• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제15권5호
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• pp.390-394
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• 2009

시맨틱 웹 기반의 소셜 네트워크는 다양한 분야에서 높은 활용성을 가진다. 본 논문에서는 FOAF 기반 소셜 네트워크에 대하여 다양한 분석을 수행하고, 이를 바탕으로 네트워크 내의 전문가를 추천하는 시스템을 제안한다. 분석 시스템은 SparQL, RDFS 추론, 그리고 시각화 도구를 이용하여 온톨로지 기반 소셜 네트워크에 대한 효과적인 활용 방안을 제시한다. 그리고 이러한 분석 시스템을 실제 소셜 네트워크에 적용시켜 Centrality, Small world, Scale free 특성 등의 다양한 분석을 수행하고, 특정 분야에 대한 전문가를 분석하는 방법을 제시한다. 이러한 활용방법은 마케팅, 조직 관리, 지식 경영 시스템 등 다양한 분야에서 이용될 것으로 기대한다.

• 대한기계학회논문집B
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• 제27권5호
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• pp.635-643
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• 2003

Parametric study for the analysis of performance characteristics of a planar -type solid oxide fuel cell(SOFC) using computational flow analysis is conducted. A planar -type SOFC, which is composed by two gas channels (fuel and ai.) and one set of anode-electrolyte-cathode assembly, is modeled as a two -dimensional isothermal case. Results of computational analysis of flow field including distributions of mass fractions in gas channels are used to the performance analysis of the fuel cell. Flow analysis makes it possible to consider current density distributions along the length of the cell in the process of performance analysis of the SOFC. As results of parametric study, it is found that the mole fraction of fuel at the inlet of fuel channel, operating pressure and temperature are closely related to the performance characteristics of SOFC.

• Parasites, Hosts and Diseases
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• 제39권4호
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• pp.329-332
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• 2001

More than 1,500 clams of Corbicula fluminea, the most favorable food source of freshwater bivalves in Korea, were collected from 5 localities to examine cercarial and metacercarial infection with Echinostoma cinetorchis. Although 3 clams infected with suspicious E. cinetorchis metacercariae out of 200 specimens collected at Kangjin, Chollanam-do were detected, no cercarial and metacercarial infections with E. cinetorchis were observed in field-collected Corbicula specimens. In the susceptibility experiments with laboratory-reared clams, those infected with miracidia of E. cinetorchis did not release their cercariae up to 60 days after infection. To confirm the identity of second intermediate host of E. cinetorchis experimentally, a total of 30 clams were exposed to the cercariae from Segmentina hemisphaerula that had been infected with miracidia of E. cinetorchis. The clams were susceptible to cercariae of E. cinetorchis with an infection rate of 93.3%. Metacercariae from clams taken more than 7 days after cercarial exposure were fed to rats (S/D strain), and adult worms of E. cinetorchis, characterized by 37-38 collar spines on the head crown, were recovered from the ileocecal regions. This is the first report of C. fluminea as a possible second intermediate host of E. cinetorchis.

• 대한기계학회논문집A
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• 제39권6호
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• pp.589-596
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• 2015

횡등방성 압전재료에 대한 모서리경사균열 문제를 해석하였다. 두 기계적 집중 면외하중과 전기적 집중 면내하중이 표면과 균열면에 각각 작용하고, 균열면은 절연균열면이다. 일반화된 변위벡터를 도입하고 Mellin 변환을 사용하여 문제를 수식화하고, 이로부터 Wiener-Hopf 식을 유도하였다. 이식을 풀므로써 폐형으로 주어지는 해를 얻었다. 임의의 균열길이나 경사각에 대해서도 적용이 되는 응력 및 전기변위 강도계수와 에너지 방출율을 구하였다. 이 해는 중첩에 의하여 임의로 분포하는 전기기계하중 문제에 대한 해를 제공하는 기본해로 사용될 수 있다.

• Bulletin of the Korean Chemical Society
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• 제24권3호
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• pp.274-278
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• 2003

New banana-shaped achiral compounds, 1,3-phenylene bis [4-{4-(alkenyloxy) phenyliminomethyl}benzoate]s were synthesized by varying the length of alkenyl group; their ferroelectric properties are described. The smectic mesophases, including a switchable chiral smectic C $(Sm\;C^*)$ phase, were characterized by differential scanning calorimetry, polarizing optical microscopy and triangular wave method. The presence of vinyl groups at the terminals of linear side wings in the banana-shaped achiral molecules containing Schiff's base mesogen induced a decrease in melting temperature and formation of the switchable $(Sm\;C^*)$ phase in the melt. The smectic phases having the octenyloxy group such as $(CH_2)_6CH=CH_2$ showed ferroelctric switching, and their values of spontaneous polarization on reversal of an applied electric field were 120 nC/cm² (X=H) and 225 nC/ cm² (X=F), respectively. We could obtain ferroelectric phases by controlling the number of carbon atom in alkenyloxy chain of a bent-core molecule.

• 한국안전학회지
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• 제20권4호
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• pp.1-8
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• 2005

Effects of Nb(Niobium) contents and solution annealing on the strength and fatigue life of 18%Ni maraging steel commonly using in aircraft, space field, nuclear energy, and vehicle etc. were investigated. Also the fatigue life stress intensity factor were compared experiment result and FEA(finite element analysis) result. The more Nb content, the higher or the lower fatigue life on base metal specimens or solution annealed specimens showing that the fatigue lift was almost the same. The maximum stresses of X, Y, and Z axis direction showed about $2.12{\times}10^2MPa,\;4.40{\times}10^2MPa\;and\;1.32{\times}10^2MPa$ respectively. The Y direction stress showed the highest because of the same direction as the loading direction. The fatigue lives showed about 7% lower FEA result than experiment result showing almost invariable error every analyzed cycle. Stress intensity factor of the FEA result was lower about $3.5{\sim}10%$ than that of the experiment result showing that the longer fatigue crack length the higher error. It considered that the cause for the difference was the modeled crack tip having always the same shape and condition regardless of the crack growth.

• The Korean Journal of Physiology and Pharmacology
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• 제23권6호
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• pp.467-474
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• 2019

Exposure to lead during pregnancy is a risk factor for the development of psychiatric disorders in the offspring. In this study, we investigated whether exposure to low levels of lead acetate (0.2%) in drinking water during pregnancy and lactation causes behavioral impairment and affects the expression of proteins associated with neurodevelopment. Lead exposure altered several parameters in rat offspring compared with those unexposed in open-field, social interaction, and pre-pulse inhibition tests. These parameters were restored to normal levels after clozapine treatment. Western blot and immunohistochemical analyses of the hippocampus revealed that several neurodevelopmental proteins were downregulated in lead-exposed rats. The expression was normalized after clozapine treatment (5 mg/kg/day, postnatal day 35-56). These findings demonstrate that downregulation of several proteins in lead-exposed rats affected subsequent behavioral changes. Our results suggest that lead exposure in early life may induce psychiatric disorders and treatment with antipsychotics such as clozapine may reduce their incidence.

• 대한후두음성언어의학회지
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• 제33권3호
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• pp.142-155
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• 2022

Diagnosis using voice is non-invasive and can be implemented through various voice recording devices; therefore, it can be used as a screening or diagnostic assistant tool for laryngeal voice disease to help clinicians. The development of artificial intelligence algorithms, such as machine learning, led by the latest deep learning technology, began with a binary classification that distinguishes normal and pathological voices; consequently, it has contributed in improving the accuracy of multi-classification to classify various types of pathological voices. However, no conclusions that can be applied in the clinical field have yet been achieved. Most studies on pathological speech classification using speech have used the continuous short vowel /ah/, which is relatively easier than using continuous or running speech. However, continuous speech has the potential to derive more accurate results as additional information can be obtained from the change in the voice signal over time. In this review, explanations of terms related to artificial intelligence research, and the latest trends in machine learning and deep learning algorithms are reviewed; furthermore, the latest research results and limitations are introduced to provide future directions for researchers.

• 자원ㆍ환경경제연구
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• 제12권4호
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• pp.611-635
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• 2003

본 연구는 R&DDD(Research & Development, Demonstration, Dissemination: $R&D^3$)로 구성되는 연구개발과정의 마지막 단계인 확산단계에 관한 내용을 다루고 있다. 확산단계(Dissemination Stage)에서는 개발된 기술과 다른 대안들과의 비교 평가가 이루어지고 최종적으로 가장 바람직한 방안이 선정되게 된다. 이 단계에서 이루어지는 기술대안에 대한 평가는 단순한 과정이 아니고, 기술적 특성뿐만 아니라 경제적 효과 등 여러 가지 요소들이 고려되어야 하는 복합적인 평가과정을 거치게 된다. 이는 오늘날 산업계 각 분야에서 바람직한 기술대안의 평가, 선정, 적용이 기업의 경쟁우위에 지대한 영향을 미치며 나아가 기업의 생존 및 성장을 좌우하기 때문이다. 본 연구에서는 열공급시스템의 기술적 대안에 대한 AHP방법을 고찰하고, 이 방법의 실무적 적용가능성을 검토하기 위해 에너지기술분야에서 폐열 활용시스템 대안들에 대한 평가에 적용한 결과를 보여주고 있다.

• 한국환경농학회지
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• 제15권4호
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• pp.488-493
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• 1996

화본과 잡초를 방제하기 위하여 사용되고 있는 제초제 quizalofop-ethyl의 토양중에서 잔류소장과 토양미생물상에 미치는 영향을 구명하기 위하여 전남농촌진흥원 시험포장 토양인 연곡식양토와 제주도 화산회 토양인 남원통에서 시험을 수행한 결과 토양중에서 제초제 quizalofop-ethyl의 반감기는 연곡통 15일, 남원통 16일이었으며, Baocteria, Actinomycetes, fungi, Pseudomonas는 quizalofop-ethyl에 의해 영향을 받아, 그 수가 현저하게 감소되었으나 Fusarium의 수는 큰 변화가 없었으며, 액체 배양에서 Fusarim을 접종한 배지에서는 quizalofop-ethyl의 량이 감소가 없는 것으로 보아 토양중에서 quizalofop-ethyl의 분해는 Fusarium에 의한 것으로 여겨졌다.