• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.4
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• pp.107-114
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• 2004

In this paper, a simple improved 8-node finite element for the finite element analysis of fibrous composite plates is presented by using the direct modification. We drive explicit expressions of shape functions for the 8-node element with bilinear element geometry, which is modified so that it can represent any quadratic fields in Cartesian coordinates. The refined first-order shear deformation theory is proposed, which results in parabolic through-thickness distribution of the transverse shear strains and stresses from the formulation based on the third-order shear deformation theory. It eliminates the need for shear correction factors in the first-order theory. This finite element is further improved by combined use of assumed strain, modified shape function, and refined first-order theory. To show the effectiveness of our simple modification on the 8-node finite elements, numerical studies are carried out the static, buckling and free vibration analysis of fibrous composite plates.

• Journal of Digital Convergence
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• v.19 no.1
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• pp.167-176
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• 2021

Incheon Port urgently requires designation of a free trade zone to pursue development linked with the port hinterland while promoting continuous growth of the port. This study aims to evaluate the optimal location and derive policy implications for the designation of a free trade zone and analyzed factors property divided by groups. This study used the Consistent Fuzzy Preference Relation (CFPR) analysis technique to derive a practical construction direction by quantifying and evaluating linguistic measures. As a result, the Incheon New Port hinterland showed the highest location competitiveness among the four candidate areas of Incheon New Port hinterland, Aam Logistics Complex 2, North Port hinterland, and Gyeongin Port hinterland. Among the eight evaluation factors consisting of qualitative and quantitative factors, the Incheon New Port hinterland ranked no. 1 in all the four qualitative factors and one quantitative factor and received the highest total score. Also, Group 1 presented 'possibility to attract tenant companies' as first. Group 2 was 'complex size' and Group 3 was also 'possibility to attract tenant companies'. This study has the implication for suggesting the factors and evaluation structure of Free Trade Zone. Future research requires detailed empirical studies, such as expanding the subject of study or selecting factors that reflect the interests of each group.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6D
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• pp.779-784
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• 2011

Freeway FFS (Free-Flow Speed) under the state of LOS (Level of Service) A has been regarded as a homogeneous state to all levels of traffic volume. The features of low-density FFS is served as the basic data for a decision on limited maximal speed, accident analysis, simulation modeling etc. A few researches for the macroscopic characteristics of design and operation speed have been reported, and any study for the microscopic features of freeway free-flow speed under the state of low density has not been done. Therefore, the characteristics of low-density FFS according to the level of traffic volume (1-3 veh/30 sec) and daily hour periods (0-5, 6-8, 9-11, 12-19, 20-23) is microscopically analyzed in this study with huge volume and speed data. It was found that speed distributions are changed and show different behaviors under the conditions of traffic volume levels and daily time periods. V85s (85th percentile speed) at early morning and night periods decrease when levels of traffic volume increase, whereas V85s at day time do not show considerable differences. Especially, FFSs of levels of traffic volume at early morning and night periods, despite low density, is analyzed as heterogeneity, but homogeneity at day time.

• Journal of the Korean Magnetics Society
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• v.19 no.2
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• pp.52-56
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• 2009

Interlayer coupling field, coercivity, magnetoresitance ratio, and magnetic sensitivity depending on the thickness of free CoFe layer for the CoFe/Cu/CoFe/IrMn multilayer are investigated. In case of CoFe layer of $30\;{\AA}$ thickness for the CoFe(t)/Cu($25\;{\AA}$)/CoFe($60\;{\AA}$)/IrMn($80\;{\AA}$) multilayer with ferromagnet/non-magnet/ferromagnet structure induced by IrMn layer, the lowest coercivity and the highest magnetic sensitivity, which is contained soft magnetic property, are observed. On the other side, in case of CoFe layer of $90\;{\AA}$ thickness, there are the highest coercivity and the lowest magnetic sensitivity. The fabricated CoFe($30\;{\AA}$)/Cu($25\;{\AA}$)/CoFe($60\;{\AA}$)]/IrMn($80\;{\AA}$) spin valve device with $2{\times}8{\mu}m^2$ patterning size are measured by two probe method, which is selected the sensing current as the longitudinal direction and the easy axis as the transversal direction. The measuring magntoresistance ratio and magnetic sensitivity of GMR-SV device having the soft magnetic property are 3.0% and 0.3%/Oe, respectively.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.573-578
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• 2012

A total of eleven Chinese cabbage accessions were used for microspore culture and were grown to take basal data. Based on the collected data, breeding materials were chosen to develop new improved Chinese cabbage cultivars. The range of microspore-derived embryoid taken from flower buds was 1.6 to 35.4 embryoids. The embryoids from IT26110 and IT26153 among the Chinese cabbages were more than 34 per flower bud. The viability rate after cold treatment was low from 0.2 to 11.7%. The range of fertility rate was 7.7 to 58.8% in general but the IT26118, IT26122, IT26128, IT26130, and IT26164 were more than 50%. The result of their seed production ability by selfing was 11.9 seeds per siliqua in IT26128 while the others were less than 10 seeds. In the microspore culture using parents of different hereditary, the number of embryoids, the number of plants, the rate of fertility and their pure seed production ability appeared to be very different in doubled haploid lines obtained from fertile plants of Chinese cabbage.

• Composites Research
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• v.14 no.1
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• pp.8-14
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• 2001

A simplified method for determining the three mode(I, II, III) components of the strain energy release rate of free-edge delaminations in composite laminates is proposed. The interlaminar stresses are evaluated using the interface moment and the interface shear forces which are obtained from the equilibrium equations at the interface between the adjacent layers. Deformation of an edge-delaminated laminate is analysed by using a generalized quasi-three dimensional classical laminated plate theory. The analysis provides closed-form expression for the three components of the strain energy release rate. The analyses are performed for composite laminates subjected to uniaxial tension, with free-edge delaminations located symmetrically and asymmetrically with respect to the laminate midplane. The analysis results agreed with a finite element solution using the virtual crack closure technique.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.124-130
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• 1992

This study aims at revealing the effects of the feeding mixed $\omega$-3 perilla oil and $\omega$-6 red pepper oil on fatty acid compositions of serum and platelet in rats. The diet administered to the male rats of Sprague - Dawley was composed of the peril1a oil containing about 60% $\omega$-3 linolenic acid as well as the red pepper oil with roughly 64% of $\omega$-6 linoleic acid. In the total fatty acid composition of serum lipid, SFA had no great significance among the groups, while MUFA ranged from 14.4% to 17.0% and PUFA stood from 48.0% to 53.0%. PUFA compositions of phospholipid, triglyceride and cholesteryl ester fractions, $C_{18:2}$ ($\omega$-6) was the highest in cholesteryl ester than the other components. In platelet's fatty arid composition, SFA were low in groups 2 (7.5% perilla oil＋2.5% red pepper oil) and 3 (5.0% perilla oil ＋5.0% red pepper oil), and the highest in group 5 (10% red pepper oil). MUFA stood the highest in group 3 and the lowest in group 5, while PUFA was the lowest in group 2. Ratio of EPA / AA was the highest in group 2, but group 5 was the lowest.t.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.315-326
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• 2002

This study was conducted to examine the effects of Red clay(Hwangto) as feed additives with 26 Hanwoo steers at two regions for 540 days from six to 24 months of age on feed efficiency, meat quantity and meat quality. Feeding trial 1 was conducted with two treatment groups by five heads/treatment which were T1(Control) and T2(Control+ad libitum Hwangto) at National Livestock Research Institute. Feeding trial 2 was conducted with four treatment groups by four heads/treatment which were T1(Control), T2(Control+2% Hwangto), T3(Control+5% Hwangto) and T4(Control+ad libitum Hwangto) at a private Hanwoo breeding farm. In feeding trial 1, average daily gains by growing, fattening, finishing and over-all periods were 0.572, 0.866, 0.869 and 0.769kg in T1, and 0.537, 0.904, 0.857 and 0.766kg in T2, respectively. Average daily gain for growing and finishing period was high in T1 but in T2 for fattening period, which were not statistically significant. Also concentrates and TDN intakes per kg gains were not statistically significant by treatments. In carcass characteristic, dressed carcass and red meat percentage were high in T1 but in T2 for retailed cut percentage without significant difference. The yield index and shear force was 69 and 70, 4.4 and 6.1 kg/$cm^2$ in T1 and T2, respectively. In palatability traits, the panel test scores of juiciness, tenderness and flavor were 4.08 and 4.64, 3.42 and 3.96, 4.58 and 4.80 in T1 and T2, respectively. which showed a tendency to improvement in Hwangto feeding groups. In feeding trial 2, the range of average daily gains were 0.656(T6) to 0.772(T3), 0.937(T6) to 1.009(T5), 0.592(T3) to 0.675kg(T6) in growing, fattening and finishing period, respectively. Although it was high in T3, T5 and T6 at growing, fattening and finishing period, respectively, it was not significantly different by treatments. The ranges of concentrates and TDN intakes per kg gains were 8.71 to 9.50(average 9.05) and 7.52 to 7.64kg(average 7.55kg), they all were lower in Hwangto feeding groups than in control about 4.5 to 8.3% and 1.2 to 1.6%, respectively. In carcass characteristics, back-fat thickness, loin eye muscle area and yield index were not difference by treatments, but marbling scores were high in T5 and T6 than in percent. Summarizing above results, it may be concluded that the use of unprocessed Hwangto as feed additives for growing-fattening steers seems to improve meat quality but not red meat quantity and feed efficiency, and may be required to feed ad libitum during the finishing period.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1167-1173
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• 2013

This study aimed to calculate the CFFs (critical flow functions) of a sonic nozzle bank with a 12-nozzle package within 1 s. Toward this end, the Helmholtz free energy of natural gas was formulated by using the AGA8-dc equation of state in a form without integral terms, and thereafter, thermodynamic properties such as the enthalpy, entropy, speed of sound, and heat capacity, which are used in CFF calculation, were derived in analytical form. As a result, the calculation time of CFFs was improved from 6.7 s in a previous study to 0.6 s per 12-nozzle package and kept almost constant regardless of the number of components in natural gas. Furthermore, it was confirmed that the calculated CFF values were in agreement with the results of a CFF international comparison test carried out under ISO management in 1998-1999.

• Land and Housing Review
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• v.3 no.4
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• pp.451-456
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• 2012

In this study, a numerical analysis to evaluate the reduction of seismic load due to pile group was performed and compared the peak ground acceleration(PGA) measured at free-field and foundation. The special attention was given to the amplification of seismic acceleration on the foundation due to the pile effects. The analysis considering pile effects was carried out for 4, 8 and 12 piles with same condition by PLAXIS 2D Dynamics. Based on the analysis results, it is found that the overall reduction in seismic load due to foundation and reduction rates are similar irrespective of pile numbers. This study gives a possibility for effective design of piled foundation by reducing seismic load about 20~25%.