• 한국환경과학회지
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• 제23권2호
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• pp.331-333
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• 2014

We investigated the effects of sea urchin shell powder on 2 volatile fatty acids, acetic and butyric acid, in poultry litter. A total of 60 1-d-old male broiler chicks (Arbor Acres) were allocated to 2 treatments (basal diet and 1% sea urchin shell powder) with 3 replicates of 10 birds each. During the 4-week experimental period, significant differences in acetic acid and butyric acid concentrations were observed between treatments (P < 0.05), except for acetic acid at 1 week. Additions of 1% sea urchin shell powder resulted in lower acetic and butyric acid concentrations compared to the litter of control birds. We conclude that the sea urchin shell powder used in this study might prove beneficial in reducing environmental pollution caused by poultry litter.

• 한국환경과학회지
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• 제23권1호
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• pp.153-156
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• 2014

This study was conducted to evaluate the effects of sea urchin shell powder on nitrogen characteristics in poultry litter by assigning ninety 1-d-old male broiler chicks (Arbor Acres) to one of 3 treatments (control, 1% sea urchin shell powder, and 1% feed additives) in 3 replicates of 10 birds each. For all treatments, the overall dry matter contents were decreased (P < 0.05) as time increased, except for at 1 week. When compared with controls, the dietary sea urchin shell powder and feed additives for 0 and 3 weeks did influence their TN contents, but not for 1, 2 and 4 weeks. The treatments with sea urchin shell powder and feed additives had a significant (P < 0.05) influence on $NH_3$-N in poultry litter compared with controls. However, at 4 weeks, no marked differences were observed in $NH_3$-N contents among treatments. Treatments with 1% sea urchin shell powder might enhance the value of poultry litter as N fertilizer.

• 한국환경과학회지
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• 제27권1호
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• pp.55-58
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• 2018

The purpose of this study was to evaluate the effect of sea urchin shell powder, used in broiler diet, on Esherichia coli and Salmonella in litter produced by the broilers. A total of 120 broiler chickens were fed 1 of 3 treatment diets (10 chickens per pen) in a randomized block design treatments with 4 replications. Sea urchin shell powder was used in the concentrations of 0.5% and 1% in the basal diets; the control diet was constituted of basal diet. During the 3-week feeding trials, none of the treatments significantly affected the E. coli populations in poultry litter at weeks 0 and 1, nor did they affect the and S. enterica populations at weeks 1 and 3. However, dietary sea urchin shell powder addition affected the population of E. coli at weeks 2 and 3, and that of S. entericaat weeks 0 and 2 (P<0.05). It is therefore concluded that the use of dietary sea urchin shell powder (0.5% and 1%) will be beneficial enough to reduce E. coli, rather than S. enterica in poultry litter over short-term periods.

• 한국수산과학회지
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• 제42권6호
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• pp.600-603
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• 2009

Genetic and phenotypic parameter estimates for measurement traits were obtained from pacific oyster Crassostrea gigas at nine months old. For the growth-related traits among nine months old pacific oyster, heritabilities of shell length, shell height, shell width, total weight, body weight and shell weight were estimated as 0.4855, 0.5248, 0.0884, 0.7236, 0.7726 and 0.6957, respectively. Genetic correlations among the growth-related traits of pacific oyster at nines month old, shell length, shell height, shell width, total weight, body weight, shell weight were showing highly positive correlations. Breeding value on growth-related traits of pacific oyster at nine months old were estimated as shell length -7.044-11.870, shell height -11.380-18.370, shell width -1.234-2.831, total weight -8.339-17.140, body weight -1.813-3.507 and shell weight -4.422-8.837. The results show that there is quite substantial additive genetic variance for measurement traits in pacific oyster that can be exploited through selective breeding.

• 한국가금학회지
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• 제27권3호
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• pp.221-226
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• 2000

This experiment was conducted to determine the effect of replacing limestone by sea shell on digestibility, egg strength and thickness, Ca and P of serum and Ca and P of tibia in layer hens. A total 54 brown layers was assigned to the treatments. There were six layers per replicate with three replicate per treatment. Treatments were layer diet with 7.5% limestone as control, 7.0% limestone and 0.5% sea shell in diet(SS0.5) and 6.5% limestone and 1.0% sea shell in diet(SS1.0). Digestibility of DM was significantly difference between SS0.5 and SS1.0(P〈0.05). Digestibilities of Ca and P were not affected by treatments(P〉0.05), however, SS1.0 tended to increase Ca and P digestibility compared to control. Egg thickness and egg strength were no differences among the treatments(P〉0.05). Differences of initial and finial period on Ca of plasma were significantly affected in the a.m. between SS0.5 and SS1.0(P〈0.05). However, there was no difference in Ca of plasma in the p.m. among the treatments and Ca of plasma in control had a tendency to decrease in the p.m. compared to that of treatments(P〉0.05). Ca of tibia was significantly increased by SS1.0 compared to control(P〈0.05). However, there was no difference in P of tibia among the treatments(P〉0.05). Based on these results, dietary supplemental sea shell mat have a role to improve the egg quality of layer hens.

• 한국환경과학회지
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• 제29권10호
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• pp.1011-1014
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• 2020

The purpose of this study was to investigate the egg freshness and eggshell characteristics of old laying hens by adding sea urchin shell powder to the feed of such hens to achieve the objectives continuously pursued by environmental management, such as business profitability and waste resource utilization. A total of 90 Hy-Line Brown layers (66 weeks of age) were randomly divided into 2 treatments with 3 replicates, each of which consisted of 15 older layers, for 4 weeks. These treatments included a control (i.e., 0%) and 2% sea urchin shell powder. The 2% supplementation of sea urchin shell powder increased the Haugh unit (HU) at 2 and 4 weeks and eggshell strength at 4 wks compared to the controls (p<0.05). The HU at 0 weeks, eggshell thickness from 0 through 3 weeks, and eggshell strength at 0 and 2 weeks were not different between treatments (p>0.05). These results suggest that the addition of 2% sea urchin powder to the feed of laying hens improves egg freshness and eggshell strength in old laying hens.

• 한국식품영양과학회지
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• 제22권3호
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• pp.291-299
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• 1993

The lipid components of the gonad of sea urchin Hemicentrotus pulcherrimus, ark shell Scapharca bro-ughtonii and "Gaebul" (Korea name, a worm) Urechis unicinctus were investigated. The total lipid (TL) contents of the sea urchin, the ark shell and the "Gaebul" were 6.10, 0.67 and 0.79%, respectively. The percentages of phospholipid (PL) in TL were higher in the "Gaebul"(72.4%) and ark shell(64.9%) compared to the sea urchin (41.7%). The major lipid classes of PL were phosphatidylcholine and phosphatidylethanolamine, and the former was rich in the sea urchin (56.2%) and the latter in the "Gaebul"(34.4%). In the class of non-polar lipid (NL), the major lipid classes were different from species ; the sea urchin was rich in triglyceride(TG, 89.0%), the ark shell rich in TG (69.2%) and cholesterol (ST 26.8%) and the "Gaebul"rich in ST (70.7%). The prominent fatty acids of the sea urchin were 16 : 0, 14 : 0, 20 : 5n-3, 20 : 4n-6 and 20 : 4n-6 and 20 : 2NMID(non-methylene interupted dien). The percentage of 20 : 4n-6 was the highest of the investigated invertebrates, accounting for 19.8% in PL, but 22 : 6n-3 was not detected in the sea urchin. In case of the ark shell, the prominent fatty acids were 16 : 0, 18 : 0, 20 : 5n-3, 22 : 6n-3 and 22 : 2NMID, especially 22 : 6n-3(9.58%) was richer compared to that of the "Gaebul". The prominent fatty acids of the "Gaebul"were 20 : 5n-3, 16 : 0, 18 : 0 20 : 1n-9, 16 : 1n-7 and 14 : 0. The percentage of 20 : 5n-3 (22.0%) was highest in the PL of the "Gaebul"among the three invertebrates. These differences in the lipid components of all the sample is considered to be due to the different food habits and environmental condition of the invertebrates.

• 한국해양공학회지
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• 제28권5호
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• pp.423-428
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• 2014

Ice loads may be conveniently categorized as local ice loads and global ice loads. Local ice loads are often defined as ice pressures acting on local areas of shell plates and stiffeners. Therefore, local ice loads are defined in all ice class rules. However, directly measuring the local ice pressure using the actual ice class vessel is a very difficult task because appropriate instruments for direct measurement must be installed on the outer hull, and they are easily damaged by direct ice contacts/impacts. This paper focuses on the estimation of the local ice pressure using the data obtained from icebreaking tests in the Arctic sea in 2010 using the Korean icebreaking research vessel (IBRV) ARAON. When she contacted the sea ice, the local deformation of the side shell was measured by the strain gauges attached to the inside of the shell. Simultaneously, the contact area between the side shell and sea ice is investigated by analyzing the distribution of the measured strain data. Finally, the ice pressures for different contact areas are estimated by performing a structural analysis.

• 한국패류학회지
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• 제29권3호
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• pp.217-223
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• 2013

The morphological relations and physiological characteristics of the triploid and diploid oysters (Crassostrea gigas) in Taean area, west coast of Korea, were investigated from May 2012 to April 2013. Mophometric analysis indicated that the triploid oysters have the same shell length to shell height ratio but higher shell depth to shell height ratio than diploids. Consistent with morphological characteristics, triploid oysters showed greater values of fatness, condition index and RNA/DNA ratio during the period of experiment. The DNA concentration in adductor muscle and mantle of triploid were either lower or equal to the nucleic acids of diploid. However, RNA/DNA ratio were significantly higher than diploid. It appears that RNA/DNA ratio could be a useful indicator of health condition of triploid and diploid oysters when taken in correlation with the morphological indices.

• 한국소음진동공학회논문집
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• 제14권5호
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• pp.370-376
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• 2004

The overall aim of this paper is to determine coupling loss factor of welding point between shell and cylinder using loss factor and structural loss factor. For this purpose, two kinds of loss factor were adopted. One is loss factor of each sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it ispossible to derive the coupling loss factor which represent characteristic condition of SEA theory. Coupling loss factor of conjunction in complex structure was expressed as power balance equation. The derived equation for a coupling loss factor has been simplified on the assumption of one way (uni-directional) power flow between multi-sub structures. Using these conditions, it is possible to find the equation of coupling loss factor expressed as above two loss factors. To check the effectiveness of above equation, this paper used two-stage application. The first approach was application between simple cylinder and shell. The next was adopted rotary compressor. Rotary compressor has three main conjunctions between shell and internal vibration part. This equation was applied to find out the optimum welding point with respect to reduce the noise propagation. It shows the effective tool to evaluate the coupling loss factor in complex structure