• Annual Conference on Human and Language Technology
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• 2009.10a
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• pp.197-201
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• 2009

이 논문은 영어 문장에서 대명사의 참조해소 시스템을 구현한다. 대명사는 문장에서 반복되는 말 대신에 사용하는 단어이다. 반복되는 말을 선행어라고 하며 대명사는 선행어보다 간결한 형식으로 사용된다. 정보검색이나 정보추출에서 대명사를 그대로 색인하여 검색하면 정확한 정보를 추출할 수 없다. 따라서 대용어가 가리키는 개체를 정확히 파악해서 이 정보를 색인하고 검색하면 정보검색, 정보추출, 질의응답의 성능을 크게 개선할 수 있다. 이 논문에서는 CRF모델을 이용해서 이용하여 영어 문서에서 대명사 참조해결 방법을 제안하고 이를 구현한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.04a
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• pp.787-790
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• 2015

본 연구에서는 글의 구성요소를 추측하는 가장 높은 성능을 나타내는 알고리즘을 제시한다. 실험 방법은 글의 각 문장에 대한 자질을 추출, 자질 선택, 그리고 데이터에 대해 여러 기계학습 알고리즘을 학습시킨 후 성능을 비교하여 진행하였다. 또한 이 중 가장 높은 성능을 보이는 CRF를 기존에 연구되어 있는 성능과도 비교하였다. 마지막으로 CRF가 구성요소를 추측하는 데 있어서 가장 높은 성능을 보이는 이유에 대해 분석하였다. 국내의 유명 어학원 및 토플 웹사이트를 통해 1969개의 토플 에세이를 수집했으며 2명의 전문 평가자를 통해 각 문장을 8개의 분류로 나누었다. 이를 CRF를 적용한 결과 87.2%의 F score가 나왔으며 기존 연구결과, 그리고 다른 알고리즘보다 높은 성능을 보였다.

• Annual Conference on Human and Language Technology
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• 2020.10a
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• pp.108-111
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• 2020

한국어 의존 파싱은 전이 기반 방식과 그래프 기반 방식의 두 갈래로 연구되어 왔으며 현재 가장 높은 성능을 보이고 있는 그래프 기반 파서인 Biaffine 어텐션 모델은 입력 시퀀스를 다층의 LSTM을 통해 인코딩 한 후 각각 별도의 MLP를 적용하여 의존소와 지배소에 대한 표상을 얻고 이를 Biaffine 어텐션을 통해 모든 의존소에 대한 지배소의 점수를 얻는 모델이다. 위의 Biaffine 어텐션 모델은 별도의 High-Order 정보를 활용하지 않는 first-order 파싱 모델이며 학습과정에서 어떠한 트리 관련 손실을 얻지 않는다. 본 연구에서는 같은 부모를 공유하는 형제 노드에 대한 점수를 모델링하고 정답 트리에 대한 조건부 확률을 모델링 하는 Second-Order TreeCRF 모델을 한국어 의존 파싱에 적용하여 실험 결과를 보인다.

• Journal of Sasang Constitutional Medicine
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• v.25 no.4
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• pp.359-372
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• 2013

Objectives The object of this study was to observe the effects of Hyeongbangjihwhang-tang (HB; Soyangin prescription) on the 5/6 NTX induced CRF rats. Methods Each of Hyeongbangjihwhang-tang aqueous extracts 200mg/kg were orally administered once a day for 35 days from 4 weeks after 5/6 NTX surgery. Four groups, each of 8 rats per group were used in this study, were sham group, CRF group, ${\alpha}$-Tocoperol group and HB group. Changes on the left remnant kidney weights, serum BUN, creatinine levels, caspase-3, PARP immunoreactivities were observed to nephroprotective effects, and relative immunomodulatory effects were monitored based on the changes of lymphatic organ weights and splenic cytokine contents. In addition, the changes on the kidney MDA, GSH contents and SOD, CAT activities were also calculated for antioxidant effects, and the effects on the CRF related cachexia were demonstrated based on the changes of body and epididymal fat pad weights, serum TG, TC, LDL and HDL levels. Results and Conclusions 1) HB was significantly decreased the left remnant kidney weights, serum BUN, creatinine levels and caspase-3, PARP immunoreactivities. 2) HB was significantly increased lymphatic organ weights and splenic cytokine contents. 3) HB was significantly increased body and epididymal fat pad weights, and was significantly decreased serum TG, TC, LDL and HDL levels. 4) HB was significantly decreased MDA contents, and was significantly increased GSH contents and SOD, CAT activities. The results obtained in this study suggest that HB significantly retarded immunosuppressions and cachexia related to the 5/6 NTX induced CRF through modulations of oxidative defense systems. Especially HB showed the highest favorable effects more than those of ${\alpha}$-tocoperol.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.29-37
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• 2009

Objectives: The goal of this study was to investigate the antidepressive effect of Bupleuri Radix (BR). Methods : The forced swimming test (FST) was performed. Also the expression of corticotropin releasing factor (CRF), c-Fos and tyrosine hydroxylase (TH) was measured immunohistochemically at paraventricular nucleus (PVN) and locus coeruleus (LC). Concentration of adrenocorticotrophic hormone (ACTH) was measured in plasma by ELISA method. Results : The immobility in BR400 Group was significantly decreased in comparison with the control group (p

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.3
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• pp.157-163
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• 2005

The increasing of greenhouse gases may change agricultural environment. The agronomic productivity will depend upon change of temperature, precipitation, solar radiation and fertilization. Particularly, nitrogen fertilization considerably influences rice productivity and agricultural environments. This experiment was conducted to study transformation of nitrogen and to determine the primary yield components responsible for yield differences in paddy soil. $NH_4-N$ concentration of NPK plot in surface water of paddy soil was $2.07mg\;L^{-1}$ at 5 days after transplanting, and then was decreased sharply due to rice absorption and loss to environment. $NO_3-N$ concentration of NPK plot in surface water was $3.97mg\;L^{-1}$ at 10 days after transplanting. $NO_3-N$ concentration range of CRF plot in surface water was $3-5mg\;L^{-1}$ at 30th after transplanting. The accumulation of $NH_3$ volatilization in NPK plot was $22.39kg\;ha^{-1}$, which accounted for 20% of N fertilizer applied but using of CRF fertilizer can reduce $NH_3$ volatilization by 67% in paddy soil. Use efficiency of N fertilizer was not different between CRF70% and CRF100% plot. Rate of N use efficiency were 27.4%, 51.2%, 49.0% in paddy field NPK, CRF70% and CRF100% plots respectively. The yield of CRF70% showed the best effect with 9.3% increase production ratio, compare with NPK plot.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.1
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• pp.81-92
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• 2001

Stress has been linked to the pathophysiology and pathogenesis of various psychiatric illnesses. Over the past few years, our understanding of the brain and neuroendocrine systems that are linked to stress responses has increased enormously. This article reviews a series of animal and human studies to understand what are the central pathways by which stress is perceived, processed, and transduced into a neuroendocrine response. We focus on the limbic-hypothalamic-pituitary-adrenal(LHPA) axis and several neurotransmitter systems such as norepinephrine, CRF, serotonin, acetylcholine, and dopamine. LHPA stress circuit is a complex system with multiple control mechanisms which are altered in pathological states. CRF and related peptides in the central nervous system appear to enhance behavioral responses to stressors. Norepinephrine systems are also activated by stressors and cause the release of catecholamines from the autonomic nervous system. CRF-norepinephrine interaction makes a feed-forward system which may be important for an organism to mobilize not only the pituitary system but also the central nervous system, in response to environmental challenges. The interactions among several neurotransmitters and endocrine systems appear to play key roles in mediating various behavioral and psychological stress responses involving abnormal responses to stressors such as anxiety and affective disorders.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.640-647
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• 2016

By minimizing fluorescence interference phenomena, aequorin-based luminescence technology can provide a relatively sensitive detection platform with integration of $G{\alpha}16$ protein in order to track internal calcium mobilization by G protein-coupled receptors (GPCR). In this type of cell-based functional assay format, it is essential to optimize the transfection process of a receptor and $G{\alpha}16$ protein. For this study, corticotropin releasing factor receptor subtype 2(CRF2) was set as a model system to generate three stable cells with CRF2 and $G{\alpha}16$ in addition to transiently transfected cells under three different conditions. Agonist (sauvagine) and antagonist (K41498) responses in those cells were analyzed to develop the optimum transfection process. As a result, the effective signal ratio in the dose response experiments of sauvagine and K41498 were at least 10-fold higher (z'=0.77) in CRF2-$G{\alpha}16$ stable cells. For the transient transfection cells, stable expression of $G{\alpha}16$ prior to the CRF2 represented a two-fold higher signal (z'=0.84) than the other cases of transient transfection. In conclusion, for the utilization of transient transfection processes to develop a cell-based GPCR functional assay system, it is suggested to introduce various target receptors after stable expression of $G{\alpha}16$ protein.

• Korean Journal of Biological Psychiatry
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• v.10 no.1
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• pp.62-69
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• 2003

Corticotropin-releasing factor(CRF) and neuropeptide Y(NPY) are known to play important roles in mediating stress responses and stress-related behavior. To elucidate the role of neuropeptides in response to the condition that had paired with traumatic event, we observed the changes of CRF and NPY by immunohistochemistry using a conditioned footshock paradigm. Male Sprague-Dawley rats were placed in a shuttle box and exposed to 20 pairings of a tone(< 70dB, 5sec) followed by a footshock(FS, 0.8mA, 1sec) over 60min. A second group was exposed to the tone-footshock pairings, returned to the homecage for 2days, and then reexposed to the test chamber and 20tones alone for 60min, prior to sacrifice. Control groups were : a) sacrificed without exposure to FS ; b) exposed to the tone-footshock pairings and then sacrificed two days later ; or c) exposed to the chamber and tones alone, returned to the homecage for 2days and then reexposed to the chamber and 20tones over 60min prior to sacrifice. CRF was increased in animals exposed to FS or the aversive condition(context and tone) that had paired to FS in bed nucleus of the stria terminalis (BNST) compared to the control. NPY was increased by FS in amygdala and PVN, but the condition previously associated with FS results in slight increase only in amygdala area. These results suggest that the BNST appears to be the mostly involved neural circuit in response to explicit cues previously paired with footshock. Moreover, this study raise the possibility that increased CRF peptide in the BNST in response to re-exposure to the aversive condition may underlie, in part, the experience of conditioned fear-related anxiety behavior.

• Annual Conference on Human and Language Technology
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• 2017.10a
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• pp.143-146
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• 2017

심층학습 모델 중 LSTM-CRF는 개체명 인식, 품사 태깅과 같은 sequence labeling에서 우수한 성능을 보이고 있다. 한국어 개체명 인식에 대해서도 LSTM-CRF 모델을 기본 골격으로 단어, 형태소, 자모음, 품사, 기구축 사전 정보 등 다양한 정보와 외부 자원을 활용하여 성능을 높이는 연구가 진행되고 있다. 그러나 이런 방법은 언어 자원과 성능이 좋은 자연어 처리 모듈(형태소 세그먼트, 품사 태거 등)이 없으면 사용할 수 없다. 본 논문에서는 LSTM-CRF와 최소한의 언어 자원을 사용하여 다국어에 대한 개체명 인식에 대한 성능을 평가한다. LSTM-CRF의 입력은 문자 기반의 n-gram 표상으로, 성능 평가에는 unigram 표상과 bigram 표상을 사용했다. 한국어, 일본어, 중국어에 대해 개체명 인식 성능 평가를 한 결과 한국어의 경우 bigram을 사용했을 때 78.54%의 성능을, 일본어와 중국어는 unigram을 사용했을 때 각 63.2%, 26.65%의 성능을 보였다.