• 한국환경생태학회지
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• 제18권2호
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• pp.131-141
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• 2004

백두대간의 남덕유산∼소사해 구간 능선부에 대해 16개 조사지(단위면적 500$m^2$)를 설정하여 식생구조를 조사하였다. Classification(TWINSPAN)기법에 의한 군락분리를 실시 한 결과, 군락 I 에서 군락 IV는 모두 신갈나무가 우점종인 가운데 부수종별 차이가 있었으며, 군락V는 신갈나무-소나무군락으로 최종 5개 군락으로 분리되었다. 각 군락은 층위별 상대우점치를 이용하여 군락구조를 밝혔다. 기술통계분석결과 단위면적당(500$m^2$)평균출현종수는 27.8$\pm$7.5종, 평균출현개체수는 687.6$\pm$326.8주이었다.

• Transactions on Electrical and Electronic Materials
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• 제12권4호
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• pp.169-173
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• 2011

In this study, Al-N codoped p-type zinc oxide (ZnO) thin films were deposited on Si and homo-buffer layer templates in a mixture of $N_2$ and $O_2$ gas with ceramic ZnO:(2 wt% $Al_2O_3$) as a sputtering target using DC- magnetron sputtering. X-ray diffraction spectra of two-theta diffraction showed that all films have a predominant (002) peak of ZnO Wurtzite structure. As the $N_2$ fraction in the mixed $N_2$ and $O_2$ gases increased, field emission secondary electron microscopy revealed that the surface appearance of codoped films on Si varied from smooth to textured structure. The p-type ZnO thin films showed carrier concentration in the range of $1.5{\times}10^{15}-2.93{\times}10^{17}\;cm^{-3}$, resistivity in the range of 131.2-2.864 ${\Omega}cm$, and mobility in the range of $3.99-31.6\;cm^2V^{-1}s^{-1}$ respectively.

• 혜화의학회지
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• 제8권1호
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• pp.131-146
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• 1999

To evaluate the antitumor activity of Kamisagoonjatang(KST), Kami-jihwangtang (KJT) and Kamigoonjajihwangtang(KKJT), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against B16-F10, HT1080, SNU, and L1210, con-centration inhibiting cell growth up to below 50% of control was recognized at $10^{-3}g/ml$ of KKJT. 2. In cytotoxicity against A549, SK-OV-3, XF498 and HCT15, concentration inhibiting cell growth up to below 30% of control was over $400{\mu}g/ml$ of KKJT only and also over $200{\mu}g/ml$ against SK-MEL-2. 3. In Inhibitory effect on activity of DNA topoisomerase I, the $IC_{50}$ was shown $200-400{\mu}g/m{\ell}$, of KST, over $400{\mu}g/m{\ell}$ of KJT and $100-200{\mu}g/m{\ell}$ of KKJT. 4. The T/C% was 122.8 in KJT, 127.4 in KST and 158.4 in KKJ-Ttreated group in S-180 bearing ICR mice. 5. In hematological changes in S-180 bearing ICR mice, numbers of WBC were decreased significantly in KJT and KKJT treated groups as compared with control, whereas those of platelet were increased with no significance in all groups as compared with control. From above results it was concluded that KKJT could be usefully applied for the prevention and treatment of cancer.

• 영어어문교육
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• 제8권2호
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• pp.131-150
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• 2003

The purpose of this paper is to provide two levels of conceptualization of a category such as an absolute category in semantic level and a relative category in pragmatic level on the basis of Aristotelian category theory and prototype category theory. I do not intend to criticize classical category theory and prototype category theory but to show that these two types of category are applied to the different world. Aristotelian categorization is an absolute category because it is based on the possible world called the meta-world and it has an absolute truth value. The members of an absolute category is presented as a set. There is a clear boundary between members and non-members because they are distinguished by the absolute criteria An absolute category is semantic conceptualization. This absolute category is changed into a relative category when it is applied in the real world. A relative category which corresponds to a prototype category is based on the real world called the object world and it has a relative truth value. Here individuals are categorized by the cognition and perception of human beings. A relative category is pragmatic conceptualization. In conclusion, while classical categories which are called absolute categories represent sentence meaning, prototype categories which are called relative categories represent utterance meaning.

• Clinical and Experimental Reproductive Medicine
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• 제17권2호
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• pp.145-151
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• 1990

This study was carried out to elevating the pregnancy rate in infertile patient by Gamete intrafallopian transfer (GIFT). The GIFT program was performed from July 1988 to June 1990. Of the 131 cycles, the mean age of patient was 31.6 years and the mean duration of infertility was 5.3 years. 41 patients became pregnant, for a pregnancy rate of 31.3%. 5 preclinical abortions and 6 clinincal abortion was occured. 2 ectopic pregnanices and 1 combined pregnancy were occured. 7 twin pregnancies and 1 triplet were occured (multiple pregnancy rate;22.2%). 11 pregnancies were term delivered, 17 are ongoing pregnancies. GIFT may be considered as an alternative to in vitro fertilazation in infertility cases in which at least one fallopian tube is patent.

• Journal of Magnetics
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• 제4권4호
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• pp.131-135
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• 1999

The HDDR characteristics of the Nd-Fe-B-type isotropic and anisotropic HDDR alloys were investigated using three types of alloys: alloy A $(Nd_{12.6}Fe_{81.4}B_6), alloy B (Nd_{12.6}Fe_{81.3}B_6Zr_{0.1}), and alloy C (Nd_{12.6}Fe_{68.8}Co_{11.5}B_6Ga_{1.0}Zr_{0.1}$). The alloy A is featured with the isotropic HDDR character, while alloy B and C are featured with the anisotropic HDDR character. Hydrogenation and disproportionation characteristics of the alloys were examined using DTA under hydrogen gas. Recombination characteristics of the alloys were examined by observing the coercivity variation as a function of recombination time. The present study revealed that the alloy C exhibits slightly higher hydrogenation and disproportionation temperatures compared to the alloy A and B. Recombination of the anisotropic alloy B and C takes place more rapidly with respect to the isotropic alloy A. The intrinsic coercivities of the recombined materials rapidly increased with increasing the recombination time and then showed a peak, after which the coercivities decreased gradually. The degraded coercivity was, however, recovered significantly on prolonged recombination treatment. Compared with the isotropic HDDR alloy A the anisotropic HDDR alloy B and C are notable for their greater recovery of coercivity. The significant recovery of coercivity was accounted for the in terms of the development of well-defined smooth grain boundary between the recombined grains on prolonged recombination.

• 한국조경학회지
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• 제28권3호
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• pp.13-24
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• 2000

In urban area, urban forests work as an ecological center that mitigates the environmental pollution of the area. In order to maintain the ecological function of a forest, the management method should be established based on ht through investigation of the vegetation structure of the forest. In this study, the vegetation structure of Namsan in Kyungju area was investigated in order to study the ecological value of Namsan and to suggest a desirable management alternative. 21 plots were selected as survey areas. Using the TWINSPAN technique, the forest of Namsan was classified into four communities: Quercus serrata community(I), Castanea crenata-Q. serrata-Q. mongolica community(II), Pinus densiflora community(III) and P. densiflora-P. rigida-Robinia pseudoacacia community(IV). The survey results were summarized by five: 1) the distribution of vegetation showed 2) P. densiflora was the absolutely dominant species in Namsan, 3) number of the average species was 12.6$^{\circ}$$\pm$3.1, 4) number of individual was 131.1$^{\circ}$$\pm$47.8 per a plot(100$m^2$), 5) the results of annual ring analysis revealed that the age of P. densiflora in Namsan was about 3 0$^{\circ}$~60$^{\circ}$years old. From the above results, it was found out that the forest has two problems. One thing is maintenance of P.densiflora against succession, another is artificial forest dispersion. The problems of Namsan forest management will be solved with further studies related.

• 한국조경학회지
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• 제24권4호
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• pp.123-131
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• 1997

Since the industrial revolution. the growth of cities has been especially apid and the rate of ulbanization has been high. This urban development is encroaching on the natural environment because the cities are developed with not only residential estates, industrial area and buildings but also with infrastructure. The surface area of the city is sealed ,with pavement whereas nature is disturbed and modified. The hydrological cycle in the city is inf1uenced by the change of land use I. e., from forest to agricultural land, talc draining of wetlands and above all the increase of built-up areas. The surface retention and interception of precipitation in the city is reduced. because the surface area is now smooth and solid. The characteristics of the hydrological cycle in the city are increased runoff, reduced evapotranspiration and infiltraction . We have too much faith in technology although it may cause more unforseen problems. We build more river banks and 'emulation dams and straighten rivers and streams in order to protect ourselves from disasters.. However. the results of hose developments are often higher$.$ water levels, the disturbance of aquatic ecosystems and the reduction of biodiversity. Therefore, we should examine problems from the hydrological cycle in cities and study a natural system as close cities to nature as possible. This paper shows the problems caused by the hydrological cycle in the city. The ecology-oriented method and design must be used in order to protect our environment from dicturbance.

• 한국정보전자통신기술학회논문지
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• 제1권2호
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• pp.131-136
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• 2008

인터넷 네트워크를 통한 상호연결망에서 전체시스템의 성능향상을 위해서는 메시지 전송 지연시간을 줄이는 방법으로 수행된 연구는 정보와 데이터 유통경로로서 통신망이 네트워크로 구축된 접속 장치들로 중계기, 브리지, 라우터, 게이트웨이, TCP/IP(Transmission Control Protocol/Internet Protocol)프로토콜에 이르게 되었다. 여기서 TCP/IP 프로토콜 제 3계층인 사용자 데이터 프로그램 프로토콜(UDP)과 전송 제어 프로토콜(TCP)의 전송제어 계층에서 버퍼 캐시를 사용하지 않으므로 통신 속도를 줄일 수 있는 무 복사(zero-copy)로부터 소프트웨어 통신 지연시간을 다루어 통신 성능을 개선하려는 것이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.128-131
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• 2003

The number of grain is determined based on Poisson distribution in respectively different active channel and it is converted to grain size which affects to the mobility and threshold voltage. the acquired data is applied to the SPICE for observing the variation of I-V characteristic with several channel lengths. we can confirm the effect on device.