• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.25-31
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• 2020

Experimental investigations were conducted to examine the combustion characteristics of a swirl-stabilized double cone premixed burner nozzle used for industrial gas turbines for power generation. Several variants with different fuel injection patterns are tested to compare the combustion characteristics such as NOx and CO emissions, stability, and wall temperature distributions. Main results show that NOx emissions and stability are decreased either when the fuel hole diameter is decreased with the same number of fuel holes, or when the number of fuel holes is reduced with the same total area of fuel holes, both of which are due to a higher penetration of fuel into the air stream. Not only is NOx reduced but also stability is enhanced when the fuel hole diameter varies in an alternating manner with the same total area of fuel holes, showing that NOx reduction is due to a higher penetration of mean fuel injection path while stability enhancement is due to a lowered penetration of minimum fuel injection path.

• Journal of Preventive Medicine and Public Health
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• v.26 no.2 s.42
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• pp.179-191
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• 1993

Generally fatty liver is attributed either to chronic alcoholism, diabetes mellitus, or obesity. Based upon this commonly held clinical brief, this study was conducted to investigate the contributing factors of fatty liver and odds ratio (OR) of known contributing factors. A sample of 310 male participants, who visited at Seoul Paik Automated Multiphasic Health Testing System from November 1991 to December 1991, was separated into 112 cases and 198 controls by ultrasonographic fin ding. There were statistically significant difference between fatty liver and normal in triglyceride (TG), body mass index (BMI), alanine aminotransferase (ALT), high density lipoprotein cholesterol (HDL-C), fasting blood sugar (FBS), alcohol consumption, low density lipoprotein cholesterol (LDL-C), total cholesterol, gamma-glutamyl transferase ($\gamma$-GT), duration of alcohol intake and alkaline phosphatase (Alk.P)(P<0.01, P<0.05). The statistically significant elevated odds ratio were noted for TG (4.48, confidence interval (CI) 2.66-7.55, P=0.000), alcohol consumption(3.24, CI 1.56-6.23, P=0.002), BMI(3.05, CI 1.87-4.97, P=0.000), and FBS (2.59, CI 1.53-4.40, P=0,000). In summary, it is suggested that the fatty liver could be preventive by avoiding such deleterious factors as high fat diet, alcohol and obesity.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.172-177
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• 1995

The maneuverabilities of the M.S. TAMYANG are studied, based on maneuvering indices and the data obtained from her Z test. The results obtained are summarized as follows : 1. The maneuvering indices K'and T'of the M.S. TAMYANG are 0.9464, 0.6895 at 10$^{\circ}$Z test and 0.8651, 0.4224 at 20$^{\circ}$Z test and 0.8349, 0.4328 at 30$^{\circ}$Z test respectively. The above calculated values K', T'showed that her maneuverabilities are more effective when the rudder is used to small angle than to large angle. 2. As her maneuvering indices K'and T'at 10$^{\circ}$Z test are smaller than the standard maneuvering indices of fishing boats, her turning ability was found to be lower but her obeying ability higher. 3. The running distance of a turn at her 10$^{\circ}$Z test was about 8.8 times her own length and she was considered to have good maneuverabilities synthetically.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.547-547
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• 2003

The aim of this study was to compare the effects of three Ni-Ti instruments on leaning ability by evaluating the volumetric and morphological changes in the apical 6mm of the root canals before and after preparation, using three-dimensionally reconstructed root canals of extracted human teeth. Forty-five teeth were used in this study. They were opened the chambers and removed the all pulp remnants ultrasonically. Subsequently, the canal wall was coated with silver paste and prepared using ProTaper, ProFile and GT rotary files according to the manufacturers instructions. Before and after root canal preparation, all the specimens were scanned with micro computed tomography and examined the differences in dentine volume removed, canal straightening, the proportion of the unchanged area and canal transportation. Quantitative analysis revealed that instrumentation increased in canal volume ranging between 0.081 and $1.866{\;}\textrm{mm}^3$. On average, the large apical preparation produced by ProTaper demonstrated smaller proportions of unchanged surface areas compared to the two other instruments in small canals. But in large canals like maxillary central incisor, the preparation of ProTaper instruments was not enough. ProTaper instrument was tended to increase more in canal volume as compared with the other two instruments but unchanged area was no significant difference. These results showed that three instruments had similar preparation ability and micro computed tomography in combination with the coated wall of root canal using silver paste is a nondestructive and valuable tool to study root canal geometry and changes after preparations in detail.

• Journal of Nutrition and Health
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• v.45 no.5
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• pp.443-451
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• 2012

We compared the effects of grapefruit seed extract (GFSE), green tea extract (GT) and their microencapsulated extract on anti-inflammatory activities in murine RAW 264.7 macrophages cell line. In order to protect the bioactive compounds in the extracts, they were microencapsulated with maltodextrin and $H_2O$. Nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), inducible nitric oxide synthase (iNOS) protein expression and thiobarbiturate reactive substances (TBARS) were analyzed in LPS activated RAW 264.7 macrophages. The green tea extract at the range of $100-600{\mu}g/mL$ inhibited NO, PGE2 production and iNOS protein expression without cytotoxicity in a dose-dependent manner. Grapefruit seed extract had strong inhibitory effects on NO and PGE production and iNOS protein expression at the range of $5-20{\mu}g/mL$ without cytotoxicity. Microencapsulation of green tea extract had further inhibitory effects on NO and PGE2 production and on iNOS protein expression, whereas microencapsulated GFSE did not show any further inhibitory effects on these parameters. Taken together, our results suggest that GSFE might be a promising candidate for preventing inflammation related diseases, such as cardiovascular disease, cancer or diabetes, and the microencapsulation of green tea extract could improve its bioactivity.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.2
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• pp.131-139
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• 2012

In this study, the numerical analysis has been conducted in order to check behavior characteristics of liner plate made of corrugated steel from urban small sized tunnel excavation. The analysis was conducted with five kinds of conditions like 5 m, 10 m, 15 m, 20 m and 25 m to examine the behavior characteristics of liner plate according to the depth of cover. Analysis results showed that the maximum axial stress and the maximum displacement occurs in the lower end of the member, and the maximum shear stress occurs in the upper part of the member. Also, change of displacement, stress shearing stress of liner plate based on various depth of cover are existed, but the difference is slight, and by increasing depth of cover, structural stability is gradually ensured.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.351-365
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• 2002

Earlier studies have demonstrated that chromium (Cr) VI compounds have been shown to be more toxic and carcinogenic than other chromium compounds. The aim of the present work was to evaluate the antioxidant effects of red ginseng against chromium VI -induced toxicity and free radical generation. Sixty adult male rats were divided into six equal groups include: control group, group received Cr VI alone (50 mg/kg b.w.), group treated with Korean ginseng (K. ginseng) alone (20 mg/kg b.w), group treated with Cr VI for 15 days then received K. ginseng for other 15 days, group treated with Cr VI and K. ginseng at the same time for 15 days, and group treated with K. ginseng for 15 days then Cr VI for other 15 days. The results revealed that Cr VI caused significant increase in ALT, AST, ALP, G-GT, urea, creatinine, and acid phosphatase. Whereas, it caused significant decrease in TP, albumin, testosterone, GPX, and SOD indicating a stress for liver, kidney and testes. K. ginseng alone caused significant increase in GPX and SOD activities in healthy animals and this result suggests a prophylactic role for this herb in protection against the damaging impact induced by free radical species. Furthermore, the other biochemical parameters measured after K. ginseng administration were comparable to the control values. Treatment with Cr VI followed by K. ginseng, Cr VI and K. ginseng or K. ginseng followed by Cr VI resulted in significant improvement in all tested parameters towards the normal values of the controls. However, this improvement was pronounced in the group pre-treated with K. ginseng for 15 days before Cr VI administration. It could be concluded that K. ginseng exhibited a protective action against the toxic effects of Cr VI and it had the ability to scavenge free radicals resulted from Cr VI intoxication.

• Journal of Korea Trade
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• v.24 no.8
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• pp.81-100
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• 2020

Purpose - Based on complexity theory, this study develops a configurational model to predict the profitability of Halal cosmetics firms in the Indonesian and Malaysian markets. The proposed research model involves two level configurations-industry context and selling strategies-to predict high and low scores of a firm's profitability. The industry context configuration model comprises industry stability, product homogeneity, price sensitivity, and switching cost. Selling strategies include customer-focused, competitor-focused, and margin-focused approaches. Design/methodology - This is the first empirical study that calculates causal models using a combination of industry context and selling strategy factors to predict profitability. Data obtained from the marketing managers of cosmetics firms are used to test the proposed configurational model using fuzzy-set qualitative comparative analysis (fsQCA). It contributes to the current knowledge of business marketing by identifying the factors necessary to achieve profitability using analysis of condition (ANC). Findings - The results revealed that unique and distinct models explain the conditions for high and low profitability in the Indonesian and Malaysian halal cosmetic markets. While customer-focused selling strategy is necessary to attain a higher profit in both the markets, margin-focused selling strategy appears to be an essential factor only in Malaysia. Complexity of the interactions of selling strategies with industry factors and differences between across two study markets confirmed that complexity theory can support the research configurational model. The theoretical and practical implications are also illustrated. Originality/value - Despite the rapid growth of the global halal industry, there is little knowledge about the halal cosmetic market. This study contributes to the current literature of the halal market by performing a set of asymmetric analytical approaches using a complex theoretical model. It also deepens our understating of how the Korean firms can approach the Muslim consumer's needs to generate more beneficial turnover/revenue.

• Journal of Preventive Medicine and Public Health
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• v.52 no.2
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• pp.101-108
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• 2019

Objectives: To objectively determine and compare the physical activity (PA) levels of adults newly diagnosed with type 2 diabetes (T2D) and adults without T2D in Vietnam using an accelerometer. Methods: A total of 120 participants with newly diagnosed T2D and 120 adults without T2D were recruited from a large hospital in Hanoi, the capital city of Vietnam. All participants wore an ActiGraph GT3X accelerometer for at least 5 days, including 1 weekend day. Freedson cut-off points were used to estimate different intensities of PA. In addition, comparisons between groups were made with respect to achieving the World Health Organization (WHO) and International Diabetes Federation (IDF) recommended PA guidelines. Results: Men with T2D had significantly lower levels of PA than men without T2D. The respective multivariable-adjusted mean values of daily step count, daily light-intensity, moderate-intensity, and moderate-to-vigorous-intensity PA were approximately 14%, 19%, and 22% lower in the men with T2D than in their non-T2D counterparts. However, women with T2D accumulated a greater number of steps per day than women without T2D. Only 59.2% of the adults with T2D met the minimum recommended level of PA (WHO and IDF), compared to 74.2% of adults without T2D (p<0.05). After adjusting for potential confounders, participants with T2D experienced 50.0% significantly lower odds of achieving PA recommendations. Conclusions: Vietnamese men with T2D were less physically active than those without T2D, and adults with T2D were less likely to meet PA guidelines. The results suggest a need for integrating PA into the self-management of this chronic condition.

• Safety and Health at Work
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• v.10 no.3
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• pp.254-259
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• 2019

Background: This cross-sectional study assessed the sleep quality using the ActiGraph and investigated the relationship between the parameters of sleep assessment and the type of shift work in Korean firefighters. Methods: The participants were 359 firefighters: 65 day workers (control group) and 294 shift workers (shift work group: 77 firefighters with 3-day shift, 72 firefighters with 6-day shift, 65 firefighters with 9-day shift, and 80 firefighters with 21-day shift). Sleep assessments were performed using the ActiGraph (wGT3X-BT) for 24 hours during day shift (control and shift work group) and night shift and rest day (shift work group). The participants recorded bed time and sleep hours during the measurement period. Results: Sleep efficiency, total sleep time, and percentage of wake after sleep onset during night work were lower in the shift work group than control group (p < 0.05). Sleep efficiency decreased in night shift and increased in rest day, whereas wake after sleep onset increased in night shift and decreased in rest day (p < 0.05). Among shift work groups, sleep efficiency of 6-day shift was higher in day shift, and sleep efficiency of 21-day shift was lower in night shift than other shift groups (p < 0.05). Conclusion: We found that the sleep quality in night shift of the shift work group was poorer than the control group. As to the type of shift work, sleep quality was good in 6-day shift and poor in 21-day shift. Thus, fast rotating shift such as 6-day shift may be recommended to improve the sleep quality of the firefighters.