The Experts below are selected from a list of 5202 Experts worldwide ranked by ideXlab platform
Thomas Zimmer - One of the best experts on this subject based on the ideXlab platform.
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Thermal Penetration Depth Analysis and Impact of the BEOL Metals on the Thermal Impedance of SiGe HBTs
IEEE Electron Device Letters, 2017Co-Authors: Rosario D’esposito, Suresh Balanethiram, Jean-luc Battaglia, Sébastien Frégonèse, Thomas ZimmerAbstract:In this letter, we present a detailed investigation on how dynamic Thermal phenomena take place in state of-the-art SiGe HBTs when excited by sinusoidal power dissipation. To give a better insight into the mechanisms leading to the Thermal impedance (Zth) decay, we introduce the concept of Thermal Penetration Depth; then, with the help of 3-D Thermal simulations, we illustrate its effect on the spatial distribution of the temperature variations within the transistor structure, according to the frequency of operation. In order to experimentally analyze the impact on a real device, dedicated HBT structures are designed; they consist of multi-finger SiGe HBTs realized in B55 technology from STMicroelectronics,for which modifications are made in the back-end-of-line (BEOL) metallization or in the transistor layout, increasing its deep trench isolation enclosed area. For these transistors, Zth measurements are carried out in the frequency range 10kHz-1GHz; the results show that the metal connections configuration in the BEOL or layout modifications can considerably impact the Zth decay at low frequencies. An identical Zth trend is instead measured above 1-2 MHz, demonstrating that at higher frequencies just the region close to the heat source is concerned by dynamic Thermal phenomena.
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Thermal Penetration Depth Analysis and Impact of the BEOL Metals on the Thermal Impedance of SiGe HBTs
IEEE Electron Device Letters, 2017Co-Authors: Rosario D'esposito, Suresh Balanethiram, Jean-luc Battaglia, Sébastien Frégonèse, Thomas ZimmerAbstract:In this letter, we present a detailed investigation on how dynamic Thermal phenomena take place in state-of-the-art SiGe HBTs when excited by sinusoidal power dissipation. To give a better insight into the mechanisms leading to the Thermal impedance ( $\text{Z}_{{\textsf {th}}})$ decay, we introduce the concept of Thermal Penetration Depth; then, with the help of 3-D Thermal simulations, we illustrate its effect on the spatial distribution of the temperature variations within the transistor structure, according to the frequency of operation. In order to experimentally analyze the impact on a real device, dedicated HBT structures are designed; they consist of multi-finger SiGe HBTs realized in B55 technology from STMicroelectronics, for which modifications are made in the back-end-of-line (BEOL) metallization or in the transistor layout, increasing its deep trench isolation enclosed area. For these transistors, $\text{Z}_{{\textsf {th}}}$ measurements are carried out in the frequency range 10kHz–1GHz; the results show that the metal connections configuration in the BEOL or layout modifications can considerably impact the $\text{Z}_{{\textsf {th}}}$ decay at low frequencies. An identical $\text{Z}_{{\textsf {th}}}$ trend is instead measured above 1–2 MHz, demonstrating that at higher frequencies just the region close to the heat source is concerned by dynamic Thermal phenomena.
Israel Gannot - One of the best experts on this subject based on the ideXlab platform.
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monitoring litt Thermal Penetration Depth using real time analysis of backscattered light
Journal of Biophotonics, 2014Co-Authors: Ranit Shacham, Amir H. Gandjbakhche, Idan Steinberg, Israel GannotAbstract:Real-time monitoring of the Thermal Penetration Depth (TPD) is essential in various clinical procedures, such as Laser Interstitial Thermal Therapy (LITT). MRI is commonly used to this end, though bulky and expensive. In this paper, we present an alternative novel method for an optical feedback system based on changes in the diffused reflection from the tissue during treatment. Monte-Carlo simulation was used to deduce the relations between the backscattered pattern and the TPD. Several methods of image analysis are developed for TPD estimation. Each yields a set of parameters which are linearly dependent on the TPD. In order to test these experimentally, tissue samples were monitored in-vitro during treatment at multiple wavelengths. The SNR and coefficient of determination were used to compare the various methods and wavelengths and to determine the preferred method. Such system and algorithms may be used for real-time in-vivo control during laser thermotherapy and other clinical procedures. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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Monitoring LITT Thermal Penetration Depth using real‐time analysis of backscattered light
Journal of Biophotonics, 2012Co-Authors: Ranit Shacham, Amir H. Gandjbakhche, Idan Steinberg, Israel GannotAbstract:Real-time monitoring of the Thermal Penetration Depth (TPD) is essential in various clinical procedures, such as Laser Interstitial Thermal Therapy (LITT). MRI is commonly used to this end, though bulky and expensive. In this paper, we present an alternative novel method for an optical feedback system based on changes in the diffused reflection from the tissue during treatment. Monte-Carlo simulation was used to deduce the relations between the backscattered pattern and the TPD. Several methods of image analysis are developed for TPD estimation. Each yields a set of parameters which are linearly dependent on the TPD. In order to test these experimentally, tissue samples were monitored in-vitro during treatment at multiple wavelengths. The SNR and coefficient of determination were used to compare the various methods and wavelengths and to determine the preferred method. Such system and algorithms may be used for real-time in-vivo control during laser thermotherapy and other clinical procedures. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Qin Zhao - One of the best experts on this subject based on the ideXlab platform.
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thermo mechanical properties of compaction molded cement based composite containing a high volume fraction of phase change material for Thermal energy storage
Composites Part A-applied Science and Manufacturing, 2020Co-Authors: Guochen Sang, Yangkai Zhang, Xiaoyun Du, Qin ZhaoAbstract:Abstract This study presents a novel compaction molded composite of sulphoaluminate cement-based Thermal energy storage mortar (SCTESM) containing shape stabilized phase change materials (SSPCM) up to 25.9 wt%. A series of tests were conducted to investigate the thermo-mechanical properties of SCTESM. The results show that the Thermal conductivity of the compaction molded SCTESM is about 60% higher than that of casting molded one. A mathematical model for Thermal conductivity prediction was proposed with a maximum relative error of 5.69%. Furthermore, the Thermal Penetration Depth of SCTESMs was also analyzed, and the Thermal Penetration Depth of the compaction molded samples was over 30% higher than that of casting molded sample of same SSPCM dosage. The mechanical strength determination revealed that compaction molding method can increase the 28-day compressive strength and flexural strength of SCTESM by 28.0% and 40.0% than that of casting molded one with the same SSPCM dosage.
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thermo mechanical properties of compaction molded cement based composite containing a high mass fraction of phase change material for Thermal energy storage
Composites Part A-applied Science and Manufacturing, 2020Co-Authors: Guochen Sang, Yangkai Zhang, Min Fan, Hongzhi Cui, Xiaoling Cui, Yiyun Zhu, Qin ZhaoAbstract:Abstract This study presents a novel compaction molded composite of sulphoaluminate cement-based Thermal energy storage mortar (SCTESM) containing shape stabilized phase change materials (SSPCM) up to 25.9 wt%. A series of tests were conducted to investigate the thermo-mechanical properties of SCTESM. The results show that the Thermal conductivity of the compaction molded SCTESM is about 60% higher than that of casting molded one. A mathematical model for Thermal conductivity prediction was proposed with a maximum relative error of 5.69%. Furthermore, the Thermal Penetration Depth of SCTESMs was also analyzed, and the Thermal Penetration Depth of the compaction molded samples was over 30% higher than that of casting molded sample of same SSPCM dosage. The mechanical strength determination revealed that compaction molding method can increase the 28-day compressive strength and flexural strength of SCTESM by 28.0% and 40.0% than that of casting molded one with the same SSPCM dosage.
Davood Domiri Ganji - One of the best experts on this subject based on the ideXlab platform.
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Thermal Penetration Depth enhancement in latent heat Thermal energy storage system in the presence of heat pipe based on both charging and discharging processes
Energy Conversion and Management, 2017Co-Authors: Sina Lohrasbi, Mofid Gorji-bandpy, Davood Domiri GanjiAbstract:Abstract Latent Heat Thermal Energy Storage Systems (LHTESS) have attracted increasing attentions in recent years. In these systems, energy storage-retrieval are achieved during solid-liquid phase change of Phase Change Materials (PCM). Because of low Thermal conductivity of PCMs, energy storage and retrieval cannot be achieved in desired time duration. In the present study, a novel fin configuration is optimized based on both charging and discharging processes using Response Surface Method (RSM). Following this, the optimum fin array is attached to heat pipe to improve its ability in increasing Thermal Penetration Depth into the PCM. In the subsequent stage, the system with optimum finned heat pipe is compared to other systems in the presence of common fin arrays. The parameter of maximum energy storage capacity of the system is implemented quantitatively in the optimization procedure, and the efficiency of using this parameter as one of the objectives of LHTESS design is examined, which is proposed as the novelty here. Results indicate that attaching fin of suitable configuration to the heat pipe enhances its performance in increasing Thermal Penetration Depth into the PCM. Moreover, it is indicated that choosing maximum energy storage capacity as one of the objectives of optimization procedure for LHTESS performance evaluation leads to efficient design.
Ranit Shacham - One of the best experts on this subject based on the ideXlab platform.
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monitoring litt Thermal Penetration Depth using real time analysis of backscattered light
Journal of Biophotonics, 2014Co-Authors: Ranit Shacham, Amir H. Gandjbakhche, Idan Steinberg, Israel GannotAbstract:Real-time monitoring of the Thermal Penetration Depth (TPD) is essential in various clinical procedures, such as Laser Interstitial Thermal Therapy (LITT). MRI is commonly used to this end, though bulky and expensive. In this paper, we present an alternative novel method for an optical feedback system based on changes in the diffused reflection from the tissue during treatment. Monte-Carlo simulation was used to deduce the relations between the backscattered pattern and the TPD. Several methods of image analysis are developed for TPD estimation. Each yields a set of parameters which are linearly dependent on the TPD. In order to test these experimentally, tissue samples were monitored in-vitro during treatment at multiple wavelengths. The SNR and coefficient of determination were used to compare the various methods and wavelengths and to determine the preferred method. Such system and algorithms may be used for real-time in-vivo control during laser thermotherapy and other clinical procedures. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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Monitoring LITT Thermal Penetration Depth using real‐time analysis of backscattered light
Journal of Biophotonics, 2012Co-Authors: Ranit Shacham, Amir H. Gandjbakhche, Idan Steinberg, Israel GannotAbstract:Real-time monitoring of the Thermal Penetration Depth (TPD) is essential in various clinical procedures, such as Laser Interstitial Thermal Therapy (LITT). MRI is commonly used to this end, though bulky and expensive. In this paper, we present an alternative novel method for an optical feedback system based on changes in the diffused reflection from the tissue during treatment. Monte-Carlo simulation was used to deduce the relations between the backscattered pattern and the TPD. Several methods of image analysis are developed for TPD estimation. Each yields a set of parameters which are linearly dependent on the TPD. In order to test these experimentally, tissue samples were monitored in-vitro during treatment at multiple wavelengths. The SNR and coefficient of determination were used to compare the various methods and wavelengths and to determine the preferred method. Such system and algorithms may be used for real-time in-vivo control during laser thermotherapy and other clinical procedures. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
