• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.92-106
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• 2004

Elemental dry deposition fluxes were measured using dry deposition plates from March to June 1998 in Seoul, Korea. During this spring sampling period several yellow sand events characterized by long-range transport from China and Mongolia impacted the area. Understanding the impact of yellow-sand events on atmospheric dry deposition is critical to managing the heavy metal levels in the environment in Korea. In this study, the measured flux of a primarily crustal metal, Al and an anthropogenic metal, Pb was used with two hybrid receptor models, potential source contribution function (PSCF) and residence time weighted concentration (RTWC) for locating sources of heavy metals associated with atmospheric dry deposition fluxes during the yellow-sand events in Seoul, Korea. The PSCF using a criterion value of the 75th percentile of the measured dry deposition fluxes and RTWC results using the measured elemental dry deposition fluxes agreed well and consistently showed that there were large potential source areas in the Gobi Desert in China and Mongolia and industrial areas near Tianjin, Tangshan, and Shenyang in China. Major industrial areas of Shenyang, Fushun, and Anshan, the Central China loess plateau, the Gobi Desert, and the Alaskan semi-desert in China were identified to be major source areas for the measured Pb flux in Seoul, Korea. For Al, the main industrial areas of Tangshan, Tianjin and Beijing, the Gobi Desert, the Alashan semi-desert, and the Central China loess plateau were found to be the major source areas. These results indicate that both anthropogenic sources such as industrial areas and natural sources such as deserts contribute to the high dry deposition fluxes of both Pb and Al in Seoul, Korea during yellow-sand events. RTWC resolved several high potential source areas. Modeling results indicated that the long-range transport of Al and Pb from China during yellow-sand events as well as non yellow-sand spring daytimes increased atmospheric dry deposition of heavy metals in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.479-483
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• 2003

Knowledge of N accumulation during the vegetative growth stage of rice (Oryza sativa L.) is useful for determining the need for topdressing fertilizer N at panicle initiation and booting stage. The chlorophyll content showing SPAD threshold values generated by a simple and portable diagnostic instrument, chlorophyll meter, enables implement the measures of greenness and/or relative chlorophyll contents of leaves. Two-year field experiment was conducted to evaluate the possible application of the chlorophyll meter for N diagnosis in transplanted paddy rice. The chlorophyll meter threshold values (SPAD reading) were taken from uppermost fully expanded leaves at 10days interval from 10 days after transplanting. SPAD readings and N contents of rice leaf blade were closely related at the maximum tillering stage. SPAD readings during growth period showed M-shaped distribution, sharply finished to drop at 20 days after heading date. As N fertilizer increased, the SPAD readings increased. The SPAD readings showed more critical and clear difference in immature paddy field than in ordinary paddy field, where the former soil showed higher response to N fertilizer topdressed. Based on the PAD readings for obtaining an optimum sink size bearing the maximum grain yield, N fertilizer to be dressed at the panicle initiation stage is to be adjusted within the SPA$\times$tillers value range 888 in ordinary paddy, and 800 in immature paddy vice. Among the cultivars tested, Huckhyangbyeo, Jinpumbyeo, Ansungbyeo, Sobibyeo, Manpungbyeo, Sangmibyeo, Jinbongbyeo, showed high SPAD values, whereas the cultivars, Nonghobyeo, Saechuchungbyeo, Hwabongbyeo, Mananbyeo, did low values and others intermediate SPAD threshhold values.

• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.283-290
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• 2005

Objectives : The aim of this paper was to examine the relationship between the summertime (June to August) heat index, which quantifies the bioclimatic apparent temperature in sultry weather, and the daily disease-related mortality in Seoul for the period from 1991 to 2000. Methods : The daily maximum (or minimum) summertime heat indices, which show synergetic apparent temperatures, were calculated from the six hourly temperatures and real time humidity data for Seoul from 1991 to 2000. The disease-related daily mortality was extracted with respect to types of disease, age and sex, etc. and compared with the time series of the daily heat indices. Results : The summertime mortality in 1994 exceeded the normal by 626 persons. Specifically, blood circulation-related and cancer-related mortalities increased in 1994 by 29.7% (224 persons) and 15.4% (107 persons), respectively, compared with those in 1993. Elderly persons, those above 65 years, were shown to be highly susceptible to strong heat waves, whereas the other age and sex-based groups showed no significant difference in mortality. In particular, a heat wave episode on the 22nd of July 2004 ($>45^{\circ}C$ daily heat index) resulted in double the normal number of mortalities after a lag time of 3 days. Specifically, blood circulation-related mortalities, such as cerebral infraction, were predominant causes. Overall, a critical mortality threshold was reached when the heat index exceeded approximately $37^{\circ}C$, which corresponds to human body temperature. A linear regression model based on the heat indices above $37^{\circ}C$, with a 3 day lag time, accounted for 63% of the abnormally increased mortality (${\geq}+2$ standard deviations). Conclusions : This study revealed that elderly persons, those over 65 years old, are more vulnerable to mortality due to abnormal heat waves in Seoul, Korea. When the daily maximum heat index exceeds approximately $37^{\circ}C$, blood circulation-related mortality significantly increases. A linear regression model, with respect to lag-time, showed that the heat index based on a human model is a more dependable indicator for the prediction of hot weather-related mortality than the ambient air temperature.

• The Korean Journal of Community Living Science
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• v.15 no.4
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• pp.149-163
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• 2004

The purpose of this study is to present a plan to activate the production and consumption of environmently friendly agricultural products through an analysis on the understanding degree, the level and inclination of consumption, the satisfaction degree of consumption, and the comprehension degree of production and circulation process of the environmently friendly agricultural products. 1 reviewed the literature and did survey In this study. The results are as follows : (1) As a result of an analysis on the understanding degree of the environmently friendly agricultural products, it is shown to get 6.37 points out of 10 and also, there is a difference between age, educational background, and income level. (2) In the case of research on the method to distinguish the environmently friendly agricultural products from others, it is proved that consumers have a strong faith on quality guarantee marks and there is a difference between gender, income level, and consumption period. (3) It is also shown that consumers purchase environmently friendly agricultural products for the family member's health in the survey on the motivation for purchasing them. And also, there is a difference between men and women. (4) The result of the survey on the consumption scale of the environmently friendly agricultural products shows that 94 people(60.3％) spend more than 50％ of their gloss foodstuffs cost purchasing them and 20 people(12.8％) spend 30-50％. (5) In the survey on the amount and the frequency of the purchasing items of the envirounently friendly agricultural products, respondents count livestock products mostly in amount while point out main cereals and a kinds of soy and pastes in frequency. (6) Consumers ask that the price of environmently friendly agricultural products is a little expensive or reasonable and there is no differences between individual groups. (7) In the case of the purchase of foreign environmently friendly agricultural products, there are more people who want to purchase domestic ones than those who want foreign ones. Therefore, it is shown that environmently friendly agricultural products have a counterpower after the market-open to import. (8) As a result of the analysis on the quality of environmently friendly agricultural products, it is proved that they have better quality than general agricultural products and also, it is found out that women feel larger differences than men in quality. (9) In the analysis on the satisfaction degree of the environmently friendly agricultural products, it is proved that respondents trust the safety and nutrition of them whereas they are not satisfied with the external shape of them. (10) It is analyzed that tile conversion of consumer's consciousness is the most critical factor for development of environmently friendly agriculture. (11) The factors to activate the consumption of environmently friendly agricultural products are proved in order of the enlargement of direct transaction, the conversion of consumer's consciousness, the easiness of purchase, activating consumers'unions, and publicity.

• Journal of Environmental Science International
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• v.17 no.4
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• pp.423-437
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• 2008

Until comparatively lately, the annual time series of the $SO_2$ concentration had been shown in a decreasing trend in Ulsan as well as other Korean cities. However, the high concentration of $SO_2$ was frequently found in the specific countermeasure region including the national industrial complex such as Mipo and Onsan in the Ulsan city for the period of $2001{\sim}2004$. There are many conditions that can influence the high concentration of $SO_2$ at monitoring sites in Ulsan, such as: First, annual usage of the fuel including sulfur increased in comparison with the year before in spite of the fuel conversion policy which wants to use low sulfur oil less than 3% and LNG. Second, point source, such as the power plants and the petroleum and chemistry stacks, was the biggest contributor in $SO_2$ emission, as a analyzed result of both the air quality modeling and the stack tole-monitoring system (TMS) data. And third, the air pollutants that occurred in processes of homing and manufacturing of the fuel including sulfur were transported slow into a special monitoring site by accumulating along the frontal area of see-breeze. It was concluded that Ulsan's current environmental policy together with control methods should be changed into the regulation on total amount of emission, including a market-based emission trading with calculating of atmospheric environmental critical loads, for the $SO_2$ reduction like the specific countermeasure for the $O_3$ and PM10 reduction in the Seoul metropolitan area. And this change should be started in the big point sources of $1{\sim}3$ species because they are big contributors of Ulsan's $SO_2$ pollution. Especially it is necessary to revitalize of the self-regulation environmental management. Other control methods for sustaining the $SO_2$ reduction are as follows: maintenance of the fuel conversion policy, reinforcement of the regional stationary source emission standard, and enlargement of the stack TMS.

• Journal of Environmental Health Sciences
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• v.42 no.2
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• pp.92-101
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• 2016

Objectives: Outdoor workers are exposed to thermally stressful work environments. In this study, heat stress indices for harbor workers in summer were calculated to evaluate thermal comfort based on a human heat balance model. These indices are Physiological Subjective Temperature (PST), Dehydration Risk (DhR), and Overheating Risk (OhR) according to respective stage of cargo work in a harbor. In addition, we constructed a forecast system to provide heat stress information. Methods: Thermophysiological indices in this study were calculated using the MENEX model (i.e. the human heat balance model), which used as inputs the meteorological parameters, clothing insulation, and metabolic rate for each stage of cargo work in the harbor of Masan over the course of seven days, including a four-day heat wave. The forecast heat stress information constructed for Masan harbor was based on meteorological data supported by the Dong-Nae Forecast from the KMA (Korea Metrological Administration) and other input parameters. Results: According to higher metabolic rate, thermophysiological indices showed a critical level. In particular, PST was evaluated as reaching the 'Very hot' or 'Hot' level during all seven days, despite the heat occurring over only four. It is important in a regard to consider the work environment conditions (i.e. labor intensity and clothing in harbor). On a webpage, the forecast thermophysiological indices show as infographics to be easily understand. This webpage is comprised of indices for both current conditions and the forecast, with brief guidance. Conclusion: Thermophysiological indices show the risk level to health during a heat wave period. Heat stress information could help to protect the health of harbor workers. Further, this study could extend the applicability of these indices to a variety of outdoor workers in consideration of work environments.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.127-137
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• 1987

This study was conducted to examine the effects of trampling on the changes in soil and vegetation around the trails. The study areas were established both on the trails and in the forested areas located in Ui and Jeongnung valleys at Pukhansan National Park. Soil core sampling, measurements of vegetations and counts of persons visited per hour were done during the period from April 6 to October 9, 1986. The physical properties of soils became better with increasing distances from the trail, and the best conditions were observed in the forested areas. The differences were not significant among the zones within the trailside. More number of individuals and basal area (or coverage) in woody plants were observed in the forested areas than at trailsides. For the herb layer, however, more number of individuals and coverage were shown at the trailside. In the Ui valley, the quantitative measures of herbaceous plants decreased as the bulk density and penetration resistance increased. In the Jeongnung valley, however, only bulk density was negatively related to the quantitative measures. The fact that there were poor relations between soil factors and quantitative measures of herbaceous plants in Jeongnung valley might be influenced by other factors rather than soil compaction. Thus, more research would be needed to understand the critical factors affecting the vegetational changes in recreation areas.

• Korean Journal of Animal Reproduction
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• v.7 no.2
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• pp.57-71
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• 1983

1. Diluted chicken semen can be preserved at 2 to 5$^{\circ}C$ for 24 to 48 hr with resultant fertility of greater than 90% of that of fresh semen. Turkey semen can be preserved at 10 to 15$^{\circ}C$ for 6 to 24 hr and provide economical fertility. 2. Frozen chicken semen has given variable results; a 21 to 93% fertility ranges as compared to 92 to 94% expected with fresh semen. Highest fertility levels obtained with frozen turkey semen intravaginally inseminated have been 61 and 63% using DMSO and glycerol, respectively, as cryoprotectants. 3. The use of glycerol as a cryoprotectant reauires that its concentration in semen be reduced to less than 2% either by dialysis or centrifugation after thawing and before intravaginal insemination if optimal fertility is to be obtained. 4. The temperature at which cryoprotectants are added to semen and the time allowed for equilibration are important for subsequent fertility pre- and post-freezing. 5. The type of container used for packaging the semen, freeze or cooling rates, thaw rates and level of cryoprotectant all interact in affecting cell survival. 6. Plastic freeze straws as a packaging device for semen offers the following advantages: easy to handle, require minimal storage space, offer a wide range of freeze and thaw rates, and insemination can be made directly from them upon thawing. 7. Controlled slow cooling rates of 1 to 8$^{\circ}C$/min have thus far provided the best results for cooling chicken semen throught the transition phase change (liquid to solid) or critical temperature range of ＋5 to -20 or -35$^{\circ}C$. 8. Highest fertilities have been achieved with frozen chicken semen where a slow thaw rate (2。 to 5$^{\circ}C$) has been used regardless of the freeze rate. 9. To maintain a constant high level of fertility throughout a breeding season with frozen semen, a higher absolute number of spermatozoa must be inseminated (2 to 3 times as many) as compared to fresh semen since a, pp.oximately 50% are destroyed during processing and freezing. 10. The quality of semen may vary with season and age of the male. Such changes in sperm quality could be accentuated by storage effects. Thus, the correct number of spermatozoa may very well vary during the course of a breeding period. 11. As to time of insemination, it is best to avoid inseminating chicken hens within 1-2 hr after or 3-5 hr before oviposition; and turkey hens during or 7-10 hr before oviposition. 12. The physiological receptiveness of the oviduct at the time of insemination is a very important biological factor influencing fertility levels throughout the breeding season.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.6-11
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• 1983

The long-term storability of home-made dry sausage and ham in terms of peroxide value and thiobarbituric acid value, the effects of nitrite and NaCl contents on the deterioration of the products and the public acceptance of dry ham were studied. The results of this study are as follows: 1. Because the storability of the dried meat products is mainly affected by the fat rancidity of the fat content, POV of 10 was assumed the critical point of storability. The sample dry sausage used in this experiment has lost its storability within a ripening period of 5 weeks. And dry ham was lost its peculiar relish within 50 days. 2. The variations of the NaCl contents of the dry products were reflected in the ripening process. The correlation coefficient between the variations of the NaCl contents and the decrease in the weight of the dry ham was 0.85. 3. The survey of public taste for dry ham was conducted on 35 college students, who think it a bit tasteful or tasteless account for 66% of the total and those who think it a simple relish account for 60%, thus indicating that the dry ham still remains far away from the dining table.

• Korean Journal of Biological Psychiatry
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• v.12 no.2
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• pp.181-188
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• 2005

Objectives:Hwa-byung has been studied clinically for several years and introduced as Korean Culture- Bound Syndrome. However, the definition and the diagnostic method are not yet clarified, and there has not been any sufficient comparative study on this disease entity. This study was conducted to determine the clinical symptoms and the profile of the neurocognitive functions in Hwa-byung(HB) and Major Depressive Disorder(MDD), and We wish to identify any critical factors that differentiate the disorders. Methods:A total of 102 participants were examined, including 34 participants with MDD, 34 with HB, and 34 healthy controls. The MDD and HB patients were recruited from among inpatients and outpatients at the National Medical Center for the period from May to December of 2004. As a major diagnostic tool of MDD, diagnostic reference of DSM-IV-TR was used and as HB's diagnostic tool, We used computerized neurocognitive function test. Psychiatric symptomatology was evaluated by the Beck Depression Inventory(BDI), and Symptom Checkist-90-Revision(SCL-90-R). Oneway ANOVA, Scheffe post-hoc test and Chi-Squre Tests were used for statistical analysis. Results:The participants in three groups did not differ in terms of age, sex, and education. Assessment of BDI indicated that the MDD group had significantly higher total score than the HB group. MDD and HB groups showed significantly higher total scores on the SCL-90-R in comparison to the controls. The MDD group was found to have significantly more symptoms of depression than the HB group, based on the depression subscale of the SCL-90-R. The computerized neurocognitive function test suggest several results 1) Within the memory domain, it was found that one of the two memory tests in MDD and HB groups were significantly impaired in comparison to the control group. 2) Within the attention domain, it was found that only the MDD group was significantly impaired in comparison to the control group. 3) Within the higher cortical function domain, it was found that significant impairment exist in MDD group and HB group compared to the control group; the severity of impairment was found to be more profound in the MDD group than in the HB group. Conclusion:These results suggest that both HB group and MDD group have significantly decreased neurocognitive function than the control group, and neurocognitive function of the HB group is better than that of the MDD group.