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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
(18(3):39-47)EFFECT OF C : N RATIO OF ORGANIC MATTER ON AGGREGATION OF SOILS
No full text為究明不同C/N比之有機物施用對土壤團粒化之效能，將以硫銨調節之不同C/N比（80,40及20）之新鮮稻草粉及腐熟度不同之堆肥（C/N比為44.4及21.6）以500mg碳/100g土壤之比例，分別加入於砂頁岩酸性沖積土與粘板岩鹼性沖積土，然後將各處理土壤分別分為二組，各放置於10℃與25℃之不同溫度之恒溫箱內70天，以適當水分狀態下，使有機物分解。在放置期間，每十四天，取出一部份土壤，分析各處理土壤之碳、氮含量之變化及大於0.05mm團粒之安定度，玆將主要結果列舉於如下：
1.低C/N比稻草施用土壤之有機碳損失量較高於高C/N比稻草施用者之損失量，但高C/N比之新鮮堆肥施用土壤之碳損失量，即較高於低C/N比之腐朽堆肥施用者之損失量。新鮮稻草施用土壤之碳損失量，均高於同C/N比堆肥施用土壤之損失量。高溫處理土壤之碳損失量，均高於同C/N比之低溫處理土壤之損失量。
2.高C/N比之稻草施用土壤之氮損失量，均高於低C/N比之稻草施用土壤之損失量，但堆肥施用土壤之氮損失量，無論其C/N比之高低，其損失量均頗相近，而其損失量較同C/N比稻草施用土壤之損失量為少。不同溫度之處理對各處理土壤之氮損失量亦無顯著影響。
3.不同C/N比有機物施用之土壤團粒化之效能，無論稻草粉或堆肥之別，均以高C/N比之有機物之效能較高於低C/N比之有機物，而新鮮稻草之效能，均較高於同C/N比堆肥之效能，但堆肥之效果比稻草效果者，維持較長。高溫處理，即促進有機物之分解速度，均能增加有機物之土壤團粒化效能。
誌謝：本研究承國家科學委員會之資助，方能完成謹致謝忱。
Fresh rice straw varied in C:N ratios which adjusted with ammoniurn sulphate to 80, 40 and 20 and rice straw compost with different C:N ratios of 44.4 and 21.6 are applied to acid, sand stones and shales alluvial soil and alkaline, slate alluvial soil at the rate of 500mg carbon per 100g soil.
The changes in contents of carbon and nitrogen in the treated soils and the aggregate stabilities of the soils are determined every 14 days during the incubation at 25°C and 10°C for 70 days respectively.
The results are summerized as follows:
1. The organic carbon loss of the soils applied with rice straw of lower C:N ratio is found more than that of the soils applied with that of higher C:N ratio but the reverse effect is found in soils applied with compost. Higher incubation temperature has increased the loss of organic carbon in the all treated soils.
2. The nitrogen loss of soils applied with rice straw of higher C:N ratio is found more than that of soils applied with that of lower C:N ratio, but about the same amounts of the loss are found in all soils applied with compost regardless of difference in C:N ratio.
3. The higher C:N ratio of the straw or compost applied, the higher aggregate stabilities of the treated soils are found and higher incubation temperature tends to increase the efficiency of organic matter applied
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
(14(4):33-43)臺灣坡地主要土壤之沖蝕性研究 I.影響土壞沖蝕之性質
No full textTo evaluate their relative erodibility, six soils from cultivated lands on the slopes ranging from 15% to 25% were subjected to the field study on their soil profile characteristics and infiltration capacity. Analyses on their physical and chemical properties including porosity, particle size distribution, dispersion ratio, aggregate stability, clay ratio and contents of organic matter and free iron in the soils were carried out.
The results revealed that:
1) Highly porous profile of the soil resulted in higher infiltration capacity of the soil. The infiltration rates of all soils were decreased rapidly in first 30 minutes and then gradually decreased to the stable minimum values in 100 minutes. Higher infiltration rates were found for Tsao-tun (草屯) soil and Feng-san (鳳山) soil, but lower rates for Ah-kung-tien (阿公店) and Yen-chao (燕巢) soils.
2) All of the soils tested are highly dispersible according to their dispersion ratios and aggregate stabilities. Lower dispersion ratios were found for Tsao-tun (草屯), Tai-tung (臺東) and Pin-chen (平鎮) soils and higher ratios for Feng-san (鳳山) , Yen-chao (燕巢) and Ah-kung-tien (阿公店) soils.
3) According to the result of higher dispersion ratios of subsoils, it is expected that soils will he easily eroded once the subsoils are exposed and cultivated.
4) The resistance to dispersion of the soils were increased directly with the contents of organic matter and clay in the soils and no evident relationships were found for free iron content.
5) Based on the infiltration rate and dispersion ratio of the soils, Tsao-tun (草屯) soil is regarded as the least erosive and soils of Ah-kung-tien (阿公店) and Yen-chao (燕巢) as easily erosive.
為探究丘陵地區坡地主要土壤之相對沖蝕性，選擇坡度在 15~ 25%土壤深度 70 公分以上之耕地土壤，在現地作部面性狀觀察與水分滲浸率側定，並就土層別採取土壤在室內測定與土壤沖蝕有關之各種土壤理化性質。
本試驗選擇的土壤共有六種即（l）平鎮洪積臺地上紅壤（2）草屯砂頁岩風化黃壤（3）燕巢砂岩風化黃壤（4）阿公店泥岩風化石質土（5）鳳山洪積層紅壤與（6）臺東頁岩風化石質土。
室內分析項目有（l）機械分析（2）孔隙度（3）分散率（4）團粒安定度（5）土壤反應（6）有機質含量與（7）粘土率。
其結果簡述如下：
1. 土壤剖面之孔隙度較高的土壤 (如草屯土壤），其現地水分滲浸率較高，所有土壤之滲浸率在最初 30 分內均急速減低，以後即緩慢減低，至 100 分時達到安定的最低滲浸率。其最低滲浸率以草屯、鳳山，土壤較高，阿公店及燕巢土壤較低，其差異多至 5 倍左右。
2. 土壤分散率與團粒安定度之側定結果顯示，所有土壤均頗易分散其分散率大多在 20 以上。草屯、臺東及平鎮等土壤之分散率較低（20~30）而鳳山、燕巢及阿公店等土壤之分散率均高 (30~50)。
3. 所有土壤之底土分散率均高於表土，由此可推測現有表土流失底土露出而被開墾呈膨鬆狀態時更易引起沖蝕。
4. 土壤之有機物及粘土含量對土壤分散率及團粒安定度有直接關係。有機物與粘土含量愈高，分散率愈低，而團粒安定度即愈高。但游離鐵含量則未發見有相關關係。
5. 由土壤分散率與水分滲浸率測定之綜合結果，因其分散率低（18~27）滲浸率高(30公糎/10分)，草屯土壤被認為最難被沖蝕。阿公店及燕巢土壤因分散率高（30~50）滲浸率低（6~9公糎/10分）被認為最易被沖蝕之土壤
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
(16(4):15-26)THE EFFECTS OF SOME AGGREGATE STABILIZERS ON ERODIBILITY OF THE SOILS
No full text為探究Polyvinyl alcohol（PVA），有機物（魯冰粉）與石灰（CaCO3）之施用，對土壤沖蝕性之影響，將不同質地之坡地土壤，即砂質壤土，壤土及粘土各加不同量之PVA（0.1%，0.2％及0.4%），風乾魯冰粉（0.2%，0.4％及0.6%）及純碳酸鈣（石灰需要量之1/3，1/2及全量），測各處理土壤之分散率，團粒安定度及水分滲透率，其結果為：
(l) 對土壤分散率之影響：PVA及有機物之加用，均有減低土壤分散率之效果，其效果隨施用量之增加而有增加的現象，尤以施用於砂質壤土效果最顯著。PVA之效果遠大於有機物，石灰施用即無顯著影響。
(2) 對土壤團粒安定度之影響：PVA，有機物及石灰對各種土壤均有提高安定度之效果，惟有機物及石灰之效果相差無幾，但遠不及PVA之效果。PVA之效果，在砂質壤土最顯著。
(3) 對水分傳導度之影響：PVA之施用隨其施用量之增加而增加各種土壤之水分傳導度，並且其效果頗顯著。有機物施用之效果因質地之不同而有異，對粘土與壤土其增加效果隨施用量之增加而增加，尤以對粘土之效果最顯著。對砂質壤土，有機物之施用均減低水分之傳導度。石灰施用，其施用量在石灰需要量之範圍內，稍有增加傳導度，其效果在粘土，施用量達到石灰需要量時最顯著，對砂質壤土即幾乎無影響。
由上述結果可推側PVA之施用對增加土壤之抗蝕力而言，最有效果，有機物次之，而石灰即無影響。
Upland soils of different textures, sandy loam, loam and clay, were treated with different amounts of polyvinyl alcohol (PVA: 0.1%, 0.2% and 0.4%), organic matter (air dried lupine powder: 0.2%, 0.4% and 0.6%) and lime (pure CaCO3: 1/3, 1/2 and total of lime requirements of the soils). The results of laboratory study on their effects on dispersion ratio, aggregate stability and initial hydraulic con-ductivity of the soils indicated that:
(1) Dispersion ratios of the soils were greatly decreased by the applications of PVA and organic matter, although the effect of PVA was by far more efficient than that of organic matter. The greater effects of the both were found in sandy loam soils. The application of CaCO3 did not affect dispersion ratios of the soils appreciably.
(2) Aggregate stabilities of the soils were increased by the applications of PVA, organic matter and lime, and the effects were increased with increase of the amounts applied. The effect of organic matter was almost equal to that of lime, whereas the effect of PVA was highest. The effect of PVA was found much effective in sandy loam soils.
(3) The initial hydraulic conductivities of the soils were increased dramatically by the application of PVA and the effect was increased with increase of the amounts applied. The effects of organic matter and CaCO3 were varied depending on the textures of the soils. The initial conductivities of clay soils were greatly increased by the application of organic matter, whereas those of loam soils were slightly increased. The initial conductivities of sandy loam soils were decreased by the applications of organic matter with any amount. The application of CaCO3, less than the amount of lime requirements of the soils, increased the initial hydraulic conductivities of clay and loam soils slightly, although CaCO3 application of total amount of lime requirement increased those of clay soils greatly. The conductivities of sandy loam soils were little affected by CaCO3 application.
As a conclusion based on the results above, PVA is regarded as the most effective in increasing soil’s resistance to erosion, organic matter is less and CaCO3 is not effective
(19(1):40-45)STUDIES ON THE AMELIORATION OF CASING SOILS IN MUSHROOM CULTURE
No full text（1）根據實驗分析結果得知土壤之孔隙量及容水量由團粒之大小不同而有差異即粒徑愈小其容水量愈大，在孔隙量粒徑愈大亦隨之大，各種不同材料中蔗渣的孔隙量與容水量均較高於穀殼粉及泥炭。
（2）土壤團粒之大小對洋菇產量以土壤粒徑1.0mm~0.5mm較優，泥炭對洋菇產量，土壤混合率25％處理區最高，若泥炭的用量過多時雖不致減少，也無法提高洋菇產量，穀殼粉土壤分層使用可能保持良好的孔隙量故其產量較優於土壤混合使用區，蔗渣本身之容水量孔隙量雖然高於其他材料區，但不見到較好的效應。
（3）本次試驗僅探討土壤團粒度，及泥炭，穀殼粉，蔗渣等與土壤混合做覆蓋土時之孔隙量，容水量之差異情形及洋菇生產之影響，獲得初步結果，卻尋求理想的覆蓋土，土壤應有之處理或產量之影響尚待今後繼續研究。
The porosity and water holding capacity as well as the effect on mushroom yield of various casing soils which differ either in the size of granule or in the material incorporated (i. e., peat power. husk powder and bagasse power) were tested in this experiment. The primary results obtained were as follows:
(1) The optimum size of granule for casing soil was observed about 1.0 mm~0.5 mm.
(2) Among the casing soils in which different proportions of peat powder were incorporated that with 25 per cent peat was found most adequate for yield.
(3) Although the bagasse powder showed both biggest porosity and water holding capacity among all the materials tested, no superior effect of the incorporation in casing soil was observed
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
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