• Journal of Oral Medicine and Pain
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• v.30 no.4
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• pp.447-455
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• 2005

The purpose of this study was to examine the effect of Nd:YAG laser irradiation for sensory nerve conduction change. Nd:YAG laser was irradiated to mental region for 5 minutes with the parameters that 10 Hz and 20 Hz of 100 mJ/pulse. Target size of irradiation was 30 mm diameter of circle and target-tip distance was about 10 mm. Therefore, the power density were 212 $mW/cm^2$ and 424 $mW/cm^2$. Sensory nerve conduction was evaluated with $Neurometer^{\circled}$ CPT/C before and after Nd:YAG laser irradiation. As an outcomes, the current perception threshold(CPT) and pain tolerance threshold(PTT) were obtained. We made a comparison of these two values and the results were as follows. 1. There was no significant difference in CPT at 1W, 10 Hz and 2 W, 20 Hz Nd:YAG laser irradiation. 2. There was no significant difference in PTT at 10 Hz, 20 Hz of 100 mJ/pulse Nd:YAG laser. 3. There were no significant differences in CPT and PTT between 1 W, 10 Hz group and 2 W, 20 Hz group. Therefore, We can make a conclusion that Nd:YAG laser irradiation to mental region have no effect on mental nerve conduction in our study model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.177-182
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• 2011

This study was designed to evaluate the effect of Yukwa prepared by addition of green tea powder on change of lipid composition and body weight in mouse model. Mice were fed with Yukwa containing the five different types of green tea powders such as Bucho-cha, Okro-cha, Yongjeong-cha, Oolong-cha and Hong-cha with a normal diet. Body weight changes of Yukwa fed mice were measured once in a week for seven weeks. After seven weeks, mice were sacrificed and serum and tissues were collected for the following: adipose tissue weight, liver morphology, adipose tissue size and cholesterol content. The Yukwa combination with green tea fed mice reduced all the parameters compared to Yukwa alone fed mice. In conclusion combination with green tea showed reducing effect of hypocholesterolemia, which suggests the possibility of application to green tea as a food ingredient.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.179-186
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• 2007

This paper has investigated a rise of water level in upstream and downstream of bridge, which is caused by accumulation of debris in a bridge. The debris has been classified into several types in terms of size. The rise of water level which has been caused by installation and removal of sheet pile that is used to block water in a bridge has been analyzed using HEC-RAS model. According to the analysis, it has turned out that the debris has no influence on the rise of water level in ordinary water flow. In addition, sheet pile has little impact on the rise of water as well. Even though the impact of sheet file has turned out trivial in flood flow just like the ordinary water flow, it's been simulated that the maximum water level difference between upstream and downstream of bridge turned out more than 1.0meter because of debris in 80-year or more flood frequency. When the rise of water level in upstream from the cross section of the bridge was investigated based on 100-year flood frequency, besides, it has turned out that it had an influence up to 17.84km distance because of the effect of debris.

• Journal of Korean Academy of Nursing
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• v.30 no.1
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• pp.183-193
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• 2000

This main purpose of this study was to assess the effects of two different types of ethics education on the moral judgement of clinical nurses. One type was free discussions among nurses with given specific moral issues and the other type was discussions guided by experts on specific moral issues. The study employed a quasi-experimental, nonequivalent pre test-post test design using two different control groups. The conceptual framework of the study was derived from the Kohlberg′s Moral Development Theory (1969) and the Greipp′s Ethical Decision-Making Model (1992). The data was collected during the period of October 14 through December 15, 1998. Sample consists of 32 nurses working in the ICU who met research criteria. 16 nurses were assigned to the free discussion group and 16 nurses to the group for the guided discussion with experts group. For the pre-test, the DIT which was developed by Rest (1984) and JAND by Ketefian (1998) were used with some modification by the author. After the education, only JAND was used to assess the changes in moral judgement. The collected data was analysed using SPSS PC program. The findings are as follows: 1. There was no significant difference between two groups in their general characteristics. Only difference which was statistically significant between two groups was that realistic score on Case 3/Medical Research and Autopsy was higher in the free discussion group. 2. Hypothesis 1: "There will be a difference on the moral judgement of nurses before and after they receive an ethics education". This hypothesis was supported partially. Those who had low scores on moral judgement before the education tended to have higher scores after the education on the same issues. And, after the education, the nurses tend to give lower scores on the dilemmas they had experienced frequently at work; while giving higher scores on those dilemmas they had no prior experience. 3. Hypothesis 2: "The effect of education may differ depended upon the moral development index [P(%)] score of nurses". The effect of education was different depend on moral development level. The group who′s P(%) scores was low at the pretest has higher scores in realistic moral judgement after the education, while the groups with middle or high P(%) scores went down after the education. These changes were statistically significant in some cases, thus, the Hypothesis 2 was partially supported 4. Hypothesis 3: "The method of ethics education will have different effects on the moral judgement of nurses". Even though several nurses attended the guided discussion stated that the education program broadend their perspectives the difference between two groups was not significant and this hypothesis was not supported. In conclusion, both types of ethics education had helped the nurses to acquire the skills to deal some nursing dilemmas. The effects of ethics education may differ according to the moral development index - P(%) score. However, because of some of the limitations of this study, mainly small sample size, short term education, unable to control other variables which may affect moral judgement of nurses, further research is warranted.er research is warranted.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.4
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• pp.401-413
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• 2013

Slurry shield tunnelling ensures stability by pressurizing the tunnel face with the slurry contained in the chamber. It resists water and earth pressure in order to prevent the failure in the tunnel face during tunnel excavation. If the ground is relatively coarse, slurry can not clog the tunnel face and excessive slurry infiltration will occur. In this case chemical compounds or additives should be added to the slurry in order to improve the clogging phenomena at the tunnel face. In this study, the effect of the carbon dioxide gas as an additive to the slurry instead of chemical compounds on the capability of enhancing the clogging in the tunnel face is investigated. Bubbles arising from the carbonate-added slurry are trapped in the soil voids enhancing the clogging capability. This effect is studied in this paper by performing laboratory model tests simulating in-situ conditions, and by adopting the fine particle clogging theory. Tunnel face stability analysis was also performed and it was found that the effective size ($D_{10}$) of soils which can guarantee tunnel stability utilizing the carbonate-added slurry increased from 1.0 mm up to 2.6 mm. Moreover, Stability analysis showed that the tunnel face is stable if the ${\lambda}$(deposition coefficient) value is greater than $0.007sec^{-1}$.

• KDI Journal of Economic Policy
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• v.35 no.2
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• pp.71-105
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• 2013

Now that fiscal soundness is increasingly important influenced by the euro area fiscal crisis, early budget execution has been under the spotlight as a tool for economy control, other than typical expansionary method, such as supplementary budget. Basically, early budget execution is a fiscal policy instrument that reponses to economic fluctuations through modifying the inter-temporal allocation of fiscal expenditure within budget, without affecting fiscal soundness. This study empirically examines how effective the intert-temporal reallocation of fiscal expenditure is in economy control. Using Korea's Consolidated Fiscal data, the size of inter-temporal reallocation of fiscal expenditure is defined as changes of fiscal expenditure for one year excluding seasonal factors and used to explain real economic growth rate, a dependent variable. The result shows that the macroeconomic effect of the inter-temporal reallocation turns out meaningful in general, though some policy time lag exists. Meanwhile, a simulation using macroeconomic model finds that overall effect on economic growth is not large because increase in fiscal expenditure allocation at a certain point of time is canceled by the opposite direction within the same fiscal year. However, the inter-temporal reallocation is found to reduce volatility of key macroeconomic variables so as to contribute to partially stabilizing macroeconomy. In particular, such effect of economic stabilization seems to be highly apparent at the time of financial crisis, but not very noticeable in normal economic cycle.

• Journal of Korea Technology Innovation Society
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• v.11 no.2
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• pp.145-170
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• 2008

The existence of network is indeed the single most important factor that brings about new business phenomena in the new digital economy, especially in the IT industry. Network effect refers to a phenomenon that the increase in size of the network leads to increased network value and user utility. It determines the competitive structure of an industry and the performances of industry competitors (Shapiro and Varian, 1999). The phenomenon of increasing returns and winner-take-all enjoyed by the early winner in the competition can be attributed to the existence of positive feedback which increases the value of network and induces more users into join the network (Arthur, 1996; Shapiro and Varian, 1999; Song and Lee, 2003). This research attempts to shed light on the topic of innovation and competitive strategy of network-based industries. We analyze the case of the Korean mobile communications industry, in which a shift in technological paradigm from 2G to 3G brought new changes to the competitive structure of the industry. The Korean mobile communications industry makes an ideal case for analysis since it is an industry whose value is inherently dependent upon its user network. It is characterized by the typical increasing returns, in which a monopolizing player is enjoying firstmover's network effects. Because of the existence of network in the mobile communications industry, latecomers' disruptive innovations could not outcompete the incumbent's sustaining innovations. The contribution of this research lies in laying a groundwork for future studies by introducing a numerical simulation model to analyze the complexity theory and network effect.

• Journal of Nutrition and Health
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• v.50 no.5
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• pp.437-446
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• 2017

Purpose: This meta-analysis aimed to evaluate the effect of cassia cinnamon (Cinnamomum. cassia and C. aromaticum) on the glycemic response with a focus on the preparation of dehydrated powder and water extract. Methods: We searched Pubmed, Cochrane, EMBASE, Science Direct, and the Korean Studies Information Service System (KISS) through May 2017. In the meta-analysis for the preparation of powder, eight trials reporting fasting blood glucose (FBG), four trials reporting HbA1c, and three trials reporting the postprandial glycemic response were included. For the water extract, six trials reporting FBG and four trials reporting HbA1c were eligible for this study. A random-effects model was used to calculate the pooled effect size. Results: Cassia cinnamon powder intake significantly lowered FBG by -1.55 mmol/L (95% CI, -2.45, -0.64; p = 0.001) and the AUC of postprandial blood glucose level by $-51.8mmol/L{\cdot}min$ (95% CI, -85.5, -18.1; p = 0.003). There was a significant difference in FBG between water extract of cinnamon and placebo of -0.76 mmol/L (95% CI, -1.09, -0.43; p = 0.000). However, blood HbA1c level was not significantly altered by any preparation of cinnamon. No statistical heterogeneity was observed for any analysis except in the case of FBG for cinnamon powder. Results of funnel plots and Egger's regression suggest a low likelihood of publication bias in all biomarkers (p > 0.05). Conclusion: According to this meta-analysis, there was possible evidence to support a relationship between cassia cinnamon intake and fasting glucose in both preparation of powder and water extract. Furthermore, new evidence of the health benefits on postprandial glucose regulation of cinnamon powder was obtained.

• Journal of Korea Port Economic Association
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• v.35 no.1
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• pp.57-76
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• 2019

This study deals with the determinants of employment productivity of transportation labor, who are the main agents of the transportation industry that has made significant contributions to our country's industrial development. The study selected the determinants of employment productivity using the Korea Labor and Income Panel Study data, and analyzed the effects of various factors using panel logistic regression, panel OLS model, and panel robust regression. The results were as follows. First, a more positive effect was shown when employees held a regular job, had a "high level of education", "joining the labor union" and "experiencing vocational training". Second, in the case of job security, having a "high level of education" and "joining the labor union" showed a more positive effect; further, job security was higher for employees who worked in a "big company" or were "married". Third, in the case of higher income productivity, higher values of "age", "academic ability" and "company size" had a more positive effect, whereas larger values of "education" and "health condition except job training" had a negative one. Fourth, in the case of job satisfaction, "female", "joining the labor union" and having a higher "income" or "job security" led to higher satisfaction and a better "health condition compared to an average person". Further, a higher "overall life satisfaction" and "economic level" led to lower job satisfaction. The analysis of the determinants of employment productivity of transportation business and seeking for improvement plan is expected to improve the employment productivity in the transportation business.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.520-530
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• 2021

Objectives: This study aimed to identify the effects of music therapy on cognitive function, agitation, anxiety and depression in the elderly with dementia. Method: A comprehensive literature search was performed on PubMed, EMBASE, Cochrane Library, CINAHL, Web of Science, Google scholar and PsycINFO, for the period 2010 to 2019. In the meta-analysis, the standardized mean difference (Hedges' g) and 95% confidence interval were calculated as summary measure, and the random effect model and inverse variance method were applied using the RevMan 5.4 program. A total of 13 studies were included; all were determined to be acceptable, based on the Cochrane collaboration's tool for assessing risk of bias. Results: The effect size (Hedges' g) was 0.31 (95% CI: -0.02, 0.65) for cognition and -0.03 (95% CI: -0.17, 0.11) for agitation behavior as the primary outcomes, and 0.61 (95% CI: -1.17, -0.05) for anxiety and -0.44(95% CI: -0.88, 0.00) for depression as the secondary outcomes. Subgroup analysis by type of music intervention revealed that combined music therapy has a significantly increasing beneficial effect on cognition of dementia patients (g=0.45[95% CI: 0.03, 0.87]). Conclusion: Music therapy was determined to exert beneficial effects in reducing anxiety and depression, and combined music therapy demonstrated improved cognitive functions in elderly patients with dementia.