• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.481-490
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• 2008

Reaction wheel is one of the actuators for spacecraft attitude control, which generates torque by changing an inertial rotor speed inside of the wheel. In order to generate required torque accurately and estimate an accurate angular momentum, wheel speed should be measured as close to the actual speed as possible. In this study, two conventional speed detection methods for high speed motor with digital tacho pulse (Elapsed-time method and Pulse-count method) and their resolutions are analyzed. For satellite attitude maneuvering and control, reaction wheel shall be operated in bi directional and low speed operation is sometimes needed for emergency case. Thus the bias error at low speed with constant acceleration (or deceleration) is also analysed. As a result, the speed detection error of elapsed-time method is largely influenced upon the high-speed clock frequency at high speed and largely effected on the number of tacho pulses used in elapsed time calculation at low speed, respectively.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.203-207
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• 2014

The present study was conducted to elucidate effects of heat, salt and hydrocolloid treatments on flying fish Cypselurus agoo roe analogs prepared using calcium alginate gel. The changes in size, sphericity and rupture strength of the analogs as affected by treatments of heat, sodium chloride and hydrocolloids were investigated. The size (mm), sphericity (%), and rupture strength (kPa) of the analogs were $2.2{\pm}0.1$, $98.2{\pm}0.2$, and $74.7{\pm}1.7$, respectively. When the analogs were heated at $95^{\circ}C$ in water, the size was slightly decreased. The rupture strength by curing with 2% sodium chloride was slightly increased. Sphericity didn't show significant differences by sodium chloride and heat treatment. The rupture strength of the analogs was slightly decreased by heat treatment, whereas remarkably decreased by curing with sodium chloride. In order to prevent a remarkable decrease in rupture strength of the analogs by curing with sodium chloride, the analogs were treated with hydrocolloids such as xanthan gum, gum guar, glucomannan, pectin and gelatin. The hydrocolloids treated analogs showed an increment in size and no significant changes in sphericity. On the other hand, the rupture strength of the hydrocolloids treated analogs exhibited remarkable increase than that of untreated ones.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.41.2-41.2
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• 2011

Recently, scaling down of ULSI (Ultra Large Scale Integration) circuit of CMOS (Complementary Metal Oxide Semiconductor) based electronic devices become much faster speed and smaller size than ever before. However, very narrow interconnect line width causes some drawbacks. For example, deposition of conformal and thin barrier is not easy moreover metallization process needs deposition of diffusion barrier and glue layer. Therefore, there is not enough space for copper filling process. In order to overcome these negative effects, simple process of copper metallization is required. In this research, Cu-V thin alloy film was formed by using RF magnetron sputter deposition system. Cu-V alloy film was deposited on the plane $SiO_2$/Si bi-layer substrate with smooth and uniform surface. Cu-V film thickness was about 50 nm. Cu-V layer was deposited at RT, 100, 150, 200, and $250^{\circ}C$. XRD, AFM, Hall measurement system, and XPS were used to analyze Cu-V thin film. For the barrier formation, Cu-V film was annealed at 200, 300, 400, 500, and $600^{\circ}C$ (1 hour). As a result, V-based thin interlayer between Cu-V film and $SiO_2$ dielectric layer was formed by itself with annealing. Thin interlayer was confirmed by TEM (Transmission Electron Microscope) analysis. Barrier thermal stability was tested with I-V (for measuring leakage current) and XRD analysis after 300, 400, 500, 600, and $700^{\circ}C$ (12 hour) annealing. With this research, over $500^{\circ}C$ annealed barrier has large leakage current. However V-based diffusion barrier annealed at $400^{\circ}C$ has good thermal stability. Thus, thermal stability of vanadium-based thin interlayer as diffusion barrier is good for copper interconnection.

• Korean Journal of Medicinal Crop Science
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• v.15 no.2
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• pp.95-99
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• 2007

The cost of conventional cultivation of ginseng (Panax ginseng C.A. Meyer) is very expensive, because shadow condition should be maintained during cultivation periods owing to inherently weak plant for high-temperature. Therefore, application of plant biotechnology may be possible to overcome these difficulties caused by conventional breeding of ginseng. Transgenic plants were produced via Agrobacterium tumefaciens Gv3101, both carrying the binary plasmid pBI121 mLPISO with nptII and Iso (isoprene synthase) gene. Integration of the transgenes into the P. ginseng nuclear genome was confirmed by PCR analysis using nptII primers and Iso primers. RT-PCR result also demonstrated the foreign isoprene synthase gene in three transgenic plant lines (T1, T3, and T5) which was expressed at the transcriptional level. When whole plants of transgenic ginseng were exposed to high temperature at $46^{\circ}C$ for 1 h, a non-transformed plant was wilted from heat shock, whereas a transgenic plant appeared to remain healthy. We suggest that the introduction of exogenous isoprene synthase is considered as alternative methods far generating thermotolerance ginseng.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.179-187
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• 2009

Five kinds of coumarin compounds were successfully purified from Angelica gigas Nakai by using recyclingpreparative HPLC and identified as decursin (1), decursinol angelate (2), 7-demethylsuberosine (3), marmesin (4), and decursinol (5) by NMR analyses. None of the purified compounds in ethanol showed DPPH radical scavenging activity, while the A. gigas extract (AGNEX) displayed a significant level of activity. Interestingly, compounds 3 in phosphate buffered saline (PBS) showed good $ABTS^+$ radical scavenging activity ($IC_{50}=8.1{\mu}g$/mL) as did compounds 4 and 5. The anti-inflammatory activities of the purified compounds were evaluated and compared using the NO concentration assay and western blot analysis on LPS-stimulated RAW 264.7 cells. NO production was significantly suppressed by all the compounds in a dose-dependent manner among which compounds 1, 2, and 3 showed very good activities with $IC_{50}$ values of 7.4, 6.5, and $7.6{\mu}g$/mL, respectively. Treatment with compounds 1-5 effectively suppressed the expression levels of iNOS, IL-1$\beta$, and COX-2, which are responsible for promoting the inflammatory process. Thus, the ethanol extract and coumarin compounds of A. gigas Nakai hold promise for use as potential anti-inflammatory agents.

• Journal of Korean Public Health Nursing
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• v.24 no.1
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• pp.39-48
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• 2010

Purpose: To examine the effects of a 36-week resistance training program on body composition, fitness and blood lipid profiles in the obese elderly. Method: fourteen subjects were assigned into the resistance training group. The 12-16 exercise sessions were performed for 60min with 15-25 repetitions twice per week for 36 weeks. Data were analyzed by paired t-test with SPSS version 12.0 for Windows. Results: Significant changes were evident in weight (t=5.983, p<.001), body mass index (t=5.922, p<.001), % body fat (t=3.480, p=.004), and fat free mass (t=-2.592, p=.022). Concerning exercises, no significance was noted for back scratch (t=-1.814, p=.093), but were for 2-min step (t=-3.075, p=.009), arm curl (t=-2.223, p=.045), chair stand (t=-3.671, p=.003), chair sit and reach (t=-2.508, p=.026), and 8-ft up and go (t=5.545, p<.001). No significant changes were evident in total cholesterol (t=1.189, p=.279), and total glucose (t=0.689, p=.517), while the change in high-density lipoprotein was significant (t=3.535, p=.012). Conclusion: The 36-week resistance training program enhanced body composition and physical fitness, but not blood lipid profiles in obese elderly subjects.

• Journal of Ocean Engineering and Technology
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• v.23 no.5
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• pp.71-78
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• 2009

In ship design or offshore structure design, the evaluation of buckling strength (or ultimate strength) is critical to the determination of scantling of stiffened plates. For this reason, it is useful to study the effect of applying different formula or the relationship between stiffened plate with buckling utilization factor (UF). It can facilitate a designer to decide how much the scantling should be reinforced or how much can be reduced for an optimal design. This paper conducts a comparative study for three buckling check methods; DNV-Ship-Rule, DNV-RP-C201, DNV-PULS. The capacity curves and 2D contour plot for utilization factors versus bi-axial in-plane stresses are compared. The contour plots of DNV-Ship-Rule and DNV-PULS show smoothly increasing trends of UF as the applied in-plane stresses increase, however that of DNV-RP-C201 shows rapidly increasing trend as the applied stresses go beyond transverse buckling stress. A sensitivity analysis is performed to investigate the influence level of each parameter of a stiffened plate on UF. Resulting from the analysis, plate thickness is identified to be the most affective parameter to UF regardless of the buckling check methods. Based on the addressed study, optimal designs for bottom plate of 165 K tanker corresponding to three formulas are compared with each other. DNV-PULS yields 1 mm and 2 mm less thickness than DNV-Ship-Rule and DNV-RP-C201, respectively.

• Journal of Convergence for Information Technology
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• v.7 no.3
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• pp.139-146
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• 2017

This study tries to examine the effect of parents' neglect on career identity, and prove the meditating effect of experience satisfaction and school adjustment between the two variables in the times of convergence. For the study, the data from the Korean Children and Youth Panel Survey was analyzed by utilizing the path analysis, and the number of subjects was 391 adolescents. The results are as follows: First, parents' neglect influenced negatively career identity. Second, experience satisfaction and school adjustment had a positive effect on experience satisfaction. Third, parents' neglect directly influenced career identity and its' effect was indirectly mediated by the subjects's experience satisfaction and school adjustment. Therefore, the result of the study can be utilized for theoretical implication and foundation for developing programs to increase career identity.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.1
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• pp.131-142
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• 2004

The purpose of this research was to investigate cytotoxity of Sunbanhwalmyungeum extract. Cytotoxity was determined by MTT assay method. After tumor cell lines(G361, BI6F10, MDA, A549) transplantation, the extracts of SunBangHwalMyungEum and its composition oriental medicines were administered, cytotoxity was measured by absorbance. The results were obtained as follows. 1. Sunbanhwalmyungeum extract and its composition oriental medicines extracts showed the concentration was higher, the more cytotoxity increased. 2. Both water and ethanol extracts of Sunbanhwalmyungeum showed excellent cytotoxity against G361, B16F10, MDA, A549 and high cytotoxity over 80$\%$ against G361, B16F10, MDA except A549 at the concentration of 1000ppm. 3. In water extract, Rhei Radix et Rhizoma, Gleditsiae Spina, Trichosanthis Radix, Glycyrrhizae Radix, Ledebouriellae Radix showed excellent cytotoxity. In ethanol extract, Gleditsiae Spina, Citri Pericarpium, Trichosanthis Radix, Paeoniae Radix Rubra, Myrrha showed excellent cytotoxity. 4. Rhei Radix et Rhizoma, Gleditsiae Spina, Trichosanthis Radix, Paeoniae Radix Rubra showed high cytotoxity in both water and ethanol extrats. 5. In water extract, Glycyrrhizae Radix, Ledebouriellae Radix, Myrrha showed high cytotoxity against A361, Lonicerae Flos, Olibanum, Fritillariae cirrhosae Bulbus, Paeoniae Radix Rubra, Manitis Squama against B16F10, Paeoniae Radix Rubra, Manitis Squama against MDA, Rhei Radix et Rhizoma, Angelicae gigantis Radix against A549. 6. In ethanol extract, Lonicerae Flos, Trichosanthis Radix showed high cytotoxity against G361, Rhei Radix et Rhizoma, Angelicae gigantis Radix, Gleditsiae Spina, Olibanum, Angelicae dahuricae Radix, Fritillariae cirrhosae Bulbus, Paeoniae Radix Rubra, Glycyrrhizae Radix, Ledebouriellae Radix, Myrrha against B16F10, Rhei Radix et Rhizoma, Manitis Squama against MDA, Citri Pericarpium, Manitis Squama against A549.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.178-178
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• 2010

With the scaling down of ULSI(Ultra Large Scale Integration) circuit of CMOS(Complementary Metal Oxide Semiconductor)based electronic devices, the electronic devices become more faster and smaller size that are promising field of semiconductor market. However, very narrow line width has some disadvantages. For example, because of narrow line width, deposition of conformal and thin barrier is difficult. Besides, proportion of barrier width is large, thus resistance is high. Conventional PVD(Physical Vapor Deposition) thin films are not able to gain a good quality and conformal layer. Hence, in order to get over these side effects, deposition of thin layer used of ALD(Atomic Layer Deposition) is important factor. Furthermore, it is essential that copper atomic diffusion into dielectric layer such as silicon oxide and hafnium oxide. If copper line is not surrounded by diffusion barrier, it cause the leakage current and devices degradation. There are some possible methods for improving the these secondary effects. In this study, TaNx, is used of Tertiarybutylimido tris (ethylamethlamino) tantalum (TBITEMAT), was deposited on the 24nm sized trench silicon oxide/silicon bi-layer substrate with good step coverage and high quality film using plasma enhanced atomic layer deposition (PEALD). And then copper was deposited on TaNx barrier using same deposition method. The thickness of TaNx was 4~5 nm. TaNx film was deposited the condition of under $300^{\circ}C$ and copper deposition temperature was under $120^{\circ}C$, and feeding time of TaNx and copper were 5 seconds and 5 seconds, relatively. Purge time of TaNx and copper films were 10 seconds and 6 seconds, relatively. XRD, TEM, AFM, I-V measurement(for testing leakage current and stability) were used to analyze this work. With this work, thin barrier layer(4~5nm) with deposited PEALD has good step coverage and good thermal stability. So the barrier properties of PEALD TaNx film are desirable for copper interconnection.