본 연구에서는 고등해석과 유전자 알고리즘을 이용한 강뼈대 구조물의 직접설계시스템의 최적화를 수행하였다. 본 연구에서 사용한 고등해석은 기하학적 비선형과 재료적 비선형을 동시에 고려한다. 직접설계 시스템의 최적화를 위해 유전자 알고리즘을 사용하였다. 목적함수로 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력, 처짐, 층간 수평변위 및 연성요구 조건을 고려하였다. 제안된 방법에 의해 나타난 결과를 다른 방법에 의한 것들과 비교해서 그 효율성을 증명하였다.

The effluent discharge standards of industrial wastewater has become more stringent since 2003. Many industrial wastewater treatment plants has been upgraded to advanced treatment facilities. There are high concentrations of nitrate(>200 mg/L) and ammonium(>50 mg/L) nitrogen in the acrylic fiber wastewater of H textile Co. Wastewater from acrylic fiber industry containing acrylonitrile, which may affect the subsequent biological treatment process. Manufacturing of acrylic fiber also produces shock loadings. Excessive acrylonitrile and polymer debris produced in the polymerization process was screened, coagulated with CaO and settled down. A preaeration system was added to treat this high pH effluent to remove volatile organic compound and ammonia nitrogen by the air stripping effect. It was found that nitrification rate was not sufficient in the Anoxic/ Oxic(AO) process. One denitrification tank was converted to nitrification reactor to extend HRT of nitrification. Nitrification rate of ammonia nitrogen was promoted from 32% to 67% by this modification and effluent nitrogen concentration was well satisfied with the effluent standards since then.

Advanced oxidation processes involving O3/H2O2 and O3/catalyst were used to compare the degradability and the effect of pH on the oxidation of 1,4-dioxane. Oxidation processes were carried out in a bubble column reactor under different pH. Initial hydrogen peroxide concentration was 3.52 mM in O3/H2O2 process and 115 g/L (0.65 wt.%) of activated carbon impregnated with palladium was packed in O3/catalyst column. 1,4-dioxane concentration was reduced steadily with reaction time in O3/H2O2 oxidation process, however, in case of O3/catalyst process, about 50～75% of 1,4-dioxane was degraded only in 5 minutes after reaction. Overall reaction efficiency of O3/catalyst was also higher than that of O3/H2O2 process. TOC and CODCr were analyzed in order to examine the oxidation characteristics with O3/H2O2 and O3/catalyst process. The results of CODCr removal efficiency and ΔTOC/ΔThOC ratio in O3/catalyst process gave that this process could more proceed the oxidation reaction than O3/H2O2 oxidation process. Therefore, it was considered that O3/catalyst advanced oxidation process could be used as a effective oxidation process for removing non-degradable toxic organic materials.

The degradation of Rhodamine B (RhB) in water was investigated in laboratory-scale experiments, using five advanced oxidation processes (AOPs): UV/H2O2, fenton, photo-fenton, UV/TiO2, UV/TiO2/H2O2. The photodegradation experiments were carried out in a fluidized bed photoreactor equipped with an immersed 32 W UV-C lamp as light source. Initial decolorization rate and COD removal efficiency were evaluated and compared. The results obtained showed that the initial decolorization rate constant was quite different for each oxidation process. The relative order of decolorization was: photo-fenton > UV/TiO2/H2O2 > fenton > UV/H2O2 > UV/TiO2 > UV > H2O2. The relative order of COD removal was different from decolorization: photo-fenton ≒ UV/TiO2/H2O2 > UV/TiO2 > fenton > UV/H2O2. The photo-fenton and UV/TiO2/H2O2 processes seem to be appropriate for decolorization and COD removal of dye wastewater.

선박에서 발생하는 오·폐수를 처리하기 위하여 생물학적 질소 및 인의 제거공정으로 사용되고 있는 연속 회분식 공정을 이용하여 유기물의 제거 특성과 산소 소모량, 반응조내에서 우점하고 있는 Bacillus sp.균주의 상태를 알아보기 위하여 Lab-sacle로 수행하였다. 반응조에서 COD의 제거효율은 92.0%, 암모니아성질소는 90.0%, 총질소의 제거효율은 84.0%, 인의 제거효율은 93.0%로 나타났다. Bacillus sp.를 이용한 SBR를 사용한 선박폐수의 처리효율은 안정적이었다. 포기시에 SBR 내의 pH는 초기의 8.1에서 30분동안에 pH는 7.0으로 감소하였다. 무산소 단계인 3단계와 4단계에서 pH는 증가하기 시작하여 최종적으로 pH는 7.3으로 유지되었다. TOC제거량에 대한 슬러지 생성량은 약0.36kg·MLSS/kg·TOC으로 나타났으며 낮은 슬러지 발생율과 높은 슬러지 침강성을 나타내었다. 반응조에서 바실러스균의 평균 우점율은 24.2%로 나타났고 각 반응단계에서 안정적인 처리효율을 얻을 수 있어 충분히 우점화 되었다고 판단할 수 있었다.

국제해사기구(IMO)는 해상안전과 해상보안 및 해양오염방지를 달성하기 위해 조직된 유엔산하 전문기구로서 책임과 보상 및 국제 해상교통의 간소화를 포함한 법적문제도 다루고 있다. 그러나 우리나라는 IMO 관련 분야를 전문적으로 연구하는 조직이나 연구기관이 없어서 급변하는 해운환경에 능동적으로 대처하지 못하였고, 이에 대처할 수 있는 전문가의 부재로 막대한 경제적 손실을 입고 있었던 것이 사실이다. 하지만 2001년 제22차 IMO 총회에서 처음으로 주요해운국가그룹인 A그룹 이사국으로 선출되고 2003년 11월 제23차 IMO 총회에서 A그룹 이사국으로 재진출하는 쾌거를 이루면서, IMO 내에서의 역할 부담 빛 국제적 위상강화를 확고히 하고 있다. 이를 계기로 삼아 A그룹 이사국으로서의 위상을 확고히 지키기 위하여, 해운선진국이라 할 수 있는 미국, 영국 및 일본의 해사행정체계를 IMO 연구 및 대응체계와 더불어 살펴본다면, 향후 우리나라의 시스템을 정비하는데 도움이 되리라 생각된다. 이에 이 연구에서는 IMO가 주도하고 있는 해운·조선산업에 대한 우리나라의 대응 방안 수립에 도움을 주고자 주요 해운선진국의 해사행정체계, 특히 IMO 연구 및 대응체계에 관한 각국의 자료를 수집하여 비교·분석한다.

The performance of ozone contactor in ozone-BAC advanced water treatment process was evaluated by the degree of decomposition of organic matters. The degree was measured by the analyses of UV254 absorbance and the concentrations of DOC and BDOC for the sand filtered water and the ozone treated water, respectively. In addition, the ozone concentration in the contactor, required for the maximum BDOC concentration, was selected as the optimum concentration, and the appropriate residential time of ozone treated water in a reservoir was recommended based on the residual ozone concentration in the treated water. The following results were obtained from the pilot scale experiments. By ozonation UV254 absorbance was decreased, and BDOC concentration was increased. The change of DOC concentration by ozonation was negligible, but the excess input of ozone resulted in the removal of the small amount of BDOC by complete oxidation. The optimum ozone concentration was 0.58 mg O3/mg DOC. In order to remove residual ozone, 20 minutes of the residential time were enough after ozonation.

Statistical analysis between operating parameters and effluent quality on advanced wastewater treatment plant was performed. Through factor analysis four factors derived varimax rotation were selected each plant. Four components explained 80%, 82% of the total variance of the process, respectively. The components on MLE plant were identified in the following order：1) HRT increase and BOD load decrease by influent decrease, 2) Biomass, 3) SVI increase by internal return increase, 4) Microbial diversity by SRT increase. On A2O plant, we defined them as follows: factor 1, high MLSS by return rate increase, HRT increase by influent decrease; factor 2, biomass; factor 3, BOD of influent; factor 4 was relate to DO.

This study was to analyze the right or wrong of gray-water treatment by applying BPBE electrode cell to the effluence water in the terminal disposal plant of sewage. The results were as follows : The best result was obtained with applied voltage 40V and detention time 6 minutes for the BPBE electrode cell which has the graphite-plate in main electro-de, packing coconut activated carbon. The elimination rate of COD of Al-plate was higher than that of graphite-plate in main electrode. The result of electrolysis for 3 hour in parallel circuit showed the using possibility of gray-water according to each elimination rate : COD 59%, T-N 69 %, T-P 69%. The BPBE electrode cell with the Al-plate in main electrode made the best effect for the elimination of algae in lake water and algae were not occurred in electrolytic water

The advanced oxidation process (AOP) using ozone combined with hydrogen peroxide and ultraviolet treatment were evaluated for biodegradable dissolved organic carbon (BDOC) formation and dissolved organic carbon (DOC) removal. Oxidation treatment were conducted alone or combination with ozone, hydrogen peroxide and ultraviolet processes. Ozone dosage of ozone process was varied from 0.5㎎/ℓ·min to 5㎎/ℓ·min. Ozone/hydrogen peroxide process was done using 20㎎/ℓ of hydrogen peroxide concentration. Ozone/ultraviolet process was irradiated with 12mW/㎠ of density and 254nm. Ozone dosage was varied from 0.5㎎/ℓ·min to 5㎎/ℓ·min at the ozone/hydrogen peroxide and ozone/ultraviolet processes too. Contact time of all the process was 20 minutes. Oxidation treatment were performed on microfiltration effluent samples. BDOC formation was reached to an optimum at ozone dosage of 1.5㎎/ℓ·min in the ozone/hydrogen peroxide process and 1㎎/ℓ·min in ozone/ultraviolet process, after which BDOC formation was decreased at higher ozone dosages. But BDOC formation was increased with ozone dosages increasing in ozone process. The efficiency of DOC removal was higher AOPs than ozone process. Ozone/ultraviolet proces was the highest for DOC removal efficiency in each process. THMFP removal efficiency by ozone/ultraviolet process was higher than that by each of ozone process and ozone/hydrogen peroxide process.

The Photodegradation efficient of total organic compounds in the drinking water has been studied using the methods of photocatalytic reaction and laser beam irradation. The results are summarized as follows; 1. The photodegradation efficiency of total organic compounds shows as 50% to 80% as within one hour and after this the efficiency is decreased slowly. 2. The photodegradation efficiency of total organic compounds shows as 65 to 90% within 3.3min. when Nd : YAG beam is irradiated to the water layer. 3. An excellent observation of the organic compound removal efficiency gives revealed in that case of the longest wavelength of 532nm is irradiated among the three kinds of laser beam sources of 532nm, 355nm and 266nm. 4. The organic compound removal efficiency shows high in the case of UV beam irradiation in the thin layer of water. However the efficiency is not depended on the thickness of water layer severely. 5. The removal efficiency of the organic compounds in the direct irradiation shows higher than the indirect irradiation in the case of UV beam, but the efficiency is not depended on the direction of irradiation in the case of Nd : YAG beam irradiation.

In recent years increasing production and disposal of wastewater have caused an accelerated eutrophication of receiving waters. Therefore, in order to alleviate the detrimental impact of wastewater discharge, there is an increasing demand for removing the main nutrients, nitrogen and phosphorus, as well as the organic content of the waste water prior to disposal. This is effectively achieved by extended conventional treatment technology. However, the working expenses and energy requirements of such advanced treatment systems are rather high. So in a sparsely populated rural community is required development of wastewater treatment system combined with the regional characteristics. In this study, the systems are planted with Reeds and Amaryllis in A.C and estimated purification potential of system. The results obtained are as follows. BOD removal rate is 20% in the early stage, the last removal rate is 35% in A.C process and is 65% in Amaryllis+A.C process and is 50% in Reed+A.C process. T-N removal rate by Amaryllis is average 2.6g/㎡·d, T-N removal rate by Reed is average 1.76g/㎡·d. T-P removal rate by Amaryllis is average 0.27g/㎡·d, T-P removal rate by Reed is average 0.25g/㎡·d. BOD removal rate constant with retention time is 1.4494(l/d), T-N removal rate constant is 0.5428(l/d), T-P removal rate constant is 0.5287(l/d)

The study of flocculation kinetics is of fundamental interest in the field of water treatment, because rational study of the factors affecting the coagulation process should be based on the rate of particle growth. The effect of sulfate on flocculation kinetics were examined using ferric nitrate as a coagulant to coagulate kaolin clay in water under several experimental conditions. Both the particle size distribution data obtained from the AIA and the on-line measurement of turbidity fluctuation by the PDA were used to measure flocculation kinetics. Results show that sulfate ion added to the kaolin suspension played an important role in the flocculation process, not only improving flocculation kinetics at more acidic pH levels but also changing surface charge of particles. The kinetics of flocculation were improved mainly by the enhanced rate and extent of Fe(Ⅲ) precipitation attributed to the addition of sulfate, and thereby, better interparticle collision frequency, but little by the charge reductions resulting from the sulfate addition. The increase in sulfate concentration beyond 3×10 exp (-4)M (up to 2×10 exp (-3)M) did not induce further improvement in flocculation kinetics, although the higher concentrations of sulfate ion substantially increased the negative ZP value of particles.