• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.109-110
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• 2021

An attempt has been made on a constructive approach to evaluate the performance of snail shell ash (SSA) for its corrosion performance under marine environments. Corrosion performance of steel rebar in chloride contaminated SSA with (0% to 50%) replacement levels of cement extract medium was examined through electrochemical and weight loss techniques. Initially, snail shell powder (SSP) is made by pulverizing and subsequently SSA is by thermal decomposition methods. A critical level of 20 % SSA improved both corrosion resistance properties of cement extracts. SSA is a suitable replacement material for natural limestone in cement productions.

• 한국패류학회지
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• 제26권4호
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• pp.275-283
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• 2010

Many freshwater snail taxa are difficult to identify using morphological traits due to phenotypic plasticity. However, using of molecular DNA marker in combination with morphological traits can provide a reliable means for discriminating among freshwater snail taxa including cryptic species. To discriminate among Korean freshwater snail taxa and resolve their systematic relationships, wesequenced a fragment of mtDNA cytochrome oxidase I (COI) gene from 82 specimens collected from ten different sites distributed along the Korean peninsula. We identified more than seven freshwater snail taxa including cryptic species in Korea. Whereas traditional shell morphology of freshwater snails offers only weak discriminatory power for recognizing 'good' taxa, DNA sequence data provided positive and reliable identification. In addition, a major Semisulcospira clade was clearly separated from the remaining lineages observed including cryptic species. However, a phylogenetic tree inferred from the COI gene data did not fully resolve systematic relationships among pleurocerid taxa in Korea. Establishing more robust shell characteristics for identifying taxa unambiguously and hence improving traditional key shell morphology characters for freshwater snail species is an urgent requirement and will require more rigorous examination of all nominal taxa. While molecular data generated here will be useful for species identification and for describing the systematic relationships among Korean freshwater snails, further analysis will be required.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.175-178
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• 2010

Slow movement of snail can be a benefit since it means less speed of tracking is required to get accurate movement track, but in the other side it is difficult to extract the object because the snail is almost as static as the background. In this paper, we present a technique to track the snail by using one of its common characteristic, dark color of its shell. The technique needs to be robust to illumination change since the experiment is usually to observe the movement of snail both at bright and dim condition. Snail position coordinate in 3D space is calculated using orthogonal stereo vision which combines the information from two images taken from cameras at the top and in front of the aquarium. Experimental results show this technique does not need prior background image extraction and robust to gradual or sudden illumination change.

• 한국식품저장유통학회지
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• 제13권6호
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• pp.749-753
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• 2006

우렁이 생체에 대하여 일반성분을 분석한 결과 수분함량은 74.8%, 조단백질 12.7% 및 조지방 0.6%의 함량을 보여 고단백 저지방의 식품재료로써 그 이용 가능성을 찾을 수 있었다. 또한 우렁이를 껍질, 내장 및 근육 3부분으로 분류하여 무기성분을 분석한 결과 우렁이에 함유되어 있는 주요 무기성분으로는 P, Ca, Mg 및 Na이었으며, 그 중 껍질 및 내장, 근육모두에서는 Ca이 가장 많이 함유되어 있어 중요한 Ca 급원으로 이용 가능하다. 우렁이 생체의 아미노산을 분석한 결과 arginine이 31.7% 로 가장 높게 나타났으며, 다음으로 alanine 21.2%, 와 glutamic acid 7.1% 순이었다. 아미노산의 경우 식용할 수 있는 근육에서 조개의 감칠맛과 풍미성분인 alanine 과 glutamic acid 조성이 많으므로 가공식품제조에 바람직하였으며, 또한 arginine 역시 매우 풍부 해 건강식품으로도 이용 가능성을 보여 주었다. 지방산의 경우 포화지방산이 생체, 내장에서 각각 5.4,2.8%로 나타났다. 이러한 결과는 우렁이의 이용성 제고 및 가공 제품화에 중요한 기초 자료로 활용될 수 있을 것으로 생각된다.

• 한국패류학회지
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• 제27권3호
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• pp.191-192
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• 2011

Pulmonate snail, Onchidium hongkongensis from muddy flat of Muan-gun was recorded as new to the Korean molluscan fauna. Shell-less body light-gray or reddish-gray in colour, oval shaped with numerous pustules on dorsal surface usually covered with mud. Black pair of tentacles with terminal eyes. Including the new record in this study, the family Onchidiidae 2 genera and 2 species in the Korean waters.

• 대한수의학회지
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• 제33권2호
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• pp.277-283
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• 1993

In the present study, observations were made on the life-history of Lymnaea viridis under laboratory conditions, involving incubation period of the eggs and their hatching rate, shell length of the newly hatched snails, sexual maturity, size of the snails when the snail produced the first egg-mass, the number of eggs in each egg-mass, egg-laying, ovipostion, growth rate of the snails, and longevity of the snail. At temperatures between $19.8^{\circ}C$ to $22.5^{\circ}C$, incubation period of the eggs occupied 10~12 days, and after beginning of hatching, all young snails emerged completely from the egg-mass within 5 days. The hatching rate was 88%. The average shell length of the newly hatched snails was about 0.064cm. The rate of growth was extraordinarily rapid under good laboratory conditions. When two snails were reared in one culture vessel($20{\times}15{\times}5cm$) with blue-green algae at about $22^{\circ}C$, snail growth was optimal, taking 37 days to reach 1.2cm in shell length. Sexual maturity reached in about 19 days. The size of the snails at sexual maturity was $0.78{\pm}0.05cm$ in length and $0.47{\pm}0.04cm$ in width. The first egg-masses produced were $0.59{\pm}0.22cm$ in length and $0.34{\pm}0.08cm$ in width, and contained 7~38 eggs. The eggs are usually laid in water. The egg-laying was affected by food and temperature. Snails fed with blue-green algae at about $22^{\circ}C$ produced larger egg-masses than the snails fed with fish food at about $26^{\circ}C$. Under conditions of continuous activity and growth, the maximum expectation of life appears to be 109~350(mean 230) days. And the shell length of snails at death were 1.39~1.64cm.

• 한국응용곤충학회지
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• 제49권4호
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• pp.343-349
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• 2010

왕우렁이는 일본으로부터 식용목적으로 1983년에 국내로 도입되었으나, 현재는 우리나라 벼 담수직파재배지에서 피해가 나타나고 있는 실정이다. 따라서 본 연구는 왕우렁이에 대한 온도 및 벼 생육시기별 섭식량과 피해정도를 구명하여 효율적인 관리대책 수립을 위한 자료로 활용하고자 수행하였다. 온도별($l5{\sim}35^{\circ}C$) 왕우렁이 벼 섭식량은 $30^{\circ}C$에서 가장 많았으며, $30^{\circ}C$에서 왕우렁이 크기별 벼 섭식량은 왕우렁이 유체(각고 15 mm)와 성체(각고 30 mm 이상)는 출아 직후, 1엽, 3엽, 및 5엽의 벼를 1 일 동안각각 19.0/79.8, 11.0/54.5, 5.5/18.5 및 0.0/2.0개를 섭식하였다. 왕우렁이는 먹이 습성상 벼가 어린 유묘기(5엽 이하)에 피해를 많이 주는 것으로 조사되었다. 벼 생육시기별 왕우렁이 성체(각고 25mm 이상) 접종밀도를 달리하여 피해정도를 조사한 결과 벼 출아 직후에서 10 $m^2$당 왕우렁이 개체수가 10마리 일 때 수량감소가 16%로 피해가 가장 심하였다.

• 한국패류학회지
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• 제25권3호
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• pp.211-212
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• 2009

One Iravadiid shell Iravadia (Fluviocingula) elegantula (A. Adams, 1861), from the brackish waters in Kangwon-do was recorded as new to the Korean molluscan fauna. The shell is typically solid and narrowely ovate-conic. The protoconch is small, planorboid to depressed dome-shaped, typically with a minute first whorl. Including the new records in this study, the family Iravadiidae contained 2 genera and 3 species in the Korean water.

• 한국패류학회지
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• 제28권2호
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• pp.175-185
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• 2012

북한강에 서식하고 있는 참다슬기의 산란생태를 파악하기 위하여 생식소 발달단계에 따른 생식주기, 성비, 군성숙도, 보육낭유생의 월별변화 등 번식생태와 관련된 생물학적 기초 자료를 조사하였다. 각고에 대한 각경, 전중, 육중의 상관계수 ($R^2$) 는 0.7761-0.8719로 비교적 높은 상관관계를 나타내었다. 참다슬기의 암컷 생식소는 청록색, 수컷 생식소는 옅은 황색을 띠고, 암컷은 유생을 기르는 보육낭 (brood pouch) 을 가지고 있었다. 암수성비는 0.17-0.58의 범위로 계절적 불균형이 심하였으며, 여름철 암컷 비율이 높고 겨울철 암컷비율이 낮았다. 생식소의 조직학적 조사 및 비만지수, 생식소지수 조사 결과 봄, 가을에 두 번의 정점을 나타낸 후 급격히 떨어지는 경향을 보여 생식소 발달은 봄, 가을 연 2회 이루어짐을 알 수 있으며, 암컷 보육낭속의 유생수 월별변화도 연중 두 번의 피크를 나타냈었고, 보육낭속의 유생수는 월 평균 286-975범위로, 11월에 연중 가장 적었고 3월과 9월에 각각 975개, 863개로 연중 가장 많은 유생을 보유하였다. 50%가 성숙하는 군성숙체장은 각고 13.95 mm였으며, 각고 15mm 이상은 모든 개체가 성숙하고 보육낭을 형성하였다.

• 한국동물학회지
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• 제5권2호
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• pp.9-12
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• 1962

The present observations on the perforation bored into young bivalve Tapes philippinarum (less than 2 mm in shell length) by boring snails were conducted at Sunjae Island in 1960 and Inchon Harbor inn 1962. 1. Young bivalves of the species which were left with bored in them were found both in Inchon Harbor and Sunjae Island. 2. The location of the holes in the valves of the young bivalve varied widely, while the holes of the adult bivalve were located at relatively definite position in the valves. 3. The author realized that the holes are bored by a species of snails that have radulas, for the inner diameters of the holes were much smaller than the router diameters. 4. The size of the holes in the valves of young bivalve was much smaller than those holes bored in adult valves. The minimum size of the holes was only 7.5microns in diameter. 5. The author considered that the boring snail is Natica severa that is found abundantly in Inchon Harbor and Sunjae Island and that this snail is the only species found in the particular areas and performs the above mentioned behavior. However, the author could not confirm experimentally the snail drilling young bivalve of Tapes philippinarum .