• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.429-437
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• 1999

A mathematical model was established for estimating changes in pressure and volume of permeable kimchi packages. The model comprises the CO2 gas production from kimchi and permeation of O2, CO2 and N2 through the permeable film or sheet. Using the developed model, the effects of various packaging variables on the pressure and volume changes were analyzed for rigid and flexible packag es of kimchi(3% salt content) at 15oC, and then effect of storage temperature was also looked into. In case of rigid pack of 400g, using the plastic sheet of high CO2 permeability and initial vacuumizing can help to relieve the problem of pressure build up. The lower fill weight can further reduce the pressure, but will result in higher packaging cost. For the flexible package of 3 kg, highly permeable films such as low density polyethylene(LDPE) and polypropylene can reduce the volume expansion. Higher ratio of CO2 permeability to O2 and N2 permeabilities are effective in reducing the volume expansion. Increased surface area cannot contribute to reduction of volume expansion for highly permeable flexible packages of kimchi. For the impermeable packages, pressure and volume at over ripening stage (acidity 1.0%) increase with decreased temperature, while those at optimum ripening stage(acidity 0.6%) change little with temperature. Pressure of permeable rigid LDPE package increases with tem perature at any ripening stage, and temperature affects the volume of flexible LDPE package very slightly. Experimental verification of the present results and package design with economical consid eration are needed as a next step for practical application.

• Journal of the Korean Institute of Navigation
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• v.18 no.2
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• pp.91-109
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• 1994

Technological and organisational changes in transport system have introduced new dimension into port system development and inter-port competition. The quality of service now required by the customer is costly and not easily provided by small shipping companies and small ports. It has been suggested that in the future container shipping may be concentrated by space-sharing arrangements or actual mergers into the hands of a few mega-operators with the investment potential to provide total logistics networks. In order to compete effectively, high load factors will be essential and port concentration inevitable. A fa-voured few ports will become the load centres and other ports will assume a secondary feeder role. In this study, three questions are raised and attempts are made to answer them : (a) what is the new role of ports today ; (b) why should ports be engaged in this new role ; and (c) how can ports play this new role. In short, a modern port should be a service centre and a logistic platform for international trade and transport-a third generation port. Ports, in particular, have to make every effort to be competitive in the cost and quality of services and to make the port a transport and distribution service centre. For most ports, this is not an option but a must ; an essential requirement for survival in this win or lose situation. The best way to win is to maintain a close contact with port users, listen to them, discuss with them, help them and satisfy them. That is port marketing. Starting from the findings of port marketing, it is es-sential to work out appropriate development plans and marketing targets and to improve port competitive-ness. As an alternative method, a port competitiveness model is suggested, which may help port managers to make appropriate improvements.

• Journal of Ginseng Research
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• v.18 no.1
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• pp.1-9
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• 1994

Sprague-Dawley rats were given freely with 15% ethanol (control) and 15% ethanol containing (1) 0.1% ginseng saponin, (2) 0.02% ginsenoside $Rb_1$, and (3) $Rg_1$ (tests) instead of water for 7 days and aldehyde dehydrogenase (ALDH) and monoamine oxidase (MAO) activity in different regions of brain were examined. In control group, total ALDH activity with indoleacetaldehyde and acetaldehyde as substrate in all different regions was lower than that of normal group except in the hippocampus. The inhibitory effect on the activity was prominent in the corpus striatum and was not in the hippocampus. However, low-$K_m$ ALDH activity in all different regions was much lower than that of normal group. A considerable decrease in mitochondria ALDH activity in cerebellum and striatum was also observed in control group. In test groups total, low-$K_m$, and mitochondria AkDH activities in all different regions were higher than those in control group. Although ALDH activity in the striatum of test group was higher than control group, it was relatively depressed as compared with normal. There was not found a remarkable difference in extent of stimulating effect on the AkDH activity according to the ginseng saponin components. When biogenic aldehydes were used as substrate, ALDH activity with 3,4-dihydroxy-phenylacetaldehyde (DOPAL) in all brain regions of control group was lower than that using 5-hydroxy-indoleacetaldehyde (HIAL) and 3,4-dihydroxyphenylglycolaldehyde (NORAL) as substrate. In control group, ALDH activity with biogenic aldehydes above mentioned was markedly inhibited in the striatum contrary to other regions. The higher ALDH activity with biogenic aldehydes in test group than in control was found in the striatum, cerebrum, and cerebellum. MAO activity in the cerebellum was inhibited in control group and slightly increased in test group. The results of present study suggest that the corpus striatum is significantly affected by ethanol exposure while the hippocampus is not and that ginseng saponin fraction and ginsenosid es might have a preventive effect against depression of brain ALDH activity by chronic administration of ethanol.

• Journal of Environmental Health Sciences
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• v.47 no.3
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• pp.205-226
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• 2021

Objectives: Biomonitoring programs have been widely implemented in the field of environmental health, both in Korea and worldwide. Recently, it has been suggested that the storage, management, and utilization of biosamples collected from biomonitoring programs should be organized based on a biobank system. Therefore, we attempted to review the current status of representative biomonitoring programs and biobank systems that have been implemented in Korea and in other countries. Methods: We searched for bio-samples collected in domestic and foreign biomonitoring programs and their applications. For this, we referred to research papers, homepages hosted by biomonitoring programs, and project reports. We also checked information for biobanks related with biomonitoring programs, including the operating systems, facilities, technologies, and regulations of biobanks. Results: We summarized six domestic and 32 foreign biomonitoring programs. These biomonitoring programs collected bio-samples to determine the relationship between environmental chemicals and diseases. Domestically, bio-samples from KoNEHS, KorSEP, MOCEH, KoCHENS, and KorEHS-C were stored at -80℃ in a deep freezer at the National Institute of Environmental Research, while KNHANES samples were stored at Korea Biobank, which has a stabilized biobanking system with a well-established database. Nine foreign biomonitoring programs (JECS, China-NHBP, CKB, CHMS, NHANES, GerES, Germaan ESB, MoBa, and UK Biobank) were ongoing for large populations. Among them, CKB, GermanESB, and UK biobank have been maintained for at least 10 years with their own biomonitoring programs as well as advanced systems for the safe storage of bio-samples. Conclusion: Currently on-going biobanks have devoted considerable efforts to managing bio-samples for public purposes. The preceding domestic and foreign biomonitoring programs and biobanks will be great references for constructing biobank facilities and systems for environmental public health in Korea in the future.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.3-3
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• 2001

Recently TiN, TiAlN, CrN hardcoatings have adapted many industrial application such as die, mold and cutting tools because of good wear resistant and thermal stability. However, in terms of high speed process, general hard coatings have been limited by oxidation and thermal hardness drop. Especially in the case of PCB drill, high speed cutting and without lubricant process condition have not adapted these coatings until now. Therefore more recently, superhard nanocomposite coating which have superhard and good thermal stability have developed. In previous works, WC-TiAlN new nanocomposite film was investigated by cathodic arc ion plating system. Control of AI concentration, WC-TiAlN multi layer composite coating with controlled microstructure was carried out and provides additional enhancement of mechanical properties as well as oxidation resistance at elevated temperature. It is noted that microhardness ofWC-TiA1N multi layer composite coating increased up to 50 Gpa and got thermal stability about $900^{\circ}C$. In this study WC-TiAlN nanocomposite coating was deposited on PCB drill for enhancement of life time. The parameter was A1 concentration and plasma cleaning time for edge sharpness maintaining. The characteristic of WC-TiAlN film formation and wear behaviors are discussed with data from AlES, XRD, EDS and SEM analysis. Through field test, enhancement of life time for PCB drill was measured.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.263-270
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• 1996

Twenty two patients underwent total anatomic correction of complete atrioventricular septal defect associated with other cardiac anomalies between July 1986 and December 1994. Age ranged from 6 months to 11 years(mean 49.6 $\pm$ 35.8 months), and they were composed of 7 males and 15 females. Combined major cardiac anomalies were tetralogy of Fallot(TOF) in 11 cases, double outlet of right ventricle (DORV) in 6 ca es, and transposition of great arteries (TGA) in 5 cases. Down's syndrome was associated in 5 patients with TOF and 1 patient with DORV. They were classified as Rastelli type A in 3 patients, B in 2 patients, and C in 17 patients. Modified Blalock-Taussig shunt was performed.in 5 patients and Waterston shunt in 1 patient as a palliative procedure. There were 7 perioperative deaths(31.8%) and the causes were pump weaning failure, low cardiac output, acute renal failure, persistant pulmonary hypertension and hypertensive crisis, and sepsis. Reoperations were performed in 4 cases to repair atrioventricular valvular regurgitation or to relieve the right ventricular outflow tract (RVOT) or pulmonary arterial stenosis. One late death was due to aspiration pneumonia. Second reoperation was necessary for progressive worsening of left atrioventricular regurgitation and RVOT stenosis in one patient. Fourteen survived patients were followed up for a mean of 66.0 $\pm$ 26.7months and all of them w re NYHA functional class I or II.

• Parasites, Hosts and Diseases
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• v.55 no.3
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• pp.295-304
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• 2017

Opisthorchis viverrini infection induces chronic inflammation, and a minor proportion of infected individuals develop advanced periductal fibrosis (APF) and cholangiocarcinoma (CCA). Inflammatory cytokines and/or their gene polymorphisms may link to these biliary pathologies. We therefore investigated associations among cytokine gene polymorphisms and cytokine production in 510 Thai cases infected with O. viverrini who presented with APF+ or APF-, as established by abdominal ultrasonography as well as in patients diagnosed with CCA. Levels of pro-inflammatory and anti-inflammatory cytokines were determined in culture supernatants after stimulation of peripheral blood mononuclear cells (PBMCs) with O. viverrini excretory-secretory (ES) products. Pro-inflammatory cytokines, IL-$1{\beta}$, IL-6, IFN-${\gamma}$, LT-${\alpha}$, and TNF-${\alpha}$ were significantly increased in CCA patients compared with non-CCA (APF- and APF+) cases. Polymorphisms in genes encoding IL-$1{\beta}$-511C/T, IL-6-174G/C, IFN-${\gamma}$+874T/A, LT-${\alpha}$+252A/G, and TNF-${\alpha}$-308G/A were then investigated by using PCR-RFLP or allele specific-PCR (AS-PCR) analyses. In the CCA cases, LT-${\alpha}$+252A/G and TNF-${\alpha}$-308G/A heterozygous and homozygous variants showed significantly higher levels of these cytokines than the wild type. By contrast, levels of cytokines in wild type of IFN-${\gamma}$+874T/A were significantly higher than the variants in CCA cases. IFN-${\gamma}$+874T/A polymorphisms were associated with advanced periductal fibrosis, whereas IL-6-174G/C polymorphisms were associated with CCA. To our knowledge, these findings provide the first demonstration that O. viverrini infected individuals carrying several specific cytokine gene polymorphisms are susceptible to develop fibrosis and CCA.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.314-322
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• 2017

Purpose: This study was conducted to investigate the hot air drying characteristics of squash slices depending on the drying conditions (input air velocity, input air temperature, and sample thickness). Methods: The developed drying system was equipped with a controllable air blower and electric finned heater, drying chamber, and ventilation fan. Squash (summer squash called Korean zucchini) samples were cut into slices of two different thicknesses (5 and 10 mm). These were then dried at two different input air temperatures (60 and $70^{\circ}C$) and air velocities (5 and 7 m/s). Six well-known drying models were tested to describe the experimental drying data. A non-linear regression analysis was applied to determine model constants and statistical indices such as the coefficient of determination ($R^2$), reduced chi-square (${\chi}^2$), and root mean square error (RMSE). In addition, the effective moisture diffusivity ($D_{eff}$) was estimated based on the curve of ln(MR) versus drying time. Results: The results clearly showed that drying time decreased with an increase in input air temperature. Slice thickness also affected the drying time. Air velocity had a greater influence on drying time at $70^{\circ}C$ than at $60^{\circ}C$ for both thicknesses. All drying models accurately described the drying curve of squash slices regardless of slice thickness and drying conditions; the Modified Henderson and Pabis model had the best performance with the highest R2 and the lowest RMSE values. The effective moisture diffusivity ($D_{eff}$) changes, obtained from Fick's diffusion method, were between $1.67{\times}10^{-10}$ and $7.01{\times}10^{-10}m^2/s$. The moisture diffusivity was increased with an increase in input air temperature, velocity, and thickness. Conclusions: The drying time of squash slices varied depending on input temperature, velocity, and thickness of slices. The further study is necessary to figure out optimal drying condition for squash slices with retaining its original quality.

• Atmosphere
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• v.26 no.1
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• pp.127-140
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• 2016

In this study, the correlations between AST850 and precipitation, and those between WDT and precipitation in the Yeongdong coastal region under the direct/indirect influence of the expansion of cP (continental polar air mass) high were quantitatively analyzed based on the winter season data for the last 20 years, according to surface pressure patterns such as Type 1 (cP high expansion type), Type 2 (cP high expansion + trough type), Type 4 (South trough type), and Type 5 (East Sea trough type). Here, AST850 represents 'sea surface temperature minus temperature on 850 hPa level' and WDT represents 'a speed of 1000 hPa wind projected onto a certain wind direction times precipitation duration in hour'. First, the correlation coefficients between AST850 and precipitation in Type 1, Type 2, and Type 5 cases were 0.253, 0.384, and 0.398 respectively, indicating that a tendency of increasing precipitation linearly with the value of AST850 is slightly presented. In the case of Type 4, however, the coefficient was -0.15, representing almost no linear correlation between AST850 and precipitation. In the correlation between WDT and precipitation, there was the largest correlation coefficient (0.464) between WDT along a direction of $90^{\circ}$ and at EN1 in Type 1 cases. In the case of Type 2, there was the largest correlation coefficient (0.767) between WDT along a direction of $67.5^{\circ}$ and at ES1. In the case of Type 4, there was the largest correlation coefficient (0.559) between WDT along a direction of $22.5^{\circ}$ and at EN2. Finally, in the case of Type 5, there was the largest correlation coefficient (0.945) between WDT along a direction of $315^{\circ}$ and at SE1, representing the largest coefficient among the types. It was found that surface wind directions with the highest correlations to precipitation in the Yeongdong coastal area on winter season were varied according to surface pressure patterns, and that the correlations between WDT and precipitation were higher than those between AST850 and precipitation.

• Journal of the Korean association of regional geographers
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• v.18 no.3
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• pp.336-350
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• 2012

Cette $\acute{e}$tude a pour objectif d'analyser et d'expliquer le g$\acute{e}$osite de l'$\hat{I}$le de Geum-o pour connaitre les caract$\acute{e}$ristiques de cette r$\acute{e}$gion du point de vue $\acute{e}$cologique, historique et culturel $\grave{a}$ partir de ses ressources g$\acute{e}$omorphiques et g$\acute{e}$ologiques. Il y a plusieurs ressources g$\acute{e}$otouristiques sur $\hat{I}$le de Geum - o: la falaise de 'Miyeokneolbang' et 'Shinseondae'; la plage de Gigpo; la falaise et la caverne marine de 'Gualbaramtong'; le tombolo et l'$\hat{I}$le reli$\acute{e}$e $\grave{a}$ la terre de Choungsan; la coul$\acute{e}$e de roches de Jangji; la plage de cailloux de Jangji; le lieu des tuf et des andesite de la c$\hat{o}$te orientale. On a g$\acute{e}$n$\acute{e}$ralement d$\acute{e}$velopp$\acute{e}$ la couche s$\acute{e}$dimentaire et les roches volcaniques li$\acute{e}$es $\grave{a}$ la derni$\grave{e}$re p$\acute{e}$riode du m$\acute{e}$sozo$\ddot{i}$que. Une route g$\acute{e}$otouristique part de l'embarcad$\grave{e}$re de Hamgoumi sur l'$\hat{I}$le de Geum-o et continue du Nord-Ouest jusqu'au Sud-Est l'autre route part de la c$\hat{o}$te Est et continue en suivant la c$\hat{o}$te orientale. Nous proposons des panneaux d'explication g$\acute{e}$otouristique de Janji centr$\acute{e}$s sur la coul$\acute{e}$e de roches.