• Title/Summary/Keyword: 오름

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Four unrecorded moss species from the Korean flora (한반도 미기록 선류식물 I)

  • Yoon, Young Jun;Sun, Byung-Yun
    • Korean Journal of Plant Taxonomy
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    • v.40 no.3
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    • pp.186-191
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    • 2010
  • Four unrecorded species (Barbella flagellifera, Isothecium hakkodense, Mnium orientale and Fissidens gardneri) and with one unrecorded genus, Barbella, are reported new to the Korean moss flora. B. flagellifera (Meteoriaceae) was found on a tree at alt. 300-350 m of parasitic Seogeomun-oreum Volcano on Jeju Island. The species are mainly distributed in subtropic regions. I. hakkodense (Lembophyllaceae) was found around the top of Seongin-bong on Ulleung Island. This species is similar to I. subdiversiforme, however, it can be distinguished by the morphologies of branch leaves and alar cells. M. orientale (Mniaceae) was collected from Mt. Jiri. This is similar to M. heterophyllum, however, it can be distinguished by plant size, number of teeth in leaf margin and cell size on leaf. F. gardneri (Fissidentaceae) was found along the valley of Mt. Palyeong, Jeollanam Province. This species is similar to F. obscurirete, but distinguished by the size of the plants and their leaves as well as the costal lengths of the leaves.

Application based on the strictly combined method of BEM and CADMAS-SURF (BEM-CADMAS-SURF 결합해석법에 기초한 수치조파수조의 응용)

  • Kim, Sang-Ho;Yamashiro, Masaru;Yoshida, Akinori;Shin, Seung-Ho;Hong, Key-Yong
    • Journal of Navigation and Port Research
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    • v.33 no.1
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    • pp.65-70
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    • 2009
  • The hybrid numerical model is developed by combining BEM that can calculate the wave motion rapidly under the potential theory and CADMAS-SURF that solves Navier-Stokes equations for the free surface variation near the structure, In the hybrid model the calculation of wave motion in a wide field of wave reflection for deep water area is conducted by BEM but for shallow water area by CADMAS-SURF. Especially the hybrid model can calculate random wave motions for long term period more rapidly with almost similar accuracy than the calculation of wave motion which was carried out by CADMAS-SURF only. In this study the coupling model was applied to the calculation of the strong nonlinear wave motion such as wave runup and overtopping at the coastal structure on the mild-slope bottom and the results of numerical model were compared with the Toyosima's experiments of regular wave runup and Goda's design diagram of ramdom wave overtopping, respectively.

Numerical modeling of impulse wave (수면 충격파의 수치모의)

  • Paik, Joongcheol
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.44-44
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    • 2015
  • 저수지나 하천 사면에서 발생하는 산사태와 토석류는 저수지와 하천 수체에 충격을 가한다. 이로 인해 발생하는 수면 충격파는 전파되어 반대편 제방으로 파의 처오름 또는 댐 제체위로의 물넘이로 큰 피해를 줄 수 있다. 최근 외국에서는 2차원 충격파 생성 및 전파의 기본 과정을 구명하기 위한 실험적 연구가 이뤄지고 있으며, 이들 연구들은 충격파의 발생과 전파, 사면활동 물질과 수체의 상호작용 그리고 자유 수면과 유속분표의 발달에 대한 자세한 관측 자료를 제시하고 있다. 아울러 충격파에 영향을 주는 지배 매개변수를 제시하고 있다. 하지만, 이러한 실험적 연구의 최근 진보에도 불구하고, 이들 지배 매개변수를 고려한 충격파 지배공식들은 대상 지역의 복잡한 바닥 지형이나, 평면적 지형 변화를 단순한 추정치로만 고려하게 된다. 따라서 복잡한 지형조건에서 토석류와 수체의 상호작용과 수면 충격파의 전파를 합리적으로 해석하는 데는 한계가 있다. 이 경우 수치모델링 기법을 대안으로 적용할 수 있으나, 수치모델링은 수면에서 충격파의 전파와 수중에서 토석류의 전파를 동시에 모의해야 하고, 뉴턴 유체와 비뉴턴 유체의 특성을 동시에 고려해야하므로 수치해석 연구자들에게는 하나의 큰 도전사항이다. 이 연구는 경계면 포착기법을 이용한 계산유체동력학 기법을 이용하여 사면활동과 이로 인한 정지 수역에서의 충격파의 발생 및 전파를 재현하기 위한 수치 모델링 기법을 개발하는 것이 목적이다. 사면활동과 수면의 경계면을 포착하고 위치를 정립하기 위해서 VOF (volume of fluid) 경계면 재구축 기법을 이용한다. 지배 방정식은 비압축성(incompressible) 질량 보존방정식과 나비어-스톡스(Navier-Stokes) 방정식이며, 서로 다른 유체의 상(phase)애 대한 체적분할이송방정식을 이용한다. 큰와 모의 계열의 난류 모델링 기법을 적용하여 충격파의 전파와 붕괴에 대한 난류의 영향을 고려하였다. 토석류는 비뉴턴 흐름저항 관계식을 적용하여 그 흐름특성을 재현하였다. 이들 지배방정식은 2차 정확도의 유한체적법(finite volume method)을 이용하여 해석한다. 외국의 연구자들이 관측하여 제시한 길이 11 m 그리고 폭 0.5 m의 수로에서 발생한 충격파를 수치적으로 재현하여 개발된 모형의 실제 문제에 대한 적용성을 보여준다.

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Flow regime analysis method by using discharge Gini coefficient (유량 지니계수를 이용한 유황분석방안)

  • Park, Tae Sun
    • Journal of Korea Water Resources Association
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    • v.54 no.12
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    • pp.1223-1232
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    • 2021
  • In this study, a new analysis method by using a "Discharge Gini Coefficient" is presented to determine the degree of inequality in daily discharge throughout the year. The Discharge Gini Coefficient can be calculated using the area relationship with the cumulative percentage of the daily mode discharge in the ascending order according to the cumulative percentage of the date of occurrence of the daily discharge throughout the year. The Discharge Gini Coefficient is presented as a value between 0 and 1, and the degree of inequality can be divided into 5 levels. The Discharge Gini Coefficient can be used to estimate the discharge stability of the downstream point relative to the upstream point. In addition, it is possible to quantify the influence of each reference discharge on the total inequality. The applicability of the Discharge Gini Coefficient was reviewed using long-term daily discharge data at eight points upstream and downstream of the four major rivers in Korea. The Discharge Gini Coefficient can also be used to analyze the discharge control effect in the downstream by the upstream dam.

Characteristics of Wave by Additional Installation of Porous Dual Circular Caissons on the Existing Breakwater (기존 방파제에 투과성 이중 원형케이슨 추가설치에 따른 파랑 특성 분석)

  • Park, Min Su
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.6
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    • pp.396-410
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    • 2020
  • The design and the construction are carried out by installation of new caissons on the back or the front of existing caissons to increase the stability of existing caisson breakwater. In this study, we use the eigenfunction expansion method to analyze the effects of wave structure interaction when new porous dual circular caissons are installed on the back or the front of existing breakwater. The porous dual circular caisson which consisting of a porous outer cylinder circumscribing an impermeable inner cylinder is one type of seawater exchanging breakwater. The comparison of numerical results between present method and Sankarbabu et al. is made, and the wave force and the wave run-up acting on each porous dual circular caisson are calculated for various parameters by considering the wave structure interaction.

A Study on the Locality Implied in the Architecture of Jeju IT Companies (제주 IT기업의 건축에 내포된 지역성에 관한 연구)

  • Kim, Hyoungjun
    • Journal of Industrial Convergence
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    • v.20 no.7
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    • pp.73-78
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    • 2022
  • This paper is a study on locality in architecture in Jeju with the theme of locality of architecture. This paper, as the last research paper in this series of studies, is a paper that verifies whether there is anything other than the locality revealed in the categories of 'hermeneutic' and 'phenomenal'. To this end, in this paper, the regional characteristics of the buildings of five Jeju IT companies were analyzed. As a result, the elements reflected in the architecture in terms of the locality of Jeju were quite insufficient. This can be seen as a result of the fact that the corporate image is important in terms of the architecture of an IT company. Nevertheless, if we summarize the elements that reflect the characteristics of Jeju in IT architecture, it is the wind and oreum used as architectural concepts, and Jeju stone used as the exterior finish. In conclusion, it could be seen that the regional characteristics of wind, oreum, and Jeju stone were used in IT architecture, and it was also found that these characteristics were within the scope of interpretive locality and phenomenal locality. Soon, it was found that the locality of Jeju architecture was within the hermeneutic and phenomenal category.

Real-time Wave Overtopping Detection and Measuring Wave Run-up Heights Based on Convolutional Neural Networks (CNN) (합성곱 신경망(CNN) 기반 실시간 월파 감지 및 처오름 높이 산정)

  • Seong, Bo-Ram;Cho, Wan-Hee;Moon, Jong-Yoon;Lee, Kwang-Ho
    • Journal of Navigation and Port Research
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    • v.46 no.3
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    • pp.243-250
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    • 2022
  • The purpose of this study was to propose technology to detect the wave in the image in real-time, and calculate the height of the wave-overtopping through image analysis using artificial intelligence. It was confirmed that the proposed wave overtopping detection system proposed in this study could detect the occurring of wave overtopping, even in severe weather and at night in real-time. In particular, a filtering algorithm for determining if the wave overtopping event was used, to improve the accuracy of detecting the occurrence of wave overtopping, based on a convolutional neural networks to catch the wave overtopping in CCTV images in real-time. As a result, the accuracy of the wave overtopping detection through AP50 was reviewed as 59.6%, and the speed of the overtaking detection model was 70fps based on GPU, confirming that accuracy and speed are suitable for real-time wave overtopping detection.

Numerical Simulation on Reduced Runup Height of Solitary Wave by Fixed Submerged and Floating Rectangular Obstacles (고정된 사각형 수중 및 부유식 구조물에 의한 고립파의 처오름높이 저감 수치모의)

  • Choong Hun, Shin;Hyung Suk, Kim
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.34 no.6
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    • pp.211-221
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    • 2022
  • The wave runup height is one of the most important parameters for affecting the design of coastal structures such as dikes, revetments, and breakwaters. In this study, SWASH (Zijlema et al., 2011), a non-hydrostatic pressure numerical model, was used to analyze the effect of reducing The wave runup height of solitary waves by submerged and floating rectangular obstacles. It was confirmed that the SWASH model reproduces the propagation, breaking, and runup of solitary waves quite well. In addition, it was confirmed that the wave deformation of the solitary wave by submerged and floating rectangular obstacles was well reproduced. Finally, we conducted an examination of the effect of reducing the runup height of submerged and floating rectangular obstacles. Reduced runup heights are calculated and the characteristics of runup height reduction according to the dimensions of the obstacle were analyzed. The energy attenuation effect of the floating obstacle is greater than the submerged obstacle, and it is shown to be more effective in reducing the runup height.

Effect of Pediatric Integrative Manual Therapy, a Novel Mobilization with Facilitation Movement Technique, on Congenital Muscular Torticollis after Cervical Rotation and Head angle: A Case Report (선천성 근성 사경에 대한 새로운 촉진 기법을 이용한 소아 통합 도수치료적용 후 경추각도의 변화와 머리각도 변화: 단일사례연구)

  • Seung-hyoek Song;Gue-jung Hwang;Tae-gyu Seo;Jae-deung Kim;Won-jeong Whang
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.29 no.2
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    • pp.77-91
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    • 2023
  • Background: Congenital muscular torticollis results in reduced head mobility, such as cervical rotation, due to the abnormal size and contraction of the sternocleidomastoid muscle. Korea Pediatric integrative manual therapy and stretching are recommended to improve head rotation upper cervical spine mobility. Therefore, in this study, the effect of the new PIMT was investigated. Methods: The patient is a 3.5 month-old diagnosed with congenital muscular torticollis (CMT). Due to the limitation of head rotation and cervical spine rotation and flexion mobility, the child visited a rehabilitation center and after diagnosis, Pediatric integrative manual therapy (PIMT) treatment was performed five times a week for a total of 15 weeks. The child's head rotation and flexion limitation and plagiocephaly were evaluated. Results: In conclusion, this study shows that compared to other treatments, PIMT approach is a more effective treatment for improving head rotation and cervical limitation for range of motion in CMT infants. Conclusion: PIMT approach was effective in improving cervical rotation and Head lateral flexion mobility and plagiocephaly in CMT patients.

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Effect of Beach Curvature on Wave Fields in Coastal Area with Submerged Breakwaters (잠제 설치 연안역의 파동장에 미치는 해안곡률의 영향)

  • Hur, Dong-Soo;Lee, Woo-Dong;Yeom, Gyeong-Seon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.463-472
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    • 2009
  • The aim of this study is to examine the effect of beach curvature on wave fields in coastal area with Submerged Breakwaters using the 3D numerical model that is able to simulate directly interaction of WAve Structure Sandy beach (LES-WASS-3D). At first, the adopted model was validated through the comparison with an existing experimental data and showed fairly nice agreement. And then, the numerical simulations have been performed to investigate the effect of according to the variation of beach curvature. Based on the numerical results, the wave height, mean surface elevation, mean flow around submerged breakwaters and longshore distributions of run-up height have been discussed in relation to the variation of beach curvature.