• Title/Summary/Keyword: Artificial structures

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Purification of Band 3 from the Human Erythrocyte Membrane and its Incorporation into Liposome (사람 적혈구막 Band 3의 정제 및 Liposome으로의 도입)

  • Kim, Jae-Ryong;Kim, Jung-Hye;Lee, Ki-Yung
    • Journal of Yeungnam Medical Science
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    • v.3 no.1
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    • pp.41-48
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    • 1986
  • Band 3, the predominent 95,000 dalton anion transport protein, is the major intrinsic glycoprotein of the human erythrocyte membrane. This anion carrier exists as a dimer and binds the cytoskeletons such as spectrin, ankyrin and actin. And the liposomes are vesicular structures which form spontaneouly upon hydration of phospholipids. These artificial lipid vesicles have been investigated as model of the biological membranes and as a mean of improving the delivery of nucleic acids, drugs, proteins and biological substances to specific target tissues and cells. In this study, we were purified Band 3 from the human erythrocyte membrane(ghost) was prepared by hemolysis of intact human erythrocyte with weak alkali-hypotonic solution. Band 6 was removed from ghost by extracting with solution of an ionic strength of 0.15. Band 3 and Band 4 were solubilized selectively by extracting Band 6-depleted ghosts with Triton X-100 under nondenaturing conditions. Band 3 was then purified from Triton X-100 extract treated with p-chloromercuribenzoate by sucrose density gradient ultracentrifugation. This purified Band 3 was incorporated into liposomes prepared by reverse-phase evaporation. Phosphatidyl L-serine and cholesterol(1 : 1 molar ratio) were dissolved in chloroform and then chloroform was removed by rotatory evaporation under reduced pressure. Band 3 solution without Triton X-100 was introduced into a mixture of lipids and diethylether. Diethylether was subsequently removed by evaporation. This purified Band 3 and its incorporation into liposomes were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

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An Experimental Study of Sediment Transport Patterns behind Offshore Structure (외해 구조물 배후의 표사이동에 관한 실험적 연구)

  • Shin Seung-Ho;Hong Keyyong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.7 no.4
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    • pp.207-215
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    • 2004
  • Recently, securing a vast land in the land region becomes more difficult and efforts to seek its alternation in the sea area have been increased. As a consequence, the coastal region has been faced to extensive beach erosion problems. In planning offshore structures such as artificial islands, it is necessary to forecast the influence of the structure construction exerting on the beach erosion of the adjacent coast. In the present study, the sediment movement pattern behind offshore structure was examined through a series of three dimensional movable bed experiments, so as to develop the numerical model which forecasts morphological change including beach erosions. The experimental results reveal that the sediment movement patterns of the beach line side and the depth region are separated at a certain boundary line. In details, at the beach side including swash zone the sediment movement becomes dominant, which is governed by a relation between depth contours and incident wave directions, while at the depth region the bed load and suspended load due to the orbit motion of waves are carried by nearshore currents, and both movements are clearly separated at a specified boundary that is related to partial standing wave from the beach. It is expected that these results can be effectively used for verification of a numerical model on morphological change of the coast.

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Urban Area Building Reconstruction Using High Resolution SAR Image (고해상도 SAR 영상을 이용한 도심지 건물 재구성)

  • Kang, Ah-Reum;Lee, Seung-Kuk;Kim, Sang-Wan
    • Korean Journal of Remote Sensing
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    • v.29 no.4
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    • pp.361-373
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    • 2013
  • The monitoring of urban area, target detection and building reconstruction have been actively studied and investigated since high resolution X-band SAR images could be acquired by airborne and/or satellite SAR systems. This paper describes an efficient approach to reconstruct artificial structures (e.g. apartment, building and house) in urban area using high resolution X-band SAR images. Building footprint was first extracted from 1:25,000 digital topographic map and then a corner line of building was detected by an automatic detecting algorithm. With SAR amplitude images, an initial building height was calculated by the length of layover estimated using KS-test (Kolmogorov-Smirnov test) from the corner line. The interferometric SAR phases were simulated depending on SAR geometry and changable building heights ranging from -10 m to +10 m of the initial building height. With an interferogram from real SAR data set, the simulation results were compared using the method of the phase consistency. One of results can be finally defined as the reconstructed building height. The developed algorithm was applied to repeat-pass TerraSAR-X spotlight mode data set over an apartment complex in Daejeon city, Korea. The final building heights were validated against reference heights extracted from LiDAR DSM, with an RMSE (Root Mean Square Error) of about 1~2m.

Remote Control of Network-Based Modular Robot (네트웍 기반 모듈라 로봇의 원격 제어)

  • Yeom, Dong-Joo;Lee, Bo-Hee
    • Journal of Convergence for Information Technology
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    • v.8 no.5
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    • pp.77-83
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    • 2018
  • A modular robot that memorizes motion can be easily created and operated because it expresses by hand. However, since there is not enough storage space in the module to store the user-created operation, it is impossible to reuse the created operation, and when the modular robot again memorizes the operation, it changes to another operation. There is no main controller capable of operating a plurality of modular robots at the same time, and thus there is a disadvantage that the user must input directly to the modular robot. To overcome these disadvantages, a remote controller has been proposed that can be operated in the surrounding smart devices by designing web server and component based software using wired and wireless network. In the proposed method, various types of structures are created by connecting to a modular robot, and the reconstructed operation is performed again after storing, and the usefulness is confirmed by regenerating the stored operation effectively. In addition, the reliability of the downloaded trajectory data is verified by analyzing the difference between the trajectory data and the actual trajectory. In the future, the trajectory stored in the remote controller will be standardized using the artificial intelligence technique, so that the operation of the modular robot will be easily implemented.

A Study on Evaluation of Ecological Function before and after River Improvement (하천개수 전·후 하천공간의 생태기능 평가방법에 관한 연구)

  • Hong, Il;Kim, Ji-Sung;Shin, Hyoung Sub;Kim, Kyu Ho
    • Journal of Korea Water Resources Association
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    • v.47 no.4
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    • pp.397-409
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    • 2014
  • In this study, the assessment scheme has been developed to evaluate the ecological function of rivers which were changed by the river improvement project. The evaluating factors are composed of physical structure in river channels and ecological connectivity in river areas, and each value of the factors is quantified based on 4 and 2 variables, respectably. This scheme was applied to past (1918, before artificial river improvement) and present Mankyung River area. A GIS model was adopted for calculating, analysing, and presenting river ecological conditions using the 204 grids and 7 reaches in study area. Comparison results show that the evaluation grade was decreased in both factors after river improvement. The main causes of lower grade (from II to IV) for physical structure are the river straightening and crossing structures. The reduction (from II to III) in ecological connectivity grade effected by linear fragmentation due to roads and rails is found to be greater than areal fragmentation due to land-use. In particular, it is also found that a high degree of ecological connectivity in 1918 was distributed along the river, but that one in 2007 showed a tendency to scatter because of the construction of levee and increase of urbanized area.

Vegetation Characteristics of Geumnamhonam·Honam Ridge Areas Understood through Quantitative Vegetation Analysis (정량적 식생분석을 통한 금남호남·호남정맥 마루금 일대의 식생 특성)

  • Park, Seok-Gon;Kang, Hyun-Mi
    • Korean Journal of Environment and Ecology
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    • v.34 no.4
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    • pp.304-317
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    • 2020
  • This study conducted selected two sites in Geumnamhonam and four sites in Honam-Jeongmaek for vegetation survey with consideration to the location environment and anthropogenic impacts to investigate the vegetation structures of the Geumnamhonam-Jeongmaek·Honam-Jeongmaek ridge areas. Using TWINSPAN (two-way indicator species analysis), each of the two ridge areas were categorized into seven plant communities. The differential species in the TWINSPAN technique indirectly represent the environmental factors of plant communities, and the community types of the two ridge areas were divided based on environmental factors such as altitudes above sea level, soil moisture, and disturbance. These results were in harmony with the environmental factors of the DCA (detrended correspondence analysis) axis 1. In the low-lying areas of both ridge areas, afforestation tree species such as Pinus rigida and P. thunbergii were in competition with native tree species. As such, in the low-lying areas, artificial vegetation disturbance was severe due to afforestation and development projects. In relatively highland areas, such as upper slopes, and top areas, in the ridge, the vegetation type with the dominance of Quercus mongolica, Q. variabilis, and P. densiflora was preserved well. As for differences between the two ridge areas, communities dominated by Q. mongolica were distributed widely in Geumnamhonam-Jeongmaek because of the altitudes above sea level, and the latitude of this ridge area are higher than those of Honam-Jeongmaek. On the other hand, communities dominated by P. densiflora were distributed along with communities dominated by Q. mongolica, and communities dominated by Q. variabilis appeared in Honam-Jeongmaek because it is adjacent to the south coast. In quantitative vegetation analysis such as TWINSPAN and DCA, changes in species composition and the extracting environmental factors that cause the changes are important. To that end, the removal of accidental emergent species, the establishment of an investigation plan that assumes environmental factors, and the selection of the optimal analytical method suitable for the characteristics of the survey data are necessary.

A Study on Maximum Responses of Rotational Shells Subjected to Uneven Settlements by Stochastic Method (부등침하를 받는 회전 쉘의 최대응답 추정에 관한 연구)

  • 정명채
    • Computational Structural Engineering
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    • v.10 no.3
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    • pp.175-184
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    • 1997
  • The objective of this paper is to study arelationship between maximum response and its standard deviation of rotational shells that are subjected to uneven settlements. For this, the ratio, .eta, of the maximum response to standard deviation and it's approximate, .eta./sub apr/, are investigated by stochastic methods. Also, an equation for .eta./sub apr/, that is a function of predominant harmonic number is suggested. The settlements are represented by the Fourier series. Each term in the series contains two coefficients; the amplitude and the phase angle. It is assumed that phase angles are random variables and amplitudes are deterministic. To investigate the characteristics of .eta. and .eta./sub apr/, 100 phase angles for two types of artificial amplitudes spectra are used in the analysis. .eta. and .eta./sub apr/, are almost constant regardless of amplitude type, position of a shell or type of responses; they fall into from 2.0 to 2.5. .eta./sub apr/ is always close to .eta., but tends to be somewhat greater. It may be concluded that a maximum responses of rotational shells subjected to uneven settlements are .eta./sub apr/ (about 2.5) times of its standard deviation. It is considered that this result is used when we design rotational shell structures subjected to differential settlements.

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The Environmental Characteristics and Vegetation Structures of Kirengeshoma Koreana Habitats (나도승마 서식지의 환경적 특성과 식생구조)

  • Cho, Seon-Hee;Kim, Dae-Woo;Kang, Sang-Ho;Jeong, Yeo-Hong;Lee, Sung-Jae;Kim, Joon-Sun
    • Journal of Korean Society of Forest Science
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    • v.102 no.3
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    • pp.446-454
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    • 2013
  • The present study investigated the biological agents and environmental conditions of the habitats of the Kirengeshoma koreana, a class 2 endangered species class according to the South Korean Ministry of Environment (MOE), elucidated the structural characteristics of the forest stands in the habitats with the importance value and the diversity index, conducted comparative analysis of the factors, and explored their relationship with environmental factors. According to the results of direction analysis of natural habitats of the Kirengeshoma koreana, the direction was distributed to the north or the northeast, and the slope amounted to $15-40^{\circ}$, thus demonstrating that the slope has little effect. In addition, the results showed that the distribution of Kirengeshoma koreana populations dramatically increased starting in areas at least 600 m above the sea level and that the relative light intensity was 3.79% on an average. Most populations were native to gorges and crevices between rocks so that they mainly tended to inhabit areas that could see soil loss in times of precipitation. In addition, a considerable number of the populations were close to hiking trails as well, thus leading to concerns about their artificial destruction. The soil of layer a in the main growth space of the Kirengeshoma koreana was analyzed and turned out to be strongly acidic, measuring pH 4.45-4.89 (average: 4.68). All investigation sections were typical natural broad-leaved tree areas, and, judging from the fact that the Kirengeshoma koreana was most likely to appear in colonies of the Mongolian oak tree (Quercus mongolica Fisch. ex Ledeb.), the Mongolian oak tree seems to be the species of tree that has the greatest effect on the inhabitation of the Kirengeshoma koreana.

Development of Environment Friendly Permeable Concrete Bio Blocks (친환경 투수 콘크리트 바이오 블록의 개발)

  • Song, Hyeon-Woo;Lee, Joong-Woo;Kwon, Seong-min;Lee, Tae-Hyeong;Oh, Hyeong-Tak
    • Journal of Navigation and Port Research
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    • v.44 no.4
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    • pp.305-311
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    • 2020
  • Rising sea levels along the coast from global warming causes the increase of wave energy along the coast. This rise in sea levels results in relatively deep water levels, which would incur the loss of sand that had not occurred in the past from erosion in coastal areas. Generally, it has been challenging to protect against coastal erosion, and the slope, cross-sectional shape, and materials are selected for the site conditions depending on the change in external forces. However, the application of counter measures based on insufficient understanding of the phenomenon is causing various damage, indicating the need for technological development and converging technologies to improve credibility. In this study, we developed eco-friendly permeable biopolymer concrete blocks to control the coastal erosion by using the Bio-Coast, an effective porous structure that mitigates the destructive erosion caused by the rising sea levels. The hexagonal design of Bio-Coast was derived from the honeycomb, columnar joints, and clover, which are durable and stable structures in nature, and the design was changed to apply bumps on the Bio-Coast filling in the form of a clover to reduce wave overtopping and run-up. Applying the field condition of beaches on the east coast of Korea, the block weight and size were decided and the prototype blocks were manufactured and are ready for field placement. In particular, it is intended to protect coastal areas from destructive erosion by natural and artificial external forces, and to extend the design to river,s lakes, and natural walking trails, to improve the efficiency of quality control and process control through the use of blocks.

Neutral zone approach and external impression for rehabilitation of macroglossia: a case report (거대설을 가진 환자에서 중립대 개념과 연마면 인상을 이용한 총의치 수복 증례)

  • Kang, Hyeon;Seo, Nu-Ri;Park, Sang-Won;Yun, Kwi-Dug;Park, Chan;Lim, Hyun-Pil
    • Journal of Dental Rehabilitation and Applied Science
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    • v.34 no.3
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    • pp.218-224
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    • 2018
  • Macroglossia is an obstacle in regard to general prosthodontic restoration. Not only is it difficult to obtain support and stability from dentures manufactured from normal protocol, obtaining efficacy from basic mastication is also difficult. In such cases, realizing harmony between the occlusion and surrounding muscle structures may be important with regard to manufacture of stable full dentures, and it is necessary to form the appropriate polished surface for this case. The neutral zone is defined as the potential area resulting from the neuromuscular function that results in equilibrium between the outward force exerted by the tongue and the inward force exerted by the lips and cheeks. The artificial teeth of the full denture lies in this area, and if the polished zone follows the anatomic form of the dynamic muscles, the movement of the muscles simply acts as an element of stabilizing the dentures improving the esthetics through facial support.