• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.164-180
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• 1991

For the purpose of contributing to the promotion of health of the employees working at the same kind of department store or similar type of business and the people utilizing them and preparing the basic data for the establishment of mangagement measure by assessing the level of air pollusion at indoor and outodoor of four department store among the distribution service business in Pusan area, authors measured the concentration of sulfur dioxide, nitrogen dioxide, formaldehyde and total suspanded particle according to the measuring height of variable at indoor and outodoor from Aug. 1990. to sep. an. d Jan, 1991 to Feb.: for each two months in summer and winter, and studied by dividing the variable factor into atmospheric factor (temperature, humidity and air velociy) The results are as follows ; 1. The mean concentration of air pollutants at indoor to total subjects was nitrogen dioxide 31.1ppb, sulfur dioxide 51.7ppb, formaldehyde 162.lppb and total suspanded particle $67.7{\mu}g/m^3$, and it was higher in winter than in summer (P>0.05) 2. The mean concentration of formaldehyde to total subjects was higher indoors than outdoors (P<0.001), in case of nitrogen dioxide there was no significant difference and sulfur dioxide and total suspanded particle were higher outdoors than indoors (P<0.05) 3. The concentration of nitrogen dioxide and sulfur dioxide proved to be a adverse correlation, reducing with height. 4. According to the result questioned about the exposure concentration of pollutant and the general symptom caused by the pollutant, nitorgen dioxide and symptom proved to be a positive correlation (P<0.09).

• Journal of Embryo Transfer
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• v.15 no.1
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• pp.57-65
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• 2000

The objective of this study was to apply the multiple ovulation and embryo transfer (MOET) program practically in dairy herds. Forty five superior Holstein cows ranked in 5% according to Type-Production Index(TPI) in Korea were selected as donors. The donors were superovulated with pFSH and the embryos collected from donors were frozen and preserved. The preserved embryos and frozen Holstein embryo imported from foreign country were thawed and transferred to recipients. The results obtained were as follows; 1. The total number of ova and freezable embryos collected per donor was 6.5 and 2.8, respectively. 2. The freezable embryos were obtained more(p<0.05) when the body condition score (BCS) of donors was in range of 2.50∼3.25(4.1) than in range of 3.50∼4.00(1.9), while the total number of ova was not changed. 3. The season affected on the collected number of freezable embryos(6.1 in winter, 4.5 in fall, 1.1∼1.5 in spring and summer, P<0.05), and the total number of obtained ova were more in winter than in other seasons(P<0.05). 4. Embryos were transferred to 343 recipients and 152 cows were confirmed pregnant(44.3%). 5. The higher pregnancy was obtained (P<0.05) when embryos were transferred in summer(53.3%) than in fall(36.0%), while the pregnancy rate was not affected by the origin and developmental stage of embryos, and the parity, BCS and estrus induction of recipients. From these results, the pregnancy rate was considered to be acceptable for the embryo transfer with domestic or imported Holstein embryos, however embryo production from superior Holstein donors was unsatisfactory for application of MOET scheme.

• Fashion & Textile Research Journal
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• v.12 no.5
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• pp.676-682
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• 2010

Superior hydrophilic properties will allow varieties of polyester(PET) fiber materials, fabrics and industrial materials a broader scope of use. The purpose of this study was to investigate the effect of water-absorbent softener treatment on the end-use properties and the hand of polyester knitted fabrics. Two different fabrics were knitted for the summer ladies' outwear; PET jersey and PET mesh. Variables were softner treatment and stitch type(jersey and mesh). Mechanical properties of the fabric samples were measured by KES-FB system. From these, primary hand values(HV) were evaluated by the conversion equation (KW-403-KTU) and the total hand value(T.H.V.) was calculated according to the KN-304 Summer. Both water-absorbent softner treatment and stitch types affected mechanical properties and hand values of PET fabrics. Mesh were thicker than single jersey stitch. As they became thicker, tensile, shear, and compressional energy increased. It appeared that coefficient of friction of mesh stitch was larger than that of single jersey stitch. The coefficient of friction and the mean deviation of surface roughness were decreased by softener treatment. After softner treatment KOSHI and SHARI of the both PET jersey and PET mesh decreased. However, FUKURAMI values of PET jersey increased and that of PET mesh decreased. The T.H.V. of the treated PET jersey was lower than that of the untreated one, while the T.H.V. of the treated PET mesh was higher than that of the untreated one. Overall T.H.V. of the single jersey was better than that of the mesh before and after softner treatment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.1
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• pp.1-5
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• 1991

Tall fescue(Festuca amndinacea Schreb.) is a productive pasture grass that is widely adapted to the soil and climate of Korea. It is regarded, however, as relatively low in palatability and nutritive value. On the other hand, Italian ryegrass(lo1ium rnultz$om Lam.) is highly nutritious and palatable, but is essentially weak in cold tolerance. Numerous investigators have succeeded in producing hybrids between Lolium spp. and Festuca spp. but no improved varieties have resulted. Therefore, intergeneric hybridization of Italian ryegrass with tall fescue is employed in 1984 to improve the adaptive and cold resistance quality of Italian ryegrass. In the mean time, F1-hybrid plants obtained by crossing Italian ryegrass x tall fescue were observed in open field. The results are summarized as follows: 1. Leaf-size and silica cell hair were intermediate between the types of parents but the shape of auricle tended to show Italian ryegrass and auricle-cilia to show tall fescue. 2. Roots of $F_1$-hybrid plants were mainly distributed at top soil and did not produced florescence material. 3. Head type of hybrids was intermediate between the types of parents but ray length was somewhat less than the length of tall fescue ray. Typical Italian ryegrass or tall fescue-like phenotypes were not observed. 4. Anthers of $F_1$-hybrid plants were formed but pollen were not formed. Even though pollen were formed, they were all empty. 5. Hybrid plants were more winterhardy and summer persistency than Italian ryegrass. They showed a equivalent growth to Italian ryegrass in spring and to tall fescue in summer. 6. Chromosome of $F_1$-hybrids was allopolyploid(2n=4~=28) and all $F_1$-hybrid plants were sterile.

• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.75-83
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• 2014

Heat loss through windows and doors occupies 20 to 45% of the total heat loss in building. It accounts for a large proportion of the total heat loss in building. In order to suppress the amount of heat flow through the windows and doors were considered actions such as reinforcement of insulation performance of window, adoption of low-e glass, and installation of solar heat shading device. The Purpose of this study is to compare solar heat shading performances of 3 types of internal blinds in the summer. In order to verify the solar heat shading performances of the blinds, a roll blind, blind A(Venetian blind) and blind B(Daylight guiding venetian blind)were installed in the four rooms with the same environmental conditions. As a result of the experiment, the blind B, blind A, roll blind showed an excellent performance in that order. Its because the blind B is made of aluminum materials coated with special paints on surface. It doesn't converted to long wave by short wave light. and it is reflected to short wave to outside.

• Journal of Environmental Science International
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• v.23 no.4
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• pp.637-647
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• 2014

Quantitative assessment of groundwater level change under extreme event is important since groundwater system is directly affected by drought. Substantially, groundwater level fluctuation reveals to be delayed from several hours to few months after raining according to the aquifer characteristics. Groundwater system in Jeju Island would be also affected by drought and almost all regions were suffered from a severe drought during summer season (July to September) in 2013. To estimate the effect of precipitation to groundwater system, monthly mean groundwater levels in 2013 compared to those in the past from 48 monitoring wells belong to be largely affected by rainfall(Dr) over Jeju Island were analyzed. Mean groundwater levels during summer season recorded 100 mm lowered of precipitation compared to the past 30 years became decreased to range from 2.63 m to 5.42 m in southern region compared to the past and continued to December. These decreasing trends are also found in western(from -1.21 m to -4.06 m), eastern(-0.91 m to -3.24 m), and northern region(from 0.58 m to -4.02 m), respectively. Moreover, the response of groundwater level from drought turned out to be -3.80 m in August after delaying about one month. Therefore, severe drought in 2013 played an important role on groundwater system in Jeju Island and the effect of drought for groundwater level fluctuation was higher in southern region than other ones according to the regional difference of precipitation decrease.

• Journal of Embryo Transfer
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• v.30 no.1
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• pp.59-64
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• 2015

Intensive genetic selection has resulted in modern dairy cow with very high milk yields but reduced fertility, due mainly to an increase in reproductive disorders. The study was conducted to estimate the proportion of reproductive disorders among dairy cattle. The factors analyzed were; milk yield, cow parity, periparturient disorders, and reproductive status. The result of this study showed the incidence of reproductive disorders in high yielding dairy cows was prevalent. Repeat breeding was the major postpartum reproductive problem comprising (42.3%) of the samples. Higher reproductive disorders were also associated with lower parity. These disorders subsequently reduced reproductive performance by prolonged intervals from calving to first artificial insemination and from calving to pregnancy. Abnormalities in the reproductive system such as repeat breeder, silent heat, anestrous and ovarian cysts, as well as lower fertility have been recorded during the summer months (June to August). In conclusion, the study revealed that incidence of repeat breeder is mostly prevalent in dairy cows. Moreover, the incidence of reproductive disorders was higher in summer season and hence appropriate preventive and or therapeutic measures as per the type of abnormalities need to be undertaken.

• Journal of the Korean Geotechnical Society
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• v.23 no.4
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• pp.47-58
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• 2007

The usage of Integral abutment bridges has been increased worldwide because of reducing bridge maintenance costs and resisting seismic loads. Although these attributes make the integral abutment bridge an increasingly popular choice, back-abutment interaction issues remain unresolved. Hence, the earth pressure behavior of an integral abutment bridge having 90 m long PSC beam bridge for the first time in Korea was analyzed by conducting long term monitoring in this study. Based on this study, the results were as follows; the ratio of maximum passive movement to the abutment height (H) of 0.0027 and the maximum passive earth pressure coefficient of 4.8 were developed at 0.82H from the bottom of the abutment during summer season. During winter season, the ratio of maximum active movement to H of 0.0011 and the maximum active earth pressure coefficient of 0.7 were developed at the same location as in summer season. The new earth pressure distributions having a trapezoid type were proposed based on this study.

• Journal of Ecology and Environment
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• v.47 no.3
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• pp.134-145
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• 2023

Background: The flowering and fruiting periods play an important role in biological processes. The deciduous dipterocarp forest is an important forest type in Thailand, however the phenological studies are still limited, particularly in different plant life forms. Thus, the present study focused on the flowering and fruiting phenology of herbs, climbers, shrubs, and trees in the deciduous dipterocarp forest at Lampang province of Northern Thailand. Field visits were made to record plant life forms and observe reproductive phenological events at monthly intervals from November 2018 to October 2019 and September to December 2020. Results: The phenological observations were based on 126 species of 45 families and 102 genera. Flowering and fruiting periods showed similar patterns in herbaceous plants, climbers, and shrubs. Most of these species produced flowers and fruits from the end of the rainy season (October) to the winter season (November-January). Whereas most of flowering and fruiting trees were found from the summer season (March-April) to the beginning of the rainy season (May-June). Most of the dry-fruited species occurred during the dry period (winter and summer seasons), while the majority of fleshy-fruited species dominated in the wet period (rainy season). The statistical analysis supported the phenological patterns of flowering and fruiting in the present study. There were significant negative correlations between the number of flowering and fruiting species and temperature. The number of flowering and fruiting species is significantly impacted by the interaction between seasons and plant life forms. Conclusions: Plant life form seems to be the important factor that affects the different phenological patterns in the studied plants. The abiotic and biotic factors play major roles in reproductive phenology. However, long-term study and in-depth phenological observations are necessary for better understanding.

• Journal of Environmental Science International
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• v.33 no.1
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• pp.75-85
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• 2024

An intensive observing period (IOP) of heatwaves in the urban region of Seoul in the summer of 2023 was carried out to understand the changes in air temperature and road temperature induced by environmental conditions. The temperature observed at eight points with different urban environmental conditions was compared with the temperature by the KMA/AWS to analyze the characteristics of change in air temperature by height and the change in road temperature according to environmental conditions and road sprinkler. The comparison of the average temperature observed in different urban environmental conditions with the temperature observed at KMA/AWS showed that the air temperature in asphalt and open space sites was 0.7 to 2.3℃ higher and that the one in bus stops was 0.9 to 2.3℃ higher. In terms of temperature deviations depending on residential type, the temperature in highly populated areas was about 0.1 to 0.8℃ higher than that of apartment complexes. In addition, regardless of the size of a park, the temperature in the park was lower than the temperature in dense housing areas and apartment complexes. In asphalt and residential areas, the road temperature was higher than the temperature at a height of 150 cm, Conversely, road temperature was lower than air temperature in a shaded shelter and large park. In addition, after spraying a surface road, the road temperature immediately dropped by about 3 to 4℃; however, after about 20 minutes, it rose again to the previous road temperature. This change in road temperature appeared only for the temperature of 30 cm height.