title: Design study of a thermocouple power sensor as a monolithic fin-line

authors: Jones, Mark Hedley

subjects: electronics

abstract: Making traceable power measurements above 110 GHz using current measurement technologies is challenging. We investigate a design of power sensor consisting of a thermocouple-based integrated circuit (IC) mounted as a finline component in WR-6 waveguide. The design is original in that it contains an antenna, terminating resistor and thermocouples on-chip. We detail the design and report results from simulations and measurements made on a two-port 16:1 scale model. Our design of scale model provides both insertion and reflection loss measurements. Electromagnetic simulation and easily-calibrated model measurements confirm that the short antenna fins feasible on a monolithic microwave integrated circuit (MMIC) can achieve acceptable specifications. The design proves to be relatively insensitive to the value of the terminating resistance or the size of the antenna fins.

text: Design study of a thermocouple power sensor as a monolithic fin-line Making traceable power measurements above 110 GHz using current measurement technologies is challenging. We investigate a design of power sensor consisting of a thermocouple-based integrated circuit (IC) mounted as a finline component in WR-6 waveguide. The design is original in that it contains an antenna, terminating resistor and thermocouples on-chip. We detail the design and report results from simulations and measurements made on a two-port 16:1 scale model. Our design of scale model provides both insertion and reflection loss measurements. Electromagnetic simulation and easily-calibrated model measurements confirm that the short antenna fins feasible on a monolithic microwave integrated circuit (MMIC) can achieve acceptable specifications. The design proves to be relatively insensitive to the value of the terminating resistance or the size of the antenna fins.

year: 2011

title: Estimation of the motor threshold for near-rectangular stimuli using the hodgkin-huxley model

authors: Sorkhabi, Majid Memarian

subjects: Science & Technology

abstract: The motor threshold measurement is a standard in preintervention probing in TMS experiments. We aim to predict the motor threshold for near-rectangular stimuli to efficiently determine the motor threshold size before any experiments take place. Estimating the behavior of large-scale networks requires dynamically accurate and efficient modeling. We utilized a Hodgkin–Huxley (HH) type model to evaluate motor threshold values and computationally validated its function with known true threshold data from 50 participants trials from state-of-the-art published datasets. For monophasic, bidirectional, and unidirectional rectangular stimuli in posterior-anterior or anterior-posterior directions as generated by the cTMS device, computational modeling of the HH model captured the experimentally measured population-averaged motor threshold values at high precision (maximum error ≤ 8%). )e convergence of our biophysically based modeling study with experimental data in humans reveals that the effect of the stimulus shape is strongly correlated with the activation kinetics of the voltage-gated ion channels. The proposed method can reliably predict motor threshold size using the conductance-based neuronal models and could therefore be embedded in new generation neurostimulators. Advancements in neural modeling will make it possible to enhance treatment procedures by reducing the number of delivered magnetic stimuli to participants.

text: Estimation of the motor threshold for near-rectangular stimuli using the hodgkin-huxley model The motor threshold measurement is a standard in preintervention probing in TMS experiments. We aim to predict the motor threshold for near-rectangular stimuli to efficiently determine the motor threshold size before any experiments take place. Estimating the behavior of large-scale networks requires dynamically accurate and efficient modeling. We utilized a Hodgkin–Huxley (HH) type model to evaluate motor threshold values and computationally validated its function with known true threshold data from 50 participants trials from state-of-the-art published datasets. For monophasic, bidirectional, and unidirectional rectangular stimuli in posterior-anterior or anterior-posterior directions as generated by the cTMS device, computational modeling of the HH model captured the experimentally measured population-averaged motor threshold values at high precision (maximum error ≤ 8%). )e convergence of our biophysically based modeling study with experimental data in humans reveals that the effect of the stimulus shape is strongly correlated with the activation kinetics of the voltage-gated ion channels. The proposed method can reliably predict motor threshold size using the conductance-based neuronal models and could therefore be embedded in new generation neurostimulators. Advancements in neural modeling will make it possible to enhance treatment procedures by reducing the number of delivered magnetic stimuli to participants.

year: 2021

title: Te Ira Atua: The spiritual spark of the child

authors: Rameka, Lesley Kay

abstract: “E ai ki tā te Māori he atua tonu kei roto i te mokopuna ina whānau mai ana ia ki tēnei ao” (Ministry of Education, 1996, p. 35). This quote is from the New Zealand Ministry of Education’s early childhood curriculum policy statement, Te Whāriki: He Whāriki Matauranga mo ngā Mokopuna o Aotearoa/Early Childhood Curriculum (Ministry of Education, 1996). It speaks of the godliness or spiritual essence each child inherits from their ancestors when they are born (Early Childhood Development, 1999; Reedy, 2003). From a traditional Māori perspective, not only is the child endowed with spiritual potential or a divine spirit, but the world the child is born into is also endowed with spiritual influences.

text: Te Ira Atua: The spiritual spark of the child “E ai ki tā te Māori he atua tonu kei roto i te mokopuna ina whānau mai ana ia ki tēnei ao” (Ministry of Education, 1996, p. 35). This quote is from the New Zealand Ministry of Education’s early childhood curriculum policy statement, Te Whāriki: He Whāriki Matauranga mo ngā Mokopuna o Aotearoa/Early Childhood Curriculum (Ministry of Education, 1996). It speaks of the godliness or spiritual essence each child inherits from their ancestors when they are born (Early Childhood Development, 1999; Reedy, 2003). From a traditional Māori perspective, not only is the child endowed with spiritual potential or a divine spirit, but the world the child is born into is also endowed with spiritual influences.

year: 2015