• 제목/요약/키워드: Vertical Changes

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공산호에서 수화발생동안 Microcystis aeruginosa 수직분포의 변동 (Diurnal Changes of Vertical Distribution of Microcystis aeruginoa during the Water Bloom in Kongsan Reservoir)

  • 문주환;김한순
    • 생태와환경
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    • 제33권2호통권90호
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    • pp.119-127
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    • 2000
  • Miceocystis aeruginosa에 의한 심한 수화가 발생한 1996년 여름동안 공산호에서 식물플랑크톤의 일수직분포와 물리.화학적 요인을 조사하였다. 최대 현존량은 M. aeruginosa가 우점으로 나타난 표층에서 나타났으며, 수심에 따라 점차 감소하였다. M. aeruginosa개체군의 높은 밀도가 이른 아침과 저녁에 표층에 축척되었으나 일몰 후에 급격히 감소하였다. 현존량의 대부분은 수심 5m 내에 분포하였고, 현존량의 일변화가 표층에서 명확하게 나타났으나 수직이동은 나타나지 않았다. 표층에서 현존량의 일변화는 바람에 의한 수평적 이동의 결과로 추측되었다.

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도시철도차량 세브론 고무 특성 변화가 진동승차감 레벨에 미치는 영향 연구 (A Study on the Effect of Changes in Chevron Rubber Characteristics on the Vibrational Ride Comfort Level of a Subway Vehicle)

  • 박남철;구정서
    • 한국기계가공학회지
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    • 제15권2호
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    • pp.57-65
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    • 2016
  • The suspension system of a subway vehicle is composed of $1^{st}$ and $2^{nd}$ springs. The suspension system is the most important parameter in determining the vibration ride comfort. If the $1^{st}$ suspension spring is designed as a spring with strong stiffness to improve the running stability at high speed, it causes vehicle vibrations. In this paper, by testing and analyzing changes of the characteristics of Chevron springs, which have been the primary suspension springs used for about 20 years, we study how changing the characteristics affects vehicle acceleration and ride comfort. The lateral and longitudinal vibrational ride comfort index levels were lower than the vertical ones. Therefore, as increasing the stiffness of Chevron springs has the greatest effect on the vertical vibrational ride comfort index level, a countermeasure for vertical vibration reduction is needed when the stiffness increases owing to aging. Finally, maintenance guidelines, including the replacement time for the Chevron rubber, were proposed based on these findings.

Cone Beam Computed Tomography의 두부계측분석을 통한 골격성 제3급 부정교합 환자에서 악교정 수술 후 입술과 주위 연조직의 수직적 변화 (The Vertical Changes of Lip and Perioral Soft Tissue Following Orthognathic Surgery in Skeletal Class III Patients by a Cephalometric Analysis of Cone Beam Computed Tomography)

  • 이종민;강주완;이종호;김창현;박재억
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제34권5호
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    • pp.311-319
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    • 2012
  • Purpose: The aim of this study is to evaluate the vertical changes of the lip and perioral soft tissue, following orthognathic surgery in skeletal class III patients by a cephalometric analysis of a cone beam computed tomography (CBCT). Methods: A total of 20 skeletal class III patients, who had bimaxillary surgery with Le Fort 1 osteotomy and bilateral sagittal split ramus osteotomy, were included in this study. The surgical plan for maxilla was posterosuperior impaction with the anterior nasal spine, as the rotation center. Further, the surgical plan for mandible was also posterosuperior movement. The soft tissue changes between lateral cephalogram and CBCT were compared. And the correlations between independent variables and dependent variables were evaluated. Results: There were no significant differences of the soft tissues changes between lateral cephalogram and CBCT. Upper lip philtrum length (SnLs), nasolabial angle increased and upper lip vermilion length (LsStms), lower lip length (StmiB'), lower lip vermilion length (StmiLi), lower lip philtrum length (LiB') and soft tissue lower facial height (SnMe') decreased after surgery. Change of SnLs (${\Delta}$SnLs) was influenced by vertical change of menton (${\Delta}$MeV), and change of LsStms (${\Delta}$LsStms) was influenced by upper lip thickness (ULT). Change of StmiLi' (${\Delta}$StmiLi') were influenced by preoperative overjet. Change of StmiB' (${\Delta}$StmiB') were influenced by preoperative overjet, vertical change of lower incisor (${\Delta}$L1V) and horizontal change of posterior nasal spine (${\Delta}$PNSH). Change of LiB' (${\Delta}$LiB') was influenced by ${\Delta}$L1V and ${\Delta}$PNSH. Change of SnMe' (${\Delta}$SnMe') was influenced by ${\Delta}$MeV, horizontal change of upper incisor (${\Delta}$U1H) and horizontal change of lower incisor (${\Delta}$L1H). ${\Delta}$Nasolabial angle was influenced by change of ULT (${\Delta}$ULT). Conclusion: Both soft tissues and hard tissues can be evaluated by CBCT. Posterosuperior rotation of maxillomandibular complex resulted in increase of upper lip philtrum length and nasolabial angle, while the upper lip vermilion length, lower lip philtrum length, lower lip vermilion length, and soft tissue lower facial height showed a decrease.

동해 중부 연안 환경 변화에 따른 명태 개체 크기 및 분포의 시공간적 변화 (Influences of Oceanographic Features on Spatial and Temporal Distributions of Size Spectrum of Walleye Pollock, Gadus chalcogrammus Inhabiting Middle Eastern Coast of Korea)

  • 정해근;이충일;박현제;박주면
    • 한국어류학회지
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    • 제32권3호
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    • pp.148-159
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    • 2020
  • 본 연구는 동해 중부 연안에 서식하는 명태의 연직 분포와 개체 크기의 계절 및 연간 변화를 분석하였다. 2016년 1월부터 2018년 2월까지 채집된 명태 개체의 전장은 16.6 cm~81.5cm 범위를 나타내었으며, 50~600 m 사이의 수심대에서 어획되었다. 이 중 25~35 cm 그룹이 차지하는 비율은 45.5%, 35~45 cm 그룹이 차지하는 비율은 27.2%를 나타내며 높은 비율을 차지하였다. 평균 전장은 1월에 가장 크고, 6월에 가장 작았으며, 6월 이후 점차 증가하는 계절주기 변동 특성을 나타내었다. 25 cm 미만 그룹은 100~200 m 수심에 서식하는 비율이 겨울철에 가장 높으며, 이후 봄, 여름, 가을에는 보다 깊은 수심으로 주 서식처를 변화하여 400 m 이상 수심에서 서식하는 비율이 40% 이상을 차지하였다. 25~35 cm와 35~45 cm 개체 그룹의 겨울철 연직 분포는 400 m 이상 수심에서 서식하는 비율이 45% 이상을 기록하였으며, 봄과 여름에는 보다 얕은 수심영역으로 서식처를 변화하여 200 m 미만 수심에서 서식하는 비율이 증가하였다. 이후 가을부터는 다시 서식하는 수심대가 깊어져 300 m 이상 수심의 비율이 증가하였다. 45 cm 이상 개체 그룹은 뚜렷한 계절 변동성을 나타내지 않으며 300 m 이상 수심에서 서식하는 비율이 가장 높았다. 이러한 명태의 연직 분포는 서식처의 물리적 환경 변화에 영향을 받는다. 특히, 상층부의 수온이 상승하고 수온약층 아래 100~300 m 수심대의 수온이 하강한 시기에는 300 m 이상의 깊은 수심대에서 어획되는 비율은 감소한 반면, 수온이 하강한 100~300 m 수심대에서 어획되는 비율이 증가하였다.

지하수 유향-유속 자료 및 균열 분포를 이용한 균열암반 특성화 기법

  • 김태희;신제현;황세호;김구영;조병욱;채병곤;김용재
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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    • pp.155-158
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    • 2004
  • To investigate the in-situ REV, cross-correlations between the ablsolute value of iu/outflux in tested boreholes and fracture frequency with various window widths were calculated. The changes of vertical flow rates can be considered as iu/outflux into/out of borehole. The results of cross-correlation analysis shows that 7m can be the most appropriate width of the appliable window.

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Vertical Distribution of Biogenic Elements and its Implication on Holocene Paleoclimatic Records in the Maxwell Bay of the South Shetland Islands, West Antarctica

  • Kim, Dong-Seon;Park, Byong-Kwon;Yoon, Ho-Il
    • Journal of the korean society of oceanography
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    • 제32권2호
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    • pp.69-74
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    • 1997
  • Depth profiles of organic carbon (C), biogenic silica (Si), and inorganic phosphorus (P) in Maxwell bay sediments were determined to investigate paleoclimatic changes during Holocene. Organic C and biogenic Si contents generally show a down-core decrease trend, which appears to be mostly controlled by their vertical fluxes through productivity in the surface waters, but it is uncertain that inorganic P contents are directly influenced by productivity changes with time. Before 4000 yr B.p. marine productivity seemed to be almost zero because ice permanently covered the surface waters of the study area. As the climate started to become relatively warm at 4000 yr B.p., ice was sporadically melted in the surface waters and thereby marine productivity gradually increased until 1500 yr B.p. For the last 1500 year, marine productivity must be high enough to overcome the dilution by high terrigenous sedimentation, thus that period was the warmest during the last 6000 year.

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일체형 입축 프로펠러수차 모형의 수력학적 성능특성 (Hydraulic Performance Characteristics of Vertical-Axis Propeller Turbine Model)

  • 박완순;이철형
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.379-382
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    • 2008
  • The propeller type hydro turbine model with vertical axis has been tested and analized. The blade angle of runner of turbine model were designed to be varied according to the condition of head and flowrate. When the changes in head and output were comparatively large, the efficiency drop were small, so the efficiency characteristics and stability of the entire operating condition were maintained in good condition. These results showed that the developed model in this study will be suitable for small hydro power stations with large changes in head and load such as sewage treatment plants and agricultural reservoirs.

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A Comparative Analysis of Body Types between Chinese and Korean Men

  • Sohn, Hee-Soon;Soon Lim;Kim, Jee-Yeon
    • The International Journal of Costume Culture
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    • 제5권3호
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    • pp.164-172
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    • 2002
  • The purpose of this study is to provide for some basic data useful to production of the apparels fit and measured well for the Chinese men. For this Purpose, Chinese adult men's body types and their changes over time which had been surveyed by preceding studies were compared by age group with those of Korean adult men which had been published in a report on National Anthropometric Survey of Korea in 1997 The results of this study can be summarized as follows; 1. As a result of comparatively analyzing the differences of body types between Chinese and Korean adult men, Chinese men have higher stature and arms, while weighing more. 2. As a result of comparatively analyzing the differences of body types between Chinese and Korean adult men by age group, it was found that the changes of body types due to aging are similar between two groups. Namely, as they become older, their vertical sizes become smaller, while their horizontal sizes become larger gradually.

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수소력발전용 입축 프로펠러 수차의 수력학적 성능특성 분석 (Hydraulic Performance of Vertical Axis Propeller Type Hydro Turbine for Small Hydropower Plants)

  • 이철형;박완순
    • 한국수소및신에너지학회논문집
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    • 제14권2호
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    • pp.171-176
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    • 2003
  • The propeller type hydro turbine model with vertical axis has been tested and analyzed. The blade angle of turbine model were designed to be varied according to the condition of head and flowrate. When the changes in head and output were comparatively large, the efficiency drop were small, so the efficiency characteristics and stability of the entire operating condition were maintained in good condition. These results showed that the developed model in this study will be suitable for small hydro power stations with large changes in head and load such as sewage treatment plants and agricultural reservoirs.

과도한 치아 마모 환자에서 수직고경 증가를 동반한 전악 수복 증례 (Full mouth rehabilitation with vertical dimension elevation in the patient with severely worn dentition: case report)

  • 이은지;신수연
    • 구강회복응용과학지
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    • 제30권4호
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    • pp.315-323
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    • 2014
  • 과도한 치아의 마모는 수직 교합 고경의 감소를 야기하여 구강 및 저작계의 병적 변화를 일으킬수 있으며, 이 경우 새로운 교합 설정과 수직 고경 회복 시 정확한 진단과 분석이 필수적이다. 이에 본 증례에서는 고딕 아치 트레이서를 통해 거상된 수직고경에서의 중심위를 기록한 후 전악 수복을 시행하였다. 본 증례는 70세 남자 환자로서 이가 시리고 아파서 음식을 먹지 못한다는 주소로 내원하였다. 전반적인 치아 마모에 의한 수직고경의 감소를 보여 면밀한 모형분석을 통해 수직고경의 거상을 결정하였다. 거상된 수직고경에 맞춰 고딕 아치 트레이서를 이용하여 중심위 채득 후 임시 보철물을 장착하였다. 4개월 동안 임시 보철물을 통해 적절한 교합을 형성하였으며 이를 이용하여 최종 보철을 제작하였다. 치료를 통해 기능적, 심미적으로 만족할 만한 결과를 얻었기에 이를 보고하는 바이다.