• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2969-2972
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• 2009

A mild and efficient method has been developed for condensation of substituted phenol with ${\beta}$-ketoester in the presence of catalytic amount of ammonium metavanadate (10 mol%) at ambient temperature to afford the corresponding substituted 4-methyl-2H-chromen-2-one in high yields under mild conditions. Utilization of commercially available inexpensive catalyst makes this manipulation very interesting from an economic perspective.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2883-2886
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• 2009

A simple, highly efficient and environmentally benign method for the synthesis of 3-styrylchromones from 3-formylchromones and 4-nitrophenylacetic acid/4-nitrotolune in the presence of catalytic amount of basic ionic liquid 1-butyl-3-methylimidazolium hydroxide [(bmim)OH] carried out under the influence of microwave irradiation. This method gives remarkable advantages such as, short reaction times, simple work-up procedure and moderate to good yields. The ionic liquid was successfully reused for four cycles without significant loss of activity.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2887-2889
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• 2009

An efficient and easy method for one-pot three-component synthesis of amidoalkyl naphthols by the condensation of aromatic/heteroaromatic/aliphatic aldehydes, 2-naphthol and amides or urea under thermal condition at $60^{\circ}C$ in the presence of acidic ionic liquid 1-butyl-3-methylimidazolium hydrogen sulphate ([bmim]$HSO_4$) has been described.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1856-1860
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• 2012

$SnO_2/SiO_2$ nanocomposite has been synthesized by using sol-gel method. Prepared catalytic materials has been well characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmer-Teller (BET) surface area, and temperature-programmed desorption of ammonia ($NH_3$-TPD). $SnO_2/SiO_2$ nanocomposite catalyzed synthesis of 2-arylbenzothiazoles by the cyclocondensation of 2-aminothiophenol and aromatic aldehydes under reflux condition in 1:1 EtOH:$H_2O$. After completion of the reaction, catalyst can be recovered efficiently and reused with consistent activity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.1
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• pp.23-26
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• 2017

Social Welfare is useful concept for evaluating the effectiveness of an economic policy in micro economics. This paper focuses on Social Welfare(SW) of electricity market incorporating demand response(DR). Competition between DR and generation company is modeled as a simple bid function. DR function can be considered as an negative generation(called Negawatt) and as an element of modified demand function. These two approaches result in the same demand reduction, generation power, and the market price. However, SW in the modified demand function approach is not identical to SW in the Negawatt approach. It makes the numerical index of DR effectiveness less persuasive. This paper proposes modified definition of SW in the demand function approach. The proposed definition of SW leads the DR effectiveness index to be identical to that in the Negawatt approach.

• Language and Information
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• v.6 no.2
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• pp.83-104
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• 2002

I argue that Definiteness Effect (DE) should include Indefiniteness Restriction (IR) as well as Definiteness Restriction (DR). DR is exhibited by existential constructions, predicate nominals, inalienable possession constructions, and verbs with semantic features like 〔((CAUSE TO) COME TO) EXIST〕. IR is caused by some existence presupposition of aspectual adverbs, aspectual verbs, repetitives, and topic markers. The environments for DR and IR determine the (in)definiteness of Korean bare noun phrases which otherwise can be used either way. The neutralization of DR is also induced by focus which imposes a certain amount of structure on the event quantification. Van der Sandt's (1992) Presuppositions-as- Anaphora-Theory is effectively used to account for those examples from DR, ID, and the neutralization of BR.

• Journal of Chest Surgery
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• v.54 no.3
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• pp.232-234
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• 2021

Ependymomas arise from ependymal cells and can grow at any site in the central nervous system (CNS), as well as in some locations outside of the CNS. The latter is rare, contributing to the frequent misdiagnoses of such cases. Herein, we present the case of a 54-year-old man with a history of lower limb weakness and numbness. Magnetic resonance imaging revealed an extradural, heterogeneously enhanced solid lesion with a regular and well-defined border in the posterior mediastinum. A post-resection histopathological examination revealed tumor-forming perivascular pseudo-rosettes that showed immunoreactivity against glial fibrillary acidic protein, epithelial membrane antigen, and vimentin, as well as a high Ki-67 labeling index. Based on pathological features, a diagnosis of anaplastic ependymoma was established.

• Journal of Acupuncture Research
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• v.25 no.3
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• pp.71-86
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• 2008

Objectives & Methods : The purpose of this study is to observe the effects of Drynariae Rhizoma Herbal-acupuncture infusion solution at Umgok($KI_{10}$) on Osteoporotic Rats Induced by Ovariectomy. The author performed several experimental items to analyze cytotoxic, osteoporosis evaluation, change of ALP, osteocalcin, Ca and histological change of tibia. Results : 1. BMD were increased meaningly in DR-HA than control group. 2. ALP was not inhibited by DR-HA, osteocalcin was decreased meaningly in DR-HA. 3. Osteoclast like cell in tibia was increased meaningly in control group, decreased meaningly in DR-HA. 4. In the histological study in tibia, TBV and TBT were significantly increased, GPL was significantly decreased in the DR-HA than control group. Conclusions : From the result above, the results suggest that DR-HA at $KI_{10}$ has significant effect on osteoporosis, and to be put to practical use in the future osteoporosis clinic.

• The Journal of Korean Medicine
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• v.25 no.4
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• pp.26-35
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• 2004

Drynariae Rhizoma (DR), an herbal medicine known to clean blood and improve its circulation, frequently appears as the main ingredient in the prescriptions for bone injuries. Currently, it is unclear how contributes pharmacologically to the reformation of bone. Therefore, we have done this study. Systematic administrations of TGFβ1 and water extract of DR diminished the polyarthritis development in rats. TGFβ administration (0.1-2 ㎍/animal) and DR (10-100 ㎍/animal), initiated 1 day before an arthritogenic dose of streptococcal cell wall fragments, virtually eliminated the joint swelling and distortion observed during the acute phase and the chronic phase of the disease. The TGFβ and DR synergistically suppressed the arthritis when the administration was begun after the acute phase of arthritis. Also, the synergistic activity between TGFβ and DR was confirmed in their suppression of arthritis in rats. Consistent with the inhibition of inflammatory cell recruitment into the synovium, TGFβ1 and DR reversed the leukocytosis associated with the chronic phase of the arthritis.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.399-402
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• 2005

For efficient and accurate diagnosis of ultrasound images, the time gain compensation (TGC) and dynamic range (DR) control of the ultrasound echo signal are important. TGC is for compensating the attenuation of the ultrasound echo signal along the depth, and DR is used to control the image contrast. In this paper, we propose an algorithm for finding the optimized values of TGC and DR automatically. For TGC, the degree of compensation is determined along the depth based on the effective attenuation estimation of ultrasound signal. For DR optimization, we introduce a novel cost function on the basis of the characteristics of ultrasound image, which provides the minimum value at the optimal DR. Experiments have been performed by applying the proposed algorithm to a real US imaging system. The results show that the algorithm automatically can determine the values of TGC and DR in realtime so that the subjective quality of the corresponding US image may be good enough for diagnosis.