• Environmental and Resource Economics Review
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• v.21 no.1
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• pp.3-25
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• 2012

Generally speaking, firms, faced with a regulatory environment, are likely to use more or less inputs than optimal level due to allocative inefficiency of inputs. This paper, first, tests allocative efficiency of fuel inputs and calculates the divergence between the actual and optimal levels of each fuel input conditional on the optimal level of capital stock in Korean thermal power industry. Then, given that each fuel is efficiently allocated. potential reduction of $CO_2$ is estimated over the period 1987~2008. The null hypothesis of allocative efficiency with respect to all fuels is rejected, indicating that thermal power plants fail to attain cost minimization subject do market prices. Allocative efficiency between each pair of fuels is also tested; efficient uses of fuels relative to each other are all rejected. Empirical results indicate that coal and gas are used more and oil is used less than optimal level. On average, more than 10 million tons of $CO_2$ per year could be reduced by achieving allocative efficiency of fuels.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.102-103
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• 2002

옥시테트라싸이클린(OTC)은 테트라사이클린계 항균물질로 비브리오병, 지느러미 붉음병, 인린 병, 아가미 썩음병 등과 같은 수산동물 질병 치료에 많이 사용되고 있는 항균제이다. 어류의 질병을 치료하기 위해 투여된 항생제에 대하여 어체내의 잔류농도에 대한 과학적 규명없이 관습적이고 반복적으로 사용되고 있어 과잉투여에 의한 경제적 손실, 과소투여에 의한 내성균의 발현, 양식 어류 체내의 항생물질 잔류 농도등 항생제 사용 문제는 양식산업뿐 아니라 수산가공 입장에서도 매우 중요한 현안으로 대두되고 있다. (중략)

• 농업기술회보
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• v.48 no.3
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• pp.21-22
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• 2011

1980년대 후반부터 정부의 규제가 약해진 틈을 타 화학농약 사용이 일반화되면서 인삼수량은 획기적으로 늘었으나 농약남용의 문제가 발생했다. 또한 단기간에 인삼뿌리를 굵게 키우기 위해 앙분이 과잉 축적된 가축분 퇴비를 과용하게 되었고, 초작지 부족으로 연작지가 늘어남에 따라 뿌리썩음병과 같은 병해도 증가하여 수량과 품질이 떨어지는 결과를 초래했다.

• 농업기술회보
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• v.48 no.4
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• pp.42-42
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• 2011

감귤재배 시 반드시 필요로 하는 양분 중의 하나인 붕소는 잎에서 광합성 작용으로 만들어진 당분을 과실, 뿌리 및 줄기 등으로 이동하도록 돕는다. 하지만 적은 양으로 민감하게 피해현상이 발생하므로 일반 온주밀감재배에는 붕소를 별도로 거의 시용하지 않았다. 그러나 최근 신품종이 보급되면서 특이 품종에서 붕소의 결핍증상이 쉽게 나타나고 있어 이에 대한 사례와 결핍 시 방지대책과 과잉으로 사용 시 나타나는 피해증상을 조사했다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.173-174
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• 2009

증착 온도를 변화시켜 성장시킨 Ga-doped ZnO 박막을 수소 열처리를 통해 구조적 전기적 광학적 성질을 기존의 투명 전극으로 사용되는 ITO (indium tin oxide) 물질을 대체할 수 있는 가능성을 확인하였다. 열처리 전 Ga-doped ZnO 박막의 증착온도가 증가함에 따라 전기적 성질이 향상되었지만 423 K 이상의 온도에서는 과잉 dopant인 Ga 으로 인한 기여도가 커져 $ZnGa_{2}O_{4}$와 $Ga_{2}O_{3}$ 상으로 인해 박막의 질이 저하되는 것을 확인할 수 있었다. 수소 열처리 후 과잉 dopant Ga 으로 인하여 상온에서 올린 박막만 전기적 성질이 향상되었지만 나머지 증착 온도 변화를 둔 박막에서는 큰 변화가 없었다.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.663-670
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• 2009

Performing random number simulations, we obtained an approximate distribution of the number of ways arranging molecules in a binary lattice solution of nonrandom mixing with a specific interaction. From the distribution an approximate equation of excess Gibbs energy for a binary lattice solution was derived. Using the equation, liquid-vapor equilibrium at constant pressure for 15 binary solutions were calculated and compared with the result from Wilson equation, Van Laar equation and Redlich-Kister equation.

• Annual Conference of KIPS
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• 2001.10a
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• pp.581-584
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• 2001

신경망이 만들어내는 출력에 대한 정보는 수치적으로 분산되어 신경망에 저장되므로, 인간이 직접 해석하기가 힘들다. 본 논문에서는 LRE(link rule extraction)기법인 NofM 알고리즘의 6단계 중에서 초기 단계인 가중치 군집화 단계를 개선하여 추출되는 규칙들의 전제부에 들어가는 규칙 조건들의 수를 조절함으로써, 추출된 규칙이 입력 특성에 대한 정보를 과잉 일반화하거나, 과잉 구체화하는 것을 피할 수 있음을 실험을 통해 보였다. 일반적으로 NofM 알고리즘에서 가중치들을 군집화한 때는 Join 알고리즘을 사용하는데, 본 논문에서는 Join 알고리즘의 Join condition을 0.05부터 0.25까지 0.05씩 점진적으로 확대하여 클러스터링을 하여줌으로써 신경망의 출력에 중요한 역할을 하는 가중치들을 효과적으로 군집화함을 보였다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.16 no.2
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• pp.279-285
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• 2005

Objectives : This study was performed to evaluate the efficacy and safety of MPH-OROS and parental satisfaction for treatment of children with ADHD Method : The 569 participants were clinically diagnosed for ADHD using DSM-IV criteria. We switched current medication to MPH-OROS or introduced MPH-OROS for treatment of ADHD. We assessed the clinical global impression severity of illness (CGI-S), the clinical global impression severity of improvement(CGI-I). And the parents of participants measured the Korean version of Conners rating scale at baseline, the 1 st week and the 3rd week after MPH-OROS trial. At the 3rd week, the parents measured the parent satisfaction questionnaire. Results : $13\%$ of participants dropped out because of several causes including side effects. The change of CGI-S was significantly decreased. Using CGI-I, the improvement was $72.3\%$ at the 1st week and $87.4\%$ at the 3rd week. The total score of the Korean version of Conners parent rating scale was significantly decreased. The participants complaining one or more of side effects were 119$(20.7\%)$, and the most common side effect was anorexia. The $94\%$ of parents replied that they were overall satisfied with MPH-OROS trial. Also the advantages of MPH-OROS of parental report were the long duration of the drug, the improvement of schoolwork and attitude, the improvement of home behavior and homework and the improvement of overactivity. Conclusion : MPH-OROS is effective and well-tolerated in actual clinical use for ADHD.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.637-640
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• 2005

The density of polar-nonpolar liquid mixtures composed of methyl tert-butyl ether(MTBE) and 2,2,4-trimethylpentane, and methyl ethyl ketone (MEK) and 2,2,4-trimethylpentane, and the density of polar-polar liquid mixture of MTBE and MEK were measured by densitometer at 278.15 K, 288.15 K and 298.15 K, respectively. The excess molar volume of the binary systems calculated from the measured density was shown good agreement with the calculated one by the cubic Peng-Robinson- Stryjek-Vera (PRSV) equation of state together with Huron-Vidal mixing rule and it confirmed that the cubic PRSV equation of state could be used in the molar volume calculation of polar mixture.

• Geotechnical Engineering
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• v.2 no.1
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• pp.15-26
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• 1986

Consolidated undrained standard triaxial tests for two remoulded clays and one undisturbed clay were carried out in order to find out the relationship between excess pore water pressure and axial strain in mortally consolidatated saturated clays during undrained shear. Tests were performed with isotropically-normally consolidated specimens by strain controlled and stress controlled loading. As the result of this stud!'a hyperbolic function expressing the relationship between pore water pressure and strain was found out, and it showed the same form as the Kondner's hyperbolic function for stress·strain behaviour. Two parameters used for the function can be obtained by CU-triaxial test.