• Journal of Korea Port Economic Association
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• v.27 no.1
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• pp.213-234
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• 2011

The literature on efficiency of the maritime and shipping industry has typically focused on container ports and terminals. The study presented in this paper uses data envelopment analysis to evaluate ocean carriers based on financial and operational data from 2004 to 2007. A comparison is made up of the efficiency of global ocean carriers in efficiency of financial and operational performance respectively. A positive correlation is shown between the input and output data. In the static-efficiency analysis, we describe CCR, BCC and scale efficiency of Global Ocean Carriers in 2007. And we also provide about the stability and trend of their efficiency for four years (2004-2007) in the dynamic-efficiency analysis. The empirical results validate the necessity of restoring freight rates to facilitate the efficiency of the global ocean carriers supported by adjust of the supply of containership space. The study provides a basis for estimating the competitiveness of international shipping companies, for benchmarking best practice and for identifying the specific factors and causes of inefficiency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1149-1155
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• 1999

LEO(Low altitude Earth Orbit) Satellite systems have been utilized in the field of earth and scientific observation (cartography mission, ocean color monitoring, bioglogical coeanography, space environments observation by space physics sensor, and meteorological observation, atmospheric observation etc.), and the field of military (military communications and secret information, enemy reconnaissance etc.), and recently been developing in the field of mobile satellite commnication of GMPCS for commercial utilization. In Korea, KOMPSAT I satellite and ground system are been developing and planed to be lunched on October 1999 In this paper, the link budge of the TT&C system for LEO satellite is described and the relations between elevation angle and pass time of LEO satellite are calculated according to satellite moving. And the packet error rates of receiving data are derived three packet error rates(PER) of real-time(RT) mode, playback(PB) mode, and real-time and range tone(RT+RNG) mode are estimated according to pass time of satellite. The results of PER are the best at real-time and the worst at real-time mode and range mode at the all pass time of satellite. The average error free packet(EFP)s of real-time mode, playback mode, and real-time and range tone for the pass time of satellite are obtained as 99.999999%, 99.999912%, 99.995945% respectively. Therefore, transmission sequence of telemetry data are determined such as PER sequence according to pass time, namely, real-time, playback, and real-time and range mode.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.231-236
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• 2014

The present study was undertaken to evaluate the anti-hyperlipidemic activity of Albizzia julibrissin and Cassia tora L. extract mixtures in high fat diet-induced hyperlipidemic rats. In high-fat diet fed hyperlipidemic rats, oral treatment with Albizzia julibrissin and Cassia tora L. extracts resulted in decreased levels of total serum cholesterol and triglycerides, epididymal fat pad (EFP) weights, and activities of hepatic glucose-6-phosphate dehydrogenase (G6PDH) and malic enzyme, while the levels of feces production and high-density lipoprotein (HDL)-cholesterol were increased, compared with untreated control. Therefore, these results suggest that Albizzia julibrissin and Cassia tora L. extract mixtures can ameliorate hyperlipidemia.

• Journal of Nutrition and Health
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• v.36 no.10
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• pp.997-1012
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• 2003

This study was carried out to investigate the effect of whole grape, grape pomace and grape juice intake on cadmium (Cd) metabolism during aging in thirteen-month-old Sprague-Dawley male rats. One hundred and twenty rats weighing 548.8 $\pm$ 4.3 g were assigned to eight groups according to body weight and were raised for 3, 5 or 7 months on diets containing 2 ％ (w/w) dried powders of three different parts of the grape (Campbell Early) and 0.02 ％ (w/w) CdC12. Food intake tended to decrease with aging, and body weight and epididymal fat pad (EFP) weights of Cd-exposed groups were lower than those of Cd-free groups. Cadmium accumulated in the blood and tissues and Cd concentration was the lowest in the pomace group among Cd-exposed animals. Metallothionein (MT) concentration in the tissues increased through Cd administration. Grape diets, especially grape pomace diets, were effective in decreasing Cd absorption in the tissues by increasing Cd excretion through feces. The intake of grape pomace alleviated the decrease in bone density caused by Cd administration and prevented a decrease in glomerular filtration rates (GFR) with aging. Among the parts of grape, grape pomace, which had highest content of dietary fiber and flavonoids, was the most effective. The results of this study suggest the possibility of using grape pomace as a functional food material, a prospect that previously has been discarded.

• Wind and Structures
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• v.37 no.1
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• pp.15-23
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• 2023

The wake behavior of extended flat plate and serration in the trailing edge of S809 airfoil is presented in this experimental study using wind tunnel testing. The clustering of wind turbines in wind parks has recently been a pressing issue, due to the expected increase in power output and deciding the number of wind turbines to be installed. One of the prominent factors which influence the performance of the subsequent wind turbines is the downstream wake characteristics. A series of wind tunnel investigations were performed to assess the downstream near wake characteristics of the S809 airfoil at various angles of attack corresponding to the Reynolds Number Re = 2.02 × 105. These experimental results revealed the complex nature of the downstream near wake characteristics featuring substantial asymmetry arising out of the incoherent flow separations prevailing over the suction and the pressure sides of the airfoil. Based on the experimental results, it is found that the wake width and the downstream velocity ratio decrease with an increase in the angle of attack. Nonetheless, the dissipation length and downstream velocity ratio increases proportionally in the downstream direction. Additionally, attempts were made to understand the physical nature of the near wake characteristics at 1C, 2C, 3C and 4C downstream locations.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.61-69
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• 2001

EFP(Fitness For Purpose) type defect assessment methodologies based on ECA(Engineering Critical Analysis) have been established and are in use for the structural integrity evaluation of gas pipelines. ECA usually includes the fracture mechanics analysis, and it is assumed that the J-integral uniquely characterizes the crack-tip stress-strain field. However, it has been proven that the J-integral alone can not be sufficient to characterize the crack-tip field under low levels of constraint with a single parameter. Since pipeline structures are made of ductile material, locally loaded in tension, cracks may experience low level of constraint, and therefore, J-dominance will be lost. For this reason, the level of constraint must be quantified to establish a precise assessment procedure for pipeline defects. The objective of this paper is to investigate the fracture behavior of a crack in gas pipeline(KS D 3507) by quantifying the level of constraint. For this purpose, tensile tests and CTOD tests were performed at room temperature(24$\^{C}$) and low temperature(-40$\^{C}$) to obtain the material properties. J-Q analyses were performed for SENB and SENT specimens based on 2-D finite element analyses, in order to investigate the in-plane constraint effects on pipeline defects. For precise assessment of cracks, especially shallow cracks, in KS D 3507 pipeline, constraint effect must be considered.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.1
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• pp.13-20
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• 2013

In this study, oil palm biomass such as empty fruit bunch (EFP) and palm kernel shell (PKS) was used as raw materials for making pellets. EFB and PKS are valuable lignocellulosic biomass that can be used for various purposes. If EFB and PKS are used as alternative raw materials for making pellets instead of wood, wood could be saved for making pulps or other value-added products. In order to explore their combustion characteristics, EFB and PKS were analyzed using thermal gravimetric analyzer (TGA) with ultimate and proximate analyses. From the TGA results, thermal decomposition of EFB and PKS occurred in the range of 280 to $400^{\circ}C$ through devolatilization and combustion of fixed carbon. After $400^{\circ}C$, their combustion were stabilized with combustion of residual lignin and char. PKS contained more fixed carbons and less ash contents than EFB, which indicated that PKS could be more active in combustion than EFB.

• Journal of Nutrition and Health
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• v.37 no.7
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• pp.525-532
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• 2004

This study was performed to investigate the age-related changes of the lipid metabolism and thrombogenic capacity in Sprague-Dawley (SD) rats at the ages of 4, 8, 12, 16, 20 and 24 months old. Total lipid, triglyceride (TG) and total cholesterol in plasma and liver, HDL-cholesterol concentration, and eicosanoid contents in plasma were measured. Lipid peroxides were determined by the levels of thiobarbituric acid reactive substance (TBARS) in LDL fraction. Body weight was increased continuous until 16 months and decreased after 20 months. Epididymal fat pad (EFP) weight was increased continuously until 20 months and decreased at 24 months. Total lipid and TG concentrations in plasma were increased until 20 months and then rapidly decreased at 24 months but plasma cholesterol was increased continuously with aging. HDL-cholesterol level was increased continuously until 12 months, but decreased at 16 months and maintained there after. The TBARS levels in LDL fraction were the highest level at 24 months. Liver total lipid, TG, and total cholesterol concentrations were shown a tendency to increase with aging, and especially TG concentration was increased rapidly from 12 months to 16 months. Plasma thromboxane B$_2$ (TXB$_2$) and 6-keto-prostaglandin F$_1$ (6-keto-PGF$_1$) contents did not change with aging, but the ratio of TXB$_2$/6-keto-PGF$_1$ was increased with aging, especially from 8 to 12 months. These results showed that lipid levels in plasma and liver, TBARS levels in LDL fraction, and TXB$_2$/6-keto-PGF$_1$ ratio were increased with aging.

• Journal of Nutrition and Health
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• v.27 no.2
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• pp.119-126
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• 1994

The effect of diets(high fat, high fat high energy, pectin, cellulose) on adipocyte of epididymal fat pads were investigated in 70 male rats for 8 weeks. The rats were assigned to a control(C), high fat(HF) and high fat high energy(HFHE) group for 4 wks. During the next 4 wks, reassigned to one of three treatments (high fat, pectin supplemented, cellulose supplemented) in the HF group and one of three treatment (high fat high energy, pectin, cellulose) in the HFHE group. Therefore, the total experimental groups were 7 (C, HF, HF-P, HF-C, HFHE, HFHE-P, HFHE-C). Parameters evaluated and compared for each diet were body weight, total energy intake, feed efficiency ratio and weight changes in epididymal fat pads. The results are summarized as follows ; 1) There was no significant difference in body weight gain among the groups. 2) Total energy intake was higher in the C group than other groups. 3) Feed efficiency ratio (F.E.R) of the HF and HFHE groups were greater than C group(2, 4 weeks). However, there were no significant differences between the HF and HFHE groups. 4) Epididymal fat pads(EFP 100g/B.W) of the FH and HFHE groups were higher than C group (2, 4 weeks). However, there were no significant differences between the HF and HFHE groups. There was no significant difference in weight gain of epididymal fat pads among the groups(8 weeks). 5) Cell number and cell size of epididymal fat pads of the HF and HFHE groups were higher than the C group. The pectin and the cellulose supplementation groups decreased cell number and cell size of epididymal fat pads. Especially, the pectin supplementation group decreased than the cellulose supplementation in HFHE group. Therefore, we can concluded that the HF and the HFHE diet has no effect on the epididymal fat pads.

• The Plant Pathology Journal
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• v.37 no.2
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• pp.137-151
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• 2021

The present study describes the bacterial blight of walnut, caused by Xanthomonas arboricola pv. juglandis (Xaj) in the northern Gyeongbuk province, Korea. Disease symptoms that appear very similar to anthracnose symptoms were observed in walnut trees in June 2016. Pathogens were isolated from disease infected leaves, fruits, shoots, bud, flower bud of walnut, and cultured onto yeast dextrose carbonate agar plates. Isolated bacteria with bacterial blight symptoms were characterized for their nutrient utilization profiles using Biolog GN2 and Vitek 2. In addition, isolates were subjected to physiological, biochemical, and morphological characterizations. Furthermore, isolates were identified using 16S rDNA sequence analysis, and multi-locus sequence analysis using atpD, dnaK, efp, and rpoD. To confirm pathogenicity, leaves, fruits, and stems of 3-year-old walnut plants were inoculated with bacterial pathogen suspensions as a foliar spray. One week after inoculation, the gray spots on leaves and yellow halos around the spots were developed. Fruits and stems showed browning symptoms. The pathogen Xaj was re-isolated from all symptomatic tissues to fulfill Koch's postulates, while symptoms were not appeared on control plants. On the other hand, the symptoms were very similar to the symptoms of anthracnose caused by Colletotrichum gloeosporioides. When walnut plants were inoculated with combined pathogens of Xaj and C. gloeosporioides, disease symptoms were greater in comparison with when inoculated alone. Xaj population size was more in the month of April than March due to their dormancy in March, and sensitive to antibiotics such as oxytetracycline and streptomycin, while resistant to copper sulfate.