• 제목/요약/키워드: Time-scale

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배추흰나비(Pieris rapae L.) 날개의 인편(鱗片)과 소켓트의 형성(形成)에 관한 미세구조(微細構造) (Ultrastructure on the Forming of the Scale and Socket in the Wing of the Pieris rapae L.)

  • 강성훈;김창식;김우갑
    • Applied Microscopy
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    • 제19권2호
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    • pp.27-42
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    • 1989
  • The forming process of scale and socket of Pieris rapae L. during in 30 hr. pupa to in adult was morphologically investigated with scanning electron microscopy and transmission electron microscopy. 1. The scale forming cells which were distinguished from other epidermal cells were first observed in 30 hr. pupa. In the aspect that scale forming cell beared some morphological relations to socket forming cells and in the distribution of its organelles, scale forming cell was divided into three regions-basal region in which nucleus located, neck region which was surrounded by socket forming cells and scale region that was the cytoplasmic projection region over the wing surface. In process of the development of scale forming cell neck region and scale region were extended into the molting space and at this time, the changes of surface structure of scale region have occurred initially. 2. There was a more distinct process that scale region changed into the scale. Scale region which was first originated as clublike projection of the cell body was subsequently elongated and flattened out by broadening of the cytoplasm. After that, in the surface of scale were formed longitudinal ridges and microribs. In the late pupa, the cytoplsam of scale region have autolyzed by lysosome-like bodies and at length, scale which had air spaces, trabecula, pigment granules, longitudinal ridges and transverse ridges. 3. The major protion of socket forming cell located beside neck region of scale forming cell under the wing surface but the processing portion of the cell lay over the wing surface, suggesting that socket forming cells have actively processing. In extending to the molting space of neck and scale region, socket forming cells developed to the molting space and constructed socket.

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Nano-Scale MOSFET의 게이트길이 종속 차단주파수 추출 (Gate-Length Dependent Cutoff Frequency Extraction for Nano-Scale MOSFET)

  • 김종혁;이용택;최문성;구자남;이성현
    • 대한전자공학회논문지SD
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    • 제42권12호
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    • pp.1-8
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    • 2005
  • 본 연구에서는 측정된 S-파라미터로부터 추출된 Nano-scale MOSFET 등가회로 파라미터의 scaling 방정식을 사용하여 차단주파수의 게이트 길이 종속성을 모델화하였다. 모델된 차단주파수는 게이트 길이가 줄어듬에 따라서 크게 증가하다가, 점점 증가율이 크게 감소하는 경향을 보였다. 이는 게이트 길이가 감소함에 따라 내부전달시간은 크게 줄어들지만, 외부 기생 충전시간은 상대적으로 조금씩 감소하기 때문이다. 이와 같은 새로운 게이트길이 종속 모델은 Nano-scale MOSFET의 RF성능을 최적화시키는 데 큰 도움이 될 것이다.

Comparison between wind load by wind tunnel test and in-site measurement of long-span spatial structure

  • Liu, Hui;Qu, Wei-Lian;Li, Qiu-Sheng
    • Wind and Structures
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    • 제14권4호
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    • pp.301-319
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    • 2011
  • The full-scale measurements are compared with the wind tunnel test results for the long-span roof latticed spatial structure of Shenzhen Citizen Center. A direct comparison of model testing results to full-scale measurements is always desirable, not only in validating the experimental data and methods but also in providing better understanding of the physics such as Reynolds numbers and scale effects. Since the quantity and location of full-scale measurements points are different from those of the wind tunnel tests taps, the weighted proper orthogonal decomposition technique is applied to the wind pressure data obtained from the wind tunnel tests to generate a time history of wind load vector, then loads acted on all the internal nodes are obtained by interpolation technique. The nodal mean wind pressure coefficients, root-mean-square of wind pressure coefficients and wind pressure power spectrum are also calculated. The time and frequency domain characteristics of full-scale measurements wind load are analyzed based on filtered data-acquisitions. In the analysis, special attention is paid to the distributions of the mean wind pressure coefficients of center part of Shenzhen Citizen Center long-span roof spatial latticed structure. Furthermore, a brief discussion about difference between the wind pressure power spectrum from the wind tunnel experiments and that from the full-scale in-site measurements is compared. The result is important fundament of wind-induced dynamic response of long-span spatial latticed structures.

Investigations on aerosols transport over micro- and macro-scale settings of West Africa

  • Emetere, Moses Eterigho
    • Environmental Engineering Research
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    • 제22권1호
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    • pp.75-86
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    • 2017
  • The aerosol content dynamics in a virtual system were investigated. The outcome was extended to monitor the mean concentration diffusion of aerosols in a predefined macro and micro scale. The data set used were wind data set from the automatic weather station; satellite data set from Total Ozone Mapping Spectrometer aerosol index and multi-angle imaging spectroradiometer; ground data set from Aerosol robotic network. The maximum speed of the macro scale (West Africa) was less than 4.4 m/s. This low speed enables the pollutants to acquire maximum range of about 15 km. The heterogeneous nature of aerosols layer in the West African atmosphere creates strange transport pattern caused by multiple refractivity. It is believed that the multiple refractive concepts inhibit aerosol optical depth data retrieval. It was also discovered that the build-up of the purported strange transport pattern with time has enormous potential to influence higher degrees of climatic change in the long term. Even when the African Easterly Jet drives the aerosols layer at about 10 m/s, the interacting layers of aerosols are compelled to mitigate its speed to about 4.2 m/s (macro scale level) and boost its speed to 30 m/s on the micro scale level. Mean concentration diffusion of aerosols was higher in the micro scale than the macro scale level. The minimum aerosol content dynamics for non-decaying, logarithmic decay and exponential decay particulates dispersion is given as 4, 1.4 and 0 respectively.

한국형 공유 의료적 의사 결정 측정도구 개발 및 평가 (Development and Evaluation of Shared Medical Decision-Making Scale for End-of-Life Patients in Korea)

  • 조계화
    • 대한간호학회지
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    • 제42권4호
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    • pp.453-465
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    • 2012
  • Purpose: The study was done to develop a shared decision-making scale for end-of-life patients in Korea. Methods: The process included construction of a conceptual framework, generation of initial items, verification of content validity, selection of secondary items, preliminary study, and extraction of final items. The participants were 388 adults who lived in one of 3 Korean metropolitan cities: Seoul, Daegu, or Busan. Item analysis, factor analysis, criterion related validity, and internal consistency were used to analyze the data. Data collection was done from July to October 2011. Results: Thirty-four items were selected for the final scale, and categorized into 7 factors explaining 61.9% of the total variance. The factors were labeled as sharing information (9 items), constructing system (7 items), explanation as a duty (5 items), autonomy (4 items), capturing time (3 items), participation of family (3 items), and human respect (3 items). The scores for the scale were significantly correlated among shared decision-making scale, terminating life support scale, and dignified dying scale. Cronbach's alpha coefficient for the 34 items was .94. Conclusion: The above findings indicate that the shared decision-making scale has a good validity and reliability when used for end-of-life patients in Korea.

중유화력발전소 탈황 흡수탑 세정시기예측 (Estimation of Washing Duration of Desulfurized Absorber in a Heavy Oil Power Plant)

  • 장영기;유호선
    • 플랜트 저널
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    • 제12권1호
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    • pp.24-28
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    • 2016
  • 중유를 연소하는 D 발전소 탈황설비는 운전시간의 경과에 따라 흡수탑 내부에 석고 스케일이 부착되어 발전가능 최대출력의 하향조정이 발생되고 나아가 발전정지를 초래한다. 스케일 제거를 위한 탈황설비 세정은 발전가능 최대출력의 하향조정이 발생하는 시점으로 결정할 수 있다. 본 연구에서는 탈황설비의 운전 자료를 분석하여 발전가능 최대출력의 하향조정이 발생되기 6주전은 탈황설비 출구 $SO_2$ 농도값이 130ppm을 초과하고 동시에 흡수탑 차압은 $380mmH_2O$을 초과하며, 직전 흡수탑 세정 이후 44주가 경과된 시점이 됨을 확인하였다. 최종적으로 흡수탑의 세정시기는 직전 세정시점으로부터 50주가 경과된 시점임을 예측하였다.

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시간사용중재가 뇌졸중 환자의 생활만족도 및 자아존중감에 미치는 영향 (Effects of Time-Use Intervention on Life Satisfaction and Self-Esteem in Stroke Patients)

  • 류성현;박수진;김민혁;황도연
    • 재활치료과학
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    • 제9권3호
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    • pp.91-102
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    • 2020
  • 목적 : 본 연구는 뇌졸중 환자를 대상으로 8주간 실시된 시간사용중재가 뇌졸중 환자의 생활만족도 및 자아존중감에 미치는 영향을 알아보았다. 연구방법 : 본 연구는 2019년 7월부터 10월까지 뇌졸중 환자 21명을 대상으로 실험군과 대조군으로 나누어 실시하였다. 생활만족도의 변화는 생활만족도 척도(Life satisfaction scale)를 사용하였고, 자아존중감의 변화는 자아존중감 척도(Self-esteem scale)를 사용하였다. 결과 : 첫째, 실험군과 대조군 각각 중재 전과 후를 비교한 결과, 생활만족도와 자아존중감 모두 통계학적으로 유의한 차이를 보였다(p<.05). 둘째, 중재 후 실험군과 대조군의 생활만족도와 자아존중감을 비교한 결과, 통계학적으로 두 집단 간 유의한 차이를 보였다(p<.05). 결론 : 본 연구의 결과 시간사용중재가 뇌졸중환자의 생활만족도와 자아존중감에 긍정적인 영향을 미쳤으며, 따라서 의미있는 작업 수행의 참여가 뇌졸중 환자의 정신건강과 생활의 질을 향상시킬 수 있을 것이다.

자중계를 활용한 건설폐기물 수집·운반 차량의 과적 예방효과 연구 (A Study on the Overload Prevention Effect of Construction Waste Collection and Transportation Vehicles Using On-Board Truck Scale)

  • 김종우;정영우
    • 한국건설순환자원학회논문집
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    • 제8권4호
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    • pp.444-449
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    • 2020
  • 본 연구에서는 건설폐기물의 발생에서부터 수집·운반 및 중간처리 또는 최종처리까지의 모든 단계에서의 폐기물의 중량을 모니터링 하기 위하여 차량탑재형 중량표시기(이하 자중계)를 운송차량에 설치하고, 여기서 얻어진 실시간 중량/위치정보를 활용하여 효율적으로 건설폐기물의 총량 및 재활용량을 관리할 수 있는 관제기술의 사례연구를 수행하였다. 연구결과 건설폐기물의 총량을 실시간으로 모니터링 할 수 있으며, 운송차량의 실시간 운송량, 운송거리, 운송시간 등을 관리하여 운행패턴 분석을 통한 물류운송 효율화 방안을 도출할 수 있음을 확인하였으며, 과적의 발생 시 적재를 제어함으로써 사전에 과적운행을 예방할 수 있음을 확인하였다.

엔진 흡입.압축과정의 유동해석을 위한 난류모델의 평가 (Assessment of Turbulence Models for Engine Intake and Compression Flow Analysis)

  • 박권하;김재곤
    • Journal of Advanced Marine Engineering and Technology
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    • 제32권8호
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    • pp.1129-1140
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    • 2008
  • Many turbulence models have been developed in order to analyze the flow characteristics in an engine cylinder. Watkins introduced k-${\varepsilon}$ turbulence model for in-cylinder flow, and Reynolds modified turbulence dissipation rate by applying rapid transformation theory, Wu suggested k-${\varepsilon}-{\tau}$ turbulence model in which length scale and time scale are separated to introduce turbulence time scale, and Orszag proposed k-${\varepsilon}$ RNG model. This study applied the models to in-cylinder flow induced by intake valve and piston moving. All models showed similar flow fields during early stage of intake stroke. At the end of compression stroke, ${\kappa}-{\varepsilon}$ Watkins, ${\kappa}-{\varepsilon}$ Reynolds and ${\kappa}-{\varepsilon}$ RNG predicted well second and third vortex, especially ${\kappa}-{\varepsilon}$ RNG produced new forth vortex near central axis at the lower part of cylinder which was not predicted by the other models.

LONG-TERM STREAMFLOW SENSITIVITY TO RAINFALL VARIABILITY UNDER IPCC SRES CLIMATE CHANGE SCENARIO

  • Kang, Boo-sik;Jorge a. ramirez, Jorge-A.-Ramirez
    • Water Engineering Research
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    • 제5권2호
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    • pp.81-99
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    • 2004
  • Long term streamflow regime under virtual climate change scenario was examined. Rainfall forecast simulation of the Canadian Global Coupled Model (CGCM2) of the Canadian Climate Center for modeling and analysis for the IPCC SRES B2 scenario was used for analysis. The B2 scenario envisions slower population growth (10.4 billion by 2010) with a more rapidly evolving economy and more emphasis on environmental protection. The relatively large scale of GCM hinders the accurate computation of the important streamflow characteristics such as the peak flow rate and lag time, etc. The GCM rainfall with more than 100km scale was downscaled to 2km-scale using the space-time stochastic random cascade model. The HEC-HMS was used for distributed hydrologic model which can take the grid rainfall as input data. The result illustrates that the annual variation of the total runoff and the peak flow can be much greater than rainfall variation, which means actual impact of rainfall variation for the available water resources can be much greater than the extent of the rainfall variation.

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