We propose a 50-MS/s two-step flash-ΔΣ time-todigital converter (TDC) using stable time amplifiers (TAs).The TDC demonstrates low-levels of shaped quantization noise. The system is simulated in 40-nm CMOS and consumes 1.3 mA from a 1.1 V supply. The bandwidth is broadened to Nyquist rate. At frequencies below 25 MHz, the integrated TDC error is as low as 143 fsrms, which is equal to an equivalent TDC resolution of 0.5 ps.

This paper proposes a new RF oscillator topology that is suitable for ultra-low voltage and power applications. By employing alternating current source transistors, the structure combines the benefits of low supply voltage operation of conventional NMOS cross-coupled oscillators together with high current efficiency of the complementary push-pull oscillators. In addition, the 1/f noise upconversion is also reduced. The 40nm CMOS prototype exhibits an average FoM of 189.5 dBc/Hz over 4–5 GHz tuning range, dissipating 0.5mW from 0.5V power supply, while abiding by the technology manufacturing rules.

In this paper, the design and measurement results of a 1.8 GHz to 2.3 GHz broadband Doherty power amplifier (DPA) are reported. A modified load modulation network is designed to minimize impedance transformation ratio over the entire dynamic range for the purpose of extending the operating bandwidth. Experimental results show that the drain efficiency of the proposed DPA maintains above 50% and 63% with continuous wave input signal powers of 26 dBm and 34 dBm, respectively, from 1.8 GHz to 2.3 GHz. When stimulated by a 60-MHz, 12- carrier UMTS signal at 2.14 GHz, the proposed DPA achieved an average efficiency of 53% at 7.6 dB back-off, while the corresponding adjacent channel leakage ratio is linearized to -48.4 dBc with digital predistortion.

The 1/f (flicker) noise upconversion degrades the close-in spectrum of CMOS RF oscillators. The resulting 1/f3 phase noise (PN) can be an issue in PLLs with a loop bandwidth of <;1MHz, which practically implies all cellular phones. A previously published noise-filtering technique [1] and adding resistors in series with gm-device drains [2] have shown significant reduction of the 1/f3 oscillator PN corner. However, the former needs an additional tunable inductor and the latter degrades PN in the 20dB/dec region.

CHAGS13 took place from 27th June to 2nd July in University College Dublin, Ireland, and is convened by Prof. Graeme Warren. With 250+ papers across 30 sessions, an exciting academic programme explored the Conference theme: “Living Well Together”, combined with a host of unique activities and experiences and Irish craíc for an unforgettable week!

This paper proposes a power-efficient capacitor-array-based digital-to-time converter (DTC) using a constant-slope approach. Fringe-capacitor-based digital-to-analog converter (C-DAC) array is used to regulate starting supply voltage of the constant slope fed to a fixed threshold comparator. The proposed DTC consumes only 15 μW from a 1V supply, while achieving fine resolution of 103 fs when running at 40 MHz. The measured INL and DNL are 0.73/0.35 LSB within a 5-bit range. The DTC achieves the best figure-of-merit of 8.5 fJ among state-of-the-art when normalizing the product of power and INL to the product of input frequency and range.

This paper presents the design of a frequency selectable oscillator used as part of a new data acquisition architecture for digital predistortion (DPD) of RF power amplifiers (PAs). The proposed architecture aims to alleviate the requirement of high sampling rate analog-to-digital-converters (ADCs) in the data acquisition loop. The oscillator utilizes switchable capacitors with a digital control scheme and is capable of operating between 2.0 GHz and 2.5 GHz with an approximate frequency step size of 512 kHz.

Economic volcanic - hosted massive sulfide (VHMS) deposits of the Archean Yilgarn Craton, Western Australia, are restricted to zones of juvenile crust as revealed through regional Nd, Pb and Hf isotopic variations and the geochemistry of felsic volcanic rocks. Interpreted as Archean paleo - rift zones, one of these runs N - S through the Eastern Goldfields Superterrane (broadly coincident with the Kurnalpi Terrane) and is associated with the high grade ca. 2690 Ma Teutonic Bore, Jaguar and Bentley deposits, plus sub - economic VHMS mineralization further south. To date, only small, historic Cu deposits (e.g. Anaconda) and barren pyritic lenses have been recognised in the older 2.7 Ga plume - dominated lower stratigraphy of the Eastern Goldfields.

The 2010 Annual Meeting of the European Federation of Food Science and Technology (EFFoST) took place in Dublin, Ireland on 10-12 November. Twenty four papers and 275 posters were presented, and there were 290 attendees. The theme of the Conference was 'Food and Health'. There were five oral sessions: (i) Nutrition and Health; (ii) Functional Foods [a]; (iii) Functional Foods [b]; (iv) Processing for Healthy Foods, and (v) Food Safety and Health. The poster sessions corresponded to these themes.

The 2011 European Federation of Food Science and Technology (EFFoST) conference took place in Berlin, Germany on 9-11 November. The conference programme centred on food process-structure-function relationships and the content was closely allied to the research agenda of the European Technology Platform: Food for Life. There were 16 keynote/review lectures, 38 other oral presentations, 260 posters, and close to 300 attendees. The oral sessions corresponded to the process-structure-function themes as did the poster sessions.

This paper introduces a phase shifter based on switched filters for mm-wave 5G MIMO transmitters. It is realized in 22 nm FD-SOI CMOS and exploits the use of back-gate biasing. The new approach features strong tolerance to process, voltage and temperature (PVT) variations and thus can maintain low phase error with fine phase tuning capability supporting a large bandwidth. Measurement results show that the 4-bit phase shifter achieves 3.5° rms phase error at 28 GHz. The proposed phase shifter can maintain <5° of the worst-case rms phase error when operating across 24 to 29.5 GHz resulting in 20.56% fractional bandwidth which is the largest among the published switched-filter phase shifters to date.

This paper proposed a new dual-band dual-polarized array antenna operating at 28 GHz and 38 GHz for 5G communication applications. Three stacked patches are adopted to achieve the dual-band operation. The lower band from 27.48 to 28.50 GHz is achieved by using the lower large patch, which is couple-fed by the middle patch. While the upper band from 36.94 to 40.43 GHz is achieved by using the middle and upper patches. The two patches resonant at 38 and 40 GHz respectively and the two resonant modes coupled together, which greatly enhances the upper band. To increase the polarization isolation in the lower band, a shorting pin connecting the lower patch and ground is utilized. Taking advantages of the multi-layer technology, the position of the vertical feeding probe between the middle patch and lower patch is slightly shifted to ensure the good impedance matching in both lower band and upper band. For the antenna element, the simulated -12 dB bandwidths are 27.48-28.50 GHz and 36.94-40.43 GHz for the two bands, respectively. The in-band gains are over 6 dBi in the lower band, and over 4 dBi in the upper band. For the 2×2 antenna array, the isolations are better than 20 dB in both bands.

The 2D non-separable linear canonical transform (2D-NS-LCT) can describe a variety of paraxial optical systems. Digital algorithms to numerically evaluate the 2D-NS-LCTs are not only important in modeling the light field propagations but also of interest in various signal processing based applications, for instance optical encryption. Therefore, in this paper, for the first time, a 2D-NS-LCT based optical Double-random-Phase-Encryption (DRPE) system is proposed which offers encrypting information in multiple degrees of freedom. Compared with the traditional systems, i.e. (i) Fourier transform (FT); (ii) Fresnel transform (FST); (iii) Fractional Fourier transform (FRT); and (iv) Linear Canonical transform (LCT), based DRPE systems, the proposed system is more secure and robust as it encrypts the data with more degrees of freedom with an augmented key-space.

This paper presents a mmW frequency generation stage aimed at minimizing phase noise via waveform shaping and harmonic extraction while suppressing flicker noise upconversion via proper harmonic terminations. A second-harmonic tank resonance is assisted by a proposed embedded decoupling capacitor inside a transformer for shortest and well controlled common-mode current return path. Class-F operation with third-harmonic boosting and extraction techniques allow maintaining high quality factor of a 10 GHz tank at the 30 GHz frequency generation while providing implicit divide-by-3 functionality. The proposed 27.3-31.2 GHz oscillator is implemented in 28-nm CMOS. It achieves phase noise of-106 dBc/Hz at 1-MHz offset and figure-of-merit (FoM) of -184 dB at 27.3GHz. Its flicker phase-noise (1/f3) corner of 120 kHz is an order-of-magnitude better than currently achievable at mmW.

In this paper, 3D CFD models of a bridge section of the Queensferry Crossing Bridge including a bus and other secondary structures on the deck are developed in OpenFOAM using the k-ω-SST turbulence model to determine the aerodynamic coefficients. The aerodynamic performance of the bridge deck accounting for several angles of attack with the bus located in various traffic lanes is investigated. The models are then validated with wind tunnel test results and good agreement is found between the 3D CFD models and the wind tunnel tests. The importance of the validated models is that they can be used in the future to study what wind speed should be set as a limit to prevent high-sided vehicles from overturning on the Queensferry Crossing Bridge.

This paper discusses the problem of joint location and orientation estimation of a receiver using only angle of arrival (AOA) information. Conventional formulations of the problem consist of a number of nonlinear equations where the number of unknowns exceeds the number of equations. However, formulations presented in this paper simplifies the problem in a way that leads of efficient solutions. Two solutions are presented and their performance is compared via simulations using an indoor application as an example. Results emphasize the effectiveness of the the proposed methods.

The SIGCSE Technical Symposium is celebrating its 50th year, and a constant theme throughout this history has been to better understand how novices learn to program. In this paper, we present a perspective on the evolution of introductory programming education research at the Symposium over these 50 years. We also situate the Symposium’s impact in the context of the wider literature on introductory programming research. Applying a systematic approach to collecting papers presented at the Symposium that focus on novice programming / CS1, we categorized hundreds of papers according to their main focus, revealing important introductory programming topics and their trends from 1970 to 2018. Some of these topics have faded from prominence and are less relevant today while others, including many topics focused on students—such as making learning programming more appropriate from gender, diversity, accessibility and inclusion standpoints—have garnered significant attention more recently.We present discussions on these trends and in doing so, we provide a checkpoint for introductory programming research. This may provide insights for future research on how we teach novices and how they learn to program.

A 60 GHz frequency generator with implicit ÷3 divider is proposed in this work to improve the system-level efficiency and phase noise. A third-harmonic boosting technique is utilized to simultaneously generate 20GHz and sufficiently strong 60 GHz signals in order to avoid any divider operating at 60 GHz. The prototype is fabricated in 40nm CMOS and exhibits a phase noise of −100 dBc/Hz at 1MHz offset from 60 GHz carrier and 25% tuning range. The phase noise and FoMT (figure-of-merit with tuning range) are improved by 5 dB and 4.6 dB, respectively, compared to state-of-the-art.

Although the fifth generation wireless networks are yet to be fully investigated, the vision and key elements of the 6th generation (6G) ecosystem have already come into discussion. In order to contribute to these efforts and delineate the security and privacy aspects of 6G networks, we survey how security may impact the envisioned 6G wireless systems with the possible challenges and potential solutions. Especially, we discuss the security and privacy challenges that may emerge with the 6G requirements, novel network architecture, applications and enabling technologies including distributed ledger technologies, physical layer security, distributed artificial intelligence (AI)/ machine learning (ML), Visible Light Communication (VLC), THz bands, and quantum communication

Outbreaks of congenital chondrodystrophy and joint laxity have been described globally in cattle herds for over 20 years. Previous outbreaks have been characterised by calves that are born with a variety of clinical signs which include; disproportionate dwarfism, shortening of the long bones, distal joint laxity, domed crania, brachygnathia, spinal deformities and stillbirth (1). Although the exact aetiology of this condition is incompletely understood, it is taught to be the result of a maternal deficiency in key nutrients during the mid-gestation and is seen most often in beef herds. Epidemiological patterns highlight a number of precipitating risk factors during mid-gestation including; drought periods, feeding only grass silage and feeding silage low in manganese and/or zinc (1). The objective of this case description is to describe the epidemiological patterns observed in a herd outbreak that occurred in a seasonal calving dairy herd in Ireland. In this outbreak, 5 calves out of a total of 123 dairy cows (3.7%) were born affected by congenital chondrodystrophy and joint laxity between January and March 2024. Two affected calves were dwarfs with joint laxity ofn all four limbs, while the remaining 3 were normal in size but had joint laxity affecting all four limbs. All affected calves were born exclusively to heifers (i.e. primipara) and the total proportion of affected calves born to heifers was 17.2% (5/29). All affected calves were Holstein Friesian (HF) females due to the exclusive use of sexed semen in these heifers on the farm. Of the 5 affected calves, 3 calves were sired by one bull while 2 were sired by another bull indicating that a genetic aetiology related to the sire was less likely. Average birthweight of affected calves was 28.9 kg (SD = 2.8 kg) while average birthweight of unaffected HF females on this farm was 33.8 kg (SD = 3.1 kg). As all the dams were heifers, they were managed separately to the cows on the farm in terms of grazing and housing. These heifers were grazing from breeding in May to October at which point they were housed until calving. Commencement of housing corresponded to approximately 125-160 days of gestation for affected dams and during housing, they were fed a diet of grass silage exclusively. Trace element analysis of the grass silage fed showed high levels of iron, cobalt, selenium, aluminium and molybdenum but low levels of manganese (53.5 mg/kg of dry matter) and zinc (23.8 mg/kg of dry matter). Low levels of manganese and/or zinc have been associated with congenital chondrodystrophy and joint laxity in reports from similar grazing systems (2). In conclusion, outbreaks of congenital chondrodystrophy and joint laxity can occur in seasonal calving dairy systems due the nature of animals all being at a similar stage of gestation when a nutritional deficit occurs. Groups of in-calf heifers may be at increased risk especially if they are housed early and are maintained only on grass silage that is lower in either manganese or zinc.