• 한국수산과학회지
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• 제26권6호
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• pp.519-528
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• 1993

해수중에서 유처리제에 의해 유화${\cdot}$분산된 Bunker-C유의 생분해도와 이로 인해 나타나는 용존산소소비를 연구할 목적으로 국내에서 시판 중인 유처리제 및 국내 연안에 있어 유류오염사고의 주종을 이루고 있는 Bunker-C유에 대한 TOD분석과 원소분석을 행하고, 또한 Bunker-C유/유처리제 혼합물에 대해 천연해수를 이용한 생분해 실험을 행한 결과를 요약하면 다음과 같다. 1. 1mg의 Bunker-C유는 3.16mg의 TOD를 나타내는 반면에 1mg의 유처리제는 2.80mg의 TOD값을 나타내었다. 2. Bunker-C유는 $87.3\%$의 탄소와 $11.5\%$의 수소를 함유하였으며, 유처리제는 $76.5\%$의 탄소와 $12.2\%$의 수소를 함유하였다. Bunker-C유와 유처리제 중 어느 시료에서도 질소는 검출되지 않았다. 3. 천연해수 중에서 일정량의 Bunker-C유(4mg/l)에 대하여 유처리제를 $10:1{\sim}10:5$의 혼합비율로 첨가한 Bunker-C유/유처리제 혼합물에 관해서 정리하면, 혼합물의 $BOD_5$는 $0.34{\sim}2.06mg/l$였고 $BOD_{20}$는 $1.05{\sim}5.47mg/l$였다. 또한 혼합비율이 증가함에 따라 혼합물의 BOD는 증가하였다. 혼합물은 생분해도($BOD_5$/TOD)가 $3{\sim}11\%$로서 저율 분해군에 속하였다. 또한 혼합비율이 10:1에서 10:5로 증가함에 따라 혼합물의 생분해도는 $3\%$에서 $11\%$로 증가하였다. 혼합물의 탈산소계수($K_1$)는 $0.072{\sim}0.097/day$였으며, 혼합물의 최종산소요구량($L_o$)은 $1.113mg/l{\sim}6.746mg/l$로서 혼합비율이 증가함에 따라 최종산소요구량도 증가하였다.

• 대한약침학회지
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• 제19권3호
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• pp.207-212
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• 2016

Objectives: Acupuncture treatments are safe and effective for a wide variety of diseases involving autonomic dysregulation. Heart rate variability (HRV) is a noninvasive method for assessing sympathovagal balance. The low frequency/high frequency (LF/HF) spectral power ratio is an index of sympathovagal influence on heart rate and of cardiovascular health. This study tests the hypothesis that from rest to 30% to 50% of peak oxygen consumption, the nonlinear Conte-Zbilut-Federici (CZF) method of computing the LF/HF ratio is a more reliable index of changes in the HRV than linear methods are. Methods: The subjects of this study were 10 healthy young adults. Electrocardiogram RR intervals were measured during 6-minute periods of rest and aerobic exercise on a cycle ergometer at 30% and 50% of peak oxygen consumption ($VO_{2peak}$). Results: The frequency domain CZF computations of the LF/HF ratio and the time domain computations of the standard deviation of normal-to-normal intervals (SDNN) decreased sequentially from rest to 30% $VO_{2peak}$ (P < 0.001) to 50% $VO_{2peak}$ (P < 0.05). The SDNN and the CZF computations of the LF/HF ratio were positively correlated (Pearson's r = 0.75, P < 0.001). fast Fourier transform (FFT), autoregressive (AR) and Lomb periodogram computations of the LF/HF ratio increased only from rest to 50% $VO_{2peak}$. Conclusion: Computations of the LF/HF ratio by using the nonlinear CZF method appear to be more sensitive to changes in physical activity than computations of the LF/HF ratio by using linear methods. Future studies should determine whether the CZF computation of the LF/HF ratio improves evaluations of pharmacopuncture and other treatment modalities.

• KSBB Journal
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• 제14권3호
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• pp.309-314
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• 1999

Aspergillus niger를 이용하여 글루콘산 나트륨을 생산하는데 있어서 발효조건을 최적화하기 위해 포도당 농도의 영향을 조사한 결과 포도다으이 농도를 30-50 g/L로 유지시키는 유가식 발효를 통해 92.2%의 수율과 6.0 g/L/hr의 생산성을 얻을 수 있었다. 반면, 30g/L이하로 유지시킨 경우 발효수율이 25% 낮아졌으며 이는 탄소원인 포도당을 글루콘산 나트륨의 생산이 아닌 세포성장에 사용하기 때문인 것으로 생각된다. 균체의 접종농도에 따른 영향에 있어서는 20%의 접종농도에서 유도기를 6시간 가량 단축시키는 효과가 있었으나 발효 후반에는 과도한 균체농도로 인해 포도당이 더 이상 소비되지 않아 상당량이 배재 내에 남게 되는 등의 문제점이 관찰되었다. 이러한 현상은 과도한 균체의 성장으로 인한 산소전달이 저해 받기 때문이라 생각된다. 용존산소의 영향에서는 60~70%로 조절하여 주었을 때가 30%로 조절하였을 때보다 75%정도 높은 생산성을 나타내었다. 즉, 고농도의 산소수준을 유지하는 것이 글루콘산 생산에 도움이 되는 것을 알 수 있었다. 배양 중 포도당의 농도를 유지하기 위해 다양한 포도당 주입방법을 사용하였으나 기질로 사용되는 산소의 소모속도를 측정하여 이를 당소모속도로 환산한 후 당을 공급하여 주는 것이 매우 효과적이고 간편하여 실패가 적은 방법임을 증명할 수 있었다. 이와 같은 포도당 제어 방법은 산소를 반응기질로 사용하는 미생물 생물전환 공정에 일반적으로 유용하게 사용될 수 있을 것이라 사료된다. 상기한 조건에서 포도당을 사용하여 본 A niger ACM53을 통해 글루콘산 나트륨을 생산할 경우 글루콘산 나트륨 농도 255g/L, 최대 생산성 120g/L/hr 및 당전환수율 95%를 달성할 수 있었다.ch 배양기간에 40g/L의 glucose를 추가공급 했을 때 셀룰로오스 생성량은 15.3 g/L로 증가되었고 이때 $Y_{P/S}$는 0.26로 향상되었다. 이는 DO를 제어하지 않는 경우에 비하여 셀룰로오스 생성량이 1.5배 증가한 결과이다.>, President 품종 $284.24\;mg\%$ 및 Fiesta 품종 $206.34\;mg\%$로 나타났으며, 총 페놀 및 카로테노이드 함량은 Special과 Fiesta 품종보다 President 품종에서 가장 높은 함량을 나타내었다. 고전시대를 대표하는 직물로 족장 두르개, 쇼올, 안장덮개를 들수 있으며 이 직물들에서 뚜렷하게 외부영향 요인을볼수 있다. 즉 족장 두르개의 가장 정교한 단계에서 다이아몬드 무늬가 가장가리 가운데 모서리에 위치하여 9지점 배치를 이룬 것 쇼올의 경우 폭보다 길이가 긴 형태의 비전통적 모습을 나타낸 것 안장덮개에서 보여지는 여덟포인트 별 무늬도 외부의 영향을 받은예이다. 뛰어난 직조기술로 유명한 navajo인들은 변화에 잘 적응하는 특성을 갖고 있었다. 외부의 영향을 그들은 긍정적으로 받아들였고 자기 자신들의 필요에 맞도록 수정하여 정체감을 잃지 않으면서도 문화를 발전시켰다. 따라서 고전시대의 Navajo 직물은 고유적 요인과 외래적 요인의 조화를잘 나타내고 있으며 디자인의 탁월함이 세련됨 천연염료와 인조염료의 배\ulcorner에 의한 색상의 우월성 등으로 오늘까지 높이 평가되고있다.기능의 회 복증가는 기대하기 어려우나 IP와 유사한 심근괴사 범위 감소효과가 있으며 이러한 효과는 아마도 칼슘의 매개에 따라 PKC활성화가 일어남으로써 나타나는 것으로 생각된다. 점을 함께 고려하면 그룹 B에서의 더 큰 증폭

• The Korean Journal of Physiology
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• 제5권2호
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• pp.55-62
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• 1971

In an attempt to better understand the effects of whole body X-irradiation on the levels of non-protein sulfhydryl (NP-SH), non-protein disulfide (NP-SS) and oxygen consumption rate $(QO_2)$ of the mouse duodenum, and to clarify the possible radioprotective action of reduced glutathione (GSH), a whole body X-irradiation of 1,000r was given to albino mouse either singularly or immediately after injecting GSH intraperitoneally to mouse 1 mg per gm of body weight. NP-SH was measured by Ellman's method, NP-SS was measured by the electrolytic reduction method described by Dohan and Woodward, and $(QO_2)$ by the Warburg's standard manometric method. The experiment was performed at 1, 6, 12 and 24 hours post-irradiation, and the comparison was made with the control. The results thus obtained are summarized as follows: 1) Comparing with the intrinsic NP-SH level of $3.31{\pm}0.27{\mu}\;mol/gm$ wet weight in the duodenum of the normal mouse, either whale body X-irradiation or injection of GSH alone produced no significant change in NP-SH from the normal. However, when GSH was injected prior to X-irradiation, markedly elevated NP-SH levels were observed throughout the entire experiment with the highest value of $4.70{\pm}0.10$ at 6 experimental hours. 2) The normal value of NP-SS in the mouse duodenum was $1.57{\pm}0.17{\mu}\;mol/gm$ wet weight, while in the group where injection of GSH and X-irradiation were combined, NP-SS increased to $2.36{\pm}0.33$ at 12 hours and $2.15{\pm}0.53$ at 24 hours, showing the intermediate value between the GSH injection group and X·irradiation group. 3) The normal value of $(QO_2)$ was $4.16{\pm}0.73{\mu}l\;O_2/hr./gm$ D.W., and no noticeable change was observed comparing with the GSH injection group. However, in the group where X·irradiation alone was given, $(QO_2)$ of the duodenum increased significantly throughout the entire experiment with the highest value of $6.35{\pm}1.07$ at 6 experimental hours. When GSH was injected before X-irradiation was given, the levels of $(QO_2)$ were in the middle of the GSH injection group and X-irradiation group. 4) The above results suggest that GSH may be effective as a radioprotector in terms of NP-SH, NP-SS and $(QO_2)$ of the mouse duodenum.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2002년도 춘계 국제 학술대회
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• pp.26.1-28
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• 2002

Entrapped media with cellulous triacetate in which actived sludge was applied to induce operation factors and sewage treatment on site. The results are summarized as follows; The treatment efficiency of entrapped media is 92％, 90％ and 80％ at the size of 5mm, 7mm, and 12mm, respectively. Also, treatment efficient rate was increased by the packed amount of media in less than 30％ packed, while in more than 40％ packed that was decreased. It takes 10day to reach the steady states and it is less than the existing activated sludge method. The slopes of oxygen consumption rate are almost parallel both in the entrapped media and free sludge. When organic loading rate is less than 1.0 kg/㎥. d on site, it is achieved good removal rate independent of changes of loading rate.

• 동력기계공학회지
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• 제14권1호
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• pp.11-15
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• 2010

Our environment is faced with serious problems related to the air pollution from automobiles in these days. In particular, the exhaust emissions from the diesel engines are recognized as main cause which has a great influence on environment. In this study, the potential of biodiesel fuel and oxygenated fuel(ethylene glycol mono-n-butyl ether; EGBE) was investigated as an effective method of decreasing the smoke emission. The smoke emission of blending fuel(EGBE 0~20 vol-%) was reduced in comparison with diesel fuel and it was reduced approximately 64% at 2000 rpm, full load in the 20% of blending rate. On the contrary NOx emissions from biodiesel fuel and EGBE blended fuel were increased compared with diesel fuel. Torque and brake specific energy consumption(BSEC) didn't have large differences.

• 한국분무공학회지
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• 제5권3호
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• pp.9-16
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• 2000

In a SI engine, three-way catalyst converter has the best efficiency when A/F ratio is near the stoichiometry. The feedback control using oxygen sensors in the commercial engine has limits caused by the system delays. So it is necessary to control fuel quantity in accordance with intake air amount in order to reduce exhaust emission and improve the specific fuel consumption. Precise A/F ratio control requires measurement of air amount with respect to the cylinder and injection fuel according to the air amount In this paper, we applied nonlinear fuel injection model and developed the algorithm of A/F ratio control. This algorithm includes the methods of measurement of transient air mass flowing into each cylinder, of calculation of injection pulse width for measured air mass, and the method of feedback and engine control by using lambda sensor. Also we developed control program for IBM-PC by using C++ Builder, and tested it in the commercial engine.

• 한국환경보건학회지
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• 제28권1호
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• pp.79-84
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• 2002

Entrapped media with cellulous triacetate in which activated sludge was applied to induce operating factors and sewage treatment on site. The results are summarized as follows; The treatment efficiency of entrapped media is 92%, 90% and 80% at the size of 5mm, 7mm, and 12mm, respectively. Also, treatment efficient rate was increased by the packed amount of media in less than 30 % packed, while in more than 40 % packed that was decreased. It takes 10 day to reach the steady states and it is less than the existing activated sludge method. The slopes of oxygen consumption rate are almost parallel both in the entrapped media and free sludge. When organic loading rate is less than 1.0 kg/m$^3$ㆍd on site, it is achieved good removal rate independent of changes of loading rate.

• The Korean Journal of Physiology
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• 제6권1호
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• pp.39-42
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• 1972

This study was carried out on the energy expenditure and physical capacity of 504 persons from 17 occupations. The energy expenditure was measured by indirect calorimetry using a Douglas' bag and Scholander's gas analyser. The physical capacity was determined by the Harvard's step test and the maximum oxygen consumption using a treadmill. The assessment of the daily energy expenditure for each subject was made by the factorial method using a record of the activies throughout 24 hours of every survey day. The total daily energy expenditure is the sum of all energy expenditure. This was calculated by multiplying the caloric value of the metabolic rate by the time spent on each activity. Most of the occupations involved moderate or heavy work.

• 방재기술
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• 통권19호
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• pp.22-28
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• 1995

The rate of heat release is probably the single most important measure of fire hazard. Several tech-niques were developed for the measurement of rate of heat release, but were not suitable for fire test-ing purpose. Recently the application of oxygen consumption principle made it possible to development of well-characterized heat release rate measurement apparatus, the furniture calorimeter for large-scale fire tests and the cone calorimeter for bench-scale fire tests. The cone calorimeter can be used to determine the ignitability as well as heat release rate and smoke development, mass loss rate, combustion gas production etc. from burning materials. Thus, test method using cone calorimeter, an internationally recognized and accepted for the evalua-tion of fire properties, is a very promising tool for combustion study on various kind of materials and products.