• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.387-396
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• 2022

In this study, the removal efficiencies of heavy metals were evaluated using cockle, abalone, and scallop shells. Cockle, abalone, and scallop are composed mainly of aragonite, aragonite, and calcite, and calcite, respectively. The specific surface area of each shell varies from 2.7241 m²/g to 4.5481 m²/g and the order of that is scallop > abalone > cockle. All shells of cockle, abalone, and scallop had no As removal effect by adsorption and precipitation as pH increased. Pb was removed by all shell samples at initial reaction. Although the removal efficiency of Cd and Zn were depending on the reaction medium, that was increased in order of scallop > abalone > cockle. Heavy metal removal efficiency tends to be slightly higher for heated samples than with the raw materials, and higher as the specific surface area is larger.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.467-468
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• 2006

• Journal of Korean Society of Steel Construction
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• v.12 no.5 s.48
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• pp.487-494
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• 2000

This paper intends to propose design information with the result or comparing the deformation capacity with different panel stiffness specimens and estimating the plastic deformation capacity, toughness and strength of welded joint connection according to the different scallop types. The test results of the beam to column unit structure are as follow: the non-scalloped and the low stiffness panel specimen have more desirable result values than the scalloped and the high stiffness one in plastic deformation. Comparing the scallop types shows very unlikely tendency as follows, second cracking occurs at the very edge of scallop in the scalloped specimen otherwise cracking occurs bond area of welded beam flange in the non-scalloped one.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.1-6
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• 2001

The genetic relationship was examined with PCR-RAPD markers among three scallop species, Chlamys farreri farreri, Patinopecten yessoensis, and Agropecten irradians. Six primers were selected from 60 primers used to compare PCR-RAPD profiles among species. All primers showed distinct RAPD band patterns between the three species. In Chiamys farreri farreri, the morphological characteristics such as shell size and color were considerably different between the two geographical populations. RAPD profile, however, showed that no significant genetic differences were found between the two geographical populations. Polymorphic alleles were observed within a population of each species. Thus, PCR-RAPD markers are useful in identifying scallop species and in understanding scallop population genetic structure.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1418-1425
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• 2003

In CAD systems, a surface to be machined is expressed by a series of curves, such as B-spline, Bezier and NURBS curves, which compose the surface and then in CAM systems the curves are divided into a large number of line or arc segments. These divided movement commands, however, cause many problems including their excessive size of NC data that makes almost impossible local adjustment or modification of the surface. To cope with those problems, the necessity of real-time curve or surface interpolators was embossed. This paper presents an efficient real-time tool-path generation method fur interpolation of NURBS surfaces in CNC machining. The proposed tool-path generation method is based on an improved iso-scallop strategy and can provide better precision than the existing methods. The proposed method is designed such that tool-path planning is easily managed in real-time. It proposed a new algorithm for regulation of a scallop height, which can efficiently generate tool-paths and can save machining time compared with the existing method. Through computer simulations, the performance of the proposed method is analyzed and compared with the existing method in terms of federate, total machining time and a degree of constraint on the scallop height.

• Journal of fish pathology
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• v.21 no.3
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• pp.167-174
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• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• International Journal of Korean Welding Society
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• v.1 no.1
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• pp.51-57
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• 2001

Effect of the joint details on the stress distribution over a slot structure has been studied in order to improve its fatigue life using a finite element analysis. The joint details of interest are the radius and height of scallop at the stiffener as well as the mis-alignment between the stiffener and longitudinal member. For a slot structure currently used, the stiffener heel is subjected to the maximum stress for a given external load, where is a potential fatigue crack initiation site. The stresses at the stiffener heel and toe decrease both by increasing the scallop radius and more significantly by increasing the mis-alignment while no notable effect of the scallop height on it is appreciated. A proper combination of these factors makes it possible to reduce the stresses at the stiffener heel and In, theoretically, more than 50%. This is attributed to the modification of the stress distribution over the slot structure including the transition of the maximum stressed region from the stiffener heel to the slot surface of the transverse web. Such then results in a g[eat improvement of the fatigue life of the slot structure.

• The Korean Journal of Malacology
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• v.23 no.2
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• pp.173-180
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• 2007

Health state of the Japanese scallop, Mizuhopecten yessoensis, cultured in the Experimental Marine Farm in Minonosok Bay (Peter the Great Bay, Sea of Japan) was investigated. The wide spectrum of histopathological changes has been identified in the internal organs and tissues of scallops: prokaryotic infection with prevalence 100%, destruction of digestive epithelium and other changes in digestive system, infiltration of organs by hemocytes and granulocytome formation. The most affected by prokaryotic infection organs are labial palps, lips, esophagus, intestine and gills. Several of the observed alterations seem to be related to prokaryotic infection.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.778-783
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• 2009

In this research, we propose a method to extract scallop areas in seabed images in order to construct a system that can measure automatically the number, size, and state of fishery resources, especially scallops, by analyzing seabed images. Our algorithm is based on information about the hue, characteristic pattern, and the shape of scallop shells. The effectiveness of the proposed method is illustrated through an experiment.

• Journal of Aquaculture
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• v.15 no.1
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• pp.61-68
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• 2002

A comparative study on the effect of rearing depths at 2 (surface) and 5 (bottom) m on growth of the scallop was undertaken in Nam-myeon coastal area during June to December, 1997. There were very little difference in the levels of temperature (12.2 ~24.5$^{\circ}C$), salinity (27.3 ~33.1$\textperthousand) and dissolved oxygen (>7.05 mg/l) at a given month. But the chlorophyll level fluctuated between 1.2 and 11.0 $\mu g/l$ at the surface but below 2 $\mu g/l$ at the bosom. Highest phytoplankton density occurred in August and Ceratium dominated it during the period from June to October. Mean growth of the bay scallop at surface and bottom for the six months rearing period was as follows; 0.19 and 0.16 mm/day for shell height, and 0.16 and 0.12 g/day for total weight. Maximum predicted values of shell height calculated by von Bertalanffy growth model were 52.62 mm for the surface and 46.73 mm for the bottom reared scallop. Survival of the scallop was higher (80 %) for the surface group than that at the bottom (60%).