scholarly journals Field and Computer Application of Mesavage and Girard Form Class Volume Tables

1998 ◽  
Vol 22 (2) ◽  
pp. 81-87 ◽  
Author(s):  
Robert C. Parker
Keyword(s):  
Regression Model ◽  
Iterative Procedure ◽  
Computer Applications ◽  
Tree Size ◽  
Computer Application ◽  
Form Class ◽  
Single Tree ◽  
Standing Trees ◽  
Taper Equation ◽  
Volume Functions

Abstract Mesavage and Girard form class volume tables for estimating board foot volume of standing trees remain the most widely used volume tables in the East and South even though newer, more versatile and sophisticated volume functions are available. The volume tables are being misused by foresters because the merchantability standards of the average, upper-log taper table used to derive the volume tables does not show that merchantable top diameters and form class applications require appropriate sampling and accurate measurement of form on selected trees. The original upper-log tapers, developed from averages of actual tree measurements and ocular estimates, were fitted to a regression model to smooth the inconsistencies of the table values. The resulting Mesavage and Girard "taper equation" is used to obtain upper stem diameters for trees of known Girard form class, dbh, and merchantable height. The taper equation shows that top-limit diameter increases with both tree size (dbh and height) and Girard form class, and any attempt to apply form class volume tables to a fixed-top diameter on inventory trees would produce erroneous cruise volumes. The derived taper equation can be used in an iterative procedure during computer applications to obtain single tree volumes as the sum of log segment volumes for segments of user-defined length. A hierarchy of suggested form class application options is presented along with suggestion sampling, measurement, and stratification procedures. South. J. Appl. For. 22(2):81-87.

scholarly journals Investigations on the Effects of Seasonal Temperature Changes on the Electrical Resistance of Living Trees

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 550 ◽  
Author(s):  
Xiaoquan Yue ◽  
Lihai Wang ◽  
Xiaolong Shi ◽  
Mingxian Xu ◽  
Zhiming Zhu
Keyword(s):  
Moisture Content ◽  
Regression Model ◽  
Cross Sections ◽  
Electrical Resistance ◽  
Freezing Point ◽  
Seasonal Temperature ◽  
Populus Simonii ◽  
Standing Trees ◽  
Different Temperatures ◽  
The Cross

In order to use the electrical resistance method to accurately and timely detect and evaluate the internal decay defects of living trees, the effects of the seasonal temperature and moisture content on the electrical resistance of standing trees were investigated. At the Northeast Forestry University Experimental Forest Farm, Harbin, Heilongjiang Province of China, Populus simonii Populus simonii Carr. and Larix gmelinii (Rupr.) Rupr. were selected as the objects and the electrical resistance of standing trees was tested through different seasons from December 2016 to December 2017. Meanwhile, the effects of changes in the seasonal temperatures (−20 to −10 °C, −10 to −5 °C, −5 to 0 °C, 0 to 5 °C, 5 to 10 °C, 10 to 15 °C, 15 to 25 °C) as well as changes in the moisture content (MC) (Populus simonii, MC ≥ 103%; Larix gmelinii, MC ≥ 77.5%) on the electrical resistance in the cross-sections of living trees were studied. The influence of temperature at different moisture contents, the moisture content at different temperatures, and their combined effects on electrical resistance were analyzed, following which a regression model was also established. The obtained results indicated that ambient temperature had a significant effect on the average value of electrical resistance in the cross-section of living trees when temperatures were below the freezing point. There was a sudden discontinuity near the freezing point, and logR (logarithm value of electrical resistance) in the cross-sections of sound trees and decayed trees changed in a similar trend with variations in the temperature. While the effect of moisture content on logR in the cross-sections of threes was insignificant at different temperatures because of the moisture content above FSP (fiber saturation point). It indicated that the temperature and moisture content had interactive effects on logR in the cross-sections. The binary linear regression model between moisture content, temperature, and logR was highly fitted with a correlation coefficient (R2) higher than 0.8. The outcome of this investigation indicates that when non-destructive testing is performed on living trees using electrical resistance at different seasonal temperatures, the measured results need to consider both the temperature and moisture content. For practical work, it is not recommended to consider testing living trees near the freezing point temperature using the electrical resistive tomography. Below the freezing point, the electrical resistance changes with temperature greatly relative to the normal temperature. Therefore, when performing the detection of electrical resistance, it is necessary to calibrate the effects of temperature

Integrating Semiotics Perception in Usability Testing to Improve Usability Evaluation

2013 ◽  
pp. 145-169 ◽  
Author(s):  
Muhammad Nazrul Islam ◽  
Franck Tétard
Keyword(s):  
User Interfaces ◽  
Usability Testing ◽  
End Users ◽  
Usability Evaluation ◽  
Computer Applications ◽  
Computer Application ◽  
Semiotic Analysis ◽  
Usability Problems ◽  
Intuitive Interface ◽  
Methodological Guidelines

User interfaces of computer applications encompass a number of objects such as navigation links, buttons, icons, and thumbnails. In this chapter, these are called interface signs. The content and functions of a computer application are generally directed by interface signs to provide the system’s logic to the end users. The interface signs of a usable application need to be intuitive to end users and therefore a necessary part of usability evaluation. Assessing sign intuitiveness can be achieved through a semiotic analysis. This study demonstrates how a semiotic assessment of interface signs’ intuitiveness yielded a number of benefits. For instance, (i) it provides an overall idea of interface signs’ intuitiveness to the end users to interpret the meaning of interface signs, (ii) it assists in finding usability problems and also in (iii) recommending possible solutions, (iv) provides background for introducing guidelines to design user-intuitive interface signs, (v) helps in constructing heuristic checklist from semiotics perspective to evaluate an application, (vi) no additional resource and extra budget are needed. This study also presents a list of methodological guidelines to obtain the perceived benefits of integrating semiotic perception in usability testing for practitioners.

scholarly journals On the almost sure convergence of a general stochastic approximation procedure

1986 ◽  
Vol 34 (3) ◽  
pp. 335-342 ◽  
Author(s):  
S. N. Evans ◽  
N. C. Weber
Keyword(s):  
Regression Model ◽  
Stochastic Approximation ◽  
Iterative Procedure ◽  
Almost Sure Convergence ◽  
Approximation Procedure ◽  
Stochastic Approximation Procedure ◽  
General Stochastic

A set of conditions for the almost sure convergence of a stochastic iterative procedure is given. The conditions are framed in terms of the behaviour of the random adjustment made the n-th step rather than in terms of some underlying regression model.

scholarly journals Genetic Structure of Heterobasidion annosum in White Fir Mortality Centers in California

1999 ◽  
Vol 89 (7) ◽  
pp. 546-554 ◽  
Author(s):  
Matteo Garbelotto ◽  
Fields W. Cobb ◽  
T. D. Bruns ◽  
William J. Otrosina ◽  
Tina Popenuck ◽  
...  
Keyword(s):  
Heterobasidion Annosum ◽  
Mixed Conifer ◽  
Tree Diameter ◽  
Single Tree ◽  
White Fir ◽  
Standing Trees ◽  
Local Genotypes ◽  
Study Sites ◽  
Individual Trees ◽  
Vegetative Spread

The structure of Heterobasidion annosum populations was studied in 15 mixed-conifer sites in central and northern California. Study sites displayed mortality of white fir trees in enlarging discrete patches (mortality centers). At each site, fungal genotypes were defined by somatic compatibility tests. In two sites, further genetic and molecular analyses were performed on field genotypes and on homokaryons obtained by dedikaryotization of field heterokaryons. Isolates were found to be colonizing mostly the roots and the bole sapwood of white fir trees, and no significant infections of other tree species were observed. Each mortality center was characterized by the presence of several fungal genotypes, all belonging to the S intersterility group. Both homokaryotic and heterokaryotic strains were present in all sites. Multiple genotypes were retrieved in individual trees or stumps. Out of 228 fungal genotypes, 86% were found only within a single tree or stump, while 14% had spread to adjacent trees. The two largest genotypes had diameters of 9 and 10 m, and had colonized five and nine trees, stumps, or both, respectively. The maximum distance between two adjacent trees colonized by the same genotype was 6 m, and a highly significant correlation was found between tree diameter and distance of fungal “vegetative” spread. The largest clones were found in areas characterized by high tree and stump densities, and secondary spread of the fungus was more significant in denser stands. In most cases, original infection courts of existing genotypes could be traced to standing trees and not to stumps. The genetic analysis performed in two mortality centers revealed that most local genotypes had different mating alleles, and thus originated from unrelated basidiospores. In a few cases, the same mating allele was shared by two heterokaryons (n+n genome) or by a homokaryon (n genome) and a heterokaryon. Molecular analysis showed that nuclei bearing the same mating allele were identical, providing evidence that the two nuclei forming heterokaryons can act independently in the field and can be shared among isolates, presumably via di-mon mating or by separate matings of different portions of widespread homokaryons.

scholarly journals Form Class and Its Use in Estimating Sawtimber Volume of Sugar Maple Trees

2010 ◽  
Vol 27 (2) ◽  
pp. 75-77
Author(s):  
Ralph D. Nyland ◽  
Diane Kiernan
Keyword(s):  
New York ◽  
Sugar Maple ◽  
Prediction Equation ◽  
Diameter Class ◽  
Form Class ◽  
Standing Trees ◽  
Class Average ◽  
Using Data ◽  
Estimate Form

Abstract The Mesavage-Girard form class for a composite of 242 sugar maple sawtimber trees in New York averaged 82 (±5.3), differing significantly from the regional average form class of 79 originally recommended in the Mesavage-Girard form class volume tables. Also, for 8 of 16 stands, the measured form class differed significantly from the recommended regional average. Findings suggest a need to estimate form class for each tree when making an inventory of sawtimber volume. A regression analysis using data from the 242 sample trees provided a prediction equation for estimating diameter inside bark at 17 ft height on the basis of dbh. That allows determination of a unique Mesavage-Girard form class for each diameter class of sugar maple trees and use of that diameter class average when computing the board-foot volume of standing trees.

Spruce Beetle Aggregated by the Synthetic Pheromone Frontalin

1973 ◽  
Vol 3 (4) ◽  
pp. 486-494 ◽  
Author(s):  
E. D. A. Dyer
Keyword(s):  
Tree Size ◽  
Southern Pine Beetle ◽  
Southern Pine ◽  
Synthetic Pheromone ◽  
Spruce Beetle ◽  
Pine Beetle ◽  
Synthetic Attractant ◽  
Standing Trees

Frontalin, a synthetic attractant developed from the southern pine beetle (Dendroctonusfrontalis Zimm.), induced spruce beetle (D. rufipennis Kirby) attacks on preselected spruce trees destined for harvest, and adjacent trees. If baited trees were treated with insecticide, spruce beetles and predators (Thanasimusundatulus Say) were killed. Female Dendroctonus predominated on frontalin-baited trees. Some baited trees, unprotected by insecticide, were killed by beetle attacks but many resisted attacks and prevented beetle broods from developing. Green windfall trees were attacked whether or not frontalin was used on adjacent standing trees. Distance between attractant, and attacked unbaited trees appeared to be related to tree size.

scholarly journals A Physiologically Based Pharmacokinetic (PBPK) Model of Vitamin B-6 Metabolism in the Mouse Incorporated With Visualization of Complex Compartmental Models

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 1307-1307
Author(s):  
Stephen Coburn ◽  
Joel Stauffer ◽  
Kimberley Grobien ◽  
Beomjin Kim ◽  
Douglas Townsend
Keyword(s):  
Compartmental Model ◽  
Growth Curves ◽  
Circulation Model ◽  
Computer Applications ◽  
Computer Application ◽  
Vitamin B ◽  
Mouse Urine ◽  
Funding Sources ◽  
Complex Models ◽  
Endogenous Metabolites

Abstract Objectives To develop a compartmental model which describes vitamin B-6 metabolism in the blood and tissues of the mouse under a variety of circumstances and to develop a computer application which can utilize the data to display the movement of tracer through the various compartments. Methods A circulation model was developed. Literature data from vitamin B-6 feeding studies and tracer experiments were used to develop an appropriate compartmental model using the SAAM II program (The Epsilon Group, Charlottesville, VA). A web-based application transforms the mass and flux data into intuitive and interactive graphical illustrations. Results Describing the interconversions between pyridoxine, pyridoxine 5’-phosphate, pyridoxal, pyridoxal 5’-phosphate, pyridoxamine, pyridoxamine 5’-phosphate and 4-pyridoxic acid in multiple tissues required 231 compartments. The largest amount of data deals with liver and brain. The model includes less detailed information on plasma, erythrocytes, gut, bone, muscle, heart, kidney, skin, adipose tissue and lung. The model includes adjustments to food intake, water intake, cardiac output, binding sites and Vmax values for enzymes based on the specified body weight of experimental animals. We did not include growth curves at this time. The model uses two parallel systems to monitor the steady state of endogenous metabolites as well as following tracer administration. Binding mechanisms are included to provide conservation of vitamin B-6 when intake is reduced. The model provides reasonable agreement with literature data on various vitamin B-6 intakes as well as oral and intravenous administration of tracer. It also reveals some areas which need clarification. For example, we have not found any detailed analysis of vitamin B-6 metabolites in mouse urine. There is little pyridoxic acid in plasma or urine suggesting that pyridoxic acid may not be the primary end product for vitamin B-6 in the mouse. The visualization application shows changes in the content of all 231 compartments over time illustrating the value of such computer applications in the interpretation of large, complex models. Conclusions This model facilitates the simulation of various dietary and physiological conditions on vitamin B-6 metabolism in mice. We hope to adapt it to rats, pigs and humans. Funding Sources Purdue University Fort Wayne.

scholarly journals Re-framing Research in Human-Computer Interaction from the Point-of-View of Activity Theory?

1993 ◽  
Vol 22 (443) ◽  
Author(s):  
Susanne Bødker
Keyword(s):  
Human Computer Interaction ◽  
Activity Theory ◽  
Real Life ◽  
Point Of View ◽  
Computer Applications ◽  
Computer Application ◽  
Mapping Technique ◽  
Specific Situation ◽  
Alternative Approach ◽  
Computer Interaction

<p>Within human-computer interaction cognitive science is today the leading approach. Yet its position is threaded philosophically as well as from within the field. Most attempts to re-frame human-computer interaction from within the field are minor revisions to the traditional theoretical basis, still without much to say about real-life computer applications. In this paper I shall present and discuss an alternative approach based on activity theory.</p><p>The following summarizes the theoretical anchor points:</p><p>Activity is mediated. That artifacts mediate use means that we are normally not aware of them as such in use, they are transparent to us. Artifacts are seen as historical devices.</p><p>Although collective, each activity is conducted through actions of individuals.</p><p>Activities are not taking place in isolation but interwoven with other activities. Artifacts may be the instruments of a web of activities. The concepts of breakdowns and focus shifts are used in the further analysis of specific computer applications in use, and a mapping technique for such analysis is developed. Based on an example I take the first steps towards a more contex\-tualized analysis of human-computer interaction. The human activity framework has provided a vehicle for bringing together an overall analysis of work and use of computer technology with a detailed analysis of human-computer interaction. It provides a way of understanding the relations between the overall socio-political conditions of work and the specific use of the specific computer application in a specific situation. What actually goes on may be analysed from many different levels of activity, where the actual actors are different, and maybe even different from those who conduct the specific actions.</p>

scholarly journals Analysis of the Frequency of Academic Staff and Students` Use of Information and Communication Technology (ICT) in Katsina State College of Education

2012 ◽  
Vol 4 (11) ◽  
pp. 558-562
Author(s):  
Mbaba A.E.
Keyword(s):  
Information And Communication Technology ◽  
Communication Technology ◽  
Academic Staff ◽  
College Of Education ◽  
Daily Basis ◽  
Computer Applications ◽  
Computer Application ◽  
State College ◽  
Wide Range ◽  
Information And Communication

The paper analyze the frequency of academic staff and students use of information and communication technology {Ict} in Katsina State College of Education, it explore the ability of staff and students in computer application 114 academic staff and 1995 students were engaged in the study. A survey research design was used; the data collected was analyzed using percentage to present the responses. 4 point Likert-scale was used, while a mean of 2.50 was adopted to determine the higher and lower participation in the use of ICT and ability in computer application. The finding show that the use of ICT in the College is high [m=2.78 higher than m=2.50]. The study also indicated that the academic staff are more competent in the use of wide range of computer applications than students are [m=3.08and 2.56 respectively] the study reveals that the staff and students actually engaged in the use of ICT almost on a daily basis for both school learning and individual use. The researchers therefore recommend that this study should be carried out in all the tertiary institutions in Nigeria to clarify the uncertainty of the frequency of ICT use in Nigeria schools.

scholarly journals Four Different Perspectives on Human-Computer Interaction

1985 ◽  
Vol 14 (203) ◽  
Author(s):  
John Kammersgaard
Keyword(s):  
Human Computer Interaction ◽  
Final Section ◽  
Computer Applications ◽  
Computer Application ◽  
Multiple Perspectives ◽  
Systems Perspective ◽  
The Media ◽  
Computer Interaction

In this paper the value of a multiperspective view on the use of computers is stressed. It is argued that the ability to apply more than one perspective is valuable both to designers of computer applications, to researchers dealing with human-computer applications, and to users of a particular computer application. As a means for that the systems perspective, the dialogue partner perspective, the tool perspective, and the media perspective are represented. All four perspectives are primarily characterized in relation to human-computer interaction, and the characterizations are based on a common set of concepts presented at the start of the paper. In the final section the value of applying multiple perspectives is illustrated by means of a few examples.

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