• Environmental Engineering Research
• /
• 제24권4호
• /
• pp.582-590
• /
• 2019

Currently, the waterfront facility was constructed in New Songdo City, South Korea. It has the various water leisure areas and especially an artificial urban canal with filtered seawater by re-circulating flow system. However, due to excessive amount of nutrients from seawater combined with complicated geometry, it is highly vulnerable to deterioration of water quality. In this study, flow characteristics and pollutant transport were analyzed with comprehensive numerical models, MIKE 3 FM and ECO-lab. Based on these numerical results, notable sampling points were selected for field measurements and comparison between modeling and measured results were conducted. In addition, the integrated water quality evaluation index, Water Quality Index was applied to analyze various water quality issues. We also set up scenarios to control the two kinds of water quality factors, dissolved oxygen (DO), and total phosphorus (TP). As a result, the effect of 20% reduction of TP was less than 10% and it was almost ineffective for a year but it was reduced by up to 40% in case of scenario which DO is increased by 20%. Therefore, it was recommended to control the DO concentration, usually by applying re-aeration facility, rather than TP in artificial urban canal with seawater.

• 펄프종이기술
• /
• 제29권3호
• /
• pp.43-50
• /
• 1997

The purpose of this study was to decrease pollutants of effluents from KP bleaching. Multistage bleaching that combined with O, Eo, and C/D stage was conducted, after optimum bleaching conditions of O, Eo, and C/D stage were determined. Moreover the properties for bleached pulps and pollution level of bleaching effluent were measured by each standard method. Due to increase on the brightness and delignification of pulps by O, Eo, and C/D stage bleaching. It was possible that bleaching sequences were reduced from five stage to four stage. In addition to, OC/DEoD and OC/DEopD bleaching sequences had higher brightness than CEDED bleaching sequence. The pulps bleached by O and Eo stage had higher in tensile index than conventional bleaching sequences with the similar results in burst and tear index. While each bleaching sequences had little differences, bleaching sequences with Eo stage had higher in physical properties than with Eop stage. The pollution level measured by Chemical Oxygen Demand(COD), Biochemical Oxygen Demand(BOD) and Color of bleaching effluents were much lower in combined bleaching sequences of O, Eo and C/D stage than that of CEDED sequence. Particularly, a pollution index of bleaching effluents generated by C/DEoDEB and OC/DEopDED bleaching sequences were lower than that from the other bleaching sequences.

• 한국농공학회논문집
• /
• 제63권6호
• /
• pp.89-100
• /
• 2021

The conservation of stream habitats has been gaining more public attention and fish habitat suitability index (HSI) is an important measure for ecological stream habitat assessment. The fish habitat preference is affected not only by physical stream conditions but also by water quality of which HSI was not available due to the lack of field data. The purpose of this study is to estimate the HSI of Zacco platypus for water quality parameters of water temperature, dissolved oxygen (DO), and biochemical oxygen demand (BOD) using the water environment monitoring data provided by the Ministry of Environment (ME). Fish population data merged with water quality were constructed by spatio-temporal matching of nationwide water quality monitoring data with bio-monitoring data of the ME. Two types of the HSI were calculated by the Instream Flow and Aquatic Systems Group (IFASG) method and probability distribution (Weibull) fitting for the four major river basins. Both the HSIs by the IFASG and Weibull fitting appeared to represent the overall distribution and magnitude of fish population and this can be used in stream fish habitat evaluation considering water quality.

• Journal of Chest Surgery
• /
• 제23권1호
• /
• pp.22-32
• /
• 1990

Postoperative cardiac performance of cyanotic congenital heart disease is somewhat different from that of other cardiac diseases. For the evaluation of postoperative cardiac performance in the cyanotic congenital heart disease we measured cardiac output by thermodilution technique at 1, 4, 8, 12, 16, 20, 24, 36, 48 postoperative hours in 14 patients operated from Feb. 1989 to Nov. 1989 in The Department of Thoracic and Cardiovascular Surgery, Seoul National University Children`s Hospital. At the same time, we checked left atrial pressure [LAP], central venous pressure [CUP], and mixed venous oxygen saturation [SvO2] to detect correlation between them. Immediate postoperative cardiac index was 3.585 $\pm$ 0.945 L/min/m2, and it decreased maximally to 3.322$\pm$1.007 L/min/m2 at postoperative 16 hours. After then it increased and stabilized from 36 hours after operation, and its value was 4.426$\pm$1.358 L/min/m2. There were no correlations between cardiac index and left atrial pressure or central venous pressure. Between mixed venous oxygen saturation and cardiac index, there was no correlation in the early postoperative period but after postoperative 16 hours, there was significant correlation between them and correlation coefficients were 0.573 [16hrs], 0.743 [20hrs], 0.436 [24hrs], 0.560 [36hrs], 0.636 [48hrs], respectively. From these results, we concluded that in the corrective surgery of cyanotic congenital heart disease, cardiac performance was depressed in the early postoperative period. It improved from postoperative 16 hours, and stabilized from 36 hours after operation. During early postoperative period, mixed venous oxygen saturation should not be used as a predictor of cardiac performance but it could be used as a predictor of cardiac performance from 16 hours after operation.

• 한국의류학회지
• /
• 제3권2호
• /
• pp.1-7
• /
• 1979

본 연구의 목적은 여러 증류 솔기의 내연성을 Oxygen Index Test를 통해서 알아봄으로서 내연가공을 한 옷에 가장 이상적인 솔기의 종류를 제시하는 데 있다. 이 목적을 위해서 6가지 종류의 솔기를 내연가공한 옷감으로 만들어 실험하였으며 솔기 종류 이외의 변인으로는 솔기제작에 사용된 실(내연가공한 실과 일반 면사)과 세탁회수가 포함되었다. 솔기의 종류는 (1) 뉜솔(FF) (2) 가름솔에 zig-zag로 시접처리 (PZ) (3) overlook stitch로 박은 솔기(OL) (4) serger로 박은 솔기 (SG), (5) 내연가공한 binding을 사용한 쌈솔(TB) (6) 내연가공하지 않은 binding 을 사용한 참솔(UB) 등이였다. 실험 결과에 의하면 솔기 종류에 따라 O.I. value에 상당히 유의한(p<0.001) 차이가 있었으며, 실의 종류에 따라서도 상당히 유의한(p<0.001) 차이가, 세탁 회수에 따라서도 유의한(p<0.05) 차이가 나타났다. 또한 솔기 종류와 세탁, 솔기 종류와 실의 종류 사이에도 상당히 유의한(p<0.001) 상호작용이 있는 것으로 밝혀졌다. Newman-Keuls 겅증에 의하면 TB, FF, OL 사이에는 유의한 차이가 없으며 이들은 PZ, SG(내연가공하지 않은 실), UB보다 훨신 높은(p<0.01) 내연성을 보였다. SG의 경우 내연가공하지 않은 실을 사용했을 때는 PZ보다도 낮은 O.I. Value를 보였으나 내연가공한 실을 사용했을 때는 FF나 TB 만큼 높은 O.I. 결과가 나타났다. 또한 TB는 위의 솔기 중에서 가장 높은 O.I.를, UB는 가장 낮은 O.I.를 보임으로서 binding의 중요성을 나타냈다. 위의 결과로서 SG, FF, TB가 내연가공에 바람직한 솔기로 나타났으나 TB는 구성과정이 복잡하여 대량 생산에는 많이 사용되지 않으며 SG는 실의 내연가공 여부에 대한 규제가 필요한 것으로 나타났다. 또한 PZ나 UB, SG(일반 실사용)는 내연가공한 옷생산에 사용되지 않는 것이 타당하겠다.

• 중환자간호학회지
• /
• 제16권1호
• /
• pp.1-14
• /
• 2023

Purpose : This study aimed to compare peripheral pulse oxygen saturation (SpO₂) values, measured at different monitoring sites, and arterial oxygen saturation (SaO₂) of neurocritical patients. Methods : The study included 110 patients admitted to the neurosurgical intensive care unit of a university hospital. The patients' SpO₂ values were measured in their index fingers, both second toes, both earlobes, and foreheads, using the patient monitoring system. These values were compared with the standard value of SaO₂ measured using a blood gas analyzer. Data were analyzed using descriptive values, Pearson's correlation coefficients, Lin's concordance correlation coefficients (CCC), and Bland-Altman plots. Result : Regardless of the measuring site, SpO₂ was correlated with the paired measurements of SaO₂ (r=.40~.60, p<.001, CCC range=.40~.58). No significant bias in paired measurements of SpO₂ and SaO₂ was observed at all sites (-0.06~0.19%, p>.05). SpO₂ values at the left finger and right earlobe had the narrowest range, with a 95% limits of agreement (LOA) (left finger -3.04~2.93% and right earlobe -3.18~2.79%). SpO₂ at the index finger, on the side without an arterial catheter, had a narrower range of 95% LOA than that of the opposing finger (-3.00~2.97% vs. -3.73~3.26%). Conclusion : SpO₂ at the finger without an arterial catheter had the highest level of precision. This study suggests using the index finger, on the side without an arterial catheter, for pulse oximetry in neurocritical patients.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 1999년도 추계학술발표논문집
• /
• pp.194-204
• /
• 1999

The use of genetically cloned xylanase acquired from Bacillus strearthermophillus improves bleachability for oak kraft pulps. Combination of xylanase(X). oxygen(O), ozone(Z). peroxide(P), alkaline extraction(Eo. Eop), and chlorination(C/D, D) have been tested in a variety of bleaching sequences. The effectiveness of xylanase pre-treatment(XO) and post-treatment(OX) in oxygen bleaching is mainly compared. With xylanase treatment the brightness increase by 1.5-2.1% ISO in OZEP, OZEoP, OZEopP and OPZP sequences. There is only numerically difference of brightness gains between OX and XO sequences. With xylanase treatment chemical requirements for bleaching decrease by 42.6-48.6% in OC/DEoD sequence and 47.9-54.7% as active chlorine in OC/DEopD sequence at the same brightness. the reduction of bleaching chemicals is higher in XO sequence than those in OX sequence. Following xylanase treatment the viscosity increases from 11.7-12.0 mPa·s to 12.4-13.5 mPa·s and the brightness stability is considerably improved however the difference of effectiveness between XO and OX sequence is not present. Compared to tensile index vs tear index, the physical properties are similar for TCF bleaching sequences with and without xylanase treatments. However in OC/DEoD and OC/DEopD sequences the physical properties decrease with xylanase treatment. There is no difference in the physical properties between XO and OX sequences. COD, BOD and color of bleaching effluents increase slightly with xylanase treatment, however the discharge of COD end-load into environmental impact decrease.

• 대한기계학회논문집B
• /
• 제29권2호
• /
• pp.255-262
• /
• 2005

A comprehensive experimental and numerical study has been conducted to understand the influence of $CH_{3}Cl$ addition on $CH_4/O_2/N_2$ premixed flames under the oxygen enrichment. The laminar flame speeds of $CH_4/CH_{3}Cl/O_2/N_2$ premixed flames at room temperature and atmospheric pressure are experimentally measured using Bunsen nozzle flame technique, varying the amount of $CH_{3}Cl$ in the fuel, the equivalence ratio of the unburned mixture, and the level of the oxygen enrichment. The flame speeds predicted by a detailed chemical kinetic mechanism employed are found to be in excellent agreement with those deduced from experiments. Even though the molar amount of $CH_{3}Cl$ in a methane flame is increased, temperature at the postflame is not significantly varied, but the calculated heat release rate and emission index of NO are largely decreased for the oxygen enhanced flame. The function of $CH_{3}Cl$ as inhibitor on hydrocarbon flames becomes weakened as the level of the oxygen enrichment is increased from 0.21 to 0.5.

• The Journal of Korean Physical Therapy
• /
• 제23권4호
• /
• pp.23-28
• /
• 2011

Purpose: To investigate the effects of hyperbaric oxygen therapy (HBOT) on chronic low back pain in elderly patients with impaired functioning in daily life. Methods: 35 subjects with chronic low back pain were randomly allocated into two groups, HBOT group and Placebo group. We applied TENS and mechanical massage to the lower back in both groups. Then 35% oxygen at 1.4 ATA was given to the HBOT group and atmospheric oxygen at 1 ATA to the placebo group. Results: Comparing the HBOT group with the placebo group after performing interventions six times in 2 weeks, a statistically significant difference in the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) scores was observed between the two groups. There was a statistically significant difference in VAS and ODI scores (56% and 34.97% respectively) between the HBOT group and the placebo group. A statistically significant difference was ascertained in the degree of variables VAS and ODI in the HBOT group. Conclusion: Application of HBOT in chronic low back pain could be beneficial for reducing pain and could help in functional recovery.

• 대한물리의학회지
• /
• 제5권2호
• /
• pp.255-264
• /
• 2010

Purpose : The purpose of this study is to analysis effects of resistive exercise on cardiopulmonary fitness and cerebral artery blood flow velocity. Methods : Ten healthy university students had done resistive exercise without aerobic exercise over one year participated resistive exercise group and ten general university students, then were calculated oxygen consumption ($VO_2$) and respiratory exchange rate($VO_2/VCO_2$). After a week, they were measured Transcranial Doppler Ultrasonography(TCD) at moderate exercise(HRmax 50%), maximal exercise (HRmax 100%) for taking cerebral blood flow velocity. Results : In the comparison between groups, resistive exercise group showed significant higher oxygen consumption and lower respiratory exchange than controls(p<0.05). In resistive exercise group, oxygen consumption was significant negative correlation with cerebral artery pulsatory index(p<0.05). but, oxygen consumption was significant positive correlation with systolic blood flow velocity in controls(p<0.05). Conclusions : After considering all the factors, important value in resistive exercise is regular participation and help us increasing contingency response ability.