본 연구 E. coli O157:H7에 대한 LP system(lactoperoxidae/thiocyanate/hydrogen peroxide)의 항균효과를 측정하기 위해 수행되었다. 초기 접종수준(10^2, 10^4, 10^7 cfu/ml), LP의 농도(10 ppm, 20 ppm, 30 ppm), 배지종류 (TSB, UHT milk, raw milk), 배양온도(5℃, 10℃, 15℃) 등에 따라 E. coli O157:H7에 대한 항균효과를 측정, 비교한 결과, 초기 접종수준을 10^2/ml으로 하였을 때와 LP의 농도를 10 ppm 및 5℃ 배양에서 항균력이 가장 높게 나타났다.

According to the Marine Traffic Safety Law, revised in 2009, Marine Traffic Safety Audit is introduced to secure the safe navigation, to prevent the marine accident and to maximize the efficiency of the port. In this audit system, marine traffic safety assessment is the most important scheme because the primary purpose of the audit system is to identify potential risk elements affecting safe navigation. Even though the reliability of audit result depends on the selection of assessment models, there are no independent assessment models for Korean coastal waters and most of models used in Korea currently are developed by foreign countries. Therefore, the development of the independent assessment model for Korean coastal water is required. This study, prior to the development of independent assessment model, aims to provide a basic data by comparing two foreign assessment models in Ulsan port area with marine accident statistics data.

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 (CO2), formaldehyde (HCHO), total volatile organic compounds (TVOCs) and particulate matter with diameter less than 10 ㎛ (PM10) 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 CO2 concentrations often exceeded 1500 ppm indicating importance of ventilation. Active activity of students during break time made the PM10 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.

Indoor air quality is affected by source strength of pollutants, ventilation rate, decay rate, outdoor level, and so on. Although technologies measuring these factors exist directly, direct measurements of all factors are not always practical in most field studies. The purpose of this study was to develop an alternative method to estimate these factors by application of multiple measurements. For the total duration of 30 days, daily indoor and outdoor NO2 concentrations were measured in 30 houses in Brisbane, Australia, and for 21 days in 40 houses in Seoul, Korea, respectively. Using a box model by mass balance and linear regression analysis, penetration factor (ventilation divided by sum of air exchange rate and deposition constant) and source strength factor (emission rate divided by sum of air exchange rate and deposition constant) were calculated. Subsequently, the ventilation and source strength were estimated. In Brisbane, the penetration factors were 0.59±0.14 and they were unaffected by the presence of a gas range. During sampling period, geometric mean of natural ventilation was estimated to be 1.10±1.51 ACH, assuming a residential NO2 decay rate of 0.8 hr-1 in Brisbane. In Seoul, natural ventilation was 1.15±1.73 ACH with residential NO2 decay rate of 0.94 hr-1. Source strength of NO2 in the houses with gas range (12.7±9.8 ppb/hr) were significantly higher than those in houses with an electric range (2.8±2.6 ppb/hr) in Brisbane. In Seoul, source strength in the houses with gas range were 16.8±8.2 ppb/hr. Conclusively, indoor air quality using box model by mass balance was effectively characterized.

A new method of automatic recording raingauge is developed to measure rainfall 1200mm full scale with high accuracy and resolution. The principle of new instrument is to detect a weight change of a buoyant weight according to a change in water level of raingauge measured by the use of a strain gauge load cell. This method has the advantage of increasing measurement accuracy, since no moving equipment is used. Laboratory test of the instrument was recorded 0.4% error of 190mm rainfall amount. The validity of new instrument was examined by comparing its measured values with values recorded by automatic weather station on June 24 to 25 2001 at Daegu Meteorological Station, when there is 148.3mm rainfall amount. In spite of much rainfall there is only 0.77mm difference of total rainfall amount. This instrument was accomplished high accuracy and resolution at field test in much rainy day.