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Certificateless strong designated verifier signature schemes have realized the merit of CL-PKC against the traditional strong designated verifier signatures. However, when the signer and the designated verifier disagree with the signature, existing schemes cannot distinguish the original signature from the signature transcript. In addition, errors or malicious actions introduced by the designated verifier may lead to the failure of signature verification. To solve these issues, we propose a certificateless verifiable strong designated verifier signature scheme. When disputes arise between the signer and the verifier, the scheme can effectively prevent the signer from denying the signature generated by the signer, as well as the designated verifier from denying valid signatures or invalid ones. Our scheme does not rely on bilinear pairings. The proposed scheme satisfies the requirements of verifiability, unforgeability, non-delegability, non-transferability and signer ambiguity. We also provide formal security proof in the random oracle model for the proposed scheme.

With the development of the advanced precision manufacturing field, the curve profile is becoming more and more complex, and the profile curve evaluation is no longer limited to the two-dimensional plane. Aiming at the difficulty and low efficiency of complex contour evaluation of high-precision parts, this paper proposes a global evaluation method of three-dimensional curve contour. After the curve contour is extracted, dimensioned and calibrated, according to the definition of GB/T1182-2008 plane curve contour, an envelope circle equation is established to evaluate the contour of the complex line. The curve contour theoretical points are used to establish the envelope detection area function, and the position relationship of the measuring points relative to the theoretical contour is evaluated according to the circle function of the envelope group, and the line contour error is determined. Experiments show that the evaluation result is intuitive and can be traced back to the specific area of the curve contour. This method realizes the evaluation of the whole area of the spatially complex curve contour. The method is accurate and efficient, and has overall and unitary characteristics.

To keep up with the dominance in the field of leading semiconductor technology innovation, TSMC has announced the risk production of its most advanced 5nm CMOS logic node [1] using the full-fledged EUV and high mobility channel (HMC) FinFETs. Supporting the state of the art mobile SOC chips and HPC application needs, this 5nm technology node provides ~1.8x improvement in logic density, 15% speed gain and 30% power reduction as compared to its previous 7nm generation [1] - [2] . This paper, for the first time, brings out the detailed reliability attributes for the TSMC 5nm technology node from the device to various chip/package level reliability testing. While delivering an enhanced performance for N5, here we demonstrate the reliability benefit in terms of Bias Temperature Instability (BTI), Hot Carrier Degradation (HCD), Time dependent dielectric breakdown (TDDB) degradation modes in device level. Not only that, N5 node also delivers excellent reliability margins in chip level evaluations for SRAM and logic CPU/GPU applications. Moreover, to compete with the strictest industry reliability requirements even to the DPPM or low DPPB levels, N5 logic confirms its benefit for the automotive applications.

Accelerated lifetime tests are necessary for reliability evaluation of circuits and systems, but the parameters for choosing the test conditions are often unknown. Furthermore, reliability testing is generally performed on test structures that have different properties than actual circuits and systems, which may create inconsistencies in how circuits and systems work in reality. To combat this problem, we use ring oscillators, which are similar to circuits, based on the 14nm FinFET node as the circuit vehicle to extract wearout data. We explore the effects of testing time, sample size, and number of stages on the ability to detect failures for various test conditions, focusing on front-end time dependent dielectric breakdown, which is one of the most dominant wearout mechanisms.

In the last two decades, the concept of student-centered learning and problem-based learning (PBL) have swept through the educational community in most of the advanced countries. In medical PBL education, traditionally in order to train the students to be able to diagnose a patient with certain symptoms, the training procedure is always very time-consuming and labor-intensive. In particular there are usually only very limited number of specialists in practice. In order to solve this problem, we have developed a web-based PBL training system for medical education. The system can emulate a real clinical case that enables students to go through each step of a diagnosis procedure in an attempt to diagnose and cure a patient's disease. We believe that the system can significantly improve the learning efficiency and effectiveness for medical education.

Because data from a variety of wearout mechanisms is confounded in circuits, we apply machine learning techniques to detect the parameters of competing failure mechanisms in ring oscillators, which more closely mimic circuit behavior than test structures. This is the first known application using data analysis to distinguish competing wearout mechanisms in circuit-level data. To quickly and efficiently analyze failure data, we propose to use maximum likelihood estimation to separately determine the parameters of each underlying distribution by only observing the time-to-failure of samples. The quasi-Newton method is used to update and optimize the parameter extraction.

Lifetime testing of circuits is challenging because of the need to design circuit-specific test structures and test patterns. The goal of this work is to find a ring oscillator that matches a circuit’s wearout behavior limited by time-dependent dielectric breakdown (TDDB), electromigration (EM), and stress-induced voiding (SIV) lifetime distributions, which can be used to foreworn circuit breakdown. The equivalent ring oscillator is easier to test, enabling the collection of more experimental lifetime data. Therefore, this paper aims to find the appropriate ring oscillator for a target circuit by mapping the lifetime of a circuit to a ring oscillator using analytical equations that involve layout parameters (area, length, width of device and interconnect) and operating conditions (supply voltage, temperature, probability of stress, current). Practical ring oscillator equations for lifetime estimation were derived, which describe relationships between stage number, oscillation frequency, characteristic lifetime, and Weibull parameters. The methodology is illustrated with example circuits that were implemented with 14nm FinFET technology.

This article tailored the dispersion and increased the birefringence in a photonic crystal fiber (PCF), and then designed a dual function of dispersion flattened / polarization maintaining PCF (DF-PM-PCF). The numeric results indicate that the DF-PM-PCF achieves the dispersions within a window of 0±1.0 ps/nm/km over a bandwidth range of 679 nm(1235 nm∼ 1914 nm). In the meanwhile, the birefringence values of the DF-PM-PCF were estimated and shown that they are larger than 0.30 × 10−3 in the operating band. Furthermore, the confinement losses of the device are calculated and confirmed that they are reasonable. The numeric results indicate that the DF-PM-PCF has confinement losses of 5.5×10−4 dB/km to 1.4×10−2 dB/km in the operating band.

In this paper, we present a real-time method for obstructive sleep apnea (OSA) detection of frequency analysis of ECG-derived respiratory (EDR) and heart rate variability (HRV). The method is computationally simple with ECG signals to determine the time interval of OSA. We compare it to a traditional complexly Polysomnography (PSG) which needs several physiological signals measured from patients. For the wearable real-time application, the simplified Lomb Periodogram is proposed to perform the frequency analysis of EDR and HRV. The data from 900 ECG recordings from MIT PhysioNet Sleep Apnea database was utilized in the paper. The approximated method of OSA method obtained the highest Specificity (Sp) 90.1%, Sensitivity (Se) 94.3%, and Accuracy 92.1%.

In this paper, we describe an e-Learning system that can help novices to learn how to develop some workable programs in a short period of time, assess their performance, and automatically grade the students' programs. The system takes advantage of computer and network technologies and combines the concept of flipped classroom to help the instructor and students in their teaching and learning activities. The system can do semi-automatic grading for the students' program and produce some preliminary results. The preliminary study shows that the platform can indeed assess the students' performance and consequently help the students to learn programming languages more effectively and efficiently.

Replacing Si channel with selective epi-Ge in mainstream bulk FinFETs can be a cost-effective solution for sub-7 nm node, but is facing severe challenges because of poor isolation to Si substrates. We demonstrate a suspended Ge gate-all-around (GAA) nanowire nFET (nNWFET) technology with junction isolation on bulk Si. Because of the low junction leakage provided by an embedded Si junction, improved electrostatics of GAA structure utilizing surrounding high-mobility {111} surfaces, and a dislocation-free channel by selectively removing the defective Ge/Si interface, a high current on/off ratio (I ON /I OFF ) of 5×105, which is comparable to the state-of-the-art Ge nFETs on Ge-on-insulator (GeOI), is first demonstrated using a bulk FinFET-compatible process.

This paper has presented a photoplethysmography (PPG) signal processing system based on ensemble empirical mode decomposition (EEMD) method. Traditionally, empirical mode decomposition (EMD) suffers from mode mixing problem during the decomposition process. This paper adopts EEMD to solve the mode mixing problem by adding different sets of white noise and decompose signal into meaningful intrinsic mode functions. The system is implemented on self-designed platform combined with front-end circuit, EEMD chip by TSMC 90nm CMOS technology, and commercial display devices. The results showed that the proposed EEMD processor can effectively solve the mode mixing problem of EMD. It was helpful for non-stationary biomedical signal processing and cardiovascular diseases research.

Three types of antenna arrays such as uniform linear, uniform rectangular arrays and uniform cube arrays are used in the transmitter and their corresponding channel capacity on several paths in the indoor environment are calculated. Numerical results show that uniform linear arrays is better than that for uniform rectangular arrays and uniform cube arrays system with and without interference.

A junctionless (JL) fin thin film transistor (FinTFT) with a novel shell doping profile (SDP) formed by a damage-free conformal molecular monolayer doping (MLD) method and a combination of microwave annealing (MWA) and CO2 laser spike annealing (COLSA) is demonstrated and studied. MWA drives in and partially activates the MLD dopants; the resultant SDP features an ultra-shallow depth ( 107) for 3D stacked ICs applications. Our results reveal the potential of the proposed SDP formed by MLD, MWA and COLSA enabling a JLFinTFT showing excellent performance.

In this study, an effective real-time obstructive sleep apnea (OSA) detection method from frequency analysis of ECG-derived respiratory (EDR) and heart rate variability (HRV) is proposed. Compared to traditional Polysomnography (PSG) which needs several physiological signals measured from patients, the proposed OSA detection method just only use ECG signals to determine the time interval of OSA. In order to be feasible to be implemented in hardware to achieve the real-time detection and portable application, the simplified Lomb Periodogram is utilized to perform the frequency analysis of EDR and HRV in this study. The experimental results of this work indicate that the overall accuracy can be effectively increased with values of Specificity (Sp) of 91%, Sensitivity (Se) of 95.7%, and Accuracy of 93.2% by integrating the EDR and HRV indexes.

Traditional microscopes are used as basic tools for histology education and have caused many problems in schools. Due to the advances of information technology, some virtual microscopy systems (VM systems) have been developed over years for educational purposes. The VM systems have been proven in the literature to be useful and helpful for students' learning. However, currently, most VM systems just try to mimic the physical microscopes and there is still a lot of room to improve their usefulness for educational purposes. In this paper, we discuss what kinds of features and technologies a VM system should have in order to support various pedagogical strategies. We discuss the features of an ideal virtual microscope system that are needed to make the histology learning more effective and efficient. We have developed a prototype system based on this ideal VM system and some results are demonstrated in this paper. We believe that a VM system with these features will significantly improve the histology learning in education.

Path planning and trajectory generation are the primary tasks for spray painting applications. However, for the most efficient spraying application, the detailed dimensional information of the workpiece along the generated path is essential. This paper introduces the shape signature approach for automatic identification and measurement of cross-sectional information of a bicycle frame model for advanced spraying task of 6-DOF robot. The path planning is generated from skeletal line of the point cloud model of the bicycle frame which is reconstructed by Kinect Fusion based algorithm. Cross-sectional shape and dimensions are autonomously identified along the generated spray-gun path and subsequently the corresponding spray task is applied in each segment. The spray-gun orientation and painting condition such as the spray speed, volume rate and internal and external pressures are automatically adjusted according to the cross-sectional information and nature of the path at the current pose of the end effector.

For the first time, a novel junctionless (JL) FinFET structure with a shell doping profile (SDP) formed by molecular monolayer doping (MLD) method and microwave annealing (MWA) at low temperature is proposed and studied. Thanks to the ultra thin SDP leading to an easily-depleted channel, the proposed JLFinFET can retain the ideal subthreshold swing (∼ 60 mV/dec) at a high doping level according to simulations. Poly Si based JLFinFETs processed with MLD and MWA exhibit superior subthreshold swing (S.S. ∼ 67mV/dec) and excellent on-off ratio (>106) for both n and p channel devices. Threshold voltage (V TH ) variation due to random dopant fluctuation (RDF) is reduced in MLD-JLFinFETs, which can be attributed to the molecule self-limiting property of MLD on the Si surface and quasi-diffusionless MWA at low temperature. Our results reveal the potential of the proposed SDP enabling a JLFET showing reduced variation and outstanding performance for low power applications.

In this paper, the problem of adaptive output feedback stabilization of uncertain systems is investigated. A systematic algorithm for obtaining the adaptive output feedback control gain which guarantees the boundedness of all state variables is proposed. And then when both the considered system and its corresponding adaptive law are with state-dependent impulse disturbances, sufficient conditions will be derived such that the uncertain system will be robustly practically stable. Furthermore, requiring only the motor position for feedback, the adaptive scheme will be applied to construct the controllers for permanent magnet (PM) and variable reluctance (VR) stepper motors. Finally, simulation studies are presented to validate the controller performance.

In this study, we use the Cu/SnAg/Ni/Cu joint with a thickness of 7μm/8μm/2μm /5μm and 7μm/16μm/2μm /5μm. The diameter of the solder joint is about 30 μm and the UBM opening is 18 μm in diameter with 60 μm pitches. In order to measure the resistance changes, it was fabricated which constitute four probes. By using this method we can measure the resistance changes in microbump excluding the resistance changes in the wiring trace to make it more sensitive to subtle microstructure changes. We investigated the mechanisms of electromigration in microbumps with different stages when resistance increased 20%, 50% and 100% of the initial resistance. Solder joints were stressed with 0.56 A on 150°C hot plate. The average current density is 8 × 104 A/cm2, calculated based on the UBM opening. We ground the samples with 1000, 2000, and 4000 sand paper and then polished them with 1 μm, 0.3 μm, and 0.05 μm Al 2 O 3 We observed their morphologies with SEM and measured their component with EDX. In the bump with electron flow upward, we observed that microbumps were transformed into Cu 6 Sn 5 IMCs and Cu 3 Sn IMCs joints. In addition, voids were formed at the interface between nickel and solder. We found that both void formation and UBM dissolution were occurred. In the bump with electron flow downward, microbumps were transformed into IMC joints without void formation. To sum up, this study provides a better understanding on the relationship between the behavior of resistance curve and the morphology changes in microbumps.

High performance Ge inversion (INV) and junctionless (JL) gate-all-around (GAA) FETs are demonstrated on epi-Ge layer on SOI. The anisotropic etching is used to remove the defect near the Ge/Si interface and to form gate-all-around structure. The INV and JL pGAAFETs have I on of 235 µA/µm and 270 µA/µm at V GS − V T = −2 V and V DS = −1 V, respectively, and show good subthreshold characteristics. The (111) sidewall INV nFETs show 2X enhanced I on of 110 µA/µm with respect to the devices with near (110) sidewalls.

The channel capacity of multiple-input multiple-output (MIMO) wireless local area network (MIMO-WLAN) systems with co-channel interference (CCI) is calculated in this paper. The ability to combat CCI for the MIMO-WLAN simple uniform linear array (ULA) and polarization diversity array (PDA) are investigated. The channel frequency response, which is further used to calculate the corresponding channel capacity is calculated by ray-tracing approach. Numerical results show that MIMO-PDA is better than those of MIMO-ULA when interference is present.