• 항공우주기술
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• 제9권1호
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• pp.143-150
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• 2010

본 연구는 다양한 찬물 온도에 손가락을 침수시켰을 경우 추위유발성혈관확장(Cold-induced vasodilation)이 어떻게 나타나며, 이 반응이 재발현되는지 평가하는데 목적을 두었다. 이를 위해 10명의 건강한 대학생($21.4{\pm}2.5$ yrs, $175.8{\pm}4.1$ cm, $69.6{\pm}7.6$ kg, $11.2{\pm}3.7$ %fat)이 두 번의 실험에 참가하였다. 첫 번째 실험은 상온환경에서 다섯 번의 실험과정 반복으로 이루어졌다. 실험과정은 $43^{\circ}C$의 물에 오른손 가운데 손가락을 5분 동안 담갔다가, 그 후 25분 동안 상온에서 휴식을 가지고, 그 다음 무작위로 물 온도 5, 8, 11, 14, 또는 $17^{\circ}C$ 중 하나에 손가락을 담갔다. 한 과정이 끝나면 다른 수온에서 같은 방식으로 실험이 진행되었다. 재발현 반응을 평가하기 위해 첫 실험 후 최소 5일 후에 같은 방법으로 두 번째 실험이 진행되었다. 실험 중 심박수, 직장온도, 손톱주위온도가 매 6초마다 측정되었다. 결론적으로 재현성에는 최대손가락온도(Tfmax)와 Tfmax-물온도(Tw)에서 재생산 반응을 보였다. 추위자극에 따른 CIVD의 반응은 추위자극이 높을수록 최소손가락온도(Tfmin)와 Tfmax의 반응은 높게 나타났으며, 추위자극이 낮을수록 Tfdiff의 반응은 증가되었다. 그러나 모든 반응시간에는 유의한 차이는 보이지 않았다.

• 한국환경보건학회지
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• 제38권3호
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• pp.261-268
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• 2012

Objectives: The photocatalytic degradation of toluene in a batch mode photoreactor for the purpose of the hazardous waste treatment was investigated. Methods: Kinetic experiments using a low pressure mercury lamp (Lambda Scientific Pty Ltd, 50 Watt) emitting both UV and visible light were performed at $31^{\circ}C$ over toluene concentrations ranging from 10 to 50 mg/l in water with $50%TiO_2/6%WO_3$ (TW) concentration of 1 g/l at a pH of 6. Results: Kinetic studies showed that $50%TiO_2/6%WO_3$ (TW) photocatalyst was highly active in toluene degradation; we observed that 99% of the pollutant was degraded after six hours under visible irradiation; furthermore, we observed that adsorption onto TW catalyst was responsible for the decrease of toluene with pseudo-first order kinetics. It was also found that oxygen as a radical source in the sol medium played a significant role in affecting the photodegradation of toluene, especially with a two-fold elevation. This increase was achieved by a more than four-fold elevation of the photodegradation of toluene in the presence of acetone than without, presumably via an energy transfer mechanism. Conclusions: We concluded that photodegradation in acetone and oxygen molecules along with TW was an effective method for the removal of toluene from wastewater.

• 한국패류학회지
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• 제30권1호
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• pp.87-93
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• 2014

우리나라에 분포하고 있는 둥근전복속에 속하는 북방전복, 둥근전복, 말전복 및 왕전복의 형태적 비교를 하였다. 2013년과 12월부터 2014년 1월까지 경남 삼천포에서 채집한 북방전복 69개체, 제주도 연안에 서 채집한 둥근전복 180개체, 말전복 72개체, 왕전복 54개체를 대상으로 형태비교를 한 결과, 품종별로 각장에 대한 각폭, 각고, 전중량의 상대성장식은 북방전복은 SB = 0.6346SL + 3.9082 ($R^2$ = 0.8956), SH = 0.2399SL + 3.2609 ($R^2$ = 0.8024), $TW=0.0009SL^{2.5622}$ ($R^2$ = 0.8088) 이었고 둥근전복은 SB = 0.7249SL + 1.8035 ($R^2$ = 0.9634), SH = 0.3115SL - 11.223 ($R^2$ = 0.8593), $TW=0.0001SL^{2.9696}$ ($R^2$ = 0.8956) 이었고 말전복은 SB = 0.7730SL - 1.1931 ($R^2$ = 0.933), SH = 0.2082SL + 3.2627 ($R^2$ = 0.6927), $TW=0.0002SL^{2.8330}$ ($R^2$ = 0.8431) 이었고 왕전복은 SB = 0.7513SL - 1.0951 ($R^2$ = 0.913), SH = 0.2618SL - 6.1538 ($R^2$ = 0.6927), $TW=0.0001SL^{2.9614}$ ($R^2$ = 0.9353) 로 나타났다.

• 한국양식학회지
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• 제11권1호
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• pp.105-111
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• 1998

코끼리조개의 서식생태를 알기 위하여 강원도 양양군 인구연안의 코끼리조개 서식장에서 서식 환경 및 생태학적인 시험을 실시하였다. 코끼리조개 서식지의 저층수온 연변화 5.6~$17.5^{\circ}C.$. 였으며, 염분은 32.27~34.22${\textperthousand}$로 연중 안정된 분포를 보였으며, 용존산소는 5.15~7.27 ml/l 범위였다. 서식 저질은 3.0~4.0 의 미세사질이 49.20%, 2.0~3.0 의 세사질이 31.87%로 미세사질과 세사질의 입자가 대부분을 차지하였다. 강원연안에서 채집 조사된 코끼리조개의 각장 조성은 70~135 mm(평균 107.70 mm), 중량 조성은 50~550 g(평균 299.63 g)이였다. 각장 (SL)과 전중량(TW)의 관계는 TW=$1.4446{\times}10^{-3}SL^{2.6067}$의 지수곡선식으로 나타났다.

• 한국패류학회지
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• 제30권1호
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• pp.33-40
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• 2014

본 조사는 2006년 2월부터 2007년 1월까지 12개월에 걸쳐 북한 원산 연안에서 형망에 의해 어획되어 주문진 검역소로 수입되어지는 대복을 실험에 사용하였다. 총 표본수는 3,899개체였고, 비만도를 통하여 추정한 대복의 산란기는 7-8월이며, 주산란기는 8월로 조사되었다. 대복의 패각에 나타난 윤문은 연 1회 형성되는 주기성 윤문으로, 주 윤문형성시기는 7월로 조사되어, 산란 후 초륜이 형성되기까지의 기간은 약 11개월 (0.92년) 로 나타났다. 대복의 상대성장식은 다음과 같다. SH = 0.7405 SL + 0.2227 ($R^2$ = 0.9671) SW = 0.3657 SL + 0.4253 ($R^2$ = 0.922) $$TW=0.4274{\times}10^{-3}{\times}SL^{2.7876}$$ ($R^2$ = 0.9591) 대복의 von Bertalanffy 성장식은 다음 식을 통해 나타낼 수 있었다. $$SL_t=70.80(1-e^{-0.217(t+0.367)})$$ $$TW_t=(1-e^{-0.217(t+0.367)})^{2.7876}$$

• 환경위생공학
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• 제9권2호
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• pp.50-57
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• 1994

Densities of total and injured coliforms in treated water( TW ) and three tap water salt pies( Taps Kl, K2 and K3) of Ku- eui water treatment plant and one tap water sample( Tap T) of Tuk- do water treatment plant were measured 23 times from 1991 to 1992. Coliform regrowth in the water distribution system occurred three times during the study period. When the regrowth episode occurred, injured coliforms were always but total coliforms were not always detected in treated water. Mean densities of total coliforms in TW, and Taps Kl, K2, K3 and T were 0.8, 2.3, 1.9, 1.4 and 2.1 cfu/100mℓ by membrane filtration method using m- TF agar and those of injured coliforms were 3.4, 2.8, 2.5, 2.7 and 2.9 c1u/100mℓ using mondo- LES agar. The injury rates of TW and Taps Kl, K2, K3 and T were 89.5,77.4,67.9, 82.8 and 75.9%, respectively. The high injury rate of coliform bacteria in Seoul water supply can cause regrowth problems in distribution systems due to the repair of injured cells under an appropriate condition. It is recommended the injured coliforms should be measured in drinking water since they can lead to a significant underestimation of total coliforms and result in an inaccurate evaluation of the potential health risks.

• Fisheries and Aquatic Sciences
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• 제27권6호
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• pp.356-365
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• 2024

The study was conducted in the Terie River between January and April 2022. The objectives of the study were to assess the fish species composition, determine the length-weight relationship and condition factor and assess the water quality of the river using international water quality guideline for aquatic life. Gillnets with different mesh sizes, 4, 6, 8 and 10 cm were used to collect fish specimens in both dry and wet seasons. Immediately after capture, the total length (TL) and total weight (TW) of each individual were measured in centimeters and grams, respectively, and their relationship was determined using the power function. The physicochemical water quality parameters were analyzed using standard procedures and wagtech portable water quality Kits and Secchi Disk apparatus. A total of 667 fish specimens were collected from the Terie River, 410 and 257 in dry and wet seasons respectively. A total of six fish species, Oreochromis niloticus, Labeobarbus intermedius, Labeobarbus nedgia, Labeobarbus beso, Clarias gariepinus, and Ramius loti were recorded. For length-weight relationship and condition factor analysis, more abundant fish species (O. niloticus and L. intermedius) which were found in both seasons were selected. The length and weight relationship of L. intermedius were TW = 0.0073TL^3.04 in dry and TW = 0.0337TL^2.59 in we season indicated isometric and negative allometric growth respectively. While O. niloticus showed negative allometric growth, TW = 0.096TL^2.44 and TW = 0.0335 TL^2.76 in dry and wet seasons, respectively. The mean Fulton condition factor (FCF) of L. intermidus were 0.85 ± 0.03 and 0.94 ± 0.25 in dry and wet seasons, respectively. The FCF of O. niloticus was 1.70 ± 0.13 and 1.73 ± 0.12 in dry and wet seasons respectively. Except for ammonia, the physicochemical water quality parameters were with the permissible limit for aquatic life and are suitable for fishes Terie River. The river has commercially important fish specimens that could be used for food security and livelihood improvement. However, there is very limited fishing activity in the river due to less awareness on the value of fishes. Therefore, sustainable fishery development should be done in the river.

• Fisheries and Aquatic Sciences
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• 제26권3호
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• pp.169-180
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• 2023

Oreochromis niloticus is the most ecologically and economically important fish in tropical and sub-tropical aquatic systems. Recently, due to sever anthropogenic stressors, hydrological variations and infestations of invasive alien species in Ethiopian water bodies, fish community structure and ecosystem of Lake Tana is changing alarmingly. So far, there is paucity of information on the morphometric relations and diet composition of O. niloticus in Lake Tana, gulf of Gorgora. A total of 309 fish samples were collected and their total length (TL), standard length (SL) and total weight (TW) were measured to determine morphometric relations; and gut contents were examined to identify most important food item in the diet of the fish. Results indicated that, the relation between TL and SL was significant (p < 0.001) and linear (SL = 0.942TL-2.41) while the relation between TL and TW was curvilinear (TW = 0.014 TL^2.8) indicating allometric growth. Among the total guts scrutinized, 53 (17.3%) of them were empty and the remaining 256 (82.7%) were non-empty. Phytoplankton constituted the largest bulk and occurred in 77% of the guts examined and volumetrically accounted 44.3%. Detritus and zooplankton had an intermediate importance by occurring 60.2% and 63.3% of all guts scrutinized and constituted about 25.6% and 15.5% of the total volume respectively. Contributions of macrophytes, insects, nematodes and unidentified food items were relatively low in their importance. Ontogenetic dietary shift was observed in the diet indicating an omnivorous feeding habit of the adult fish.

• 한국해양학회지:바다
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• 제11권4호
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• pp.152-157
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• 2006

2004년 4월부터 2005년 3월까지 전라북도 김제시 심포면 갯벌에 서식하는 백합의 연령과 성장을 조사하였다. 백합의 패각에 나타나는 윤문은 년 1회 형성되며, 주된 윤문 형성시기는 2월$\sim$4월임을 확인할 수 있었다. 초륜의 형성기간은 약 6개월(0.5년)로 나타났으며, 각장(SL)과 각고(SH)간의 관계는 SH=0.8103 SL + 0.5145$(R^2=0.991)$이고, 각장과 각폭(SW)간의 관계는 SW=0.4897 SL + 0.0315 $(R^2=0.976)$이며, 각장과 전중량(TW)간의 관계는 $TW=2.9195\times10^{-4}\;SL^{2.9547}\;(R^2=0.991)$로 나타났다. 연령 (t)에 대한 각장(SL)의 Bertalanffy 성장식은 $SL_t=104.9(l-e^{-0.2235(t+0.7677)})$였으며, 전중량(TW)의 Bertalanffy 성장식은 $TW_t=280.8(l-e^{-0.2235(t+0.7677)})^{2.9547}$로 추정되었다.

• 한국패류학회지
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• 제17권2호
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• pp.71-78
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• 2001

1995년 4월부터 1996년 3월까지 충청남도 보령시 연안에 서식하는 키조개를 총 701마리 채집하여 성장을 조사하였다. 1. 키조개의 패각에 나타나는 윤문은 년1회 형성되며 주 윤문형성시기는 6월에서 7월로 조사되었다. 2. 초륜 형성기간은 12개월(만 1년)로 나타났다. 3. 각고 (SH)와 총중량 (TW)간의 관계는 TW=5.906$\times$$10^{-3}$S $H^{3.3844}$이었으며, 각장 (SL)과 각고(SH)간의 관계는SL=0.5277SH+0.0934이고, 각장 (SL)과 각폭(SW)간의 관계는 SW=0.2681SH-1.3757였다. 4. 연령(t)에 대한 각고 (SH)와 총중량 (TW)의 Bertalanffy 성장식은 SHt=30.99(1-e-$^{0.321}$2(t+0.9653)/이고 (Fig.11) TWt=657.94(1-e-$^{0.321}$2(t+0.9653/)$^{3.3844}$(Fig. 12)였다.)였다.