An Optimum Design Concept for Offshore Cage Culture

2012 ◽  
Author(s):  
Mohamed Shainee ◽  
Bernt J. Leira ◽  
Harald Ellingsen ◽  
Arne Fredheim
Keyword(s):  
Optimum Design ◽  
Single Point ◽  
Growth Conditions ◽  
Design Concept ◽  
Vertical Force ◽  
Horizontal Force ◽  
Offshore Aquaculture ◽  
The Waves ◽  
Scale Of Operation

There is an overwhelming support to move aquaculture cages into offshore waters. Some of the key drivers for moving into offshore waters are limitation of available space near the coast, conflicts within as well as other coastal users, prospect of limitless expansion in offshore sites, the potential for optimum growth conditions and the need to reduce the production cost by increasing the scale of operation. Therefore, by using a set of requirements derived earlier by the authors, the paper looks into the current offshore cage designing concepts in order to propose an optimum design concept for offshore aquaculture. With the help of an expert panel, representing various disciplines which are important for fish farm development, the assessment point towards a single point mooring cage concept as the best option for offshore aquaculture farming. This concept is demonstrated by the use of simple geometric relations and graphs, showing the relation between the total horizontal forces, FH, vertical force component, FV, as the cage submerge. While the contribution from the current, FHC, to the total horizontal force, FH, is kept constant, the contribution from the waves to the total horizontal force, FH, (as assumed to be 33%) is subjected to a reduction proportional to the factor e2kz, representing the reduction in water particle velocity as a function of depth. Further, in light of the requirements derived through the major stakeholders, this paper also propose an alternative classification of cages into two major categories, i.e. systems that are intended to resist and dissipate environmental forces and system that are designed to avoid environmental forces.

Fore-Aft Forces in Tire-Wheel Assemblies Generated by Unbalances and the Influence of Balancing

1991 ◽  
Vol 19 (3) ◽  
pp. 142-162 ◽  
Author(s):  
D. S. Stutts ◽  
W. Soedel ◽  
S. K. Jha
Keyword(s):  
Mathematical Model ◽  
Elastic Foundation ◽  
Torsional Oscillation ◽  
Vertical Direction ◽  
Torsional Stiffness ◽  
Rolling Motion ◽  
Vertical Force ◽  
Horizontal Force ◽  
Wheel Rim ◽  
Open Question

Abstract When measuring bearing forces of the tire-wheel assembly during drum tests, it was found that beyond certain speeds, the horizontal force variations or so-called fore-aft forces were larger than the force variations in the vertical direction. The explanation of this phenomenon is still somewhat an open question. One of the hypothetical models argues in favor of torsional oscillations caused by a changing rolling radius. But it appears that there is a simpler answer. In this paper, a mathematical model of a tire consisting of a rigid tread ring connected to a freely rotating wheel or hub through an elastic foundation which has radial and torsional stiffness was developed. This model shows that an unbalanced mass on the tread ring will cause an oscillatory rolling motion of the tread ring on the drum which is superimposed on the nominal rolling. This will indeed result in larger fore-aft than vertical force variations beyond certain speeds, which are a function of run-out. The rolling motion is in a certain sense a torsional oscillation, but postulation of a changing rolling radius is not necessary for its creation. The model also shows the limitation on balancing the tire-wheel assembly at the wheel rim if the unbalance occurs at the tread band.

scholarly journals Report of the Kew Committee for the fourteen months ending December 31, 1891

1892 ◽  
Vol 51 (308-314) ◽  
pp. 152-182
Keyword(s):  
Vertical Force ◽  
Horizontal Force ◽  
Increased Activity

The operations of The Kew Observatory, in the Old Deer Park, Richmond, Surrey, are controlled by the Kew Committee, which is constituted as follows: The magnetographs have worked satisfactorily all through since last report. The curves obtained, representing Declination, Horizontal Force, and Vertical Force, have shown a marked increased activity in terrestrial magnetic changes as compared with the preceding year, although no very large disturbances have been registered.

scholarly journals Graffiti as a sign: the semiotic approach to the study of the phenomenon

2019 ◽  
Vol 9 (18) ◽  
pp. 92-98
Author(s):  
Maria Chikarkova ◽  
Keyword(s):  
Cultural Context ◽  
Single Point ◽  
Point Of View ◽  
Urban Life ◽  
Street Art ◽  
The Media ◽  
Cultural Code ◽  
The One ◽  
Different Characteristics

Although graffiti is a well-known phenomenon of street art, there is still no single point of view on this phenomenon (even if it is considered art at all). Both the essence and the manifestations of graffiti remain a matter of debate - there are dozens of different classifications, that they are based on different characteristics. However, the phenomenon has rarely attracted attention from the point of view of semiotics, though it is the semiotic reading of graffiti that makes it possible to understand its nature more deeply. Due to semiotics we could create an integrative classification, which would combine stylistics and subject matter into one system. The article made exactly such an attempt –providing of the semiotic classification of graffiti, based on Ch. Peirce’s classification of semiotic signs. Graffiti is a sign, because it has a material shell of the latter, a marked object and rules of interpretation. It functions within the subculture and signifies the individual's desire to escape from the deterministic nature of urban life (J. Baudrillard). It is a culture of the semiosphere, which continuously gives rise to new connotations and, accordingly, generates new receptions. An important component of graffiti interpretation is the cultural code; it is not read outside the field of conventionality, cultural context. Decoding of graffiti can occur in three ways. From our point of view, it is appropriate to use S. Hall’sclassification. He suggested a scheme for "decrypting" messages in the media, however, in our opinion, his scheme works for any communicative act (including graffiti). He distinguished dominant ("dominant-hegemonic"), oppositional ("oppositional") and negotiated ("negotiated") decoding. In the graffiti situation, oppositional decoding prevails among ordinary recipients (passers-by). U. Eco called this type aberrant, because it provides "decryption" of text with a different code than the one it was created for. Authors of graffiti themselves are often not fully aware of what they createalso. Modern writers use techniques of op-art, Dadaism, surrealism, etc., without being very oriented in all these directions. When graffiti combines different types of art (for example, the combination of painting with literature), it takes into account the features of inter-semiotic translation, which makes the decoding situation even more complicated. We offercreating a semioticclassificationofgraffiti, that might be based on Ch. Peirce’s classification of semiotic signs, whichdistinguishthesigns-copies, signs-indexes, signs-symbols. It could help the essence of graffiti and decode them.

scholarly journals Lipschitz Bounds and Nonautonomous Integrals

2021 ◽  
Author(s):  
Cristiana De Filippis ◽  
Giuseppe Mingione
Keyword(s):  
Variational Problems ◽  
Growth Conditions ◽  
Regularity Criteria ◽  
Regularity Of Solutions ◽  
Optimal Regularity ◽  
Lipschitz Regularity ◽  
Elliptic Case ◽  
Different Types ◽  
Vector Valued

AbstractWe provide a general approach to Lipschitz regularity of solutions for a large class of vector-valued, nonautonomous variational problems exhibiting nonuniform ellipticity. The functionals considered here range from those with unbalanced polynomial growth conditions to those with fast, exponential type growth. The results obtained are sharp with respect to all the data considered and also yield new, optimal regularity criteria in the classical uniformly elliptic case. We give a classification of different types of nonuniform ellipticity, accordingly identifying suitable conditions to get regularity theorems.

scholarly journals A model for variable phytoplankton stoichiometry based on cell protein regulation

2013 ◽  
Vol 10 (2) ◽  
pp. 3241-3279
Author(s):  
J. A. Bonachela ◽  
S. D. Allison ◽  
A. C. Martiny ◽  
S. A. Levin
Keyword(s):  
Physiological State ◽  
Single Point ◽  
Nutrient Content ◽  
Growth Conditions ◽  
Marine Phytoplankton ◽  
Cell Protein ◽  
Nitrogen And Phosphorus ◽  
Elemental Ratios ◽  
Regulatory Processes ◽  
Complex Interactions

Abstract. The elemental ratios of marine phytoplankton emerge from complex interactions between the biotic and abiotic components of the ocean, and reflect the plastic response of individuals to changes in their environment. The stoichiometry of phytoplankton is, thus, dynamic and dependent on the physiological state of the cell. We present a theoretical model for the dynamics of the carbon, nitrogen and phosphorus contents of a phytoplankton population. By representing the regulatory processes controlling nutrient uptake, and focusing on the relation between nutrient content and protein synthesis, our model qualitatively replicates existing experimental observations for nutrient content and ratios. The population described by our model takes up nutrients in proportions that match the input ratios for a broad range of growth conditions. In addition, there are two zones of single-nutrient limitation separated by a wide zone of co-limitation. Within the co-limitation zone, a single point can be identified where nutrients are supplied in an optimal ratio. The existence of a wide co-limitation zone affects the standard picture for species competing for nitrogen and phosphorus, which shows here a much richer pattern. However, additional comprehensive laboratory experiments are needed to test our predictions. Our model contributes to the understanding of the global cycles of oceanic nitrogen and phosphorus, as well as the elemental ratios of these nutrients in phytoplankton populations.

scholarly journals V. Discussion of Kew magnetic data, especially the diurnal inequalities of horizontal force and vertical force, from ordinary days of the eleven years 1890 to 1900

1916 ◽  
Vol 216 (538-548) ◽  
pp. 187-277 ◽  
Keyword(s):  
Diurnal Variation ◽  
Regular Part ◽  
Annual Reports ◽  
Magnetic Data ◽  
Vertical Force ◽  
Horizontal Force ◽  
The Absolute

1. In 1901 the development of electrical traction in West London rendered it clear that unless conditions altered in an unexpected direction, no further magnetic records from Kew Observatory would be sufficiently free from artificial disturbances to be an altogether satisfactory medium for the minute study of phenomena such as the regular diurnal variation. The time seemed to have come for taking stock of the records obtained. The measurement of magnetic curves formed no regular part of the work at Kew Observatory until 1890. Prior to that date the Annual Reports contained only a summary of the results of the absolute observations. Since 1890 the programme of work has included the measurement of the magnetic curves for 5 “quiet" days a month.

scholarly journals Extract from a letter from M. Kämtz addressed to Colonel Sabine (Translation)

1854 ◽  
Vol 6 ◽  
pp. 300-303
Keyword(s):  
Vertical Force ◽  
Horizontal Force ◽  
Terrestrial Magnetism

I have just completed the memoir on terrestrial magnetism which I mentioned to you in former letters. It would follow from the materials which I have employed, that the horizontal force requires constants which differ from those for the vertical force, and the differences, although for the most part not considerable are sometimes too large, as it appears to me, to be overlooked: it is for observers to decide in this matter.

scholarly journals A Single-Point-Fed Wideband Circularly Polarized Rectangular Dielectric Resonator Antenna

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Deqiang Yang ◽  
Meng Zou ◽  
Jin Pan
Keyword(s):  
Dielectric Resonator ◽  
Single Point ◽  
Axial Ratio ◽  
Design Concept ◽  
Impedance Bandwidth ◽  
Dielectric Resonator Antenna ◽  
Circularly Polarized ◽  
Measured Impedance ◽  
Rectangular Dielectric Resonator Antenna ◽  
Good Agreement

A single-point-fed circularly polarized (CP) rectangular dielectric resonator antenna (DRA) with wide CP bandwidth is presented. By usingTE111andTE113modes of the rectangular DRA, a wideband CP performance is achieved. The coupling slot of the antenna contains a resistor loaded monofilar-spiral-slot and four linear slots. Design concept of the proposed antenna is demonstrated by simulations, and parameter studies are carried out. Prototype of the proposed antenna was fabricated and measured. Good agreement between the simulation and measurement is obtained. The measured impedance bandwidth (|S11|<-10 dB) and 3 dB axial-ratio (AR) bandwidth are 51.4% (1.91–3.23 GHz) and 33.0% (2.15–3.00 GHz), respectively.

scholarly journals I. On the diurnal variations of the disturbances of the magnetic declination at Lisbon

1876 ◽  
Vol 24 (164-170) ◽  
pp. 373-375
Keyword(s):  
Diurnal Variations ◽  
Short Paper ◽  
Total Force ◽  
Vertical Force ◽  
Horizontal Force ◽  
Magnetic Declination ◽  
The Subject

The Observatory of Infante D. Luiz has possessed since 1863 a set of magnetographs giving continuous records similar to those at Kew. In 1870 the results of the declination magnetograph, from the year 1864 to 1867, were published; and in 1874 the results for the same period of the bifilar and balance magnetographs (results embracing the horizontal force, vertical force, total force, and inclination) were published. At present the results of the declination for 1868 to 1871 are in course of publication. The subject of this short paper is the diurnal variations of the disturbances of the declination. The method which has been adopted for reducing the disturbances is that of Sir Edward Sabine. I have taken ± 2 millimetres, or 2'·26, as the limits, beyond which limits all readings are regarded as disturbed.

Multivariate Visualiztion and Analysis Tools for Segmentation and Classification of Vibrational Spectroscopic Images

1997 ◽  
Vol 3 (S2) ◽  
pp. 865-866
Author(s):  
F. Delaglio ◽  
L.H. Kidder ◽  
I.W. Levin ◽  
E.N. Lewis
Keyword(s):  
High Resolution ◽  
Vibrational Spectrum ◽  
Point Spectrum ◽  
Dimensional Space ◽  
Single Point ◽  
Full Potential ◽  
Multivariate Approach ◽  
Macroscopic Level ◽  
Chemical And Biological Systems

Vibrational spectroscopic imaging has already demonstrated enormous potential for studying a variety of chemical and biological systems at both the microscopic and macroscopic level. However, these spectral images are large and complicated, typically consisting of tens of thousands of pixels, each with an associated high-resolution vibrational spectrum, leading to data sizes upwards of 64 megabytes. In order to realize the full potential of these spectral images, we must find ways to query the data so that specific questions can be answered.We illustrate a multivariate approach to this challenge, where each pixel is considered to be a single point in a multivariate (N-dimensional) space. The variables (coordinates) of the point in N dimensions are simply the intensities of the N-point spectrum associated with the pixel. In this representation, pixels with similar spectra will tend to cluster together in the multivariate space, since they will have similar coordinates.

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