• Structural Engineering and Mechanics
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• v.70 no.1
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• pp.81-96
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• 2019

In this paper, a hybrid uncertain model is applied to system reliability based design optimization (RBDO) of trusses. All random variables are described by random distributions but some key distribution parameters of them which lack information are defined by variation intervals. For system RBDO of trusses, the first order reliability method, as well as monotonicity analysis and the branch and bound method, are utilized to determine the system failure probability; and Improved (${\mu}+{\lambda}$) constrained differential evolution (ICDE) is employed for the optimization process. System reliability assessment of several numerical examples and system RBDO of different truss structures are proposed to verify our results. Moreover, the effect of different classes of interval distribution parameters on the optimum weight of the structure and the reliability index are also investigated. The results indicate that the weight of the structure is increased by increasing the uncertainty level. Moreover, it is shown that for a certain random variable, the optimum weight is more increased by the translation interval parameters than the rotation ones.

• KDI Journal of Economic Policy
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• v.43 no.2
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• pp.81-101
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• 2021

This paper estimates the expectation-augmented Phillips curve, which explains inflation dynamics, in Korea. The phenomenon of low inflation in Korea has been going on for quite some time, in particular since 2012. During the Covid-19 crisis, due to low inflation expectations the operation of monetary policy was limited as the base rate approached the zero lower bound. The main objective of this paper is to estimate where and how tightly inflation expectations are anchored. It was found that long-term inflation expectations fell to around 1%, falling short of the inflation target, and that inflation expectations are strongly anchored to long-term expectations, which implies that the low inflation phenomenon is likely to extend into the future. The results also imply that even if inflation fluctuates due to temporary disturbances, it may converge to a level below the inflation target. The slight rebound of long-term expectations during the Covid-19 crisis suggests that the aggressive monetary policy may have contributed to improving economic agents' beliefs about the commitment of monetary authorities to inflation stability. This may also help long-term expectations gradually to approach the inflation target.

• Journal of Wellness
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• v.7 no.2
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• pp.101-111
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• 2012

The benefits and risks of whole body vibration (WBV) based acceleration training on the human body have been documented for many years. WBV training has been shown to increase muscular strength, explosive power, bone strength, performance, mobility, cardiovascular function, circulation and anabolic hormone level and so on. The purpose of this review is correct understanding and application of WBV training. Without proper understanding, rather, to apply WBV to the human body can be fatal harm, and therefore know that what is vibration and has advantages and disadvantages. If there is anything positive side there is bound to the negative aspects. In this regard, WBV training can have a positive impact on the already confirmed by several studies and also, there have been scientifically proven. But still we are part of a scientific approach that is acceptable even to keep in mind that you will always coexist. Once again, the effect of WBV with a physical stimulus that risk and should be remembered. In addition, given the momentum and how to exercise and well-being well aware that vibration exercise as a way to think of how not to be familiar with.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.2
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• pp.209-214
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• 2020

The equitable partitioning problem(EPP) is classified as [0/1] binary skill existence or nonexistence and integer skill levels such as [1,2,3,4,5]. There is well-known a polynomial-time optimal solution finding algorithm for binary skill EPP. On the other hand, tabu search a kind of metaheuristic has apply to integer skill level EPP is due to unknown polynomial-time algorithm for it and this problem is NP-hard. This paper suggests heuristic greedy algorithm with polynomial-time to find the optimal solution for integer skill level EPP. This algorithm descending sorts of skill level frequency for each field and decides the lower bound(LB) that more than the number of group, packing for each group bins first, than the students with less than LB allocates to each bin additionally. As a result of experimental data, this algorithm shows performance improvement than the result of tabu search.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.67-73
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• 1999

The insulin-like growth factor (IGF)s are believed to one of several growth factors that play an adjunctive role in ovarian follicular development. These factors circulate bound to a family of IGF-binding protein (IGFBP)s. It is known that circulating IGFBPs are involved in the transport of IGFs to tissues and modulate IGFs actions at local tissue. The purposes of this study were to evaluate changes in serum IGFBPs profiles during normal ovulatory menstrual cylce and to compare serum IGFBPs profiles in periovulatory phase of between normal ovulatory menstrual cylce and controlled hyperstimulated cycle. Fasting blood samples were obtained from 15 normal healthy women throughout normal ovulatory menstural cyle and on the day of aspiration of oocyte from 10 patients undergoing ovarian hyperstimuation for in vito fertilization-embryo transfer. Serum IGFBP-1 - IGFBP-4 were measured by western ligand blot and immunoprecipitation. Serum $17{\beta}$-estradiol was determined by radioimmunoassay. Type and molecular weight of serum IGFBP did not changed during normal ovulatory menstural cycle. No significant variation in the relative proportion and level of each IGFBP was found throughout normal ovulatory menstural cyle. Also, the relative proportion and level of each IGFBP did not correlated with serum $17{\beta}$-estradiol level. There was no significant difference in the relative proportion and level of each serum IGFBP between on the day of ovulation in normal ovulatory menstrual cylce and on the day of aspiration of oocyte in controlled hyperstimulated cycle. Our data indicate that IGFBPs have regulatory functions in ovary through an paracrine and autocrine rather than endocrine mechanism during normal ovulatory menstural cycle.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.52-57
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• 2005

Previous studies showed that shell meal fertilizer from the oyster farming industry could be a potential inorganic soil amendment to increase Chinese cabbage productivity and to restore the soil nutrient balance in upland soil (Lee et al., 2004). Herein, shell meal fertilizer was applied at rates of 0, 4, 8, 12, and $16Mg\;ha^{-1}$ to upland soil (Pyeontaeg series, Fine silty, Typic Endoaquepts) for Chinese cabbage cultivation. We found available phosphate increased significantly with shell meal fertilizer application, due to high content of phosphate ($1.5g\;P_2O_5\;kg^{-1}$) in the applied shell meal fertilizer. In addition, high pH of shell meal fertilizer contributed to increase available phosphate content by neutralization of acidic soil. Total and residual P contents increased significantly with increasing shell meal fertilizer application, but we could not find any tendency in organic and inorganic P fraction. Of extractable P fraction, water-soluble phosphorus (W-P) and calcium-bound P (Ca-P) contents increased significantly with increasing application level. By contrast, aluminum and iron-bound P (Al-P and Fe-P) decreased slightly with shell meal application. The present experiment indicated that shell meal fertilizer had a positive benefit on increasing available phosphate content in arable soil. And so the increased available phosphate by shell meal fertilizer may decrease phosphate application level and then reduce phosphorus loss in arable soil.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.373-379
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• 2001

The objectives of this study were to assess implementation on tariff quotas and tariff cuts committed in the WTO as result of Uruguay Round(UR) negotiations and to examine impacts of reductions in agricultural protection agreed in the UR on major non-timber forest products markets. The implementation of WTO Agreement on Agriculture was analysed based on the relevant data and statistics. The impacts of implementation on tariff cuts and tariff quotas on non-timber forest products markets were estimated by using supply and demand elasticities from previous studies and data on production, consumption and trade after UR. The quantities of Chestnut, Pine nut and Jujube imported by the system of tariff quota did not exceed the committed quotas over the five years from 1995 to 1999. The current level of applied rates on imports of non-timber products is much lower than that of bound rates, which will be maintained until the year 2004. It is estimated that increase in imports after UR reduced prices and that reduction in prices led to decrease in expenditure and to increase in consumer surplus. It is estimated, however, that production level significantly decreased due to rise in imports and that the negative effects on production exceeded positive effects on consumption. Exports of most non-timber forest products decreased after UR even though non-timber forest products could gain access to the export markets at the lower tariffs as a result of UR.

• Corrosion Science and Technology
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• v.8 no.2
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• pp.74-80
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• 2009

The high alkaline property in the concrete pore solution protects the embedded steel in concrete from corrosion due to aggressive ions attack. However, a continuous supply of those ions, in particular, chlorides altogether with a pH fall in electrochemical reaction on the steel surface eventually depassivate the steel to corrode. To mitigate chloride-induced corrosion in concrete structures, finely grained mineral admixtures, for example, pulverized fuel ash (PFA), ground granulated blast furnace slag (GGBS) and silica fume (SF) have been often advised to replace ordinary Portland cement (OPC) partially as binder. A consistent assessment of those partial replacements has been rarely performed with respect to the resistance of each binder to corrosion, although the studies for each binder were extensively looked into in a way of measuring the corrosion rate, influence of microstructure or chemistry of chlorides ions with cement hydrations. The paper studies the behavior of steel corrosion, chloride transport, pore structure and buffering capacity of those cementitious binders. The corrosion rate of steel in mortars of OPC, 30% PFA, 60% GGBS and 10% SF respectively, with chloride in cast ranging from 0.0 to 3.0% by weight of binder was measured at 7, 28 and 150 days to determine the chloride threshold level and the rate of corrosion propagation, using the anodic polarization technique. Mercury intrusion porosimetry was also applied to cement pastes of each binder at 7 and 28 days to ensure the development of pore structure. Finally, the release rate of bound chlorides (i.e. buffering capacity) was measured at 150 days. The chloride threshold level was determined assuming that the corrosion rate is beyond 1-2 mA/$m^3$ at corrosion and the order of the level was OPC > 10% SF > 60% GGBS > 30% PFA. Mercury intrusion porosimetry showed that 10% SF paste produced the most dense pore structure, followed by 60% GGBS, 30% PFA and OPC pastes, respectively. It was found that OPC itself is beneficial in resisting to corrosion initiation, but use of pozzolanic materials as binders shows more resistance to chloride transport into concrete, thus delay the onset of corrosion.

• Journal of Korean Society of Transportation
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• v.23 no.6 s.84
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• pp.31-40
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• 2005

Main airports in the Intra-Asian market have faced competition not only to attract China-bound transshipment cargoes but also to be hub airport in same region. In spite of such a importance, the previous research has been short of evaluation of airport competitiveness. Implication of the previous research has mainly been focused on evaluation of airport critical factor service qualify and efficiency. The aim of this paper is to present critical points that affect airport competitiveness using an algorithm based on reversed fuzzy evaluation and senario method. The results of senario analysis and reversed fuzzy evaluation shows that Incheon international airport needs to enhance service level of 7% as a result of senario analysis and service level of 5% and brand equity level of 10% at the same time as a result of reversed fuzzy evaluation analysis, to ensure competitiveness in same region.

• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.65-67
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• 2004

O-GlcNAcylation of p53 has been already identified and reported, but the function of O-GlcNAc on p53 has not been studied well. In this report, the general function of O-GlcNAc modification on p53 has been investigated using mouse fibroblast cell, L929. When streptozotocin (STZ), a non-competitive O-GlcNAcase inhibitor was treated to L929, O-GlcNAc modification level was dramatically increased on nucleocytoplasmic proteins, including p53. Because it has been already reported that $TNF\alpha$ induced the production of p53 in L929, $TNF\alpha$ was treated to obtain more p53. Approximately two times more amount of p53 was found from the cells treated STZ and $TNF\alpha$ simultaneously compared to the cell treated $TNF\alpha$ alone. The p53 increment in the presence of STZ was not caused by the induction of p53 gene expression. When new production of p53 induced by the $TNF\alpha$ was inhibited by the treatment of cycloheximide, O-GlcNAc modification decreased and phosphorylation increased on pre-existing p53 after $TNF\alpha$ treatment. But in the presence of STZ and $TNF\alpha$ at the same time, more O-GlcNAcylation occurred on p53, The level of ubiquitination on p53 was also reduced in the presence of STZ. Approximately three times less amount of Mdm2 bound to this hyperglycosylated p53. From this result it might be concluded that treatment of STZ to inhibit O-GlcNAcase increased O-GlcNAc modification level on p53 and the increment of O-GlcNAc modification stabilized p53 from ubiquitin proteolysis system.