scholarly journals CCD Imagers by Enhanced UV Sensitivity for Industrial and Scientific Applications

1995 ◽  
Vol 167 ◽  
pp. 323-324
Author(s):  
G. I. Vishnevsky ◽  
M. G. Vydrevich ◽  
L. Yu. Lazovsky ◽  
V. G. Kossov ◽  
S. S. Tatautshchikov
Keyword(s):  
Quantum Efficiency ◽  
Image Sensors ◽  
Fabrication Process ◽  
Scientific Applications ◽  
Uv Sensitivity ◽  
Ccd Array ◽  
Three Phase ◽  
Common Concept ◽  
The Common ◽  
Photosensitive Cell

A family of virtual phase (VP) CCD array image sensors for various industrial and scientific applications has been designed, fabricated and tested. All share the common concept of a “2.5-phase” photosensitive cell, combining the advantages of known “1.5-phase” VP devices (increased quantum efficiency, especially in the UV, and radiation hardness) with the simpler fabrication process and extended functionality of three-phase devices.

scholarly journals Opposite Triangle Carrier with SVPWM for Common-Mode Voltage Reduction in Dual Three Phase Motor Drives

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 282
Author(s):  
Seon-Ik Hwang ◽  
Jang-Mok Kim
Keyword(s):  
Electromagnetic Interference ◽  
Pulse Width Modulation ◽  
Motor Drives ◽  
Common Mode ◽  
Pwm Inverter ◽  
Common Mode Voltage ◽  
Voltage Vector ◽  
Three Phase ◽  
The Common ◽  
Zero Voltage

The common-mode voltage (CMV) generated by the switching operation of the pulse width modulation (PWM) inverter leads to bearing failure and electromagnetic interference (EMI) noises. To reduce the CMV, it is necessary to reduce the magnitude of dv/dt and change the frequency of the CMV. In this paper, the range of the CMV is reduced by using opposite triangle carrier for ABC and XYZ winding group, and the change in frequency in the CMV is reduced by equalizing the dwell time of the zero voltage vector on ABC and XYZ winding group of dual three phase motor.

Three-Phase and Five-Phase Motor Windings Common Point Potential Ripple with Respect to the Converter Zero Termina

Vestnik MEI ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 51-59
Author(s):  
Vladimir M. Tereshkin ◽  
◽  
Irshat L. Aitov ◽  
Dmitriy A. Grishin ◽  
Vyacheslav V. Tereshkin ◽  
...  
Keyword(s):  
Amplitude Modulation ◽  
Zero Point ◽  
Space Time ◽  
Common Point ◽  
Point Potential ◽  
Voltage Vector ◽  
Three Phase ◽  
Ripple Amplitude ◽  
The Common ◽  
Rotating Field

The aim of the study is to determine the parameters characterizing the ripple of a motor's three- and five-phase windings common point potentials (for the star winding connection diagram) with respect to the converter zero point. One of the reserves for decreasing electromagnetically induced vibration of an electric motor with a rotating field is to increase the number of working winding phases. The study subject is a five-phase motor winding connected to a bridge converter, namely, its ability to reduce electromagnetically induced vibration in comparison with that in using a three-phase winding. The common point potential ripple parameters are studied, and an approach is proposed to estimating the amplitude modulation of the space-time voltage vector of three- and five-phase windings under the influence of the common point potential ripple with respect to the converter zero point. Theoretical studies were carried out using the Fourier series expansion method and vector analysis methods. To confirm the theoretical results, experimental studies of the prototypes of three-phase and five-phase synchronous motors with inductors made on the basis of permanent magnets were carried out. The main results have shown the following. With increasing the number of phases of the rotating field motor working winding connected to a bridge converter, the common point potential ripple amplitude with respect to the converter zero point decreases, and the ripple frequency increases. The product of ripple amplitude by frequency remains unchanged. It is assumed that the common point potential ripple of the motor multiphase winding with respect to the converter zero terminal results in the amplitude modulation of the space-time voltage vector. With increasing the number of winding phases, the modulation amplitude decreases, and the modulation frequency increases. A five-phase motor has a lower level of the working winding common point potential ripple with respect to the converter zero point in comparison with a three-phase motor. Thus, it can be assumed that there will be a lower level of electromagnetically induced vibration in using a simple converter operation algorithm. The obtained results can be used in designing electric traction systems with vector control on the basis of multiphase motors. With increasing the number of phases, the common point potential ripple amplitude in a multiphase winding with respect to the converter zero point decreases, and the ripple frequency increases. Thus, the common point potential ripple amplitude in a five-phase winding is 5/3 times less than that in a three-phase winding, and the ripple frequency increases by 5/3 times, respectively. With increasing the number of working winding phases, the amplitude modulation of the resulting space-time voltage vector decreases. This circumstance has a positive effect on decreasing the electromagnetically induced vibration.

Modeling and measurements of MTF and quantum efficiency in CCD and CMOS image sensors

2010 ◽  
Author(s):  
Ibrahima Djité ◽  
Pierre Magnan ◽  
Magali Estribeau ◽  
Guy Rolland ◽  
Sophie Petit ◽  
...  
Keyword(s):  
Quantum Efficiency ◽  
Image Sensors ◽  
Cmos Image Sensors

Strength of Surface Micromachined Diaphragms

1998 ◽  
Vol 518 ◽  
Author(s):  
Xing Yang ◽  
Frances M. Siu ◽  
Yu-Chong Tai
Keyword(s):  
Boundary Condition ◽  
Silicon Nitride ◽  
Boundary Conditions ◽  
Fabrication Process ◽  
Surface Micromachining ◽  
Fabrication Technique ◽  
Different Boundary Conditions ◽  
The Common

AbstractThis paper presents the study of the strength of surface micromachined diaphragms. It is found that the diaphragm strength strongly depends on the diaphragm boundary conditions. A new fabrication technique which does not change the mask and fabrication process is proposed to improve the common step-up boundary condition. Test diaphragms with diameters from 200 µm to 800 µm and three different boundary conditions have been fabricated using silicon nitride/PSG and silicon nitride/polysilicon surface micromachining processes. Experimentally, it is found that the strength of the diaphragms is significantly improved with the new boundary conditions. The application of this technique to other surface micromachined structures is also described.

Reframing “building back better” for post-disaster housing design: a community perspective

2016 ◽  
Vol 7 (4) ◽  
pp. 344-360 ◽  
Author(s):  
Yenny Rahmayati
Keyword(s):  
Qualitative Methodology ◽  
Way Of Life ◽  
Content Type ◽  
Housing Design ◽  
Disaster Survivors ◽  
Common Concept ◽  
The Common ◽  
Housing Reconstruction ◽  
Post Disaster

Purpose This study aims to reframe the common concept of post-disaster reconstruction “building back better”, especially in the context of post-disaster housing design. Design/methodology/approach An Aceh post-tsunami housing reconstruction project is used as a case study with qualitative methodology through in-depth interviews of selected respondents. Findings The study findings have shown that the term “building back better” is not a familiar term for housing recipients. Whichever different personal background post-disaster survivors come from, whether they are housewife, civil servant, fisherman, university student, businessman or a professional, none have ever heard this phrase. All found it hard to understand the term. This study argues that the “building back better” concept is good in policy but not working in practice. As a result, housing recipients not only were dissatisfied with their new houses but also found that the new housing configurations profoundly altered their traditional way of life. In light of these findings, the paper argues that the concept of “building back better” needs to be reframed to take account of the cultural individual and communal needs and wants of post-disaster survivors. Research limitations/implications This study discusses only one aspect of post-disaster reconstruction that is the design of housing reconstruction. Practical implications Results from this study provide a practical contribution for reconstruction actors especially designers, architects and planners. It helps them to reconsider the common concepts they have used for post-disaster reconstruction processes particularly in designing housing reconstruction projects. Originality/value This study focuses on the question of how tsunami survivors in Aceh reacted to the design of their new post-tsunami houses and what they had done themselves to make their homes a better and nicer place to live within their own cultural needs. This study also sought to understand what motivated the opinions the respondents had about the design of housing reconstruction after the tsunami in Aceh generally. In addition, the study investigated whether survivors knew the phrase and the credo of “building back better” in a post-disaster context.

Improved Electrical Properties of Ga2O3:Sn/CIGS Hetero-Junction Photoconductor

2014 ◽  
Vol 1635 ◽  
pp. 83-88
Author(s):  
Kenji Kikuchi ◽  
Shigeyuki Imura ◽  
Kazunori Miyakawa ◽  
Hiroshi Ohtake ◽  
Misao Kubota ◽  
...  
Keyword(s):  
Thin Film ◽  
Quantum Efficiency ◽  
Repetition Rate ◽  
Dark Current ◽  
Carrier Density ◽  
High Efficiency ◽  
Visible Region ◽  
Laser Frequency ◽  
Image Sensors ◽  
High Quantum Efficiency

ABSTRACTWe examined the potential application of CuIn1-xGaxSe1-ySy (CIGS) film for visible light image sensors. CIGS chalcopyrite semiconductors, which are representative of high efficiency thin film solar cells, have both a high absorption coefficient and high quantum efficiency. However, their dark current is too high for image sensors. In this study, we applied gallium oxide (Ga2O3) as a hole-blocking layer for CIGS thin film to reduce the dark current. The dark current of this hetero-junction was 10-9 A/cm2 at less than 7 V. Moreover, an avalanche multiplication phenomenon was observed at an applied voltage of over 8 V. However, this structure had sensitivity only in the ultraviolet light region due to the much lower carrier density of the Ga2O3 layer. We therefore used a tin-doped Ga2O3 (Ga2O3:Sn) layer deposited by pulsed laser deposition (PLD) for the n-type layer to increase the carrier density. The sensitivity of the visible region was observed in the Ga2O3:Sn/CIGS hetero-junction. We also investigated the influence of the laser frequency of the PLD on the transmittance of Ga2O3:Sn and the quantum efficiency of this hetero-junction. Ga2O3:Sn film deposited at a 0.1-Hz laser repetition rate had higher transmittance than at a 10-Hz repetition rate. The Ga2O3:Sn/CIGS hetero-junction also had a higher quantum efficiency with the lower rate (50%) than with the higher rate (30%).

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