scholarly journals Registration of rock blocks movements using dendrogeomorphic methods: new methodical approach in a case of localities in the Moravskoslezské Beskydy Mts.

Geografie ◽  
2014 ◽  
Vol 119 (1) ◽  
pp. 50-66 ◽  
Author(s):  
Karel Šilhán ◽  
Tomáš Pánek
Keyword(s):  
Tree Ring ◽  
Lateral Spreading ◽  
Growth Suppression ◽  
Growth Disturbances ◽  
Resin Ducts ◽  
Systematic Procedure ◽  
Methodical Approach ◽  
Traumatic Resin Ducts ◽  
Heavy Rainfalls

This study proposes a new systematic procedure for the dendrochronologic dating of the movement (esp. lateral spreading, backward rotation and toppling) of large boulders with precision to seasons. The methodology is based on the dendrogeomorphic analysis of trees which have been deformed by tilting blocks. Based on the research carried out in four localities within the Moravskoslezské Beskydy Mts, we have identified 22 event years revealing deformations caused by blocks. The interaction between tree stems and tilting blocks is represented by various macroscopic changes as well as growth disturbances within tree-ring series. These most frequently involve tangential rows of traumatic resin ducts and abrupt growth suppression/release. An analysis of meteorological characteristics identifies potential triggers of movements featuring especially summer heavy rainfalls.

Aspects of robot repeatability

Robotica ◽  
1987 ◽  
Vol 5 (3) ◽  
pp. 223-230 ◽  
Author(s):  
B. W. Mooring ◽  
T. J. Pack
Keyword(s):  
Data Acquisition ◽  
Robot Manipulator ◽  
Test Procedure ◽  
Good Deal ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Systematic Procedure ◽  
Standard Procedures ◽  
Methodical Approach ◽  
Repeatability Test

SUMMARYOne of the most important specifications associated with a robot manipulator is repeatability. Unfortunately, there are no standard procedures for determining or specifying the repeatability of a robot. This situation has resulted in a good deal of confusion when attempting to use a published repeatability specification to determine if a robot will meet the requirements of an application.The purpose of this paper, therefore, is to propose a systematic procedure for the determination and specification of robot repeatability. To accomplish this, three aspects of repeatability analysis are examined. First, a method of collecting data to study repeatability is discussed. A data acquisition system is described as well as an associated test procedure. Next, a procedure for utilizing the acquired data to develop a repeatability specification for a robot is proposed. This procedure results in a specification of the robot's ability to orient objects as well as the classical specification for positioning repeatability. A methodical approach to determining where in the workspace the repeatability test should be made is also addressed. Finally, an approach is presented whereby the data collected during the repeatability test may be used to determine which joints contribute most to the variations in robot repeatability.

Effects of Weevil Feeding on Resin Duct Density and Radial Increment in Lodgepole Pine

1972 ◽  
Vol 2 (1) ◽  
pp. 11-15 ◽  
Author(s):  
H. F. Cerezke
Keyword(s):  
Radial Growth ◽  
Lodgepole Pine ◽  
Radial Increment ◽  
Resin Ducts ◽  
Resin Duct ◽  
Traumatic Resin Ducts

Wood discs cut from 23-year-old lodgepole pine (Pinuscontorta Dougl. var. lalifolia Engelm.) stems were analyzed for vertical and radial resin duct densities adjacent to basal injuries caused by the weevil, Hylobiuswarreni Wood. The injury from single attacks continued for at least 2 years and was characterized by reduced radial growth and an abundance of vertical 'traumatic' resin ducts above the wounds. No increase in radial duct density was detected above the wounds.

Increment Coring Induced Traumatic Resin Ducts in White Spruce But Not in Lodgepole Pine

2020 ◽  
Vol 76 (1) ◽  
pp. 54 ◽  
Author(s):  
Jennifer G. Klutsch ◽  
Chen X. Kee ◽  
Eduardo P. Cappa ◽  
Blaise Ratcliffe ◽  
Barb R. Thomas ◽  
...  
Keyword(s):  
Lodgepole Pine ◽  
White Spruce ◽  
Resin Ducts ◽  
Traumatic Resin Ducts

scholarly journals Traumatic resin ducts in Larix decidua stems impacted by debris flows

2008 ◽  
Vol 28 (2) ◽  
pp. 255-263 ◽  
Author(s):  
M. Bollschweiler ◽  
M. Stoffel ◽  
D. M. Schneuwly ◽  
K. Bourqui
Keyword(s):  
Debris Flows ◽  
Larix Decidua ◽  
Resin Ducts ◽  
Traumatic Resin Ducts

Tree-ring dating of snow avalanche history in Parâng Mountains (Southern Carpathians, Romania)

2020 ◽  
Author(s):  
Corina Todea ◽  
Olimpiu Pop
Keyword(s):  
Tree Ring ◽  
Snow Avalanche ◽  
Mountainous Area ◽  
Snow Avalanches ◽  
The Past ◽  
Avalanche Hazard ◽  
Hiking Trails ◽  
Traumatic Resin Ducts ◽  
Tree Ring Data ◽  
Southern Carpathians

<p>In high mountainous areas worldwide, snow avalanches represent one of the main morphodynamic processes which influence the morphology of steep slopes. They usually disturb the forests, and represent a significant natural hazard that may endanger the safety of tourists exposed along the hiking trails crossing the avalanche-prone slopes. In the context of the growing tourism activities in the area where tourist become exposed to snow avalanche hazard, there is need for detailed analysis for documenting the past activity of this geomorphic process, especially in remote areas where historical data is lacking. Such mountainous area without snow avalanche monitoring and archival records is in Parâng Mountains (Southern Carpathians, Romania). On forested slopes, trees disturbed by snow-avalanches may record in their growth rings information about the past event occurrence. The main aim of this study is to improve the knowledge about the past snow avalanche history using tree-rings approach. To this end, 57 disturbed spruce (Picea abies (L.) Karst.) trees growing along an avalanche path located on the western slopes of the Parâng Mountains were sampled and their growth disturbances (scars, traumatic resin ducts, compression wood and growth suppression sequences) served to reconstruct the snow-avalanche history back to 1950. Tree-ring analyses allowed reconstructing a minimum of 14 snow avalanche events which occurred in the past along the investigated path. The tree-ring approach presented in this study proved to be a valuable tool in reconstructing snow avalanche history and compliting the snow avalanche database in Parâng Mountains. The number and spatial extent of documented snow avalanches evidence the potential snow avalanche hazards in the study area. The tree-ring data from the present study, together with those presented by the previous studies in the study area may further contribute to the snow avalanche hazard assessment. </p>

scholarly journals Dendrogeomorphology of Different Landslide Types: A Review

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 261
Author(s):  
Karel Šilhán
Keyword(s):  
Tree Ring ◽  
Specific Growth ◽  
Signal Extraction ◽  
Climate Variations ◽  
High Importance ◽  
Growth Disturbances ◽  
Landslide Activity ◽  
Absolute Dating ◽  
Ring Analysis ◽  
Geomorphic Processes

The dating of past landslide events is one of the most crucial aspects of landslide research, leading to a better understanding of past landslide activity. Landslides can be extremely dangerous natural hazards, and thus, solving the relationships between their activity and climate variations is of high importance. For these purposes, data about past landslide activity are fundamental for such analyses. Various methods of landslide absolute dating exist, but the most precise approach that dates back several centuries is based on tree-ring analysis (dendrogeomorphology). Landslide movements can affect the growth of trees in response to specific growth disturbances. Although dendrogeomorphic methods are successfully used for dating other geomorphic processes, their use in landslide research is actually the most frequent. Dendrogeomorphic research on landslides is strongly influenced by general approaches of landslide signal extraction from tree-ring series of disturbed trees and by the type of landslide (varying by morphology, material and mechanism of movement). This study provides an overview of basic aspects of dendrogeomorphic research on landslides, and more specifically, it reviews basic tree-ring-based approaches of landslide dating. Presented review focuses on various landslide types and their effect on dendrogeomorphic dating. This review is built from the extensive database of all accessible dendrogeomorphic studies of landslides from 1893 to 2020. Moreover, recommendations for specific sampling and approach choice in individual landslide types are presented. Finally, limits of tree-ring-based approaches are presented, including provided proposals for further research.

scholarly journals Tree-ring based reconstruction of the seasonal timing, major events and origin of rockfall on a case-study slope in the Swiss Alps

2008 ◽  
Vol 8 (2) ◽  
pp. 203-211 ◽  
Author(s):  
D. M. Schneuwly ◽  
M. Stoffel
Keyword(s):  
Tree Ring ◽  
Cross Sections ◽  
Swiss Alps ◽  
Annual Variations ◽  
Traumatic Resin Ducts ◽  
Dormant Season ◽  
Ring Analysis ◽  
Impact Angles ◽  
Precipitation Events

Abstract. Tree-ring analysis has been used to reconstruct 22 years of rockfall behavior on an active rockfall slope near Saas Balen (Swiss Alps). We analyzed 32 severely injured trees (L. decidua, P. abies and P. cembra) and investigated cross-sections of 154 wounds. The intra-annual position of callus tissue and of tangential rows of traumatic resin ducts was determined in order to reconstruct the seasonality of past rockfall events. Results indicate strong intra- and inter-annual variations of rockfall activity, with a peak (76%) observed in the dormant season (early October – end of May). Within the growth season, rockfall regularly occurs between the end of May and mid July (21.4%), whereas events later in the season appear to be quite rare (2.6%). Findings suggest that rockfall activity at the study site is driven by annual thawing processes and the circulation of melt water in preexisting fissures. Data also indicate that 43% of all rockfall events occurred in 1995, when two major precipitation events are recorded in nearby meteorological stations. Finally, data on impact angles are in very good agreement with the geomorphic situation in the field.

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