• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.43-50
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• 1999

The safety-evaluation of ancient wood structures has been executed with only visual inspection. The application of NDE(nondestructive evaluation) is required because the visual inspection has many restrictions. Among many NDE techniques, the stress wave technique was used in this research. This study focused on evaluating the extent of decay in members of ancient structures, using stress wave nondestructive technique. For application of stress wave technique to ancient structures, the threshold time which divides members into categories according to degree of decay should be determined in advance. Stress wave timer (Metriguard Model 239A) was used in this study, specimens used in this research were the members obtained from six ancient structures. All specimens were identified as Hard Pine(Pinus densiflora S. et Z. or Pinus thunbergii P.) by microscope. Each member was tested with stress wave passing radially through the pith. In this study, the stress wave time of $12{\mu}s$/cm could distinguish between sound and decayed specimens with accuracy of 77.5 percent. Also, decayed specimens could be separated into moderate and severe categories by stress wave time of $20{\mu}s$/cm. Among the three decay location groups (exterior, mixed, interior), the exterior group could be classified into sound, moderate and severe decay with the greatest accuracy. Stress wave transit time was not sensitive to small decay pockets located in interior of the member.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.305-311
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• 1996

This study was to seek menu model in usual dishes to guarantee the optimum salt intake considering the optimum gustation of salt surveyed on Korean adults. First, a pilot test was practiced using rice gruel to determine the criteria and a meaningful interval of salt concentration. Based on the criteria and interval so determined, a test was performed to seek the optimum gustation of salt concentration in usual diets. Subjectgroup for the above tests was university students living in Kyung-Book area. The results were as follows: 1. Mode value of the optimum gustation of salt was 0.5% and the received threshold difference of salt was 0.2% in the pilot test. 2. Mode values of the optimum gustation of salt in a la carte, soups and stews were lower than those of other side dishes. 3. But the portion size of a la carte, soups and stews is much larger than that of other side dishes, so that a la carte, soups and stews are sources of relatively larger amount of salt than other side dishes. 4. Considering the recommended optimum salt intake, it is desirable to reduce the amount of stock in soups and stews and to select fried food or salad more frequently.

• KDI Journal of Economic Policy
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• v.33 no.2
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• pp.145-175
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• 2011

We analyse an overlapping generation model in which economic agents, especially their income distribution, influence environmental policy and redistributive policy through political decision making process. In an economic equilibrium which doesn't consider political process, the introduction of environmental policy is shown to increase economic growth rate. In contrast to an economic equilibrium, environmental policy can be adopted when economic inequality reduces to a certain threshold in a political economic equilibrium. The adoption of environmental policy, on the other hand, incurs the demand of strengthened redistributive policy, which in turn decreases economic growth in a short run. We discuss broad policy implications based on our political economic analyses.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.832-841
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• 2016

The voltage-frequency island (VFI) design paradigm has strong potential for achieving high energy efficiency in communication centric manycore system-on-chip (SoC) design called network-on-chip (NoC). However, because of the diminished scaling of wire-dimension and supply voltage as well as threshold voltage in modern CMOS technology, the vulnerability to link failure in VFI NoC is becoming a crucial challenge. In this paper, we propose an energy-optimized topology generation technique for VFI NoC to cope with permanent link failures. Based on the energy consumption model, we exploit the on-chip communication traffic patterns and characteristics of link failures in the early design stage to accommodate diverse applications and architectures. Experimental results using a number of multimedia application benchmarks show the effectiveness of the proposed three-step custom topology generation method in terms of energy consumption and latency without any degradation in the fault coverage metric.

• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.81-87
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• 1991

We propose the crack growth rate equation which will model fatigue crack growth rate behavior such that constant stress amplitude fatigue crack growth behavior can be predicted. Constant stress amplitude fatigue tests are conducted for four materials under three stress ratios of R＝0.2, R＝0.4 and R＝0.6. Materials which have different mechanical properties i.e. stainless steel, low carbon steel, medium carbon steel and aluminum alloy are used. Through constant stress amplitude fatigue test by using unloading elastic compliance method, it is confirmed that crack closure is a close relationship with fatigue crack propagation. We describe simply fatigue crack propagation behavior as a function of the effective stress intensity factor range ($\Delta$ $K_{eff}$＝U .$\Delta$K) for all three regions (threshold region, stable region). The fatigue crack growth rate equation is given by da / dN＝A($\Delta$ $K_{eff}$­$\Delta$ $K_{o}$ )$^{m}$ / ($\Delta$ $K_{eff}$­$\Delta$K) Where, A and m are material constants, and $\Delta$ $K_{o}$ is stress intensity factor range at low $\Delta$K region. $K_{cf}$ is critical fatigue stress intensity factor.actor.

• Journal of Korean Academy of Nursing
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• v.34 no.5
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• pp.722-728
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• 2004

Purpose: This study was designed to determine the predictors of postpartum depression. Method: One hundred-sixty one women within one year after delivery from one public health center located in the northern area of Seoul were used in this study. The instruments were a survey of general characteristics, the Edinburgh Postnatal Depression Scale, recent life events index, perceived social support from family, Quality of marriage index, parenting stress index, and Rosenberg's self-esteem inventory. Data was analysed using descriptive statistics, Pearson correlation coefficients, and logistic regression. Result: The average item score of the EPDS was 6.67. 12.4% of respondents, who scored above a threshold 12, were likely to be suffering from a depression of varying severity. The fitness of the model for explaining postpartum depression from six variables, plan for pregnancy, family support, quality of marital relation, perceived social support, life events, childcare stress, and self-esteem, was statistically significant and the predictive power of these variables was 90.9%. The significant predictors of postpartum depression were family support and child care stress. Conclusion: Further research is needed to identify the prevalence rate of postpartum depression using more reliable sampling methods from a large general population. Nursing interventions need to be developed for promoting family support and reducing childcare stress.

• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.284-288
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• 2010

Video surveillance is widely used in establishing the societal security network. In this paper, intrusion detection based on visual information acquired by static camera is proposed. Proposed approach uses background model constructed by approximated median filter(AMF) to find a foreground candidate, and detected object is calculated by analyzing motion information. Motion detection is determined by the relative size of 2D object in RGB space, finally, the threshold value for detecting object is determined by heuristic method. Experimental results showed that the performance of intrusion detection is better one when the spatio-temporal candidate informations change abruptly.

• BMB Reports
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• v.39 no.6
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• pp.766-773
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• 2006

Fragile-X-syndrome (FXS) is the most common type of inherited cognitive impairment. The underlying molecular alteration consists of a CGG-repeat amplification within the FMR-1 gene. The phenotype is only apparent once a threshold in the number of repeats has been exceeded (full mutation). The aim of this study was to characterize the FMR-1 CGG-repeat status in Argentine patients exhibiting mental retardation. A total of 330 blood samples from patients were analyzed by PCR and Southern blot analysis. Initially, DNA from 78 affected individuals were studied by PCR. Since this method is unable to detect high molecular weight alleles, however, we undertook a second approach using the Southern blotting technique to analyze the CGG repeat number and methylation status. Southern blot analysis showed an altered pattern in 14 out of 240 (6%) unrelated patients, with half of them presenting a mosaic pattern. Eight out of 17 families (47%) showed a (suggest deleting highlight). The characteristic FXS pattern was identified in 8/17 families (47%), and in 4 of these families 25% of the individuals presented with a mosaic model. The expansion from pre-mutation to full mutation was shown to occur both at the pre and post zygotic levels. The detection of FXS mutations has allowed us to offer more informed genetic counseling, prenatal diagnosis and reliable patient follow-up.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06d
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• pp.360-365
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• 2010

In this paper, we present a distributed algorithm for detecting dynamic event regions in wireless sensor network with the consideration on energy saving. Our model is that the sensing field is monitored by a large number of randomly distributed sensors with low-power battery and limited functionality, and that the event region is dynamic with motion or changing the shape. At any time that the event happens, we need some sensors awake to detect it and to wake up its k-hop neighbors to detect further events. Scheduling for the network to save the total power-cost or to maximize the monitoring time has been studied extensively. Our scheme is that some predetermined sensors, called critical sensors are awake all the time and when the event is detected by a critical sensor the sensor broadcasts to the neighbors to check their sensing area. Then the neighbors check their area and decide whether they wake up or remain in sleeping mode with certain criteria. Our algorithm uses only 2 bit of information in communication between sensors, thus the total communication cost is low, and the speed of detecting all event region is high. We adapt two kinds of measure for the wake-up decision. With suitable threshold values, our algorithm can be applied for many applications and for the trade-off between energy saving and the efficiency of event detection.

• Smart Media Journal
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• v.9 no.3
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• pp.80-89
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• 2020

Out - of - distribution (OOD) samples are frequently encountered when deploying a classification model in plenty of real-world machine learning-based applications. Those samples are normally sampling far away from the training distribution, but many classifiers still assign them high reliability to belong to one of the training categories. In this study, we address the problem of removing OOD examples by estimating marginal density estimation using variational autoencoder (VAE). We also investigate other proper methods, such as temperature scaling, Gaussian discrimination analysis, and label smoothing. We use Chonnam National University (CNU) weeds dataset as the in - distribution dataset and CIFAR-10, CalTeach as the OOD datasets. Quantitative results show that the proposed framework can reject the OOD test samples with a suitable threshold.