• 제목/요약/키워드: reflected energy

검색결과 446건 처리시간 0.034초

Plane wave propagation in transversely isotropic magneto-thermoelastic rotating medium with fractional order generalized heat transfer

  • Lata, Parveen;Kaur, Iqbal
    • Structural Monitoring and Maintenance
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    • 제6권3호
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    • pp.191-218
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    • 2019
  • The aim of the present investigation is to examine the propagation of plane waves in transversely isotropic homogeneous magneto thermoelastic rotating medium with fractional order heat transfer. It is found that, for two dimensional assumed model, there exist three types of coupled longitudinal waves (quasi-longitudinal, quasi-transverse and quasi-thermal waves). The wave characteristics such as phase velocity, attenuation coefficients, specific loss, penetration depths, energy ratios and amplitude ratios of various reflected and transmitted waves are computed and depicted graphically. The conservation of energy at the free surface is verified. The effects of rotation and fractional order parameter by varying different values are represented graphically.

Determining the complexity level of proceduralized tasks in a digitalized main control room using the TACOM measure

  • Inseok Jang;Jinkyun Park
    • Nuclear Engineering and Technology
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    • 제54권11호
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    • pp.4170-4180
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    • 2022
  • The task complexity (TACOM) measure was previously developed to quantify the complexity of proceduralized tasks conducted by nuclear power plant operators. Following the development of the TACOM measure, its appropriateness has been validated by investigating the relationship between TACOM scores and three kinds of human performance data, namely response times, human error probabilities, and subjective workload scores. However, the information reflected in quantified TACOM scores is still insufficient to determine the levels of complexity of proceduralized tasks for human reliability analysis (HRA) applications. In this regard, the objective of this study is to suggest criteria for determining the levels of task complexity based on logistic regression between human error occurrences in digitalized main control rooms and TACOM scores. Analysis results confirmed that the likelihood of human error occurrence according to the TACOM score is secured. This result strongly implies that the TACOM measure can be used to identify the levels of task complexity, which could be applicable to various research domains including HRA.

Plane harmonic waves in fractional orthotropic magneto-thermoelastic solid with rotation and two-temperature

  • Himanshi;Parveen Lata
    • Coupled systems mechanics
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    • 제12권2호
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    • pp.103-125
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    • 2023
  • The present research is focused on the study of plane harmonic waves in a two-dimensional orthotropic magneto-thermoelastic media with fractional order theory of generalized thermoelasticity in the light of two-temperature and rotation due to time harmonic sources. Here, we studied three types of waves namely quasi-longitudinal (QL), quasi-transverse (QTS) and quasi thermal (QT) waves. The variations in the wave properties such as phase velocity, attenuation coefficient and specific loss have been noticed with respect to frequency for the reflected waves. Further the value of amplitude ratios, energy ratios and penetration depth are computed numerically with respect to angle of incidence. The numerical simulated results are presented graphically to show the effect of fractional parameter based on its conductivity (0<α<1 for weak, α=1 for normal, 1<α≤2 for strong conductivity) on all the components.

The audit method of cooling energy performance in office building using the Simple Linear Regression Analysis Model

  • Park, Jin-Young;Kim, Seo-Hoon;Jang, Cheol-Young;Kim, Jong-Hun;Lee, Seung-Bok
    • KIEAE Journal
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    • 제15권5호
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    • pp.13-20
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    • 2015
  • Purpose: In order to upgrade the energy performance of existing building, energy audit stage should be implemented first because it is useful method to find where the problems occur and know how much time and cost consumption for retrofit. In overseas researches, three levels of audit is proposed whereas there are no standards for audit in Korea. Besides, most studies use dynamic simulation in detail like audit level 3 even though the level 2 can save time and cost than level 3. Thus, this paper focused on audit level 2 and proposed the audit method with the simple linear regression analysis model. Method: Two parameters were considered for the simple regression analysis, which were the monthly electric use and the mean outdoor temperature data. The former is a dependent variable and the latter is a independent variable, and the building's energy performance profile was estimated from the regression analysis method. In this analysis, we found the abnormal point in cooling season and the more detailed analysis were conducted about the three heat source equipments. Result: Comparing with real and predicted models, the total consumption of predicted model was higher than real value as 23,608 kWh but it was the results that was reflected the compulsory control in 2013. Consequently, it was analyzed that the revised model could save the cooling energy as well as reduce peak electric use than before.

망기색에 대한 연구 (Study on Visible Diagnosis of Energy and Color)

  • 김용찬;강정수
    • 동의생리병리학회지
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    • 제19권4호
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    • pp.840-847
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    • 2005
  • This study was written in order to help understanding of visible diagnosis of energy and color(기색). Visible diagnosis of energy and color is a very important factor of diagnosis and a necessary step of visible diagnosis. As human's body is under the control of spirit(신) and spirit(신) is stored by five viscera(오장), so spirit expresses the change of five viscera and is reflected by energy and color(기색). Strictly speaking, energy and color(기색) is not divided into each other. But, we can say that glittering glossy part belongs to energy(기) and blue, red, yellow, white and black part belongs to color(색). Various changes of energy and color(기색) observe the rules of yin-yang(음양). If we consider the interior and exterior(내외), top and bottom(상하), right and left(좌우), rise and fall(부침), clearness and muddiness(청탁), weak and severe(미심), spread and gather(산박), gloss and dness(택요) etc. we can decide the yin and yang(음양), inside and outside(표리), coldness and heatness(한열), truth and false(허보), life and death(생사) and prognosis. One man's own color is determined by the five human type(오형인), There are very various points of changing colors. As divided into principal groups, there are three main groups, that is, sky(천), earth(지) and man(인). A season(사시), day and night(주야) and cloud and clear(음청) belong to the factor of sky(천), a direction and configuration of the ground(지형) belong 治 the factor of earth(지), and motion and rest(동정), seven emotions(칠정), age and youth(노소), poor and rich(빈부) and high and low(귀천) belong to the factor of man(인).

농경지 관측을 위한 KOMPSAT 대기보정 적용 및 평가 (Application of Atmospheric Correction to KOMPSAT for Agriculture Monitoring)

  • 안호용;류재현;나상일;소규호;이경도
    • 대한원격탐사학회지
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    • 제37권6_3호
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    • pp.1951-1963
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    • 2021
  • 농업환경 모니터링에서 지구관측위성을 활용한 원격탐사 자료는 시·공간적 그리고 효율성 측면에서 다른 방법에 비해 많은 이점을 가진다. 위성에 탑재된 센서는 태양광이 지표면에 반사되어 들어오는 에너지를 측정하므로, 지구의 대기에 의해 산란·흡수·반사되는 과정에서 잡음이 발생한다. 따라서 지표면에 반사되는 에너지(복사휘도)를 정확히 측정하기 위해서는 대기의 효과에 의한 잡음을 제거해야하는 대기보정이 선행되어야 한다. 본 연구는 KOMPSAT-3 위성의 대기보정 적용 및 농업분야 활용성 평가를 위해 대기보정 민감도 분석, 위성 상호간 교차 분석, 지상관측자료와 비교 분석을 수행하였다. 그 결과 모든 경우에서 대기보정 후 표면 반사율이 대기보정 전 TOA 반사율 보다 상호 일치율이 높게 나타났으며 동일한 기준의 시계열 식생지수 생산이 가능할 것으로 판단된다. 하지만 대기입력 파라미터의 민감도 및 위성촬영각(Tilt)에 대한 정량적인 분석을 위한 추가 연구가 필요하다.

폐기물처리시설의 세부검사방법 마련연구(II): 세부검사방법 문제점도출 및 개선방향 설정 (A study on inspection methods for waste treatment facilities(II): Derivation of problems and improvement direction in inspection methods)

  • 이풀잎;권은혜;손준익;강준구;전태완;이동진
    • 유기물자원화
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    • 제31권1호
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    • pp.85-100
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    • 2023
  • 본 연구는 폐기물처리시설의 설치·정기검사방법 개선을 도모하기 위해 6개 분야로 분류된 폐기물처리시설을 현장조사하여 검사방법의 문제점을 파악하고 그에 따른 개선방향을 마련하여 폐기물처리시설 세부검사방법을 개정하고자 하였다. 그 결과 소각, 소각열회수 분야에서는 열화상카메라를 활용한 전체온도 측정 및 1년간의 TMS 데이터를 비교 등의 검사방법을 마련하였으며, 멸균분쇄시설의 경우 「폐기물의 조성비 검사」는 검사자 및 피검사자의 안전상의 이유로 폐기물을 개봉하지 않고 서류로 대체할 수 있도록 적용하였다. 매립시설의 경우 영상정보처리기기 활용 및 매립시설 상부를 덮는 시설물의 관리에 대한 내용 등 법에는 제시되어 있으나 세부검사방법이 마련되어있지 않은 항목을 세부검사방법에 적용하였다. 음식물류폐기물처리시설의 경우 민원의 주요원인인 악취관리에서 악취배출허용기준을 준수하도록 검사방법을 마련하였다. 그 결과, 소각 및 멸균분쇄, 시멘트소성로, 소각열회수시설에서는 총 18개의 개선(안) 중 10개가 반영되었으며, 매립시설의 경우 총 12개의 개선(안)중에서 11개가 반영되었다. 또한 음식물류폐기물처리시설의 경우 총 12개의 개선(안)중에서 10개가 반영되어 총 31개의 검사방법이 개선되었다.

이온주입 에너지에 따른 Auger Si KLL Peak Shift 및 Ti 계열 화합물의 Chemical State 관찰

  • 허성;박윤백;민경열;이순영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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    • pp.83-83
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    • 1999
  • 본 연구에서는 Auger Elecrtron Spectroscopy (AES) 장비를 이용하여 Silicone Wafer 표면에 BF 이온을 주입시킨 후 Dopping 농도 및 Implantation 에너지에 따른 Si KLL Peak의 변화를 관찰하였다. 또한 PVD Ti 계열 화학물의 시료에 대하여 Peak의 Shape 변화를 관찰하였다. 1)Dopping 농도 및 Implantation 에너지에 따른 Si KLL Peak의 변화 관찰 일반적으로 Silicone 기판에 Arsenic(3가)을 Dopping 하였을 경우, Si KLL Peak의 Kinetic Energy 값은 순수 Si Peak보다 더 작은 값으로 Shift 하며, Boron (5가)을 Dopping하였을 경우에는 더 큰 값으로 Shift 한다. 이론적으로 N-type Si의 에너지 차이는 약 1.0eV로 보고되어 있으며, AES를 이용하여 실험적으로 측정된 값은 약 0.6eV정도로 알려져 있다. 이러한 차이는 Dopping 농도에 따라 Valance Band의 에너지 값이 변화하기 때문이라고 알려져 있다. 본 연구에서는 BF2를 Si에 이온 주입하여 입사 에너지 및 dose 량에 따른 Si KLL Peak의 변화를 관찰하였다. 그림1과 같이 Si KLL Peak는 Implantation Energy가 작을수록 Kinetic Energy가 높은 곳으로 Shift 한다. 이는 LOw Energy로 이온 주입하면, Projected Range (Rp)가 High Energy로 이온 주입할 때보다 작기 때문이며, 이 결과를 Secondary Ion Mass Spectroscopy (SIMS) 및 TRIM simulation을 이용하여 확인하였다. 또한 표면에서의 전자 Density의 변화와 Implantation energy와의 관계를 시료의 표면에서 반사되어 나오는 전자의 에너지 손실(Reflected Electron Energy Loss Spectroscopy:REELS)을 통하여 고찰하였다. 2) PVD Ti 계열화합물의 시료에 대한 peak의 shape 가 변화하며, TiL3M23V (Ti2) 및 TiL3M23M23 (Til) Peak의 Intensity Ratio가 변화한다. 따라서 본 연구에서는 그림 2와 같이 Ti 결합 화합물에서의 Ti Auger Peak의 특성 에너지 값과 Peak Shape를 관찰하여, AES를 이용하여 Ti 계열의 화합물에 대한 Chemical state 분석의 가능성을 평가하였다.

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수정된 방사 에너지법과 단파장 영역 보정법을 이용한 파랑 중 부가저항 추정에 관한 연구 (A Study on Estimation of Added Resistance in Waves Using Modified Radiated Energy Method and Short Wave Correction Method)

  • 오승훈;양진호
    • 대한조선학회논문집
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    • 제53권1호
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    • pp.62-68
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    • 2016
  • A simple calculation tool for added resistance in waves is developed to utilize for initial design or embedded module for navigation support system. In order to select an appropriate calculation method for added resistance in waves, three methods (drift method, integrated pressure method, radiated energy method) based on strip method are applied to Wigley I and KVLCC2. The methods for added resistance in waves give the underestimated results because it is difficult to consider nonlinear effects due to reflected wave. We apply asymptotic (Faltinsen's method) and empirical formula (NMRI's method) to improve the accuracy for short wave length region. In comparison with experimental results, the combination of radiated energy method and short wave correction method of NMRI is the most reasonable. However, a simple sum of results calculated by two methods gives rise to the overestimation of added resistance for short wave length region because added resistance of radiated energy method exits in total reflection region. To overcome this problem, modified radiated energy method is proposed using correction coefficient defined by reflection coefficient of NMRI's method. Finally, added resistance in regular waves is composed of added resistance of modified radiated energy method and that of short wave correction method of NMRI. Estimated added resistance in regular waves is validated by comparison with experimental results of other research groups.

75 kW 용융탄산염 연료전지 (MCFC) 스택 내 압력 손실 해석 (Pressure Loss Analysis of the 75 kW MCFC Stack with Internal Manifold Separator)

  • 김범주;이정현;김도형;강승원;임희천
    • 한국수소및신에너지학회논문집
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    • 제19권5호
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    • pp.367-376
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    • 2008
  • To obtain the data of the pressure loss and differential pressure at the inside of the stack that was composed of 126 cells with 7,500 cm2 electrode area, 75kW molten carbonate fuel cell system has been operated. Computational fluid dynamics was applied to estimate reactions and thermal fluid behavior inside of the stack that was adopted with internal manifold type separator. The pressure loss coefficient K showed 72.29 to 84.01 in anode and 6.34 to 8.75 in cathode at low part of cells at the inside of 75 kW MCFC stack respectively. Meanwhile, the pressure loss coefficient of the higher part of cells at the interior of the stack showed 15.36 and 56.44 in anode and cathode respectively. These results mean that there is no big total pressure difference between anode and cathode at the inner part of 75 kW MCFC stack. This result will be reflected in 250kW MCFC system design.