• 제목/요약/키워드: long arm

검색결과 307건 처리시간 0.021초

A Study on Analysis of J85 Engine V.G. Actuator Arm Shaft Crack

  • Hwang, Young-Ha;Son, Kyung-Sug;Kim, Tae-Gu
    • International Journal of Safety
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    • 제8권1호
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    • pp.6-9
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    • 2009
  • The crack in a J85 engine V.G. actuator arm shaft for a bell crank on the engine compressor was investigated. The crack was observed in twenty two shafts during the inspection of 238 shafts. The failure analysis of shaft cracks was performed by chemical composition analysis using ICP(Inductively Coupled Plasma) and by fracture surface and microstructure analysis using FE-SEM and optical microscope. The crack initiated from the top and bottom and propagated to the center along the grain boundaries. From the chemical composition analysis, the fractography of the fracture surface and the microstructure, it was found that the failure mechanism of the shafts is the inclusion-related intergranular decohesion crack. The inclusion was found out from MnS particle by EDS(Energy Dispersive Spectroscopy). The crack initiated MnS inclusion in the grain boundary and propagated with the increase of applied shear stress during long operation. In order to prevent the fracture, NDI(Nondestructive inspection) is needed periodically as recommended.

A Swing-Arm On-Machine Inspection Method for Profile Measurement of Large Optical Surface in Lapping Process

  • Sung In Kyoung;Oh Chang Jin;Lee Eung Suk;Kim Ock Hyun
    • Journal of Mechanical Science and Technology
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    • 제19권8호
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    • pp.1576-1581
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    • 2005
  • Generally, the optical components are fabricated by grinding, lapping, and polishing. And, those processes take long time to obtain such a high surface quality. Therefore, in the case of large optical component, the on-machine inspection (OMI) is essential. Because, the work piece is fragile and difficult to set up for fabricating and measuring. This paper is concerned about a swing-arm method for measuring surface profile of large optical concave mirror. The measuring accuracy and uncertainty for suggested method are studied. The experimental results show that this method is useful specially in lapping process with the accuracy of $3\~5\;{\mu}m$. Those inspection data are provided for correcting the residual figuring error in lapping or polishing processes.

Wind tunnel tests on wind loads acting on steel tubular transmission towers under skewed wind

  • YANG, Fengli;NIU, Huawei
    • Wind and Structures
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    • 제35권2호
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    • pp.93-108
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    • 2022
  • Steel tubular towers are commonly used in UHV and long crossing transmission lines. By considering effects of the model scale, the solidity ratio and the ratio of the mean width to the mean height, wind tunnel tests under different wind speeds on twenty tubular steel tower body models and twenty-six tubular steel cross-arm models were completed. Drag coefficients and shielding factors of the experimental tower body models and cross-arm models in wind directional axis for typical skewed angles were obtained. The influence of the lift forces on the skewed wind load factors of tubular steel tower bodies was evaluated. The skewed wind load factors, the wind load distribution factors in transversal and longitudinal direction were calculated for the tubular tower body models and cross-arm models, respectively. Fitting expressions for the skewed wind load factors of tubular steel bodies and cross-arms were determined through nonlinear fitting analysis. Parameters for skewed wind loads determined by wind tunnel tests were compared with the regulations in applicable standards. Suggestions on the drag coefficients, the skewed wind load factors and the wind load distribution factors were proposed for tubular steel transmission towers.

C-arm을 이용한 EVAR(Endovascular Aneurysm Repair) 시술시 Lead Curtain 설치에 따른 Staff의 피폭선량 감소에 대한 연구 (The investigation of the exposure dose reduction of the Staff according to the Lead Curtain installation in EVAR(Endovascular Aneurysm Repair) surgical operation using C-arm)

  • 유인웅;정재연;이관섭
    • 대한디지털의료영상학회논문지
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    • 제14권2호
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    • pp.33-38
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    • 2012
  • In EVAR procedure using long time C-arm, we studied exposure dose reduction and effeciency through measuring surgical staff's ESD by installing lead curtain operating table next to. The height 3 the spot (50cm, 100cm, 150cm) dose was measured on 2 locations for 600sec in the X-ray radiation considering the surgical staff's movement. To install the curtains, we compared before and after the dose. As a result, it can confirm that dose of the installation former of 50cm height and after is reduced about 75% and 91% in 2 locations. In 100cm height, the reduction of the dose was a bit confirmed. There as to dose value, measured on 150cm height the installation former and after was nearly no change. This research examined the exposure dose about the radiation of the surgical staff during EVAR procedure in which the operation time is the long time. It was implemented in the object that it reduces the radiation exposure. It could confirm the certain effect of the experimental result exposure dose reduction In EVAR procedure using long time C-arm, we studied exposure dose reduction and effeciency through measuring surgical staff's ESD by installing lead curtain operating table next to. The height 3 the spot (50cm, 100cm, 150cm) dose was measured on 2 locations for 600sec in the X-ray radiation considering the surgical staff's movement. To install the curtains, we compared before and after the dose. As a result, it can confirm that dose of the installation former of 50cm height and after is reduced about 75% and 91% in 2 locations. In 100cm height, the reduction of the dose was a bit confirmed. There as to dose value, measured on 150cm height the installation former and after was nearly no change. This research examined the exposure dose about the radiation of the surgical staff during EVAR procedure in which the operation time is the long time. It was implemented in the object that it reduces the radiation exposure. It could confirm the certain effect of the experimental result exposure dose reduction.

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상완부 및 진동형태에 관한 연구 (A Study on the Shape of the Upper Arm and the Armscye Line)

  • 김순분
    • 복식
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    • 제30권
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    • pp.201-210
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    • 1996
  • The perpose of this study is to compare and to analyze the characters of the shape of up-per arm and armscye line between young and aged women. The subjects were measured with the Mar-tin's anthropometer and with free curve ruler. 10 items in the shape of upper arm were measured and 16 items in the shape of armscye line measured indirectly based on the measured shape taken from the subjects with free curve ruler and both date were analyzed. Mean standard deviation f-test factor analysis were performed for the statistical analysis of the date. The main results were as follows: 1) The shape of the upper arm is long and narrow in youg women compared with aged. 2) The length of the axilla of the aged women were longer than that of young women. 3) There are significant differences young and aged women on the shape of armscye line. THe length of from the front point of axilla to shoulder point width and depth of the shape of the armscye line length of axilla of aged women were longer than that of young. but the length of from the back point of axilla to shoulder point of yyoung women was longer than aged. 4.) The front point of axilla was existed lower than back point of axilla in aged women while front point of axilla was existed higher than the back point in young. 5) Through the factor analysis two factors were obtained from the shape of the upper arm and five factors from the shape on armmscye line in both groups. Factor compornents in the shape of the up per arm were length width and girth of that and in the shape of the armscye line were width and length of upper and lower back and front part of the shape of the armscye line depth of the axilla. he items in the same factor were resemble each other between two groups.

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초등학교 여학생의 유방 레플리카 분석 (Analysis of breast Replicas of Elementary School Girls)

  • 이경화
    • 대한가정학회지
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    • 제37권11호
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    • pp.49-58
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    • 1999
  • This study is to develop the well-fit brassieres by observing the changes in the breast sizes and shapes, the surface area of the breast through the arm movements of 3 types (0$^{\circ}$ , 90$^{\circ}$ and 180$^{\circ}$) in vortical motion. The 11 elementary girls who are aged 12 participated in this experiment. To obtain the measures regarding the surface area of the breast, replicas are made at each motion. The results of this study are as fellows: 1. The changes in the breast sizes and shapes at each motion By increasing the motions of the arm movement, the following measure items are inclined to decrease: Shoulder length, Upper blast girth, Bust girth, Under bust girth, Upper bust depth, Bust depth, Under bust depth, Nipple to nipple breadth, Horizontal distance of bust, Horizontal length of the cup, Bust height, Cup size. By increasing the motions of the arm movement, the fellowing measure items are inclined to increase: Center point of shoulder~B.p., Shoulder point~B.p., Center point of shoulder~armpit, Upper Bust breadth, Bust breadth, Under bust breadth, Vertical distance of Bust. 2. The changes in the surface area of breast at each motion By making the replica to observe changes in the surface area, which are sectioned to 4 parts(area 1 to area 4), and volume of breast at each motion, the results are as follows: At 0$^{\circ}$and 180$^{\circ}$, the sizes of each part are ordered as the following: area2>area1>area4> area3. At 90$^{\circ}$, the sizes of each part are ordered as the following: area2>area1>area3>area4. Through these orders, it is found that the upper and inside part of the breast huts the inclination to increase so along as the motions of the arm movement increase. Also, the total surface area increases so long as the motions of the arm movement increase. As a reset of the F-test on the changes in the each surface areas, the surface area by arm movements, the significant differences among the each surface areas are found.

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Replica법을 이용한 성인 여성 유방 형태 분석에 관한 연구 (A Study on Analysis of Breast Shapes by Replica Experiments)

  • 이경화
    • 한국의류학회지
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    • 제21권4호
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    • pp.689-698
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    • 1997
  • The purpose of this study is to develop the well-fitted brassieres by observing the changes in the breast sizes and shapes, the surface area and the volume of the breast through the arm movements of 3 types (0$^{\circ}$, 90$^{\circ}$ and 180$^{\circ}$) in vertical motion. The subjects are females, who are aged twenties and wearing a brassiere size 70B, In particular, to obtain the measures regarding the surface area and the volume of the breast, replicas are made at each motion. The results of this study are as follows: 1. The changes in the breast sizes and shapes at each motion By increasing the motions of the arm movement, the following measure items are inclined to decrease: Shoulder length, Side neck point~B.P., Front neck point~B.P., Horizontal length of the cup, Upper bust circumference, Bust circumference, Upper bust depth, Bust depth, Under bust depth, Nipple to tipple breadth, Horizontal distance of bust, Bust height, Cup size. By increasing the motions of the arm movement, the following measure items are inclined to increase: Center point of shoulder~B.P., Shoulder point~B.P., Armpit~ lowest point of breast drooping, Upper bust point~B.P., B.P~Under bust point, Under bust line, Width of gap between breast, Vertical distance of Bust. 2. The changes in the surface area and volume of breast at each motion By making the replica to observe changes in the surface area, which are sectioned to 4 parts(area 1 to area 4) , and volume of breast at each motion, the results are as follows: At 0$^{\circ}$ and 90$^{\circ}$, the sizes of each part are ordered as the following: area2> areal> area4> area3. At 180$^{\circ}$, the sizes of each part are ordered as the following: areal> area2> area4> area3. Through these orders, it is found that the upper and inside part of the breast has the inclination to increase so long as the motions of the arm movement increase. Also, the total surface area increases so long as the motions of the arm movement increase. The volume of the breast increase when the surface area of the breast increases. As a result of the F-test on the changes in the each surface areas, the surface area and volume by arm movements, the significant differences among the each surface areas and the surface area are not found.

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한국산(韓國産) Abies 속(屬)의 핵학적(核學的) 유연관계(類緣關係) (Karyological Relationship of Genus Abies in Korea)

  • 김영두
    • 한국산림과학회지
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    • 제62권1호
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    • pp.60-67
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    • 1983
  • Abies 속(屬)에 있어서 한국자생종(韓國自生種)인 3종(種)과 일본(日本)에서 도입(導入)된 A. firma 등 4종(種)에 대한 유연관계(類緣關係)를 연구(硏究)하기 위하여 체염색체(體染色體)에 대한 핵형분석(核型分析)을 행(行)한 결과(結果)를 요약(要約)하면 1) 체세포(體細胞)의 염색체수(染色體數)는 4개종(個種) 공(共)히 2n=24 이고 2) 단완(短腕)의 길이의 순(順)으로 염색체(染色體)를 배치(配置)했을 때 (1), 9번(番) 염색체(染色體)의 long arm이 A. holophylla가 다른 3종(種)에 비(比)해 길어서 종식별(種識別)의 특징(特徵)이 될 수 있으며 (2), 장완(長腕) : 단완비(短腕比)(b/a)치(値)도 종(種) 식별(識別)에 유효(有效)했으며 특(特)히 그 평균치(平均値)가 A. koreana와 A. nephrolepis가 유사(類似)하고, A. holophylla와 A. firma가 유사(類似)했다. 3) Short arm 의 길이의 순(順)으로 배치(配置)했을 때 b/a치(値)의 순위(順位)는 8개(個)의 염색체(染色體)가 A. koreana와 A. nephrolepis가 같은 순위(順位)에 있고 A. holophylla와 A. firma는 2개염색체(個染色體)가 각각(各各) 유사성(類似性)이 있었다. 4) Total length의 크기의 순(順)으로 염색체(染色體)를 배치(配置)했을 때 7번(番) 및 8번(番)의 염색체(染色體)가 A. koreana와 A. nephrolepis에서 서로 유사(類似)한 특징적(特徵的)인 염색체(染色體)였다. 5) Total length의 길이 순(順)으로 배치(配置)했을 때 b/a치(値)의 순위(順位)는 A. koreana, A. nephrolepis에서 6개(個)의 염색체(染色體)가 같은 순위(順位)이고 A. holophylla와 A. firma에서는 2개(個)의 염색체(染色體)가 같은 순위(順位)에 있다. 6) Long arm의 길이의 순(順)으로 염색체(染色體)를 배치(配置)했을 때 1번(番) 염색체(染色體)가 A. koreana와 A. nephrolepis에 있어서 b/a치(値)가 큰데 비(比)하여 A. holophylla와 A. firma의 b/a치(値)는 공(共)히 작았다. 이상의 결과(結果)를 종합(綜合)하면 핵형분석결과(核型分析結果) 염색체(染色體)의 크기, Centromere를 중심(中心)으로 한 단(短), 장완(長腕)의 크기나 그 비치(比値), 또는 단완(短腕), 장완(長腕), 전장(全長)을 각각(各各) 기준(基準)으로 하여 크기 순(順)으로 배치(配置)했을 때의 특이성(特異性) 등이 종(種)의 특징(特徵)과 수종간(樹種間)의 유연성(類緣性)을 나타내는 좋은 기준(基準)이 될 수 있었다.

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식사형태와 식사능력에 따른 요양병원 여자 노인 환자의 영양섭취조사 (Nutrition Status of Elderly Female Patients in Long-term Care Hospital according to Meal Types and Eating Ability)

  • 안혜진;강주희;이홍미
    • 대한지역사회영양학회지
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    • 제19권2호
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    • pp.187-197
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    • 2014
  • Objectives: This study was carried out to determine nutritional status of elderly patients in a long-term care hospital according to meal type and eating ability. Methods: Subjects were 47 female patients aged over 65 ($79.3{\pm}7.1$ years) who resided in a long-term care hospital in Seoul. Thirty seven patients who ate diet orally were grouped according to meal type (27 general diet and 10 soft diet) and eating ability (26 eating by oneself and 11 eaten with help) and 10 were on tube feeding. Nutritional status was determined by food consumption and mid-arm circumference. Results: The mean adequacy ratios (MARs) of 12 nutrients (protein, calcium, phosphorus, zinc, vitamin A, vitamin $B_1$, vitamin $B_2$, vitamin $B_6$, niacin, folic acid, vitamin C) were 0.687 for general diet, 0.565 for soft diet, 0.680 for eating by oneself and 0.677 for eaten with help, which were significantly lower than 0.982 for tube feeding (p < 0.05 or p < 0.01). The patients on tube feeding had significantly lower % arm circumference compared to those who ate general diet (84.0% vs. 95.4%, respectively, p < 0.05). Nutrients intakes, nutrient adequacy ratio (NAR) and index of nutritional quality (INQ) were not different between meal types as well as eating ability. The most insufficiently consumed nutrients by the patients on diet were folic acid, vitamin $B_2$, and calcium (NAR 0.334~0.453, 0.515~ 0.539, and 0.516~0.533, respectively). Conclusions: The results suggested that regardless of meal type or eating ability, the subjects who were on diets in this study might have inadequate intake of folic acid as well as vitamin $B_2$, and calcium, which need to be reflected on menu planning. The measurement of mid-arm circumference presented more risk of malnutrition of patients on tube feeding than those on diets, despite apparently better nutrient consumption.

중력보상장치 기반의 근력보조 외골격 장치 (Exoskeleton Based on Counterbalance Mechanism for Arm Strength Assistance)

  • 이원범;송재복
    • 대한기계학회논문집A
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    • 제41권6호
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    • pp.469-475
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    • 2017
  • 최근 산업현장에서 작업자들의 장시간 작업으로 인한 사고 및 부상의 위험을 방지하기 위하여 작업자들의 근력을 보조할 수 있는 외골격 근력보조 장치에 대한 연구가 활발히 진행되고 있다. 그러나 기존의 외골격 장치들은 작업자의 근력을 보조하기 위하여 모터의 동력을 사용하므로, 고가일 뿐만 아니라 오작동의 위험이 있어서 산업현장에서 매우 제한적으로 사용되었다. 이러한 문제를 해결하기 위해서, 본 연구에서는 센서 및 모터 없이 순수 기계요소들만으로 구성된 근력보조 외골격 장치를 설계 및 제작하였다. 본 외골격 장치는 사람의 손목 관절을 제외한 어깨, 팔꿈치 관절의 동작이 추종 가능하며, 팔의 자중에 의한 중력토크를 상쇄 가능한 중력보상장치를 탑재하여 작업자의 팔에 대한 근력보조를 수행한다. 개발된 외골격 장치의 성능을 검증하기 위하여 EMG 센서를 이용한 근전도 비교 실험을 수행하였고, 실험 결과를 바탕으로 외골격 장치의 근력보조 성능을 확인하였다.