• Title/Summary/Keyword: Energy linearity

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Compressional Properties of Fabrics at Low Pressure to Assess Real Fabric Handle (직물의 태 예측에 근접한 직물의 저응력 압축특성 측정)

  • Na, Young-Joo
    • Fashion & Textile Research Journal
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    • v.1 no.4
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    • pp.358-362
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    • 1999
  • Twenty-three fabrics of varying thicknesses and weights were subjected to the maximum pressures of 10, 20, 35, 50 and 70 $gf/cm^2$ to yield pressure-thickness curves. Compression property values were plotted according to the amount of pressure applied to the samples. Pressure increases resulted in decreases in LC (compressional curve linearity), increases in WC (compressional energy) and no change in RC (compressional resilience). The best-fit lines are found separately according to pressures. The thickest fabrics exhibited the highest LC and WC values. The slopes varied different according to the pressure applied, with a pressure 50 $gf/cm^2$ exhibiting the steepest slope at We. The pressure of 20 $gf/cm^2$ correlated most closely with the hand-evaluation test results, yielding Spearmans correlation coefficients of .86 and .82 respectively for the LC and WC.

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Technology of Fuel cell stack fault detection by THDA (전고조파 왜율 분석을 통한 연료전지 스택 고장진단 기술)

  • Kim, UckSoo;Park, HyunSeok;Kang, SunDoo;Eom, JeongYong
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.90.1-90.1
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    • 2011
  • This technology is applicable to Electrical vehicle that using Energy from Hydrogen Fueled Cell. Electricity & water is got from chemical reaction between H2 & O2 in stack. This technology is used when fault diagnosis of Fuel cell is needed. It is General method that measure each cell's voltage of stack for fault diagnosis. but, this technology is method of measuring entire voltage of stack. For this reason, fault diagnosis system is simplified and cost of system is lower than previous one. In normal stack condition, characteristic graph of voltage-current has linearity. In fault stack condition, it has non-linearity. we use this characteristic to diagnosis of stack fault. In this technology, Specific frequency current is injected into stack & Stack voltage is measured in response. After that, stack voltage difference is analyzed to diagnosis of stack fault. Presently, Development of current injection module & basic program of THDA is finished. in future we will develop the technology of precise measurement technology about entire stack voltage.

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Measuring Absorbed Dose from Medical X-ray Equipment Using Optically Stimulated Luminescence Dots (광자극선량계의 저에너지 엑스선 특성비교)

  • Jung, Sook Jin;Jin, Gye Hwan
    • Journal of the Korean Society of Radiology
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    • v.12 no.1
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    • pp.79-83
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    • 2018
  • In this paper, we measured and analyzed the dose correction factor, absorbed dose linearity, peak voltage X-ray response, angular dependence. Exposure dose correction factor, absorbed dose linearity, and peak voltage linearity using the medical X-ray generator were all in accordance with IEC-62387-1 (2007). The reference to the dosimetry direction at 0, 30, and 60 degrees relative to baseline radiation exposure was -29% (${\pm}30^{\circ}$) and + 67% (${\pm}60^{\circ}$). The values measured at $30^{\circ}$ were -8% lower than the standard and -18% lower than the standard at $60^{\circ}$. Therefore, the effect of direction should be corrected when using OSL dot dosimeter.

A 10-Bit 75-MHz CMOS Current-Mode Digital-to-Analog Converter for HDTV Applications (HDTV용 10비트 75MHz CMOS 전류구동 D/A 변환기)

  • 이대훈;주리아;손영찬;유상대
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.689-692
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    • 1999
  • This paper describes a 10-bit 75-MHz CMOS current-mode DAC designed for 0.8${\mu}{\textrm}{m}$ double-poly double-metal CMOS technology. This D/A converter is implemented using a current cell matrix that can drive a resistive load without output buffer. In the DAC. a current source is proposed to reduce the linearity error caused by the threshold-voltage variations over a wafer and the glitch energy caused by the time lagging, The integral and differential linearity error are founded to be within $\pm$0.35 LSB and $\pm$0.31 LSB respectively. The maximum conversion rate is about 80 MS/s. The total power dissipation is 160 ㎽ at 75 MS/s conversion rate.

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Intermolecular Hydrogen Bond between Phenol and DMAs (Phenol과 DMA 간의 수소결합)

  • Kim, Pock-Hye;Lee, Ik-Choon
    • Journal of the Korean Chemical Society
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    • v.10 no.1
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    • pp.15-17
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    • 1966
  • Intermolecular hydrogen-bonding between phenol and N,N'-dimethylanilines (DMA) has been studied by infrared spectrophotometry. Results show that DMA acts as n-and ${\pi}$-donor although n-complex predominates. O-H stretching frequency shifts (${\Delta}{\nu}$) were proportional to basicitys of DMA and excellent linearity was observed between ${\Delta}{\nu}$ and the Hammett substituent constant, ${\sigma}$.

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Development of energy based Neuro-Wavelet algorithm to suppress structural vibration

  • Bigdeli, Yasser;Kim, Dookie
    • Structural Engineering and Mechanics
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    • v.62 no.2
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    • pp.237-246
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    • 2017
  • In the present paper a new Neuro-Wavelet control algorithm is proposed based on a cost function to actively control the vibrations of structures under earthquake loads. A wavelet neural network (WNN) was developed to train the control algorithm. This algorithm is designed to control multi-degree-of-freedom (MDOF) structures which consider the geometric and material non-linearity, structural irregularity, and the incident direction of an earthquake load. The training process of the algorithm was performed by using the El-Centro 1940 earthquake record. A numerical model of a three dimensional (3D) three story building was used to accredit the control algorithm under three different seismic loads. Displacement responses and hysteretic behavior of the structure before and after the application of the controller showed that the proposed strategy can be applied effectively to suppress the structural vibrations.

A Study on Development of a PIN Semiconductor Detector for Measuring Individual Dose (개인 선량 측정용 PIN 반도체 검출기 개발에 관한 연구)

  • Lee, B.J.;Lee, W.N.;Khang, B.O.;Chang, S.Y.;Rho, S.R.;Chae, H.S.
    • Journal of Radiation Protection and Research
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    • v.28 no.2
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    • pp.87-95
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    • 2003
  • The fabrication process and the structure of PIN semiconductor detectors have been designed optimally by simulation for doping concentration and width of p+ layer, impurities re-contribution due to annealing and the current distribution due to guard ring at the sliced edges. The characteristics to radiation response has been also simulated in terms of Monte Carlo Method. The device has been fabricated on n type, $400\;{\Omega}cm$, orientation <100>, Floating-Zone silicon wafer using the simulation results. The leakage current density of $0.7nA/cm^2/100{\mu}m$ is achieved by this process. The good linearity of radiation response to Cs-137 was kept within the exposure ranges between 5 mR/h and 25 R/h. This proposed process could be applied for fabricating a PIN semiconductor detector for measuring individual dose.

Effects of Fully Filling Deep Electron/Hole Traps in Optically Stimulated Luminescence Dosimeters in the Kilovoltage Energy Range

  • Chun, Minsoo;Jin, Hyeongmin;Lee, Sung Young;Kwon, Ohyun;Choi, Chang Heon;Park, Jong Min;Kim, Jung-in
    • Journal of Radiation Protection and Research
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    • v.47 no.3
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    • pp.134-142
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    • 2022
  • Background: This study investigated the characteristics of optically stimulated luminescence dosimeters (OSLDs) with fully filled deep electron/hole traps in the kV energy ranges. Materials and Methods: The experimental group consisted of InLight nanoDots, whose deep electron/hole traps were fully filled with 5 kGy pre-irradiation (OSLDexp), whereas the non-pre-irradiated OSLDs were arranged as a control group (OSLDcont). Absorbed doses for 75, 80, 85, 90, 95, 100, and 105 kVp with 200 mA and 40 ms were measured and defined as the unit doses for each energy value. A bleaching device equipped with a 520-nm long-pass filter was used, and the strong beam mode was used to read out signal counts. The characteristics were investigated in terms of fading, dose sensitivities according to the accumulated doses, and dose linearity. Results and Discussion: In OSLDexp, the average normalized counts (sensitivities) were 12.7%, 14.0%, 15.0%, 10.2%, 18.0%, 17.9%, and 17.3% higher compared with those in OSLDcont for 75, 80, 90, 95, 100, and 105 kVp, respectively. The dose accumulation and bleaching time did not significantly alter the sensitivity, regardless of the filling of deep traps for all radiation qualities. Both OSLDexp and OSLDcont exhibited good linearity, by showing coefficients determination (R2) > 0.99. The OSL sensitivities can be increased by filling of deep electron/hole traps in the energy ranges between 75 and 105 kVp, and they exhibited no significant variations according to the bleaching time.

On the analysis of delamination in multilayered inhomogeneous rods under torsion

  • Rizov, Victor I.
    • Coupled systems mechanics
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    • v.8 no.5
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    • pp.377-391
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    • 2019
  • The present paper is focused on analyzing the delamination of inhomogeneous multilayered rods of circular cross-section loaded in torsion. The rods are made of concentric longitudinal layers of individual thickness and material properties. A delamination crack is located arbitrary between layers. Thus, the internal and external crack arms have circular and ring-shaped cross-sections, respectively. The layers exhibit continuous material inhomogeneity in radial direction. Besides, the material has non-linear elastic behavior. The delamination is analyzed in terms of the strain energy release rate. General solution to the strain energy release rate is derived by considering the energy balance. The solution is applied to analyze the delamination of cantilever rod. For verification, the strain energy release rate is derived also by considering the complementary strain energy.

Evaluation of Applicability of Perovskite Dosimeter based on CsPbBr3 Material to Quality Assurance in Radiation Therapy (CsPbBr3을 기반으로 한 Perovskite 선량계의 방사선치료 Quality Assurance에 대한 적용가능성 평가)

  • Yang, Seung-Woo;Park, Sung-Kwang
    • Journal of the Korean Society of Radiology
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    • v.16 no.3
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    • pp.211-216
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    • 2022
  • In radiation therapy, accurate Quality Assurance (QA) is required to irradiate tumor tissue while minimizing damage to normal tissue. Therefore, a dosimeter that can accurately measure radiation is needed. The purpose of this study is to develop a highly efficient radiation dosimeter with high sensitivity by applying a particle in binder method that can reduce manufacturing costs and simplify processes to perovskite materials that are cheaper and simpler to manufacture. By evaluating the response characteristics to high-energy photon, the applicability of QA dosimeter to radiation therapy was evaluated. As a result of reproducibility evaluation, RSD at 6 MV energy was presented as 1.178% and 15 MV energy was presented as 1.141%. As a result of linearity evaluation according to linear regression analysis, R2 values of 0.9999 were presented under each condition of 6 MV and 15 MV energy. It was found that the CsPbBr3 dosimeter manufactured based on the results of reproducibility and linearity evaluation is highly applicable as a QA dosimeter in the field of therapeutic radiation. The CsPbBr3 dosimeter manufactured in this study presented more than the standard performance in the evaluation of reproducibility and linearity, and it can be used as a radiotherapy QA dosimeter through improvement.