scholarly journals Improved Hough Transform and Total Variation Algorithms for Features Extraction of Wood

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 466
Author(s):  
Weiwei Du ◽  
Yarui Xi ◽  
Kiichi Harada ◽  
Yumei Zhang ◽  
Keiko Nagashima ◽  
...  

Research shows that the intensity impact factors of wood, such as late timber ratio, volume density and the intensity of itself, correlate with the width of wood annual rings. Therefore, extracting wood annual ring information from wood images is helpful for evaluating wood quality. During the past few years, many researchers have conducted defect detection by studying the information of wood images. However, there are few in-depth studies on the statistics and calculation of wood annual ring information. This study proposes a new model combining the Total Variation (TV) algorithm and the improved Hough transform to accurately measure the wood annual ring information. The TV algorithm is used to suppress image noise, and the Hough transform is for detecting the center of the wood image. Moreover, the edges of wood annual rings are extracted, and the statistical ring information is calculated. The experimental results show that the new model has good denoising capability, clearly extract the edges of wood annual rings and calculate the related parameters from the indoor wood images of the processed logs and the unprocessed low-noise logs.

IAWA Journal ◽  
1998 ◽  
Vol 19 (2) ◽  
pp. 181-189 ◽  
Author(s):  
Keiko Kuroda

Trunks of Chamaecyparis obtusa were injured to examine seasonal differences in traumatic resin canal formation in secondary phloem. Even after wounding during winter, differentiation of axial parenchyma into epithelium was initiated, and vertical resin canals formed. After winter wounding, resin canal development was slower and the tangential extent of resin canals was narrower than after spring wounding, and it took one to two months until resin secretion began. After spring wounding, the sites of resin canal formation were the 1- and 2-year-old annual rings of phloem. In August, the location of resin canal formation shifted into the current and 1-year-old annual ring. Resin canals never formed in secondary phloem areas that were 3 or more years old. In C. obtusa trunks that are affected by the resinous stem canker, numerous tangentiallines of resin canals are found throughout the phloem, not just recent and 1- to 2-year-old phloem. The present research indicates that these many lines of resin canals were not formed at one time, and that the stimuli that induce traumatic resin canals must occur repeatedly over many years. The data on artificial wounding effects are useful for understanding resinous stem canker.


IAWA Journal ◽  
2004 ◽  
Vol 25 (2) ◽  
pp. 129-140 ◽  
Author(s):  
Yuzou Sano

The structure of intervascular pits, located at the boundary between the outermost and the second youngest annual rings in Betula platyphylla var. japonica and Fraxinus mandshurica var. japonica was examined by field-emission scanning electron microscopy. Unilaterally compound pits were present in the intervascular common wall at the annual ring boundary in both species. On the outer annual ring side of the unilaterally compound pits, outlines of pit membranes were curved or trifoliate, and each pit aperture was often elongated and curved. The porosity of the intervascular pit membranes differed between the two species. In B. platyphylla var. japonica, microfibrils were loosely packed in the peripheral region of each pit membrane, and openings of up to 300 nm in width were observed. By contrast, microfibrils were densely packed throughout the entire pit membranes in F. mandshurica var. japonica, and no openings perforating the pit membranes entirely were found. In addition, each species exhibited some unique features. In B. platyphylla var. japonica, extensive ethanol-soluble material was detected not only in the intervascular pits but also on scalariform perforation plates. In F. mandshurica var. japonica, we observed fine curly fibrils of unkown chemical composition in the intervascular pit membranes.


Radiocarbon ◽  
1961 ◽  
Vol 3 ◽  
pp. 77-80 ◽  
Author(s):  
H. Godwin ◽  
E. H. Willis

In continuance of investigations upon successive annual crops of oats reported in Radiocarbon Supplement, Volume 2, we undertook the analysis of successive annual rings of a tree that had been growing throughout the period covered by the oat-crop assays, namely 1953 to 1959. The selected tree was a straight-boled specimen of Populus nigra from the Forestry Commission's plantations at Santon Downham, near Thetford, Norfolk. It had been planted in 1929 and was felled on 21 October, 1959. Shortly afterwards, it was brought into the laboratory and sawn into slices just over 1 in. thick. The surfaces having been smoothed, the annual-ring contacts were marked, and within each annual ring the inner (spring) wood was marked off from the outer (autumn) wood. The tree had been chosen as one exhibiting rapid growth and it proved fairly easy to dissect off with a chisel all the separate half-rings between spring 1953 and the end of 1959. In the event, activities were determined only upon four of the half or whole rings.


2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Jianguang Zhu ◽  
Kai Li ◽  
Binbin Hao

Total variation regularization is well-known for recovering sharp edges; however, it usually produces staircase artifacts. In this paper, in order to overcome the shortcoming of total variation regularization, we propose a new variational model combining high-order total variation regularization and l1 regularization. The new model has separable structure which enables us to solve the involved subproblems more efficiently. We propose a fast alternating method by employing the fast iterative shrinkage-thresholding algorithm (FISTA) and the alternating direction method of multipliers (ADMM). Compared with some current state-of-the-art methods, numerical experiments show that our proposed model can significantly improve the quality of restored images and obtain higher SNR and SSIM values.


2019 ◽  
Vol 13 ◽  
pp. 174830181983305 ◽  
Author(s):  
Yafeng Yang ◽  
Donghong Zhao

In this paper, we propose a model that combines a total variation filter with a fractional-order filter, which can unite the advantages of the two filters, and has a remarkable effect in the protection of image edges and texture details; simultaneously, the proposed model can eliminate the staircase effect. In addition, the model improves the PSNR compared with the total variation filter and the fractional-order filter when removing noise. Zhu and Chan presented the primal-dual hybrid gradient algorithm and proved that it is effective for the total variation filter. On the basis of their work, we employ the primal-dual hybrid gradient algorithm to solve the combined model in this article. The final experimental results show that the new model and algorithm are effective for image restoration.


Author(s):  
Liqiong Zhang ◽  
Min Li ◽  
Xiaohua Qiu

To overcome the “staircase effect” while preserving the structural information such as image edges and textures quickly and effectively, we propose a compensating total variation image denoising model combining L1 and L2 norm. A new compensating regular term is designed, which can perform anisotropic and isotropic diffusion in image denoising, thus making up for insufficient diffusion in the total variation model. The algorithm first uses local standard deviation to distinguish neighborhood types. Then, the anisotropic diffusion based on L1 norm plays the role of edge protection in the strong edge region. The anisotropic and the isotropic diffusion simultaneously exist in the smooth region, so that the weak textures can be protected while overcoming the “staircase effect” effectively. The simulation experiments show that this method can effectively improve the peak signal-to-noise ratio and obtain the higher structural similarity index and the shorter running time.


1993 ◽  
Vol 23 (7) ◽  
pp. 1245-1251 ◽  
Author(s):  
D. Andrew White

Correlations and functional relationships of sapwood and annual ring cross-sectional areas versus the number of leaves supported inside the live crowns of red oak (Quercusrubra L.) were found, based on analyses of six 20- to 25-year-old oaks from monocultures in southern Ontario. Differences in numbers of leaves supported across intervals inside the crowns were compared, using correlation analyses, with the corresponding differences in conductive sapwood (outer two annual rings) cross-sectional areas, and the current and previous year's annual ring's cross-sectional areas. These analyses showed that the current year's annual ring area had a lower correlation with number of current leaves supported (R = 0.918, P < 0.0001) than did the previous year's annual ring area (R = 0.953, P < 0.0001) or the conductive sapwood area (R = 0.939, P < 0.0001). Functional relationships between foliar numbers supported and sapwood and annual ring cross-sectional areas inside the live crowns were found with regression analysis. The previous year's ring area (PRA) had a more linear relationship to leaf counts (FQ) than did conductive sapwood area and current annual ring area. FQ = 815.6 leaves/cm2 × PRA1.14 − 137.9. The close relationship between current foliage and previous annual ring area may reflect a developmental link between foliar primordia, which will become the following year's foliage, and the cross-sectional area of the supporting xylem.


Author(s):  
G. R. Forster

A tagging investigation on the ormer (Haliotis tuberculata L.) has been carried out for the Guernsey States Sea Fisheries Committee. Cementing plastic discs to the shell has proved a satisfactory technique since substantial numbers of 40—50% were recovered after 1 and 2 years in the open sea off the west coast of Guernsey. From the increase in shell size of the recovered specimens the mean growth rate has been shown to be about 15 mm of shell length per year up to a shell size of 50 mm, and thereafter decreasing until at 100 mm length growth is negligible. The growth parameters K and L∞ have been calculated. Annual rings were frequently, though not invariably, found on the shell. From the frequencies of the shell-ring lengths in the smaller ormers estimates of the shell size reached 1 and 2 years after settlement have been made. A single annual ring was also found with the majority of the larger shells (> 50 mm), though when growth did not exceed 4 mm in a year the rings were not included owing to the difficulty of separating annual rings from possible disturbance rings caused by the process of tagging. The position of the annual ring varied, being closer to the outer edge of the shell with increasing size. Measurements of the length increase from one annual ring to the next indicated rates of growth closely comparable to those obtained from tagging measurements. Damage to the shells by the boring sponge Cliona lobata Hancock is very widespread, particularly in the larger ormers living below the tide marks.


2019 ◽  
Author(s):  
Michal Chapal ◽  
Sefi Mintzer ◽  
Sagie Brodsky ◽  
Miri Carmi ◽  
Naama Barkai

AbstractGene duplication promotes adaptive evolution in two principle ways: allowing one duplicate to evolve a new function and resolving adaptive conflicts by splitting ancestral functions between the duplicates. In an apparent departure from both scenarios, low-expressing transcription factor (TF) duplicates commonly regulate similar sets of genes and act in overlapping conditions. To examine for possible benefits of such apparently redundant duplicates, we examined the budding yeast duplicated stress regulators Msn2 and Msn4. We show that Msn2,4 indeed function as one unit, inducing the same set of target genes in overlapping conditions, yet this two-factor composition allows its expression to be both environmental-responsive and with low-noise, thereby resolving an adaptive conflict that inherently limits expression of single genes. Our study exemplified a new model for evolution by gene duplication whereby duplicates provide adaptive benefit through cooperation, rather than functional divergence: attaining two-factor dynamics with beneficial properties that cannot be achieved by a single gene.


1942 ◽  
Vol 20c (1) ◽  
pp. 28-40 ◽  
Author(s):  
L. P. V. Johnson

Experiments were conducted on the relation of growth rate to wood quality in a series of 43 hybrid and parental trees, which involved Populus alba, P. grandidentata, and P. tremuloides.Fibres in fast growth annual rings were longer on the average than those in slow growth rings from the same tree. In single annual rings, fibres of early wood were shorter and thicker than those of late wood.Average fibre diameter of individual trees was significantly correlated in a positive manner with growth rate, but the correlation between fibre length and growth rate was well below the level of significance.Short, thick habit of growth was significantly correlated with high density of wood, but correlations between growth rate (in terms of annual increment in volume) and wood density were insignificant.Experimental pulp and paper tests did not reveal any very striking differences in quality between fast growing hybrid and slow growing parental trees, although there remains some doubt as to the suitability of abnormally fast growth hybrid wood for some of the higher grades of soda pulp paper.The general, and tentative, conclusion is that the investigation revealed nothing to indicate that rapid growth is seriously detrimental to wood quality.


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