• 제목/요약/키워드: Laboratory parameters

검색결과 2,806건 처리시간 0.028초

산-염기 적정 시스템의 비선형 회귀분석에 관한 고찰 (Nonlinear Regression Analysis of Acid-Base Titration System)

  • 박정오;홍재진
    • 대한임상검사과학회지
    • /
    • 제40권1호
    • /
    • pp.18-25
    • /
    • 2008
  • In classical titrimetric analyses, the major concern is the concentration of titrant, usually the aqueous solution of hydrochloric acid or sodium hydroxide, that could be changed as time goes by and it is accompanied with the inaccuracy of the resulting data. And the statistical approach, the nonlinear regression analysis, which is a well-known statistical method, was introduced to determine the accurate concentration of the titrant and the exact value of parameters, $K_a$, r, $C_a$, $C_b$, for 0.01 M aqueous solutions of analytes, sodium pyruvate, sodium acetate, sodium bicarbonate, ammonium hydroxide, ammonium chloride and acetic acid at $25^{\circ}C$. We used Gauss-Newton method for the linearlization of the nonlinear titration system and the two-parameter fitting showed appreciable convergent data for the parameters of the analytes set with the various range of $K_a$ value.

  • PDF

골재의 동적 거동 모사를 위한 DEM 입력변수의 결정 연구 (Determination of DEM Input Parameters for Dynamic Behavior Simulation of Aggregates)

  • 윤태영;유평준;김연복
    • 한국도로학회논문집
    • /
    • 제16권1호
    • /
    • pp.21-30
    • /
    • 2014
  • PURPOSES : Evaluation of input parameters determination procedure for dynamic analysis of aggregates in DEM. METHODS : In this research, the aggregate slump test and angularity test were performed as fundamental laboratory tests to determine input parameters of spherical particles in DEM. The heights spreads, weights of the simple tests were measured and used to calibrate rolling and static friction coefficients of particles. RESULTS : The DEM simulations with calibrated parameters showed good agreement with the laboratory test results for given dynamic condition. CONCLUSIONS : It is concluded that the employed calibration method can be applicable to determine rolling friction coefficient of DEM simulation for given dynamic conditions. However, further research is necessary to connect the result to the behavior of aggregate in packing and mixing process and to refine static friction coefficient.

Fast speaker adaptation using extended diagonal linear transformation for deep neural networks

  • Kim, Donghyun;Kim, Sanghun
    • ETRI Journal
    • /
    • 제41권1호
    • /
    • pp.109-116
    • /
    • 2019
  • This paper explores new techniques that are based on a hidden-layer linear transformation for fast speaker adaptation used in deep neural networks (DNNs). Conventional methods using affine transformations are ineffective because they require a relatively large number of parameters to perform. Meanwhile, methods that employ singular-value decomposition (SVD) are utilized because they are effective at reducing adaptive parameters. However, a matrix decomposition is computationally expensive when using online services. We propose the use of an extended diagonal linear transformation method to minimize adaptation parameters without SVD to increase the performance level for tasks that require smaller degrees of adaptation. In Korean large vocabulary continuous speech recognition (LVCSR) tasks, the proposed method shows significant improvements with error-reduction rates of 8.4% and 17.1% in five and 50 conversational sentence adaptations, respectively. Compared with the adaptation methods using SVD, there is an increased recognition performance with fewer parameters.

Direct Observation of Radiative Flux in the Southern Yellow Sea

  • Lu, Lian-Gang;Yu, Fei;Diao, Xinyuan;Guo, Jingsong;Wang, Huiwu;Wei, Chuanjie
    • Ocean Science Journal
    • /
    • 제43권2호
    • /
    • pp.115-126
    • /
    • 2008
  • Direct measurements of four radiative components at air-sea boundary layer were conducted in the southern Yellow Sea during three cruises (seasons) in 2007. Simultaneous observations of meteorological (cloud cover, air temperature and humidity) and oceanographic (sea surface temperature) parameters were carried out. Observational results of radiative fluxes and meteorological and oceanographic parameters are presented. Mean diurnal cycles of four radiative components, net radiation, and sea surface albedo are calculated to achieve averages in different seasons. Net radiative fluxes in three seasons (winter, spring, autumn) are 8, 146, $60\;W/m^2$, respectively. Comparisons between the observed radiative fluxes and those estimated with formulas are taken.

Probabilistic Bilinear Transformation Space-Based Joint Maximum A Posteriori Adaptation

  • Song, Hwa Jeon;Lee, Yunkeun;Kim, Hyung Soon
    • ETRI Journal
    • /
    • 제34권5호
    • /
    • pp.783-786
    • /
    • 2012
  • This letter proposes a more advanced joint maximum a posteriori (MAP) adaptation using a prior model based on a probabilistic scheme utilizing the bilinear transformation (BIT) concept. The proposed method not only has scalable parameters but is also based on a single prior distribution without the heuristic parameters of the previous joint BIT-MAP method. Experiment results, irrespective of the amount of adaptation data, show that the proposed method leads to a consistent improvement over the previous method.

A New Support Vector Machine Model Based on Improved Imperialist Competitive Algorithm for Fault Diagnosis of Oil-immersed Transformers

  • Zhang, Yiyi;Wei, Hua;Liao, Ruijin;Wang, Youyuan;Yang, Lijun;Yan, Chunyu
    • Journal of Electrical Engineering and Technology
    • /
    • 제12권2호
    • /
    • pp.830-839
    • /
    • 2017
  • Support vector machine (SVM) is introduced as an effective fault diagnosis technique based on dissolved gases analysis (DGA) for oil-immersed transformers with maximum generalization ability; however, the applicability of the SVM is highly affected due to the difficulty of selecting the SVM parameters appropriately. Therefore, a novel approach combing SVM with improved imperialist competitive algorithm (IICA) for fault diagnosis of oil-immersed transformers was proposed in the paper. The improved ICA, which is proved to be an effective optimization approach, is employed to optimize the parameters of SVM. Cross validation and normalizations were applied in the training processes of SVM and the trained SVM model with the optimized parameters was established for fault diagnosis of oil-immersed transformers. Three classification benchmark sets were studied based on particle swarm optimization SVM (PSOSVM) and IICASVM with four multiple classification schemes to select the best scheme for transformer fault diagnosis. The results show that the proposed model can obtain higher diagnosis accuracy than other methods. The comparisons confirm that the proposed model is an effective approach for classification problems.

On the wave dispersion and vibration characteristics of FG plates resting on elastic Kerr foundations via HSDT

  • Bennai, Riadh;Fourn, Hocine;Nebab, Mokhtar;Atmane, Redhwane Ait;Mellal, Fatma;Atmane, Hassen Ait;Benadouda, Mourad;Touns, Abdelouahed
    • Advances in concrete construction
    • /
    • 제14권3호
    • /
    • pp.169-183
    • /
    • 2022
  • In this article, vibrational behavior and wave propagation characteristics in (FG) functionally graded plates resting on Kerr foundation with three parameters is studied using a 2D dimensional (HSDT) higher shear deformation theory. The new 2D higher shear deformation theory has only four variables in field's displacement, which means has few numbers of unknowns compared with others theories. The shape function used in this theory satisfies the nullity conditions of the shear stresses on the two surfaces of the FG plate without using shear correction factors. The FG plates are considered to rest on the Kerr layer, which is interconnected with a Pasternak-Kerr shear layer. The FG plate is materially inhomogeneous. The material properties are supposed to vary smoothly according to the thickness of the plate by a Voigt's power mixing law of the volume fraction. The equations of motion due to the dynamics of the plate resting on a three-parameter foundation are derived using the principle of minimization of energies; which are then solved analytically by the Navier technique to find the vibratory characteristics of a simply supported plate, and the wave propagation results are derived by using the dispersion relations. Perceivable numerical results are fulfilled to evaluate the vibratory and the wave propagation characteristics in functionally graded plates and some parameters such wave number, thickness ratio, power index and foundation parameters are discussed in detail.

양면형 태양광발전 소자의 성능변수 및 이에 대한 정확한 측정방법 (Performance Parameters of a Bifacial PV Device and Accurate Measurement Method for the Parameters)

  • 안승규;안세진;어영주;유진수;박주형;김기환;조아라;조준식;윤재호;신동협;정인영;곽지혜
    • Current Photovoltaic Research
    • /
    • 제5권3호
    • /
    • pp.89-94
    • /
    • 2017
  • We have examined the issues on the measurement of bifacial photovoltaic(PV) devices that should be considered in order to ensure a measurement accuracy beyond a certain level and the comparability between the bifacial PV devices. Based on the results of various experiments and previous studies, solutions for these measurement issues are suggested. The most significant technical issues in the performance measurement of the bifacial PV devices are 1) elimination of the effect due to the light reflection on the sample holder surface and 2) the measurement of the expected power generation gain in outdoor operation. The effect due to the light reflection on the sample holder surface can be eliminated by using an anti-reflective sample holder. In case of a reflective sample holder, if the bifacial device have a linear characteristic with respect to the irradiance of incident light, it has been confirmed (through some previous studies and additional experiment) that exact measurement results can be obtained by the correction of the measurement data. In addition, it was also confirmed that the expected power generation gain in the outdoor operation can be obtained by three different methods along with the basic concepts of the bifaciality coefficient, the albedo, and the effective front irradiance.

Exploring precise deposition and influence mechanism for micro-scale serpentine structure fiber

  • Wang, Han;Ou, Weicheng;Zhong, Huiyu;He, Jingfan;Wang, Zuyong;Cai, Nian;Chen, XinDu;Xue, Zengxi;Liao, Jianxiang;Zhan, Daohua;Yao, Jingsong;Wu, Peixuan
    • Advances in nano research
    • /
    • 제12권2호
    • /
    • pp.151-165
    • /
    • 2022
  • Micro-scale serpentine structure fibers are widely used as flexible sensor in the manufacturing of micro-nano flexible electronic devices because of their outstanding non-linear mechanical properties and organizational flexibility. The use of melt electrowriting (MEW) technology, combined with the axial bending effect of the Taylor cone jet in the process, can achieve the micro-scale serpentine structure fibers. Due to the interference of the process parameters, it is still challenging to achieve the precise deposition of micro-scale and high-consistency serpentine structure fibers. In this paper, the micro-scale serpentine structure fiber is produced by MEW combined with axial bending effect. Based on the controlled deposition of MEW, applied voltage, collector speed, nozzle height and nozzle diameter are adjusted to achieve the precise deposition of micro-scale serpentine structure fibers with different morphologies in a single motion dimension. Finally, the influence mechanism of the above four parameters on the precise deposition of micro-scale serpentine fibers is explored.