• International Journal of Highway Engineering
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• v.18 no.5
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• pp.49-56
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• 2016

PURPOSES : In this study, noise reduction effect of a two-layer porous asphalt pavement was investigated through site measurement and computer simulation. METHODS : To examine noise reduction effect, a 3 km long quiet pavement was installed by removing previous normal pavement, which had a rather low porosity. The studied site was a high-rise apartment building surrounded by the quiet pavement and Seoul ring road with heavy traffic volume, indicating relatively high background noise. RESULTS : The measurement result before and after installing the quiet pavement showed a noise reduction effect of 4.3 dB(A) at a distance of 7.5 m from the road. After validating the accuracy of simulation using SoundPLAN, the reduction in SPL(sound pressure level) at the facades by the quiet pavement was predicted by considering five different road conditions generating traffic noise from each road or in the combination of the quiet pavement and Seoul ring road. In the case of no noise from Seoul ring road, noise reduction at the facades was 4.2 dB(A) on average for 702 housing units. With background noise from Seoul ring road, however, the average SPL decreased to 2.0 dB(A). Regarding subjective response of noise, the number of housing units with a noise reduction of over 3 dB(A) was 229 out of 706 units (approximately 32%). For 77 housing units, the noise reduction was between 1~3 dB(A), while it was less than 1 dB(A) for 400 housing units. CONCLUSIONS : The overall result indicates that the quiet pavement is useful to reduce noise evenly at low and high floors compared to noise barriers, especially in the urban situation where background noise is low.

• Korean Journal of Social Welfare Studies
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• v.48 no.3
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• pp.5-28
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• 2017

Using 2006~2015 Korean Welfare Panel Survey data, this study analyzed the poverty reduction effects of social security benefits. The results show that social security benefits have substantial impacts on reducing the poverty gap. National Basic Livelihood Security, public pensions, and Basic Pension have relatively larger poverty reduction effects. Other benefits such as disability benefits, workers' compensation unemployment insurance, and childcare subsidies have much smaller poverty impacts. Two determining factors of the poverty reduction effect are (1)the amount and (2)the poverty reduction efficiency of social security benefits. With the expansion of the social security system in recent years, the poverty reduction efficiency has decreased in general. Due to a greater increase in the amount of benefits, however, the poverty reduction effect has gradually increased. In order to increase the anti-poverty effect of social security, it is important to find ways to improve efficiency while minimizing the disadvantages of the selectivistic welfare benefits.

• The Journal of Society for e-Business Studies
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• v.15 no.3
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• pp.163-181
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• 2010

As a part of efforts to reduce the global emissions of greenhouse gases, the Kyoto Protocol was signed by major developed countries ("Annex I" countries). According to the Kyoto protocol, the Emission Trading Scheme that derives a trading market of the $CO_2$ emission rights is appeared. It causes that business institutions give lots of efforts to reduce $CO_2$ by using new environmentally sound technologies or increasing efficiency in production. On the while there have been several studies trying to develop a methodology to measure the effect of $CO_2$ reduction and its monetary value. In this research we suggest ECRE (Evaluation of $CO_2$ Reduction in E-transformation) model which can measure the $CO_2$ reduction effect through the introduction of G2B system. ECRC model was developed based on the IPCC methodology. ECRC model measures the two major effects of the $CO_2$ reduction which are '$CO_2$ reduction effect from transportation' and '$CO_2$ reduction effect from the decrease of paper use'. In this paper, we calculate the economic effect of $CO_2$ reduction with the case of the G2B system in Korea. This research suggests a basic methodology to measure the $CO_2$ reduction performance for the e-transformed institution.

• Transactions of Materials Processing
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• v.18 no.5
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• pp.410-415
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• 2009

Experimental and numerical studies were performed to examine the effect of material temperature and reduction ratio on friction coefficient during hot flat rolling. We carried out a single pass pilot hot flat rolling test at the temperatures range of $900{\sim}1200^{\circ}C$ and measured the spread of deformed material while reduction ratio varied from 20% to 40%. Materials used in this study were a high carbon steel and two alloy steels. The dimension of specimen used in hot rolling experiment was $50mm{\times}50mm{\times}300mm$. We performed a series of finite element simulation of the hot rolling process to compute the friction coefficient change in terms of steel grade and reduction ratio. Results showed that temperature dependency of friction coefficient is not noteworthy but the effect of reduction ratio on friction coefficient is quite large. For high carbon steel, friction coefficient at reduction ratio of 30% is lower than that at that of 20%. Meanwhile friction coefficient at reduction ratio of 40% was one and half times large compared with that at that of 20%. The effect of steel grade on friction coefficient was significant when reduction ration was large, e.g., 40%.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.117-121
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• 2003

Nickel(Ni) powders were prepared from the mixture of nickel chloride and magnesium stearate by a hydrogen reduction process, and the effect of reaction temperature and the addition of magnesium stearate on the chracteristics of the powders were investigated. The effect of size reduction of nickel particles was observed in the presence of magnesium stearate owing to the inhibition of excess growth of paricles. The size reduction and the degree of agglomeration of the particles affected by the amounts of liqiud phase, which related to the increase of magnesium stearate.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.345-352
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• 2020

This study conducted a survey targeting 414 medical institution workers to identify the impacts of their emotional labor and the recognition level of medical service fee reduction influencing the reduction rate. The results were as follows. First, a review of the difference in the reduction rate by socio-demographic characteristics revealed that in both inpatient and outpatient reduction rate, there is a significant difference in the occupational description, working history at the current hospital, and the numbers of approved beds. Second, there is a correlation between emotional labor, the recognition level of medical service fee reduction, and the reduction rate. As a result of the analysis, there is a significant positive correlation between emotional labor and outpatient reduction rate, a significant negative correlation between the recognition level of medical service fee reduction and inpatient reduction rate, and a significant negative correlation between the recognition level of medical service fee reduction and outpatient reduction rate. Third, emotional labor has a significant positive effect on the inpatient reduction rate, and the recognition level of the medical service fee reduction has a negative effect on the inpatient reduction rate. The emotional labor also has a significant positive effect on outpatient reduction rate, and the recognition level of the medical service fee reduction has a significant negative effect on outpatient reduction rate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.05a
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• pp.46-48
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• 1988

The effect of cold reduction ratio on magnetic properties of 45% Ni-Fe permalloy was studied. To know the relationship between the crystal orientation and the magnetic properties, the pole figure was measured by X-ray diffraction method. In the case of single rolled reduction, the coercive force decreased with cold reduction ratio monotonically, but the maximum permeability, induction and squreness increased drastically. In the case of double rolled reduction (total reduction ratio is 90%), the saturation and residual induction increased slightly with secondary reduction ratio, but the maximum permeability and the coercive force had the maximum and the minimum value at the 50/50% reduction ratio respectively. And strong {100} <100> pole was developed by increasing the cold reduction ratio.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2292-2296
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• 2010

2020 Korea GHG reduction goal is decreasing 4% compared with that of 2005. Effective counterplan of GHG redection goal needs to set for inductrial allocation and various reduction GHG technologies and policies for transportation have been developed. Modal shifr is one of these main policy and it focused on shifting as much freight as economically meaningful under current market conditions. It improves energy efficiency, consequently reduces GHG effect. This study is proposed as a preliminary studay of analyzing Modal shift effect. modal shift of car travelers to train is concerned in Seoul-Busan section, This study is based on a scenario which can maximize passenger occupancy rate to get the GHG reduction effect and the effect of modal shift of car to train is identified. According to this result, we can get GHG reduction effect through dealing with maximizing passenger occupancy rate on train. Therefore, in order to enhance this modal shift effect, train using rate need to increased and also improvement of policies and cost system are need to be considered to promote increasing use of train.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.2
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• pp.53-64
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• 2015

Rooftop greening is the alternative of urban heat island. The purpose of this study is selecting Sedum to the effect of temperature reduction of the rooftop greening. Since the state of growth is excellent, Sedum kamtschaticum, Sedum takesimense and Sedum middendorffianum surveyed as coverage. It was investigated that there is the effect of reducing the temperature. The effect of temperature reduction of Sedum counted compound was found to be associated with state of growth. When you construct a rooftop greening, planting Sedum kamtschaticum, Sedum takesimense and Sedum middendorffianum is helpful to the effect of temperature reduction. Also, the ingredients various types of Sedum in order to reduce the effective temperature, it must be densified. It must demonstrate an additional effect of temperature reduction of Sedum through complementary and continuous monitoring of the future temperature monitoring method.

• Journal of the Korea Computer Industry Society
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• v.6 no.5
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• pp.783-790
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• 2005

In this paper, we have simulated a Symmetric Dual-gate Single-Si TFT which has three split floating n+ zones. This structure reduces the kink-effect drastically and improves the on-current. Due to the separated floating n+ zones, the transistor channel region is split into four zones with different lengths defined by a floating n+ region, This structure allows an effective reduction of the kink-effect depending on the length of two sub-channels. The on-current of the proposed dual-gate structure is 0.9mA while that of the conventional dual-gate structure is 0.5mA at a 12V drain voltage and a 7V gate voltage. This result shows a 80% enhancement in on-current. Moreover we observed the reduction of electric field in the channel region compared to conventional single-gate TFT and the reduction of the output conductance in the saturation region. In addition, we also confirmed the reduction of hole concentration in the channel region so that the kink-effect reduces effectively.