Standards for evaluating taper estimating systems

1993 ◽  
Vol 69 (4) ◽  
pp. 438-444 ◽  
Author(s):  
A. Kozak ◽  
J. H. G. Smith
Keyword(s):  
Key Words ◽  
Forest Inventory ◽  
Variable Exponent ◽  
Douglas Fir ◽  
Variable Form

Four taper-estimating systems were evaluated for coastal Douglas-fir to demonstrate statistical and practical considerations that should be used when selecting a taper-estimating system for forest inventory purposes. The four equations compared were: Max and Burkhart's (1976) segmented polynomial, Newnham's (1988) variable-form, Ormerod's (1986) diameter-point and Kozak's (1988) variable-exponent equation. Key words: Taper, segmented polynomial, variable-form, diameter-point, variable exponent, coastal Douglas-fir

The enhanced performance of split-ring connections through prestressing

1991 ◽  
Vol 18 (5) ◽  
pp. 830-838 ◽  
Author(s):  
J. H. P. Quenneville ◽  
K. Van Dalen
Keyword(s):  
Key Words ◽  
Engineering Design ◽  
Laboratory Study ◽  
Laboratory Tests ◽  
Simple Technique ◽  
Douglas Fir ◽  
Limit States ◽  
Split Ring ◽  
Lap Splices

This paper examines the concept of enhancing the performance of timber connectors in truss joints by the introduction of transverse prestressing. The behaviour of lap splices of Douglas fir, with 63 mm split-ring connectors and end distances of 50, 100, 150, and 210 mm, was examined for various levels of prestress in a laboratory study. As well, the magnitude of the load that can be carried by the connection through friction between faying surfaces was also assessed for various levels of prestress. The simple technique used in the laboratory for introducing prestress is described. Results of the laboratory tests on 20 joint configurations are presented, and the experimentally determined strengths are compared with the calculated resistances using the provisions of CAN\CSA-086.1-M89 "Engineering design in wood (limit states design)." Key words: timber, connector, prestress, truss joint.

scholarly journals Cost of pruning Douglas-fir in coastal British Columbia

1994 ◽  
Vol 70 (1) ◽  
pp. 80-83
Author(s):  
S. A. Y. Omule ◽  
D. E. Paul ◽  
L. M. Darling
Keyword(s):  
British Columbia ◽  
Key Words ◽  
Travel Time ◽  
Douglas Fir ◽  
Time Study ◽  
Average Spacing ◽  
The Cost ◽  
Coastal British Columbia

Artificial pruning can increase the quantity of high-value clear lumber harvested from Douglas-fir, but the pruning cost per tree is relatively high. To prune a young Douglas-fir to 6 metres in one lift and two lifts took, respectively, 9.5 and 10.1 minutes in 14- and 18-year old stands with average spacing between trees of about 3 metres on flat or 0-30% south-facing slopes in coastal British Columbia. The associated costs were $2.09 and $2.22. This included minor travel time between trees, but excluded the cost of travelling to the site, selecting and marking trees to be pruned, and purchasing and maintaining the pruning equipment. Differences in pruning time between one-lift pruning and two-lift pruning, in one or two passes, were small. A D-handled saw was preferred to the more strenuous snap-cut pruner with ratchet-style pinions, based on observations on a pruning time-study of 5 operators. Key words: pruning saw, snap-cut pruner, pruning time, one-lift pruning, two-lift pruning

DISPERSION OF KAOLINITE BY WATER EXTRACTS OF DOUGLAS-FIR ASH

1984 ◽  
Vol 64 (3) ◽  
pp. 439-443 ◽  
Author(s):  
PHILIP B. DURGIN ◽  
PHILIP J. VOGELSANG
Keyword(s):  
Key Words ◽  
Chemical Constituents ◽  
Douglas Fir ◽  
Specific Adsorption ◽  
Water Extracts ◽  
Inorganic Constituents

The inorganic constituents of black and gray ash from Douglas-fir slash were analyzed to evaluate the mechanism by which ash extract disperses kaolinite. Chemical constituents promoting kaolinite dispersion were anions that increase alkalinity and are specifically adsorbed, namely orthophosphate, carbonate, hydroxyl, and me-tasilicate. Key words: Fire, specific adsorption, carbonate

Response of young Douglas-fir to urea fertilizer applied on and off snow

1994 ◽  
Vol 70 (3) ◽  
pp. 294-298
Author(s):  
Valin G. Marshall ◽  
Hugh J. Barclay
Keyword(s):  
Key Words ◽  
Pseudotsuga Menziesii ◽  
Vancouver Island ◽  
Douglas Fir ◽  
Similar Response ◽  
Forest Fertilization ◽  
Bare Ground ◽  
Urea Fertilizer ◽  
Absolute Volume

The effects of 200 kg N ha−1 applied as urea fertilizer on 50 cm of snow or on bare ground were studied in an 11-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) plantation on Vancouver Island. Analysis was done on all trees per plot and on 20 selected dominant trees per plot. Up to 2 years after fertilization, urea significantly increased absolute DBH increments over controls in all trees and the 20 selected trees per plot; response to fertilization on snow was equal to that on bare ground. Between the 3rd and 9th year following fertilization, mean DBH increments were not significantly different for any treatment. Four-year absolute volume increments were 63 and 87% greater than the controls for bare-ground and on-snow applications, respectively. A positive and quantitatively similar response is expected in wetter coastal Douglas-fir stands whether urea is applied on snow or under better conditions during other seasons. Key words: Forest fertilization, season of application, nitrogen, tree response, Pseudotsuga menziesii (Mirb.) Franco

scholarly journals Production of Douglas-Fir in the Czech Republic based on national forest inventory data

2013 ◽  
Vol 59 (No. 10) ◽  
pp. 398-404 ◽  
Author(s):  
V. Podrázský ◽  
R. Čermák ◽  
D. Zahradník ◽  
J. Kouba
Keyword(s):  
Czech Republic ◽  
Tree Species ◽  
Forest Inventory ◽  
National Forest Inventory ◽  
Douglas Fir ◽  
National Forest ◽  
Northern Red Oak ◽  
Forest Land ◽  
Land Area ◽  
The Czech Republic

This article summarizes basic estimates of productivity and trend analysis of one of the principal introduced forest tree species in the Czech Republic, i.e. Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco). As a comparison, we also examine grand fir (Abies grandis [D. Don] Lindl), northern red oak (Quercus rubra L. syn. Quercus borealis Michx.) and black locust (Robinia pseudoacacia L). This paper presents estimates of forest land area, standing volume, annual and total increments, distribution of age classes, average ages and site indexes for the period 1979–2010. All data were obtained from the national forest inventory of the Czech Republic. Korf’s growth function was used for the assessment of current and mean annual increments (CAI, MAI) of Douglas-fir compared to other tree species. Our results suggest a decline in the annual area afforested by Douglas-fir, as influenced by the State administration management choices, a low rate of an increase in the forest land area, increasing average age of the forests. On the other hand, we observed a dramatic increase in the standing volume as well as high annual increments in volume. Douglas-fir is the most productive major tree species in the Czech Republic and there is a great potential to expand its use throughout the country.

Variable-form taper functions for four Alberta tree species

1992 ◽  
Vol 22 (2) ◽  
pp. 210-223 ◽  
Author(s):  
R.M. Newnham
Keyword(s):  
Tree Species ◽  
Variable Exponent ◽  
Significant Loss ◽  
Stem Form ◽  
Data Set ◽  
Variable Form ◽  
Form Function ◽  
Taper Function ◽  
Form Model ◽  
Unbiased Estimates

The variable-form taper function was tested on a data set of 5074 trees, consisting of jack pine (Pinusbanksiana Lamb.), lodgepole pine {Pinuscontorta Dougl.), white spruce (Piceaglauca (Moench) Voss), and trembling aspen (Populustremuloides Michx.), from Alberta. When compared with the results of tests performed on the same data using the variable-exponent function and the segmented polynomial model, the variable-form model was found to be superior (based on residual mean squares) for estimating both upper stem diameter ratios and total stem volumes. The two pine species could be combined and a single taper function used without significant loss of accuracy. Stem form in two of the volume sampling regions was significantly different from that in other regions of the province, but this may have been because the samples were not representative of the two regions. The variable-form function gave accurate and unbiased estimates of both merchantable height and merchantable volume.

A variable-exponent taper equation

1988 ◽  
Vol 18 (11) ◽  
pp. 1363-1368 ◽  
Author(s):  
A. Kozak
Keyword(s):  
Variable Exponent ◽  
Computing Time ◽  
Variable Form ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Taper Function ◽  
Taper Equation ◽  
Taper Equations ◽  
Different Parts

A different approach to fitting taper equations has been developed, which eliminates the necessity of using several functions to predict diameter inside bark at different parts of the stem. The variable form taper function is easy to develop and saves computing time. For the data used in this study, it predicted tree profile as a function of height, diameter at breast height, and height from the ground with less bias than many of the taper-estimating systems found in the literature.

Multislice imaging of gastrointestinal stromal tumors

2018 ◽  
pp. 3-14
Keyword(s):  
Computed Tomography ◽  
Key Words ◽  
Gold Standard ◽  
Gastrointestinal Stromal Tumors ◽  
Mesenchymal Tumors ◽  
Stromal Tumors ◽  
Preferential Localization ◽  
Multislice Imaging ◽  
Computed Tomography Diagnosis

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the digestive tract (1%). These tumors express the CD 117 in 95% of cases. The stomach is the preferential localization (70%). Diagnosis is difficult and sometimes late. Progress of imaging has greatly improved the management and the prognosis. Computed tomography (CT) is the gold standard for diagnosis, staging, and treatment follow-up. The increasing recognition of GIST’s histopathology and the prolonged survival revealed some suggestive imaging aspects. Key words: gastro-intestinal stromal tumors; computed tomography; diagnosis

METHODS OF CONSULTING ON STUDYING THE DEGREE OF MOISTURE SUPPLY OF SLOPE LANDS FOR AGRICULTURAL PRODUCTION IN AZERBAIJAN

2018 ◽  
Author(s):  
Prof.RAE Aliev Z.H.
Keyword(s):  
Key Words ◽  
Agricultural Production ◽  
Soil Ecology ◽  
Arable Soil ◽  
Clean Technology ◽  
Agricultural Product ◽  
Current Information ◽  
Moisture Supply ◽  
Managerial System

The current information on moisture and the temperature of the ground in managerial system by production to agricultural product necessary, in the first place, for taking the operative decisions at development ecological clean technology irrigation under growing agricultural cultures to achieve the maximum harvest. Key words: aerospace methods, COW, moisture, moisture test, arable, soil, ecology, vafer humidity, drill, graduation, tool, etc.

PELAKSANAAN HUKUM KEWARISAN ISLAM DI PENGADILAN AGAMA BANTEN

ALQALAM ◽  
2013 ◽  
Vol 30 (1) ◽  
pp. 158
Author(s):  
Yusuf Somawinata
Keyword(s):  
Key Words ◽  
Islamic Law ◽  
Survey Methods ◽  
Adopted Children ◽  
Inheritance Law ◽  
Library Research ◽  
The Ideal

This article aims at describing the obseroance of wasiat wajibah (compulsory bequeathment) in the Islamic court of Banten, analyzing the provision of the substitute heir and adopted children in the Compilation of  Islamic Law (KHI). In addition, the ideal laws to manage the innheritance rules in Indonesia. This article is library research by using doctrinal approach and using case study and survey methods. The data was, then, analyzed by using analytical descriptive and analytical correlative methods. The result showed that the observance of wasiat wajibah in the Islamic court of  Banten employed by judges is by using the Mawali Hazairin’s Doctrine. The criteria of the adoption of substitute heir and adopted children in the KHI is the attempts of Ulama and many judgees junst in giving legal justice and certainty to the society.   Key Words: Islamic Inheritance Law, Compilation of Islamic Law, Islamic court of  Banten

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