン・トラフから得られた超マフィック岩の再検討し,比較した.両者は,それぞれ高速拡大軸,低速拡大軸下の深部物質を代表している.両者のマントルかんらん岩はそれぞれハルツバーガイト(H),レールゾライト(L)であり大きく異なる.一方,ダナイト〜トロクトライト(D-T)はスピネルのCr#が0.5〜0.6,0.4〜0.5とわずかな違いしかない.この違いは,比較的未分化なMORBの組成が拡大速度にわずかに依存する事と調和的であり,これらは未分化MORBと化学的平衡にある.D-Tと未分化MORBは,既存のかんらん岩とメルトの相互反応の産物であろう.
2.それぞれ高速,低速拡大軸の海洋マントル起原であるオマーン・オフィオライトのマントル部分,およびリザードかんらん岩体を調べ,実際の海洋底の岩石との比較を試みた.オマーン・オフィオライトではヘス・ディープのものと類似するHが卓越する.ただし,大平洋では未発見のLがかなり普遍的に存在しており,レールゾライト〜ハルツバーガイトへの変化の詳細を知ることができる.リザードかんらん岩では,スピネルのCr#が0.1〜0.5のL〜Hが卓越し,Cr#0.3程度のスピネルを含む調和性ダナイトを伴う.
3.超低速拡大軸である南西インド洋海嶺(アトランティスII断裂帯)のかんらん岩を予察的に調べた.ほぼ同一斜面で深部から浅部へ向かってL〜Hの変化が認められた.Hにはしばしばダナイト的な部分があり,またガブロ質やパイロクシナイト質の脈〜層がしばしば認められる.この深さ方向の岩相変化はオマーンなどのオフィオライトでは認められており,海嶺軸下での溶融過程を制約するものとして重要である.今まで海洋底では未確認であり,岩相変化の幅と空間スケールの解析を引き続き行う予定である.1. Ultramafic rocks obtained from Hess Deep, EPR, and from Mid-Cayman Trough, the Caribbean, were petrologically examined to their difference, if any, depending on the spreading rate. The mantle peridotite is harzburgite (Hess Deep) or lherzolite (MCT), but the dunite-troctolite are only slightly different between the two. This difference is concordant with the primitive MORB compositional variation that is only slightly dependent on spreading rate. The dunite-troctolite are, thus, possibly in equilibrium with the primary MORB.Both the dunite-troctolite and MORB are the product of reaction between high-pressure MORB and peridotite at the uppermost mantle.
2. The mantle peridoitites in the Oman ophiolite, possibly formed at a fast-spreading ridge, and the Lizard peridotite, possibly formed at a slow-spreading ridge were compared with the ocean-floor peridotites. The mantle section of the Oman ophiolite is dominated by harzburgite similar to that from Hess Deep. Cpx-bearing harzburgite and lherzolite were found in deeper parts of the mantle section, and the melting process beneath a fast-spreading ridge can be discussed in detail. The Lizard peridotite is dominantly lherzolite to harzburgite with concordant dunite which has spinel with Cr# of 0.3.
3. The mantle peridotite from the Atlantis Bank, SWIR, was examined to know the melting process beneath a ultra-slow spreading ridge. An upward lithological variation from lherzolite to harzburgite on a slope of the Atlantis II FZ was confirmed, which can give us constraints on the space and temperature legime of mantle melting beneath the ridge.研究課題/領域番号:10440152, 研究期間(年度):1998-2000出典：「海洋底深部岩石からみたMORBの成因」研究成果報告書 課題番号10440152
（KAKEN：科学研究費助成事業データベース（国立情報学研究所））
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Formation and modification of the mantle wedge: from the ocean to the confinent
No full text今年度は特にアダカイトの関与によって形成されたと思われる捕獲岩の研究が進展した.スペイン,タジャンテおよび唐津高島で得られた,かんらん石と反応して生成された斜方輝石に富む捕獲岩(あるいは脈)を詳細に検討した.単斜輝石の微量元素組成やREEパターンはアダク島(アリューシャン)のアダカイト中の斑晶のそれちとほぼ一致することが判明した.従って,これらの単斜輝石はアダカイト的なメルトと平衡であり,関与したメルトの性質が判明した.これらの斜方輝石に富むパイロクシナイトはアダカイトやマントル・ウェッジ中の通路を表していると思われる.アダカイトの化学組成変化はかんらん石の消費+斜方輝石の晶出により基本的にコントロールされていることが明かとなった.また,タジャンテのかんらん岩中のフェルシック脈の周囲に形成されているオルソパイロクシナイが明かとなった.また,タジャンテのかんらん岩中のフェルシック脈の周囲に形成されているオルソパイロクシナイト中にはNbに富むルチルが存在しており,全体としてLILEに比べてHFSEに富むことが判明した.これにより,上記の反応はスラブメルトにHFSEの負の異常を与える可能性があることが判明した.このような斜方輝石に富む岩石は,産状や輝石の組成からフルイドとかんらん岩の反応によって生成されたと考えられる斜方輝石(カムチャツカ弧,アバチャ火山のものなど)と区別される.アセトル・ウェッジはスラブメルトやスラブ起源のフルイドによりシリカに富むことが明確となった.また,スラブとマントル・ウェッジの反応のアナログとして注目される三郡変成岩中の落合-北房かんらん岩の全岩の微量元素組成を検討した結果,RbやCsなどが変成岩からかんらん岩に付加していることがわかった.またこれらの元素はNaトレモライトに含まれることがわかった.Orthopyroxene-rich xenoliths from Tallante, Spain, and Takashima, SW Japan, have been investigated. They were farmed by a reaction between the slab melt(adakite melt) and the mantle peridotite. Their dinopyroxene is similar in trace-element characteristics and REE pattern to clinopyroxene phenocrystin adakite from Adak Island of the Aeutian arc. This may indicate that an adakitic melt was involved information of the opx-rich pyroxenite xenoliths from Tallante and Takashima. They possibly derived from the conduit of adakitic melt within the mantle wedge. The chemical compositional trend of adakite is, therefore, basically controlled by precipitation of orthopyroxene at the expense of olivine. The orthopyroxenite from Tallante contains some HFSE-rich minerals such as Nb-rich rutile, and is enriched with HFSE relative to LILE. This means that the reaction above can yield negative spikes of HFSE to the fractionating slab-derived melt. The orthopyroxene in such pyroxenites, interpereted here to be a slab-melt/peridotite reaction product, is distinctively different from the oryhopyroxene that is interpreted to be fluid/peridotite reaction product, described from Avahc and Iraya volcanoes. We have stated a geochemical analysis of metamorphosed/metasomatized peridotite of the Ochiai-Hokubo comprex, emplaced into the Sangun highP/low T schist, as an analogue to mantle-wedge peridotite interacting with slab. The peridotite is clearly enriched with Rb and Cs in addition to H2O, and these dements are concentrated in metasomatically formed Na-trermolite.研究課題/領域番号:13440161, 研究期間(年度):2001-2003research repor
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
An integrated genefical model and exploration/evaluation system for chromittite and platinum-group element ores
No full textクロマイトの成因に関しては,オマーンオフィオライトの地殻部のポディフォームクロミタイトの研究により,飛躍的な発展をとげたと考える.このクロミタイトは後期貫入岩とそれに取り込まれたガブロの部分溶融メルト(シリカに富む)の境界付近にレンズ状に生じており,産状的にはポディフォームである.一方,スピネルは細粒で完全な自形であり,マトリックスには斜長石が卓越する.スピネルはクロム,鉄に富んでいる.これらの特徴は層状貫入岩体の層状クロミタイトのものと一致する.すなわち,このクロミタイトは今まで記載されたことのない,オフィオライトで層序的に最上位のポディフォームクロミタイトであり,層状クロミタイトの特徴も合わせ持つ,両者の中間的なものである.この層状クロミタイトに組成の類似したクロミタイトは,後期貫入岩を作った玄武岩質マクマとガブロの部分溶融メルトの混合により形成されたと解釈できる.従って,層状クロミタイトはIrvine(1975)が最初に主張したように,玄武岩質マグマとマグマ溜りの周囲の地殻岩が部分溶融したシリシックメルトの混合でできたものであろう.Arai and Yurimoto(1994)のかんらん岩中のポディフォームクロミタイトの成因論を合わせ考えると,クロミタイトの生成にはそのタイプを問わず,2種類のマグマの混合が不可欠であることがわかる.一方はかんらん石-スピネルに飽和した玄武岩質のものであり,他方はシリカに富むメルト(通常のポディフォームクロミタイトではマントル斜方輝石の分解溶融によるもの,層状クロミタイトでは地殻の岩石の部分溶融メルト)である.また,マントルのポディフォームクロミタイトの生成は,斜方輝石か非調和融解するような最上部マントルの方がより効果的に行われると思われる.白金族元素鉱物の生成にも2種類のマグマの混合は有利てある.玄武岩マグマが白金族元素を,シリカに富むメルトは硫黄を供給する.An integrated model for chromitite genesis has been established through the petrological research of upper crustal podifarm chromitite that we found from the Oman ophiolite. Ihis chromitite is lenficular and was formed at the boundary between the late-intrusive peridotite and felsic partial meltfrom gabbroic blocks captured by the late intrusion. Despite the podiform character, its spinel is perfectly euhedral and fine and has a matrix of plagioclase. Spinel is rich in Cr and total Fe. These features are similar to those of the stratiform chromitite. In short, this chromitite has an intermediate character between the podiform and stratiform chromitites. It was formed by mixing of two kinds of magma, a basaltic one from the late intrusive body and a felsic one from the partial melt of gabbro. The chemical similarity between the upper crustal chromitite from Oman and the stratifrom chromitite may mean that the latter is also formed by mixing of magmas, a basaltic magma and a silicic one formed by partial melting of wall of the magma reservoir as first suggested by Irvine(1975). Combined with an interpretation of Arai and Yurimoto(1994) on the origin of podiform chromitite in peridotite, the mixing of two kinds of magma, basaltic and silicic ones, is indispensable to genesis of chromitite irrespective of type. This mechanism favors the precipitation of primary PGM by supplies of PGE from basalt and of S from a silicic melt.研究課題/領域番号:13554017, 研究期間(年度):2001-2003出典：「クロムおよび白金族元素鉱床の統一的成因論および探査/評価システムの確立」研究成果報告書 課題番号13554017
(KAKEN：科学研究費助成事業データベース（国立情報学研究所）)
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