scholarly journals Determination of Growth and Age of Slow Growing Brittle Stars (Echinodermata: Ophiuroidea) From Natural Growth Bands

1998 ◽  
Vol 78 (3) ◽  
pp. 941-951 ◽  
Author(s):  
Corinna Dahm ◽  
Thomas Brey
Keyword(s):  
Growth Ring ◽  
Natural Growth ◽  
Growth Rings ◽  
Brittle Stars ◽  
Antarctic Species ◽  
Advantages And Disadvantages ◽  
Growth Bands ◽  
Slow Growing ◽  
Size Increment

Growth in ophiuroids is highly variable, and with increasing size and age of an ophiuroid specimen more and more of the innermost growth rings on the vertebral ossicles become overgrown and hence invisible. Two approaches to estimate individual age of slow growing brittle stars using the high Antarctic species Ophionotus victoriae are compared. One method interprets natural growth ring readings as size-increment data, whereas the second method compensates for growth ring overgrowth by means of an iterative corrective approach. Preconditions as well as advantages and disadvantages of both methods are discussed.

Growth Rings in Agathis robusta and Araucaria cunninghamii From Tropical Australia

1983 ◽  
Vol 31 (3) ◽  
pp. 269 ◽  
Author(s):  
J Ash
Keyword(s):  
Growth Rates ◽  
Growth Ring ◽  
Tropical Climate ◽  
Ring Formation ◽  
Vascular Cambium ◽  
Growth Rings ◽  
Radiocarbon Dates ◽  
Tropical Australia ◽  
Araucaria Cunninghamii ◽  
Slow Growing

Agathis robusta and Araucaria cunninghamii trees growing in a seasonal tropical climate in north Queensland produce late wood during cooler and drier periods. Vascular cambium growth rates fluctuate, and slow-growing trees may temporarily have inactive cambium around parts of the trunk so no growth ring is formed. Radiocarbon dates on old Agathis trees indicate that the frequency of ring formation is less than annual.

Experimental Determination of Stiffness Variation Across Growth Rings in Picea abies

Holzforschung ◽  
2001 ◽  
Vol 55 (3) ◽  
pp. 309-317 ◽  
Author(s):  
L.O. Jernkvist ◽  
F. Thuvander
Keyword(s):  
Elastic Moduli ◽  
Abrupt Change ◽  
Growth Ring ◽  
Deformation Behaviour ◽  
Growth Rings ◽  
Digital Speckle Photography ◽  
Conventional Tests ◽  
Stiffness Variation ◽  
Measured Displacement

Summary The radial and tangential deformations in a single growth ring of Norway spruce, which was subjected to moderate tensile loading in its radial direction, were measured by use of digital speckle photography. From the measured displacement field, the transverse coefficients of elasticity ER , ET , GRT and νTR were determined with respect to radial position in the growth ring. As a result of the abrupt change in stiffness from latewood to earlywood in the growth ring, it was possible to establish all four coefficients solely from the radial tension test. The elastic modulus ET was found to be a factor 15 larger in latewood than in earlywood, whereas the corresponding variation for ER was merely a factor 3. The measured variations were in reasonable agreement with predictions from simple two-dimensional honeycomb models of the growth ring cellular structure. The average elastic moduli of the growth ring were found to be twice as large as ER and ET measured in conventional tests on macroscale specimens, whereas the reverse was true for the shear modulus. An explanation to these differences is sought by analysing the loading conditions and deformation behaviour of macroscale specimens used in transverse stiffness testing of wood.

PERTUMBUHAN LINGKARAN POHON JATI PADA DUA SISTEM KULTUR BERBEDA DI JAWA TIMUR

2008 ◽  
Vol 6 (2) ◽  
Author(s):  
Iriwi Louisa S. Sinon
Keyword(s):  
Tree Ring ◽  
Tectona Grandis ◽  
Annual Growth ◽  
Natural Growth ◽  
Growth Rings ◽  
Climate Effect ◽  
Tropical Regions ◽  
Annual Growth Rings ◽  
Chronological Sequence ◽  
Plantation Teak

<p><em>Study dendrochronology or tree-ring dating is defined as the study of chronological sequence of annual growth rings in trees. Teak (Tectona grandis) is one of various tree species that has been identified for the use of tree-ring studies in tropical regions. Teak is found to be suitable for dendrochronology as it is long-lived and develops defined annual growth rings. In Java, teak cans growth naturally or intensively in plantation. The two silviculture conditions will give different sensitivity on climate effect. Therefore, the effect of silviculturer will on natural teak and plantation teak in Saradan, Madiun, and East Java. As a part of the study, ten core samples from natural- growth teak were measured. The samples of growth rings is spanned from 1832 – 2004. Using the COFECHA program, the correlation of the samples (r) was found to be 0.44 point, which is satisfactory to the standard used in dendrochronology. Thus, from this study it can be concluded that natural teak could still be used in dendrochronology, although the sensitivity are not as high as plantation teak. </em></p>

scholarly journals Delay Equivalences in Tuning PID Control for the Double Integrator Plus Dead-Time

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 328
Author(s):  
Mikulas Huba ◽  
Damir Vrancic
Keyword(s):  
Dead Time ◽  
Pid Controllers ◽  
Noisy Environment ◽  
Advantages And Disadvantages ◽  
Implementation Problem ◽  
Low Pass ◽  
Excellent Control ◽  
Low Pass Filters ◽  
Double Integrator

The paper investigates and explains a new simple analytical tuning of proportional-integrative-derivative (PID) controllers. In combination with nth order series binomial low-pass filters, they are to be applied to the double-integrator-plus-dead-time (DIPDT) plant models. With respect to the use of derivatives, it should be understood that the design of appropriate filters is not only an implementation problem. Rather, it is also critical for the resulting performance, robustness and noise attenuation. To simplify controller commissioning, integrated tuning procedures (ITPs) based on three different concepts of filter delay equivalences are presented. For simultaneous determination of controller + filter parameters, the design uses the multiple real dominant poles method. The excellent control loop performance in a noisy environment and the specific advantages and disadvantages of the resulting equivalences are discussed. The results show that none of them is globally optimal. Each of them is advantageous only for certain noise levels and the desired degree of their filtering.

Distribution of juvenile wood in two stems of Larixlaricina

1986 ◽  
Vol 16 (5) ◽  
pp. 1041-1049 ◽  
Author(s):  
K. C. Yang ◽  
C. A. Benson ◽  
J. K. Wong
Keyword(s):  
Juvenile Wood ◽  
Growth Ring ◽  
Ring Width ◽  
Tree Level ◽  
Growth Rings ◽  
Vertical Variation ◽  
Strong Negative Correlation ◽  
Ring Number ◽  
Tracheid Length ◽  
Growth Ring Width

The distribution and vertical variation of juvenile wood was studied in an 81-year-old dominant tree and an 83-year-old suppressed tree of Larixlaricina (Du Roi) K. Koch. Two criteria, growth ring width and tracheid length, were used to demarcate the boundary of juvenile wood. The width of juvenile wood, expressed in centimetres and the number of growth rings, decreased noticeably from the base to the top of the tree. The volume of juvenile wood decreased in a similar pattern. These decreasing trends had a strong negative correlation with the year of formation of cambial initials at a given tree level. The length of these cambial initials decreased with increasing age of formation of the cambial initials. In the juvenile wood zone, there was a positive linear regression between the growth ring number (age) and the tracheid length. The slopes of these regression lines at various tree levels increased as the age of the year of formation of the cambial initials increased. At a given tree level, the length of tracheids increased from the pith to a more uniform length near the bark. However, the number of years needed to attain a more uniform tracheid length decreased from the base to the top of the tree. These relationships suggest that the formation of juvenile wood is related to the year of formation of the cambial initials. Consequently, the juvenile wood is conical in shape, tapering towards the tree top.

Significant choice-of-law interests and its impact on the formation of choice-of-law regulation in the field of intellectual property

2021 ◽  
pp. 186
Author(s):  
Svetlana I. Krupko
Keyword(s):  
Intellectual Property ◽  
Property Rights ◽  
Intellectual Property Rights ◽  
The State ◽  
Close Connection ◽  
Choice Of Law ◽  
Applicable Law ◽  
Advantages And Disadvantages ◽  
Special Rules

This article analyzes the choice-of-law interests of specific and potential participants in the relations of intellectual property rights and the state in order to establish the closest connection of the above type of relation with the state, whose law should be applied. Taking into account the directionality of significant choice-of-law interests, advantages and disadvantages of territorial and universal approaches, a theoretically based solution is proposed for the formation of a general choice-of-law rule on the law to be applied to the relation of intellectual property rights. It was revealed in the study that the diversity of the relations of intellectual property rights (their obligatory and non-obligatory, property and personal non-property nature, other differences in legal features) does not automatically generate a multidirectionality of significant choice-of-law interests that should be taken into account when establishing a close connection of the above type of the relation with the state for determination of applicable law, does not prevent the formation of a general choice-of-law rule for the relations of intellectual property rights in general and does not unequivocally testify in favor of the specialization of its binding. However, the diversity of the relations of intellectual property rights should be examined and evaluated for the feasibility and limits of exceptions from the general choice-of-law rule and the development of special rules for resolving certain private of the relations of intellectual property rights.

scholarly journals HCV Detection, Discrimination, and Genotyping Technologies

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3423 ◽  
Author(s):  
Shrikant Warkad ◽  
Satish Nimse ◽  
Keum-Soo Song ◽  
Taisun Kim
Keyword(s):  
Hepatitis C ◽  
Hcv Infection ◽  
World Health ◽  
Clinical Samples ◽  
Infected People ◽  
Advantages And Disadvantages ◽  
Highly Sensitive ◽  
The World ◽  
Health Organization

According to the World Health Organization (WHO), 71 million people were living with Hepatitis C virus (HCV) infection worldwide in 2015. Each year, about 399,000 HCV-infected people succumb to cirrhosis, hepatocellular carcinoma, and liver failure. Therefore, screening of HCV infection with simple, rapid, but highly sensitive and specific methods can help to curb the global burden on HCV healthcare. Apart from the determination of viral load/viral clearance, the identification of specific HCV genotype is also critical for successful treatment of hepatitis C. This critical review focuses on the technologies used for the detection, discrimination, and genotyping of HCV in clinical samples. This article also focuses on advantages and disadvantages of the reported methods used for HCV detection, quantification, and genotyping.

Application of Electron Backscatter Diffraction for Crystallographic Characterization of Tin Whiskers

2012 ◽  
Vol 18 (4) ◽  
pp. 876-884 ◽  
Author(s):  
Joseph R. Michael ◽  
Bonnie B. McKenzie ◽  
Donald F. Susan
Keyword(s):  
Electron Backscatter Diffraction ◽  
Growth Direction ◽  
Tin Whiskers ◽  
Physical Growth ◽  
Final Choice ◽  
Advantages And Disadvantages ◽  
Electron Backscatter ◽  
Backscatter Diffraction

AbstractUnderstanding the growth of whiskers or high aspect ratio features on substrates can be aided when the crystallography of the feature is known. This study has evaluated three methods that utilize electron backscatter diffraction (EBSD) for the determination of the crystallographic growth direction of an individual whisker. EBSD has traditionally been a technique applied to planar, polished samples, and thus the use of EBSD for out-of-surface features is somewhat more difficult and requires additional steps. One of the methods requires the whiskers to be removed from the substrate resulting in the loss of valuable physical growth relationships between the whisker and the substrate. The other two techniques do not suffer this disadvantage and provide the physical growth information as well as the crystallographic growth directions. The final choice of method depends on the information required. The accuracy and the advantages and disadvantages of each method are discussed.

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