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      • 복호화된 H.236 영상의 화질 향성 기법

        방성식,최우영 명지대학교 대학원 1997 대학원논문집 Vol.1 No.-

        In this paper, we proposed a technique for minimizing blocking effects and mosquito noises which are major causes of image degradation in H.263-based transmitted images. Since the blocking effects occur in the uniform region like background and the mosquito noises occur in the non-uniform rigion like edge neighborhood, we proposed an algorithm to divide image into uniform and non-uniform regions and a filtering algorithm that is adequate for each noise. To reduce the blocking effects, 4-pixel non-linear filter is proposed to get the better performance in both subjetive and objective respect. 5-pixel median filter is used for reducing mosquito noises. In simulation result, the proposed method shows higher PSNR of 0.02~1.01dB and better subjective test, results in comparison with existing methods.

      • 순무(Brassica campestris ssp. rapa) 뿌리로부터 지질화합물의 분리 및 동정

        방면호,오영준,유종수,한민우,정해곤,정태숙,최명숙,이경태,김세영,백남인 경희대학교식량자원개발연구소 2007 硏究論文集 Vol.26 No.1

        순무 뿌리로부터 활성 물질을 분리 동정 하기 위하여 80% MeOH 수용액으로 추출하고 이를 여과, 감압 농축하여 MeOH추출물을 얻었다. 이를 EtOAc분획, n-BuOH분획, H_(2)O분획으로 나누었으며, EtOAc분획에 대해 silica gel column chromatography를 실시하여 3종의 지질화합물을 분리 정제하였다. ^(1)H-NMR, ^(13)C-NMR, DEPT spectrum 및 Mass spectrum등을 통하여 palmitic acid methyl ester(compound 1), linolenic acid methyl ester(compound 2), linoleic acid methyl ester(compound 3)으로 구조를 결정하였다. In order to isolate and identify the active compound from the Brassica campestris ssp rapa, the roots and the root skin were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and H_(2)O. From the EtOAc fraction, three compounds were isolated through the repeated silica gel column chromatographies. From the result of spectral data including NMR and MS, the chemical structures of the compound were determined as palmitic acid methyl ester (compound 1), linolenic acid methyl ester (compound 2), linoleic acid methyl ester (compound 3).

      • 의공학적 기법에 의한 간병변의 검진과 치료 경과의 정량 : 초음파 신호처리 Ultrasound Signal Processing

        우광방,진영민 연세대학교 대학원 1985 延世論叢 Vol.21 No.4

        This study was aimed to develop the technique of signal processing which enables the improvement of the resolution of A-scan in the image of ultrasound sonogram to human organs, including patients with liver disease. The ultrasound was transmitted to the phantom composed of hard rubber(63×60×6mm), glycerin(60×60×13mm) and gluss(60×60×4mm), and the spectral extrapolation algorithm was developed and utilized to improve the resolution of A-scan out of the region of finite frequency band and to find the location as well as the reflection coefficient of the reflector from the image of A-scan. The results from the analysis of ultrasound image by the spectral extrapolation include the following: 1. For the reflected signal containing no noise, the resolution of the A-scan signal was not influenced by the duration of transmitted signal and was limited only by the sampling interval. 2. For the reflected signal containing noise, the location and the reflection coefficient of the reflector with depth of 0.5mm of the phantom were detected when the ultrasound was applied with center frequency of 2.25MHz. 3. When the level of noise in the reflected signal leas reduced, the resolution of the signal was improved so that the depth of the reflector less than 0.5mm was detected. It is expected that this technique will be of considerable value to the analysis of the data obtained from the patients with liver disease.

      • KCI등재후보

        자색고구마가 사염화탄소 투여에 의한 흰쥐의 간손상 보호에 미치는 영향

        조영자,김현아,방미애,오용비,정병춘,문윤호,정우진 한국식생활문화학회 2003 韓國食生活文化學會誌 Vol.18 No.3

        The purpose of this study was to investigate the effects of dietary purple sweet potato(lpomoea batatas) powder on serum lipid levels and antioxidative enzymes in normal and pretective effect on hepatotoxicity rats induced by carbon tetrachlolide. Four groups of rats (3-week-old inbred Sprague-Dawley male rats) were normal rats fed control diet(C)_(1) induced hepatotoxicity rats fed control diet(EC)_(1) normal rats fed purple sweet potato diet(P), and induced hepatotoxicity rats fed purple potato sweet diet(EP). Rats were induced by single injection of 50% carbon tetrachloide(0.1 mL/100 g B.W., i.p.). The rats were fed ad libitum each of the experimental diet for 5 weeks. After 5 weeks the rats were sacrificed and activities of antioxidant enzymes and lipid peroxidation products were determined in their liver homogenates. But serum concentrations of lipid was not significant in all groups. Serum alanine aminotransferase(ALT/GPT) and aspartate aminotransferase(ALT/GPT)of the EC and EP groups were heigher than the C and P groups. The hepatic glucose 6-phosphatase(G9Pase) activity of the group fed purple potato diet(P) was lower than the other groups(p<0.05). However, The glutathione peroxidase(GPx) activities was not statistically different between the groups. Renal glutathione S-transferase(GST) activity of the EC and EP groups were lower than the C and P groups(p<0.05). In conclusion, these results suggest that purple sweet potato is believed to be possible protective effect on hepatotoxicity rats induced by carbon tetrachlolide.

      • KCI등재

        Trametes versicolor에 의한 상수리나무의 분해형태

        유태방,윤민호,최우영,이종신 충남대학교 농업과학연구소 2001 농업과학연구 Vol.28 No.2

        백색부후균 Trametes versicolor(CV5) 균주에 의한 wood lignin의 분해능을 조사하였다. CV5는 활엽수와 침엽수에 속하는 여러 수종의 프로토 리그닌 분해 시 활엽수에 한해서 분해되는 특성을 보였으며, 특히 상수리나무에서 33.5%의 가장 높은 리그닌이 분해되었다. 리그닌 분해에 관련된 phenoloxidase 분비능을 Bavendamm 시험을 통해 검토한 결과 CV5는 지금까지 연구된 우수 백색 부후균과 같은 유사 반응 형태를 나타내고 있음을 확인하였다. 또한 상수리 목재 chip표면에 CV5의 균사가 생육하면서 목재조직이 부후된 상태를 주사전자 현미경으로 관찰한 결과 목섬유 및 도관에서 균사의 침투와 목재조직의 분해를 확인하고 리그닌에 대한 높은 선택적 분해력을 갖고 있음을 구명하였다. Trametes versicolor(CV5) selected as a white-rot fungus with strong lignin degrading activity, in the previous paper, was investigated on a properties of degradation of wood lignin. Lignins of hardwoods, especially oak(Querous acutissima carruth) an paulownia (Paulownia coreana Uyeki) were considerably delignified by the CV5, however, softwoods used in this experiment were not delignified. Bavendamm's reaction was positive with several phenols on agar plates for the confirmation of a phenoloxidase secreted Through the morphologies of decayed wood chip observed with the aid of scanning electron microscopy, it was found that the hypha of CV5 penetrated the ray cells and vessels caused separation of the wood cellulose.

      • KCI등재

        화학 이론의 전통 과학적 연구

        박서영,정원우,방경곤,김용수,문장수,이우붕 慶北大學校 師範大學 科學敎育硏究所 2007 科學敎育硏究誌 Vol.31 No.-

        According to the system of the oriental traditional science, everything has to be harmony and interact with one another. The fundamental notions of the traditional natural philosophy are "do(doctrine)", "taegeuk(the great absolute)", "yin-yang," "five primary substance", "four events", and "eight signs for divination". Taegeuk, especially, explains the formation and the death of all things in the universe through circulation of yin-yang, and shows the balance of nature and universe. Yin-yang, relative ideas produces four events, and four events also is divided into the eight signs for divination. 'four events', 'eight signs for divination' like 'yin-yang' indicates the cycle of nature. The essential notions of the traditional science are not different from those of modern chemistry. Taegeuk which is the origin of all things in the universe means the situation of harmony and balance through ceaseless circulation and connotes dynamic equilibrium on neutralization that chemical reaction get to. A number of opponent concepts such as acid-base, oxidation-reduction, atomic nucleus-electron are given an explanation by ying-yang(the positive and negative) that reaches Taegeuk through chemical bonding or reaction over simple antagonistic relationship. 'Yin-yang', 'four-events', 'eight signs for divination' do not imply a substance or a phenomenon in itself but the properties of them. That is why it is possible to see into various chemical concepts like a relative strength of acid-base, groups of periodic table with traditional scientific philosophy. We have regretfully neglected studies in traditional science. It is time to perform the concrete work connecting theory of traditional science with that of modern science for advisable appreciating of traditional science. Moreover, It is necessary to do research and development of educational programs or teaching-learning materials using the traditional science properly. 동양 과학 철학이나 자연 철학은 태극,음양오행,사상팔괘를 이용해 우주 만물의 운동과 자연의 순환을 설명하는데 있어 그 학문적 우수성을 부인할 수 없으나 현대의 화학식이나 수식이 현상을 미시적 관점에서 구체적으로 설명할 수 있는 것과는 달리 전통 과학이론은 거시적 관점에서 그 전체적 흐름만을 나타낸다는 한계를 가지고 있다. 그럼에도 불구하고 태극,음양오행 그리고 사상팔괘론을 중심으로 한 전통 과학 이론은 현대인들에게 과학에 대한 새로운 시각을 제공함으로써 무분별하고 비윤리적인 과학 기술 활용으로 인한 전 지구적인 문제들을 해결하는데 있어 핵심적인 역할을 수행함은 물론 오늘날의 한국 과학이 한 걸음더 전진하는데 이바지 할 수 있을 것이다. 그러므로 서구 중심의 기존의 과학문명에만 머무를 것이 아니라 동양의 전통 과학 철학을 연구하여 민족의 과학 체계를 수립하고 과학의 토착화를 이루어야 한다. 이를 성공적으로 수행하기 위해서는 전통 과학과 현대 과학 사이에 다리를 놓는 구체적인 작업이 본격적으로 진행되어야 한다. 기본적인 화학 개념들을 전통 과학적 관점에서 재해석 하는 것은 물론이고 더 나아가 전통 과학의 이론을 이용하여 화학 반응 과정을 구체적으로 설명하려는 시도가 필요할 것이다.

      • KCI등재
      • CBD으로 제작한 In:Cd_(1-x)Zn_(x)S/CdTe 태양전지의 전기적 특성에 관한 연구

        심재선,송우창,방영근,김남석,임창민,장현 三陟大學校 2006 論文集 Vol.39 No.-

        CdS thin films have been widely used a window material in heterojunction solar cells. In solar cell systems, where CdS thin films have been proved to be useful, partial substitution of Zn for Cd increases the optical window of the hetero-junction and also the diffusion potential. In this thesis, effects of the thickness of indium films and the annealing temperature on structural, optical and electrical properties of chemically deposited CdZnS films for the efficiency of the Cd_(1-x)Zn_(x)S/CdTe solar cells were investigated. Cd_(1-x)Zn_(x)S films were grown by chemical bath deposition (CBD), which is a very attractive method for low-cost and large-area solar cells. The open circuit voltage of Cd_(1-x)Zn_(x)S/CdTe solar cells increased due to reduced electron affinity difference between Cd_(1-x)Zn_(x)S and CdTe films. However, the conversion efficiency of Cd_(1-x)Zn_(x)S/CdTe solar cell decreased because of the higher series resistance(R_(s)) than CdS/CdTe solar cell. The series resistance and conversion efficiency of Cd_(1-x)Zn_(x)S/CdTe solar cell were improved by using indium-doped Cd_(1-x)Zn_(x)S films as window layer. Cd_(1-x)Zn_(x)S/CdTe solar cells fabricated with optimal conditions exhibited V_(oc)=630mV, J_(sc)=38.89mA/㎠ , FF=0.53, and η=13.2%

      • KCI등재

        용융 금속 TSV 충전을 위한 저열팽창계수 SiC 복합 충전 솔더의 개발

        고영기,고용호,방정환,이창우,Ko, Young-Ki,Ko, Yong-Ho,Bang, Jung-Hwan,Lee, Chang-Woo 대한용접접합학회 2014 대한용접·접합학회지 Vol.32 No.3

        Among through silicon via (TSV) technologies, for replacing Cu filling method, the method of molten solder filling has been proposed to reduce filling cost and filling time. However, because Sn alloy which has a high coefficient of thermal expansion (CTE) than Cu, CTE mismatch between Si and molten solder induced higher thermal stress than Cu filling method. This thermal stress can deteriorate reliability of TSV by forming defects like void, crack and so on. Therefore, we fabricated SiC composite filling material which had a low CTE for reducing thermal stress in TSV. To add SiC nano particles to molten solder, ball-typed SiC clusters, which were formed with Sn powders and SiC nano particles by ball mill process, put into molten Sn and then, nano particle-dispersed SiC composite filling material was produced. In the case of 1 wt.% of SiC particle, the CTE showed a lowest value which was a $14.8ppm/^{\circ}C$ and this value was lower than CTE of Cu. Up to 1 wt.% of SiC particle, Young's modulus increased as wt.% of SiC particle increased. And also, we observed cross-sectioned TSV which was filled with 1 wt.% of SiC particle and we confirmed a possibility of SiC composite material as a TSV filling material.

      • 性別 및 年齡에 따른 體格과 體力의 特性과 變化에 關한 縱斷的 硏究Ⅱ : Emphasised on College Men of Department of Physical Education 體育專功 大學生을 中心으로

        金尙國,姜東洹,張周鎬,金昇一,徐再均,金耕知,孫斗玉,鮮于攝,崔榮烈,尹宇相,金亨燉,方永鎭,朴英震,柳在忠 慶熙大學校 體育科學大學 1989 體育科學論叢 Vol.- No.2

        The purpose of this study was to compare the characteristics, change in physique and physical function of college students majoring physical education and Taekwondo (454 males and 64 females of age groups ranging from 18 to 26). The results are as following: 1. The male group of 23yrs old in physical education showed highest values in 7 items(Weight, Chest Girth, Fore Arm Girth, Thigh Girth, Calf Girth, Scapular Skinfold Thickness and Suprailiac Skinfold Thickness). 2. In the Physical function, the male group of 18yrs old showed highest values in Power, Flexibility, and then 21yrs old at Back Strength, Vital Capacity, and 23yrs old at Grip Strength, and 25yrs old at Blood Pressure, respectively. 3. In the physique, the male group of 22yrs old showed highest values in Weight, Chest Girth, Thigh Girth, Calf Girth, and then 24yrs old Upper Arm Girth, Fore Arm Girth, and 19yrs old at Height, Upper Limb Length, respectively. 4. In Physical Function, the 22yrs old showed highest values in Back Strength, Vital Capacity, and then 23yrs old at Side Step, Trunk Extension, but 18yrs old showed lower Values in Grip Strength, Side Step, Vital Capacity and Blood Pressure. 5. The female group of 22yrs old showed highest values in 8 items(Height, Sitting Height, Waist Girth, Upper Limb Length, Lower Limb Length, Skinfold Thickness), and then 18yrs old at 5 items (Weight, Upper Arm Girth, Fore Arm Girth, Thigh Girth, Calf Girth), respectively. 6. In the physical function, the 22yrs old showed highest Values in Grip strength, Back Strength, Power, 5 Minute Run, and 18yrs old at flexibility, Harvard Step Test, respectively. 7. In the change of the physique for two years(1988-1989) in the male group, majoring Physical education the 22yrs old showed increase in 4 items, and the 20yrs old in 3 items, but 18yrs old showed decrease in 3 items. 8. In the change of the physical function for two years in the male group, the 20yrs old showed increase in 4 items, and the 21, 25, 26yrs old in 3 items, but the 19yrs old showed decrease in 6 items, and 18, 22 yrs old in 5 items, respectively. 9. The change of the physique for two years in all female group, of 18, 19, 20, 21yrs old showed increase in 11 items except Skinfold Thickness. 10. In the change of physical function for two years in female group, the 18yrs old showed increase in 3 items, and then 20yrs old in 5 items, but 19, 22yrs old decreased 12 items, respectively. 11. The highest significant difference in physique between male and female was found in weight(mean Value 17.5%), and the lowest difference was found Thigh Girth, Calf Girth(1,3%), Upper Limb Length, Lower Limb Length(2.5%). 12. The Highest difference in physical function was Strength (mean Value 40%), Vital Capacity (33%), Power(22%), but Lower Trunk Flexion, Foot Balance(3.4%). 13. In the difference of Physique and physical function between physical education major and taekwondo major, the physical education showed higher values in skinfold Thickines (mean Value 16.5%), Weight, Waist Girth(4.7%) and Strength(33%), Endurance(5.6%), but subjects majoring Taekwondo showed higher values in Flexibility and Foot Balance. 14. In all male groups, Waist Girth, Scapular Skinfold Thickness, Back Strength, Sargent Jump, Trunk Extension and Diastolic Blood Pressure were showed a significantly related at 0.001 level.

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