• 제목/요약/키워드: reference order

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표준준기에 의한 일사계 교정 (Thermopile Radiometer Calibration Using Reference Instrument)

  • 조덕기;윤창열;김광득;강용혁
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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    • pp.199.2-199.2
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    • 2010
  • The main purpose of the calibration procedure is to perform a one to one comparison of the reference pyranometer and the test pyranometer. In order to achieve this, both pyranometers need to be exposed to exactly the same irradiance, under the same circumstances. There are a number of error sources that could result in a wrong measurement. Most importantly Lamp instability, pyranometer offsets, thermal offsets of junctions, voltmeter offset, voltmeter instability, reference pyranometer instability, tilting of the pyranometers and differences in sensor height. Another sun-disc calibration procedure compares the computed vertical component of the direct irradiance as measured by a pyranometer with that measured by the pyranometer to be calibrated. Readings are taken with the levelled pyranometer on a clear day. Firstly the global irradiance and then the diffuse component are measured. Simultaneously measurement of direct irradiance is made with the pyrheliometer. The ways of performing the calibration and the subsequent calculation have been chosen such that the effect all these error sources has been eliminated as much as possible.

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교차 참조 점을 이용한 정지영상의 워터마크 삽입기법 (A Watermark Embedding Technique for Still Images Using Cross-Reference Points)

  • 이항찬
    • 대한전기학회논문지:시스템및제어부문D
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    • 제55권4호
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    • pp.165-172
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    • 2006
  • In this paper we present a technique for detecting cross-reference points that allows improving watermark detect-ability. In general, Harris detector is commonly used for finding salient points. Harris detector is a kind of combined corner and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. The new method proposed in this paper used not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we constructed pre-specified number of virtual lines from top to bottom and left to right, and several of cross points were selected by a random key. These selected points specify almost same positions with the accuracy more than that of Harris detector after digital attacks. These points were arranged by a random key, and blocks centered in these points were formed. A reference watermark is formed by a block and embedded in the next block. Because same alteration is applied to the watermark generated and embedded blocks. the detect-ability of watermark is improved even after digital attacks.

Standard Implementation for Privacy Framework and Privacy Reference Architecture for Protecting Personally Identifiable Information

  • Shin, Yong-Nyuo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제11권3호
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    • pp.197-203
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    • 2011
  • Personal Identifiable Information (PII) is considered information that identifies or can be used to identify, contact, or locate a person to whom such information pertains or that is or might be linked to a natural person directly or indirectly. In order to recognize such data processed within information and communication technologies such as PII, it should be determined at which stage the information identifies, or can be associated with, an individual. For this, there has been ongoing research for privacy protection mechanism to protect PII, which now becomes one of hot issues in the International Standard as privacy framework and privacy reference architecture. Data processing flow models should be developed as an integral component of privacy risk assessments. Such diagrams are also the basis for categorizing PII. The data processing flow may not only show areas where the PII has a certain level of sensitivity or importance and, as a consequence, requires the implementation of stronger safeguarding measures. This paper propose a standard format for satisfying the ISO/IEC 29100 "Privacy Framework" and shows an implementation example for privacy reference architecture implementing privacy controls for the processing of PII in information and communication technology.

Forward Kinematics 모델을 이용한 자동차 운전공간의 설계 (A Driver Space Design of Passenger Vehicle using Forward Kinematics Model)

  • 정성재;박민용
    • 대한인간공학회지
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    • 제21권2호
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    • pp.47-58
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    • 2002
  • This research suggested the mathematical model (forward kinematics method) to provide the reference points of driver space more easily and accurately in designing the package layout of vehicle interiors. For this purpose, the lengths of body segments of drivers and various joint angles occurred while were used. The length data between joints for the mathematical model were extracted from $SAFEWORK^{\circed{R}}$ as well as 95th percentile male and 5th percentile female body dimensions were utilized. In addition, the angles of body segments were applied on its diverse values within proper ranges in order to compare them each other. the mathematical model in this study was based on the concept of converting polar coordinate system to Cartesian coordinate system so that reference points of driver space were acquired in Cartesian coordinate system after using the segment lengths of drivers and the joint angles of driving postures as an input of polar coordinate system. It is expected that reference points of driver space obtained from this research are helpful to the study on package layout that is appropriate for physical characteristics of drivers.

Double Vector Based Model Predictive Torque Control for SPMSM Drives with Improved Steady-State Performance

  • Zhang, Xiaoguang;He, Yikang;Hou, Benshuai
    • Journal of Power Electronics
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    • 제18권5호
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    • pp.1398-1408
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    • 2018
  • In order to further improve the steady-state control performance of model predictive torque control (MPTC), a double-vector-based model predictive torque control without a weighting factor is proposed in this paper. The extended voltage vectors synthesized by two basic voltage vectors are used to increase the number of feasible voltage vectors. Therefore, the control precision of the torque and the stator flux along with the steady-state performance can be improved. To avoid testing all of the feasible voltage vectors, the solution of deadbeat torque control is calculated to predict the reference voltage vector. Thus, the candidate voltage vectors, which need to be evaluated by a cost function, can be reduced based on the sector position of the predicted reference voltage vector. Furthermore, a cost function, which only includes a reference voltage tracking error, is designed to eliminate the weighting factor. Moreover, two voltage vectors are applied during one control period, and their durations are calculated based on the principle of reference voltage tracking error minimization. Finally, the proposed method is tested by simulations and experiments.

개선된 SSTDR을 이용한 케이블 고장 검출과 위치 계산 (Detection and Location of Cable Fault Using Improved SSTDR)

  • 전정채;김재진;최명일
    • 전기학회논문지
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    • 제65권9호
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    • pp.1583-1589
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    • 2016
  • This paper proposes an improved spread spectrum time domain reflectometry (ISSTDR) using time-frequency correlation and reference signal elimination method in order to have more accurate fault determination and location detection than conventional (SSTDR) despite increased signal attenuation due to the long distance to cable fault location. The proposed method has a two-step process: the first step is to detect a peak location of the reference signal using time-frequency correlation analysis, and the second step is to detect a peak location of the correlation coefficient of the reflected signal by removing the reference signal. The proposed method was validated through comparison with existing SSTDR methods in open-and short-circuit fault detection experiments of low voltage power cables. The experimental results showed that the proposed method can detect correlation coefficients at fault locations accurately despite reflected signal attenuation so that cable faults can be detected more accurately and clearly in comparison to existing methods.

담수직파재배 논벼의 기준작물 잠재증발산량 산정방법별 작물계수의 변화 (Variation of Crop Coefficient With Respect to the Reference Crop Evapotranspiration Estimation Methods in Ponded Direct Seeding Paddy Rice)

  • 정상옥
    • 한국농공학회지
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    • 제39권4호
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    • pp.114-121
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    • 1997
  • In order to provide basic information for the estimation of evapotranspiration in the ponded direct seeding paddy field, both field lysimeter experiment and model prediction were performed to estimate daily ET. Various methods were used to predict daily reference crop ET and crop coefficients. Measure4 mean daily ET during the 1995 growing season varied from 5.9 to 6.1 mm depending on the species, while it varied from 5.1 to 5.5 mm in 1996. Model predicted mean daily ET during the 1995 growing season varied from 3.9 to 4.9 mm depending on the prediction model, while it varied from 3.5 to 4.7 mm in 1996. The smaller ET values both measured and predicted in 1996 were caused by the low values of temperature, sunshine hours, and solar radiation. Crop coefficients varied from 1.20 to 1.50 in 1995 depending on the prediction model, while it varied from 1.10 to 1.47 in 1996. Comparison of the seven reference crop ET prediction methods used in this study shows that the Penman-Monteith method and the FAO-Radiation method gave the lowest ET while the corrected Penman method and the Hargreaves method gave the largest ET. Since crop coefficients vary to a large extent based on the prediction methods, reference crop ET prediction method should be carefully selected in irrigation planning.

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Research on Relationship between Natural Vibration Periods and Structural Heights for High-rise Buildings and Its Reference Range in China

  • Xu, Peifu;Xiao, Congzhen;Li, Jianhui
    • 국제초고층학회논문집
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    • 제3권1호
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    • pp.49-64
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    • 2014
  • Natural vibration period is an important parameter for high-rise building, Based on 414 high-rise buildings completed or passed over-limit approval in China, the distribution law of natural vibration periods is analyzied. In order to satisfy the design requirements, such as global stability, story drift limit and minimum shear-gravity ratio, the reference ranges of fundamental periods $T_1$ are $0.3{\sqrt{H}}{\sim}0.4{\sqrt{H}}$ when the structural heights $H{\geq}250m$, when 150 m ${\leq}$ H < 250m, $T_1=0.25{\sqrt{H}}{\sim}0.4{\sqrt{H}}$, when 100 m ${\leq}$ H < 150 m, $T_1=0.2{\sqrt{H}}{\sim}0.35{\sqrt{H}}$, when 50 m $ {\leq}$ H < 100m, $T_1=0.15{\sqrt{H}}{\sim}0.3{\sqrt{H}}$. These can provide reference data for controlling mass and rigidity of high-rise buildings.

알도로시 건축의 '창발의 새로움'에 관한 연구 (A Study on Emergent Novelty of Aldo Rossi's Architecture)

  • 안지혜;이동언
    • 건축역사연구
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    • 제22권3호
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    • pp.37-48
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    • 2013
  • The purpose of this study is to evaluate Aldo Rossi's work as representation or non-representation, for some hold that the works of Aldo Rossi are representative and others say that they are non-representative. According to the three kinds of novelties appearing after Stephen Pepper's concept, "the breaking of reference" happens, and Aldo Rossi's concept, "the sense of deposition" Rossi's work is uncovered as non-representation. In order to clarify Rossi's work as non-representation, we are going to borrow Pepper's terms, intrusive novelty, emergent novelty, and naive novelty. The breaking of reference accompanies intrusive novelty to bring a sense of representation, emergent novelty to intuit a sense of non-representation, and naive novelty to a sense of newness of disorder. We hope to verify a hypothesis that Aldo Rossi's architectural thought and the architecture come from 'emergent novelty' on the basis of his two books, A Scientific Autobiography and Architecture of the City. Also this paper discusses qualitative aspects rather than visual aspects. The main concepts of emergent novelty are applied to Aldo Rossi's works and his thought. Finally this paper verifies 'the hypothesis' through revealing what Aldo Rossi means by the quality of suspension, the sense of deposition, and idea of the unfinished(repetition). Rossi's work is not textural reference of representation appearing after blocking, but qualitative reference of non-representation.

유도전동기의 속도 센서 없는 견실한 벡터 제어 (Rubust Vector Control of an Induction Motor without Speed Sensor)

  • 박태식;김성환;김남정;유지윤;박귀태
    • 전기전자학회논문지
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    • 제1권1호
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    • pp.55-63
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    • 1997
  • 본 논문의 목적은 유도 전동기의 속도 센서 없는 견실한 벡터 제어의 구현에 있다. 이를 위해 MRAS(Model Reference Adaptive System)를 사용하여 유도 전동기의 속도를 추정하였고 파라미터 변동에 견실한 두 개의 회전자 자속 관측기를 설계하여 MRAS 속도 추정기에 기준 모델과 추정 모델로 사용하였다. MRAS에 근거를 둔 전체 제어 기법은 2.2kW 유도 전동기의 벡터 제어 드라이브를 사용하여 실현되었으며, 본 논문에서 제한한 속도 센서 없는 벡터 제어 기법이 기존의 속도 센서 없는 제어 기법에 비해 보다 안정하고 견실함을 증명하였다.

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