scholarly journals Reliability of Noninvasive Sonic Tomography for the Detection of Internal Defects in Old, Large Trees of Abies holophylla Maxim

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1131
Author(s):  
Jiwon Son ◽  
Gwanggyu Lee ◽  
Jinho Shin
Keyword(s):  
Regression Analysis ◽  
Cross Section ◽  
Explanatory Power ◽  
Strong Wind ◽  
Internal Defects ◽  
Noninvasive Technique ◽  
Noninvasive Measurements ◽  
Large Trees ◽  
Invasive Method ◽  
Heavy Snow

Internal decay and cavities in wood are known to reduce the structural functionality of trees. Such damage may lead to detrimental effects not only on the wood, but also on humans. This is especially the case with old, large trees that are more vulnerable to heavy snow and strong wind. Thus, preventative management (e.g., detecting internal wood defects) is essential. The present study investigated the reliability of noninvasive measurements using sonic tomography (SoT) to detect internal defects in Abies holophylla Maxim. trees and compared the results with measurements using the invasive method of resistance microdrilling (RM). The tomograms were visually compared with tree cross-section images. The results of SoT and RM showed no significant differences, while the explanatory power, as determined by a regression analysis, were considerably high at 67% with a positive correlation between the two methods. In comparison to the cross-section images, the tomograms were found to reflect the size and position of internal decay, although the detected size tended to be larger than the actual decay area. Our findings indicate SoT as a promising noninvasive technique for detecting internal defects in A. holophylla trees.

ESTIMATION OF GROWTH – TIME TEMPERATURE CHARACTERISTICS FOR ISOLATES OF FOMES PINI, A HEART ROT FUNGUS

1964 ◽  
Vol 42 (12) ◽  
pp. 1635-1652 ◽  
Author(s):  
Lee A. Paine ◽  
Gideon Schwarzbart ◽  
William G. O'Regan
Keyword(s):  
Regression Analysis ◽  
Cross Section ◽  
Growth Pattern ◽  
Storage Temperature ◽  
Three Dimensional ◽  
Douglas Fir ◽  
Growth Time ◽  
Optimum Temperature ◽  
Analysis Techniques ◽  
White Fir

Regression analysis techniques were applied to an estimation of three-dimensional surfaces representing the growth of Fomes pini as a function of time and temperature. These methods were judged to be valuable in their economy of data and in their provision of readily available plotting points for any desired cross section of the surface.The growth pattern of F. pini taken from Douglas fir was distinct from that of the form of F. pini found on nearby white fir. Growth of isolates from Douglas fir was more than twice that of white fir isolates after 18 days at near-optimum temperatures on malt agar. Estimates of growth trends and optimum temperatures were examined both for individual isolates of F. pini and for averages of isolates from the two host species, Douglas fir and white fir. Results suggest that chronological changes in the optimum temperature may be affected by the relation between the storage temperature preceding initial measurements and the terminal optimum temperature.

Finite Element Analysis for the Collapse Accident of a 110kV Transmission Tower

2014 ◽  
Vol 986-987 ◽  
pp. 927-930
Author(s):  
Yi Zhu ◽  
Bo Li ◽  
Hao Wang ◽  
Kun Li
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cross Section ◽  
Strong Wind ◽  
Transmission Tower ◽  
Element Analysis ◽  
Straight Line ◽  
The Finite Element Analysis

Put the finite element analysis of line tower coupling modeling to the collapse of a 110 kV line straight-line tower, study the effect of strong wind on transmission tower and wire. The results show that under the action of strong wind, the material specification selected by the part of the rods on the type of tower is lower, cross section is smaller, the principal material of tower will be instable and flexional under the compression, resulting in tower collapsed.

scholarly journals The Prognostic Significance of the Alterations of Cardiovascular Hemodynamics in Patients With Pulmonary Arterial Hypertension: A Meta-regression Analysis of Randomized Controlled Trials

2021 ◽  
Author(s):  
Shih-Hsien Sung ◽  
Wan-Yu Yeh ◽  
Chern-En Chiang ◽  
Chi-Jung Huang ◽  
Wei-Ming Huang ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Pulmonary Arterial Hypertension ◽  
Explanatory Power ◽  
Controlled Trials ◽  
Hemodynamic Changes ◽  
Randomized Controlled ◽  
Clinical Events ◽  
Pulmonary Arterial ◽  
Meta Regression ◽  
Meta Regression Analysis

Abstract Background: Hemodynamic assessment in patients with pulmonary arterial hypertension (PAH) is essential for risk stratification and pharmacological management. However, the prognostic value of the hemodynamic changes after treatment is less well established. Objectives: We investigated the prognostic impacts of the changes in hemodynamic indices, including mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), right atrial pressure (RAP) and cardiac output index (CI). We conducted this systematic review with meta-regression analysis on existing clinical trials.Methods:We searched and identified all relevant randomized controlled trials from multiple databases. An analogous R2 index was used to quantify the proportion of variance explained by each predictor in the association with PAH patients’ prognosis. A total of 20 trials and 3,263 individuals were enrolled. Results:The changes in mPAP, PVR, RAP and CI were all significantly associated with the change in 6MWD (∆6MWD). The change in mPAP was with the highest explanatory power for ∆6MWD (R2 analog=0.739). Additionally, the changes in mPAP, PVR and CI were independently predictive of adverse clinical events. The change in mPAP had the highest explanatory power for the clinical events (R2 analog =0.911). Furthermore, the change in PVR was with the highest explanatory power for total mortality of PAH patients (R2 analog =0.594). Conclusion:Hemodynamic changes after treatment, including mPAP, PVR, CI and RAP, were significantly associated with adverse clinical events or mortality in treated PAH patients. It is recommended that further studies be conducted to evaluate the changes in hemodynamic indices to guide drug titration.Trial registration number: PROSPERO; No.: CRD42019125157; URL: https://www.crd.york.ac.uk/PROSPERO/ (Date of registration: 14/03/2019)

scholarly journals Factors associating with disability of non-specific low back pain in different subgroups: A hierarchical linear regression analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takahiro Miki ◽  
Daisuke Higuchi ◽  
Tsuneo Takebayashi ◽  
Mina Samukawa
Keyword(s):  
Regression Analysis ◽  
Low Back Pain ◽  
Back Pain ◽  
Pain Intensity ◽  
Psychosocial Factors ◽  
Self Efficacy ◽  
Explanatory Power ◽  
Low Back ◽  
Acute Group ◽  
Pain Catastrophising

AbstractThis study aimed to explore factors associating with disability, which means physical impairment affecting a person’s mobility, capacity, stamina, or agility, of non-specific low back pain (NSLBP) of the acute and non-acute groups. Two hundred thirty-five patients with NSLBP of less than 8 weeks’ duration as acute groups (n = 124) and more than 8 weeks’ duration as non-acute group (n = 111) were recruited. It was collected data on pain intensity, disability and psychosocial factors, including pain catastrophising, fear of movement and pain self-efficacy. Disability was measured Roland Morris Disability Questionnaire. A hierarchical multiple regression analysis was performed to analyse factors associating with disability of the acute and non-acute groups. The Result was that explanatory power increased with each additional variable of the order of demographic characteristics, pain intensity and psychosocial factors for both groups. Pain intensity, pain catastrophising and pain self-efficacy had significant explanatory power, with pain self-efficacy having the most significant association on the acute group. Only pain self-efficacy having the most significant association on disability of the non-acute group. In conclusion, the factors associating with disability differed depending on the duration of the disease, and pain self-efficacy might be one of the factors associating with disability of patients with NSLBP.

scholarly journals ANALISIS PENGARUH SOSIAL EKONOMI TERHADAP PENGELOLAAN SAMPAH DI SUMATERA BARAT (STUDI KASUS DAERAH PERKOTAAN)

2020 ◽  
Vol 2 (1) ◽  
pp. 107
Author(s):  
Nesyana Dewi ◽  
Melti Roza Adry
Keyword(s):  
Logistic Regression ◽  
Regression Analysis ◽  
Waste Management ◽  
Cross Section ◽  
Urban Areas ◽  
Secondary Data ◽  
Cross Section Data ◽  
Income Per Capita ◽  
Section Data ◽  
Per Capita

This study aims to determine the effect of education, income per capita, age and knowledge on waste management in urban areas West Sumatera. This study uses secondary data in the form of cross section data of urban West Sumatera. Data obtained from BPS- Susenas West Sumatera. This study uses logistic regression analysis. The result of this study indicate that (1) education has not significant effect on waste management in urban areas West Sumatera (2) income per capita has not significant effect on waste management  in urban areas West Sumatera (3) age has not significant effect on waste management in urban areas West Sumatera (4) knowledge has a significant effect on waste management in urban areas West Sumatera

scholarly journals Conventional and Current way of Interpretation and Cost Forecasting

2020 ◽  
Vol 1 (6) ◽  
pp. 30-33
Author(s):  
Shahin ripon Nazmul ◽  
Riyaaz Sanjoy
Keyword(s):  
Regression Analysis ◽  
Production Process ◽  
Cross Section ◽  
Series Data ◽  
Cross Section Data ◽  
Short Term ◽  
Section Data ◽  
Production Factors ◽  
Cost Forecasting

This study discuses Short-term cost interpretation, regression analysis with time-series data, long term cost interpretation, Regression analysis using cross-section data, cost forecasting and Changes in the productivity of production factors. Short-term cost interpretation lead to short-term decisions, the concept of incramental costs has a very important role which includes variable costs and changes in fixed costs.  Long term cost interpretation to analyze the production function of several different firms, long-run cost estimates can be used. Based on these conditions, the estimation of long-term costs uses cross-section data. Forecasting costs for various levels of output in the coming period requires an assessment of changes in the efficiency of the production process physically, plus changes in the prices of production factors used in the production process.

scholarly journals Moderating Effect of Mindfulness on the Influence of Stress on Depression According to the Level of Stress among University Students in South Korea

2020 ◽  
Vol 17 (18) ◽  
pp. 6634
Author(s):  
Kwang-Hi Park ◽  
Hyunlye Kim ◽  
Jaehee Kim
Keyword(s):  
Regression Analysis ◽  
University Students ◽  
South Korea ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Life Stress ◽  
Mental Health Problems ◽  
Explanatory Power ◽  
Moderating Effect ◽  
The Impact

Stress and depression are representative of the mental health problems of university students worldwide. This cross-sectional study explored the moderating effect of mindfulness on the influence of stress on depression according to the degree of life stress. The participants were 738 university students in years 2–4 in five 4-year universities in South Korea. Depression was positively correlated with stress and negatively with mindfulness at a statistically significant level. In multiple regression analysis, stress was found to have an effect by increasing depression, and mindfulness by relieving depression. In the moderated multiple regression analysis, mindfulness had a moderating effect on the impact of stress on depression only in low-stress groups, showing that the interaction of stress with mindfulness was significantly negative (β = −0.11, t = −2.52, p = 0.012) and the inclusion of this interaction significantly increased the explanatory power for depression variation (F change 6.36, p = 0.012) in the full model. In conclusion, we suggest considering stress levels in the development of mindfulness-based intervention strategies to effectively manage the depression of university students.

Applications of RiverCAT in the Field Measurement of Reservoirs

2013 ◽  
Vol 333-335 ◽  
pp. 226-229
Author(s):  
He Fang Jing ◽  
Yi Tian Li
Keyword(s):  
Regression Analysis ◽  
Water Supply ◽  
Cross Section ◽  
Measurement System ◽  
Field Measurement ◽  
River Discharge ◽  
Analysis Method ◽  
Quadratic Formula ◽  
Fully Integrated ◽  
The Relationship

SonTek’s Riversurveyor Catamaran (the RiverCAT) is a fully integrated river discharge measurement system. In this paper, the RiverCAT is applied to measure the topography under water in a middle industry water supply reservoir. The whole measurement process is introduced. Area of each cross-section is calculated with complex trapezoidal quadratic formula, and the capacity of the reservoir is computed with complex prismaid quadratic formula. The relationship between capacity and water level is researched by regression analysis method.

Sign in / Sign up

Export Citation Format

Share Document