Fabrication and spectral response analysis of AlGaAs/GaAs and InP/InGaAs HPTs with transparent ITO emitter contacts

1996 ◽  
Vol 143 (1) ◽  
pp. 89-93 ◽  
Author(s):  
S.A. Bashar ◽  
A.A. Rezazadeh
Keyword(s):  
Spectral Response ◽  
Response Analysis

A statistical study on artificially generated earthquake records

1976 ◽  
Vol 3 (1) ◽  
pp. 11-19
Author(s):  
W. K. Tso ◽  
B. P. Guru
Keyword(s):  
Statistical Study ◽  
Spectral Response ◽  
Flexible Structures ◽  
Time History ◽  
Maximum Response ◽  
Response Analysis ◽  
Seismic Region ◽  
Natural Period ◽  
Earthquake Records ◽  
Time History Response

A statistical study has been done to investigate (i) the variation of spectral responses of structures due to artificially generated earthquake records with identical statistical properties, (ii) the effect of duration of strong shaking phase of artificial earthquakes on the response of structures, and (iii) the number of earthquake records needed for time-history response analysis of a structure in a seismic region. The results indicate that the flexible structures are more sensitive to the inherent statistical variations among statistically identical earthquake records. Consequently several records must be used for time-history response analysis. A sample of eight or more records appear to provide a good estimate of mean maximum response. The duration of strong shaking can significantly affect the maximum response. Based on the results, it is suggested that for the purpose of estimating peak response, the strong shaking duration of the input earthquake motion should be at least four times the natural period of the structure. The maximum responses due to statistically identical ground motion records are observed to fit approximately the type 1 extreme value distribution. Thus, it is rationally possible to choose a design value based on the mean, standard deviation of the spectral response values and tolerable probability of exceedance.

Efficient Cu(In, Ga)Se2 Based Solar Cells Prepared by Electrodeposition

2003 ◽  
Vol 763 ◽  
Author(s):  
D. Guimard ◽  
N. Bodereau ◽  
J. Kurdi ◽  
J.F. Guillemoles ◽  
D. Lincot ◽  
...  
Keyword(s):  
Band Gap ◽  
Room Temperature ◽  
Open Circuit Voltage ◽  
Spectral Response ◽  
Deposition Process ◽  
Open Circuit ◽  
Response Analysis ◽  
Cell Parameters ◽  
Current Voltage ◽  
Capacitance Voltage

AbstractCuInSe2 and Cu(In, Ga)Se2 precursor layers have been prepared by electrodeposition, with morphologies suitable for device completion. These precursor films were transformed into photovoltaic quality films after thermal annealing without any post-additional vacuum deposition process. Depending on the preparation parameters annealed films with different band gaps between 1eV and 1.5 eV have been prepared. The dependence of resulting solar cell parameters has been investigated. The best efficiency achieved is about 10,2 % for a band gap of 1.45 eV. This device presents an open circuit voltage value of 740 mV, in agreement with the higher band gap value. Device characterisations (current-voltage, capacitance-voltage and spectral response analysis) have been performed. Admittance spectroscopy at room temperature indicates the presence of two acceptor traps at 0.3 and 0.43 eV from the valance band with density of the order of 2. 1017 cm-3 eV-1.

scholarly journals Spectral Response Analysis: An Indirect and Non-Destructive Methodology for the Chlorophyll Quantification of Biocrusts

2019 ◽  
Vol 11 (11) ◽  
pp. 1350 ◽  
Author(s):  
José Raúl Román ◽  
Emilio Rodríguez-Caballero ◽  
Borja Rodríguez-Lozano ◽  
Beatriz Roncero-Ramos ◽  
Sonia Chamizo ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Spectral Response ◽  
Soil Surface ◽  
Response Analysis ◽  
Surface Reflectance ◽  
Wide Range ◽  
Reflectance Analysis ◽  
Non Destructive

Chlorophyll a concentration (Chla) is a well-proven proxy of biocrust development, photosynthetic organisms’ status, and recovery monitoring after environmental disturbances. However, laboratory methods for the analysis of chlorophyll require destructive sampling and are expensive and time consuming. Indirect estimation of chlorophyll a by means of soil surface reflectance analysis has been demonstrated to be an accurate, cheap, and quick alternative for chlorophyll retrieval information, especially in plants. However, its application to biocrusts has yet to be harnessed. In this study we evaluated the potential of soil surface reflectance measurements for non-destructive Chla quantification over a range of biocrust types and soils. Our results revealed that from the different spectral transformation methods and techniques, the first derivative of the reflectance and the continuum removal were the most accurate for Chla retrieval. Normalized difference values in the red-edge region and common broadband indexes (e.g., normalized difference vegetation index (NDVI)) were also sensitive to changes in Chla. However, such approaches should be carefully adapted to each specific biocrust type. On the other hand, the combination of spectral measurements with non-linear random forest (RF) models provided very good fits (R2 > 0.94) with a mean root mean square error (RMSE) of about 6.5 µg/g soil, and alleviated the need for a specific calibration for each crust type, opening a wide range of opportunities to advance our knowledge of biocrust responses to ongoing global change and degradation processes from anthropogenic disturbance.

Current collection mechanisms in p-n junction a-Si:H solar cells using spectral response analysis

1980 ◽  
Author(s):  
M.K. Han ◽  
W.A. Anderson ◽  
R. Lahri ◽  
J. Coleman ◽  
H.J. Wiesmann
Keyword(s):  
Solar Cells ◽  
Spectral Response ◽  
Response Analysis ◽  
Current Collection

Photocurrent and Spectral Response Analysis of a-SiC:H Pinip and Pinpin Photodiodes

2009 ◽  
Vol 9 (7) ◽  
pp. 4254-4258
Author(s):  
A. Fantoni ◽  
M. Vieira ◽  
Y. Vygranenko ◽  
M. Fernandes ◽  
P. Louro
Keyword(s):  
Spectral Response ◽  
Response Analysis

High efficiency CuInSe2–(CdZn)S solar cells: fabrication, results, and analysis

1989 ◽  
Vol 67 (4) ◽  
pp. 420-424
Author(s):  
S. Damaskinos ◽  
J. E. Phillips ◽  
M. Roy ◽  
R. W. Birkmire
Keyword(s):  
Physical Vapor Deposition ◽  
High Efficiency ◽  
Spectral Response ◽  
Response Analysis ◽  
Current Transport ◽  
Recombination Mechanism ◽  
Interface Recombination ◽  
Current Voltage ◽  
Solar Application ◽  
Diode Current

The CuInSe2 thin films for solar application are grown by physical vapor deposition in a standard evaporation system. Indium-doped high conductivity (CdZn)S is evaporated onto the CuInSe2 to form the junction. The CuInSe2–(CdZn)S devices require air heat treatments to achieve the highest efficiency. High-efficiency small-area devices exceeding 11% (87.5 mW/cm2, ELH, T = 32 °C) have been fabricated this way. The behavior of the devices cannot be described as a classical heterojunction dominated by interface recombination. Instead, current–voltage and spectral-response analysis show that the diode current transport is dominated by a Shockley–Read type of recombination model, with space–charge being the dominant recombination mechanism via midgap states, with an estimated concentration of 1014 cm−3.

scholarly journals Basin effects and limitations of 1D site response analysis from 2D numerical models of the Thorndon basin

2021 ◽  
Vol 54 (1) ◽  
pp. 21-30
Author(s):  
Christopher R McGann ◽  
Brendon Bradley ◽  
Liam Wotherspoon ◽  
Robin Lee
Keyword(s):  
Shear Wave ◽  
Numerical Models ◽  
Site Response ◽  
Spectral Response ◽  
Strong Motion ◽  
Response Analysis ◽  
Basin Effects ◽  
Modelling Studies ◽  
Vertically Propagating ◽  
Propagating Shear

Plane strain (2D) finite element models are used to examine factors contributing to basin effects observed for multiple seismic events at sites in the Thorndon basin of Wellington, New Zealand. The models consider linear elastic soil and rock response when subjected to vertically-propagating shear waves. Depth-dependent shear wave velocities are considered in the soil layers, and the effects of random variations of soil velocity within layers are modelled. Various rock shear wave velocity configurations are considered to evaluate their effect on the modelled surficial response. It is shown that these simple 2D models are able to capture basin reverberations and compare more favourably to observations from strong motion recordings than conventional 1D site response models. It is also shown that consideration of a horizontal impedance contrast across the Wellington Fault affects spectral response and amplification at longer periods, suggesting the importance of this feature in future ground motion modelling studies in the Wellington region.

scholarly journals Comparative Analysis Study Of ATC-40 and SNI 1726-2012 Guidelines for Beam Structure Performance and Column Trans Studio Apartments Applications Using Dynamic Response Spectrum Analysis Methods

2019 ◽  
Vol 1 (1) ◽  
pp. 46-55
Author(s):  
Agyanata Tua Munthe ◽  
Abdul Gafur
Keyword(s):  
Dynamic Analysis ◽  
Response Spectrum ◽  
Spectral Response ◽  
Response Analysis ◽  
Building Structures ◽  
Base Shear ◽  
Maximum Displacement ◽  
Response Dynamic ◽  
Earthquake Force ◽  
Dynamic Time

The earthquake that often hit Indonesia caused thousands of lives and caused damage to buildings. These earthquakes often occur because Indonesia is in two regions, namely the Pacific earthquake path (Circum Pacific Earthquake Belt) and the Asian earthquake lane (Trans Asiatic Earthquake Belt). Earthquake disasters cause damage to building structures. When an earthquake occurs, it is expected that the building can accept earthquake force at a certain level without significant damage to its structure. In general, earthquake analysis is divided into two major parts, namely static earthquake analysis and dynamic earthquake analysis. In buildings that are very high, irregular, multilevel, and buildings that require enormous accuracy are used dynamic analysis planning, which consists of a variety of spectral response analysis and dynamic time response dynamic analysis. This study aims to determine the building's security in terms of displacement, drift, and base shear. The method used is a dynamic analysis of the response spectrum using the ETABS program. The maximum total drift in the X direction is 0.0200475 m and in the Y direction is 0.020405 m, so the building is safe against ultimate boundary performance (0.02h) and service boundary performance {(0.03 / R) x h}. So that the displacement in the building does not exceed the maximum displacement, the building is safe from earthquake plans.

scholarly journals A Nonstationary Mathematical Model for Acceleration Time Series

2021 ◽  
Vol 8 (2) ◽  
pp. 246-252
Author(s):  
Tahar Brahimi ◽  
Tahar Smain
Keyword(s):  
Time Series ◽  
Energy Demand ◽  
Spectral Response ◽  
Qualitative Description ◽  
Response Analysis ◽  
Model Parameters ◽  
Ductility Demand ◽  
Displacement Ductility ◽  
Acceleration Time ◽  
Hysteretic Energy

The choice of nonstationary stochastic models for the study is fully justified by the limitation of acceleration time series number. The three acceleration time series under consideration are used to generate a new, artificial series of ten per historical one using autoregressive moving average model. Subsequently, the average of nonlinear is utilized for the ten acceleration time series in order to obtain the spectral response of a system with single degree of freedom. Modeling of acceleration time series involves critical estimation of metrics that characterize nonstationary acceleration time series. Thus, for the stiffness degrading systems and bilinear systems, the metrics of hysteretic energy demand and displacement ductility demand during displacement are used. The applicability of artificially generated acceleration time series for the qualitative description of information was shown. More specifically, ARMA (2,2) showed the best results in the study for three accelerated time series through nonlinear response analysis. In addition, as a result, normalized hysteretic energy demand, empirically valid displacement ductility relationships, and model parameters were proposed.

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