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An artificial neural network (ANN) based tunable automated standalone RF sensor system is proposed to realize an improved sensing module involving a quite accurate solution of the non-linear inverse characterization problem. The presented tunable sensor system is quite novel as it alleviates the need for any active tuning circuitry. Moreover, the proposed unified design topology facilitates a relatively higher tuning range (1900 MHz) than that of the earlier reported (580 MHz) capacitor-based tunable complementary split-ring resonator (CSRR). The higher tuning range of structures resulted from the improved design configuration comprising a modified CSRR design coupled with a modified microstrip line. The obtained dielectric sensitivity is ∼8.8%. The numerically generated S-parameters of various dielectric samples are used here as a training dataset for the ANN, which is trained using the Levenberg–Marquardt backpropagation algorithm in combination with the Bayesian regularization. Finally, several standard test samples at different unloaded tuned frequencies are measured to record the corresponding resonant frequency and magnitude of the S-parameter in order to process them using the proposed ANN-based sensor system. It is found that the developed ANN-based sensor system provides a reasonably accurate value of the extracted complex permittivity over the frequency range under consideration, which basically removes the need for designing multiple resonant structures unlikely to the conventional resonant sensors. [ABSTRACT FROM AUTHOR]

An artificial neural network (ANN) based frequency controlled automated RF sensor system for the characterization of dispersive liquids is presented. The frequency of the designed structure is electronically controlled by varying the applied reverse-biased voltage to the complementary split ring resonator (CSRR) attached varactor diode. A hybrid modelling approach has mainly been devised to account for the effects of biasing circuitry and the parasitic elements. The designed RF sensor can provide a relatively higher tuning bandwidth (800 MHz) for applied DC biasing voltage of 0–25 V. The proposed sensor system employs an artificially intelligent feed-forward neural network architecture, which is trained by the Levenberg–Marquardt training algorithm for the complex permittivity estimation in the designated frequency band with reasonable accuracy. It employs the Bayesian Regularization for better input–output correlation and system performance. The ANN based characterization algorithm is integrated with a graphical user interface (GUI) and implemented using MATLAB. [ABSTRACT FROM AUTHOR]

We are proud to bring to you an issue focused on a pertinent topic-new mobility. The term new mobility was coined to represent four pivotal technologies that will change how we move not only ourselves but also our cargo: connected cars, autonomy, shared mobility, and electrification. The acronyms CASE or ACES are often used to convey these traits that new mobility entails. [ABSTRACT FROM AUTHOR]

The Manual Dexterity Test (MDT) was originally developed in the 1940s as part of the American Dental Association's Dental Aptitude Test to assist in reducing high attrition rates in U.S. dental schools. The Perceptual Motor Ability Test (PMAT) replaced the MDT in 1972 in the U.S., but the MDT continues to be available in Canada. The MDT was originally developed to be used as a screening tool to eliminate those applicants who demonstrated poor psychomotor skills, and it was very effective in doing so. The MDT has been subsequently criticized for not being an effective predictor of performance in dental school. The aim of this study was to determine the level of correlation between MDT scores and psychomotor skills assessment scores in preclinical psychomotor skills courses in the DDS program at Dalhousie University. Three key preclinical psychomotor skills courses were identified, and their course coordinators were asked to identify students who had been accepted into the program but had extremely weak psychomotor skills. Those students' psychomotor skills scores were then compared to their MDT scores. The results showed that when the student had an MDT score of 10 or less, there was high sensitivity (though low specificity) in identifying students with extremely weak psychomotor skills. Those students with MDT scores of 11 or above were unlikely to have difficulties in psychomotor skills courses. These findings support the MDT's use as a screening tool in the admissions process and a minimum cut-off score of 11 out of 30. [ABSTRACT FROM AUTHOR]

Background. The authors evaluated the effectiveness of using a patient simulator (MARC Patient Simulator [MARC PS], BlueLight analytics, Halifax, Nova Scotia, Canada), to instruct dental students (DS) on how to deliver energy optimally to a restoration from a curing light. Five months later, the authors evaluated the retention of the instruction provided to the DS. Methods. Toward the end of the DS' first year of dental education, the authors evaluated the light- curing techniques of one-half of the class of first-year DS (Group 1) before and after receiving instruction by means of the patient simulator. Five months later, they retested DS in Group 1 and tested the remaining first-year DS who were then second-year DS and who had received no instruction by means of the patient simulator (Group 2). They gave DS in Group 1 and Group 2 MARC PS instruction and retested them. The authors also the tested fourth-year DS (Group 3) and dentists (Group 4) by using the MARC PS before giving any instruction by means of the MARC PS. Results. The results of one-way analysis of variance (ANOVA) showed that there were no significant differences in the ability of dentists and DS to light cure a simulated restoration before they received instruction by means of the patient simulator (P = .26). The results of two-way ANOVA and Fisher protected least significant difference tests showed that after receiving instruction by means of the patient simulator, DS delivered significantly more energy to a simulated restoration, and this skill was retained. There were no significant differences between DS in Group 1 and Group 2 after they had received instruction by means of the patient simulator. Conclusions. The abilities of dentists and DS to light cure a simulated restoration were not significantly different. Hands-on teaching using a patient simulator enhanced the ability of DS to use a curing light. This skill was retained for at least five months. Practical Implications. The education provided to dentists and DS is insufficient to teach them how to deliver the optimum amount of energy from a curing light. Better teaching and understanding of the importance of light curing is required. [ABSTRACT FROM AUTHOR]

Objective: To measure the light energy that dental students delivered to a simulated Class I restoration before training, immediately after training and 4 months after training. Methods: Thirty-eight (38) dental students used a single light-emitting diode curing light (SmartLite iQ2, Dentsply) to cure, for 10 seconds, a simulated Class I restoration positioned in the Managing Accurate Resin Curing - Patient Simulator (BlueLight analytics inc.). The students then attended an instructional lecture and received individualized instruction on optimizing their lightcuring technique. The students were retested immediately after instruction and again 4 months later (without further instruction). The irradiance and energy delivered during light-curing were calculated for each student at all 3 time points. Mean values were calculated and compared. Results: Before instruction, the students delivered between 0.1 and 7.2 J/cm² of energy (mean ± standard deviation [SD] 4.1 ± 1.7 J/cm²). After instruction, the same students delivered between 5.8 and 7.5 J/cm² of energy (mean ± SD 6.7 ± 0.4 J/cm²). Analysis of variance and Fisher's Protected Least Significant Difference tests showed that instruction with the patient simulator led to a significant improvement in the amount of energy delivered and that the students retained this information. When retested 4 months later, the students delivered between 4.2 and 7.9 J/cm² of energy (mean ± SD 6.1 ±1.1 J/cm²). Although this was less energy than immediately after instruction, the decline was not significant (p = 0.44). Conclusions: Provision of immediate feedback on light-curing technique and instruction on how to avoid mistakes led to a significant and lasting improvement in the amount of energy delivered by the students. [ABSTRACT FROM AUTHOR]

The hot carrier and ionizing radiation responses of 45-nm SOI RF nMOSFETs are investigated. Devices with “tight” source/drain (S/D) contact spacing have improved RF performance but degraded hot carrier reliability and radiation tolerance. Devices with “loose” gate finger-to-gate finger spacing have improved RF performance and also improved hot carrier and radiation tolerance. The effects of finger width on the hot carrier stress and ionizing radiation degradation of strained silicon-on-insulator RF MOSFETs are also investigated. Enhanced degradation is observed for devices with wide finger widths and is attributed to the greater channel-region mechanical stress induced impact ionization. This result is contrary to the previous studies which showed that narrow channel width devices should exhibit greater damage. Taken together, these results have serious consequences for RF circuits that require large widths for sufficient RF gain. Finally, devices with symmetric halo doping are observed to exhibit greater total-dose degradation than devices with asymmetric halo doping. [ABSTRACT FROM PUBLISHER]

We have examined the reliability risks of complementary SiGe HBTs on thick-film silicon on insulator (SOI). DC stress techniques, such as reverse emitter–base (EB) stress, mixed-mode stress, and flyback measurements, were used to characterize the safe operating area of n-p-n and p-n-p SiGe HBTs fabricated on SOI substrates. The measurements were analyzed based on fundamental damage mechanisms, such as hot carriers generated at the EB and collector–base junctions during large reverse voltage, and thermal runaway as a result of high current phenomena. RF stress (using a large amplitude continuous-wave signal) was also performed to examine the reliability of complementary bipolar complementary metal–oxide–semiconductor devices and circuits in an RF context. In both cases, p-n-p SiGe HBTs were found to be more reliable than n-p-n SiGe HBTs, a fact that may offer opportunities for circuit design optimization. [ABSTRACT FROM PUBLISHER]

Purpose/Objective: On 11 March 2020, the World Health Organization declared COVID-19 a pandemic, and universities transitioned to online learning. The objective of this study was to evaluate the experience of students with the online education program offered during the initial phase of the pandemic. Methods: In April 2020, an anonymous online survey was distributed to 248 undergraduate dental and dental hygiene students in Dalhousie University's faculty of dentistry. The survey contained 10 Likert-type and 3 open-ended questions asking students to evaluate their online learning experience and their preferences regarding in-person and online learning. Results: The response rate was 62.5%. Two-thirds (65.8%) of respondents reported that their educational experience in a virtual setting was very or somewhat positive, while only 14.8% said it was negative or somewhat negative. However, 60.6% agreed or strongly agreed that they preferred face-to-face learning over virtual classroom learning. Students were evenly split on whether online teaching should replace classroom teaching where possible (38.1% agreed/strongly agreed, 39.3% disagreed/strongly disagreed). Analysis of the responses to open-ended questions gave rise to 6 themes: online teaching and assessment methods; helpful online instructor behaviours/traits; advantages of online learning; disadvantages of online learning; combining online and in-person learning; online learning during the pandemic. Conclusions: Although the sudden transition to online learning was generally well received by students, there still appears to be support for maintaining some form of traditional, face-to-face learning methods in dental education. Students felt that ensuring faculty were creative, understanding and flexible was paramount in the transition to teaching in an online format. [ABSTRACT FROM AUTHOR]

So, the fateful day is here. Your inbox is crammed with e-mails reminding you that you must absolutely not miss the engineering career fair in the student center. Mailing lists you are signed up for are reminding you to check out "Innovation Days" and "Hackathons" sponsored by companies visiting campus for recruiting. Doing all this in the middle of an already overscheduled day when you'd rather be going to class to learn, finishing lab reports, or just being out throwing a ball around, is a rather unappealing option. Do not despair! Having toiled on both sides-from selling myself to employers, to selling my employers on prospective candidates-I proffer a few suggestions that will make this season's career fair, as well as any on-the-spot or next-day interviews, much less stressful and allow you to get the most out of them! [ABSTRACT FROM PUBLISHER]

We investigate, for the first time, the feasibility of operating silicon–germanium (SiGe) heterojunction bipolar transistors (HBTs) in a weakly saturated bias regime to enable ultralow-voltage RF front-end design. Measured dc, ac, and RF characteristics of third-generation high-performance SiGe HBTs operating in weak saturation are presented. Robust RF operation of \0.12 \times \6.0\ \mu\m^2 SiGe HBTs are demonstrated in a common–emitter configuration at collector-to-emitter voltages above 0.15 V. A noise figure of 1.33 dB and an input third-order intercept point above -8 dBm for a 3-GHz input tone are achieved at 0.30 V. These results have potential implications for RF circuits used in severely power-constrained systems. [ABSTRACT FROM AUTHOR]

In this article, the author discusses a systematic review that revealed the equal effectiveness of resin-based and glass ionomer cement (GIC) fissure sealants in preventing dental carries. The author says that the review has two weaknesses, such as the assumption of tooth pairs' independence and the application of a fixed effects model in heterogeneity determination. The author also mentions that based on the limited evidence, neither resin-based nor GIC fissure sealants are of high quality.

This issue marks the 30th anniversary of IEEE Potentials. As I read the first-ever issue, which came out in the winter of 1982, I am struck by the relevance of some electrical engineering (EE)-related issues that were being discussed back then (e.g., the “work versus grad school” debate). Other issues pertinent to EE today didn't even exist in 1982; the first-ever personal computer shipped a few months after the first issue was published. We know how good the past 30 years have been to EE. How about the next 30? On the eve of IEEE Potentials' 30th anniversary, I talked to mavens in industry and academia to gather their insights about what EE would look like 30 years from today. I arrived at a sobering conclusion—the future of EE is not at all controlled by electrical engineers. Let that sink in before you proceed. [ABSTRACT FROM PUBLISHER]

Summer is upon us; senior-year students have graduated. Prized belongings were passed on to those still trying to claw their way out of school. Seizing this opportunity, I think it would be apt to peddle some of my own nuggets of “wisdom” to the readers of IEEE Potentials to make their academic and professional lives a little more rewarding. Why should you listen to me? Well, because I'm the guy who learned the hard way that getting something to “work” is only 20% of the battle won in launching a new product or that the surly guy you refuse to acknowledge at the gym is an executive at a firm that you've been trying to get into. It sure helps to know these kinds of things, right? [ABSTRACT FROM PUBLISHER]

Purpose/objective: On 11 March 2020, the World Health Organization declared COVID-19 a pandemic, and universities transitioned to online learning. The objective of this study was to evaluate the experience of students with the online education program offered during the initial phase of the pandemic., Methods: In April 2020, an anonymous online survey was distributed to 248 undergraduate dental and dental hygiene students in Dalhousie University's faculty of dentistry. The survey contained 10 Likert-type and 3 open-ended questions asking students to evaluate their online learning experience and their preferences regarding in-person and online learning., Results: The response rate was 62.5%. Two-thirds (65.8%) of respondents reported that their educational experience in a virtual setting was very or somewhat positive, while only 14.8% said it was negative or somewhat negative. However, 60.6% agreed or strongly agreed that they preferred face-to-face learning over virtual classroom learning. Students were evenly split on whether online teaching should replace classroom teaching where possible (38.1% agreed/strongly agreed, 39.3% disagreed/strongly disagreed). Analysis of the responses to open-ended questions gave rise to 6 themes: online teaching and assessment methods; helpful online instructor behaviours/traits; advantages of online learning; disadvantages of online learning; combining online and in-person learning; online learning during the pandemic., Conclusions: Although the sudden transition to online learning was generally well received by students, there still appears to be support for maintaining some form of traditional, face-to-face learning methods in dental education. Students felt that ensuring faculty were creative, understanding and flexible was paramount in the transition to teaching in an online format.

Objective: To measure the light energy that dental students delivered to a simulated Class I restoration before training, immediately after training and 4 months after training., Methods: Thirty-eight (38) dental students used a single light-emitting diode curing light (SmartLite iQ2, Dentsply) to cure, for 10 seconds, a simulated Class I restoration positioned in the Managing Accurate Resin Curing - Patient Simulator (BlueLight analytics inc.). The students then attended an instructional lecture and received individualized instruction on optimizing their light-curing technique. The students were retested immediately after instruction and again 4 months later (without further instruction). The irradiance and energy delivered during light-curing were calculated for each student at all 3 time points. Mean values were calculated and compared., Results: Before instruction, the students delivered between 0.1 and 7.2 J/cm2 of energy (mean ± standard deviation [SD] 4.1 ± 1.7 J/cm2). After instruction, the same students delivered between 5.8 and 7.5 J/cm2 of energy (mean ± SD 6.7 ± 0.4 J/cm2). Analysis of variance and Fisher's Protected Least Significant Difference tests showed that instruction with the patient simulator led to a significant improvement in the amount of energy delivered and that the students retained this information. When retested 4 months later, the students delivered between 4.2 and 7.9 J/cm2 of energy (mean ± SD 6.1 ±1.1 J/cm2). Although this was less energy than immediately after instruction, the decline was not significant (p = 0.44)., Conclusions: Provision of immediate feedback on light-curing technique and instruction on how to avoid mistakes led to a significant and lasting improvement in the amount of energy delivered by the students.