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Pollutant removal efficiency and installation cost are important factors to consider wastewater treatment process. However, practically during its operation, the input sources such as chemical use, amount of electricity used, waste sludge and so on are different according to characteristic of wastewater treatment process. Furthemore negative environmental influence such as resource depletion, energy consumption, air contaminant when generating electric-power were not considered as assessment factor to select the treatment process. This study analyzed environmental impact of MAR and A2O process using LCA (Life Cycle Assessment) in order to estimate contribution of potential environmental effects between A2O process and MBR process of sewage plant in Korea. Each process was set as system boundary and LCIA (Life Cycle Impact Analysis) by inputs and outputs was carried on. Specialized extruded values were obtained with the results of LCIA. A2O process has slightly higher environment load then MBR process with EP (Eutrophicaiton Potential) value of 7.09E-03 (kg PO4 3-eq/kg) for the fomer and 7.26E-03 (kg PO4 3-eq/kg) for the later. This was understood as treatment efficiency of MBR process has more higher then A2O process. However, MBR process showed its GWP of 9.13E-01 (kg CO2 eq/kg) which is approximately 5 time larger than of A2O process showing 1.60E-01 (kg CO2 eq/kg). For an analysis based on each influence category, contribution rate of water pollutant process about both processes had over 95% on EP, however, it is showed that A2O process had 85%, MBR process had over 96% on electricity related to global warming on GWP. As the results represented, it is concluded to allow for electricity consumption and water pollutant based on treatment process are Key contributor on WWTP. Sewage treatment process has been evaluated by treatment efficiency, cost of maintenance, etc., however, negative environmental effect of global warming can be passing out easily if electricity is only concerned on maintenance cost of WWTP. That is understood as a way that leads sustainable improvement in the waste water treatment which is one of national base facility with evaluating process efficiency as well as environmental anlaysis on LCA.

In this study, a 3x-nm after development inspection (ADI) wafer with focus exposure matrix (FEM) was inspected with both an advanced optical system and an advanced electron beam inspection (EBI) system. We found that EBI system could capture many more defects than the optical system and that it could provide more information about the reticle shot defect distribution. It has a high capture rate for certain critical defects, such as nano-bridges, that are insensitive to an optical system. We also studied the critical dimension (CD) variations caused by the optical inspection and by the EBI.

Indoor air quality has been addressed as an important atmospheric environmental issue and has caught attention of the public in recent years in Korea. Good indoor air quality in classrooms favour student's learning ability, teacher and staff's productivity according to other studies. In this study, each classroom at four different schools was chosen for comparison of indoor and outdoor air quality by means of source generation types such as new constructed classroom, using of cleaning agents and purchased furniture. Temperature, relative humidity (RH), carbon dioxide , formaldehyde (HCHO), total volatile organic compounds (TVOCs) and particulate matter with diameter less than were monitored at indoor and outdoor locations during lesson. HCHO was found to be the worst among parameters measured in new constructed classroom, HCHO and TVOCs was worst in classroom with new purchased furniture, and TVOCs was worst in classroom cleaned by cleaning agents, Indoor concentrations often exceeded 1500 ppm indicating importance of ventilation. Active activity of students during break time made the concentration higher than a lesson, Improvements and further researches should be carried out considering indoor air quality at schools is of special concern since children and students are susceptible to poor air quality.