• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.91-96
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• 2001

In this paper, an investigation was performed on the dynamic interlaminar fracture toughness of CFRP(carbon filber rein-forcement plastics). Specimens used in this experiments are CF/PEEK laminated plates. In this experiments, Split Hopkin-sons Bar(SHPE) tes was apply to dynamic and notched flexure test. The model II fracture toughness of each unidirectional CFRP was estimated by the analyzed deflection of the specimen and J-integral with the measured impulsive load and reac-tions at the supported points. As an experimental results the vibration amplitude of [$0^{\circ}_10 /F_4 0^{\circ}_10 $] j-aminates appear more than that of [$0^{\circ}_10 /F_2 0^{\circ}_10 $ laminates for the j-integral and displacement velocity at a measuring point. Also, it is thought that the dynamic fracture toughness of two kind specimen(CF/PEEK) with the crease of displacement velocity becomes great at a measuring point with in the range of measurement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.675-678
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• 2001

In this paper, an investigation was performed on the dynamic interlaminar fracture toughness of CFRP(carbon fiber reinforcement plastics). Specimens used in this experiment are CF/EPOXY laminated plates. In this experiments, Split Hopkinson s Bar test was applied to dynamic and notched flexure test. The mode II fracture toughness of each unidirectional CFRP was estimated by the analyzed deflection of the specimen and J-integral with the measured impulsive load and reactions at the supported points. As an experimental result, the vibration amplitude of 〔$0_{10}F_4/0_{10}$〕laminates appear more than that of 〔0_{10}/F_2/0_{10}$〕laminates for the J-integral and displacement velocity at a measuring point. Also, it is thought that the dynamic fracture toughness of two kind specimen with the increase of displacement velocity becomes great at a measuring point with in range of measurement.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.79-79
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• 2010

To investigate whether the present-day active galaxies follow the same black hole mass vs. stellar velocity dispersion (MBH-$\sigma*$) relation as quiescent galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which black hole masses were measured via reverberation mapping. We measured stellar velocity dispersions from high S/N optical spectra centered on the Ca II triplet region (${\sim}8500^{\circ}A$), obtained at the Keck, Palomar, and Lick Observatories. For two objects, in which the Ca II triplet region was contaminated by nuclear emission, we used high-quality H-band spectra obtained with the OH-Suppressing Infrared Imaging Spectrograph and laser-guide star adaptive optics at the Keck-II Telescope. Combining our new measurements with data from the literature, we assemble a sample of 24 active galaxies with stellar velocity dispersions and reverberation MBH in the range of black hole mass 106< MBH /$M{\odot}$ < 109,toobtainthefirstreverberationmappingconstraintsontheslopeandintrinsicscatteroftheMBH- $\sigma*$ relation of active galaxies. Assuming a constant virial coefficient f for the reverberation MBH, we find a slope ${\beta}=3.55{\pm}0.60$ and the intrinsic scatter ${\sigma}int=0.43{\pm}0.08$ dex in the relation log (MBH/M${\odot}$)=$\alpha+\beta$ log(${\sigma}*$/200 km s-1), which are consistent with those found for quiescent galaxies. We derive an updated value of the virial coefficient f by finding the value which places the reverberation masses in best agreement with the MBH - $\sigma*$ relation of quiescent galaxies; using the quiescent MBH - $\sigma*$ relation determined by Gultekin et al. we find log f=0.72+0.09 (or $0.71{\pm}0.10$) with an intrinsic scatter of $0.44{\pm}0.07$ (or 0.46+0.07) dex. No correlations between f and parameters connected to the physics of accretion (such as the Eddington ratio or line-shape measurements) are found. The uncertainty of the virial coefficient remains one of the main sources of the uncertainty in black hole mass determination using reverberation mapping, and therefore also in single-epoch spectroscopic estimates of black hole masses in active galaxies.

• Ocean and Polar Research
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• v.28 no.4
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• pp.395-405
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• 2006

We measured the fugacity of $CO_2$ $(fCO_2)$, temperature, salinity, nutrients and chlorophyll a in the surface water of the western North Pacific $(4^{\circ}30'{\sim}33^{\circ}10'N,\;144^{\circ}20'{\sim}127^{\circ}35'E)$ in September 2002. There were zonally several major currents which have characteristics of specific temperature and salinity (NECC, North Equatorial Counter Current; NEC, North Equatorial Current; Kuroshio etc.). Surface $fCO_2$ distribution was clearly distinguished into two groups, tropical and subtropical areas of which boundary was $20^{\circ}N$. In the tropical Int surface $fCO_2$ was mainly controlled by temperature, while in the subtropical area, surface $fCO_2$ was dependent on total inorganic carbon contents. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-0.69{\sim}0.79 mmole\;m^{-2}day^{-1}$. In the area of AE (Anticyclonic Eddy), SM(Southern Mixed region) and NM (Northern Mixed region), the ocean acted as a weak source of $CO_2$ $(0.6{\sim}0.79 mmole\; m^{-2}day^{-1})$. In NECC, NEC, Kuroshio and ECS (East China Sea), however, the fluxes were estimated to be $-0.3mmole\; m^{-2}day^{-1})$ for the first three regions and $-1.2mmole\; m^{-2}day^{-1})$ for ECS respectively, indicating that these areas acted as sinks of $CO_2$. The average air-sea flux in the entire study area was $0.15mmole\;m^{-2}day^{-1})$, implying that the western North Pacific was a weak source of $CO_2$ during the study period.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.98-102
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• 2008

Relationships between total length (TL) and fecundity, body weight and fecundity, ovary length and fecundity, and ovary weight and fecundity of hilsa shad, Tenualosa ilisha Hamilton, collected from Kuakata, Patuakhali, Bangladesh, were studied. During the sampling period, the fecundity of hilsa was found to range from 169,000 (fish TL=28.0cm, weight=250g) to 1,088,000 (fish TL=40.5cm, weight=955g) with a mean of $520{\pm}53{\times}1,000$. The number of eggs per gram of ovary for samples collected from the anterior, middle, and posterior regions of the ovary were also recorded, but no significant variation was found among ovary regions at the 5% level of significance. Fecundity increased with fish TL and weight. The regression equations obtained in arithmetic forms of relationships between TL and fecundity (F), body weight (BW) and fecundity, ovary length (OL) and fecundity, and ovary weight (OW) and fecundity were $F=-887,896+40,511{\times}TL(r=0.85)$, $F=67,577+755.44{\times}BW(r=0.85)$, $F=-562,070+87,668{\times}OL(r=0.75)$ and $F=124,815+6,596.7{\times}OW (r=0.84)$, respectively. The relationships between fecundity and TL, body weight, ovary length, and ovary weight were linear, and the 'r' values were highly significant (p<0.01). These results provide valuable data for the restoration of hilsa resources, which are economically important but have shown reduced productivity in nations adjacent to the Bay of Bengal.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.1-13
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• 2007

In order to evaluate the local site effects at two town fortress areas in Korea where stone parapets were col-lapsed by historical earthquakes, site characteristics were assessed using site investigations such as borehole drillings and seismic tests. Equivalent-linear site response analyses were conducted based on the shear ways velocity ($V_s$) profiles and geotechnical characteristics determined from site investigations. The study sites are categorized as site classes C and B according to the mean $V_s$ to 30 m ranging from 500 to 850 m/s, and their site periods are distributed in the short period range of 0.06 to 0.16 sec, which contains the natural period of fortress wall and stone parapet. From the results of site response analyses in the study areas, for site class C indicating most of site conditions, contrary to site class B, the short-period (0.1-0.5 sec) and mid-period (0.4-2.0 sec) site coefficients, $F_a$ and $F_v$ specified in the Korean seismic design guide, underestimate the ground motion in short-period band and overestimate the ground motion in mid-period band, respectively, due to the high amplification in short period range, which represent the site-specific seismic response characteristics. These site-specific response characteristics indicate the potential of resonance in fortress walls during earthquake and furthermore could strongly affect the collapse of parapets resulted from seismic events in historical records.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.183-190
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• 2007

The site effects of seismic stations were evaluated by conducting a simultaneous inversion of the stochastic point-source ground-motion model (STGM model; Boore, 2003) parameters based on the accumulated dataset of horizontal shear-wave Fourier spectra. A model parameter $K_0$ and frequency-dependent site amplification function A(f) were used to express the site effects. Once after a H/V ratio of the Fourier spectra was used as an initial estimate of A(f) for the inversion, the final A(f) which is considered to be the result of combined effect of the crustal amplification and loca lsite effects was calculated by averaging the log residuals at the site from the inversion and adding the mean log residual to the H/V ratio. The seismic stations were classified into five classes according to $logA_{1-10}^{max}$(f), the maximum level of the site amplification function in the range of 1 Hz < f < 10 Hz, i.e., A: $logA_{1-10}^{max}$(f) < 0.2, B: 0.2 $\leq$ $logA_{1-10}^{max}$(f) < 0.4, C: 0.4 $\leq$ $logA_{1-10}^{max}$(f) < 0.6, D: 0.6 $\leq$ $logA_{1-10}^{max}$(f) < 0.8, E: 0.8 $\leq$ $logA_{1-10}^{max}$(f). Implication of the classified result was supported by observing a shift of the dominant frequency of average A(f) for each classified stations as the class changes. Change of site classes after moving seismic stations to a better site condition was successfully described by the result of the station classification. In addition, the observed PGA (Peak Ground Acceleration)-values for two recent moderate earthquakes were well classified according to the proposed station classes.

• Phonetics and Speech Sciences
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• v.2 no.1
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• pp.33-39
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• 2010

This study investigates the effect of pitch range reset in Korean listeners' processing of syntactically ambiguous participle structures. Unlike Japanese and English,in Korean, the downtrend or the reset of pitch range does not consistently differentiate Accentual Phrases (AP), a lower level of phrasing, from Intonational Phrases (IP), a higher level of phrasing. Therefore, we explore Korean listeners' comprehension patterns for syntactically ambiguous speech strings varying in 1) the relative height of F0 peaks across prosodic units, and 2) the types of prosodic phrasing, to see whether pitch range reset informs the recovery of syntactic structure even though it is not reflected in the intonational hierarchy in Korean. The results show that the hierarchical level of prosodic phrasing affects the parsing pattern of syntactic ambiguity. The pitch range reset also cued the location of syntactic boundaries, but this effect was confined to phrases across AP.

• Korea Journal of Hospital Management
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• v.22 no.2
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• pp.28-43
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• 2017

The purpose of this study was to investigate the influence of professional self-concept and interpersonal relations on nursing competence of clinical nurses. This study was conducted as a descriptive cross sectional survey with 182 nurses who work at a tertiary hospital which has over 1,000 beds, located in Gyeounggi - do. The data was collected from October 11th, 2016 to October 28th, 2016. The main findings of this study were as follows. The mean score for professional self-concept was $2.65{\pm}0.29$ points in the range of 1 point to 4 points. And interpersonal relations was an average of $3.55{\pm}0.35$ points in the range of 1 point to 5 points. Nursing competence was an average of $2.65{\pm}0.39$ points in the range of 1 point to 4 points. Professional self-concept and interpersonal relations were positively correlated with nursing competence. Nursing competence was differed from clinical career(F=10.518, p<.001), working unit(F=4.139, p=.018), educational background(F=6.542, p=.002), and satisfaction on nursing(F=6.326, p<.001). The regression model with clinical career, working unit, educational background, satisfaction on nursing, 3 sub domain of professional self-concept(professional practice, satisfaction, communication), and interpersonal relation was statistically significant (F=31.94, p<.001). And this model could explain 51.5% of nursing competency(Adj R2=.515). Especially, professional practice(${\beta}=.532$, p<.001) of professional self-concept, interpersonal relations(${\beta}=.223$, p<.001), clinical career(${\beta}=.169$, p<.001), working unit: ICU (${\beta}=.169$, p<.05) were identified the factors influencing on nursing competence. Therefore, improving clinical nurses' nursing competence can be achieved with broad approach that includes improvements in professional self-concept and interpersonal relations. And also, working unit, and clinical career should be considered to develop the actual program for nursing competence, too.

• Journal of Korean Academy of Nursing
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• v.28 no.2
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• pp.329-343
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• 1998

This study was designed to identify the relationship between perceived pain, family support and quality of life in patients with ankylosing spondylitis. The purpose of this study was to contribute to the theoretical understanding of the relationship of these three variables and eventually to more effective adaptation of patients to their situation. The subjects for this study were the 68 patients who had been diagnosed with ankylosing spondylitis and registered as out-patients in the Rheumatism Center of one university hospital in Seoul. The data were collected during the period from October 10, 1997 to December 20, 1997, Pain was measured using the perceived pain scale(VAS : Visual Analog Scale)developed by Calm(1993), family support using the scale developed by Kang Hyun Suk (1985) and Quality of Life using the scale developed by Ro Yoo Ja(1988). The data were analyzed by descriptive statistics, Frequencies, Pearson correlation coefficient, using the SPSS program. The results of this can be summarized as followings. 1. The mean perceived pain score was 5. 13 with a range of 2 to 10. 2. The mean perceived family support score was 41.08$\pm$5.34 with a range of 20 to 50. 3. The mean perceived quality of life score was 134.07$\pm$19.82 with a range of 83 to 176. 4. Significant statistical difference was found between family support and quality of life (r=.331, p<0.001). A significant negative statistical difference was found between the family support and quality of life and pain(r=-.250, p<0.05, r=-.460, p<0.001). 5. General characteristics related to pain were exercise (t=4.72, p<0.0006). 6. General characteristics related to family support were age(F=2.65, p<0.0246), educational level (F=2.84, p<0.0282) and exercise (t=3.24, p<0.0452). 7. General characteristics related to quality of life were educational level (F=3.03, p<0.0392) and exercise (t=3.12, p<0.0465). It was found that the higher the level perceived pain, the lower the degree of perceived family support and the quality of life. It was also found that the higher the degree of perceived family support, the higher the degree of perceived quality of life. Accordingly, the conclusions from this study are that reduction of pain is achieved through the family support. Therefore, it is proposed that family support is an appropriate nursing intervention to improve the quality of life of patients with ankylosing spondylitis.