• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.171-179
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• 2005

It is essential to understand the role of wall lining materials when they are exposed to a fire from an ignition source. Full-scale test methods permit an assessment of the performance of a wall lining material. Fire growth models have been developed due to the costly expense associated with full-scale testing. The models require heat flux maps from the ignition burner flame as input data. Work to date was impeded by a lack of detailed spatial characterization of the heat flux maps due to the use of limited instrumentation. To increase the power of fire modeling, accurate and detailed heat flux maps from the ignition burner are essential. High level spatial resolution for surface temperature can be provided from an infrared camera. The objective of this study was to develop a heat flux mapping procedure for a room test burner flame to a wall configuration with surface temperature information taken from an infrared camera. A prototype experiment was performed using the ISO 9705 test burner to demonstrate the developed heat flux mapping procedure. The results of the experiment allow the heat flux and spatial resolutions of the method to be determined and compared to the methods currently available.

• Nutrition Research and Practice
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• v.12 no.3
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• pp.199-207
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• 2018

BACKGROUND/OBJECTIVES: Fermented Laminaria japonica (FL), a type sea tangle used as a functional food ingredient, has been reported to possess cognitive improving properties that may aid in the treatment of common neurodegenerative disorders, such as dementia. MATERIALS/METHODS: We examined the effects of FL on scopolamine (Sco)- and ethanol (EtOH)-induced hippocampus-dependent memory impairment, using the Passive avoidance (PA) and Morris water maze (MWM) tests. To examine the underlying mechanisms associated with neuroprotective effects, we analyzed acetylcholine (ACh) and acetylcholinesterase (AChE) activity, brain tissue expression of muscarinic acetylcholine receptor (mAChR), cAMP response element binding protein (CREB) and extracellular signal-regulated kinases 1/2 (ERK1/2), and immunohistochemical analysis, in the hippocampus of mice, compared to current drug therapy intervention. Biochemical blood analysis was carried out to determine the effects of FL on alanine transaminase (ALT), aspartate transaminase (AST), and triglyceride (TG) and total cholesterol (TC) levels. 7 groups (n = 10) consisted of a control (CON), 3 Sco-induced dementia and 3 EtOH-induced dementia groups, with both dementia group types containing an untreated group (Sco and EtOH); a positive control, orally administered donepezil (Dpz) (4mg/kg) (Sco + Dpz and EtOH + Dpz); and an FL (50 mg/kg) treatment group (Sco + FL50 and EtOH + FL50), orally administered over the 4-week experimental period. RESULTS: FL50 significantly reduced EtOH-induced increase in AST and ALT levels. FL50 treatment reduced EtOH-impaired step-through latency time in the PA test, and Sco- and EtOH-induced dementia escape latency times in the MWM test. Moreover, anticholinergic effects of Sco and EtOH on the brain were reversed by FL50, through the attenuation of AChE activity and elevation of ACh concentration. FL50 elevated ERK1/2 protein expression and increased p-CREB (ser133) in hippocampus brain tissue, according to Western blot and immunohistochemistry analysis, respectively. CONCLUSION: Overall, these results suggest that FL may be considered an efficacious intervention for Sco- and EtOH-induced dementia, in terms of reversing cognitive impairment and neuroplastic dysfunction.

• Nutrition Research and Practice
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• v.12 no.3
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• pp.191-198
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• 2018

BACKGROUD/OBJECTIVES: Neuroinflammation plays critical role in neurodegenerative disorders, such as Alzheimer's disease (AD). We investigated the effect of three licorice varieties, Glycyrhiza uralensis, G. glabra, and Shinwongam (SW) on a mouse model of inflammation-induced memory and cognitive deficit. MATERIALS/METHODS: C57BL/6 mice were injected with lipopolysaccharide (LPS; 2.5 mg/kg, intraperitoneally) and orally administrated G. uralensis, G. glabra, and SW extract (150 mg/kg/day). SW, a new species of licorice in Korea, was combined with G. uralensis and G. glabra. Behavioral tests, including the T-maze, novel object recognition and Morris water maze, were carried out to assess learning and memory. In addition, the expressions of inflammation-related proteins in brain tissue were measured by western blotting. RESULTS: There was a significant decrease in spatial and objective recognition memory in LPS-induced cognitive impairment group, as measured by the T-maze and novel object recognition test; however, the administration of licorice ameliorated these deficits. In addition, licorice-treated groups exhibited improved learning and memory ability in the Morris water maze. Furthermore, LPS-injected mice had up-regulated pro-inflammatory proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2, interleukin-6, via activation of toll like receptor 4 (TLR4) and nuclear factor-kappa B ($NF{\kappa}B$) pathways in the brain. However, these were attenuated by following administration of the three licorice varieties. Interestingly, the SW-administered group showed greater inhibition of iNOS and TLR4 when compared with the other licorice varieties. Furthermore, there was a significant increase in the expression of brain-derived neurotrophic factor (BDNF) in the brain of LPS-induced cognitively impaired mice that were administered licorice, with the greatest effect following SW treatment. CONCLUSIONS: The three licorice varieties ameliorated the inflammation-induced cognitive dysfunction by down-regulating inflammatory proteins and up-regulating BDNF. These results suggest that licorice, in particular SW, could be potential therapeutic agents against cognitive impairment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.61-69
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• 2020

This study examined the braking characteristics of a heavy haul freight train with P4a distribution valves applied to domestic high-speed freight trains. A freight train was composed of 50 cars, which is twice the normal operation. A braking test was performed to confirm the characteristics of the braking of a heavy haul. The brake cylinder pressures were measured for emergency and service braking on the 1st, 10th, 20th, 30th, and 50th cars. Because the brake signal is transmitted to the pressure through the braking tube connected to the end of the train, the rear vehicle is braking later than the vehicle ahead. Therefore, it is necessary to predict the brake pressures in all cars in a train to supplement the results of the limited tests and calculate the braking distance. The pressure in each car was determined using empirical models of linear interpolation, stepwise, and exponential models, which provided reliable information. The predictive results of the empirical models were compared with the measured results, and the exponential model was predicted relatively accurately. These results are expected to contribute to the safe operation of heavy haul freight trains and can be used to predict the braking distance and calculate the level of impact between vehicles during braking.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1292-1303
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• 2015

Jeju province is the highest area about obesity(1st), alcohol consumption(2nd) and male smoking(2nd) among sixteen Korean provinces by the report of Statistics Korea: 2013 community health survey. Therefore, it is assumed that the incidence rate of colon, liver, lung and breast cancer can be high. The purpose of this study is to test these cancer's incidence and mortality trends and compare comparability with national average. The Joinpoint regression model and permutation tests for identifying changes and parallelism in trend were used to test registered data at Jeju Regional Cancer Registry from 1999 to 2012. In male colorectal cancer, Average Age Percent Change(AAPC) of Age-Standardized incidence Rate(ASR) was 8.4% per year(p-value<.000) and the hypothesis of parallelism with Korean male average was rejected because of steep increasing of Jeju male patients' AAPC(p-value=.047). In male liver cancer, AAPC of ASR was -2.98 % per year(p-value<.000) and parallelism with Korean male average was rejected because of sluggish decreasing of Jeju(p-value=.026). In male lung cancer, the ASR parallelism with Korean male average was rejected(p-value=.009) because Jeju patients APC(4.37% per year) was increased during 2006~2012. This study demonstrates that AAPC and Trends of male colon, male lung and male liver were difference from national average. Further studies are needed to understand its causes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1786-1795
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• 2011

The trajectory control for omni-directional mobile robot is not easy. Especially, the tracking control which system uncertainty problem is included is much more difficult. This paper develops trajectory controller of 3-wheels omni-directional mobile robot using fuzzy multi-layered algorithm. The fuzzy control method is able to solve the problems of classical adaptive controller and conventional fuzzy adaptive controllers. It explains the architecture of a fuzzy adaptive controller using the robust property of a fuzzy controller. The basic idea of new adaptive control scheme is that an adaptive controller can be constructed with parallel combination of robust controllers. This new adaptive controller uses a fuzzy multi-layered architecture which has several independent fuzzy controllers in parallel, each with different robust stability area. Out of several independent fuzzy controllers, the most suited one is selected by a system identifier which observes variations in the controlled system parameter. This paper proposes a design procedure which can be carried out mathematically and systematically from the model of a controlled system; related mathematical theorems and their proofs are also given. Finally, the good performance of the developed mobile robot is confirmed through live tests of path control task.

• Korea journal of population studies
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• v.31 no.1
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• pp.127-146
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• 2008

Over the past four decades reproductive behavior has changed slowly in much of the African countries. The average total fertility rate has fallen from six or more to near five today. Between 1960 and 2000 the largest fertility decline occurred in such Northern African countries as Algeria, Libya, and Morocco. The mortality rate has decreased in most African countries. The purpose of this study is to review the pattern of demographic transition in African countries. At first, this study focuses on the fertility transition. In Africa, the total fertility rate has decreased from 6.59 to 4.85 between 1960 and 2000. The mortality rate has also decreased in most of African countries. It is also interesting to find that there is a clear difference among African countries. In terms of infant mortality rate, Libya shows the lowest rate(17), while Mali and Somalia remain still high rate(142 and 133, respectively). This study tests a path model in which infant mortality rate acts as an intermediate variable between three socioeconomic variables and the fertility rate. The findings of this paper substantiate some of our hypotheses on the interrelationships among socioeconomic variables, infant mortality rate, and fertility rate. The result also shows the indirect effects of socioeconomic variables on fertility rate via infant mortality.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.369-375
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• 2011

Purpose: Many hemostatic agents and dressings have been tested with variable degree of success. Chitosan has a positive charge, it attracts red blood cells, which have a negative charge. Our goal is to test the efficacy of new developed chitosan-based hemostatic materials in providing durable hemostasis in a high-flow arterial wound model. Methods: We compared each group with SD rats motality tests and in vitro blood compatibility test by blood clotting index (BCI). We devided the SD rats into 6 groups (N =15) by type of hemostatic agents. A: 100% nonwoven chitosan (degree of the deacetylation: 90%). B: 50% N-acetylation on nonwoven of chitosan gel (degree of the deacetylation: 50%). C: 60% N-acetylation on nonwoven of chitosan ge (degree of the deacetylation: 40%)l. D: Cutanplast$^{(R)}$. E: HemCon$^{(R)}$ F: Gauze. In vivo test, a proximal arterial injury was created in unilateral femoral arteries of 90 anesthetized SD rats. Each materials was made same size and thickness then applied to the injury site for 3 minutes. In vitro test, we compared each group with BCI in human blood. Results: In vivo test, group A showed lower motality rate of 46% than any other groups, Group B and C showed lower motality rate of 60% than group D and E's motality rate of 66%. In vitro test, BCI of group A ($30.6{\pm}1.2$) and B ($29.3{\pm}1.0$) were showed nearly about group D ($29.1{\pm}1.8$) and E ($27.4{\pm}1.6$). Group C ($37.1{\pm}2.0$) showed higher BCI than group A and B, it means group C decreased blood clotting. Conclusion: In conclusion, this study suggests a newly developed chitosan-based hemostatic materials induced durable hemostasis and increased blood clotting, and are considered as effective biologic hemostatic agents.

• Land and Housing Review
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• v.2 no.4
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• pp.397-406
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• 2011

This research aims to develop various infill-systems for practically applying to long-life housing with 100-year durability and flexibility as a strategy for realizing sustainable residential environment. Especially, the developed infill-systems & technologies were concentrated to the mock-up house applied with the standard model of long-life housing, and their in-situ applicability by a phase, experts' consultation, and questionnaire survey were also evaluated. This research was executed to divide by 3 phases. In the First phase infill-systems for a housing unit of $84m^2$ exclusive use area as well as a support of whole structure and infill-systems including dry wall, and windows were constructed, and their in-situ applicability were evaluated. In the Second phase vertical integration of upper and lower housing units of $50m^2$ and $40m^2$ exclusive use area was investigated the first in domestic for 3 housing units of $50m^2$ exclusive use area. In addition, various infill-systems including the horizontal expansion of $50m^2$ and $10m^2$ exclusive use areas were also constructed and evaluated on their in-situ applicability. In the third phase diverse performance tests and field investigation for in-situ verifying of dry Ondol, developed this research, were executed to improve their practicability. Inner dry walls were taken apart, moved and re-constructed for verifying their practicability to investigate 3R-Reduce, Reuse and Recycle-realization too.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.77-81
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• 2007

Diagnostic performance of polymerase chain reaction (PCR) for detecting Dirofilaria immitis in dogs was evaluated when no gold standard test was employed. An enzyme-linked immunosorbent assay test kit (SnapTM, IDEXX, USA) with unknown parameters was also employed. The sensitivity and specificity of the PCR from two-population model were estimated by using both maximum likelihood using expectation-maximization (EM) algorithm and Bayesian method, assuming conditional independence between the two tests. A total of 266 samples, 133 samples in each trial, were randomly retrieved from the heartworm database records during the year 2002-2004 in a university animal hospital. These data originated from the test results of military dogs which were brought for routine medical check-up or testing for heartworm infection. When combined 2 trials, sensitivity and specificity of the PCR was 96.4-96.7% and 97.6-98.8% in EM and 94.4-94.8% and 97.1-98% in Bayesian. There were no statistical differences between estimates. This finding indicates that the PCR assay could be useful screening tool for detecting heartworm antigen in dogs. This study was provided further evidences that Bayesian approach is an alternative approach to draw better inference about the performance of a new diagnostic test in case when either gold test is not available.