• Journal of Labour Economics
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• v.24 no.1
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• pp.35-66
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• 2001

This study first attempted to measure the job instability of Korean labor market by exploiting the data sets of 1998 and 1999 Korean Labor Panels. In order to compare the degrees of job instability of Korea with the one of U.S., we followed the same empirical methods used by Jaeger and Stevens(1999), Neumark et al.(1999), Bemhardt et al.(1999) recently published in the Journal of Labor Economics (vol. 17). Our empirical results suggest that the job retention rate of the Korean labor market during the IMF economic crisis was decreased to the level that the U.S. labor market has never experienced during the past two decades. One noticeable point regarding our estimated four year retention rate is that it takes a form of plateau peaked around 9 and 15 tenure year, which is in sharp contrast with the four year retention rate of u.S. showing a monotonically decreasing tendency over tenure periods. The comparison of 2-year retention rates before and after the economic crisis suggests that job stabilities has been conspicuously aggravated especially for cohorts of long tenure, irregular job, old age, service and sales jobs.

• Journal of Astronomy and Space Sciences
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• v.22 no.4
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• pp.441-450
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• 2005

The organic material is one of the most popular material for the satellites and the spacecrafts in order to perform the thermal management, and to protect direct exposure from the space environment. The present paper observes material property changes of organic material under the space environment by using ground facilities. One of the representative organic thermal management material of satellites, 2 mil ITO(Indium Tin Oxide) coated aluminized KAPTON was selected for experiments. In order to investigate the single parametric effect of protons in space environment, MC-50 cyclotron system in KIRAMS(Korea Institute of Radiological and Medical Science) was utilized for the ion beam irradiation of protons and ion beam dose was set to the Very Large August 1972 EVENT model, the highest protons occurrence near the earth orbit in history. The energy of ion beam is fixed to 30MeV(mesa electron volt), observed average energy, and the equivalent irradiance time conditions were set to 1-year, 3-year, 5-year and 10-year exposure in space. The procedure of analyses includes the measurement of the ultimate tensile strength for the assessment of quantitative degradation in material properties, and the imaging analyses of crystalline transformation and damages on the exposed surface by FE-SEM(Field Emission Scanning Electron Spectroscopy) etc.

• Parasites, Hosts and Diseases
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• v.26 no.4
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• pp.255-262
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• 1988

An epidemiological study on brugian filariasis was carried out in endemic areas including Cheju Island in Korea, with a brief review of literatures. The results showed that the incidence among residents has remarkably decreased in Cheju Island, which was the main endemic area. Reviewing available informations on the prevalence of filariasis reported in recent years and also judging from the present socio·economic conditions which enable people to practice personal protection against mosquitos, it can be said with confidence that alariasis has almost disappeared from Cheju Island and inland areas. The disease is considered to remain at a low level of endemicity in Hugsan Islands. Certainly mass diethylcarbamasine (DEC) treatment carried out in Cheju Island in the 1960s and 1970s and remarkable economic growth followed by improved living standard and altered life-style of inhabitants could all have combined effects on the disappearance of this mosquito-borne disease in this island. If the present trends go on, the possibility of resurgence of filariasis in Cheju Island is hardly postulated.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.428-444
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• 2012

The species composition and seasonal variation of fisheries resources in Jinhae bay and Jinju bay, were studied using shrimp beam trawl through a year of 2010. During the study period, a total of 117 species were collected in Jinhae bay. Species included were 63 species in Pisces and 24 in Crustacea. And a total of 106 species were collected in Jinju bay. Species included were 57 species in Pisces and 31 in Crustacea. The dominant species were Zoarces gilli, Crangon hakodatei and Oratosquilla oratoria in Jinhae bay, and Crangon hakodatei, Leiognathus nuchalis and Charybdis bimaculata in Jinju bay. The samples were mainly grouped according to the location and season on the SOM. Group 1 with sample sites in Jinju bay, was characterized by high values of Parapenaeopsis tenella, Leiognathus nuchalis and Hexagrammos otakii. Group 2 with sample sites in April, were dominant Crangon hakodatei and Luidia quinaria. The samples in Group 3 were high values of Charybdis bimaculata and Pleuronichthys cornutus. Group 4 with sample sites in Jinhae bay, was characterized by high densities of Zoarces gilli and Pholis fangi. The dominant species, Crangon hakodatei, were catched egg-bearing females until June. Zoarces gilli and Leiognathus nuchalis were presented small size individuals during study period. It represented that study area is an important role in spawning and nursery ground for fisheries resources.

• Journal of Gifted/Talented Education
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• v.22 no.3
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• pp.779-800
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• 2012

This study is to understand gifted students' suicidal ideation and its related variables among gifted students. For this, this study explores the relationship between maladaptive perfectionism of gifted students and suicidal ideation, confirming mediating effects of depression and academic stress. For the study 320 middle school students who were identified as the gifted at a gifted education center affiliated with the university. The results are summarized as follows. First, the fit of measurement model was found to be ${\chi}^2$=228.571(df=110, p=.000), CFI=.972, TLI=.966, RMSEA=.058, indicating most of fit indexes were acceptable. Second, suicidal ideation was found a significant positive relationship with maladaptive perfectionism, depression, academic stress. Third, as a result of examining path coefficient, it was found to be influenced significantly by all of the path from maladaptive perfectionism to depression and academic stress, the path from depression to suicidal ideation, the path from academic stress to suicidal ideation. However, the path from maladaptive perfectionism to suicidal ideation was found to be statistically insignificant. Fourth, the result showed that depression and academic stress worked as complete mediators between maladaptive perfectionism and suicidal ideation. These findings give useful information about affective aspects of gifted adolescents in hard circumstances. The results of the study will be helpful in devising consultation and educational programs for the gifted who are in danger of suicide.

• Sijohaknonchong
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• v.30
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• pp.165-188
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• 2009

This paper is an analysis about Ahn, Jasan's theory of Sijo. He comprehended that Korean classical poetry is not a literary genre written in letters but a music genre sung orally, because he minutely investigated old books under the situation without preconceptions. Ahn, who had a thorough knowledge on our native music or literature, had an exact recognition about Sijo. He had analyzed existence of Sijo after commenting Sijo's true nature, whenever he discuss. His attitude was possible for his recognition like that. The first step of Ahn, Jasan's theory of Sijo is source of Sijo searched for identity of Sijo. Generic source, metrics, poetical idea, and history are written well in the paper. Establishment of Sijo's poetic identity is second step's discourse about Ahn's theory of Sijo, the contents are integrated in his book Poetics of Sijo poetry. He became to discuss Sijo as a regular poetry, even in this book. Especially a minute discussion about theory of Sijo's phrase and lines was accomplished in this time, theory of metrics based on meter and rhythm was a core discussion of this time too. Although his scholarly opinions are not refined comparing to the scholars of later ages, we can say that his opinions clearly worked a role of exemplary precedent. His opinions were other scholars ahead, nevertheless he had been neglected by researchers for not belonging to major group against his will. For this reason, I think Ahn's status in history of Sijo study has to be readjusted.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.79-90
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• 1997

Monthly samples of surf zone fish at Taechon Beach were collected by a beach seine from June 1995 to May 1996, and analyzed for the species composition, abundance and community structure. Of 26 species identified, Favonigobius gymnauchen, Leiognathus nuchalis, Sillago japonica and Kareius bicoloratus predominated in abundance. In spring, the adults of resident species were dominated. A large number of juveniles of pelagic or demersal fish occupied the surf zone from summer to autumn. Fish numbers and biomass were low in winter. The species composition of the present study showed a similar seasonal trend to that obtained in 1984-85. However, demersal fish such as K. bicoloratus, Repomucenus lunatus, Johnius belengerii and Enedrias fangi, and L. nuchalis were increased, while pelagic fish such as Thrissa koreana, Sardinella zunasi and Konosirus punctatus were diminished. These changes seemed to be related to sedimentation of fine particles for demersal fish and subsequent increase in turbidity for pelagic fish after reclamation in the bay.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.169-178
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• 2018

Gyeongin Port has low awareness, insufficient hinterland infrastructures, and lower competitiveness. So, in this study, we conducted Fuzzy-IPA analysis reflecting the recognition of the consignor companies that are using Gyeongin port to suggest present practical improvement measures for the activation of the operation of Gyeongin port hereafter. As a result of the analysis, three factors, that is, cargo loading/unloading/storage costs, port facility fees, and incentive and support were derived as priority investment areas. Three factors, that is, cargo safety, infrastructure equipment, and inland transportation costs were derived as the areas for maintenance strengthening and factors related to cargo handling and service factors were derived as areas for maintenance of the status quo and areas for gradual improvement, respectively. This study is significant in that it analyzed the recognition of the consignor companies that are using Gyeongin port using a quantifying method and suggested realizable measures for activation based on the results of the analysis. In future studies, the frequency of ships' calling at the port and measures to diversify the sea routes should be additionally reflected on the analysis.

• Journal of the Korean Vacuum Society
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• v.17 no.4
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• pp.311-316
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• 2008

Since the presence of the chemical impurities and defect at surfaces and interfaces greatly influence the properties of various semiconductor devices, an unambiguous chemical characterization of the metal and semiconductor surfaces become more important in the view of the miniaturization of the devices toward nano scale. Among the various conventional surface characterization tools, Electron-induced Auger Electron Spectroscopy (EAES), X-ray Photoelectron Spectroscopy (XPS) and Secondary Electron Ion Mass Spectroscopy (SIMS) are being used for the identification of the surface chemical impurities. Recently, a novel surface characterizaion technique, Positron-annihilation induced Auger Electron Spectroscopy (PAES) is introduced to provide a unique method for the analysis of the elemental composition of the top-most atomic layer. In PAES, monoenergetic positron of a few eV are implanted to the surface under study and these positrons become thermalized near the surface. A fraction of the thermalized positron trapped at the surface state annihilate with the neighboring core-level electrons, creating core-hole excitations, which initiate the Auger process with the emission of Auger electrons almost simultaneously with the emission of annihilating gamma-rays. The energy of electrons is generally determined by employing ExB energy selector, which shows a poor resolution of $6{\sim}10eV$. In this paper, time-of-flight system is employed to measure the electrons energy with an enhanced energy resolution. The experimental result is compared with simulation results in the case of both linear (with retarding tube) and reflected TOF systems.

• Membrane Journal
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• v.21 no.1
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• pp.30-38
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• 2011

Composite membranes based on sulfonated poly(aryl ether) sulfone (SPAES) with different sulfated zirconia nanoparticles ($s-ZrO_2$) ratio are synthesized and investigated for the improvement of the hydration and the proton conductivity at high temperature and no humidification for fuel cell applications. X-ray diffraction technique is employed to characterize the structure and the size of $s-ZrO_2$ nanoparticles. The sulfation effect of $s-ZrO_2$ nanoparticles is verified by FT-IR analysis. The properties of the SPAES composite membranes with the various $s-ZrO_2$ ratio are evaluated by ion exchange capacity and water content. The proton conductivities of the composite membranes are estimated at room temperature with full hydration and at the various high temperature without external humidification. The composite membrane with 5 wt% $s-ZrO_2$ shows the highest proton conductivity. The proton conductivities are $0.9292\;S\;cm^{-1}$ at room temperature with full hydration and $0.0018\;S\;cm^{-1}$ at $120^{\circ}C$ without external humidification, respectively.