• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.365-372
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• 1997

This study was executed to measure the shear bond strength of Panavia EX and Panavia 21 when the Ni-Cr-Be alloy castings were cemented to the enamel surfaces with these cements. The cast metal plates of Ni-Cr-Be alloy were sandblasted and cemented to acid etched enamel surface with Panavia EX or Panavia 21. Their shear bond strength were measured with Instron Universal Testing machine. Within the limits of this study, following conclusions were withdrawn. 1. The mean shear bond strength were 26.85.7MPa, in Panavia EX and 28.35.2MPa, in Panavia 21. 2. t-Test revealed no statistical significance between two groups(.05 level) 3. Macroscopically, bond failures were revealed compound fracture at metal and enamel interfaces, in cases of both cements, as the cement attached partly on both metal and enamel surface.

• Journal of the Korean Regional Science Association
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• v.14 no.2
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• pp.1-33
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• 1998

Whereas previous researches on land policy after unification dealt with principally the problem of land confiscation under the communist reign, this research tried to propose a scheme of long-term land reform which was based on case studies on ex-socialist societies' experiences during their transformation, analysis on North Korea's institution related to land ownership and use. To reform North Korea's land ownership and use by the principle of market economy, North Korean should accumulate their commencing asset necessary for private ownership of land and housing. Therefore much focus should be put on the accumulation of the commencing asset at the early state of unification. On the extension of that line, the government of the Unified Korea should try to solve the problem of land confiscation by the communist party and land privatization in the region of North Korea. For the purpose, gradual land reform is more desirable than rapid one according to the case studies on ex-socialist societies. The government should avoid policies than can result in serious fiscal burden. Active participation of local government is highly recommendable in land tax and development. On the direction of land policy, this research proposed a four step long-term scheme of land reformation in North Korea. However, later researches should put more Korea. However, later researches should put more emphasis to the unification of land institution of North and South Korea which this research couldn't deal with sufficiently.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.540-543
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• 2007

We have investigated the vegetation in the peninsula located in Ongjeong-Li Seomyeon in Youngweol-gun. Since this is a limestone area, boxtrees, Abelia mosanensis T. H. Chung ex Nakai, and Selaginella stauntoniana Spring were abundant, as these are types of vegetation characteristic of limestone areas. Pinus densiflora S. et Z. was the most dominant woody plant, but vegetational changes, such as the dominance of Quercus variabilis Blume, Quercus dentata Thunb, and Quercus mongolica Fischer, were observed in spots. In particular, the growth of nursery plants of pinus densiflora S. et Z. was not observed, and young trees like Quercus mongolica Fischer grow as low vegetation of Pinus densiflora S. et Z.. Thus, the ecological succession of Quercus mongolica Fischer is predicted. Outside the investigation area, as herbaceous plants, various vegetations were observed, including Selaginella stauntoniana Spring, Thalictrum coreanum H. Lev., Mukdenia rossii(Oliv.) Koidz., Platanthera freynii Kraenzl., Cephalanthera longibracteata Blume, Potentilla dickinsii Franch., Patrinia rupestris(Pall.) Juss., Swertia pseudochinensis H. Hara, Vicia venosa(Willd.) Maxim., Pyrola japonica Klenze ex Alef., Disporum smilacinum A. Gray, Artemisia stolonifera(Maxim.) Kom. for. Stolonifera, Smilax nipponica Miq., Adenophora triphylla var. japonica(Regel) H. Hara, Isodon inflexus(Thunb.) Kudo, Gentiana scabra Bunge for. Scabra, Polygonatum odoratum var. pluriflorum(Miq.) Ohwi, Dioscorea quinqueloba Thunb., Syneilesis palmata(Thunb.) Maxim., Asparagus schoberioides Kunth, Eupatorium japonicum Thunb. ex Murray, Galium kinuta Nakai & Hara, Saxifraga fortunei var. incisolobata, Lilium amabile Palib., Siberian iris, Dictamnus dasycarpus Turcz., Atractylodes ovata(Thunb.) DC., and Lysimachia clethroides Duby.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.33-45
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• 2008

Auditory fear memory is thought to be maintained by fear conditioning-induced potentiation of synaptic efficacy. The conditioning-induced potentiation has been shown to be maintained, at least in part, by enhanced expression of surface AMPA receptor (AMPAR) at excitatory synapses in the lateral amygdala (LA). Depotentiation, reversal of conditioning-induced potentiation, has been proposed as a cellular mechanism for fear extinction. However, a direct link between depotentiation and extinction has not yet been tested. To address this, we applied both ex vivo and in vivo approaches to rats in which fear memory had been consolidated. We found a novel form of ex vivo depotentiation; the depotentiation reversed conditioning-induced potentiation at thalamic input synapses onto the LA (T-LA synapses) ex vivo, and it could be induced only when both NMDA and metabotropic glutamate receptors were co-activated. Extinction returned the enhanced T-LA synaptic efficacy observed in conditioned rats to baseline and occluded the depotentiation. Consistently, extinction reversed conditioning-induced enhancement of surface expression of AMPAR subunits in LA synaptosomal preparations. A GluR2-derived peptide that blocks regulated AMPAR endocytosis inhibited depotentiation, and microinjection of a cell-permeable form of the peptide into the LA attenuated extinction. Our results are consistent with the use of depotentiation to weaken potentiated synaptic inputs onto the LA during extinction, and they provide strong evidence that AMPAR removal at excitatory synapses in the LA underlies extinction. The results described here are in line with previous findings. Neural activity in the LA has been shown to decrease after extinction in the rat and human. The NMDAR dependency of the depotentiation fits nicely with a large body of evidence that fear extinction depends upon amygdala NMDARs. Similarly, blockade of metabotropic glutamate recepotrs in the LA has recently been shown to attenuate fear extinction.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.373-380
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• 2013

A severe pink mold rot on matured asian pear (Pyrus serotina Rehder) fruit occurred in the organic farmers' orchard in Jinju, Korea in October, 2012. Decay of pear fruit appeared as a softened water-soaked symptom that was easily punctured by pressure. Later pink mycelium appeared on the surface of pear fruit and produced a mass of powdery pink conidia spores. Optimum temperature for mycelial growth of T. roseum was $25^{\circ}C$. Conidia showed hyaline, smooth, 2-celled, thick-walled with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $10{\sim}22(34){\times}6{\sim}10(12){\mu}m$ in size. Conidiophore was erect, colorless, unbranched type, and 4-5 ${\mu}m$ width. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.285-292
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• 1998

We introduce the notion of TL-p-subgroups that is an ex-tension of the notion of fuzzy p=subgroups and show that a torsion TL-subgroup of an Abelian group with T=${\bigwedge}$ can be written as the intersection of its minimal TL-p-subgroups.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.115-119
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• 1978

To improve the feed value of rice straw, Tongil type rice straw and Persicaria Thunbergii Gross var. coreana Gross ex Nakai were mixed in the ratios of 10 : 90 (T1), 20 : 80 (T2), 30 : 70 (T3) and 40 : 60 (T4) in fresh weight and ensiled for 6 weeks. The chemical composition of fresh materials and silage, the organic acid contents and pH in silage were determined. And the results obtained were summarized as follow: 1. The crude protein content in rice straw was 8.18% of DM basis and that in Persicaria Thunbergii was 14.47%. And the nitrogen-free extract content in rice straw was 44.66% and.. that in Persicaria Thunbergii was 51.13%. 2. The optimum moisture contents were appeared in T2 as 72.12% and T3 as 66.43%. Considerably high crude protein contents were determined from all of treatments. 3. The pH of silage was varied from pH 3.8 of T1 to pH 4.5 of T2. And Total organic acid contents were increased from T1 to T4, but the percentage of lactic acid contents to total acid contents were decreased. 4. It was concluded that good quality silage could be made from rice straw with Persicaria Thunbergii and the best ratios of rice straw: Persicaria Thunbergii were between 20 : 80 and 30 : 70 in fresh weight.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.156-157
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• 2017

최근 스마트 기기의 발달과 센서들의 보급으로 인해 이들을 이용한 IoT(Internet of Things, 사물인터넷)가 빠르게 발전하면서 센서를 활용한 서비스 특화 디바이스들이 출시되어 IoT 플랫폼 및 서비스 시장 규모가 급격히 확대되고 있다. 본 논문에서는 센서간의 원활한 연결을 위해 센서들을 통합하고 관리할 수 있으며, 다양한 서비스에 적용될 수 있는 일반 목적의 IoT 허브를 구현해보았다. 라즈베리 파이를 기반으로 한 IoT 허브는 다양한 센서들의 정보를 수집해 센서 데이터를 서버에 전송하는 역할을 하며, 센서 관리를 위한 기능도 포함되어 있다.

• Korean Journal of Plant Taxonomy
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• v.44 no.1
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• pp.9-12
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• 2014

Talipariti simile (Blume) Fryxell, Malvaceae is reported as new record from Vietnam. The plant can be differentiated from its allied species T. macrophyllum (Roxb. ex Hornem.) Fryxell in having glabrescent stems with purplish and smaller hairs, lanceolate-oblong and smaller stipules and ovoid capsules which are devoid of apicule or beaks. Taxonomic description, line drawing and color photographs have been provided to add to the species identification. Furthermore, comparison of the diagnostic characters between this species and the above mentioned related species is made.

• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.201-207
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• 2017

An electron-excited temperature ($T_{ex}$) is not determined by the Boltzmann plots only with the spectral data of $4p{\rightarrow}4s$ in an Ar-plasma jet operated with a low frequency of several tens of kHz and the low voltage of a few kV, while $T_{ex}$ can be obtained at least with the presence of a high energy-level transition ($5p{\rightarrow}4s$) in the high-voltage operation of 8 kV. The optical intensities of most spectra that are measured according to the voltage and the measuring position of the plasma column increase or decay exponentially at the same rate as that of the intensity variation; therefore, the excitation temperature is estimated by comparing the relative optical-intensity to that of a high voltage. In the low-voltage range of an Ar-jet operation, the electron-excitation temperature is estimated as being from 0.61 eV to 0.67 eV, and the corresponding radical density of the Ar-4p state is in the order of $10^{10}{\sim}10^{11}cm^{-3}$. The variation of the excitation temperature is almost linear in relation to the operation voltage and the position of the plasma plume, meaning that the variation rates of the electron-excitation temperature are 0.03 eV/kV for the voltage and 0.075 eV/cm along the plasma plume.