• Journal of Korean Society of Transportation
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• v.30 no.3
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• pp.71-82
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• 2012

This study analyzed factors affecting daily travel times at each stage of commuters' life cycle. In this study, travel times were dealt with in the context of trip chain. That is, the travel time was defined as the total amount of time commuters had spent to move for daily activities from leaving to coming back home. A commuter's life cycle was divided into 6 stages on a basis of both householder's age and family type: i.e., the unmarried youth period, the family forming period, the children education period, the children youth period, the children independence period, and the aged period. Variables such as commuting times, home-based trip cycle recurrences, and the number of stops differed for each stage of life cycle, the latter of which represents how many places a commuter dropped by during a trip cycle. Several factors were found to affect commuting times at each stage of life cycle as a result of applying a Cox proportional hazard model. The empirical study was conducted using 2010' household travel survey data collected from Gyeonggi-do.

• Korean Journal of Health Education and Promotion
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• v.27 no.1
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• pp.21-34
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• 2010

Objectives: The objective of this study was to investigate risk factors for falls in the elderly by life-cycle. Methods: This study used the data on 435 male and female elderly generated from a survey taken at 21 Welfare Centers for the Elderly in Seoul. The incidence of demographic characteristics, physical changes brought about with ageing, health-related behavior, chronic diseases, and environmental characteristics on falls in the elderly was analyzed. Hierarchical Logistic Regression analysis was also conducted to investigate the incidence by life-cycle (early-mid-late stage) and the results were used for predicting falls. Results: The incidence of risk factors on falls varied across life-cycle. Among the elderly in the early (ages from 65 through 74), marital status, the existence of a companion, the quality of sleep, the chronic diseases, and the condition of the bathroom floor were found to be related to falls. Among those in the mid-stage (ages from 75 through 84), sex, marital status, the existence of a companion, hearing capacity, sense of balancing, chronic diseases, the exclusive use of rooms, and the side bar with bath tub were found to affect falls. Finally, for the elderly in their late stage (85 years of age and older), drinking and vision were found to be related to falls. Conclusion: The incidence of risk factors on falls was found to vary according the stage in the elderly. A key implication of this finding is that falls prevention programs and interventions must be catered to specific age sub-groups.

• Reproductive and Developmental Biology
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• v.35 no.4
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• pp.463-468
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• 2011

This study investigated the changes of plasminogen activators (PAs) activity, expression and localization of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA) during the estrous cycle in pigs. Estrous cycle was sorted into three group by pre-ovulation (Pre-Ov), post-ovulation (Post-Ov) and early to mid-luteal stages (Early to mid-L). Analysis for immunohistochemistry was confirmed by location of tPA and uPA. Porcine uterus tissue was cut into $1{\times}1$ cm squares, and were incubated in DMEM/F-12 medium for 1 h at $38^{\circ}C$, 5% $CO_2$ for measurement of PA activity. Western blotting was implemented for measurement of PA quantity. In results, the blood vessels and secretory glands were increased in Post-Ov stage than Pre-Ov and Early to mid-L stages. The tPA and uPA was located mainly within lumen of blood vessels and secretory glands. The PA activity in Post-Ov ($0.99{\pm}0.03$) stage were significantly (p<0.01) higher than Pre-Ov stage ($0.51{\pm}0.03$) and Early to mid-L stage ($0.21{\pm}0.04$). Expression of PAs were significantly (p<0.05) higher in Early to mid-L stage than other stages. These results indicate that PAs activity and expression may change in uterus tissue during the estrous cycle in pigs.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.168-176
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• 2014

The enterprise life cycle derived from the product life cycle consists of introduction, growth, maturity and decline. The enterprise tries to reach the growth stage early and stay at the maturity stage stably through expanding its businesses and investing for the new technology. The public enterprise is not different but its life cycle is more prone to be affected by the national development and policy. A typical example can be found in the case of the quasi market SOC public enterprise which spends massive amount of fund to provide social infrastructure. After the fulfillment of its mandated mission it is exposed to the pressure of a merger or a closure usually because large portion of the debt is directly linked to the national financial stability and credit ratings. This research is focused on the variables that influence the life cycle of the quasi market SOC public Enterprise for its future competitiveness is in connection with its normalization, advancement and rationalization. In this respect, categorical variables system centering on public characteristics and profitability drew eight categorical variables such as policy outcomes, public benefit, finance and business values etc.

• Atmosphere
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• v.21 no.3
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• pp.273-284
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• 2011

This study investigates the characteristics of satellite brightness temperature (TB) and rainfall intensity over the life cycle of convective cells. The convective cells in the three event cases are detected and tracked from the growth stage to the dissipation stage using the half-hourly infrared (IR) images. For each IR images the values of minimum, mean, and variance for the convective cell's TBs and the sizes of convective cells are calculated and also the relationship between TB and rainfall intensity are investigated, which is obtained using the pixel values of satellite TB and the ground rainfall intensity measured by AWS (Automatic Weather Station). At the growth stage of the convective cells, the TB's variance and cloud size consistently increased, whereas TB's minimum and mean consistently decreased. At this stage the empirical relationships between TB and rainfall intensity are statistically significant and their slopes (intercepts) in absolute values are relatively large (small) compared to those at the dissipation stage. At the dissipation stage of the convective cells, the variability of TB distributions shows the opposite trend. The statistical significance of the empirical relationships are relatively weak, but their slopes (intercepts) vary over life cycle. These results indicate that satellite IR images can provide valuable information in identifying the convective cell's maturity stage and in the growth stage, they may be used in providing considerably accurate rainfall estimates.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.2
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• pp.280-291
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• 2002

This study was to apply FLC(Fashion Life Cycle) concept with extended PLC(Product Life Cycle) theory of marketing for a basis. This article was particularly analyzed relations between demographic variables and fashion lifestyle toward consumer's behavior at decline stage of FLC empirical study was to target women's formal dress. Data were collected from the adult females residing in Youngnam district. Sampling were peformed pretest and main survey. Total 386pcs of answers were used for final analysis. The results of analysis were as follows. First, Hypothesis 1 & 4 were showed meaningful differences between fashion lifestyle patterns and consumer's behavior at decline stage of FLC according to demographic characteristics. Second, Hypothesis 2 also was adopted meaningful differences of consumer's hoarding behavior at decline stage of FLC in accordance with fashion lifestyle patterns. Third, Hypothesis 3 of fashion lifestyle patterns which has related consumer's recycling behavior at decline stage of FLC was rejected. In conclusion, This article discusses implication of fashion marketing strategies and summaries..

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.704-711
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• 2005

Recently Life Cycle Cost Analysis for civil infrastructures such as pavements, bridges, and dams has been emphasized However, so far, there are few systems available for life cycle cost analysis of bridges at design stage. Therefore, the objective of this paper is to develop a user-friendly life-cycle cost analysis system for LCC-effective optimal design decision making at design stage. The program is based on the proposed LCC model, formulation, analysis modules and systematic procedure that suit Korean construction conditions. It is expected that the developed system can be effectively utilized for more LCC-effective design of bridges. It is applied to an actual bridge design project in order to demonstrate its effectiveness and applicability.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.27-31
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• 1988

Biosynthesis and processing of cytoplasmic mRNA from heterogenous nuclear RNA (hn-RNA) in Aspergillus phoenicis were studied by $^{3}H$-uridine labeling and synchronous culture techniques during their life cycle. Incorporations of $^{3}H$-uridine into hn-RNA and mRNA were most rapid in vesicle-phialide fromation stage and diminished in hyphal growth stage. The processing of cytoplasmic mRNA from hn-RNA was proceeded more rapidly in hyphal growth and conidiophore formation stages than in conidia and vesicle-phialide formation stages. The specific radioactivities of hn-RNA and mRNA were very high in vesicle-phialide formation stage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.205-208
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• 2009

The purpose of this study is to apply the process model of the pre-design stage to CPLM(Construction Project Life-cycle Management). Life-cycle consists of 4 stage; Pre-design, Design, Construction, Maintenance. Each stage has organic relations between front and rear stage. Therefore it is important to manage and use the information data of each stage. But these data are not carried to the next stage smoothly, especially at the pre-design stage. It is even vague to define the process of the pre-design stage. To carry and share the information well, this study defines Pre-design stage process and CPLM at first, VA-Cityplanner which is the development system of the pre-design process model is applied to CPLM for the smooth current of the data between participants.

• Journal of the Korean housing association
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• v.27 no.1
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• pp.1-11
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• 2016

Based on residents' survey data in Seoul, this study attempts to empirically answer to four research questions regarding neighborhood relations (NR) which are necessary for community building: How important NR is compared to other social relations, what factors establish NR, how large NR's geographical extent is, and what are major meeting places among neighbors. A series of statistical analyses demonstrates that characteristics of NR vary greatly by family life cycle. In the stage of couple without child, NR has no significant meaning. NR becomes important from the stage of child care, and it is formed through the medium of children, particularly children's schools in the stage of child of elementary school as well as secondary schools. As the result, NR's geographical boundary extends beyond residential block or multi-family housing (apartment) estate while cafe and restaurant serve as dominant meeting places in these life cycle stages. On the contrary, after children are married and leave home, casual encounters resulted from spatial proximity become an important cause of NR. Likewise neighbors' geographical distribution is relatively concentrated within residential block or apartment estate, while community facilities play a role of meeting places as originally planned and designed.