• Journal of Embryo Transfer
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• v.23 no.4
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• pp.257-261
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• 2008

The objective of present study was to investigate the effect of seasons on reproductive performance of Hanwoo and Holstein heifers. Heat stress in summer or cold stress in winter stress to Hanwoo and Holstein heifers may bring reproduction failure, which would pose an important economic loss, even around Daegwallyeong region located in high mountainous area. Seasonal differences in the serum levels of LH, FSH and progesterone ($P_4$) in response to environmental factors (hot and cold) out of 20 pubertal Hanwoo heifers in Daegwallyeong, Gangwon Province and 20 non-lactating Holstein heifers in Chonan city of Republic of Korea at 2-3 years of age were compared. Blood samples for hormonal analysis were from jugular vein after detection of estrus repeatedly over four seasons within four-week intervals (Spring: May to June, Summer: July to August, Autumn: October to November and Winter: January to February). In Hanwoo heifer population, averages of LH and FSH concentration in spring and in summer were greater compared to those in winter (p<0.05). LH or FSH levels tended to be greater (p=0.06) in spring and less (p=0.09) in winter compared to the levels in autumn. Only in summer, cattle seemed to show lower LH or FSH secretion (p<0.05). Similar to the results in Hanwoo heifers, the serum concentrations of LH and FSH in Holstein heifers decreased further by heat stress in summer when P 4 levels were high during luteal phase. The results demonstrate significant effect of summer heat on reproduction of Hanwoo or Holstein heifers. Although parameters indicating the extent of heat stress were not measured in this study, we suggest that serum hormone levels could be considered as successful indicators of summer heat stress condition for Hanwoo and Holstein heifers even under rather cool summer climate.

• 한국해양학회지
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• v.21 no.3
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• pp.156-170
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• 1986

The phytoplankton ecology of estuarine waters was investigated in the Kyeonggi Bay from May 1981 to September 1982 on monthly basis. In this study area, a total of 228 phytoplankton species was identified. Among these taxa, the most dominant species are diatoms in this area. Tychopelagic plankton occupies 40.4% of total species. The percentage of tychopelagic plankton density ranged from 10.2% in September to 92.7% in March of monthly standing crops. From late autumn to early spring, the percentage values are more than 72%. They play an important role from late autumn to early spring in this estuarine plandton community. These tychopelagic planktons are induced from benthic diatoms. Because the bottom shear stresses generated by the tides and winds are stronger than the adhesive and tractive force of benthic diatoms, most of benthic diatoms must be resuspended into tychopelagic suspensions during autumn and winter. Paralia sulcata is the most important tychopelagic plankton as an indicator species of water mixing in the eastern coastal area of Yellow Sea. This species seems to have even broader tolerance to the environmental stress than Skeletonema costalum, and tends to fill the gaps in winter, when the phytoplandton is relatively unsuccessful. Skeletonema costatum and Chaetoceros debilis are dominant in other seasons. Typical blooms of phytoplankton occur in spring and early autumn, The first bloom is started by Skeletonema costatum in early May, second peak is formed by various diatom population in September.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.47-60
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• 2020

To assess the characteristics of phytoplankton community structures related to environmental factors, seasonal surveys were conducted in the vicinity of Dokdo. In 2019, phytoplankton of four phyla and 69 species were observed. During winter, unidentified nanoflagellates dominated, with an average of 3.19×10⁴ cells L^-1. In spring, unidentified nanoflagellates occupied about 50% of the composition and a variety of dinoflagellates appeared. The summer phytoplankton population showed very low abundance. In autumn, various species of Chaetoceros appeared, along with diatoms, such as Bacteriastrum spp., Guinardia striata, and Pseudo-nitzschia spp. In addition, tropical species Amphisolenia sp. and Ornithocercus sp. were observed in both 2018 and 2019. The diversity was high in the summer of 2018 and the winter of 2019 and the characteristics of each index varied. Cluster analysis was divided into four groups according to species and population characteristics regardless of the season. The stratification of spring was particularly weak. In the autumn of 2018, the water mass was stabilized in the same way as in the summer, which is considered a suitable condition for phytoplankton growth. However, in 2019, the water masses were mixed, resulting in a low population. In a phytoplankton comparison, the dominant group showed seasonal differences, except for summer when the population was low, and the difference was most pronounced in autumn. Therefore, the waters surrounding Dokdo have different environmental and ecological characteristics from the East Sea, but the seasonal characteristics of each year are considered to be different depending on the topography, various currents, the island effect, and other factors.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.281-286
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• 2006

In case of Korea, immovable property like location, land prise or investment value is more highly estimated than quality of life of residents for performance and value of apartment house, because of limited land area or high density of population. But the high level of life has recently caused the increasing demand in better life. As there is no cases to provide the house in bulk due to the housing market condition, it is necessary to evaluate performance and value of structure, disaster prevention safety, habitability, antiquated condition of building and equipment, maintenance condition and so on that has importantly influence on resident's life quality. So, this study aims to understand the actual condition of environmental performance for the present apartment by comparing the designated apartment, which is ready to have completed in Daegu, with the mixed use residential building, which gained the best grade for green building certification system. Also by analyzing and evaluating a right to enjoy sunshine, floor impact noise etc. and indoor air quality.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.159-162
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• 2006

The purpose of this study is to set up systematically housing adaptation items for the aged family. Housing adaptation items are classified by universal design principles. Also, this paper suggest to basic data for setting up various ranges according to each elderly people's conditions, adapting for elderly housing. Recently, in relation to the growing awareness of the ageing population, the necessity of policies for "aging in place" was emphasized by government. This paper is focused on the policy of elderly housings' adaptation for making housing for a lifetime. This new adaptation items for the elderly housing lead to the revitalization of policy ensuring housing in stock at the local authority level. In this paper, adaptation items were created after analyzing indices highlighted by previous studies related to evaluation items, design-guidelines for safety plans, designing elderly housing. The scope of adaptation items was limited to the indoor spaces of apartment due to the considerable increase of in-house accidents. To sum up, this study is aimed to set up adaptation items and then, to present the basic scheme for several users offering various ranges

• The Korean Journal of Ecology
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• v.19 no.5
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• pp.393-402
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• 1996

Density fluctuations of soil microarthropods at the Piagol, Mt. Chiri was assessed on the basis of 113, 096 individuals collected from March 1993 to February 1994. Of 6 classes, and 18 orders, the Arachnida and Insecta were the most numerous members with abundance of 51.4% and 46.3%, respectively. The mean density of the Acari was $13, 310/m^2$ of microarthropods. The Acari were abundant in autumn and less found in winter and the density fluctuation of the Collembola followed a similar trend. The vertical distribution of the mesofauna revealed from the soil samples taken from the surface to 5 and from 5 to 10 cm in depths was as follows. In 5~10 cm layer. Collembola was numerous with abundance of 54.7%, followed by 40.1% fo Acari and the soil microarthropods reached the highest density peak in spring, while the lowest in winter. Populations concentrated in the 0~5 cm layer as much as 62.2% throughtout the season and 82.4% throughtout the altitudes. The Acari / Collembola (A/C) ratio in the 0~5 cm layer was higher than that in the 5~10 cm.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.33-36
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• 2009

Korea is the 3rd highest country in population density of the world,furthermore, 1/5 of Korean lives in Seoul with only 0.0% tiny area size. It explains the high-rise apartment has diffused so fast. Regardless of its height, almost all apartments have been planned in a very uniform way, ignoring the possibilities of vertical community and commercial culture. Since considerable number of residents have within building, ways to improve the community and commercial culture need to be explored. One major way to do is providing community space where residents are expected to use in a natural way. The purpose of this research is to identify preferred location of community space in each apartment building. Web guesting survey was used as main methodology. 83 data were collected during mid October, 2009. As results, lobby at the first floor was most favorably selected by super high-rise apartment residents due to convenience, accessibility.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.11-16
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• 2009

Public rental apartment has suffered social exclusion problem, stemmed from its closed planing for a very specific range of the disadvantaged population. Thereby, it has been recognized as a disliked residential facility. To alleviate this problem, various approaches have been tried such as ownership-tenant mixture, and different unit size mixture. The purpose of this study is to grasp the expected social relation among neighboring residents according to socially integrative planing elements such as ownership, unit size and family life cycle match. Thirty eight graduate students in architecture and housing field responded to the questionnaire which was specifically made to identify relations of 28 neighboring situations based on $2{\times}2{\times}2$ variable composition. Frequency, percentage and MDS(multidimensional scaling) were used to analyze data. As a result, the order of preferred matchy were identified. The match between rental/small/children group and ownership/middle/children group was turned out to be the most desirable while the match between rental/small/children family group and rental/small/elderly group was found the least desirable. Spatial representations of the relationships among 8 household types were delineated. In conclusion, the definite patterns of the favorable and unfavorable match were found. This result is expected to be used as a reference in developing a strategic match to promote the rental apartments social integration in Korea.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.82-85
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• 2009

Amongst society's transitional presuppositions towards the future, an aging population is the most significant matter. Korea has entered the aging society in 2000 and will face the aged society by 2018, which is the fastest time that takes from the aging society to the aged society in the world. Korea requires immediate attention to devise a countermove. U.S entered aging society in 1942 since then have developed various types of elderly housing. Recently, university-affiliated CCRC became an attractive alternative. Therefore, it is necessary to study a successful case of elderly housing. This study aims to explore the key features of a university-affiliated CCRC as an alternative socially integrated aging friendly community. Oak Hammock at the University of Florida was selected for this research as a successful case. The method of this is field visit case study. The study finds that University-affiliated CCRC has a lot of benefits for both university and CCRC. Oak Hammock members can access university's facilities and university provides a life-long learning experience and other programs. Oak Hammock provides internship, volunteer and parttime job opportunities and offer advice to students as a mentor. This study is expected to provide a implication in developing elderly housing of Korea.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2011.04a
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• pp.116-120
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• 2011

With population growth and quality of life improvement, household energy use also has increased. Under this circumstances, consumers are increasingly required to seek for efficient ways of energy saving. However, precedent studies have largely overlooked energy consumers' consumption behavior, and particularly little research has been conducted on energy consumption or saving patterns of residents living in apartments, which account for over 50% of the Korean housing market. Therefore, this study examined apartment residents' energy use behavior according to apartment residents' characteristics in order to efficient energy use and management. To this examination, survey was conducted of housewives living in apartments in Busan, and 403 data were analyzed by the SPSS WIN 12.0 program. With respect to their energy behavior according to characteristics of subjects, it was different depending on income, housing size, age, the length of residence, and the education standard. When higher income group and larger housing size group, residents were not doing 'passive saving' and 'comfort oriented.' When younger, they were 'comfort oriented.' When well-educated, they were 'comfort oriented.' Also, with regard to the length of residence, significant difference was found. The results of this study can be utilized as effective guidelines in efficient management, policy making, and education method reflecting energy use behavior of energy users.