• Title/Summary/Keyword: free fall

Search Result 228, Processing Time 0.026 seconds

Performance Analysis of Asymmetric Turbo Codes Using SOVA Decoding Algorithm (SOVA 복호방법을 이용한 비대칭구조 터보부호의 성능분석)

  • 신한균;강수훈;최회동;노종선
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.4A
    • /
    • pp.553-557
    • /
    • 2000
  • It is known that turbo codes have an error-floor bound according to the effective free distance at high SNR. But the performance for turbo codes in the water-fall area at low SHR has not been studied yet. In this paper, asymmetric turbo codes that consist of RSC(recursive systematic convolutional) codes with different constraint length are proposed and their performance is analysed for SOVA decoding algorithm.

  • PDF

Telematics Specific Horizontal Distance Traveled by a Falling Car

  • Shin, Seong-Yoon;Jang, Dai-Hyun;Lee, Hyun-Chang
    • Journal of information and communication convergence engineering
    • /
    • v.10 no.2
    • /
    • pp.181-186
    • /
    • 2012
  • Telematics services include automatic location tracking for emergency rescue, which is available for use in case of a car accident due to falling off roadways. This paper presents a simulation study on how far a car will fall before it hits the ground if it drops off of a roadway due to an accident or a natural disaster. The greatest horizontal distance the falling car can travel is presented in this paper, based on the assumption that air resistance as well as the direction and degree of acceleration due to gravity is negligible. This paper also presents the depth of the dent caused by the car sinking into the ground, the time it took for the car to fall free, and the velocity at which it travelled and horizontal distance it traveled. In this paper, the damage done to cars that crash into the ground and the dangers thereof are graphically represented.

The Formation and Geomorphic Development of Chon-hwang-san(Mt.) Talus (천황산 Talus의 형성과 지형발달)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
    • /
    • v.2 no.2
    • /
    • pp.173-182
    • /
    • 1996
  • The intent of this paper is to examine the talus in Chon-hwang-san in the southern part of Korean Peninsula, and then analyze its geomorphic feature and origin. The research is summarized as follows; (1) The talus is 220m long and the range of the width from 10 to 75m. The mean gradient is $33^{\circ}$ and the mean block size is $110{\times}59cm$(long axis$\times$short axis). The overall appearance of the talus is tongue-shaped and the geology of the constituent blocks is dacite. (2) This talus has two particular geomorphic landscapes. One is that the talus has not free face as source of blocks back of itself; the free face of the talus has been parallel retreated to disappearance by frost attack. The other is that the upper part of the talus is on the ridge. (3) This talus is classified into rock fall talus type, and the shape of rock fragments is angular. When considered in conjunction with face of being mentioned above, the morphology and lithology of the talus are best explained on the basis of origin under periglacial environment during late pleistocene time. (4) Most constituent rock debris are now lichen-covered, or covered with a mantle of weathering. There is no evidence of appreciable movement and for supplying block. Therefore, the talus appears to be relict or fossil form stage, currently.

  • PDF

Evaluation of Correction Parameter for the Free-fall Grab Based Mn Nodule Abundance in the Southern Sector of the KODOS (KODOS 남쪽광구에서 자유낙하식 채취기로 채취된 망간단괴 부존률 평가를 위한 보정상수 검증)

  • Lee, Hyun-Bok;Ko, Young-Tak;Kim, Jong-Uk;Chi, Sang-Bum;Kim, Won-Nyon
    • Economic and Environmental Geology
    • /
    • v.44 no.6
    • /
    • pp.475-483
    • /
    • 2011
  • Quantitative estimate of manganese nodules based on the operation of a free fall grab (FFG) needs to be corrected because of its less retrieval ability. Previously, the correction parameter of the nodule abundance collected by FFG was calculated based on the image analysis of the photos of bottom sediment in the northern sector of the nodule exploration area of Korea in the NE equatorial Pacific. However, nodules in the southern sector are commonly covered by sediment, which may prevent the use of the correction parameter estimated by photographic techniques. In this study, we attempted dual nodule sampling at the same location by different equipments (i.e. box corer (BC) and FFG) to examine the previous correction parameter of nodule abundance for FFG operation. During the exploration cruises in 2007 to 2009, Mn-nodules were collected from 40 stations both by BC and FFG in the southern sector. The correlation analysis between BC and FFG operations revealed that the BC collected nodules 1.43 times larger than FFG. Our result suggests that the correction parameter of 1.43 can be applied for collection of FFG data to estimate Mn-nodule distribution in the southern sector. The obtained parameter is similar to the previous parameter (1.42~1.45) calculated by the image analysis method, indicating an usefulness of new correction parameter suggested by this study.

Study on Suggestion a Standard Installation for Damage Reduction alarm System using Cut-Slope Data (국내 도로절개면 현황 및 붕괴 분석을 통한 경보시스템 설치 기준에 관한 기초적 연구)

  • Bae, Gyu-Jin;Koo, Ho-Bon;Baek, Yong
    • The Journal of Engineering Geology
    • /
    • v.12 no.1
    • /
    • pp.53-61
    • /
    • 2002
  • Cut-slope due to the road construction is one of the most significant problems in the domestic case, that is, 70% of the land is covered by mountain. Moreover, typhoons or heavy rains concentrated in summer season causes the failure of cut-slope. Rock-fall and soil slope failure take 40.8% and 29.5% out of the entire domestic cut-slope failure, respectively. Rock-fall is quickly occurred by the free fall or rolling of rock fragments generally in the upper slope. Soil slope failure produces a clastics-flow and increases casualty especially when caused by heave rainfall because the velocity of the movement is verb high. Considering the car speed and rock-fall velocity, it will take a life in a moment. This study analyzes a set of field data of most recently collapsed domestic road cut-slopes to characterize these cut-slopes and the nature of rock-falls and clastics flows at each site. Based on the results, design criteria for a road alarm system are proposed, considering the relationship between the time required for clastics-flow and the velocity and braking distance of a cat at the incidence. The road alarm system proposed herein would operate instantly after a rock-fall and it will minimize damages, by warning drivels approaching to the collapse or collapsing location in advance.

Geomorphic Features of ${\check{O}}rumkol$(Frozen Valley) Area (Kyungnam Province, South Korea) - Mainly about Talus - (경남 밀양 얼음골 일대의 지형적 특성 -Talus를 중심으로-)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
    • /
    • v.3 no.1
    • /
    • pp.165-182
    • /
    • 1997
  • The aim of this paper is to clarify geomorphic features on talus within ${\check{O}}rumkol$ and the origin of ${\check{O}}rumkol$. ${\check{O}}rumkol$ is located in Milyang of Kyungnam province, in South Korea. ${\check{O}}rumkol$ is good area to study talus. because it is characterized by following three geomorphic landscapes : free face surrounding ${\check{O}}rumkol$ ; ${\check{O}}rumkol$ with deep and wide valley floor ; lots of taluses typically developing within ${\check{O}}rumkol$. The main results can be summarized as follows: 1) The origin of ${\check{O}}rumkol$ may be suggested two assumptions : one is that its origin have been resulted from intrusion structure(intrusive rock might capture less resistant rock as tuff) ; the other is that its origin have been resulted from volcanic depression after intrusion or eruption. But these assumptions are not obvious. therefore more geological evidences will be supplemented after this 2) The characteristics of ${\check{O}}rumkol$ talus (1) Pattern ${\check{O}}rumkol$ taluses are tongue-shaped or cone-shaped in appearance. They are $50{\sim}200m$ in length and the range of the maximum width from 25 to 115m and one of their mean slope gradient from 32 to $36^{\circ}$ (2) Origin ${\check{O}}rumkol$ taluses have been formed under periglacial environment in the last glacial age and they are classified into rock fall talus type, considering in conjunction with the shape, hardness, sorting, weathering conditions of constituent debris. (3) The stage of landform development ${\check{O}}rumkol$ talus slope profiles are mainly concave slope. This concave slope type was eventually caused by talus creep at the lower end of the talus. That means new additions of debris from the free face have virtually ceased and there is no evidence of recent motion in the deposit. Now it is predominant that vegetation cover is gradually increasingly. Therefore ${\check{O}}rumkol$ taluses appear to be relict form stage. at present.

  • PDF

Characterization of lipophorin from hemolvmph of Fall Web-worui, Hyphantria cunea Drurv (미국휜불나방 (Hyphontrio cunea D.)의 lipophorin의 물리화학적 성질)

  • 윤화경;김학열
    • The Korean Journal of Zoology
    • /
    • v.36 no.2
    • /
    • pp.231-237
    • /
    • 1993
  • Lipophorin (LP) was purified from hemolvmph of late last instar larvae of Hyphuntria cuneo D. by KBr density gradient ultracentrifugation. Chemical composition of LP was investigated by electrophoresis, thin laver chromatography and ryas chromatography. LP consisted of Apo-LP I and Apo-LP ll, and M.W. of them were 230 Kd and 80 Nd, respectivelv. Lipid of LP was mostly composed of neutral lipid including triacylglvcerol, diacvlslvcerol, monoacylglvcerol and free cholesterol, and phospholipid rich in phosphatidvlethanolamine and phosphatidvlcholine. Fatty acids present in these lipids were found to have be 14:0, 16:0, 18:1, and 20:1.

  • PDF

SPHERICALLY SYMMETRIC ACCRETION WITH VISCOSITY (점성에 의한 구대칭 강착)

  • YOO KYE HWA
    • Publications of The Korean Astronomical Society
    • /
    • v.17 no.1
    • /
    • pp.11-14
    • /
    • 2002
  • Our examination of the relations of spherically symmetric accretion on a massive point object to viscous drag, neglecting gas pressure and using self-similar transformation, shows the behaviors of the asymptotic solutions? in the regions near to and far from the center. The viscosity reduces the free-fall velocity by the factor $(1\;+\;\zeta) ^{-1}$, and causes flattening in the density distribution. Therefore, the viscosity leads to the reduction of the mass accretion rate.

Torsional Spring Design of Big Industrial Folding-type Automatic Door to Prevent Free Fall (접이식 자동문의 자유낙하 방지를 위한 토션 스프링 장치 설계)

  • Yun, Seong-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2011.04a
    • /
    • pp.590-593
    • /
    • 2011
  • 본 논문에서는 산업용으로 널리 사용되는 접이식 자동문의 개폐 거동을 관찰하기 위한 운동방정식이 유도 되었다. 특히 자동문이 자유 낙하할 때 갑작스런 닫힘으로 인하여 작업 환경에 초래할 위험을 방지하고자 토션 스프링을 사용하였다. 설정된 작동 시간 및 속도에 적합한 토션 스프링의 강성을 산정하였고, 이를 바탕으로 스프링의 제원을 결정하였다.

  • PDF

The Reconstruction of Hand with Microsurgery (미세수술을 이용한 수부 재건술)

  • Chung, Duke-Whan;Han, Chung-Soo;Yoo, Myung-Chul;Kim, Byung-Soon;Jeun, Chul-Woo;Son, Yong-Lak
    • Archives of Reconstructive Microsurgery
    • /
    • v.1 no.1
    • /
    • pp.17-23
    • /
    • 1992
  • The authors analyzed the clinical results of the reconstructive surgery for injuried hand with microsurgery in 33 patients, 35 cases at the department of orthopaedic surgery, school of medicine, Kyung Hee university from 1985 to 1992 and the results were as followings. 1. There were 31 men and 4 women who had a mean age of 23 years(range, 3 to 44 years) and the follow up evaluations averaged 19 months. 2. The causes of the injury were machinery injury in 25 cases, traffic accident in 2, frostbite in 4, burn in 3 and fall down in 1. 3. For the reconstructive procedure, scapular free flap was applied in 6 cases, radial forearm flap in 7, dorsalis pedis free flap in 4, neurovascular island flap in 6, gracilis free flap in 1, wrap around flap in 6, toe to thumb in 5. 4. 32 cases(91.4%)were successful in reconstructive surgery with microsurgery exept the failure of scapular free flap in 2 cases and dorsalis pedis free flap in 1. 5. The causes of failure in scapular free flap were infection in 1 case and thrombosis in 1. In dorsalis pedis free flap, the cause of failure was infection. In the analysis of above results, the reconstruction with microsurgery was effective procedure for reconstruction of injuried hand.

  • PDF