• 한국해안해양공학회지
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• 제18권4호
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• pp.372-382
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• 2006

기존 방파제의 대부분은 항내외 흐름을 차단시키는 불투과성 방파제로서 항내의 수질오염을 심화시키고 있다. 이러한 문제점을 해결하기 위해 최근에 여러 형식의 해수교환방파제가 제안되고 있다. 해수 교환 방파제의 형식에는 흐름을 이용한 조류제, 파랑을 이용한 월류제 등이 있다. 이 중에서 파랑에너지에 의한 해수교환 형식은 항내로 월파되는 월파량의 계산시 적절한 유량계수의 산정을 필요로 한다. 본 연구는 적절한 유량계수의 도입을 통해서 정량적인 월파량을 계산하고, 월류식 해수교환방파제의 해수교환 효과를 검토한 것이다. 파량의 계산은 정상상태의 하천에서 월류제를 넘어가는 월류량을 산정하는데 사용되고 있는 Forchheimer의 식을 시간의존 완경사방정식에 적용하여 가능하도록 하였다. 이 때 가장 중요한 매개변수인 유량계수는 수리모형실험으로 추정하였다. 이와 같은 방법을 제주외항 서방파제의 해수교환 구간에 적용하고 해수교환 성능을 검토해 보았다. 평상 파랑 조건이 파고 3.7 m, 주기 8.5 s, NNW방향일 때, 항내로 공급되는 월파량은 $27.5m^3/s$로 산정 되었다.

• Journal of Animal Science and Technology
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• 제59권7호
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• pp.19.1-19.10
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• 2017

Background: To reduce use of main feed ingredient like corn, soy bean meal (SBM) and wheat, alternative ingredients has been studied like copra meal (CM). Production amount of CM which has been high makes CM to be an alternative feed stuff. However, low digestibility on AA and low energy content by high fiber content can be an obstacle for using CM. This experiment was conducted to evaluate the effects of CM supplementation with ${\beta}$-mannanase on growth performance, blood profile, nutrient digestibility, pork quality and economic analysis in growing-finishing pigs. Methods: A total of 100 growing pigs ([Yorkshire ${\times}$ Landrace] ${\times}$ Duroc) averaging $31.22{\pm}2.04kg$ body weight were allotted to 5 different treatments by weight and sex in a randomized complete block (RCB) design in 5 replicate with 4 pigs per pen. Treatments were 1) Control (corn-SBM based diet + 0.1% of ${\beta}$-mannanase (800 IU)), 2) CM10 (10% copra meal + 0.1% ${\beta}$-mannanase (800 IU)), 3) CM15 (15% copra meal + 0.1% ${\beta}$-mannanase (800 IU)), 4) CM20 (20% copra meal + 0.1% ${\beta}$-mannanase (800 IU)) and 5) CM25 (25% copra meal + 0.1% ${\beta}$-mannanase (800 IU)). Four phase feeding program was used: growing I (week 1-3), growing II (week 4-6), finishing I (week 7-9) and finishing II (week 10-12). Results: In growth performance, there was no significant difference among treatments during whole experimental period. In growingI phase, G:F ratio tended to increase when CM was increased (P = 0.05), but ADG and ADFI tended to decrease in finishingII phase (linear, P = 0.08). Also, increasing CM reduced ADG (linear, P = 0.02) and feed efficiency (linear, P = 0.08) during the whole finishing period. In blood profiles, BUN was linearly increased as CM increased (linear, P = 0.02) at growingII period. In digestibility trial, there was no significant difference in dry matter, crude fat, crude ash and nitrogen digestibility. However, crude protein digestibility was decreased linearly (linear, P = 0.02). In economic analysis, feed cost per weight gain and total feed cost per pig were reduced in overall period when CM was provided by 25% (linear, P = 0.02). Conclusion: CM with 0.1% of ${\beta}$-mannanase (800 IU) could be supplemented instead of corn and SBM up to 25% without detrimental effects on growth performance and pork quality of growing-finishing pigs.

• 한국방재학회 논문집
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• 제10권6호
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• pp.59-64
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• 2010

산불 지표화의 방화선 구축작업은 낙엽 및 관목류 등 지표 연료층을 제거함으로써 화염전파를 차단하는 대표적인 간접진화방법이다. 화재역학적인 의미의 방화선 구축은 화염으로부터 방출되는 열전달에너지에 미연소 연료가 착화되지 않도록 열전달 차단 구간을 설정하는 작업이다. 본 연구에서는 소나무 낙엽층에 대해 복사열전달 점열원 모델을 이용하여 풍속, 경사별로 지표화 화염을 방지할 수 있는 방화선 구축 폭 산정 방법을 제시하였고 평가를 실시하였다. 방화선 구축 폭은 소나무 낙엽 착화 임계 복사열유속인 $4.9\;kW/m^2$가 미치는 거리를 기준으로 평가하였다. 그 결과, 풍속 0~5 m/s, 경사 $0{\sim}50^{\circ}$ 조건에서의 방화선 구축 폭은 평균 화염 기준의 경우, 0.35~0.65 m, 최대 화염높이 기준의 경우, 0.75~1.05m로 산정되었다. 따라서 안전율을 고려한 적정 방화선 구축 폭은 최대 화염 높이를 적용한 1.05 m가 적합할 것으로 판단되며 향후, 실험 및 현장사례조사를 통하여 지표층 연료별 적정 방화선 구축 폭에 대한 비교분석 연구가 추가적으로 필요할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1073-1079
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• 2010

Forty-eight ((Duroc${\times}$Yorkshire)${\times}$Landrace) pigs with an average initial body weight (BW) of $48.47{\pm}1.13\;kg$ were used in a 12-week growth trial to investigate the influence of Anion (silicate) supplementation on growth performance, nutrient digestibility, meat quality and fecal noxious gas content in growing-finishing pigs. Pigs were allotted into three dietary treatments in a randomized complete block design according to sex and initial BW. Each dietary treatment consisted of four replications with four pigs per pen. Dietary treatments included: i) CON (basal diet), ii) HCI (basal diet+3 g/kg Anion), iii) HCII (basal diet+6 g/kg Anion). No significant difference (p>0.05) was detected for average daily gain (ADG), average daily feed intake (ADFI) and gain/feed ratio (G/F) throughout the experiment, although dietary supplementation of Anion numerically increased these characteristics compared with CON. The dietary HCI group significantly (p<0.05) increased the coefficient of total tract apparent digestibility (CTTAD) of dry matter (DM), nitrogen (N) and energy compared with the CON group (p<0.05). No significant difference was observed in meat quality except that meat firmness was linearly (p<0.05) increased by the Anion supplementation, while an increased tendency in meat color and a decreased tendency in 2-thiobarbituric acid reactive substances (TBARS) was also observed (p<0.10). Anion supplementation linearly (p<0.05) decreased the fecal $NH_3$ compared with the CON group. However, dietary Anion supplementation at 3 g/kg decreased the $H_2S$ concentration compared with CON, while no significant difference was detected in the HCII group, although the $H_2S$ emission was numerically decreased compared with CON. In conclusion, supplementation of the diet with 3 g/kg Anion was found to exert a beneficial effect on nutrient digestibility and meat quality of growing-finishing pigs, and concomitantly decreased the noxious gas emission without negative effect on growth performance.

• Asian-Australasian Journal of Animal Sciences
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• 제21권2호
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• pp.204-213
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• 2008

Four ruminally cannulated Holstein cows averaging 43 days in milk (DIM) were used in a $4{\times}4$ Latin square to determine the effect of feeding extruded soybean, ground canola seed and whole cottonseed on ruminal fermentation and milk fatty acid profile. One hundred and twenty lactating Holstein cows, 58 (${\pm}31$) DIM, were assigned to four treatments in a completely randomized block design to study the effects of the three types of oilseeds on production parameters and milk fatty acid profile. The four diets were a control diet (CON) and three diets in which 10% extruded soybean (ESB), 5% ground canola seed (GCS) and 10% whole cottonseed (WCS) were included, respectively. Diets consisted of concentrate mix, corn silage and Chinese wild rye and were balanced to similar concentrations of CP, NDF and ADF. Ruminal fermentation results showed that ruminal fermentation parameters, dry matter intake and milk yield were not significantly affected by treatments. However, compared with the control, feeding cows with the three oilseed diets reduced C14:0 and C16:0 and elevated C18:0 and C18:1 concentrations in milk, and feeding ESB increased C18:2 and cis9, trans11 conjugated linoleic acid (CLA). Production results showed that feeding ESB tended to increase actual milk yield (30.85 kg/d vs. 29.29 kg/d) and significantly decreased milk fat percentage (3.53% vs. 4.06%) compared with CON. Milk protein (3.41%) and solid non-fat (13.27%) from cows fed WCS were significantly higher than from cows fed CON (3.24% and 12.63%, respectively). Milk urea N concentrations from cows fed the ESB (164.12 mg/L) and GCS (169.91 mg/L) were higher than cows fed CON (132.31 mg/L). However, intake of DM, 4% fat corrected milk, energy corrected milk, milk fat and protein yields, milk lactose percentage and yield, somatic cell count and body condition score were not affected by different treatments. The proportion of medium-chain fatty acid with 14 to 16 C units in milk was greatly decreased in cows fed ESB, GCS and WCS. Feeding ESB increased the concentration in milk of C18:1, C18:2, C18:3 and cis9, trans11-CLA content by 16.67%, 37.36%, 95.24%, 72.22%, respectively, feeding GCS improved C18:0 and C18:1 by 17.41% and 33.28%, respectively, and feeding WCS increased C18:0 by 31.01% compared with feeding CON. Both ruminal fermentation and production trial results indicated that supplementation of extruded soybean, ground canola seed and whole cottonseed could elevate the desirable poly- and monounsaturated fatty acid and decrease the medium chain fatty acid and saturated fatty acid content of milk fat without negative effects on ruminal fermentation and lactation performance.

• 한국지역지리학회지
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• 제13권1호
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• pp.32-42
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• 2007

제주도 남서부 안덕면의 사계해안에는 미고결 하모리층의 파식대지와 해안단구 퇴적층, 패사 및 화산사로 이루어진 해안사구, 배후호소 등이 상호 유기적으로 연계되어 있다. 본 연구에서 OSL 연대측정법을 이용하여 분석한 사계 해안지형시스템의 형성과정은 다음과 같다. 첫째, 하모리층은 약 7,600$\sim$3,000년 전에 해저 화산분출에 의하여 재 이동된 응회암이 쌓인 수평 지층이다. 하모리층과 광해악현무암의 완사면이 만나는 부분에 형성된 와지는 이후 지반이 융기하여 육상으로 드러나면 배후호소를 이룬다. 둘째, 하모리층이 아직 해수면 아래에 있을 때, 광해악현무암으로 이루어진 남서부의 암석해안에서 부서져 마모된 것이거나 소하천으로 공급된 자갈들이 빠른 유수를 따라 이동하여 퇴적되었다. 셋째, 이후 지반이 융기함으로써 원력의 퇴적은 중단되었으며, 파랑의 전진에너지에 따른 마식작용으로 파식대가 형성되었다. 파식대의 고도는 대조시의 고조위면과 일치하므로, 현재 연구지역의 고조위면과 비교해 보면, 지반은 파식대 형성 이후 약 1.5m 융기하였다. 넷째, 해저로부터 많은 사질 퇴적물이 공급되어 파식대지와 해안단구 역층을 피복하였다. 사질 퇴적물 가운데 보다 가벼운 입자들은 바람에 실려 배후로 이동하여 500년 전부터 전사구나 이차사구를 형성하였다.

• 한국통신학회논문지
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• 제29권5C호
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• pp.706-715
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• 2004

본 논문에서 제안되는 워터마크(Watermark) 삽입 알고리즘은 웨이블릿 변환 영역에서 구성되는 부대역간의 트리구조(Tree structure)와 공간 영역에서의 윤곽선 정보를 이용하여 워터마크를 삽입할 영역을 결정하고 삽입한다. 먼저 생성되는 고주파 성분의 부대역으로부터 저주파 부대역으로 중요 주파수 영역을 예측하게 되는데 웨이블릿 변환영역에서 구성된 트리구조에서 높은 주파수를 가지는 LHI 부대역을 4${\times}$4의 부행렬(Submatrix)로 나누고 행렬에 대한 평균과 이들에 의해 구성되는 블록 행렬(Block matrix)로부터 전체 평균 및 워터마크 삽입에 이용될 임계값을 얻는다. 또한 주파수 영역에서 구해진 에너지 특성에 대한 블록 행렬과 공간 영역에서 얻어진 영상의 윤곽선 정보에 의해 워터마크가 삽입될 위치인 키맵(Keymap)이 구해진다. 구해진 키맵에 따라서 LFSR(Linear feedback shift register)을 이용하여 발생된 무작위 순열(Random sequence)를 웨이블릿 도메인에서 이웃 웨이블릿 계수간의 관계를 이용하여 삽입한다. 최종적으로 역 웨이블릿 변환을 취함으로써 워터마크가 삽입된 영상을 생성한다. 제안된 워터마킹 알고리즘은 JPEG과 같은 압축과 Blurring, Sharpening, 그리고 가우시안(Gaussian) 잡음 등의 공격에 대해서도 기존의 방식에 비해 약 2㏈ 절도 높은 PSNR(Peak signal to noise ratio)를 보이면서 2%에서 8% 정도 높은 NR(Normalized correlation)를 가져서 좋은 특성을 나타냈다.

• 공업화학
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• 제31권3호
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• pp.291-298
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• 2020

본 연구에서는 RF/DC 마그네트론 증착법을 이용하여 실온에서 유리 기판 상에 ZITO/Ag/ZITO 다층막 투명전극을 제조하였다. ZITO/Ag/ZITO (100/8/42 nm)로 이루어진 다층막 구조에 대해, 면저항이 9.4 Ω/㎡이고 550 nm에서 투과도가 83.2%인 투명 전도성 필름이 얻어졌다. ZITO/Ag/ZITO 다층막 필름의 면저항 및 투과도 특성은 적외선(열선)을 효과적으로 차단할 수 있기 때문에 고분자분산액정(polymer-dispersed liquid crystal, PDLC) 기반 스마트 윈도우 적용에 매우 유용함을 알 수 있었으며 이로 인해 에너지 절약형 스마트 유리로서의 응용도 가능할 것으로 판단된다. 제조된 ZITO/Ag/ZITO 다층막 투명전극을 적용한 2관능성 우레탄 아크릴레이트 기반 PDLC 시스템에 있어서 PDLC 층 두께 및 자외선(ultraviolet, UV) 세기 변화가 전기광학적 특성, 광중합 동력학 및 표면 형태학에 미치는 영향을 조사하였다. 15 ㎛의 PDLC 층 두께를 가지며 2.0 mW/c㎡의 UV 세기로 광경화된 PDLC 셀이 우수한 off-state 불투명도, 높은 on-state 투과도 및 양호한 구동 전압을 나타냈다. 또한, 본 연구에서 제조된 최적 조건의 PDLC 기반 스마트 윈도우는 광을 효율적으로 산란시킬 수 있는 2~5 ㎛ 크기의 양호한 마이크로 구조를 갖는 액정 droplet들이 형성되었으며, 이로 인해 우수한 최종 물성을 갖는 PDLC 셀이 제조되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.540-547
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• 2001

An experiment was conducted to investigate the effects of environmentally friendly agents (yucca extract, mineral feed additive, acidifier, nonspecific immunostimulating anionic alkali solution) on the growth performance, nutrient digestibility, nutrient excretion and carcass characteristics in growing-finishing pigs. A total of 125 pigs were allotted into 5 treatments with 5 replications, 5 pigs per pen in a completely randomized block design. Dietary treatments consisted of 1) control: basal diet, 2) YE: basal diet+120 mg/kg of yucca extract, 3) MFA: basal diet+50 mg/kg of mineral feed additive, 4) NIS: basal diet+3% of NIS (nonspecific immunostimulating anionic alkali solution), and 5) Acidifier: basal diet+0.5% of acidifier (organic acid complex). During the growing phase of the feeding trial, There were no significant differences in average daily feed intake (ADFI) and feed conversion ratio (F/G) among treatments, but the Acidifier group showed higher average daily gain (ADG) than the MFA group (p<0.05). During the finishing phase, there were no significant differences in growth performance among treatments, however YE supplementation increased ADG and F/G by 3.1 and 6.15%, respectively, when compared to control group. Proximate nutrients (dry matter, DM; crude protein, CP; crude ash, CA; crude fat, CF; gross energy, GE; calcium, Ca and phosphorus, P) digestibility did not show any significant differences among the treatments. And there were no significant differences in DM, N and P excretion as well. The supplementation of environmentally friendly agents tended to increase carcass weight compared to control group. Pigs fed MFA showed significantly heavier (p<0.05) carcass weight than those fed control or Acidifier diets. Addition of these agents except for NIS to diet for growing-finishing pigs caused a similar feed cost/kg weight gain than control group. Therefore, present study suggested that the optimum environmentally friendly agent would be yucca extracts, considering the effects on growth performance, nutrient digestibility, nutrient excretion, carcass characteristics and feed cost in growing-finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.217-223
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• 2006

Fifty castrated crossbred ($Landrace{\times}Yorkshire$) pigs, weighing an average of $60.6{\pm}3.1kg$ were allotted to one of five treatments in a randomized block design to examine the effects of dietary inclusion of 0.1% L-carnitine (50 ppm carnitine), 0.1% selenium-enriched yeast (0.3 ppm selenium), 0.1% Jujube fruit or 0.1% Hwangto (Red clay) on pig performance and carcass quality. All diets were based on corn, wheat, soybean meal and wheat bran and were formulated to supply 13.8 MJ DE/kg. Dietary supplementation did not influence daily gain (p = 0.57), feed intake (p = 0.52), or feed conversion (p = 0.32). Digestibility of dry matter (p = 0.60), organic matter (p = 0.74), crude protein (p = 0.76), crude fibre (p = 0.70) and energy (p = 0.75) were also unaffected by inclusion of any of the additives. Tissue samples taken from the longissimus muscle showed that the levels of carnitine (p = 0.0001) and selenium (p = 0.0001) were significantly higher with dietary inclusion of carnitine or selenium-enriched yeast. Dietary treatment did not affect dressing percentage (p = 0.33), carcass lean yield (p = 0.99) or first, $10^{th}$ and last rib midline backfat depth (p = 0.45, 0.82 and 0.47, respectively). Dietary treatment also did not affect the percentages of tenderloin (p = 0.37), bacon (p = 0.36), fat and bone (p = 0.56), picnic shoulder (p = 0.25), skirt (p = 0.80), fresh ham (p = 0.31) or ribs (p = 0.79). However, pigs fed the diet containing Jujube fruit had a higher percentage of Boston butt than pigs fed the carnitine or selenium supplemented diets (p = 0.01). Pigs fed added Hwangto had a higher (p = 0.04) percentage of loin compared with pigs fed supplementary selenium or Jujube fruit. Loin muscle from pigs fed carnitine had a significantly lower Hunter colour value for L (whiteness, p = 0.004) and a higher value for $a^*$ (redness; p = 0.069). The overall results indicate that supplementation with L-carnitine and selenium-enriched yeast can produce pork containing higher levels of carnitine and selenium, which could provide health benefits for consumers of pork without detrimental effects on pig performance.