• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.196-199
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• 2000

마이크로파용 세라믹 유전체로 사용되는 MgTiO$_3$-CaTiO$_3$계 유전체에 Li을 첨가하여 이때 얻어지는 마이크로파 유전특성과 소결특성에 대하여 알아보았다. 94MgTiO$_3$-6CaTiO$_3$으로 주조성을 고정시키고 여기에 Li$_2$CO$_3$를 Li원자 기준으로 0 ~ 10 mol% 범위 안에서 첨가하여 1200~140$0^{\circ}C$의 온도에서 4시간 소결하였다. Li의 첨가량이 적을 때에는 유전체의 품질계수와 유전상수가 모두 감소하였으나 약 lmol% 이상 되면 다시 증가하였으며, 이후 첨가량이 과도해지면 다시 서서히 감소하는 경향을 볼 수 있었다. 1.0 ~ 3.0 mol%의 첨가량 범위 안에서 Li은 MgTiO$_3$-CaTiO$_3$계 유전체의 품질계수를 증가시켜주는 역할을 하는 것으로 나타났다 1.5mol%의 Li을 첨가하고 1275$^{\circ}C$에서 4시간 소결한 시편에서 유전상수는($\varepsilon$$_{r}$) 20.0, Qf는 78,000 그리고 공진주파수 온도계수($\tau$$_{f}$)는 -1.6ppm/$^{\circ}C$의 결과를 얻을 수 있었다.다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.71-71
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• 2022

들깨는 잎은 채소, 종자는 기름과 향신료로 이용하는 특용작물로 국립농업과학원 농업유전자원센터에는 국가등록 3,066자원을 보유하고 있다. 들깨 유전자원의 보존기간과 방법에 따라 종자 활력의 차이가 어떻게 변화했는지 알아보기 위해 농업유전자원센터 보존 중인 들깨 유전자원의 발아율을 조사하였다. 온도는 4도, -18도, 밀폐용기 보관하여 보존한 들깨 종자를 10년 보존 후 발아조사를 수행하였다. 발아환경은 페트리디쉬에 거름종이를 깔아 멸균수로 수분을 공급하고, 종자를 50립씩 2반복 치상 후 20도에서 7일, 14일에 조사하였다. 4도에서 보존한 들깨 577자원은 발아율이 85%이상인 자원이 184자원으로 나타났다. -18도에서 보존한 들깨 725자원은 발아율이 85%이상이 자원이 329자원으로 나타났다. 세계적으로 식물유전자원은행에서 양호한 발아율의 기준으로 85%를 사용하는데, 4도 보존 들깨 유전자원들은 조사한 자원의 32%가 양호하였고, -18도 보존 자원들은 45%가 발아 기준을 만족하였다. 들깨유전자원을 10년 주기로 발아율을 조사한 결과 -18도 보존 종자의 발아율이 4도 보존 종자보다 기준발아율이 13% 우수하였으나 두 처리 모두 85% 기준발아율을 만족하는 자원이 50%이하로 나타났다. 본 연구결과는 들깨유전자원을 4도, -18도에서 장기 보존할 때에 종자 활력 예측 및 활력 모니터링 연구에 도움이 될 것이다.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.328-335
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• 2013

The National Agrobiodiversity Center is the nodal agency assigned as the National Agricultural Genebank of the Rural Development Administration. Its main role is to collect, conserve, evaluate and distribute plant genetic resources. As of 2010, NAC has distributed a total of 380,981 accessions in the last 20 years (1991-2010) or an average of about 19,000 accessions per year. To meet customers' demands for germplasm and derive quality improvements, a mail survey in 2011 was conducted among the genetic resource users in 2010. Most of the clients obtained information on the germplasm conserved in the national genebank from the NAC website or NAC staff, and they sought specific traits in the samples. Most users received the materials within 15 days, and wanted useful data together with genetic resource. Korean landrace was the most frequently requested accessions. According to the survey results, it is supposed that useful genetic resources should be preferentially collected and their characterization/evaluation should be strengthened to enhance the utilization of genetic resources.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.38-55
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• 2009

Purpose: This study was undertaken to provide the framework for development of a genetic counseling training program, and an accreditation and certification process suitable for non-M.D. genetic counselors in Korea. Materials and Methods: Global standards of genetic counseling curriculums, training program accreditation (TPA), and the certification process for genetic counselors (CPGC) in the U.S.A and Japan were reviewed, and a questionnaire survey was performed to elicit opinions among health-care providers including physicians, nurses, technicians, researchers, and educators. In addition, input from professional communities, including the Korean Society of Medical Genetics (KSMG) and Institute for Genetic Testing Evaluation, was sought in formulating the framework of this study. Results: Comparison of U.S.A. and Japan educational systems showed similarities in curriculum, accreditation, and certification programs. Analysis of 117 respondents opinions showed a high level of agreement in the area of global standards; 88% indicated that KSMG should be in charge of TPA and CPGC, while 77% favored a certification exam composed of both written exam and interview components. Conclusion: Based upon this study we propose that the KSMG should be in charge of providing the TPA and CPGC for non-MD genetic counselors. Requirements for the entrance to a Master's degree genetic counseling program should be open to successful four year undergraduate students in all areas, provided the candidates demonstrate the abilities to master the graduate level of study in human genetics, clinical genetics, statistics, psychology, and other required subjects. Eligibility for certification should include qualified candidates of genetic counseling with no formally approved education, but a sufficient amount of clinical experience, in addition to accredited program graduates. Certification examinations should be carried out every two years and the certification should be good for five years, as is the case in Japan.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.134-139
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• 2000

Ternary system of 40PMN-30PT-30PMW was prepared by using different reaction process. The PMN-PT was synthesized firstly, then it reacted to $PbWO_4$ as PbO and $WO_3$ sources. The dielectric constants were dependent on the density of sintered body and decreased with sintering temperature above $950^{\circ}C$. The highest dielectric constant was 24,000 in a sample sintered at $950^{\circ}C$ with the dielectric loss of 3 %. The temperature dependence of the dielectric constant were decreased with the increase of sintering temperature due to the appearance of double peak maxima. The lowest change in dielectric constant was -37-0 % from -55 to $125^{\circ}C$in a sample sintered at $1150^{\circ}C$ with dielectric constant of 9,900 at room temperature.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.50-50
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• 2001

혈액형을 지배하는 유전자는 진화에 대하여 중립적인 작용을 하고 있어서 집단의 유전적 구조의 특성 파악, 계통분류학 등에 많이 응용되고 있다. 본 연구는 칡소에 대한 유전학적 특성을 구명하고자 혈액형 분석기술을 응용하여 실시하였다. 공시동물은 (주)한경게놈텍 목장에서 사육중인 외모적으로 칡소의 특징을 보이는 25두를 이용하였다. 혈액은 경정맥에서 헤파린 처리된 진공 채혈관에 무균적으로 채취하여 혈장, 백혈구 및 적혈구로 원심분리한 후 냉동 혹은 냉장 보관하여 각 실험에 이용하였다. 적혈구 항원형의 검출은 2% 적혈구 부유액과 축산기술연구소에서 생산된 항혈청 11종을 이용하여 용혈반응으로 실시하였고, 혈액단백·효소를 지배하고 있는 6개의 유전자 좌위에 대하여 전분 혹은 포리아크릴 아미드겔 전기영동으로 다형 검출을 실시하였다. 용혈반응으로 검출한 적혈구 항원형의 반응양상은 검사한 11종의 항체에 대하여 6종은 50%이상의 개체에서 양성반응을 보였다. 이와 같은 결과는 일반 한우에서 보이는 양성반응율보다는 높은 것으로 판단되어진다. 전기영동법으로 분석한 6개의 혈액단백·효소 지배 유전자 좌위 중 ALB좌위을 제외한 5개 유전자 좌위에서 다형이 관찰되었다. HB, AMY-1, GC 및 PTF-2 유전자 좌위는 2개의 대립유전자가 관찰되었고, TF 유전자 좌위는 4개의 대립유전자가 관찰되었다. 표 1에서 같이 칡소에서 관찰된 각 유전자 좌위의 대립유전자 빈도의 구성은 일반적인 한우와는 상이한 결과를 보였으나 평균 이형접합도는 칡소가 0.438, 일반한우가 0.442로 계산되어 유전적 변이성은 유사한 것으로 추정되었다. 이상의 결과로 본 연구에서 분석한 칡소는 다른 한우집단과는 상이한 유전적 구조를 가지고 있으나, 유전적 다형성은 비교적 높은 것으로 시사되었다. 보다 정확하고 많은 량의 유전정보 수집을 위하여 Microsatellite DNA 및 모색 관련 유전자를 분석할 필요성이 있을 것으로 사료된다.(Table Omitted)

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.25-37
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• 2009

Hereditary peripheral neuropathies can be categorized as hereditary motor and sensory neuropathies (HMSN), hereditary motor neuropathies (HMN), and hereditary sensory neuropathies (HSN). HMSN, HMN, and HSN are further subdivided into several subtypes. Here, we review the most recent findings in the molecular diagnosis and therapeutic strategy for hereditary peripheral neuropathies. The products of genes associated with hereditary peripheral neuropathy phenotypes are important for neuronal structure maintenance, axonal transport, nerve signal transduction, and functions related to the cellular integrity. Identifying the molecular basis of hereditary peripheral neuropathy and studying the relevant genes and their functions is important to understand the pathophysiological mechanisms of these neurodegenerative disorders, as well as the processes involved in the normal development and function of the peripheral nervous system. These advances and the better understanding of the pathogenesis of peripheral neuropathies represent a challenge for the diagnoses and managements of hereditary peripheral neuropathy patients in developing future supportive and curative therapies.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.3
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• pp.56-63
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• 2003

A silent type ozone generator using water surface has been studied and improved its ozone generation characteristics by installing dielectric heads in the just under the surface of the wale- At this time, different permittivitis of dielectric beads were used to change the discharge condition of water surface. The current-voltage characteristics and characteristics of ozone generation quantity of the test system were investigated and discharge photos of glass beads were observed The height of Taylor cone may be the cause of the discharge bridge to decrease the ozone generation on the discharge spacing. In this study, the hight of Taylor cone could be controlled greatly by installing dielectric beads just under the water surface. Therefore a higher ozone generation also could be obtained. As the permittivity of dielectric material increased. discharge starting voltage was advanced and maximum 110 ppmy of ozone was generated by using the ferroelectric ball.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.95-104
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• 2009

This study was conducted to evaluate the relationship between the dielectric constant and air void of asphalt concrete. Standard specimens that have air voids of various range $(0%{\sim}20%)$ were used to measure the dielectric constant using parallel plate method that measures low frequency dielectric constant. From the tests, dielectric constant of asphalt concrete was tend to decrease as the frequency was increased, and the decrement slope was varied with the types of asphalt binders. Dielectric constant was decreased linearly as air void was increased from zero to twenty percent. Consequently, the effect of temperature and moisture content on dielectric constants of asphalt concrete was evaluated to develop the standard curve between dielectric constant and air void of asphalt concrete. The standard curve developed in this study can be used to calibrate or develop the algorithm of non-destructive density gauge.

• Journal of Soil and Groundwater Environment
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• v.9 no.3
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• pp.1-11
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• 2004

To evaluate the applicability of dielectric constant measurement method on the geoenvironmental investigation of subsurface contaminated by landfill leachate, the analysis on dielectric characteristics of sand containing contaminated pore water by landfill leachate was performed. The separate real and imaginary parts of dielectric constant were investigated in the frequency range of 75kHz to 12MHz. The real part of dielectric constant increased at the lower frequency wherea the real part of dielectric constant decreased at the higher frequency as the concentration of leachate increased. These results can be explained by the frequency dependence of space charge polarization and orientation polarization. The imaginary part of dielectric constant on the contaminated sand with leachate increased with their concentration for whole frequency range. These results are caused by the increase of energy loss due to the enhancement of conduction in soil with leachate concentration. The results in this study indicate that the dielectric constant measurement method has potential in evaluating the contaminated soil and pore water by landfill leachate.