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All DC offshore wind farms are gaining popularity for long-distance and high-power offshore wind energy conversion. It calls for high-power DC/DC converter with high step-up ratio for interconnecting the medium-voltage DC collection and the high-voltage DC transmission systems. This paper proposes a monopolar symmetrical DC/DC converter, which is featured with partial-power processing and presents less installed capacity of components, low cost, low power loss, lightweight, and small footprint. Moreover, a modified phase-shifted carrier pulse-width modulation with variable carrier frequency is developed to further reduce the switching loss and keep the dynamic current tracking performance. Effectiveness of the proposed converter has been verified by simulation study of a 400MW, 25kV/250kV model and experimental results of a 5.4kW, 60V/320V scaled-down prototype.

Background Population growth, climate change, and food shortage have led to increased demand for alternate sources of lipids to meet our food and energy needs. Oleaginous microorganisms such as yeasts, bacteria, microalgae, fungi, and thraustochytrids are good resources for producing lipids. Scope and approach Many factors affect the amount and composition of lipid accumulation in microorganisms, such as genetic makeup and environmental conditions during growth, such as carbon and nitrogen sources, pH, temperature, and exposure to natural light in growing media. Food biotechnology advances such as improvements in fermentation technology, genetic and metabolic engineering of oleaginous microorganisms, and the use of low-cost carbon sources, such as food and agricultural waste materials, make lipid production using microbial sources more feasible. Key findings and conclusions Microbial lipid production has some unique benefits for the production of specialty fats and oils, including cocoa butter equivalents, polyunsaturated fatty acid oils and biosurfactants. Moreover, microbial oil production has advantages over plant and marine oils, including lower cultivation costs and the ability to engineer oil structure and thus functionality using genetic modification. Microbial oils production allows for the production of more sustainable and safer oils, without pesticides, herbicides or heavy metals, year-round with a small footprint and without the need for land.

A temperature sensor named a thermillator (thermo-oscillator) is demonstrated, consisting of a single device with an n+-emitter, p-base and n+-collector. The thermillator with a p-base floating body shows inherent oscillation behavior. The underlying mechanism of the thermillator is based on the single transistor latch (STL). Oscillation originates with the iterative charging and discharging process in the floating p-base, and the oscillation frequency ( $\boldsymbol {f}$ ) is sensitively changed by applied temperature. Compared to a temperature sensor with a circuit-based ring oscillator, the single device-based thermillator has the advantages of small footprint area, low hardware cost, and low power consumption.

Membranes are widely used in separation processes due to their low energy requirement, small footprint and simplicity. New membranes have been developed based on novel materials and fabrication techniques to address separation challenges in the field of membrane science. In the case of liquid phase separations, ion-ion separation and chiral resolution using membranes have attracted growing interest for their applications such as in high-value mineral extraction and pharmaceutical manufacturing. Furthermore, reverse osmosis operation favors ultra-high-pressure range for treating feed with higher salinity with higher water recovery. Herein we highlight the latest development and design approaches of single species-selective membranes and pressure-resistant membranes and discuss the current limitations of membrane separation in the liquid phase. We subsequently review recent advancement in the fabrication techniques that enable the making of these membranes from emerging materials.

Optomechanical sensing based on the coupling between mechanical motions and optical resonances has attracted huge interest in sensor applications due to its small footprint, high sensitivity, low detection limit, and electromagnetic immunity. Optomechanical sensors that detect from mechanical motion at µm scale to molecular vibration at nm scale have found various applications such as force, inertia, acoustic, chemical, and thermal sensing, etc. In this review, we provide an overview of the recent progress of optomechanical sensors. Three development fields of optomechanical sensors are reviewed, which are passive optomechanical sensors, electro-optomechanical sensing platforms, and molecular vibration sensing schemes. The sensor configurations, applications, and integrations are described. In the end, we also provide our perspectives on the future development directions of optomechanical sensors.

The timely diagnosis of active tuberculosis disease (TB) is crucial to interrupt the transmission and combat the spread of Mycobacterium tuberculosis (Mtb), the causative agent for TB. Here, we demonstrate the development of a specimen-direct rapid diagnostic method for TB which consists of an isothermal amplification device, Tiny Isothermal Nucleic acid quantification sYstem (TINY), coupled with helicase-dependent amplification (HDA). HDA, an isothermal amplification technique is established over TINY using pUCIDT-AMP vector carrying IS6110, the target DNA sequence for Mtb. The limit of detection of this technique for detecting the IS6110 within a threshold time of 50 min is 2.5 × 105 copies of IS6110. HDA in TINY for TB detection was evaluated using three IS6110-positive Mtb strains - H37Rv, CDC 1551, and Erdman wild-type and one IS6110-negative Mycobacterium avium. For spiked oral swabs, HDA in TINY detects IS6110 without any non-specificity in relatively short turnaround time (

Dye-sensitized solar cells (DSCs) have proven to be one of the best photovoltaic approaches for harnessing indoor/artificial light. Herein, we report two new molecularly engineered, cost-effective, metal-free, carbazole-based D–π–A sensitizers (YK 8 and YK 9) by judiciously varying their π-spacers, which are suitable for indoor photovoltaic applications. Using YK 8, we achieved an efficiency of 28.7% under standard 1000 lux Osram 14 W T2 cool day light fluorescent tube illumination with a power output of 68.88 μW cm−2 and 30.24% with a power output of 108.85 μW cm−2 under a higher illumination intensity of 1500 lux without co-sensitizers using iodide/triiodide electrolyte. With a small footprint/active area of 1.24 cm2, we could power a temperature sensor completely autonomously at a low light intensity of 500 lux, displaying the potential of these indoor photovoltaic devices to serve as energy sources for low-power sensors and actuators on the Internet of Things (IoT) network, reducing the dependence on batteries and leading to a smaller carbon footprint. The role of the π-spacer and its influence on recombination and device performance were explored via extensive interfacial studies.

The explosive rise of silicon photonics has led to renewed interest in the electro-optic (EO) or Pockels effect due to its potential uses in many next generation device applications. To find materials with a strong EO response in thin film form, which are essential for low power and small footprint devices, one needs to find a general design rule for strong Pockels materials. To elucidate what makes the Pockels effect strong, we study the effect in LiB3O5 (LBO) and CsB3O5 (CBO) and use these materials as prototypical examples of where conventional wisdom breaks down. We find the Pockels tensor components to be extremely small in both materials, despite the large degree of anharmonicity in the crystals, which has been used as a proxy for the presence of nonlinear electronic effects. We relate the lack of EO response to the large optical phonon frequencies (despite the relatively large Raman susceptibility) in LBO and to the small Raman susceptibility (despite the low phonon frequencies) in CBO, respectively. We shed light on the underlying physical phenomena behind the Raman susceptibility, which we find to be intimately linked to the electron–phonon coupling strength of the near-edge electronic states, and identify a route to discovering new strong EO materials.

Natural hydrocarbon seeps are ubiquitous along continental margins. Despite their significance, we lack a basic understanding of the long-term temporal variability of seep dynamics, including bubble size, rise velocity, composition, and upwelling and entrainment processes. The shortcoming makes it difficult to constrain the global estimates of oil and gas entering the marine environment. Here we report on a multi-method approach based on optical, acoustic, satellite remote sensing, and simulations, to connect the characteristics of a hydrocarbon seep in the Gulf of Mexico to its footprint on the sea surface. Using an in-situ camera, bubble dynamics at the source were measured every 6 h over 153 days and the integrated total hydrocarbon release volume was estimated as 53 m3. The vertical velocity was acoustically measured at 20 m above bed (mab) and found to be approximately 40% less than the dispersed-phase at the source, indicating that the measured values are reflecting the plume continuous-phase flow. Numerical simulations predict that the oily bubbles with diameters larger than 8 mm reach the surface with a small footprint, i.e. forming an oil slick origin, deflection of which with wind and surface current leads to the formation of an oil slick on the surface. Nineteen SAR images are used to estimate the oil seepage rate from GC600 for 2017 giving an average discharge of 14.4 cm3/s.

PURPOSE To demonstrate the utility of an ultrasonic aspirator (Sonopet, Stryker Corporation; Kalamazoo, MI) for debulking firm, soft tissue masses of the orbit. METHODS Case series. The ultrasonic aspirator was used to debulk firm, soft tissue masses in 3 cases. The initial patient had a large orbitofacial mass extending to the inferior and lateral orbital apex secondary to IgG4 disease. The second patient had a lacrimal sac adenocarcinoma extending to the medial orbital apex. The third patient had a large orbital mass extending to the apex secondary to granulomatosis with polyangiitis. RESULTS The ultrasonic aspirator facilitated debulking of infiltrative firm soft tissue masses of the orbit. The device's ability to emulsify, irrigate, and aspirate, along with its small footprint, facilitated precise sculpting and debulking to an extent which would have been difficult otherwise due to location. CONCLUSIONS The ultrasonic aspirator allows precise sculpting of infiltrative firm soft tissue masses in the orbit and is particularly useful in cases with challenging anatomical access.

Optical micro-ring resonator (MRR) sensors are an emerging technology that attracts attention not only because it’s small footprint but also because of its high-quality features. In this work, a Silicon on Insulator (SOI)-based MRR sensor is studied for a practical label-free sensor. After the analysis of this study, it is found that a smaller (compare to previous studies) label-free optical sensor with a sensitivity of 206nm/RIU and a q-factor of 17900 can be obtained when the optimal designed parameters are used. Thus, it is believed that, this work would shed a light on optical sensor technology for more compact-efficient, low-cost and complementary metal-oxide-semiconductor (CMOS)-compatible sensors for daily life usage.

Plasmonic sensors are ideally suited for the design of small, integrated, and portable devices that can be employed in situ for the detection of analytes relevant to environmental sciences, clinical diagnostics, infectious diseases, food, and industrial applications. To successfully deploy plasmonic sensors, scaled-down analytical devices based on surface plasmon resonance (SPR) and localized surface plasmon resonance (LSPR) must integrate optics, plasmonic materials, surface chemistry, fluidics, detectors and data processing in a functional instrument with a small footprint. The field has significantly progressed from the implementation of the various components in specifically designed prism-based instruments to the use of nanomaterials, optical fibers and smartphones to yield increasingly portable devices, which have been shown for a number of applications in the laboratory and deployed on site for environmental, biomedical/clinical, and food applications. A roadmap to deploy plasmonic sensors is provided by reviewing the current successes and by laying out the directions the field is currently taking to increase the use of field-deployed plasmonic sensors at the point-of-care, in the environment and in industries.

In recent years, the number of permanent residents in Chengdu, Sichuan Province, China has continued to grow, and the number of private cars keeps rising. A series of problems caused by difficult parking and random parking in old communities are common. This paper will take the parking problem of the old community in Yingmenkou community, Chengdu, China as an example to summarize the current situation and parking problems of the private car parking facilities in these old communities. Based on Chengdu’s current old community parking management policy, parking facility renovation and expansion policy, this paper researches and establishes a parking resource sharing model suitable for old communities. The simulation results show that this model has a small footprint and is easy to install and disassemble. It can be freely spliced and combined units according to the size of the old community and the needs of residents. It is suitable for old communities with no centralized parking lot and high parking demand by residents.

Much of the biopharmaceutical industry's success over the past 30 years has relied on products derived from Chinese Hamster Ovary (CHO) cell lines. During this time, improvements in mammalian cell cultures have come from cell line development and process optimization suited for large-scale fed-batch processes. Originally developed for high cell densities and sensitive products, perfusion processes have a long history. Driven by high volumetric titers and a small footprint, perfusion-based bioprocess research has regained an interest from academia and industry. The recent pandemic has further highlighted the need for such intensified biomanufacturing options. In this review, we outline the technical history of research in this field as it applies to biologics production in CHO cells. We demonstrate a number of emerging trends in the literature and corroborate these with underlying drivers in the commercial space. From these trends, we speculate that the future of perfusion bioprocesses is bright and that the fields of media optimization, continuous processing, and cell line engineering hold the greatest potential. Aligning in its continuous setup with the demands for Industry 4.0, perfusion biomanufacturing is likely to be a hot topic in the years to come.

Tornadoes occur at a high frequency in the United States compared with other natural hazards but have a substantially small footprint. A single high-intensity tornado can result in high cas...

There is an ever-increasing demand for small optical systems, applications such as cell phone camera lenses, Infrared night vision sensors, and medical devices continue to grow. For these applications, a new compact ultra-precision diamond turning machine offering the highest precision for making both lenses and mold inserts has been developed. A small footprint ideally suited for limited lab space combined with the ability to add a Fast Tool system, optical metrology and automated loading and unloading makes for a versatile yet highly capable machine for precise freeform manufacturing. Unique hardware and software designs yield the highest accuracy on the market.

With increasing adoption of CT coronary angiography (CTA) there is increasing demand for cost-effective, small footprint, dedicated cardiac scanners. We compared a state-of-the-art, small footprint dedicated cardiac scanner (DCCT) to a standard multidetector scanner (MDCT).The study was a retrospective unblinded single centre study. A total of 800 patients were included, with 400 undergoing a DCCT and MDCT coronary CTA scanning, respectively. Image quality was assessed using a 4-point grading score. Image noise and artifact, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and acceptance rate for CT-derived fractional flow reserve (FFRct) were recorded.Overall image quality was higher in the DCCT group (3.8 ± 0.55 vs 3.6 ± 0.69; p = 0.042). There was no difference in overall image noise (p = 0.131) or artifact (p = 0.295). SNR was superior in the DCCT group (14.2 ± 6.85 vs 11.4 ± 3.32; p 0.005) as was CNR (12.7 ± 6.77 vs 11.9 ± 3.29; p 0.005). The heart rate was lower in the DCCT group (56 ± 9.1 vs 59 ± 8.1; p 0.005). No difference in the dose length product (DLP median 244.53 (IQR 105.6) vs 237.63 (IQR 160.1); p = 0.313) or FFRA DCCT scanner is capable of image quality similar to modern current generation general purpose CT technology. Such technology appears to be a viable option to serve the increasing demand for CTCA imaging.

A high voltage PNP device is designed with a small footprint by applying the RESURF technique. It has low turn-on resistance and high failure current. Adjusting the length of LOCOS, the PNP device shows flexibility for different voltage applications from 40V to 90V without failure current degradation.

A new line of G4S detectors has been developed at Crytur, which combines the high-Z scintillators GAGG:Ce and LuAG:Ce with Silicon photomultipliers (SiPM). The detectors’ performance was established by identifying natural radionuclides in samples of rock and building materials. Due to the high detection efficiency of the chosen scintillator materials, and the small footprint of SiPMs, these detectors are very compact and can be made rugged for applications of gamma-ray detection and spectroscopy in the range of 30 keV to several MeV. Crytur’s material development and coupling design make these detectors a superior and affordable alternative to the conventional NaI:Tl based detectors. Due to the compact size these detectors are portable and suited for both lab and field use

Keyword Spotting (KWS) remains challenging to achieve the trade-off between small footprint and high accuracy. Recently proposed metric learning approaches improved the generalizability of models for the KWS task, and 1D-CNN based KWS models have achieved the state-of-the-arts (SOTA) in terms of model size. However, for metric learning, due to data limitations, the speech anchor is highly susceptible to the acoustic environment and speakers. Also, we note that the 1D-CNN models have limited capability to capture long-term temporal acoustic features. To address the above problems, we propose to utilize text anchors to improve the stability of anchors. Furthermore, a new type of model (LG-Net) is exquisitely designed to promote long-short term acoustic feature modeling based on 1D-CNN and self-attention. Experiments are conducted on Google Speech Commands Dataset version 1 (GSCDv1) and 2 (GSCDv2). The results demonstrate that the proposed text anchor based metric learning method shows consistent improvements over speech anchor on representative CNN-based models. Moreover, our LG-Net model achieves SOTA accuracy of 97.67% and 96.79% on two datasets, respectively. It is encouraged to see that our lighter LG-Net with only 74k parameters obtains 96.82% KWS accuracy on the GSCDv1 and 95.77% KWS accuracy on the GSCDv2., Accepted for Interspeech2021

Knowledge of the isocitrate dehydrogenase (IDH) mutation status of glioma patients could provide insights for decision-making during brain surgery. However, pathology is not able to provide such information intraoperatively. Here we describe the first application of a miniature mass spectrometer (MS) to the determination of IDH mutation status in gliomas intraoperatively. The instrumentation was modified to be compatible with use in the operating room. Tandem MS was performed on the oncometabolite, 2-hydroxyglutarate, and a reference metabolite, glutamate, which is not involved in the IDH mutation. Ratios of fragment ion intensities were measured to calculate an IDH mutation score, which was used to differentiate IDH mutant and wild-type tissues. The results of analyzing 25 biopsies from 13 patients indicate that reliable determination of IDH mutation status was achieved (p = 0.0001, using the Kruskal-Wallis non-parametric test). With its small footprint and low power consumption and noise level, this application of miniature mass spectrometers represents a simple and cost-effective platform for an important intraoperative measurement. Graphical abstract.

Micro/nanoscale multicolor barcodes with unique identifiability and a small footprint play significant roles in applications such as multiplexed labeling and tracking systems. Now, a strategy is reported to design multicolor photonic barcodes based on 1D Ln-MOF multiblock heterostructures, where the domain-controlled emissive colors and different block lengths constitute the fingerprint of a corresponding heterostructure. The excellent heteroepitaxial growth characteristics of MOFs enable the effective modulation of the coding structures, thereby remarkably increasing the encoding capacity. The as-prepared multicolor barcodes enable an efficient authentication and exhibit great potential in fulfilling the functions of anti-counterfeiting, information security, and so on. The results will pave an avenue to novel hybrid MOFs for optical data recording and security labels.

Radiosynthesis of [1-11C]acetate is well described in literature, but all syntheses either require adaptations in complex commercial synthesizers or rely on closed-source hardware and software control. Arduino microcontrollers are ideal for the compact, flexible, and inexpensive control of low-complexity hardware, making them particularly suited for radiochemistry where operation in space-limited shielded hot cells is mandatory. We established a [1-11C]acetate radiosynthesis module for combination with a [11C]MeI module available in almost every lab working with 11C. Its small footprint even enables back-to-back production in a hot cell already occupied by other modules. Using this setup, we achieved a reliable and flexible supply of this tracer, with radiochemical yields of 51.4 ± 28.2% and radiochemical purities (RCPs) of 94.4 ± 6.7% ( n = 9) in a synthesis time of 15 minutes. Positron emission tomography (PET) and biodistribution analysis demonstrated low background uptake in healthy mice, with highest uptake in liver and kidneys. Arduino microcontrollers have become valuable and versatile tools in our lab for the automatization of low-complexity procedures not requiring full-blown commercial radiochemistry synthesizers, as showcased here for the production of [1-11C]acetate.

We present a sensor system to monitor the uptake of oxygen by mammalian cells as a direct indicator for the metabolism under consideration of the requirements for the usage in biolabs. That includes reliable oxygen sensing as well as a small footprint of the setup without sophisticated external equipment, the usage of compatible materials and the suitability for a high degree of integration and automation. These requirements are fulfilled by a system that consists of a microfluidic chip with an integrated oxygen-sensitive phosphorescent film, heater and temperature sensor, external optical read-out and 3D-printed holders and housing. The chip with the closed microfluidic chamber is made by clean-room technologies out of silicon and glass. An excitation LED and a small and low-cost Raspberry Pi camera are used to measure the phosphorescent signal. With this system, the concentration of dissolved oxygen can be determined with an accuracy of ±0.8% (air) for oxygen concentrations between 0 and 26% (air) and at any temperature between 23 and 41 °C. To demonstrate the capabilities, the oxygen consumption rates of HaCaT-cells (human keratinocyte cell line) are determined at different temperatures.

The need for continuous size downscaling of silicon transistors is driving the industrial development of strategies to enable further footprint reduction1,2. The atomic thickness of two-dimensional materials allows the potential realization of high-area-efficiency transistor architectures. However, until now, the design of devices composed of two-dimensional materials has mimicked the basic architecture of silicon circuits3-6. Here, we report a transistor based on a two-dimensional material that can realize photoswitching logic (OR, AND) computing in a single cell. Unlike the conventional transistor working mechanism, the two-dimensional material logic transistor has two surface channels. Furthermore, the material thickness can change the logic behaviour-the architecture can be flexibly expanded to achieve in situ memory such as logic computing and data storage convergence in the same device. These devices are potentially promising candidates for the construction of new chips that can perform computing and storage with high area-efficiency and unique functions.

A scalable asymmetric Y-junctions waveguide mode (de)multiplexer ((de)MUX) is theoretically proposed. The high-order mode in the stem is designed to be separated from the lower-order mode and evolves into the fundamental mode in the narrow arm, through waveguide widths optimization by effective index matching and beam propagation method. Within the wavelength range from 1450 to 1630 nm, the four modes (de)MUX with small footprint of 23 × 3. 2 μ m 2 demonstrates the insertion loss and crosstalk of less than 0.14 dB and -16 dB, respectively. This scheme may be expanded to handle more modes in (de)MUX design.

To provide a satisfactory lift service to super high-rise buildings (while maintaining a small footprint for the lift hoistways), ropeless multi-car per hoistway system may be the trend. In our previous paper, a simplified machine model and two primitive controllers were adopted and various features of such a ropeless lift car driven by a linear permanent magnet synchronous motor were illustrated by simulation. In this paper, imperfections including pole saliency, various types of friction such as Coulomb, viscous and Stribeck friction, cogging force and end-effect, etc. were considered. The controllers, control interval and simulation interval were improved in both quantity and quality to arrive at a controllably stable operation. For safety during a genuine power failure, the free-falling terminal speed was estimated both by analytical calculation and computer simulation with consideration of such imperfections. It was confirmed that a desirable operation could be achieved by having smaller and practical winding resistance and inductances, larger and practical permanent magnet magnetic flux, and an optimal pole pitch. This paper could be considered an enhanced version of the pervious paper in that the illustration is more realistic when imperfections are considered. It is hoped that experimenters would further verify the findings in this paper so that such technology could become popularly employed in the future lift industry. Practical application: Multi-dimensional multi-car in a hoistway configuration involving linear permanent magnet synchronous machines would become popular in the near future. This paper introduces a more comprehensive mathematical framework by taking into account of the imperfections in the design and evaluation of controllers as well as the drive performance for a multi-car lift system. The results may give lift designers and researchers a hint on how to design the machines and the controllers with the consideration of imperfections in terms of winding design with variation in resistance, inductance, magnetic field strength, pole pitch, saliency and different types of friction. The paper is aimed at providing lift designers and researchers with a more realistic picture to welcome the new age of multi-car multi-dimensional lift technology.

In recent years, significant advances in NMR system miniaturisation (e.g., electronic console, radio-frequency probe, microfluidic-based chip) utilising small footprint permanent magnets (

Three-dimensional large scale integration (3D-LSI) packaging is crucial toward obtaining increased circuit density within a small footprint. In a 3D-LSI package, chip-to-chip interconnection is typically obtained using through-silicon vias and microbumps. In particular, microbumps realized by nanoparticle deposition (NPD) are promising to obtain high-density interconnections. However, the effect of temperature on the mechanical properties (i.e., hardness) of NPD bumps is little understood. This paper seeks to investigate the influence of temperature on the hardness of NPD bumps, with reference to NPD films. The results obtained suggest a significant reduction in the NPD bump hardness from room temperature to 200 °C. In particular, the hardness was observed to be mainly dependent on temperature rather than grain size, as the grain microstructures obtained at room temperature and 200 °C are similar. Overall, these results suggest a simple approach to control the NPD bump compression during flip-chip bonding, where the hardness-temperature data for the NPD bumps suffices to estimate for the bump compression during flip-chip bonding.