• Title/Summary/Keyword: 반지

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Ecological Characteristics of Picea abies Plantation in Comparison with Fagus sylvatica Population (유럽너도밤나무 군락과 독일가문비 조림지의 생태특성 비교)

  • Lee, Young-Geun;Cho, Hyun-Je
    • The Korean Journal of Ecology
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    • v.23 no.5
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    • pp.377-382
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    • 2000
  • Picea abies plantation in Mt. Eifel, Germany was studied phytosociologically, with special reference to species composition, structure, ecology and dormancy form, comparing to those of Fagus sylvastica population that once dominated the P. abies plantation. Thirteen plant species appeared on average. According to their ecological distribution, they were classified into three groups, F sylvastica forests, natural coniferous forests and bare-land after clear-cutting. In Luzulo-Fagetum population, Luzula luzuloides was the dominated species while in P. abies plantation was dominated by Avenella flesuosa. In assessment of herbaceous plants by indicator species of Ellenberg, increasing number of shade-intolerant species and acid-tolerant species occurred. In analysis of plant dormancy form, species of Chamaephytes, Phanerophytes and Hemikryptophytes increased, while that of Geophytes decreased. As a result, we found P. abies plantation unstable in ecological aspects.

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Characteristics of an Optical Waveguide with Two Identical Elliptical Structures (두 개의 동일한 타원형 구조를 지닌 광 도파관의 특성)

  • Jang, SeongHo;Chung, SangHo;Yi, SeungHwan
    • Journal of the Korean Institute of Gas
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    • v.18 no.2
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    • pp.48-54
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    • 2014
  • A unique optical waveguide structure is proposed to enhance the optical characteristics of alcohol screening sensors. This structure is then simulated. The structure consists of two elliptical waveguides that have a common focus to one side and has an IR source and detector at each of the other focal points of the ellipses. When the angle between the two elliptical waveguides is increased from 30 degrees to 90 degrees, the maximum level of irradiance is greatly decreased, falling from $2.23{\times}10^6 W/m^2$ to $5.74{\times}10^5W/m^2$. However, the diameter of the incident rays is at a minimum of 1.86mm and the total incident flux is less than 10% lower when compared to the structure at $90^{\circ}$. It can be seen from the simulation results that this structure might enhance the sensitivity of an optical gas sensor which has a large absorption wavelength.

Structure of a Warm Eddy off Sogcho in May 1992 (1992년 5월 속초 근해 와동류의 구조)

  • LEE Jae Chul;MIN Dug Hong;YU Hong Sun;LEE Hyong Sun;YANG Han Soeb
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.3
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    • pp.354-363
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    • 1995
  • Temporal change of a warm eddy off Sogcho was studied using satellite infrared images from January to lune 1992 and its structure was investigated by the observations in Hay. There were two kinds of event for eddy formation. IR images in January indicated that the eddy Haying a horizontal dimension of about 200km was first formed by an injection of warm water. After some deformation and cooling processes the second restrengthening event took place in late March when a warm filament began to penetrate northward and circumvented the preexisting eddy. This eddy became a complete ring-shape with cooled water arrested inside from April to May. The maximum thickness of the isothermal subsurface layer with temperature of $10.0-10.4^{\circ}C$ was about 170m. Except that the current velocity was about 80cm/sec near the axis of the last Korea Warm Current close to Sogcho, the interior of the eddy had an anticyclonic motion with overall swirl velocity of 30-50cm/sec. Velocity rapidly decreased vertically below the main thermocline.

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Preset State of Thermoreversible Poly(vinylidene fluoride)/propylene Carbonate Gel System: 1. Core-Shell Model (열가역적인 Poly(vinylidene fluoride)/Propylene Carbonate(PC) 겔 시스템에서의 Pregea 상태 : 1. Core-Shell 모델)

  • 박일현
    • Polymer(Korea)
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    • v.26 no.2
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    • pp.227-236
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    • 2002
  • The structure of pregel state in thermoreversible poly(vinylidene fluoride)(PVDF) /propylene carbonate(PC) system was investigated by laser light scattering. It was found that the PVDF chain did not exist as a separate chain even in a very dilute concentration(i.e. 100 times more dilute than the gel formation concentration) but as a large spherical aggregate with the radius of gyration $R_G$, of 232 nm and the effective hydrodynamic radius $R_H$= of 407 nm at $40^{\circ}C$. Based upon experimental results such as $R_H/R_G$=ratio of 1.75 and the pattern of scattering intensity with a minimum, a core-shell type sphere model was suggested as a structure of the aggregate. According to this model, the radius of core part was estimated as 215 nm, the shell thickness as 192 nm, and the ratio of monomer density of the shell part to that of the core part as about 0.075.

The effect of inter-pupilary distance and accommodative convergence on binocular fusion and fixational depth (동공간 거리와 조절성 수렴이 양안 융합과 응시 깊이에 미치는 효과)

  • 반지은;감기택;정찬섭;손정영
    • Korean Journal of Cognitive Science
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    • v.14 no.1
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    • pp.17-28
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    • 2003
  • In order to provide natural images with a specified depth through three-dimensional display system, the stereo images should be similar to those projected from real environment as much as possible. Even when two persons see an identical scene, the binocular Parallax between two images of an object varies as a function of one's inter-pupilary distance (IPD). In this study, we investigated whether individual differences, such as IPD and accommodative vergence, would affect the perception of three dimensional scene provided by stereo-images. Results showed that a person's IPD is correlated with the limit of screen and binocular parallax for single vision, and affects the perceived depth of an object on fixation. More specifically, with longer IPD the limit of screen and binocular parallax for single vision is decreased, and the perceived depth is reduced. These results suggest that the screen and binocular parallax of an object should be calibrated with regard to users IPD to provide natural stereo-images with a specified depth and to Prevent double vision.

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Three cases of postpartum low back pain patients treated by heating-conduction acupuncture therapy (전열침을 적용한 산후 요통환자 치험 3례)

  • Lim, Gwang-Mook;Wi, Dae-Yong;Ko, Youn-Seok;Lee, Eun-Hee;Ban, Ji-Hye;Lee, Ah-Young
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.7 no.1
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    • pp.49-57
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    • 2012
  • Objectives : The purpose of this study is to evaluate the effect of the heating-conduction acupuncture therapy on the postpartum low back pain patients. Methods : Heating-conduction acupuncture therapy was administered three and four times on three postpartum low back pain patients. The improvement of clinical symptoms was evaluated by SF-MPQ(short form-McGill pain questionnarie), VAS(visual analogue scale) and ODI(oswestry disability index). Results : After treatment, each three patients' SF-MPQ, VAS and ODI score reduced respectively. Conclusions : Heating-conduction acupuncture therapy for postpartum low back pain patients was effective. Although this cases presented valuable result, further research is encouraged to confirm the effectiveness of this treatment.

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A Study on the Numerical Modeling Criteria for Underground Openings (지하공동굴착의 수치해석방법 적용기준 설정연구)

  • 이경진
    • The Journal of Engineering Geology
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    • v.5 no.1
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    • pp.31-44
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    • 1995
  • The puppose of this study is to propose the numerical modelling criteria for underground opening, rock mass continuum is regarded as homogeneous rock behaved linear elastic. The results of this study are summarized as follows: - Boundaries of the finite element mesh should be located at least 6 radii away from the center of the opening. - For circular openings, tension only developed when $K_0$ was less than one-fourAs the ratio of initial horiwntal to vertical stress increased, the inward springline movement increased and the inward crown movement decreased. - The displacement patterns developing for opening I shaped horse-shoe and opening II shaped powerstation are similar to those for circular openings. For both type opening I and opening II, stress concentrations develop at the intersection of the wall and floor. Greater stress concentrations are found for the type opening II.

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Paralytic Shellfish Poison of Bivalves in the Korean Waters (한국산(韓國産) 주요(主要) 이매패류(二枚貝類)의 마비성패독(痲痺性貝毒) 독화상황(毒化狀況))

  • Jeon, Joong-Kyun;Yi, Soon Kil;Huh, Hyung Tack
    • 한국해양학회지
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    • v.23 no.3
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    • pp.123-129
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    • 1988
  • The toxicity of bivalves in the Korean waters was investigated during 1987-1988. The toxicity of paralytic shellfish poison (PSP) was found in the sea mussels (Mytilus edulis galloprovincialis, M. corsucus), scallops (Patinopecten yessoensis, Chlamys farreri), tellin (Peronidia venulosa) and venus clam (Ruditapes philippinarum) among the 28 species screened. The toxicity in mussels, scallop (C. farreri) and venus clam was mainly confirmed from the samples collected around Jindong Bay in the southern coast of the peninsula, whereas the toxicities of tellin and scallop (P. yessoensis) were found in the vicinity of Pohang in the east coast. Samples from the west coast showed low levels of toxicity than those from the east arid south coasts. Although it varied with the regions, the toxicity was detected mainly during April to June, exceptionally during May to August in Pohang. The levels of toxicity were generally below the criteria of 4 mouse unit (MU)/g edible portion in foreign countries, with few exceptions.

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Effects of genistin from Vigna angularis on Lifespan-extending in Caenorhabditis elegans (팥에서 분리한 Genistin이 선충의 수명연장에 미치는 영향)

  • Lee, Eun Byeol;Ahn, Dalrae;Kim, Ban Ji;Lee, So Yeon;Cha, Youn-Soo;Kim, Mina;Song, Seuk Bo;Kim, Dae Keun
    • Korean Journal of Pharmacognosy
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    • v.46 no.1
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    • pp.17-22
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    • 2015
  • Previous phytochemical studies of Vigna angularis (Ohwi) Ohwi & Ohashi (Leguminosae) have shown the presence of saponins and flavonoids. From the seed of V. angularis, genistein-7-O-${\beta}$-D-glucopyranoside (genistin) was isolated. Lifespan-extending effect of genistin was elucidated using Caenorhabditis elegans model system. Genistin showed potent lifespan extension of worms under normal culture condition. This compound also exhibited the protective effects against thermal and oxidative stress conditions. In the case of heat stress, genistin-treated worms exhibited enhanced survival rate, compared to control worms. In addition, genistin-fed worms lived longer than control worms under oxidative stress induced by paraquat. To verify the possible mechanism of genistin-mediated increased lifespan and stress resistance of worms, we investigated whether genistin might alter superoxide dismutase (SOD), catalase activities and intracellular ROS levels. Our results showed that genistin was able to elevate SOD and catalase activities of worms and reduce intracellular ROS accumulation in a dose-dependent manner.

Uterine Cervix Metastasized from Signet Ring Cell Adenocarcinoma - 1 Case Report - (자궁경부에 전이된 반지세포암종 - 1례 보고-)

  • Kim, Tai-Jeon;Kim, Sung-Chul;Han, Kyung-Hee
    • Korean Journal of Clinical Laboratory Science
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    • v.39 no.2
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    • pp.122-127
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    • 2007
  • This study is a report about a specific patient whose primary stomach adenocarcinoma metastasized to uterine cervix adenocarcinoma. A thirty-nine year old female patient was initially diagnosed as having metastatic adenocarcinoma in the supraclavicular lymph node. Upon further examination, she was diagnosed with stomach adenocarcinoma. 8 months later, a cervix punch biopsy was performed. The stains used for examination were H&E stain, PAS stain, Alcian blue stain, Mucicarmine stain, Papanicolaou's (Pap.) stain, and as immunohistochemical stains, cytokeratin 7 and 20 were done. In the H&E stain, the tumor cells showed prominent and eccentric nuclei, thin nuclear membrane in abundant mucous cytoplasm, and cylinder shape. In the PAS stain, intracytoplasmic mucin vacuoles were stained with pink, and in Alcian blue and Mucicarmine stains, intracytoplasmic mucin vacuoles were stained with blue and red. As in the above results, she was diagnosed with undifferentiated adenocarcinoma. As found on the cytologic smear preparation of the uterine cervix stained by Papanicolaou's stains, the background was relatively clear, the number of malignant cells was relatively low, and large and eccentric nuclei in abundant cytoplasm were observed. Upon observing the tissue preparation of the uterine cervix biopsy by H&E stain, a clear background, large and eccentric nuclei, and a signet ring cell types were observed, and the number of malignant cells were fewer than in the primary uterine cervix adenocarcinoma. The vacuoles in cytoplasm were observed. The nuclear membrane and chromatin were thick and very rough, and upon observation by cytokeratin 7 and 20 of immunohistochemical stain, the tumor cells indicated a positive rate of 70% and 20%, respectively. According to these results, also she was diagnosed with metastasized uterine cervix adenocarcinoma. In summary of the results of pathologic findings on stomach biopsy and cytologic, histopathologic, and immunohistochemical finding on uterine cervix biopsy, the adenocarcinoma of her uterine cervix could assert the adenocarcinoma of signet ring cell type that was metastasized from the primary undifferentiated adenocarcinoma in stomach.

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