• 한국광학회지
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• 제19권5호
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• pp.343-348
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• 2008

본 논문은E-PON용 버스트모드 광 수신소자를 개발하여 FTTH의 상용화에 기여하고자 연구되었다. 수신소자는 1.25 Gb/s 데이터 전송속도에서 E-PON의 10, 20 Km OLT Rx규격에 만족할 수 있도록 수신감도를 향상 시키기 위해 정전용량을 최소화하여 제작하였다. 수신감도는 비트 오류율이 $10^{-12}$이고 PRBS가 $2^5-1$일 때 -26 dBm, loud/soft ratio는 23 dB으로 측정되었다. Preamble time과 guard time은 각각 102.4 ns(128 bit)로 설정하였다. 일반적으로 광 수신소자에 주로 사용되는 정전용량이 0.53 pF인 포토다이오드와 정전용량이 최소화된 0.26 pF인 포토다이오드를 비교한 결과 정전용량이 0.26 pF인 포토다이오드로 제작된 버스트모드 광 수신소자 가 수신감도는 0.7 dBm, 대역폭은 190 MHz 더 향상되었다.

• 한국항해항만학회지
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• 제39권2호
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• pp.99-105
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• 2015

Until recently, thermal power plants have used high-rank coals to generate electricity. The switched to low-rank coals, primarily because of the rising coal price and the advancement of combustion technology. Therefore the thermal power plants need more fuels aspect of quantity and they are going to build extra infrastructure to deal with the increased fuel demand in their specialized ports. This paper introduces the process of the economic analysis as a case study for Hadong T/P(Thermal Power) Port. This study also evaluates investment for mew projects in ports. We analyze the costs and benefits of the port investment project using various information. And then we conduct the economic analysis using NPV(net present value), B/C ratio and IRR grounded in a financial theory. Out result of the economic feasibility shows that the new project of constructing a third berth in Hadong T/P Port has positive economic value. Additionally, this study conducts the sensitivity analysis of the major variables like cost, benefit and discount rate.

• 한국식품조리과학회지
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• 제24권5호
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• pp.722-728
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• 2008

This study was to investigate the quality characteristics of Seockryu-pyun by addition of different ratio of pomegranate juice and pomegranate concentrate (100%, 80%, 60%, 40%). Moisture and the pH increased as the content of pomegranate juice and pomegranate concentrate decreased respectivley. However, DPPH radical scavenging activity was decreased when adding pomegranate juice and pomegranate concentrate was decreased. With decreasing pomegranate juice addition, both the lightness(L) and yellowness(b) was significantly (p<0.05) higher, whereas, the redness(a) was significantly (p<0.05) lower. As addition of pomegranate concentrate was decreasing that lightness, a value and b value were higher. Texture profiles of hardness, adhesiveness, cohesiveness, gumminess, chewiness of Seockryu-pyun was not greatly showed significant difference among samples. Also, springiness was not significantly (p<0.05) different in any groups. For sensory evaluation, color and sourness were decreased as pomegranate juice and pomegranate concentrate was diluted. Seockryu-pyun, PJ3 made with addition of 60% pomegranate juice was the most preferred in overall acceptability. From the results, the most advisable mixture ratio of Seockryu-pyun was found as pomegranate juice 360 g (60%), water 240 g, mungbean starch 60 g and sugar 200 g.

• 국제초고층학회논문집
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• 제11권4호
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• pp.315-320
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• 2022

With the rapid development of urbanization the problems of pedestrian-level wind comfort and natural ventilation of tall buildings are becoming increasingly prominent. The velocity at the pedestrian level ($\overline{MVR}$) and variation of wind pressure coefficients $\overline{{\Delta}C_p}$ between windward and leeward surfaces of tall buildings were investigated systematically through numerical simulations. The examined parameters included building density ρ, height ratio of building α_H, width ratio of building α_B, and wind direction θ. The linear and quadratic regression analyses of $\overline{MVR}$ and $\overline{{\Delta}C_p}$ were conducted. The quadratic regression had better performance in predicting $\overline{MVR}$ and $\overline{{\Delta}C_p}$ than the linear regression. $\overline{MVR}$ and $\overline{{\Delta}C_p}$ were optimized by the NSGA-II algorithm. The LINMAP and TOPSIS decision-making methods demonstrated better capability than the Shannon's entropy approach. The final optimal design parameters of buildings were ρ = 20%, α_H = 4.5, and α_B = 1, and the wind direction was θ = 10°. The proposed method could be used for the optimization of pedestrian-level wind comfort and natural ventilation in a residential area.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.506-512
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• 1995

A cell aggregation factor produced by Aspergillus sp. LAM 94-142 was purified and partially characterized. The factor was purified about 15 folds from culture broth by IRA 420 and IRC 120 treatment, 1% NaCl added acetone precipitation, and Sepharose 4B column chromatography with overall yield of 48%. It was heteropolysaccharide consisted of mannose, arabinose, and glucose with a molar ratio, 31:17:2, and its molecular weight was estimated to be about 900,000 daltons by Sepharodse 4B gel filtration method. The optimum pH and temperature was 8 and 40$\circ$C, respectively. The factor was stable in pH range of 3-9 and at 100$\circ$C for 90 min. The cell aggregation activity of the factor was inhibited by the addition of Hg$^{2+}$, Fe$^{2+}$, Cu$^{2+}$, and some polypeptides such as milk casein or hemoglobin. The factor aggregated Bacillus subtilis, B. macerans, B. turingiensis, E. coli, Peudomonas aeruginosa, P. fluorescens, P. malophilia, and weakly aggregated Staphylococcus sp., Sarcina lutea, P. putida and Cryptococcus neoformnans, but it didn't aggregate various strains of Candida sp. and Saccharomyces sp.

• 한국지역사회생활과학회지
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• 제26권2호
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• pp.225-236
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• 2015

Materials for nutrition education to promote nutrition intake and prevent diseases in elderly individuals were developed, nutrition education was provided to 46 elderly females for 12 weeks, and its effects on the body composition, blood profile, and nutritional quality of subjects were qualitatively analyzed. After the education program, the weight of subjects decreased from 56.7 kg to 56.0 kg (p<0.001), their body fat dropped from 20.8 kg to 19.6 kg (p<0.01), their body mass index (BMI) declined from $25.2kg/m^2$ to $24.9kg/m^2$ (p<0.01), and their percentage of body fat decreased significantly (p<0.05). On the other hand, blood sugar showed a significant increase from 131.6 mg/dl to 141.8 mg/dl (p<0.05). Overall, the percentage of nutrition intake rose. In particular, the estimated energy requirement increased from 89.3% to 99.5% (p<0.05). Further, the contrast ratio of recommended intake showed significant increases in protein (p<0.01), phosphorus (p<0.05), vitamin $B_2$ (p<0.05), vitamin $B_6$ (p<0.05), and niacin(p<0.001), and that of adequate intake showed a significant increase in sodium (p<0.05). The nutrient adequacy ratio (NAR) showed a significant increase only in niacin (p<0.05), and the index of nutritional quality (INQ) showed significant increases in protein (p<0.05) and niacin (p<0.001). After the nutrition education program, a qualitative analysis of nutrients consumed by subjects was conducted. The results show improvements across the board except for the deficient intake of calcium and folic acid, suggesting that the nutrition status of subjects changed in a positive direction through the program. The implementation of this program for elderly individuals in a continuous and repetitive manner is expected to facilitate their nutrition management.

• 대한물리치료과학회지
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• 제7권2호
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• pp.711-725
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• 2000

The purpose of this study was to determine the effects of knee flexor isokinetic training on the mean peak torque of knee muscles and hamstrings-to-quadriceps ratio(H/Q ratio) in hemiplegia able to walk independently for more than 10 meters, to analyze the effect of torque increasing on functional aspects; fatigability and ambulation times, also. Forty-one adult subjects with hemiplegia secondary to a stroke partipated in this study. All participants were in/out patients at the College of Medicine, Pocheon CHA University, Pundang CHA General Hospital. The patients were allocated to two groups: one group exclusively for isokinetic maximal voluntary knee flexor training at $150^{\circ}$/sec(n=20) and the other exclusively for isokinetic maximal voluntary knee flexor training from $30^{\circ}$/sec to $150^{\circ}$/sec (n=21) gradually. The allocation was performed according to patient age, sex, affected side to minimize imbalance between the two training groups. Training was carried out from February 14th, 2000 to April 15th, 2000. Analysis of the data was done by means of t-test, x2-test, paired t-test, ANOVA, and multiple regression analysis. The results of this study were as follows: 1. There were no significant differences between the two groups in mean peak torque of knee muscles and relative decreases in knee extensor mean peak torque with increased knee flexor velocities before training (P<.05). 2.There was no significant differences between the two groups in the H/Q ratio, and no relative increases with increased knee flexor velocities before training. 3. there were significant changes in mean peak torque in group A after training(P<.05), but no significant differences as the velocity increased 4.there were significant changes in mean peak torque in group B after training(P<.05), but no significant differences as the velocity increased 5.there were no significant differences between the two groups, and no significant differences in mean peak torque increase rate between the groups with increased knee flexor velocities after training 6.H/Q ratio increased with increased knee flexor velocities between the two groups, but not statistically And there was no significant differences between the groups with increased knee flexor velocities 7.After training, Ambulation time and its decreasing rate decreased significantly in group B (P<.05) 8Before and after training, there was no significant differences between the groups in the fatiguability 9. In the multiple regression analysis, mean peak torque increase rate of the knee extensor and flexor were higher in group B than A(P<.05), and significantly higher with increased knee flexor velocities (P<.05) Also, training method influenced on Ambulation times decreases significantly(P<.05). Results indicated that knee flexor isokinetic training was effective to knee extensor and flexor mean peak torque increase in the hemiplegia able to walk independently for more than 10 meters. Therefore, we were able to conclude that gradual training from low to high velocity was more effective in the increase of mean peak torque of knee joint and decrease of Ambulation times than training only at high velocity.

• 대한환경공학회지
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• 제29권2호
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• pp.197-204
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• 2007

이 연구는 EBPR(enhance biological phosphorus removal)의 혐기조건, 호기/무산소 조건 사이의 상호작용을 알아보고 인의 제거 속도와 인 제거에 미치는 영향인자들을 Batch-test로 조사하였다. 실험결과 무산소단계에서 인의 흡수율은 호기 단계보다 50% 정도 낮았고, 인 방출과 인 흡수의 상관관계는 다른 논문들에 비하여 낮았으며, 계수 b는 높았다. Batch-test의 측정 결과 다른 논문들에 비하여 인 방출과 인 흡수의 상관관계$(R^2=0.557)$는 낮았고 계수b (b=8.4049)는 높았다. 또한, 하수에서 인의 중요한 결합 파트너는 Ca, $Mg^{2+}$, Al, Fe 그리고 $K^+$인데 이 실험 결과 칼륨, 마그네슘 그리고 암모니움은 인과 함께 증감함으로써 인의 방출과 흡수에 밀접한 관계가 있음을 알 수 있었다. 즉, 혐기 단계에서 0.2 mol $K^+Ion$ / mol $PO_4-P$ Ion과 0.21 mol $Mg^{2+}Ion$ / mol $PO_4-P$ ion이 측정되어 인에 대한 칼륨 및 마그네슘의 비율은 1 : 5 정도임을 알 수 있었다.

• Reproductive and Developmental Biology
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• 제31권1호
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• pp.35-41
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• 2007

본 연구는 인간 난관액 또는 자궁액 내에 존재하는 에너지원이 생쥐 2-세포기 배의 체외 발달에 미치는 영향을 조사하기 위하여 실시하였다. ICR 암 생쥐에 5 IU hCG 주사 후 $46{\sim}50$ 시간에 2-세포기 배를 회수하였다. 회수된 배는 3가지 배양 조건 [대조군: 0 mM Group A: glucose(G) 0.5 mM + pyruvate(P) 0.32 mM + lactate(L) 10.5 mM, Group B: G 3.15 mM + P 0.1 mM + L 5.83 mM]에서 72시간 배양하였다. 배양 24 시간에 상실배 출현율은 group A (72.3%)와 group B (56.6%)가 대조군(34.9%)보다 유의하게 높았다.(p<0.05). 그러나 48시간에 배반포기 배 출현율은 대조군(51.8%)이 group A (39.8%)와 group B (25.9%)보다 유의하게 (p<0.05) 높았다. 72시간에 투명대 부착 ($ZiB,\;41.0{\sim}51.8%$), 투명대 탈출 ($ZeB,\;18.1{\sim}32.5%$) 및 총 배반포기 배 출현율 ($68.7{\sim}73.5%$)은 실험군 간에 통계적인 차이가 없었다. 배반포기 배의 평균 세포수와 ICM 세포수는 group A (70.8, 13.4)와 group B (64.4, 11.8)가 대조군 (53.1, 5.7)보다 유의하게(p<0.05) 많았고, 통계적인 유의차는 없었으나 group A가 group B보다 많은 경향이었다. 총 세포수에 대한 ICM 비율은 group A(22.9%)와 group B(23.7%)가 대조군(14.2%)보다 유의하게(p<0.05) 높았다. 영양배엽(TE) 세포수($34.1{\sim}45.1$)는 실험군 간에 통계적인 차이가 없었다. ICM에 대한 TE 비율(ICM:TE ratio)은 대조군(1:6.0)이 group A(1:3.4)나 group B(1:3.4)보다 유의하게(p<0.05) 높았다. 생쥐 2-세포기 배를 배양하여 72시간까지의 배 발달율을 살펴보면 배양액에 에너지원을 첨가하는 것이 효과적이었으며, 자궁액 농도보다는 난관액 농도로 에너지원을 조절했을 때 배 발생 능력이 높은 경향을 보였다.

• 한국조리학회지
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• 제12권1호
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• pp.82-92
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• 2006

닭뼈 첨가에 따른 브라운 소스의 pH, 점도, 탁도, 색도와 관능검사를 실시하였다. 닭뼈가 증가함에 따라 pH는 5.11에서 5.72로 증가하여(p<0.05) 부패 세균의 최적 발육범위인 $6.8{\sim}7.0$보다 낮았다. 닭뼈의 양이 증가할수록 점도가 증가하여(p<0.05) 닭뼈의 양을 조절함으로써 원하는 점도를 얻을 수 있을 것으로 기대된다. 닭뼈의 비율이 높을수록 탁도가 탁하게 나타나 닭뼈가 소뼈보다 불투명한 용출성분이 많은 것으로 여겨진다. 닭뼈 함량이 증가함에 따라 Hunter's color "L" 값은 감소하였고 "a" 와 "b" 값은 증가하였다(p<0.05). 점도를 제외하고 색상, 향, 맛과 전체적인 평가는 소뼈의 양이 증가할수록 좋게 나타났지만(p<0.05) 닭뼈 : 소뼈 비율이 0.0 : 10.0과 2.5 : 7.5인 시료에서는 유의적인 차이가 없었다(p>0.05). 닭뼈와 소뼈를 2.5 : 7.5 비율로 제조한 소스는 관능적 성질 저하 없이 브라운 소스 제조가 가능하리라 여겨진다. 브라운 소스 제조에 닭뼈의 양을 조절하여 제조한다면 소뼈만을 사용한 소스와 비교하여 품질 저하 없는 소스 제조가 가능하리라 사료된다.