Training for the Third Wave of Mission:

https://place.asburyseminary.edu/firstfruitspapers/1064/thumbnail.jp

Dry film photoresist-based microfabrication: a new method to fabricate millimeter-wave waveguide components

This paper presents a novel fabrication method based on dry film photoresists to realize waveguides and waveguide-based passive components operating at the millimeter-wave frequency (30–300 GHz). We demonstrate that the proposed fabrication method has a high potential as an alternative to other microfabrication technologies, such as silicon-based and SU8-based micromachining for realizing millimeter-wave waveguide components. Along with the nearly identical transfer of geometrical structures, the dry film photoresist offers other advantages such as fewer processing steps, lower production cost, and shorter prototyping time over the conventional micromachining technologies. To demonstrate the feasibility of the fabrication process, we use SUEX dry film to fabricate a ridge gap waveguide resonator. The resonator is designed to exhibit two resonances at 234.6 and 284 GHz. The measured attenuation at 234 GHz is 0.032 dB/mm and at 283 GHz is 0.033 dB/mm for the fabricated prototype. A comparative study among different existing technologies indicates that the reported method can give a better unloaded Q-value than other conventional processes. The measured unloaded Q-values are in good agreement with the simulated unloaded Q-values. The signal attenuation indicates that SUEX dry film photoresists can be used to fabricate passive devices operating at millimeter-wave frequencies. Moreover, this new fabrication method can offer fast and low-cost prototyping

Using Building Commissioning to Improve Performance in State Buildings

Using the commissioning process, states are beginning to improve and optimize their existing building stock as well as ensure that their new construction projects perform according to design. This paper reports on the progress a number of states are making in the area of commissioning for both new construction and existing buildings. It discusses the various programmatic approaches they are using to incorporate commissioning into state energy management programs and new construction projects. It also reports the results of a recent survey of members of the National Association of State Facility Administrators (NASFA) on their use and understanding of commissioning for new construction and existing buildings. The results of two commissioning case studies, one for a new construction project in the State of Montana and one for an existing building in the State of Tennessee are reviewed. Key Words: Commissioning, Survey

Retrocommissioning's Greatest Hits

It is possible to save thousands of dollars in energy costs through a few low-cost operational adjustments but those opportunities are often hidden. Retrocommissioning is a systematic investigation process for improving and optimizing the operation and maintenance of buildings. Although owners' priorities for RCX projects may vary, it typically focuses on energy-using equipment such as lighting, HVAC, refrigeration, and the related controls. This paper highlights key findings from several of PECI's retrocommissioning projects that have produced significant benefits for low costs. The RCX measures are described along with the estimated savings, simple paybacks, and related benefits

A silicon straight tube fluid density sensor

In this paper, a new and simple silicon straight tube is tested as a fluid density sensor. The tube structure has a hexagonal cross section. The fabrication process consists of anisotropic silicon etching and silicon fusion bonding. A tube structure with a length of 2.65 cm was tested. The sample volume is 9.3 μL. The first three modes of vibrations were investigated with a laser Doppler vibrometer for air and five liquid mixtures. The fluid density sensitivity of each mode was measured and the average was −256 ± 6 ppm (kg m−3)−1 around the density of water. The density of an unknown fluid can be continuously monitored using this sensor by measuring the resonance frequency of one of the vibration modes and extracting the density from the calibration curves

Silicon straight tube fluid density sensor

In this paper, a micromachined silicon straight tube is tested as a fluid density sensor. In comparison with other density measurement techniques, the use of micromachined tubes require small sample volumes and allows continuous monitoring of the fluid density in microfluidic systems. Different vibration modes of the sensor were detected and calibrated using a laser Doppler vibrometer (LDV). Linearity, simplicity, the straightforward fabrication and evaluation, the low flow restriction and reduced risk of trapping gas in the sensor due the absence of corners are the design's main advantages. The ability of the sensor to measure density of multiphase fluids and provide accurate results independent of other fluid parameters, allows it to be used in varying fields such as the biomedical, pharmaceutical and petrochemical industries

Micromachined contactless pin-flange adapter for robust high-frequency measurements

We present the first micromachined double-sided contactless WR03 pin-flange adapter for 220-325 GHz based on gap waveguide technology. The pin-flange adapter is used to avoid leakage at the interface of two waveguides even when a gap between them is present and can be fitted onto any standard WR03 waveguide flange. Tolerance measurements were performed with gaps ranging from 30-100 mu m. The performance of the micromachined pin flange has been compared to a milled pin flange, a choke flange and to standard waveguide connections. The micromachined pin flange is shown to have better performance than the standard connection and similar performance to the milled pin flange and choke flange. The benefits of micromachining over milling are the possibility to mass produce pin flanges and the better accuracy in the 2D design. Measurements were performed with and without screws fixing the flanges. The flanges have also been applied to measure two devices, a straight rectangular waveguide of 1.01 inch and a ridge gap resonator. In all cases, the micromachined pin flange performed flawlessly while the standard flange experienced significant losses at already small gaps

Об изучении иностранными студентами-медиками лексической синонимии в процессе усвоения языка специальности

This paper considers design issues for microvalves for large gas flow control. It introduces out-of-plane knife-gate microvalves as a novel design concept and a proportional microvalve concept for pressure control applications. The design of three different actuator-gate configurations and first prototypes are presented. The first valve prototypes feature thermal silicon-aluminum bimorph actuators and the pressure-flow performance per chip area of the demonstrator valve presented is greatly increased using out-of-plane actuation and an out-of-plane orifice. The characterization of the actuators and of the pressure-flow performance is presented. The prototype valve allows for a flow change of Delta Q = 3.4 standard liters per minute (SLPM) at a pressure change of Delta P = 95 kPa (P-in = 196.3 kPa, P-out = 101.3 kPa) on an active chip area of only 2.3 x 3.7 mm(2).QC20100727</p

Silicon straight tube fluid density sensor

In this paper, a micromachined silicon straight tube is tested as a fluid density sensor. In comparison with other density measurement techniques, the use of micromachined tubes require small sample volumes and allows continuous monitoring of the fluid density in microfluidic systems. Different vibration modes of the sensor were detected and calibrated using a laser Doppler vibrometer (LDV). Linearity, simplicity, the straightforward fabrication and evaluation, the low flow restriction and reduced risk of trapping gas in the sensor due the absence of corners are the design's main advantages. The ability of the sensor to measure density of multiphase fluids and provide accurate results independent of other fluid parameters, allows it to be used in varying fields such as the biomedical, pharmaceutical and petrochemical industries