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The purpose of this study is to use infrared spectroscopy (FTIR) for monitoring biological changes in burned skin. Wistar rats dorsum samples were compared to healthy group samples at 7, 14, 21 days after burn. Proteins changes of burn wounds were monitored by area under the curve (AUC) of bands at 1630 cm1, 1543 cm1 and 1743 cm1. Kruskal-Wallis normality tests, unpaired t test with Welch's correction were used to evaluate the differences between AUC. These bands suggest association between collagen activity during wound healing stages. Our result indicates progressive recovery of 7,14 and 21 days tissues when compared with the healthy group.

Interference signals are a severe threat to any GNSS receiver. Due to the low reception power of satellite signals, even comparably weak interferences can significantly decrease the positioning accuracy of the receiver or lead to a complete signal loss. Therefore, any active interference signal has to be mitigated to ensure a continuous and safe operation. This is especially important in the field of automated driving, where the permanent awareness of a human being is no longer presumed and cars rely solely on GNSS to determine the absolute position necessary for navigation. While uniform rectangular arrays have shown to be the most effective method against interference signals by providing the ability to spatially mitigate incident signals, their size prevents an application in cars produced for the consumer mass market. This paper presents an arrangement, where a set of two distributed linear arrays is used, which seems promising for a concealed installation and allows the application of spatial signal processing algorithms such as beamforming and nulling. Consequences on the positioning accuracy from the joint processing of signals from distributed antenna elements are discussed and the capability to mitigate interference sources is demonstrated.

Novemdecuple (19-element) electrically parallel, optically uncoupled vertical cavity surface emitting laser arrays exhibit 18 GHz bandwidth, transmit pseudorandom digital data at 25 Gb/s with a bit error ratio of 1 x 10-13, and emit up to 200 mW at 980 nm.

A novel proposal is made for the accurate determination of position and antenna attitude of a multi-antenna GNSS receiver in a multipath environment. In contrast to previous work no calibration of the gain and phase mismatches and crosstalk effects, that occur in the RF-Frontend, are necessary. This allows for the usage of heavily miniaturized RF-Frontends with highly integrated systems with non-negligible crosstalks and tolerances. The novel algorithm treats the estimation of antenna attitude, the multipath detection and mitigation as well as the calibration as a coupled problem and estimates the relevant unknowns in a joint procedure. Due to this approach a reliable position estimate can be determined even in challenging conditions without the need for very accurately calibrated - or nearly “ideal” hardware components.

Recent research has provided new, domain-specific number systems that accelerate modern workloads. Using these number systems effectively requires analyzing subtle multiprecision, multi-format (MPMF) code. Ideally, recent programming tools that automate numerical analysis tasks could help make MPMF programs both accurate and fast. However, three key challenges must be addressed: existing automated tools are difficult to compose due to subtle incompatibilities; there is no “gold standard” for correct MPMF execution; and no methodology exists for generalizing existing, IEEE-754-specialized tools to support MPMF. In this paper we report on recent work towards mitigating these related challenges. First, we extend the FPBench standard to support multi-precision, multi-format (MPMF) applications. Second, we present Titanic, a tool which provides reference results for arbitrary MPMF computations. Third, we describe our experience adapting an existing numerical tool to support MPMF programs.

Transitions for planar transmission lines on printed circuit boards to rectangular waveguide are challenging to design and manufacture. This paper introduces two transitions, the first one is a broadband transition from WR12 (60–90 GHz) waveguide to a stripline (SL) and the second is a narrowband transition to a grounded coplanar waveguide (GCPW). The focus at the first transition is based on the fact that signals can be transmitted in the complete E-Band. In the process, many manufacturing possibilities were exploited. For the second transition, the focus was on manufacturability in order to achieve the most cost effective transition possible. Design, simulated and measured results will be presented.

Compact groups of three electrically-parallel 980 nm oxide-confined vertical-single-cavity surface-emitting lasers via on-wafer probing exhibit record room temperature small-signal modulation bandwidths of 20 to 25 GHz and corresponding large optical output powers of 60 to 20 mW, respectively, and back-to-back 25 Gbps error-free data transmission.

This paper presents a new method to produce different kinds of RF waveguides with reduced attenuation on low cost PCB substrates. First, microstrip (MS) and grounded coplanar waveguides (GCPW) are characterized by considering rough conductors in CST Microwave Studio. Next, laminate is partially removed, to increase the electromagnetic field ratio in air. Accordingly, the dielectric losses are reduced and the electrical length is decreased. These conductors are produced by using a CO2 laserdrilling machine to remove the undesired substrate. The RF performance (DC to 100 GHz) of these waveguides is compared to transmission lines manufactured in conventional PCB technology. Finally, different kinds of simulated and produced microstrip filters are shown and fabrication tolerances are compared to those produced in standard technology.

Efficient biochemical characterization of skin burn healing stages can improve clinical routine to adjust patients treatment. The golden standard for diagnosing skin burning stages is the histological biopsy. This practice is often expensive and technically challenging. There have been advances in the treatment, and diagnostic of the critical skin burned patients due to the increase of multidisciplinary collaboration. The contributions from different fields of biomedical engineering motivate to develop a better procedure for clinical applications. Considering the difficulty of monitoring wound healing the Fourier Transform Infrared coupled with an Attenuated Total Reflectance (ATR-FTIR) accessory is an analytical technique that can provide information regarding spectral biomarkers in biological materials. This study aimed to evaluate the classification feasibility provided by ATR-FTIR technique in the burned skin to follow the regenerative process in vivo. 40 skin burned samples from the Wistar rats dorsum at 3,7, 14, 21 days after burn were compared with the corresponded healthy group samples, by registering their infrared absorption spectra in FTIR Thermo Nicolet 6700 coupled to a diamond crystal ATR. The spectra were separated in the region 900 to 1800 cm−1 for further chemometric calculations. The second derivative of spectra was applied for discrimination, which results demonstrated differences from control and burns wounded groups, as well as among, burn wounded groups, using Amide I (1628 cm−1) and Amide II (1514 cm−1) bands. Amide I and Amide II bands are two significant bands of the infrared protein spectrum. The Amide I band is mainly associated with the C=O stretching vibration (70-80%) and is directly related to the backbone conformation. The Amide II band results from the N-H bending vibration (40-60%) and from the C-N stretching vibration (18-40%). This band is conformationally sensitive. These bands suggest proteins activity changing associate to inflammatory and maturation stages when it is compared with the healthy group. The statistical difference with amide I occur in proliferation and maturation stages. These findings indicate that ATR-FTIR is suitable to detect the burn wound healing stages and in the future can be an auxiliary instrument for clinical routine. This study was supported by CEPID/FAPESP 05/51689-2, CAPES/PROCAD 88881.

Vertical-single-cavity surface-emitting lasers emitting in a quasi-single mode at 980 nm and based on a simplified epitaxial design with oxide aperture diameters of about 3 μm and an output coupling mirror power reflectance below 0.99 exhibit record room temperature small-signal modulation bandwidths of 35 GHz.

This paper presents a comparison of chip connections using aerosol jet (AJ) and bond technology on low-cost printed circuit board (PCB) substrates. First, the behavior of the used gap filler material and the used silver ink for AJ technology on PCBs are characterized. In addition to comparing the radio frequency (RF) performance (DC to 67 GHz) of the two technologies, the mechanical stability is also compared. While the AJ technology transitions score above all for their RF performance and the lower requirements (surface finish, pad size, and adhesion) on the PCB, the bonding technology has clear advantages, especially with a different coefficient of thermal expansion values of the substrates to be connected. Finally, the measurement results of a complete package are shown, whereby the chip connection is realized once by means of AJ and once by bonding wires.

This paper describes a novel approach and its realization for measuring the force distribution within a forming process. Using a modular system integrated between the ram of the machine and the upper die of the forming tool a tool independent application is possible. First metrological examinations will prove the functionality of the system with respect to the detection of process parameter changes and quality indicators. The benefit of such an approach will be shown by means of several use-cases.