• Title/Summary/Keyword: moving force

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Generation and Growth of Long Ocean Waves along the West Coast of Korea in March 2007 (2007년 3월 한국 서해안에 발생한 해양장파의 형성과 성장과정)

  • Choi, Byoung-Ju;Park, Yong-Woo;Kwon, Kyung-Man
    • Ocean and Polar Research
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    • v.30 no.4
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    • pp.453-466
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    • 2008
  • In order to examine the generation mechanism of long ocean waves along the west coast of Korea and to understand the amplification process of the long ocean waves, sea level, atmospheric pressure and wind data observed every minute from 2007 March 29 to 2007 April 1 were analyzed and onedimensional numerical ocean model experiments were performed. An atmospheric pressure jump propagated southeastward from Backryungdo to Yeonggwang along the west coast of Korea with speed of $13{\sim}27\;m/s$ between 2007 March 30 23:00 and 2007 April 1 1:30. Average magnitude of pressure jump was 4.2 hPa. As a moving atmospheric jump propagated from north to south along the coast, long ocean waves were generated and the sea level abnormally rose or fell at Anheung, Kunsan, Wido and Yeonggwang. Average amplitude of sea level rise (or fall) was about 113.6 cm. In a one-dimensional numerical ocean model, nonlinear shallow water equations were numerically integrated and a moving atmospheric pressure jump with traveling speed of 24 m/s was used as an external force. While the atmospheric pressure jump travels over 60 m depth ocean, a long ocean wave is generated. Because the propagation speed of the atmospheric jump is almost equal to that of the long ocean wave, Proudman resonance occurs and the long ocean wave amplifies. As the atmospheric pressure jump moves into the coastal area shallower than 60 m, the speed of the long ocean wave decreases and Proudman resonance effect decreases. However, the amplitude of the long ocean wave increases and wave length becomes shorter because of shoaling effect. When the long ocean wave hits the land boundary, amplitude of the long ocean wave drastically amplifies due to reflection. Data analysis and numerical experiments suggest that the southeastward propagation of an atmospheric pressure jump over the shallow ocean, which is a necessary condition for Proudaman resonance, generated the long ocean waves along the west coast of Korea on 2007 March 31 and the ocean waves amplified due to shoaling effect in the coastal area and reflection at the shore.

Kinematic Analysis of Deff Motion in High Bars (철봉운동 Deff 동작의 운동학적 분석)

  • Back, Jin-Ho
    • Korean Journal of Applied Biomechanics
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    • v.16 no.1
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    • pp.55-63
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    • 2006
  • The purpose of this study is to prove the kinematical characteristics of Deff motion, the high bar performance, in terms of flying phases so that we can provide basic sources for improving gymnastic performance. To do this, we selected and analyzed the performance of two athletes who did Deff motion in the high bar competition of male artistic gymnastic in the 22nd Universiade 2003 Daegu. We drew the conclusions from the kinematical factors that were came out through analyzing three-dimensional cinematography of the athletes' movements, by using a high speed video camera. To make a successful performance, a performer releases the bar at a height of a high bar vertically and at a height of 82cm horizontally, and the flying performance should be made without moving forward, as maintaining the proper balance, in order to rise over 118cm high during the flying phase. When the performer is releasing the bar, an increase of the vertical speed in the center of the body and extension of a knee joint and a hip joint contribute to increasing a flying height. And when the moving body is twisted, leaning to left side is caused by the winding movement of a knee joint, which causes an unstable bar grasp. To grasp the bar stably, just before releasing the performer should gain propulsive force from twisting rotation through increasing the speed of shoulder rotation. And before the peak point, the performer should make sure of a body rotation distance over $164^{\circ}$ so that he or she can do an aerial rotary performance smoothly. When grasping the high bar, the center of the body should be above the bar and the angle of shoulder rotation should be maintained close to $540^{\circ}$ simultaneously. he high point performance(S1) has more speed on an ascending phase and less speed on a descending phase than the low point performance (S2). At the peak point, both the rotation angle of the body and that of the shoulder in high point performance are big as well. In conclusion, it is shown that a performer can make a jump toward the high bar easily with the body straight because the performer can hold the upper part of the body erect early in a descending phase.

Kinematical Analysis of Basket with 1/2 Turn to Handstand on Parallel Bars (평행봉 Basket with 1/2 Turn to Handstand 기술 분석)

  • Back, Jin-Ho;Park, Jong-Chul;Lee, Yong-Sik
    • Korean Journal of Applied Biomechanics
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    • v.17 no.1
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    • pp.165-174
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    • 2007
  • The subject of this study was male apparatus gymnastics athlete who had scored high points doing basket with 1/2 turn on parallel bars. Then 3D motion analysis were used to calculate & analyse kinematic variables of Basket with 1/2 turn to Handstand. 1. The total average time spent for Basket with 1/2 turn took $2.16{\pm}.08sec$, at the downward upward phase took $.58{\pm}0.00sec$, $.23{\pm}.00sec$, at flight phase took $.28{\pm}.01sec$, at connected area phase took $.72{\pm}0.21sec$, at rotation area phase took $.35{\pm}.14sec$. To have a successful performance, there should be faster speed and velocity to rotate at the downward upward phase, then the upward velocity and height must be used adequately. Moreover, the speed must be faster at the flight connect phase to stabilize Center of Mass(CM) for the body, and must secure more time at the rotation area to have more stable performance. 2. After handstand on parallel bars while moving CM to right hand side, and It must be performed with big and magnificent performance with putting both hand's center to far away from the parallel bars. 3. Furthermore, CM must be moved fast from downwards to right hand side, and CM must be moved fast in vertical movement at upward and flight phase to avoid CM from moving back and forth, and left and right. 4. At downwards, the subject must rotate as bis as possible using hip-joint as wide as possible and at upwards, must put his body to vertical to have stable performance. While rotating or turning, it is better to do with bigger shoulder angle and have to make sure that trunk angle must be not scattered. To perform better and more positive in basket with 1/2 turn on parallel bars, the centrifugal force must be used big and fast at downward, and at upward and flight phase, downward movement must change to vertical movement as soon as possible while turning movement must happen at handstand position. Time spent must be shorten at connected area to stabilize CM and turning must be natural as possible while securing the necessary time of movement to well-balanced. Also, the body must be vertically closed from the ground.

Workfare in the United Kingdom : A Study on New Deal under the New Labour Government (영국의 근로연계복지에 관한 평가 : 신노동당 정부의 New Deal을 중심으로)

  • Shin, Dong-Myeon
    • Korean Journal of Social Welfare
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    • v.56 no.1
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    • pp.23-43
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    • 2004
  • The purpose of this paper is to evaluate the performance of New Deal under the New Labour government in Britain and examines the nature of New Deal with respect to workfare. The time difference of five years after the New Deal was put into effect shows that New Deal has contributed not only to include the socially excluded groups such as the young unemployed, the long-term unemployed, single parents, and the disabled into the labour market, but also to decrease the amount of income-based benefits providing for working generation. It can be said that the nature of New Deal under the New Labour is near to human capital development model rather than labour force attachment model. New Deal provides the opportunity of policy learning for the countries which pursue the reform of social security system to moving welfare beneficiaries being able to work into jobs. Policy learning can be summed up as follows. First, imposing mutual responsibility and obligations on unemployed person should be accompanied by implementing active labour market programmes of education and job training. Second, the delivery system which administrates workfare programmes should be decentralized in a local society. The cooperation between local government and enterprisers will be critical in implementing various employment programmes and moving unemployed person into jobs. Third, the case management for individual participating in workfare programme is necessary. The personal adviser should continue to provide employment services for the unemployed until he or she get a job and enter the state of self-reliance. Finally, the workfare programme should be firmly backed by the political leadership in order to overcome the oppositions of beneficiary groups under the existing social security system.

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A Study on Estimation Technique of Manoeuvring Difficulty Using the Ship Manoeuvre Simulator for Berthing/Deberthing (선박 접이안 조종 시뮬레이터를 이용한 조종위험도 평가 기법에 관한 연구)

  • Yang Seung-Yeul;Sohn Kyoung-Ho;Lee Hee-Yong;Ha Mun-Keun;Kim Hyun-Soo;Lee JIn-Ho;Im Nam-Kyun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.11a
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    • pp.81-87
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    • 2004
  • It includes the considerable concentration and dangerousness as the peculiar work of a pilot and dock-master to berthing/deberthing the big object as for the ship within the port or the ship yard. A tug utilization is getting increased in this berthing/deberthing work and the own ship is affected a lot by external force due to moving with low advance speed. In this study, we constructed the 2 dimension virtual system which can conduct the berthing/deberthing manoeuvring work by using mainly tugs in a external force, particularly strong wind. Also, propose objective standard that could estimate the degree of manoeuvring difficulty, and conducted simulation experiment for this. we analyzed correlations between the subjective estimation which is described numerically the decreased dangerousness and the objective index which is related to the main parameter regarding manoeuvring by using this simulator from the result of conducting simulation experiment. And then we discussed the estimation technique of manoeuvring difficulty.

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Biomechanical Analysisz of Varying Backpack Loads on the Lower Limb Moving during Downhill Walking (내림 경사로 보행시 배낭 무게에 따른 하지 움직임의 운동역학적 분석)

  • Chae, Woen-Sik;Lee, Haeng-Seob;Jung, Jae-Hu;Kim, Dong-Soo
    • Korean Journal of Applied Biomechanics
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    • v.25 no.2
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    • pp.191-198
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    • 2015
  • Objective : The purpose of this study was to conduct biomechanical analysis of varying backpack loads on the lower limb movements during downhill walking over $-20^{\circ}$ ramp. Method : Thirteen male university students (age: $23.5{\pm}2.1yrs$, height: $175.7{\pm}4.6cm$, weight: $651.9{\pm}55.5N$) who have no musculoskeletal disorder were recruited as the subjects. Each subject walked over $20^{\circ}$ ramp with four different backpack weights (0%, 10%, 20% and 30% of body weight) in random order at a speed of $1.0{\pm}0.1m/s$. Five digital camcorders and two force plates were used to obtain 3-d data and kinetics of the lower extremity. For each trial being analyzed, five critical instants were identified from the video recordings. Ground reaction force, loading rate, decay rate, and resultant joint moment of the ankle and the knee were determined by the inverse dynamics analysis. For each dependent variable, one-way ANOVA with repeated measures was used to determine whether there were significant differences among four different backpack weight conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results : The results of this study showed that the medio-lateral GRFs at RHC in 20% and 30% body weight were significantly greater than the corresponding value in 0% of body weight. A consistent increase in the vertical GRFs as backpack loads increased was observed. The valgus joint movement of the knee at RTO in 30% body weight was significantly greater than the corresponding values in 0% and 10% body weight. The increased valgus moment of 30% body weight observed in this phase was associated with decelerating and stabilizing effects on the knee joint. The results also showed that the extension and valgus joint moments of the knee were systematically affected by the backpack load during downhill walking. Conclusion : Since downhill walking while carrying heavy external loads in a backpack may lead to excessive knee joint moment, damage can occur to the joint structures such as joint capsule and ligaments. Therefore, excessive repetitions of downhill walking should be avoided if the lower extremity is subjected to abnormally high levels of load over an extended period of time.

'Studies on diagnosis and Treatment of tumor.abscess.ulcer in intestinal carbuncle' (장옹(腸癰)에 있어서 종양(腫瘍).농양(膿瘍).궤양(潰瘍)의 진단(診斷)과 치료(治療)에 관(關)한 고찰(考察))

  • Han, Gyu-Eon;Ryu, Bong-Ha;Park, Dong-Won;Ryu, Gi-Won;Jang, In-Gyu
    • The Journal of Internal Korean Medicine
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    • v.11 no.1
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    • pp.93-107
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    • 1990
  • Studies on diagnosis and treatment of tumor . abscess . ulcer in intestinal carbuncle were carried out. The result of studies were summerized as follows: 1. By Nai-Gyung carbuncle-tumor arose from disharmony between nutrient and defensive because of cold, abscess arose from fever victory between cold and fever, ulcer arose from decreasing function of Bi-Kam year. By latter literature Bi-Kam year could be interpreted that spleen stomach was invaded evil influence from unattainable vital force of the earth. 2. Sites of intestinal carbuncle were large intestine, small intestine, intestinal inside or outside between large and small intestine, Intestinal carbuncle was common name of a disease about large intestinal carbuncle, small intestinal carbuncle, pelvic intestinal carbuncle, shrink leg intestinal carbuncle etc.. Pain appeared Chunchu-Hyul in large intestinal carbuncle, and Gwanweon-Hyul in small intestinal carbuncle. 3. On abdominal diagnosis tumor had indistinct pain of Gwanweon Chunchu, edema and heary feeling in low abdomen, no excessive pain by hand press and intestinal boiling sound. In abscess pain descended from right side of low abdomen to huckle, and there was rejection against press, feeling about fever,water sound with flank movement. In ulcer hand approach was difficult since excessive pain diffuse to whole abdomen, and perforating ulcer sometimes caused a serious symptom of umbilical pus. 4. On fecal and urinary diagnosis in tumor urine was yellowish red pollakiuria like gonorrhoea and occasional constipation. In abscess uncomfortable rough pain short red early urine like gonorrhoea appeared during urination, and constipation with stinging pain appeared during defecation. In ulcer red rough pyuria appeared, and stinging and pain with puruloid blood appeared during defecation. 5. On treatment in tumor Daiwhang-Tang Daisenggi-Tang Dangui-Jun by dissipation method, calming down method, interior reliance maturation method, in abscess Mokdan-San Euiiin-Tang Jeokduiin-Tang by the method of water repelling pus discharge, acute breaking, in ulcer Takridanggui-Tang Paljin-Tang Bojungikki-Tang were each used by the method of interior reliance, virulence astriction, supplement vital force and blood, supplement spleen stomach. 6. On treatment patient may have to be careful of excessive moving and suprising anxiety. Abuse of acupuncture and moxibustion made patient worse, misuse of analgesics purgative intestinal irrigation etc. could provoke difficult diagnosis and perforation. So you must treat after exact diagnosis. 7. Prognosis of ease tumor ease abscess ease ulcer and ease astriction was good. If the intestinal carbuncle were not to promote to abscess and ulcer for a long time, its prognosis was bad and it could metastasize to cancer because of dark purple with hardness. So tumor abscess ulcer in intestinal carbuncle may be significant of precancerous lesion.

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Analysis of Bed Material Changes by Flushing Flow from Daecheong Dam (대청댐에서 증가방류에 의한 하상토의 변화 분석)

  • Jang, Chang-Lae;Woo, Hyo-Seop
    • Journal of Korea Water Resources Association
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    • v.42 no.10
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    • pp.845-855
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    • 2009
  • In this study, changing characteristics of bed materials downstream of Daecheong Dam by flushing flow was investigated. Flushing flow affected the downstream environment in such a way that the mean diameter of bed material was increased and the standard deviation was decreased. The vertical sorting of bed materials composed of mixed sediment in the sediment box was observed. The surface layer was composed of gravels, and uniform sand material was buried below it. Relative fractions (Di/D50) of the bed material trapped in the box was nearly 1.0 for the bed material coarser than D$_{50}$ at Hyundo gauging station, and was between two values on the bed surface before and after the flushing flow at Bugang gauging station. Ratio of driving force to resisting force for each fraction ($\tau_i^*$) with the faction size maintained constant for the bed material coarser than D$_{50}$ at Hyundo station. At Bugang station, however, it was rapidly decreased. It means that pavement of the surface layer of bed material at Bugang station was developed, with the sediment particles moving downstream uniformly by flushing flow.

DEVELOPMENT OF A PERSIMMON HARVESTING SYSTEM

  • Kim, S. M.;Park, S. J.;Kim, C. S.;Kim, M. H.;Lee, C. H.;J. Y. Rhee
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.472-479
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    • 2000
  • A persimmon harvesting vehicle that can be operated in hilly orchards as well as a manipulator that can be used to harvest persimmons located in remote positions in the trees were designed and developed. The vehicle could be operated with keeping balanced position in an inclined field and its working platform could be moved up and down easy to approach fruits in a remote region with the aids of a hydraulic and a electrical and electronics systems. The weight of the vehicle was 927 kg and the center of gravity was located at 427 mm to the inner side from the center of a right driving caterpillar, 607 mm to a rear axle from the center of a front axle, and 562 mm to upward from ground. The automatic level control sensor for leveling the working platform was activated within 14.5 ∼ 16.5 degrees of slope variation. The total length of the manipulator was 1.39 m and weight is 975 g. It was powered by a 12 V geared motor to detach persimmon fruits with a rotational force. The gripper was made of plastic and rubber to increase a frictional force. In a performance evaluation test, static tipping angle, dynamic tipping angle toward front side when the vehicle was moving downward, climbing angle, driving speed of the vehicle were measured or calculated. In persimmon harvesting tests 24.9% of yield was increased by hand picking with the aid of the vehicle and additional 7% of yield were increased when the manipulator was used. Therefore, 99010 of total possible yield was achievable when both of the vehicle and the manipulator were used for the manual persimmon harvesting. Increase in 22.5% of total yield was achieved with the manipulator only.

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Dynamic Modeling and Simulation of a Towing Rope using Multiple Finite Element Method (다물체 요소이론을 이용한 예인줄 동역학의 모델링 및 시뮬레이션)

  • Yoon, Hyeon-Kyu;Lee, Hong-Seok;Park, Jong-Kyu;Kim, Yeon-Gyu
    • Journal of Navigation and Port Research
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    • v.36 no.5
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    • pp.339-347
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    • 2012
  • After towing rope connecting a barge to a tug was subdivided into multiple finite elements, then those dynamic models was established using Newton's second law and considering the external force and moment such as tension, drag, Coriolis force, gravity, buoyancy, and impact due to free surface acting on each element. While the previous research on the model of towing rope considered only translation, five-degree-of-freedom equations of motion except roll based on the body-fixed frame were established in this paper. All elements are connected by a spring and a damper, and the stiffness of the spring was set as the equivalent value of the real rope. In order to confirm the established multiple finite element model, various scenarios such as freely falling of towing rope in the air and above the free surface, accelerating of a tug which tows a barge connected by towing rope, and sinusoidal moving of a tug were set up and simulated. As the results, the trajectories of the tug, the barge, and the towing rope showed good tendencies to the ones of real expected situations.