Abstract. Radial growth of the trees and its relationships with other factors is one of the most important research areas of forestry for a long time. For measuring intra-annual growth there are several widely used methods: one of them is measuring the girth of trees regularly, preferably on weekly basis. However, the weekly measured growth data may have bias due to the actual precipitation, temperature or other environmental conditions. This bias can be reduced and using adequate growth functions the discrete growth data can be transformed into a continuous curve.In our investigations the widely used logistic, Gompertz and Richards sigmoid growth models were compared on intra-annual girth data of beech trees. To choose the best model two statistical criteria, the Akaike weight and the modified coefficient of determination were examined. Based on these investigations and the view of applicability, Gompertz model was chosen for later applications. However, we came to the conclusion that all three models can be applied to the annual growth curve with sufficient accuracy.The modified form of the Gompertz function gives three basic curve parameters that can be used in further investigations. These are the time lag, the maximum specific growth rate and the upper asymptotic value of the curve. Based on the fitted growth curves several other completely objective curve parameters can be defined. For example, the intersection of the tangent drawn in the inflection point and the upper asymptote, the distance between upper intersection point and the time lag, the time and value of the inflection point etc. and even different ratios of these parameters can be identified. The main advantages of these parameters are that they can be created uniformly and objectively from the fitted growth curves. This paper demonstrates the application opportunities of the curve parameters in a particular study of tree growth.
A fák növekedése és az azt befolyásoló id?járási tényez?k kapcsolatának vizsgálata id?sorok elemzését igényli. A cikk az európai erdészeti publikációk alapján bemutatja az adatokat csoportosító, elemz?, és az elemzések stabilitását javító módszereket. A tapasztalatok alapján a komplexebb összefüggések feltárásához a primer változókból szisztematikusan szekunder adatsorokat kell képezni és azokat elemezni, amely egy egységes elemz? folyamat kifejlesztését követeli meg. A szisztematikus transzformációs elemz? módszer (STAM) struktúrája három komponenst foglal magában. Az els? modul az eredeti adatokból input adatokat származtat anélkül, hogy azok tartalmát megváltoztatná. A STAM magja a transzformációs egység, ami egy ablakos technikával képzi a szekunder adatokat. A harmadik komponens az elemzésért felel, amely a publikációkban látott, illetve a szoftver eszközökben rendelkezésre álló módszereket képes alkalmazni. A STAM általános struktúrája lehet?vé teszi a módszer más szakterületeken való alkalmazását is.
The provision of services with complex multi-layer communication networks requires appropriate and generic network models describing accurately the existing networks and flexible softwares supporting the adaptation of the used algorithms to the new planning and analysis tasks. The paper introduces an object-oriented modeling and planning tool that is suitable to describe the existing multi-layer networks in detail, provides framework for modeling, dimensioning and analyzing new technological solutions, and for introducing new planning and evaluation approaches and algorithms. The framework is used at Hungarian Telekom, and its capabilities are validated with some illustrative examples. I. MOTIVATION AND PRELIMINARIESThe evolution of information services requires the continuous enhancement and development of the telecommunication infrastructure. This development is not a simple qualitative change, but in the last two decades several new communication technologies become available and many others were investigated as possible options. Both the available and the possible future technologies offer increasing capacities, however, instead of replacing each other step by step the different technologies compose complex multi-layer architecture and provide higher level and new networking and end-user services.This always changing and evolving environment requires complex networking models that support not only the management of the different networking layers, but the administration, design and analysis of these multi-layer networks taking into consideration the resilience schemes provided by the different layers. Therefore, the provision of high-value services with complex multi-layer communication networks requires not only appropriate and generic network planning and analysis models that accurately describe the existing network structure and components, but the design and analysis software environment should be flexible to support the adaptation of the used algorithms to the new dimensioning and evaluation challenges.The academic research group provides planning and analysis models and tools for the Hungarian Telekom for more than 20 years ([1], [2]).taking information from the management systems. The role of this operational database is presented in details in [3].This paper focusses on the flexible network model and tool, and it is organized as follows:• in Section II the relating works are briefly summarized, • in Section III the structure of the design and analysis tool is introduced, • Section IV presents the concept of the flexible network model and some details concerning its main components, • Section V illustrates the application of the model, and finally • in Section VI the paper is concluded and the planned further activities are highlighted. II. NETWORK MODELING APPROACHESThe network designing models can be classified according to several aspects. In the next subsections two of the interesting viewpoints will be emphasized: the generic models for different technologies provided by the telecommunication indu...
The defoliation and crown dieback data of trees are typical indicators of forest health condition. In Hungary the data are collected in the frame of the national forest monitoring program and based on Forest Protection Network from 1987. In the paper these two data lines are investigated: (i) trend analysis was performed in respect of the examined time period according to different criteria, (ii) the relationships between healthy features and basic and derived climatic variables were examined by correlation analysis. The paper gives a general overview of the Hungarian forest health condition. Detectable general trends and statistically significant relationships are defined for all examined species and for 12 groups (subsets) of species. The received general results help us to determine further directions of deeper and more detailed investigations.
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