• Journal of Preventive Medicine and Public Health
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• v.39 no.1
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• pp.74-80
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• 2006

Objectives: The purpose of this study is to examine the factors affecting the rate and duration of breastfeeding. Methods: We analyzed the data from the year 2000 Korea National Fertility Survey that was collected through direct interviews. In particular, the mothers who delivered their last child and the child was under 1 year of age from January 1998 to June 2000 (N=1,066) were analyzed via a logistic model to assess the factors affecting the breastfeeding rate. Among the study subjects, those who had initiated breastfeeding (N=740) were analyzed through Cox's proportional hazard model to evaluate the factors affecting the duration of breastfeeding. Results: The multivariate logistic model showed that the delivery type and the baby's birth-weight have a statistically significant influence on the breastfeeding rate. Women who delivered their babies through Cesarean section were less likely than others to breastfeed. In contrast, the women whose babies weighed 2.5Kg or more were more likely than others to breastfeed. The results obtained from the survival analysis are as follows: the higher the mother's education level, the shorter is the breastfeeding duration. The mother's work status played a significant role in the early termination of breastfeeding. Women aged 35 or older showed a longer breastfeeding duration than the younger age groups, whereas the maternal age was not a significant factor in affecting whether or not a mother would breastfeed. Conclusions: Reducing the cases of operative delivery (Cesarean section) and low weight births, enlightening young and highly educated women on breastfeeding and improving the environment for breastfeeding on the job are important strategies to encourage women to breastfeed.

• Journal of Broadcast Engineering
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• v.4 no.1
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• pp.44-58
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• 1999

In this paper, a rate-distortion based image segmentation algorithm is presented using a recursive merging with region adjacency graph (RAG). In the method, the dissimilarity between a pair of adjacent regions is represented as a Lagrangian cost function considered in rate-distortion sense. Lagrangian multiplier is estimated in each merging step, a pair of adjacent regions whose cost is minimal is searched and then the pair of regions are merged into a new region. The merging step is recursively performed until some termination criterion is reached. The proposed method thus is suitable for region-based coding or segmented-based coding. Experiment results for 256x256 Lena show that segmented-based coding using the proposed method yields PSNR improvement of about 2.5 - 3.5 dB. 0.8 -1.0 dB. 0.3 -0.6 dB over mean-difference-based method. distortion-based method, and JPEG, respectively.

• Journal of Broadcast Engineering
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• v.17 no.5
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• pp.765-780
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• 2012

In this paper, we propose a fast mode decision method that determines the coding unit depth for enhancement layers to improve an encoding speed of a scalable video encoder based on HEVC. To decide the coding unit depth of the enhancement layer, firstly, the coding unit depth of the corresponded coding unit in the basement layer is employed. At this stage, the final CU depth is decided by calculating the rate-distortion costs of one lower depth to one upper depth of the referenced depth. The proposed method can reduce a computational load since it does not calculate the rate-distortion costs for all the depths of a target CU. We found that the proposed algorithm decreases encoding complexity of 26% with approximately 1.4% bit increment, compared with the simulcast encoder of the HM 4.0.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.80-83
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• 2008

The characteristics of the spread of a forest fire are generally related to the attributes of combustibles, geographical features, and meteorological conditions, such as wind conditions. The most common methodology used to create a prediction model for the spread of forest fires, based on the numerical analysis of the development stages of a forest fire, is an analysis of heat energy transmission by the stage of heat transmission. When a forest fire breaks out, the analysis of the transmission velocity of heat energy is quantifiable by the spread velocity of flame movement through a physical and chemical analysis at every stage of the fire development from flame production and heat transmission to its termination. In this study, the formula used for the 1-dimensional surface forest fire behavior prediction model, derived from a numerical analysis of the surface flame spread rate of solid combustibles, is introduced. The formula for the 1-dimensional surface forest fire behavior prediction model is the estimated equation of the flame spread velocity, depending on the condition of wind velocity on the ground. Experimental and theoretical equations on flame duration, flame height, flame temperature, ignition temperature of surface fuels, etc., has been applied to the device of this formula. As a result of a comparison between the ROS(rate of spread) from this formula and ROSs from various equations of other models or experimental values, a trend suggesting an increasing curved line of the exponent function under 3m/s or less wind velocity condition was identified. As a result of a comparison between experimental values and numerically analyzed values for fallen pine tree leaves, the flame spread velocity reveals has a error of less than 20%.

• Journal of Genetic Medicine
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• v.9 no.1
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• pp.22-24
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• 2012

Purpose: The aim of this study was to asses the fetal loss rate after mid-trimester amniocentesis. Materials and Methods: This was a retrospective cohort study including singleton pregnant women who underwent mid-trimester amniocentesis at Cheil General Hospital from January 2008 through December 2010. The procedure-related fetal loss was defined as miscarriage within 2 weeks after amniocentesis. We evaluated the fetal loss rate within 2 weeks after amniocentesis and fetal loss rate before 24 gestational weeks. Results: During the study period, a total of 4,356 singleton pregnant women underwent mid-trimester amniocentesis. A total of Five hundred ninety six women were excluded owing to follow up loss and termination of pregnancy due to abnormal karyotype or major anomaly. At our institute, the fetal loss rate within 2 weeks was 0.1% and before 24 gestational weeks was 0.3% after amniocentesis. Conclusion: The fetal loss rate after mid-trimester amniocentesis in our study is lower than previously reported rate. We suggest that amniocentesis is a safe procedure.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.648-654
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• 2010

Request operations and release operations occur repeatedly in resource allocation systems. The process requesting a resource acquires one by any priority-based mechanism, and returns the resource after some periods. In this system, resource failures lead to delay of resource allocation, or to termination of process holding the failed resource. To analyze this process effectively, this paper designs a probabilistic ACSR, a process algebra that extends ACSR with the probabilistic choice operation. The ability to express/analyze both request-release rates and failure-recovery rates is illustrated using probabilistic ACSR.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.361-361
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• 2009

KEPCO High Temperature Superconducting (HTS) cable system rated with $3\Phi$, 22.9kV, 1250A was laid in 2006, and the long term test is in progress. The HTS cable system with the cooling system has been operated below cryogenic temperature. That environment exposes the system to the thermo-mechanical stress due to the significant temperature difference, and the cooling system has moving parts for the forced circulation of the coolant. Therefore the HTS cable system experiences thermal fatigue and moving part such as liquid nitrogen pump need a regular replacement every 5000 hours Building the assessment criterion, the maintenance procedure was established and regular preventive maintenance was done; improvement of the termination structure and the replacement of the bearing of liquid nitrogen pump. Following the proper process, the reliability assessment test including He leakage detection and the stability of flow rate was performed. This paper describes the process and result of the first regular maintenance of KEPCO HTS cable system

• ETRI Journal
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• v.36 no.3
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• pp.407-417
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• 2014

A new-generation video coding standard, named High Efficiency Video Coding (HEVC), has recently been developed by JCT-VC. This new standard provides a significant improvement in picture quality, especially for high-resolution videos. However, one the most important challenges in HEVC is time complexity. A quadtree-based structure is created for the encoding and decoding processes and the rate-distortion (RD) cost is calculated for all possible dimensions of coding units in the quadtree. This provides a high encoding quality, but also causes computational complexity. We focus on a reduction scheme of the computational complexity and propose a new approach that can terminate the quadtree-based structure early, based on the RD costs of the parent and current levels. Our proposed algorithm is compared with HEVC Test Model version 10.0 software and a previously proposed algorithm. Experimental results show that our algorithm provides a significant time reduction for encoding, with only a small loss in video quality.

• Journal of Korea Multimedia Society
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• v.6 no.1
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• pp.105-113
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• 2003

In CDMA cellular system, inefficient Channel assignment for high-speed mobile host increase call blocking probability For it has been method proposed to guarantee QoS upon tn the speed of hierarchical cell that is allocated Queues and dedicated channels of high speed mobile host's speed. In this paper, We allocated the dedicated channel of high-speed handoff In FA (Foreign Agent), only if the receive signal strength of mobile host in current cell that there is low traffic in HA (Home Agent). also, we created new Circular queue LiFA (Limited Foreign Agent) for high-speed handoff call that signal strength is weak in certain FA, and had this High-speed handoff call to be ready for Life time to the new Circular queue LiFA. Thus improve the rate of the forced call termination.

• Journal of Chest Surgery
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• v.27 no.7
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• pp.563-570
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• 1994

Effect of ischemic preconditioning on left ventricular function after cardiac arrest in isolated rat heart.Ischemic preconditioning reduces infarct size caused by sustained ischemia. However, the effects of preconditioning on post ischemic cardiac function are not well-known. The objective of the present study was to determine whether preconditioning would improve the recovery of left ventricular functions after cardiac arrest in isolated rat heart model.Isolated rat hearts were allowed to equilibrate for 20 minutes and were then subjected to either 5 minutes of global, normothermic transient ischemia [Group 2 and 4] or not [Group 3]. A stabilization period of perfusion lasting 5 minutes after the termination of transient ischemia was followed by a standard global, normothermic 20 minute-ischemia and 35-minute reperfusion challenge [Group 3 and 4]. These following results were odtained.1. The recovery of left ventricular developed pressures showed no significant differences between Group 3 and Group 4 at 50 [P>0.3] and 85 minute [P>0.2].2. Heart rates showed no significant differences throughout all the course of experiment and between groups [P>0.5].3. The recovery of left ventricular maximum dP/dt showed no significant differences between Group 3 and Group 4 at 50 [P>0.1] and 85 minute [P>0.2].4. The recovery of pressure-rate products showed no significant differences between Group3 and Group 4 at 50 [P>0.5] and 85 minute [P>0.1].These results suggest that ischemic preconditioning does not provide significant benefit for the postischemic left ventricular functions in isolated rat hearts.