• Journal of Astronomy and Space Sciences
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• v.11 no.1
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• pp.53-70
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• 1994

The Korean sounding rockets(KSR420S-1, -2) equipped with ozone detectors have b3en launched at An-heung, Chungchungnam-do, on June 4 and September 1, 1993, respectively. The ozone detector is used to measure the attenuation of solar UV radiation for various frequency bands in the stratosphere, to obtain vertical profiles of the ozone number density in the stratosphere. They confirm that the maximum ozone densities occur near 25 km, which is quite consistent with the mean value in the mid-latitude region. Our results from KSR420S-1 and -2 are compared with the other observation data from the Dobson spectrophotometer at Yonsei Univ., the LIDAR at Kyunghee Univ., the SBUV from Nimbus satellite, and the TOVS from NOAA satellite, which were performed simultaneously with the sounding rocket experiments.

• Journal of Information Display
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• v.9 no.4
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• pp.21-29
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• 2008

We studied both the wavelength and intensity dependent photo-responses (photofield-effect) in amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs). During the a-IGZO TFT illumination with the wavelength range from $460\sim660$ nm (visible range), the off-state drain current $(I_{DS_off})$ only slightly increased while a large increase was observed for the wavelength below 400 nm. The observed results are consistent with the optical gap of $\sim$3.05eV extracted from the absorption measurement. The a-IGZO TFT properties under monochromatic illumination ($\lambda$=420nm) with different intensity was also investigated and $I_{DS_off}$ was found to increase with the light intensity. Throughout the study, the field-effect mobility $(\mu_{eff})$ is almost unchanged. But due to photo-generated charge trapping, a negative threshold voltage $(V_{th})$ shift is observed. The mathematical analysis of the photofield-effect suggests that a highly efficient UV photocurrent conversion process in TFT off-region takes place. Finally, a-IGZO mid-gap density-of-states (DOS) was extracted and is more than an order of magnitude lower than reported value for hydrogenated amorphous silicon (a-Si:H), which can explain a good switching properties observed for a-IGZO TFTs.

• Journal of Species Research
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• v.6 no.2
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• pp.177-180
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• 2017

Diploscapter coronatus (Cobb, 1893) Cobb, 1913 was first reported on oriental melon (Cucumis melo vars. makuwa Makino) roots from plastic film houses, Gyeongsangbuk-do, Andong, Korea (latitude $N36^{\circ}33^{\prime}$. longitude $E128^{\circ}29^{\prime}$). Diploscapter coronatus is most similar to D. pachys. Species in the genus Diploscapter have a visibly annulated cuticle. The stoma of D. coronatus is 1.5 times longer than the lip region width. The pharyngeal corpus is clearly separated from the isthmus and the vulva is situated around the mid-body. However, it differed by higher ratio of "a", filiform tail and had relatively blunt labial hooks. The Korean population is well matched and within the range of D. coronatus as described from Iran and Ethiopia in de Man's of L, b, c, c', and V. Female length, however, varied between populations: the Ethiopia population female length is longer than in the Korea population (396.4 vs 427.0) while females in the Iran population are smaller than in the Korea population (396.4 vs 350.0). Nematode size may vary due to environmental conditions such as food sources. The position of excretory pores in the Korean population were shorter 53.9-72.5 than in other populations (67-82 and 70-89). Males were uncommon. Males in the Korean population are smaller than females but larger(356.0) than males in the Indian population (306.0).

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.81-91
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• 2005

A new species of draconematid nematode, Paradraconema jejuense n. sp., is described from the shallow sublittoral coarse sediments of Jeju Island, Korea. Paradraconema jejuense n. sp. is most similar to P. antarcticum Allen and Noffsinger, 1978 in having similar habitus (long slender body) and amphideal fovea (doubled elongate spiral in male and circular spiral in female), but is distinguished by the following characteristics: larger number of posterior sublateral adhesion tubes (10 in male and 11-12 in female) and subventral adhesion tubes (16 in male and 17-18 in female), fewer cephalic acathiform setae on rostrum (a pair of small cephalic acathiform setae in both sexes), the absence of eye-spots, and the presence of a differentiated lateral field in mid-body region. This is the first taxonomic report on Paradraconema species from Korea.

• International Journal of Oral Biology
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• v.33 no.3
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• pp.97-103
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• 2008

The present study investigated the role of peripheral group I, II, and III metabotropic glutamate receptors (mGluRs) in mustard oil (MO)-induced nociceptive response in the masseter muscles of lightly anesthetized rats. Experiments were carried out on male Sprague-Dawley rats weighing 300-350 gm. After initial anesthesia with sodium pentobarbital (40 mg/kg, i.p.), one femoral vein was cannulated and connected to an infusion pump for intravenous infusion of sodium pentobarbital. The rate of infusion was adjusted to provide a constant level of anesthesia. MO (30 ${\mu}L$) was injected into the mid-region of the left masseter muscle via a 30-gauge needle over 10 seconds. After 30 mL injection of 5, 10, 15, or 20% MO into the masseter muscle, total number of hindpaw-shaking behavior was monitored. Intramuscular administration of MO significantly produced hindpawshaking behavior in a dose-dependent manner, as compared with the vehicle (mineral oil)-treated group. Intramuscular pretreatment with 10 or 100 ng DHPG, a group I mGluRs agonist, enhanced MO-induced hindpaw-shaking behavior, while APDC (20 or 200 ${\mu}g$), a group II mGluRs agonist, or L-AP4 (2 ${\mu}g$), a group III mGluRs agonist, significantly reduced MO-induced nociceptive behavior. The antinociception, produced by group II or III mGluRs agonists, was abolished by pretreatment with LY341495, a group II mGluRs antagonist, or CPPG, a group III mGluRs antagonist, res-pectively. Based on these observations, peripheral mGluRs differentially modulated MO-induced nociceptive behavior response in the craniofacial muscle pain and peripheral group II and III mGluRs agonists could be used in treatment of craniofacial muscle nociception.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.41-51
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• 2005

Using three-dimensional non-hydrostatical numerical model with one way double nesting technique, atmo­spheric circulation in the mountainous coastal region in summer was investigated from August 13 through 15, 1995. During the day, synoptic westerly wind blows over Mt. Mishrung in the west of a coastal city, Sokcho toward the East Sea, while simultaneously, easterly upslope wind combined with both valley wind from plain (coast) toward mountain and sea-breeze from sea toward inland coast blows toward the top of the mountain. Two different directional wind systems confront each other in the mid of eastern slope of the mountain and the upslope wind goes up to the height over 2 km, becoming an easterly return flow in the upper level over the sea and making sea-breeze front with two kinds of sea-breeze circulations of a small one in the coast and a large one in the open sea. Convective boundary layer is developed with a thickness of about 1km over the ground in the upwind side of the mountain in the west and a thickness of thermal internal boundary layer from the coast along the eastern slope of the mountain is only confined to less than 200 m. On the other hand, after sunset, no prohibition of upslope wind generated during the day and downward wind combined with mountain wind from mountain towardplain and land-breeze from land toward under nocturnal radiative cooling of the ground surfaces should intensify westerly downslope wind, resulting in the formation of wind storm. As the wind storm moving down along the eastern slop causes the development of internal gravity waves with hydraulic jump motion in the coast, bounding up toward the upper level of the coastal sea, atmospheric circulation with both onshore and offshore winds like sea-breeze circulation forms in the coastal sea within 70 km until midnight and after that, westerly wind prevails in the coast and open seas.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.227-235
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• 2006

Changes of the species diversity and development of vegetation structure during abandoned field succession after shifting cultivation were investigated in Pyoungchang, Gangwon-Do, Korea. The height of top layer tended to increase rapidly during the earlier successional stages and stabilize in the later successional stage. The heights of top layer in the 10, 20, 50 and 80 year old-field were 4, 9, 18 and 18 m, respectively. In this region, thirty five year after abandonment need for the development to the normal forest formed by 4 stratum structure, tree, sub-tree, shrub and herb layer. Among the vegetation values, Ivc showed a tendency to increase logarithmically, and Hcl a tendency to increase linearly during abandoned field succession. Species diversity showed the peak in mid-successional stages ($10{\sim}20$ year old-field) and declined slightly thereafter. Species diversity was correlated closely with the species richness than the evenness. The most woody species established in the earlier stage ($2{\sim}6$ year old-field) and turned over their dominance step by step during succession. These results support the IFC model proposed by Egler (1954).

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.64.2-64.2
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• 2016

Optical variability is one way to probe the nature of the central engine of AGN at smaller linear scales and previous studies have shown that optical variability is more prevalent at longer timescales and at shorter wavelengths. Especially, intra-night variability can be explained through the damped random walk model but small samples and inhomogeneous data have made constraining this model hard. To understand the properties and physical mechanism of optical variability, we are performing the KMTNet Active Nuclei Variability Survey (KANVaS). Test data of KMTNet in the COSMOS field was obtained over 2 separate nights during 2015, in B, V, R, and I bands. Each night was composed of 5 and 9 epochs with ~30 min cadence. To find AGN in the COSMOS field, we applied multi-wavelength selection methods. Different selection methods means we are looking different region in unification model of AGN, and 100~120, 400~500, 50~100 number of AGN are detected in X-ray, mid-infrared, and radio selection of AGN, respectively. We performed image convolution to reflect seeing fluctuation, then differential photometry between the selected AGN and nearby stars to achieve photometric uncertainty ~0.01mag. We employed one of the standard time-series analysis tools to identify variable AGN, chi-square test. Preliminarily results indicate that intra-night variability is found for X-ray selected, Type1 AGN are 23.6%, 26.4%, 21.3% and 20.7% in the B, V, R, and I band, respectively. The majority of the identified variable AGN are classified as Type 1 AGN, with only a handful of Type 2 AGN showing evidence for variability. The work done so far confirms that there are type and wavelength dependence of intra-night optical variability of AGN.

• Journal of Family Resource Management and Policy Review
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• v.13 no.4
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• pp.17-38
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• 2009

Preferences on living arrangement and residence of the elderly depend on various changing factors as they get old. Among those factors, predictable and crucial factors are the condition of their health and spouse. Thus, this study is focused on living arrangement and the residential preference of the elderly according to their health and existence of a spouse. A sample of 500 elderly aged over 65 is analyzed by $x^2$ test, and multiple logistic regression. The results could be summarized as follows; First, 45.2% of the elderly who participated in this survey prefer 'living apart from their children but living close by'. And 19.8% of the elderly want to 'live with their children'. Second, the elderly with a spouse and the elderly who live apart from their children tend to prefer living independently. Third, the elderly with good health living in single-family houses and the elderly with high self-esteem tend to prefer the residential facilities for the elderly. Fourth, the elderly with health problems who have generous allowances and live in a city tend to prefer the residential facilities for the elderly. Fifth, factors such as gender, age, condition of health, allowances, living regions, type of house, self-esteem influence residential preferences of the elderly without a spouse. Older men with more allowances, in good health, living in row house and apartment, in a mid-size city tend to prefer living in the residential facilities for the elderly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8A
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• pp.610-617
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• 2009

This paper proposes a cross-layer design combining adaptive modulation and coding (AMC) with truncated hybrid automatic repeat request (HARQ) for wireless multicast transmission, in order to increase the spectral efficiency while meeting the target quality-of-service (QoS). In the design, we provide the selection criterion of AMC so as to satisfy the target packet error rate (PER) of all users when the multicast data is received through the common channel and the number of retransmission is limited by the delay constraint of the service. The analytically derived results show that the cross-layer design using HARQ provides a better spectral efficiency than the AMC without HARQ by allowing retransmission and code combining. It is also observed that the design for multicast outperforms that for unicast in the mid to high signal-to-noise ratio region.