1,720,993 research outputs found
Different approaches on skidding operation and wood transport investigation:integrate two different approaches in one model
No full textIn order to support an international cooperation in forestry operation, the Forest department of University of Ljubljana and the department of Land, Agriculture and Forestry of University of Padua are validating together a DSS model on forest operation in alpine condition. The project consists on first into verify partial models, independently developed, on valuating skidding operations and transportation of wood,. Models validation consists in exchanging independent approaches and consequently evaluates the results according to individual previous investigations. Once differences have been highlighted, a common DSS model will be developed and consequently apply in a common border productive forest area. The aim of the project is to aid a road map in forest operations in an area where wood raw material is becoming more and more attractive for both wood industry sectors. As a consequent it is becoming fundamental the optimization on wood allocation in terms of wood quality, assortments and supply cost
Estimating forest harvesting operations to achieve sustainable rural development in Samarina (Greece)
No full textMountainous areas, with altitude over 700 m, intense relief and slopes between 16-20%, cover 43% of Greece and they are usually characterized by low population density and long-term unemployment. The Greeks have a dependent connection among environment, economy and society as the history illustrates. Many of Greece's historic, cultural landscapes and native ecosystems have been degraded or isolated over the years. There is scientific evidence that Greece's natural/semi-natural forested areas cannot be sustained without watersheds, ridges and other natural corridors that connect its native landscapes and ecosystems. Logging systems are really ancient by using often only mules or horses. The aim of the work is to estimate how harvesting systems should be technologically upgraded improving forest work and social wellness maintaining at the same time ecological sustainability. Approach: The study area is held at Samarina region, a mountainous area of Northern Pindos in Greece. Social data were collected with questionnaires and local visits for better understanding of human resources for forest authorities and other administrative information's. DTM, Forest Inventory data and other GIS data have been derived by paper maps and previous studies. A registration of road-net and human resources within the protected area of Valia Kyrna and their contribution as factors for the sustainable development was used. The development of a Spatial Decision Support System that can concern all the conditions that are need in order to make an estimation of the optimal way of harvest a stand is really a challenge. Expected results: A GIS program is a powerful decision support tool in order to give the opportunity to the offices of Forestry to choose the optimal way of harvesting a stand and also to realize visually the effect's of such a kind of work; that is going to be held to the inhabitants and to the tourists of the area. Conclusion: The potential of social and ecological factors is examined as it concerns the promotion of the protected area within sustainable rural development. Advantages of registration in the form of aspatial tool, especially when many types of information participate, are presente
Evaluating costs on wood supply chain for supporting Slovenian and Italian forest cooperation
No full textThe purpose of the work was to analyse costs of the wood supply chain inside an area lying over borders between Italy and Slovenia. Two SDSS models, developed by University of Padova and by University of Ljubljana, were used to define cutting and skidding systems and their costs. The models consider different list of systems and different algorithms or parameters, but comparing results on the same area (Slovenia) forest utilization costs differ by only 0.8 €. After making cost averages and cumulating allowable cutting wood at road side, transportation costs were evaluated by networking analysis. Two scenarios (with and without boundaries between states) were studied and results show that wood could flow easily from Slovenia to Italy because of lower utilization costs, but also Italian wood could flow to Slovenia if it is far from terminals more than 30 km. Transportation costs are about 30% of total costs, so it would be possible to reduce total costs by introducing new technologies or raising cutting amount in forest compartments with productive function
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
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
Examination of transient behaviour and design of dynamic SPICE model of a-Si : H PIN structure
No full textKrc J, Stiebig H, Smole F, Topic M. Examination of transient behaviour and design of dynamic SPICE model of a-Si : H PIN structure. Journal of Non-Cryst. Solids. 2002;299-302:1295-1299.The dynamic properties of an a-Si:H PIN structure were investigated by measuring the admittance of the device applying small harmonic signals under different forward and reverse voltages. and under dark as well as illumination conditions. A dynamic electrical SPICE model of the PIN device, which covers all these operation regimes, was developed. The model parameters are discussed and their physical background is addressed. Additionally, an analysis of device dynamic behaviour by applying larger non-harmonic signals is presented. (C) 2002 Published by Elsevier Science B.V
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