• Journal of Microbiology and Biotechnology
• /
• v.10 no.3
• /
• pp.349-354
• /
• 2000

Abstract A facultative alkalophilic gram-negative Vibrio metschnikovii strain RH530, isolated from the wastewater, produced several alkaline proteases (VAP) including six alkaline serine proteases and a metalloprotease. From this strain, high yielding YAP mutants were isolated by NTG treatment. The isolated mutant KS1 showed nine times more activity than the wild-type after optimization of the culture media. The production was regulated by catabolite repression when glucose was added to the medium. The effects of several organic nitrogen sources on the production of the YAP were investigated to avoid catabolite repression. The combination of 4% wheat gluten meal (WGM), 1.5% cotton seed flour (eSF), and 5% soybean meal (SBM) resulted in the best production when supplemented with 1% NaCl. The YAP showed a resistance to surfactants such as $sodium-{\alpha}-olefin$ sulfonate (AOS), polyoxy ethylene oxide (POE), and sodium dodecyl sulfate (SDS), yet not to linear alkylbenzene sulfonate (LAS). However, the activity of the YAP was restored completely when incubated with LAS in the presence of POE or $Na_2SO_4$. The YAP was stable in a liquid laundry detergent containing 6.6% SLES (sodium lauryl ether sulfate), 6.6% LAS, 19.8% POE, and stabilizing agents for more than two weeks at $40^{\circ}C$, but the stability was sharply decreased even after 1 day when incubated at $60^{\circ}C$. A washing performance test with the YAP exhibited it to be a good washing power by showing 51 % and 60% activity at $25^{\circ}C{\;}and{\;}40^{\circ}C$, respectively, thereby indicating that the YAP also has a good detergency at a low temperature. All the results suggest that the YAP produced from the mutant strain KSI has suitable properties for use in laundry detergents.rgents.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.5 no.1
• /
• pp.53-61
• /
• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from l0th Sept. to 30th Sept. in 1996. The research was used questionare method and analysis was used prequency analysis and cross table method by SPSS (scientific statistics). The foodwaste of householdwaste account for 24.8%, and the magnitude by the kinds of garbage were waste from pre-cocking stage, fruitshell, foodwaste remained after eating, septic foodwaste during storage. The more the housewives'age are young, foodwaste volumne were much. Most remained foodwaste after eating were soup and pot stew. The main cause of foodwaste production was overvolumne cooking. 88.8% of answers think that a menu can be useful to reduce foodwaste. The survey showed that 87.3% of answers put into the meter-rate bag after removed wetness of garbage. 84.1% of answers thought that the recycling of foodwaste needed, but the practical housewife was only 21%. For the suitable treatment of foodwaste, Survey showed that the consistent policy of goverment and continuous publicity was needed essentially, and that the public notice of TV or radio was effective. All of answers would like to participate in recycling of foodwastes whether public-posting or personal-posting. To set up vessel of posting at household, the proper purchase price and space of institution are needed, also the solution of sanitory & aesthetic problem and the collection of composting-product must be achieved smoothly.

• Safety and Health at Work
• /
• v.7 no.4
• /
• pp.372-380
• /
• 2016

Background: The aim of this study was to estimate the number of workers exposed to diesel engine exhaust (DEE) by industry and year in the Republic of Korea. Method: The estimates of workers potentially exposed to DEE in the Republic of Korea were calculated by industry on the basis of the carcinogen exposure (CAREX) surveillance system. The data on the labor force employed in DEE exposure industries were obtained from the Census on Establishments conducted by the Korea National Statistical Office from 1993 to 2013. The mean values of prevalence rates adopted by EU15 countries were used as the primary exposure prevalence rates. We also investigated the exposure prevalence rates and exposure characteristics of DEE in 359 workplaces representing 11 industries. Results: The total number of workers exposed to DEE were estimated as 270,014 in 1993 and 417,034 in 2013 (2.2% of the total labor force). As of 2013, the industry categorized as "Land transport" showed the highest number of workers exposed to DEE with 174,359, followed by "Personal and household services" with 70,298, "Construction" with 45,555, "Wholesale and retail trade and restaurants and hotels" with 44,005, and "Sanitation and similar services" with 12,584. These five industries, with more than 10,000 workers exposed to DEE, accounted for 83% of the total DEE-exposed workers. Comparing primary prevalence rates used for preliminary estimation among 49 industries, "Metal ore mining" had the highest rate at 52.6%, followed by "Other mining" with 50.0%, and "Land transport" with 23.6%. Conclusion: The DEE prevalence rates we surveyed (1.3-19.8%) were higher than the primary prevalence rates. The most common emission sources of DEE were diesel engine vehicles such as forklifts, trucks, and vans. Our estimated numbers of workers exposed to DEE can be used to identify industries with workers requiring protection from potential exposure to DEE in the Republic of Korea.

• Applied Chemistry for Engineering
• /
• v.9 no.3
• /
• pp.413-418
• /
• 1998

Methoxy polyoxyethylene dodecanoates are a kind of nonionic surfactants obtainable from reaction of fatty acid methyl ester with ethylene oxide utilizing a solid catalyst. Methoxy polyoxyethylene dodecanoates have economical advantage compared with polyoxyethylene dodecyl ethers using fatty alcohol. In this work, the solubilizing capacity concerned with phase behavior of ternary systems composed of nonionic surfactant/water/oil, interfacial tension and detergency at the phase inversion temperature(PIT) were investigated and compared with those of polyoxyethylene dodecyl ethers in order to confirm the applicability of methoxy polyoxyethylene dodecanoates in the detergents. Methoxy polyoxyethylene dodecanoates showed the solubilizing capacity of 10~18% for hexadecane which were about 6% higher than polyoxyethylene dodecyl ethers. At the PIT condition, methoxy polyoxyethylene dodecanoates' interfacial tension were 0.0124~0.0176 dyne/cm while polyoxyethylene dodecyl ethers have the value of 0.013~0.0163 dyne/cm and methoxy polyoxyethylene dodecanoates showed higher detergency of 82.1~83.2% than polyoxyethylene dodecyl ethers of 76.5~77.3%. The good detergency performance of methoxy polyoxyethylene dodecanoates would be due to the higher oil solubilizing power and lower interfacial tension than polyoxyethylene dodecyl ethers at the PIT condition.

• Journal of Korea Water Resources Association
• /
• v.44 no.2
• /
• pp.125-134
• /
• 2011

The paper is to estimate willingness-to-pay (WTP) for residential water quality improvement in Busan, using non-parametric approach. There are several significant advantages of non-parametric approach, compared to parametric methods. That is, no probability distribution assumption is necessary so that there are no needs to assume or test goodness of fit, model specification and heteroscedasticity statistically. For the reliability and the validity of contingent valuation method a survey was conducted for 665 respondents, who were sampled by stratified random sampling method, by personal interview method. The result of mean WTP for residential water quality improvement in Busan was estimated to be 3,190 won to 3,331 won per month per household, while median WTP being 1,750 won. Provided that our sample is broadly representative of the Busan's population, an estimate of the annual aggregated benefit of residential water improvement for all Busan households is approximately 50.2 billion won in case of mean WTP or 27.5 billion won in case of median WTP.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.17 no.1
• /
• pp.55-70
• /
• 2018

Recently, as shared transportation services has expanded, integrated mobility services that link personal transportation and public transportation are paid attention. To do this, it is necessary to analyze trip mode chaining behavior. This study analyzed the characteristics of the trip mode chaining behavior using the 2010 travel diary survey in Seoul, and analyzed factors to affect mode choice of trip chaining through the multinomial logit model. The transportation means were classified into passenger cars, city buses, intercity buses, railways, taxis, and others, and 25 trip mode chaining types were identified. Among them, the trip share connected between city bus and railways was the highest. It was also found that the trip mode chaining occurred mainly at commuting and in the morning and afternoon peak. According to the model results, the mode choice of trip chaining is significantly influenced by individual attributes (sex and age), household attributes (car ownership and income), trip attributes (trip purpose, trip time and trip length), and arrival area attributes (number of subway lines and bus lines, ratio of commercial area, land use mix and central region).

• Journal of the Economic Geographical Society of Korea
• /
• v.1 no.2
• /
• pp.21-42
• /
• 1998

This paper aims at examining the regional comparison of the business organization of retailing in the Seoul and Taegu metropolitan areas, as an attempt to understand regional structure of retailing within metropolitan areas which represents the suburbanization. On the national level, retail sales have concentrated on larger metropolitan area, the Seoul metroplitan area, the first largest metropolitan area, having higher sales for population scale. While the Taegu metropolitan area, the third largest metropolitan area, appears to lower retail sales for population scale. In order to confirm such phenomenon, this paper is to analyze and to compare the industrial composition of retailing by industry in 1991 of Seoul with that of Taegu. And this paper is to analyze the regional comparison of business organization of retailing: the percents of establishments under four employees, of juridical establishments, of employees of ordinary times, the annual sales per establishment of retailing. And the characteristics of business organization of retailing by industry are analyzed by principal components analysis, and the explanation of the types with component in each district(city, county, ward) is analyzed by cluster analysis(Ward method). The data of 1991 were obtained from the statistics in the Report on Establishment Census(Vol.3 Wholesale and Retail Trade) published by the National Statistics Office. The results are as follows: 1. The composition of retailing by industry in Seoul metropolitan area by annual sales in 1991 is characterized as appeared very higher composition rates of retailing of textiles, clothing, footwear and apparel accessaries', ‘retailing of furniture, home furnishings and equipment’, retailing of jewellery and watches’, ‘retailing of printed matter and stationery’, ‘retailing of personal transport equipment and gasoline service stations’, and ‘general merchandise stores’. But in Taegu metropolitan area, ‘retailing of food, beverages and tobacco’, ‘retailing of drugs, cosmetics and other chemical goods’, 'retailing household fuel’, and ‘genernal retail trade, n.e.c.’appears very high. Therefore Seoul metropolitan area has larger business scale and retailing of shopping goods has developed than Taegu metropolitan area.

• Journal of Preventive Medicine and Public Health
• /
• v.10 no.1
• /
• pp.3-15
• /
• 1977

In order to find out health problems among inhabitants in slum areas in Kwanak-Ku, Seoul, a series of health survey was conducted upon 510 households by interview from March to December, 1976. The results obtained were as follows: 1. Employments of householders were unstable; Out of 508 householders, 164(32.3%) were unemployed and 184 (36.2%) were daily or temporary employees. 2. Average number of households per house was 2.0 and average area of residential room per person was $4.0m^2$. 3. 476(93.3%) out of 510 households were supplied with tap water and rest of them made use of ground water as a source of drinking water. 4. Only 279(18.3%) out of 1527 live births were delivered at medical facilities, 496(32.7%) were at home attended by doctors or midwives and 358(25.1%) took prenatal care. The above findings were worse in urban slum area than in other urban area of relatively high economic level, but were better than in rural area of less medical facilities. 5. Initiation of treatment were delayed until their illnesses were advanced in most of the households, 472(92.5%) out 510. In the early stage of the illness, 131(25.6%) of the house-holds sought physicians in their clinics or general hospitals and 250 (40.9%) visited chemists, to toy drugs at first hand. Frequency of visits to physician increased to 52.8% as the disease aggravated in later stages. 6. Cost of medical expenditure per household amounted to 815 won, and was paid to, in the order of chemists, physicians, chinese herb stores, chinese herb doctors. 7. Concerning the health knowledge of the inhabitants, 273(53.9%) out of 506 respondents were aware of the infectivity of pulmonary tuberculosis, and 68(13.4%) of them checked regularly their chest findings by X-ray at least once every two years. 8. As for the family planning, although 448(87.3%) out of 510 respondents were in favor of it, 215 (41.8%) of them were actually practicing contraception. 9. About 40.6% (125 respondents) of them obtained information and knowledge concerning contraception through personal contact with family planning workers. 10. Nutritional status of housewives was generally poor: 49(38.3%) out of 128 housewives were found to be anemic and average serum protein level was $7.5{\pm}0.82g/dl$.

• Journal of Preventive Medicine and Public Health
• /
• v.21 no.2 s.24
• /
• pp.431-441
• /
• 1988

The purpose of this study was to compare the difference of two survey methods for health services research. Data were collected by means of two types of household survey conducted from March 11 to September 19, 1985. A probability sample of 30,613 persons was taken from 180 Enumerated Districts designated by the Economic Planning Board. The sample was divided into two groups systematically. One group was surveyed by the self-administered questionnaire and the other group was interviewed. Response rates were 81.4% and 90.6% respectively. The data were analysed by the ratio of the results of the self-administered survey to those of the interview survey. No difference was observed in sex, age, residence, or occupation between the two groups. However the respondents' characteristics were statistically different between the two groups. The major findings of this study are as follows : 1. The morbidity rate was 142.5 per 1,000 persons during the two week period by the self-administered questionnaire survey and 74.3 per 1,000 persons with the interview survey method. The ratio of the morbidity rate by the self-administered questionnaire to that by the interview was 1.92, and the difference between the two rates were due to the personal characteristics. 2. The out-patient utilization rate was 10.2 visits per person per year by the self-administered questionnaire survey and 5.4 by the interview survey, and the ratio was 1.89; the admission rate was 3.2 times per 100 persons per year by the self-administered questionnaire survey and 1.9 times by the interview survey, and the ratio was 1.68. Differences due to the sociodemographic characteristics were greater in the out-patient utilization rates than in the adimssion rates. 3. Percentages of effective medical care demand were 90.2% in the self-administered survey and 92.3% in the interview survey; the ratio was 0.98 which was less than that of the morbidity rate and medical care utilization. But, differences of effective medical care demand occurred in persons with no occupation, and aged or low educated respondents. 4. Respiratory illness had the highest frequency in the two survey methods. But there was a slight difference between the two survey methods in morbidity composition. 5. It was concluded that data collected by the interview survey were inclined to be underestimated and this problem can be corrected by a modified self-administered survey.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.3
• /
• pp.529-536
• /
• 2020

This study aims to provide the basic data for coffee intake and health promotion by examining the conditions in which Korean adults consume the most coffee. The study used raw data from the second year of the 7th National Health and Nutrition Examination Survey (2017), and 3,325 subjects who were 19 years of age or older and who were not missing the required values. This number used as the average amount of coffee drank per day in the past year is at least one cup. In order to identify factors that affect coffee intake, the model included general characteristics such as gender, age, household income, education level, occupation, health behaviors such as smoking, drinking, high intensity and moderate intensity exercises, walking, physical activity during work and leisure, sleep time, stress and depression. The results showed that coffee intake was lower among women than men, coffee intake was higher for people 40-64 years than people 20-39 years old, physical occupations rather than non-physical occupations, smokers rather than non-smokers, and for high stress rather than low stress in life. Subjects with these factors are considered to be at risk of excessive caffeine intake from coffee. The risk group of this study should be studied for the effect of excessive consumption of coffee on personal health.