• 제목/요약/키워드: Flat spring

검색결과 130건 처리시간 0.022초

진해만 침매터널 상부의 수중소음의 일변화 및 음향적 특성 (Daily change and acoustical characteristics of underwater noise on a submerged sea tunnel in Jinhae Bay, Korea)

  • 신현옥
    • 수산해양기술연구
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    • 제51권3호
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    • pp.461-473
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    • 2015
  • Jinhae Bay located in the southern of Korean Peninsular is an important spawning area in Korea. By some preliminary studies it was measured several times that adult Pacific codes (Gadus microcephalus) were passed (swimming layer: 15 to 18 m) over a submerged sea tunnel (sea bottom: about 30 m) rather than another immigration route when the Pacific codes were tagged surgically with an acoustic transmitters and released inside of the Bay. There is a possibility that the Pacific codes and the other fishes use the route on the sea tunnel as an immigration route are affected by a human-generated underwater noise around the sea tunnel due to the sea tunnel traffic. On this study the 25-hour measurements of the underwater noise level by water layer were conducted with a hydrophone attached on a portable CTD and an underwater noise level meter during four seasons, and the acoustical characteristics of the underwater noise was analyzed. The mean traffic volume for one hour at the sea tunnel on the spring was shown the largest value of 1,408 [standard deviation (SD): 855] vehicles among four seasons measurement. The next one was ordered on the autumn [1,145 (SD: 764)], winter [947 (SD: 598)] and summer [931 (SD: 558)] vehicles. Small size vehicle was formed 84.3% of the traffic volume, and ultra-small size, medium size, large size and extra-large size of the vehicle were taken possession of 8.7%, 3.2%, 2.0% and 1.8%, respectively. On the daily change of the noise level in vertical during four seasons the noise level of 5 m-layer was shown the highest value of 121.2 (SD: 3.6) dB (re $1{\mu}Pa$), the next one was 10 m-layer [120.7 (SD: 3.5)], 2 m- and 15 m-layer [120.3 (SD: 3.5 to 3.7)] and 1 m-layer [119.2 (SD: 3.6)] dB (re $1{\mu}Pa$). In relation with the seasonal change of the noise level the average noise level measured during autumn was shown the highest value of 123.9 (SD: 2.6) dB (re $1{\mu}Pa$), the next was during summer [121.4 (SD: 3.2)], spring [118.0 (SD: 3.4)] and winter [116.5 (SD: 5.1)] dB (re $1{\mu}Pa$). In results of eigenray computation when the real bathymetry data (complicate shape of sea bed) was applied the average number of eigenray was 2.68 times (eigenrays: 11.03 rays) higher than those of model bathymetry (flat and slightly sloped sea bottom). When the real bathymetric data toward inside (water depth becomes shallow according to a distance between the source of noise and hydrophone) of the Bay was applied on the eigenrays calculation the number of the eigenray was 1.31 times (eigenrays: 12.49 rays) larger than the real bathymetric data toward outside (water depth becomes deep with respect to the distance). But when the model bathymetric data toward inside of the Bay was applied the number of the eigenray was 1.05 times (eigenrays: 4.21 rays) larger than the model bathymetric data toward outside.

한국 서해 경기만 연안역에서 수질환경의 시.공간적 변화 특성과 조절 요인 (Temporal-spatial Variations of Water Quality in Gyeonggi Bay, West Coast of Korea, and Their Controlling Factor)

  • 임동일;노경찬;장풍국;강선미;정회수;정래홍;이원찬
    • Ocean and Polar Research
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    • 제29권2호
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    • pp.135-153
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    • 2007
  • Temporal (seasonal) and spatial distributions and variations of various physico-chemical factors (salinity, temperature, pH, DO, COD, SPM, POC, silicate, DIP, DIN) in surface and bottom waters were studied in the coastal environment with typical macro-tidal range and monsoonal weather condition, Gyeonggi Bay, west coast of Korea. Spacial distribution patterns of these factors were generally similar to each other, and appeared to be inversely related to the distribution pattern of salinity, suggesting that water quality of the study area was primarily controlled by the physical mixing process of Han-River freshwater with nearby coastal seawater. During flooding season, silicate- and nitrogen-rich Han River water directly flowed into offshore as far as $20\sim30\;km$ from the river mouth, probably causing serious environmental problems such as eutrophication and unusual and/or noxious algal bloom, etc. Except the surface water during summer flooding season, high concentrations of nutrients appeared generally in dry season, whereas low values in spring, possibly because of the occurrence of spring phytoplankton bloom. On the other hand, nutrient flux through the estuary seems to be primarily depending on river discharge, sewage discharge and agricultural activities, especially during the rainy season. Also, nutrients in this coastal waters are considered to be supplied from the sediments of tidal-flats, which developed extensively around the Han-River mouth, especially during fall and winter of dry and low discharge seasons, possibly due to the stirring of tidal flat sediments with highly enriched pore-water nutrients by storm. And also, COD and DIN concentrations in the study area consistently increased during the last 20 years, probably because of agricultural activities and increasing discharge of industrial and domestic wastes.

주거가치에 따른 코하우징 거주의사에 관한 연구 (A Study on Intention to live in Cohousing According to Housing Value)

  • 조정현;홍서정;곽유미;곽인숙;최정신
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2006년도 추계학술발표대회 논문집
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    • pp.123-130
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    • 2006
  • This is a basic study to investigate possibility to application of cohousing model into Korea. Purpose of this study is to grasp respondents' housing value, and its influence on intention to live in cohousing. Research method used for this study was a social survey. Respondents were 214 married people residing in Seoul and its outskirts by accidential sampling. The collected data were analyzed by SPSS 12.0 program using frequency, mean, average, factor analysis, t-test, one-way ANOVA, Duncan's multiple range test, multiple regression and logit analysis. Result of this study was as follows. Housing values were classified into three categories named as individualism oriented housing value, tradition oriented housing value, and economy oriented housing value. Housing values were different by respondents groups. For example, individualism oriented housing value showed difference according to age and housing area. Tradition oriented housing value showed difference according to sex, occupation, and period of residence, while economy oriented housing value showed difference according to number of family members, housing type, and home ownership. In detail, men than women, single-income family than double-income family, and detached house resident than flat resident had higher tradition oriented housing value. The younger than the elder, and Seoul resident than outskirts resident had higher economy oriented housing value. Also home owner than tenant, and the higher tradition oriented group had stronger intention to live in cohousing than others.

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충격 감소 및 중력 보상을 위한 이족보행로봇의 무릎-골반 관절 설계 (Design of Knee-Pelvis Joint in the Biped Robot for Shock Reduction and Gravity Compensation)

  • 김영민;김용태
    • 전기학회논문지
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    • 제64권1호
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    • pp.136-142
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    • 2015
  • In the paper, a design method of knee and pelvis joint in the biped robot is proposed for shock absorption and gravity compensation. Similarly to the human's body, the knee joints of the biped robot support most body weight and get a shock from the landing motion of the foot on the floor. The torque of joint motor is also increased sharply to keep the balance of the robot. Knee and pelvis joints with the spring are designed to compensate the gravity force and reduce the contact shock of the robot. To verify the efficiency of the proposed design method, we develope a biped robot with the joint mechanism using springs. At first, we experiment with the developed robot on the static motions such as the bent-knee posture both without load and with load on the flat ground, and the balance posture on the incline plane. The current of knee joint is measured to analyze the impact force and energy consumption of the joint motors. Also, we observe the motor current of knee and pelvis joints for the walking motion of the biped robot. The current responses of joint motors show that the proposed method has an effect on shock reduction and gravity compensation, and improve the energy efficiency of walking motions for the biped robot.

의복 이미지 유형과 디자인 요소와의 관계 (A Study of Relations Between Clothes Image Types and Design Factors)

  • 유태순
    • 복식
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    • 제45권
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    • pp.103-120
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    • 1999
  • The purpose of the study is to show concretely the design features due to cltohes image after classifying the clothes image examining relations between clothes images and design factors. Samples of the study were 507 female university students. Materials of the study were 309 slide film using the spring and fall issues of magazines and catalogues in 1996 and 1997. SAS PC was used to analyze materials and finally priniciple component analysis the analysis by quantification theory 1. The results of the study were as follows. The most important images of clothes were fashion dignity activation and simplicity. In the relationship between the main image and item factor, one-piece jumper half-coat culotte skirt pantaloons and slim pants had an important effect on the fashion image while two-piece jacket, blouse, straight pants had an effect on the dignity image and three-pice, T-shirt, shirt-vest pantaloons normal pants culoote skirt and gather skirt strengthen active image. In the relationship between the main image and silhuette X-silhouette fitting upper and lower clothes upper clothes having waist line or hip bone length and mini-skirt were the factors that raisen fashion image. And in the A-, X-, Y-silhouette having normal fit upper clothes below the knee length skirt and the upper clothes below the hip line were main factors in dignity image. And H-silhouette big size sleeves mini-skirt the upper clothes below hip line were the factors that strengthened the active image. In the relationship between fashion image and detailed factors roll stand and sports collar set-in and shirt sleeves having 5-rate and long sleeves strengthened fashion image. And flat tailored collar boat and high nceckline and bow detail set-i sleeve had an important effect on the dignity image. And shirt collar boat and V-neckline shirt dolman and 7-rate sleeves were the factors that raise active image.

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플랫 타입 와이퍼 블레이드의 동적 해석을 통한 누름압 예측 (Estimation of Contact Pressure of a Flat Wiper Blade by Dynamic Analysis)

  • 김욱현;박태원;채장범;정성필;정원선
    • 대한기계학회논문집A
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    • 제34권7호
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    • pp.837-842
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    • 2010
  • 차량의 유리면에 설치된 와이퍼 시스템은 비나 눈이 올때 운전자의 시야를 확보해주는 중요한 도구이다. 블레이드는 유리면 위의 물체를 닦아내는 가장 중요한 도구이다. 와이퍼 암의 스프링이 블레이드를 유리면 위에 누를 때, 적절한 누름압이 유지되어야 최적의 성능을 얻을 수 있다. 이번 연구에서는 전체 와이퍼 시스템에 대한 동적 해석이 이루어졌다. 상용 구조 동역학 해석 프로그램인 SAMCEF를 이용하여 와이퍼 시스템의 3차원 유한 요소 모델이 생성되었다. 동적 상태에서 블레이드의 누름압의 분포가 계산되었다. 그리고 시뮬레이션 결과를 실험 결과와 비교를 하였다. 이번 연구의 결과를 이용하여 블레이드의 누름압 분포를 예측해 볼 수 있다.

한국연안에 있어서 기상 교란에 의한 해면변화 I. 태풍 빌리호(1970년)와 남 서해안의 이상고조현상 (On the Variation of Sea Level Due to Meteorological Disturbances on the Coast of Korea. I. Storm Surges Caused by Typhoon Billie, 1970, on the West and South Coasts of Korea)

  • 황진풍
    • 한국해양학회지
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    • 제6권2호
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    • pp.92-98
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    • 1971
  • 본고는 지난 12년동안 한국연안에 내습한 태풍 및 각 검조소에 출현한 매년의 최고 이상고조와 1970.8.29∼9.2에 있었던 태풍 빌리호 내습시 남 서해안의 각 검조소에서 얻은 자료에 의하여 해면변화에 대한 사례조사를 시도한 것이다. 한국연안은 매년 빈번한 기상교란 (태풍, 저기압등) 에 의하여 이상고조 또는 기상해일현상이 발생, 항만이나 연안지대에서는 적지 않은 피해를 받고 있으나 이에 관한 조사는 전혀 없었으며, 이후 연안지대의 고도이용이나 연안방재를 위하여 먼저 정확한 사례조사가 필요하다고 본다.

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순천 상내리 갯벌역에 출현하는 풀망둑(Synechogobius hasta)의 식성 (Feeding Habits of Javelin Goby Synechogobius hasta on Tide Flat in Sangnae-ri Suncheon, Korea)

  • 박종혁;정재묵;김현지;예상진;백근욱
    • 한국수산과학회지
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    • 제48권6호
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    • pp.982-987
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    • 2015
  • During the study period, a total of 158 individuals of Synechogobius hasta were collected. The range of body length (BL) was 15.4-44.5 cm. The stomachs of 26.6% of the individuals were empty. The most abundant prey was shrimp. Among shrimp, Exopalaemon orientis was the most abundant species, being present in 27% in %IRI (index of relative importance). Fishes and crabs were also abundant prey. Analysis of ontogenetic changes, suggested that shrimp were the main prey of S. hasta of two size classes (<20 and 20-25 cm). The proportion of shrimp decreased, but that of fishes and crabs increased, with increasing body length, beginning at the 25-30 cm size class. In spring, fishes were the dominant prey, while shrimps, and crabs and fishes dominated in autumn and winter, respectively.

전극 홈 형상에 따른 스캐닝 미러의 구동 특성 (Driving Characteristics of the Scanning Mirrors to the Different width and Number of the Grooves on the Electrodes)

  • 박근우;김용권
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권11호
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    • pp.575-580
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    • 2001
  • In this paper, using $500\mum-thickness\; (100)\; silicon\; wafer,\; flat\; 65\mum-thickness$ silicon mirror plates were fabricated through dry etching and wet etching, and $45\mum-depth$ grooved driving electrodes were fabricated through UV-LIGA process. Four shapes of the driving electrode were fabricated: twenty four grooves of the $50\mum-width$, twelve grooves of the $100\mum-width$, six grooves of the $200\mum-width$, and no grooves on the driving electrode. Fabricated mirror plate size and spring size are $2400\times2400\times65\mum3\; and \;500\times10\times65\mum3,$ respectively. Mirror plate parts and driving electrodes were assembled into the scanning mirrors. Measured natural resonance frequencies were about 600Hz which have error within $\pm 2%$ to calculated value. Due to the squeeze effect in the narrow gap between the mirror plate and the driving electrode, measured resonance frequencies were reduced as raising the amplitude of the mirror plate. In a case of driving electrode without grooves, the resonance frequency was reduced largely, compared with a case of driving electrode with grooves. According to the experimental results, squeeze effect was smaller in the driving electrode with smaller-width and many grooves. Therefore, the driving electrode with smaller-width and many grooves was effective in low voltage and high speed operation.

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중년여성을 위한 고부가가치 니트 조직 개발 (Development of a High Value Added Knit Structure for Middle-aged Women)

  • 이인숙;김지영
    • 패션비즈니스
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    • 제18권2호
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    • pp.148-165
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    • 2014
  • The purpose of this study is to establish a theory about the necessary structure for knitwear design, and to propose it with the practical data through the actual development of a high value added knit structure. For this study, the market was conducted along with literature reviews on the existing studies and the relevant books about knit structures. The market research aimed at the products released in the spring/summer and fall/winter seasons of 2012-2013, focusing on brand for middle aged women. The utilization of the structure by item and the characteristics of knit design were studied. The research was conducted on S/S products in May and July, and F/W products in October and December. As a result of the market research, it was shown that the lightweight structures with permeability such as plain, lace, links and links, this is repeated and rib structure were frequently utilized during the S/S season, while double structures with good shape stability were greatly utilized during the F/W season. Also, during the F/W season, a cable structure and tubular jacquard that emphasized the volume or cubic effect were frequently used, and there were many jacquard structures where a change of color sense and motive were added. Concerning the knit structures development, the researcher designed the knit structure at the actual production site of the knit fashion. A total of 5 pieces of knit structures were developed by asking a professional for programming and knitting. To the developed structures, the study added a multi-gauged effect, herringbone transformation effect, 3-dimensional surface effect, color effects, geometric patterns, lace penetration effect, and soft surface effect in a water-drop shape. In addition, the structures had differences in the added values by mixing various structures and diversely expressing color sense on the knitting line. This study proposes the direction for 21st century knitwear product design, through the development of a high value added knit structure.