• 한국컴퓨터정보학회논문지
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• 제4권4호
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• pp.25-33
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• 1999

서로 다른 기하학적 모델링 시스템을 사용하는 곡선 및 곡면의 자료 교환에서, 주어진 허용 오차 내에서 시스템이 지원하는 차수로 근사하는 차수감소를 종종 필요로 한다 본 논문에서는 기하학적 표현이 서로 다른 시스템간의 곡선 및 곡면의 교환에서 $\'{e}$의 차수감소에 의한 근사 변환 문제를 다룬다. 여러 가지 n차 $\'{e}$ 곡선을 n-1차 $\'{e}$ 곡선으로 감소하는 차수감소 방법들을 구현하고 각 방법들의 근사 변환한 실험적인 결과를 제공한다.

• 한국세라믹학회지
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• 제37권6호
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• pp.559-563
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• 2000

To decompose carbon dioxide, magnetite was synthesized with 0.2M-FeSO4$.$7H2O and 0.5 M-NaOH by coprecipitation. The deoxidized magnetite was prepared from the magnetite by hydrogen reduction for 1, 1.5, 2 hr. The degree of hydrogen reduction and the decomposition rate of carbon dioxide were investigated with hydrogen reduction time. The crystal structure of the magnetite was identified spinel structute by the X-ray powder diffractions. After magnetite was reduced by hydrogen, magnetite reduced by hydrogen become new phae(${\alpha}$-Fe2O3, ${\alpha}$-Fe) and spinel type simultaneously. After decomposing of carbon dioxide at 350$^{\circ}C$, new phse(${\alpha}$-Fe2O3, ${\alpha}$-Fe) were removed and the spinel type only existed. The specific surface area of the synthesized magnetite was 46.69㎡/g. With the increase of the hydrogen reduction time, the grain size, the hydrogen reduction degree and the decomposition rate of carbon dioxide was increased.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제9권2호
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• pp.99-106
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• 2005

We present a relation between the orthogonality of the constrained Legendre polynomials over the triangular domain and the BB ($B{\acute{e}zier}\;-Bernstein$) coefficients of the polynomials using the equivalence of orthogonal complements. Using it we also show that the best constrained degree reduction of polynomials in BB form equals the best approximation of weighted Euclidean norm of coefficients of given polynomial in BB form from the coefficients of polynomials of lower degree in BB form.

• Korean Journal of Mathematics
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• 제17권2호
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• pp.219-231
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• 2009

We show the existence of at least four solutions for the perturbed parabolic equation with Dirichlet boundary condition and periodic condition when the nonlinear part cross two eigenvalues of the eigenvalue problem of the Laplace operator with boundary condition. We obtain this result by using the Leray-Schauder degree theory, the finite dimensional reduction method and the geometry of the mapping. The main point is that we restrict ourselves to the real Hilbert space instead of the complex space.

• East Asian Economic Review
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• 제24권3호
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• pp.237-252
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• 2020

This paper characterizes the optimal reciprocal trade policy in the environment of Melitz (2003) with firm productivity heterogeneity. In particular, without making parametric assumptions on firm productivity distribution, this paper derives the optimal degree of reciprocal tariff reductions that maximize the world welfare. A reciprocal import subsidy raises the industry productivity, lowering aggregate price; a reciprocal import tariff helps correct the markup distortion, increasing nominal income. With all the conflicting effects of import tariffs on welfare considered, the optimal degree of reciprocity in multilateral tariff reduction is shown to be free trade.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.160-165
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• 2008

The concern in energy reduction in the field of architecture which takes up a big weight in domestic energy consumption is gradually increasing. For this reason, a lot of research work on this matter is being carried out. Particularly, it is generally required that currently used system in a structure for energy reduction should be maximized in its efficiency. In addition, research on several energy reduction typed systems is underway. Such a research work should not only include the one in time of the present but also keep up with the trend for future-oriented research. This research paper forecasted and analyzed the trend for global warming and demand of a structure for energy in the future by applying climate scenarios to cooling degree-day and heating degree-day. Also, this research found out the decrease in heating degree-days and increase in cooling degree-days until this moment due to the progress of global warming. In addition, as for heating degree-days in the future forecasted on the basis of HadCM3, it is estimated that the range of decrease could be ever bigger starting 2040 in case of Seoul and also starting 2010 in case of Ulsan ever after respectively. In case of cooling degree-days, it is estimated that its increase range could be bigger abruptly starting 2050, and after 2080, its increase range would be much bigger.

• 한국결정성장학회지
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• 제13권3호
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• pp.117-121
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• 2003

염화 니켈과 마그네슘 스테아린산 혼합 분말로부터 수소환원 공정에 의하여 니켈 분말을 제조하고 반응온도 및 마그네슘스테아린산의 첨가에 따른 분말의 특성을 검토하였다. 마그네슘 스테아린산을 함유한 경우 과도한 입자 성장의 억제로 인하여 입경 감소 효과가 있었다. 마그네슘 스테아린산의 함유량이 증가함에 따라 이에 따른 액상량의 증가로 인하여 입경 감소와 입자들간의 응집 정도에도 영향을 주었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권6호
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• pp.392-396
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• 2003

Purpose : The purpose of this study was to find the predictors for successful arthrocentesis for anterior disc displacement without reduction(ADD without Reduction) of the temporomandibular joint (TMJ). Patients and Methods : Arthrocentesis and lavage was carried out in 25TMJs of 22patients whose MRI findings were all anterior disc displacement without reduction. The effectiveness of the treatment was evaluated in terms of the postoperative range of maximal mouth opening (MMO) and the degree of postoperative pain score. Predectors which was analyzed were age, duration of painful locking, MMO, the degree of pain, perioperative clicking and the amounts of irrigation fluid. Results: 18cases (72%) was included to criteria for success. There were no significant differences in age, duration of locking, MMO and the degree of pain statistically. But In 15cases(83%) of successful cases, amouts of irrigated solution recovered to normal MMO were less than 150ml. And In 8cases (44%) of successful cases, perioperative clicking was appeared. Conclusion : Amounts of irrigated solution recovered to normal MMO and the appeareance of perioperative clkicking may be predictors of the successful results of arthrocenetesis of ADD without reduction of TMJ.

• 대한디지털의료영상학회논문지
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• 제14권1호
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• pp.13-20
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• 2012

In a normal x-ray examination, the cooperation of a patient in positioning greatly influences the improvement of work performance, the quality of the images and the reduction in time spent on the examination. An attempt was made to discover the connection between an examination information printout and the effects of the examination by informing the patient before the examination on the examination positions in order to increase the level of cooperation by the patient and by surveying the degree of satisfaction of the patient during the examination proceedings. An examination information printout was prepared on five positions that patients consider to be difficult while receiving normal x-ray examinations and were shown to 257 male and female patients between the ages of 30 to 79 who had visited this hospital between January 1 to February 29, 2012 or to a person who had accompanied the patients before the examination to research the degree of satisfaction regarding the printout. In addition, the examination explanation printout was given to Radiologic Technologists with over 1 year experience in this hospital to use while taking the x-rays and the degree of satisfaction was surveyed and it was examined if the increase of the degree of satisfaction had an effect on the reduction in the examination time. The patients who utilized the examination information printout revealed results of approximately a 7.8% higher degree of satisfaction among the patients who had previous experience receiving x-ray examinations compared to those were having an x-ray for the first time. In the age groups between 30 to 70 years of age, the age group in the 30's revealed the lowest level of satisfaction at approximately 69% and the group in the 50's showed the highest degree of satisfaction of 87.94%. In the survey of the Radiologic Technologists, 85% responded that they were satisfied. In the question that stated "Will the examination information printouts reduce the time involved in unnecessary conversations with the patients?," the responses showed a 95% degree of satisfaction. The degree of satisfaction was high over the examination information printout by both the patients and the Radiologic Technologists. Although the effects of examination time reduction varied based on the ages of the patients and physical conditions that they were in and could not be given measurement values, it was able to be seen through the survey that reduction of the unnecessary communication between the patient and the Radiologic Technologists contributed to the increase in the degree of satisfaction. As a result, both the patients and the Radiologic Technologists had an increased degree of satisfaction over the examination information printout and it was possible for improvements to be made in the quality of medical service provided as well. Nevertheless, it is considered that a more developed manual in terms of quality and quantity must be produced using a more systematic approach and design.

• Communications for Statistical Applications and Methods
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• 제19권4호
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• pp.619-628
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• 2012

Noise reduction is an important issue in the field of image processing because image noise lowers the quality of the original pure image. The basic difficulty is that the noise and the signal are not easily distinguished. Simple smoothing is the most basic and important procedure to effectively remove the noise; however, the weakness is that the feature area is simultaneously blurred. In this research, we use ways to measure the degree of noise with respect to the degree of image features and propose a Bayesian noise reduction method based on MAP (maximum a posteriori). Simulation results show that the proposed adaptive noise reduction algorithm using Bayesian MAP provides good performance regardless of the level of noise variance.