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Compression of Terrain Data using Integer Wavelet Transform (IWT) and Application on Gravity Terrain Correction (정수웨이블릿변환(IWT)을 이용한 지형 자료의 압축 및 정밀 지형 효과 계산을 위한 활용 방법 고찰)

  • Chung, Hojoon;Lee, Heuisoon;Oh, Seokhoon;Park, Gyesoon;Rim, Hyoungrea
    • Journal of the Korean earth science society
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    • v.34 no.1
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    • pp.69-80
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    • 2013
  • Terrain data is one of important basic data in various areas of Earth science. Recently, finer DEM data is available, which necessary to develop a method that deals with such huge data efficiently. This study was conducted on the lossless compression of DEM data and efficient partial reconstruction of terrain information from compressed data. In this study, we compressed the wavelet coefficients of DEM, obtained from integer wavelet transform (IWT) by entropy encoding. CDF (Cohen-Daubechies-Feauveau) 3.5 wavelet showed the best compression ratio of about 45.4% and the optimum decomposition level was 3. Results also showed that a small region of terrain could be restored from the inverse wavelet transform with a part of the wavelet coefficients that are related to such region instead of whole reconstruction. We discussed the potential applications of the terrain data compression for precise gravity terrain correction.

Establishment of Correspondent points and Sampling Period Needed to Estimate Object Motion Parameters (운동물체의 파라미터 추정에 필요한 대응점과 샘플링주기의 설정)

  • Jung, Nam-Chae;Moon, Yong-Sun;Park, Jong-An
    • The Journal of the Acoustical Society of Korea
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    • v.16 no.5
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    • pp.26-35
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    • 1997
  • This paper deals with establishing correspondent points of feature pints and sampling period when we estimate object motion parameters from image information of freely moving objects in space of gravity-free state. Replacing the inertial coordinate system with the camera coordinate system which is equipped within a space robot, it is investigated to be able to analyze a problem of correspond points from image information, and to obtain sequence of angular velocity $\omega$ which determine a motion of object by means of computer simulation. And if a sampling period ${\Delta}t$ is shortened, the relative errors of angular velocity are increased because the relative errors against moving distance of feature points are increased by quantization. In reverse, if a sampling period ${\Delta}t$ is lengthened too much, the relative error are likewise increased because a sampling period is long for angular velocity to be approximated, and we confirmed the precision that grows according to ascending of resolution.

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FRACTAL DIMENSION OF SIMULATED SEDIMENTS (모의류사의 쪽거리 차원)

  • 김형수;윤용남
    • Water for future
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    • v.27 no.3
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    • pp.115-121
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    • 1994
  • Cohesie sediment movement in estuarine systems is strongly affected by the phenomena of aggregation and flocculation. Aggregation is the process where primary particles are clustered together in tightly-packed formations; flocculation is the process where aggregates and single particles are bonded together to form large particle groups of very low specific density. The size, shape and strength of the flocculants control the rate of deposition and the processes of pollutant exchange between suspended sediments and ambient water. In estuarine waters, suspended sediments above the lutocline form the mobile suspension zone while below the lutocline they form the stationary suspension zone. Suspended particles in the mobile zone are generally in a dispersed state and the controlling forces are the Brownian motion and the turbulent flow fluctuations. In the stationary suspension zone, the driving force is the gravity. This paper discusses the settling and particle flocculation characteristics under quiescient flow conditions. Particles are entering the study domain randomly. Particles in the mobile suspension zone are simulated by using the Smoluchowski's model. Flocs created in the mobil suspension zone are moving into the stationary suspension zone where viscosity and drag effects are important. Utilizing the concepts of the maximum Feret's diameter and the Minkowski's sausage logic, the fractal dimension of the flocs within the stationary suspension is estimated and then compared with results obtained by other studies.

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Diagnosis and Management of Suspected Deltoid Injury (삼각인대 손상 의심 시 진단과 치료방법)

  • Yang, Sung Hun;Lee, Jun Young
    • Journal of Korean Foot and Ankle Society
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    • v.26 no.1
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    • pp.16-21
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    • 2022
  • When an ankle lateral malleolar fracture is accompanied by a deltoid ligament rupture without a medial malleolar fracture, such an injury is called a bimalleolar equivalent fracture. This means that even if there is no bony injury on the medial side, there may be functional instability of the ankle joint due to damage to the deltoid ligament. Manual or gravity external rotational stress radiography is used to differentiate an ankle bimalleolar equivalent fracture from an isolated lateral malleolar fracture. If the medial joint gap is widened on the stress radiography, the deltoid ligament injury can be diagnosed, and surgical treatment for fibula fractures is recommended. After open reduction of the fibula fracture (with syndesmotic fixation if needed), a decision on the repair of the deltoid ligament is taken depending on the surgeons' preference and intraoperative findings. The deltoid ligament repair is performed by inserting a suture anchor (or anchors) in the medial malleolus and fixing the deep and superficial deltoid ligaments to the medial malleolus. The only randomized study to evaluate the utility of deltoid ligament sutures in ankle fractures did not support the deltoid ligament suture, but the study itself had many limitations. An appropriately powered, randomized, controlled trial of the deltoid ligament repair with both patient-reported outcome and radiographic outcome evaluation is needed in the future.

Effects of Foot Bath and Spray Application of Peppermint and Grapefruit Essential Oils on Lower Extremity Edema, Pain, and Fatigue (페퍼민트, 그레이프후룻 에센셜 오일을 이용한 족욕 또는 스프레이 적용이 하지부종, 통증 및 피로에 미치는 효과)

  • Han, Ari;Kim, Juri;Hur, Myung-Haeng
    • Journal of the Korea Convergence Society
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    • v.13 no.1
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    • pp.375-386
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    • 2022
  • Work involving standing or walking for a long time can cause swelling, pain, and fatigue in the lower extremities due to the effect of gravity on the circulation of the body. This study aimed to confirm the effects of aromatherapy essential oils, as a complementary and alternative therapy, on lower extremity edema, pain, and fatigue when applied as a foot bath or spray. The study was conducted after daytime work over two consecutive days on nurses who volunteered at the E University Hospital in D Metropolitan city between 15 August 2018 and 11 October 2018. This randomized controlled study. The foot bath group received a foot bath in 9 L of water containing 0.5 ml of essential oil blended with grapefruit and peppermint in a 1:1 ratio. The spray group received the same solution in 3% dilution in the form of a spray. Edema was assessed by measuring calf and ankle circumference, while pain and fatigue were evaluated using a numerical rating scale. Data were analyzed by ANOVA and repeated-measures ANOVA. The calf circumference in the foot bath and spray groups significantly reduced compared to that in the control group (F = 14.053, p <.001) after the interventions. Lower extremity pain (F = 42.497, p < .001) and fatigue (F = 20.641, p < .001) also significantly reduced in the foot bath and spray groups compared to those in the control group after the interventions. Foot bath is recommended to relieve swelling and pain in the lower extremities, and aroma spray is highly recommended considering the ease of application.

Analysis of High School Students' Viewpoints based on Science History about Motion of Objects (과학사에 기초한 물체의 운동에 대한 고등학생들의 관점 분석)

  • Paik, Seong-Hey;Jo, Young-Jin
    • Journal of The Korean Association For Science Education
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    • v.26 no.3
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    • pp.317-329
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    • 2006
  • In this research, a questionnaire was developed to investigate high school students' viewpoints, originating from science history, on 'motion of on object', the subjects were seventy- five 10th grade students and sixty-five 11th grade students. Results found that the highest percentage among the types of 10th grade students' thoughts was related to the Middle Ages 'Impetus' viewpoints. Percentages of 11th grade students' thoughts were highest for Middle Ages and Newton views. These results provided proof that the development of student thoughts' based on science history' are consistent with school year. Furthermore, student thought regarding 'object motion' under the conditions of no force, vacuum, or air under a weightless stage were related to progressive viewpoints on science history. However, the percentage of thoughts related to earlier viewpoints were considerable. Student thoughts on parabolic motion, circle motion, and conservation amount of motion were found to be highly significant in similarity to the viewpoints of Galilei, Descartes, and Huygens; view cultivated before Newton. Consequently, this study determined that educational efficiency could be raised by providing historically more progressive views to cope with conflictory student thoughts-thoughts related to past views in science history.

Effects of Cognitive Conflicts before Confronting Anomalous Phenomena on Middle School Students' Conceptual Changes in Physics (불일치 현상 대면 전의 인지갈등이 중학생들의 물리 개념변화에 미치는 영향)

  • Kwon, Mi-Rang;Kim, Ji-Na;Kim, Jung-Bog;Kwon, Jae-Sool
    • Journal of The Korean Association For Science Education
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    • v.29 no.8
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    • pp.886-897
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    • 2009
  • One of useful strategies to change students' misconceptions into scientific conceptions in physics is the cognitive conflict strategy, the main point of which is to arouse cognitive conflicts by presenting anomalous phenomena to students. However, it has been reported that students experienced cognitive conflicts while expecting or reasoning results of an experiment before confronting an anomalous phenomenon. Therefore, we have examined how much students' cognitive conflicts were aroused before presenting an anomalous phenomenon. Then, we investigated the effects of the cognitive conflicts aroused prior to the students' confrontation with an anomalous phenomenon, both on the cognitive conflicts occurring after the students' confrontation with it, and on the students' conceptual changes. This study was performed during regular classes about light-source and weightlessness concepts. Subjects from two different middle schools in Pusan took part in the study. Preconceptions, degrees of cognitive conflicts before and after confronting anomalies, and postconceptions were checked during the classes. Then, delayed postconceptions were also checked in 3 weeks. As a result, the degree of cognitive conflicts before confronting an anomaly was as much as the degree of cognitive conflicts after it. There was significant correlation between both conflicts. Also the degree of cognitive conflicts before confronting an anomaly was a main factor in predicting the conceptual changes, while both conflicts had been related separately to the conceptual changes.

Changes in Antigenicity of Gliadin from Medium Flour by Autoclave and Microwave Treatments (가압가열 및 Microwave 처리에 의한 중력분 Gliadin의 항원성 변화)

  • Kwak, Ji-Hee;Kim, Koth-Bong-Woo-Ri;Lee, Chung-Jo;Kim, Min-Ji;Kim, Dong-Hyun;SunWoo, Chan;Jung, Seul-A;Kang, Ju-Youn;Kim, Hyun-Jee;Choi, Jung-Su;Kim, Seong-Won;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.10
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    • pp.1423-1429
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    • 2011
  • This study was conducted to evaluate the effect of physical treatments on the antigenicity of gliadin in medium wheat flour. The wheat flour was treated with an autoclave (5, 10, 30, 50 min), a microwave (1, 5, 10 min), and both (10, 30, 50 min/ 5, 10 min), and investigated by SDS-PAGE, immunoblotting and Ci-ELISA using anti-gliadin IgG. The results showed that the binding ability of anti-gliadin IgG to gliadin in wheat flour was slightly decreased when autoclaved or when autoclaved and microwaved. Especially, it was reduced to about 69% after autoclaving for 50 min and 73% after autoclaving for 50 min and microwaving for 5 min. In addition, gliadin bands in the 50 min autoclaved group disappeared in both SDS-PAGE and immunoblotting. On the other hand, the antigenicity of gliadin was unaffected by microwaving alone. Consequently, there were no considerable changes in using an autoclave alone or in combination with a microwave. These results suggest that autoclaving may affect the reduction of the antigenicity of gliadin in medium wheat flour.

Behavior of Full Scaled Geobag Retaining Wall Structure by Field Pilot Test (현장실험을 통한 식생토낭 보강토벽의 거동특성에 관한 연구)

  • Shin, Eun-Chul;Park, Kyung-Won;Shin, Hui-su;Ham, Kyung-Won
    • Journal of the Korean Geosynthetics Society
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    • v.16 no.4
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    • pp.21-31
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    • 2017
  • Geobag method is an eco-friendly method to minimize the impact on the environment in the construction of retaining wall structure as a kind of geosynthetic reinforced retaining walls. In this study, evaluated behavior of full scaled geobag retaining wall about four different types of geobag retaining walls, that is, non-compacted geobags wall, compacted geobag wall, combination of longitudinal and transversal laied geobags wall, gabion and geobag wall were constructed in the field with instrumentation. Based on the results of field measurement, transversal layered geobag wall for non-compacted case was displaced 30% more than that of mixed gabion wall. Also, the more than 2m geobag walls without reinforcement at the backfill area are turned out to be unstable in terms of wall displacement. On the one hand, the distribution of the earth pressure for all geobag retaining walls sites show within the range of Rankine's and Coulomb's earth pressure after construction. But after intensity rainfall, the transversal laied geobag walls significantly increment of soil pressure. The geobag walls which constructed in the way of mixed wall systems such as gabion and geobag, longitudinal and transversal laied geobags are much stable with comparison of transversal laied geobag wall.